B GIO DC V O TO TRNG I HC NNG LM TP.HCMB MN CNG NGH SINH HC

***000***

TH THANH HNG KHO NGHIM MT S PHNG PHP TNG SINH KHI GING TO SPIRULINA PLATENSIS

Lun vn k s Chuyn ngnh: Cng ngh sinh hc

Thnh ph H Ch Minh Thng 9/2006

B GIO DC V O TO TRNG I HC NNG LM TP.HCMB MN CNG NGH SINH HC

***000***

KHO NGHIM MT S PHNG PHP TNG SINH KHI GING TO SPIRULINA PLATENSIS

Lun vn k s Chuyn ngnh: Cng ngh sinh hc

Gio vin hng dn: PGS. TS. TRN TH DN KS. NGUYN VN T

Sinh vin thc hin: Tn: BI TH NGC BCH Kha: 2002 2006

Thnh ph H Ch Minh Thng 9/2006

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MINISTRY OF EDUCATION AND TRAINING NONG LAM UNIVERSITY, HCMCDEPARTMENT OF BIOTECHNOLOGY

***000***

TRYING SOME METHODS FOR INCREASING WEIGHT OF SPIRULINA PLATENSIS IN THE LABORATORY

Graduation thesis Major: Biotechnology

Professor: Ms.LE THI PHUONG HONG

Student: DO THI THANH HUONG Term: 2002 2006

HCMC 9/2006

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PHN I : M U1.1 t vn Ngy nay, vi s bng n ca cuc cch mng khoa hc k thut, vic tm ra ngun nguyn liu va r tin m cht lng khng cn l tr ngi ln na. Cng nh vy, thc phm dnh cho ngi dn c thay th bi thc phm chc nng. C th ni trong nhng nm gn y, vic nghin cu tm v khai thc cc loi nguyn liu nng cao gi tr dinh dng b sung vo thc phm ngy cng c quan tm nhiu hn. Spirulina platensis cng l mt trong nhng mi quan tm . Ngi ta nghin cu v Spirulina platensis rt nhiu, khng nhng v chng c gi tr dinh dng cao m cn bi chng c nhiu tc dng trong c y ln sinh hc. Theo Prescott, Gorrunov v cng s (1969) cho rng, trong tng lai y dc v nhng s tm kim trong y dc, bao gm c vic nghin cu v th nghim cc to c th k ra nh vic tm kim thuc cha ung th, d ng, to tit cht khng sinh c th thay th cho Penixilin. Trong tng lai s c mn cha bnh dng to (Algotherapia hay Phycotherapia) (trch dn bi Nguyn Vn Tuyn, 2003). Vic tng sinh khi to m vn gi c cht lng tt qui m phng th nghim s l hng m p dng cho qui m sn xut cng nghip, ng thi c th xc nh c nh hng ca cc thnh phn dinh dng cho s pht trin tt hn ca to. Xut pht t nhng yu cu , chng ti thc hin ti : Kho st mt s phng php tng sinh khi ging to Spirulina platensis qui m phng th nghim. 1.2 Mc ch nghin cu S dng mt s phng php khc nhau nhm tng sinh khi to m vn gi c cht lng tt. T , tm ra phng php tt nht c th ng dng qui m sn xut cng nghip. Thay i t l cc thnh phn trong mi trng nui cy, kho st nh hng ca nng cc thnh phn ti s tng sinh to. La chn phng php thch hp nht cho kh nng thu hoch to cao.

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M t nguyn tc cu to v nguyn l hot ng ca my khuy t vic thit k my khuy to dung tch nh. 1.3 Yu cu Kho st nh hng ca mt s thnh phn mi trng nui cy. Kho st c nh hng ca iu kin nui cy ti vic tng sinh to. Kho st phng php thu hoch to. Kho st nh hng ca t l nui cy ban u ti vic thu hoch to. xut a ra m hnh my khuy to dung tch nh.

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PHN II : TNG QUAN TI LIU2.1 To Spirulina platensis 2.1.1 Lch s pht trin v cc cng trnh gy nui to Spirulina trong v ngi nc Con ngi t xa dng rong to lm thc phm, nh ngi Trung hoa bit n to bin t 600 nm trc cng nguyn. Tng t ngi dn cc qun o thuc Nam Thi Bnh Dng v Nht Bn dng nhiu ging to lm thc phm, nh Porphyra, Ulva, Alaria v.v...C l l nhng dn tc s dng rong to sm nht trn th gii ny, h thu hi rong to t nhin v dng lm rau n hay ngun thc phm b dng. Vi to Spirulina c coi nh ca tri ph cho 2 sc dn, Aztec Mexico (Chu M) v Kanembu, mt b tc thuc Tchad (Chu Phi). T thi c xa, 2 b tc trn bit thu ging rong sng t nhin ny sng trong cc h nc khong giu kim ch bin thc n rt b dng nh : bnh bao, nc chm, nu canh soup. Trong gii khoa hc, c l to ny c m t v t tn l Spirulina do hnh dng xon l so ln u tin nm 1827. Vic pht hin v pht trin to ra khp th gii gn lin vi lch s tm ra Tn Th Gii Chu M ca Christophe Colomb, nm 1492. Tip theo s kin ny, cc bi vit v cc loi thc n t Spirulina ca ngi Aztec, nh mn bnh Techuilatl c truyn b Chu u. (L nh Lng, 1999). Nm 1931, Rich tham quan cc h trong thung lng Rift vng ng Chu Phi nhn xt thy mi trng sinh thi ca hng hc vi thc n t nhin l to. Nm 1940, Dangeard nhn ra rng cc bnh to xanh dng lm nc chm hng ngy ca dn cc h cnh vng Chad vi thc n ca hng hc thung lng Rift l mt, chnh l to Spirulina. Nm 1960, ng Duran Chastel gp kh khn trong vic sn xut Soude ca cng ty Sosa Texcoco, ngu nhin pht hin ra mt loi vi sinh vt lm chm c ch kt tinh ca mui carbonate trong cc b bc hi, chnh l to Spirulina. (Nguyn Thanh Bch Ngc, Nguyn Hng Hnh, 1997).

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Tuy vy, mi n nm 1960 khi Leonard & Comper ngi B phn tch cng b gi tr dinh dng ca bnh Dihe, thc n ca ngi Kanembu lm t Spirulina cha hm lng protein rt cao, th gii khoa hc mi quan tm nhiu hn. Nm 1963, gio s Clement thuc Vin nghin cu du ha quc gia Php l ngi u tin nghin cu thnh cng vic nui to Spirulina qui m cng nghip. Theo nghin cu ny, ging to Spirulina t Tchad c s dng trong nui cy vi nh dng CO2 rt di do ti cc m khai thc du ho. Vy ngi Php i tin phong trong vic nui nhn to Spirulina v thng mi ho sn phm ny. c bit nm 1967, nhng ngi tin phong li c dp trin khai nhng nghin cu ca mnh, do bo co ca Clement c trnh by ti Hi ngh quc t v du ha ti Mexico c cng ty Sosa Texcoco thch th. Lin doanh sn xut cng nghip to Spirulina s dng ngun nc khong bicarbonat gia Vin nghin cu du ha Php v cng ty Sosa Texcoco c thnh lp. T n nay, lin doanh ny lun dn u th gii v lng to Spirulina quy m cng nghip. K ngh nui trng Spirulina v mt s vi to khc (Chlorella, Klamath,...) hoc nm si tr thnh mt lnh vc c u t pht trin trong cng ngh sinh hc to sinh khi protein. Thc ra, Spirulina khng phi l th to c nghin cu u tin, m l to Chlorella. Nh ti Hoa K, nhng nm 1948 1952 nhiu nghin cu nui to Chlorella c trin khai. n nm 1970, gi tr ca to Spirulina c cng nhn, vi u th nhiu mt, th s pht trin nui trng quy m cng nghip ging to ny n r nhiu quc gia. Ti Nht Bn, c s h tr k thut t Hoa K tin s Nakamura tin hnh nhng nghin cu sm nht vo nm 1968, vi ging to m t Tchad. Phng php nui trng cng nghip Spirulina ca ng c trin khai vi vng ca Nht Bn, Thi Lan v Hn Quc. Vi u t ca nhiu cng ty kinh doanh, cc d n ny pht trin thnh nhng x nghip chuyn sn xut to Spirulina. Ti n , nghin cu nui cc ging to cng c trin khai t nhng nm 1960, c bit m hnh nui Spirulina quy m cng ng nh (lng, x), do Ripley D. Fox khi xng pht trin kh tt mt s vng nh Karla Schechardy. R.D. fox, ngi

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Php dy cng nghin cu sut 15 nm (1968 1983), v xy dng c mt phng th nghim nghin cu Spirulina Php. ng thi sng to c m hnh nui to Spirulina, cung cp ti ch cho vic phng chng dinh dng tr em. M hnh ny c nhiu nc ngho, ang pht trin nghin cu p dng nh Peru, Tog... v Vit Nam. Ngoi cc nc nu trn, to Spirulina cn c pht trin nhiu quc gia v vng lnh th Trung Quc, Singapore, i Loan, Bulgarie, Ukraina, H Lan, Italia, Ty Ban Nha, Czech, Nam Phi, Chi L, Isarel, Maroc, Iran, Cuba, Hng Kng, v.v... nc ta, to Spirulina c di thc nhp ging lu gi ti Vin Pateur Paris Cng Ho Php, v nghin cu t nm 1972 Vin Sinh Vt (Vin Khoa Hc Vit Nam). Nghin cu quy trnh k thut nui trng do Vin ny ch tr, cng vi s tham gia nghin cu v ho hc v gi tr dinh dng tr bnh ca Vin y hc qun s, v tc dng lm sng ca Vin qun y 108 H Ni. ti ny mc phng th nghim, cho mt kt qu tin lng tt v kh nng nui trng ny nc ta theo m hnh ngoi tri, khng mi che, c sc kh carbonic (CO2), ng thi khng nh gi tr dinh dng v cha bnh ca Spirulina, m hng tin phong cho cc nghin cu v Spirulina. Ti nm 1977, Vin sinh vt ni tin phong ca k ngh to Spirulina Vit Nam, li trin khai kt qu trn mc ln hn, khi ti ny c s u t ca nh nc v cc b c lin quan, v c bit ni n nhn l x nghip nc sui Vnh Ho (Bnh Thun). Ti y s dng ngun nc sui khong giu bicarbonat, natricarbonat thin nhin, mt li th ca a phng. Ngoi ra, cn s dng nng lng sc gi vn hnh h thng my khuy trn mi trng nui to. Tham gia nghin cu c trng i hc Bch Khoa H Ni (ch to cc thit b nui to), Vin y hc qun s, x ngip dc phm TW 24 Mekophar (bo ch cc dc phm), bnh vin Thng Nht TP.HCM, bnh vin ph sn T D TP.HCM (nghin cu lm sng cc dng thuc...). Ngoi ra mt s nghin cu khc v ng dng ca Spirulina trong chn nui gia cm v thu sn, tm t cng c trin khai ti trng i hc tng hp H Ni, y ban khoa hc k thut nh nc v S nng nghip H Ni, H Bc, Thi Bnh, Lm ng, TP.HCM...

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Nhm tc gi trn do c gio s Nguyn Hu Thc (y ban khoa hc k thut nh nc) v cc cng s Trn Vn Ta, Phan Phng Lan, ng nh Kim (Vin sinh vt) cn nghin cu s dng ngun dinh dng khc nui to nh nc thi m t tm ti an Hoi (H Ty), Bo Lc (Lm ng), nc sui khong cmin (Bun Ma Thut). Nh vy vi ti cp nh nc (M s 48.01.02.03) tng kt thng 4 nm 1986, nh du bc tin b a kt qu nghin cu t phng th nghim ra ng dng quy m cng nghip, ha hn nhiu trin vng ca ging to qu ny nc ta. Ti thnh ph H Ch Minh nhiu nghin cu v Spirulina cng c tin hnh ti : + S y t TP.HCM, t nm 1985 tip nhn ging to Spirulina u tin do ng b R.D. Fox tng thnh ph, v giao cho Trm nghin cu dc liu gi ging, nghin cu nui trng. Cc nghin cu sau c hc tp, trin khai theo m hnh s dng Biogas v b sung ho cht. Hin Trung tm dinh dng tr em ang sn xut din tch khong 170 m2 theo phng php ho cht. + Vin sinh hc nhit i TP.HCM (thuc Trung tm Khoa hc t nhin v Cng ngh quc gia), t nm 1989 trin khai nghin cu k thut vi s h tr ca Cng ho Php. Cc nghin cu ny mc phng th nghim, vi cc kho cu nui to theo m hnh biogas t n ..., v nui bng ho cht, nhm tm mt quy trnh thch hp c th ng dng vo thc t. c bit cc nghin cu cn tm quy trnh chit xut mt s hot cht sinh hc t Spirulina ng dng trong sinh ho, y dc... C l trong tng lai ti ny s c ng dng trong mt d n ln v cng ngh sinh hc ca Vin. + C s nui trng v pht trin sn phm to Spirulina (tn giao dch Labo. HELVINAM), ti huyn Bnh Chnh TP.HCM, c thnh lp nm 1994. Di s khuyn khch ca S y t Tp.HCM, y ban nhn dn huyn Bnh Chnh v s nhit tnh ca nhm cn b nghin cu v mt s nh ho tm, c s ny bc u thnh cng. Quy trnh lin hon nui trng v sn xut, s dng mt s ch phm to Spirulina trong dinh dng v lm thuc phng, cha bnh c thit lp. Quy m trong tng lai c

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th l mt trong nhng x nghip chuyn sn xut to ln Vit Nam, vi h nui to kiu nh knh trn 2000 m2 hin c v kh nng m rng. Ngoi ra, cn nhiu nhm nghin cu nhng vn khc nhau ca Spirulina cc trng i hc, cc trung tm nghin cu, cc h gia nh,...trong nc. 2.2.1 Phn loi Spirulina tn gi ca vi sinh vt ny do nh to hc ngi c Deurben t nm 1927, trn c s hnh thi c trng nht l dng si xon (spiralis). Sau ny cc chuyn gia phn loi hc thng nht tn khoa hc y : Ngnh : Cyanophyta Lp : Oscillatoriales H : Oscillatoriaceae Chi : Spirulina Loi : Spirulina platensis V c cu to v chc nng khc cc loi thng thng nn Spirulina cn c tn l vi khun lam hay phiu sinh thc vt. 2.2.2 Phn b Trc ht cc vng nc kim (pH 8-11) c th c Spirulina sng t nhin, nht l cc h, sui khong, m p. V a l to ny c tm thy phm vi rt rng : Chu Phi (Tchad, Cngo, Ethiopia, Kenya, Nam Phi, Ai Cp, Tanzania, Zambia), Chu M (Hoa k, Peru, Uruguay, Mexico), Chu (n , Pakistan, Srilanka, Vit Nam), Chu u (Nga, Ukraina, Hungarie,...). Tng vng c th c tng loi, ging Spirulina khc nhau, hoc mt loi nh S.platensis li c tm thy nhiu nc, c khi rt xa nhau ti na vng tri t. S phn b ny c th do chn lc t nhin, khng k do con ngi ch ng di thc nui trng. Cng c th c di thc theo mt s loi chim di tr, m loi hng lc (Phoenicoraiasmiror), thng n Spirulina Chu M l mt s v d. To Spirulina thng bm vo lng v v theo chim phn b ti nhng ni m hng lc c tr theo ma. Nh vy s lng cc ging, loi ca Spirulina c hng chc

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nhiu vng trn th gii, tc l h gen hay tnh a dng sinh hc (biodiversity) ca chng tht phong ph.(L nh Lng, 1999). 2.2.3. Hnh thi v cu to Theo Frmy (1930) c th hin vi c dng xon l xo vi 5-7 vng xon u nhau. Trichom khng phn nhnh, khng c bao, khng chia thnh cc t bo c vch ngn ngang. Trong t bo c nhng ht nh phn b st mng t bo v nhng loi tri ni trn b mt nc thng c khng bo kh. Chiu di ca Trichom ti 151 micron (gn bng 1,5 mm); chiu rng 5,5 - 6,5 micron, u si hi thun li. Cc vng xon u nhau, ng knh 43 micron, khong cch gia cc vng xon 2,6 micron. Chiu di t bo ln hn 2 micron v bng mt na chiu ngang. Ch vch ngn ngang gia cc t bo hi tht li. Sng trong cc thu vc nc ng, hin nay S.platensis l i tng nui trng cng ngh v sinh khi ca chng giu cht dinh dng v protein (trch dn bi Dng Tin c, 1996). To lam pht trin thnh sinh khi ln h Ba mu (H Ni). (Dng Tin c, 1996). 2.2.4. c im dinh dng ca Spirulina platensis To Spirulina l vi sinh vt quang t dng bt buc, khng th sng hon ton trong ti, quang hp nh nh sng mt tri v c kh nng c nh m rt cao. y l mt trong khong 2500 loi cyanophyta c nht, t dng n gin, c kh nng tng hp cc cht cn thit cho c th, k c cc i phn t phc tp. Mi trng dinh dng ca Spirulina gm : Cc dng cht : trong mi trng nc Spirulina cn ngun dinh dng

carbon, nit, cc cht khong a lng v vi lng...Ngoi ra chng cn cm ng vi mt s cht nh l cht c ch hoc cht kch thch sinh trng. Cc iu kin l ho thch hp : pH, p sut thm thu, nh sng, nhit ,

iu kin khuy trn, v.v... C rt nhiu c im dinh dng ca to ny, nhm trin khai cc quy trnh

sn xut sinh khi kinh t nht. l cc kho cu mi trng t nhin ca spirulina sinh sng, n pha ch cc mi trng nhn to, hoc na nhn to bng b sung cc

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cht vo ngun ti nguyn thin nhin : nc bin, nc sui khong, nc khong ngm, ging khoan..., c th tm lc nh sau : + Dinh dng carbon : To Spirulina ng ho carbon ch yu dng v c, tt nht l bicarbonat (HCO-), thng qua qu trnh quang hp. Phn ng quang tng hp hidratcacbon (ng) v mt s cht khc : HCO3- + 2H2O (CH2O) +O2 + H2O + OHCarbon dng kh CO2 cng c th c s dng nhng phi m bo cho mi trng vng pH kim thch hp. Do vy nhiu tc gi ng ngun cacbon nui Spirulina khong 1,2 16,8g NaHCO3/lt. mi trng bicarbonat ny, c th sc hoc khuy trn khng kh thng (cha 0,03% CO2), hoc ngun kh c 1-2% CO2, nhm iu chnh pH, hoc o mi trng gip t bo trn u, tip xc c vi nh sng. To Spirulina t dng thng qua qu trnh quang hp, dng carbon v c nn thng c nui trng kiu quang t dng (Autotrophic culture). Cc nghin cu ca Ogawa T., Terui G. (1972), v Crance J.M (1975) cho thy Spirulina c th s dng glucose, mui acetat nhng phi s dng nh sng hay quang t dng bt buc. Cc ngun carbon hu c ny c nh du (14C ) nghin cu s phn b trong t bo v theo di s pht trin. Cc cng trnh nghin cu ca Chen F, Zhang Y, Guo S. (1996), cho thy c th nui Spirulina trong iu kin quang t dng (Phototrophic culture), vi ngun carbonglucose-acetat. Nng glucose 1,81 2,66g/l v acetat 0,246 0,322g/l, vi nh sng 2 4 Klux. Kiu nui ny cho sinh khi v hm lng phycocyanin cao, nng sut sinh khi t 5g/l. + Dinh dng nit : To Spirulina v nhiu vi sinh vt c nh nit, ng ho nit theo phn ng kh nh enzyme nitrogenase xc tc khi c ATP. Kt qu nit c tng hp thnh protein ca chng. Kh nng c nh m ca Spirulina rt cao, cho hm lng nit 10% trng lng kh, hay thng trn 50% protein. Nhng Spirulina khng c kh nng s dng nit dng kh N2 m s dng di dng nitrat (NO3-), vi ngng 30 70mg N/L, trung bnh 4 12mg N/L (theo mi trng Zarrouk C). Ngoi ra c th dng

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ngun nit khc : nit amoniac (NH3) dng ny thng c trong cc loi nc thi Biogas, nit amon : (NH4)2SO4 (Amonisulphat- AS), (NH4)2HPO4 (DiamoniphotphatDAP) l cc loi phn bn hay dng trong nng nghip, hoc ur (NH2)2CO. Nu s dng cc ngun nit khc nitrat, cn khng ch nng v d gy sc lm gim nng sut sinh khi, thm ch c th gy cht to.Theo kinh nghim nn khng ch nng nit tnh theo NH3 t 30-70 mg/L hoc di 100mg/L. Vy ngun thc n cho Spirulina c th chuyn i theo cch : Ur (NH2CONH2) Amoniac (NH3) Amonium (NH4+) Nitrat (NO3-). 90 + Cc dng cht khong : o Phtpho v c di dng mui natri, kaliphotphat ho tan 180 mg/L. o Kali K+ v Na+ : di dng mui cloride hoc vi dng kt hp vi ngun nit, photpho. To Spirulina rt a mui, trong mi trng u trng nht cha kali ti 5g/L v natri ti 18g/L. Trong thc nghim mt s kin cho rng t l K+/Na+ nn nh hn 5, ln hn to s chm pht trin, hoc hn na gy ri lon t bo, ph v ct trc t bo to. o Magie (Mg+2) : ng vai tr tng t nh photpho, trong tng hp cc ht polyphotphat. o Canxi (Ca+2) : khng gy nh hng r n sinh trng ca to. o St : l nhng dng cht thit yu, nh hng trc tip ti sinh trng v hm lng ca protein. St thng dng dng mui FeSO4 (0,01g/L). C th dng st dng phc EDTA (Etylen diamin Tetracetic acid), phc ny ho tan bn hn trong kim so vi dng v c. Nng Fe2+ trong mi trng rt rng t 0,56 56mg/L mi trng. o Clo (Cl-) to ny rt a clo v c, nng dng vi mui NaCl, khong 1 1,5g/L.

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o Cc khong vi lng khc : Bo (B3+), km (Zn2+), Mangan (Mn2+), ng (Cu2+), Coban (Co2+) ...l cc vi lng c dng, nhng nh hng khng r n sinh khi protein, nhng li c nh hng ti mt s thnh phn khc nh vitamin... Spirulina c th b tc ng bi cc kch thch t (hormon), gip to tng trng nhanh hn nh indol axeticacid (AIA), gibberelic acid (GA3)...Mt s cng trnh nghin cu chng t Spirulina c sn sinh cc hormon tng trng hot tnh kiu auxin, gibberelin v cytokinin. Cc hormon ni sinh ny kch thch nng cao sinh khi cn tng tc sinh sn s si to. (L nh Lng, 1999). 2.2.5. c im sinh sn ca Spirulina platensis Theo Keeton (1967) s phn chia t bo to lam c th hin bi s ct i (binary fission), nh cc vi khun, v cng thng bi s phn on ca cc si (trch dn bi L Th Phng Hng, 1996). To on l mt trong nhng hnh thc sinh sn ph bin ca vi khun lam dng si. To on l nhng on to c hnh thnh t cc trichom, thng c kch thc khc nhau, gm c t 2 - 3 t bo, n s lng nhiu hn, c kh nng chuyn ng tch cc nh trt trn gi th do tit ra cht nhy. (Dng Tin c, 1996). Cc si to trng thnh b ct ra thnh vi on to (hormogonia), mi on to c t 2 - 4 t bo, nh s thnh lp ca vi t bo c bit, gi l hoi bo (necridia). Hoi bo c mu xanh vng, d nhum vi congo, v b thu gii cho cc t bo hnh a tch ri c hai mt lm (Phm Hong H, 1972). S ph v cc si to nh th c tnh ngu nhin, nhng khng bt k (v ch xy ra ni cc hoi bo). (L Th Phng Hng, 1996). Theo Boussiba (1989) cc on to con, sau khi tch ri nhau, trt nh khi si cha m. Hai u xa ca on to, mt i phn dnh ca hoi bo, tr nn trn vi vch mng. S t bo trong cc on to gia tng bi s ct i t bo, hay chnh xc hn s phn chia xen gia (intercalary cell division). Qua qu trnh ny, cc si ko di ti mc trng thnh v c dng xon kiu mu. Trong cc iu kin tng trng ti ho, thi gian tng gp i ca S.platensis l 9,3 gi (trch dn bi L Th Phng Hng, 1996).

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Theo Nguyn Ln Dng (1980) c lng s tng trng ta c th o chiu di, chiu cao, chiu rng, din tch, th tch, trng lng ti hay kh, s lng t bo,...(trch dn bi L Th Phng Hng, 1996). 2.3 iu kin nui cy v cc yu t nh hng n qu trnh nui to Spirulina platensis C th ni ngoi cc iu kin dinh dng c bn th qu trnh nui cy Spirulina cn b chi phi bi cc yu t khc. 2.3.1 nh hng ca nh sng L thc vt bc thp cha dip lc, vi to thc hin qu trnh quang hp theo c ch nh thc vt bc cao. Hot ng u tin ca quang hp l hp thu nh sng. (ng nh Kim, ng Hong Phc Hin, 1998). Theo Seshadri & Thomas (1979), s tc ng ca nh sng ti Spirulina bi hai yu t chnh l thi gian v cng chiu sng. Qu trnh nui cy ngoi tri th cng nh sng ti ho cho Spirulina trong khong 20 30 klux. (trch dn bi L Th Phng Hng, 1996). V thc hnh nui cy Spirulina cn ghi nhn vi thng s c lin quan n ch nh sng nh : cng nh sng ti u = 25000 30000 lux, khong ny hot tnh quang hp cao nht, cn iu chnh t c trong nui cy.(L nh Lng, 1999). Ngoi ra cng nh sng cn ph thuc vo mt nui cy ca to, v khi cng nh sng cao m mt to ln th mi si to vn nhn c cng nh sng nh. Nhiu loi vi to c cng quang hp bo ho khong 33% tng lng cng nh sng. V vy trong iu kin nh sng c cng cao v thi gian chiu sng di, ngi ta thy xut hin hin tng quang c ch c th lm to cht hoc lm gim ng k nng sut nui trng. (ng nh Kim, ng Hong Phc Hin, 1998). Theo Charenkova C.A (1977) th thi gian chiu sng cng di th nng sut to Spirulina cng cao. Nng sut to t cao nht khi chiu sng lin tc. Nh vy to Spirulina khng c chu k quang. (trch dn bi Nguyn Thanh Bch Ngc, Nguyn Hng Hnh, 1997).

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2.3.2 Nhit Nhit mi trng lun l mt trong nhng yu t nhy cm nh hng n bt k sinh vt no. Trong iu kin phng th nghim sinh trng ca Spirulina t ti u nhit 35 37oC. ( ng nh Kim, ng Hong Phc Hin, 1998). Nhit mi trng nui l yu t cn p ng lin tc, v rt d b chi phi v tc ng bi iu kin xung quanh, mc v thi gian chiu sng. Do vy nhit l mt trong nhng yu t thng xuyn c theo di trong cng ngh nui trng vi to. C mt mi lin h gia nhit v nh sng trong qu trnh nui cy to. Ging nh hai mt i lp ca mt qu trnh thng nht, chng u ng vai tr quan trng quyt nh n nng sut v sinh khi ca Spirulina. Sinh trng ca to t cao nht vi mt cng v thi gian chiu sng thch hp, km theo n l mt ch nhit tng i n nh. 2.3.3 Thng s pH Trong mi trng nui Spirulina pH l kt qu ca cn bng: CO2 H2CO3 H+ + HCO32H+ + CO32V vy pH c coi l yu t ch th, phn nh cc thnh phn nui dng cung cp cho mi trng nui dng to, ch yu l ngun bicarbonat v kh CO2 ho tan. (L nh Lng, 1999). Theo Trn Vn Ta v Nguyn Hu Thc (1993) th S. Platensis tng trng ti ho pH 9 11 ; pH = 9 ti ho cho s hp thu carbon ghi du phng x v s phng thch oxygen quang hp. (trch dn bi L Th Phng Hng, 1996). 2.4 Thnh phn ho hc ca Spirulina platensis Theo Clement (1975), to Spirulina cha hm lng protein rt cao, cao hn to Cholorella. Ngoi ra chng cha y cc vitamin. (trch dn bi Nguyn c Lng, 2002).

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Bng 2. 1 : Thnh phn ho hc ca to Spirulina S th t Thnh phn Protein tng s Glucid Lipid Axit nucleic Dip lc Caroten Tro S lng (% cht kh) 1 2 3 4 5 6 7 60 - 70 13 16 78 4,29 0,76 0,23 4 5

Bng 2. 2 : Thnh phn vitamin ca to Spirulina S th t Thnh phn S lng (% tng cht kh) 1 2 3 4 5 6 7 8 9 Vitamin B12 beta-Caroten D-Ca- panthothenate Axit folic Inositol Niacin (B3) Vitamin B6 Vitamin B1 Vitamin E 1,6 1.700 11 0,5 3,5 118 3 55 190

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Bng 2. 3: Thnh phn khong ca to Spirulina S th t Thnh phn S lng (% tng cht kh) 1 2 3 4 5 6 7 8 9 Canxi Photpho St Natri Clo Magie Mangan Kali Saten 1.150 8.280 528 344 4.200 1.663 22 14,4 0,4

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Bng 2. 4 : Thnh phn axit amin ca to Spirulina S th t Thnh phn g/10g S lng (% tng cht kh) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 Isoleucin Leucin Lysin Methionin Phenilalanin Theonin Tryptophan Valin Alanin Arginin Axit aspartic Cystin Axit Glutamic Glycin Histidin Prolin Serin Tyrosin 350 540 290 140 280 320 90 400 470 430 610 60 910 320 100 270 320 300 5,6 8,7 4,7 2,3 4,5 5,2 1,5 6,5 7,6 6,9 9,8 1,0 14,6 5,2 1,6 4,3 5,2 4,8

2.5 Vai tr, v tr ca to Spirulina trong cng ngh sinh hc(CNSH) Cng ngh sinh hc (Biotechnology) thuc phm tr sn xut, l nhng qu trnh cng nghip vi vic s dng c th sng (vi sinh vt,...) hoc t bo sng trong mi trng nui cy v.v... to ra nhng sn phm c ch cho x hi. Cng ngh sinh hc c in to ra ri, bia, chao, tng...; cn cng ngh sinh hc hin i to ra thuc

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men, vitamin, acid amin cht lng cao, cht do t vi sinh, v c th c hng cu mu nhn to v.v... Trong t nhin vai tr ca gii to (Algae) ni chung, nht l to bin vi vai tr quang hp gn gi cacbonic to ra khong 500 t tn cht hu c c th s dng c (trong c nhiu hot cht sinh hc qu) v thi ra 90% lng oxy trong bu kh quyn cn cho s h hp ca ngi v ng vt. Chnh iu ny kch thch ngh nui to bin ra i, v c bit xut hin cng ngh sinh hc vi to, vi b 3 ni ting Chlorella, Scenedesmus v Spirulina, c nhiu gi tr trong thc phm dinh dng v dc phm, m phm. Trong cng ngh sn xut sinh khi vi sinh vt (Microbial biomass products), ring nhm 3 vi sinh vt to trn, Spirulina hin c chn pht trin sn xut hn 2 loi kia do 5 u th sau :

Hiu qu kinh t cao v gp phn bo v, ci thin mi trng : Vi to

Spirulina khng nhng n gin trong nhu cu dng cht m cn rt hiu qu trong s dng nng lng nh sng mt tri, nc... (c th dng nc bin, nc l, nc mn,...); gn gi carbon tt (6,3 tn/ha/nm); ng thi to ra 16,8 tn oxy...iu ny gip cho nh sn xut thu hoch c li ch kinh t ln hn so vi vi to khc v gip bo v mi trng kh quyn, gm nh hiu ng nh knh (green house).

Gi tr s dng vt ra khi ranh gii truyn thng dng lm thc

phm, nh c tc dng cha bnh mi pht hin, sn xut thnh mi trng nui cy t bo ngi, ng vt, s dng lm m phm v.v...

Tham gia vo vic x l mi trng : ngoi vic cung cp dng kh oxy,

Spirulina cn c kh nng gn gi mnh cc cation c nh ch, thu ngn, cadmi,... nn c th dng x l cht thi lng, x l nc. Sinh khi ny s dng lm cht t, c bit thay cho du diesel, nu thnh cng th l iu cng lm tng gi tr ca Spirulina.

Spirulina c th l i tng chuyn ti cc tin b khoa hc k thut rt Nui nh hng gn gi cc cht c li cho dinh dng v tr bnh

hin i trong cng ngh sinh hc :

cho ngi v ng vt. c cc tin b v nui cy Spirulina gn Iod (phng tr bnh

20

thiu vi cht iod)., gn Selen, gn Germani (cht chng oxy ho, chng lo ho, phng chng ung th...)v.v... Hoc nui vi nhng tin cht nh hng cho sinh khi Spirulina giu acid bo cn thit, giu beta-caroten. S thnh cng trong tng lai ph thuc vo vic chn ging Spirulina v tm ti cng ngh ph hp, s cho nhng l/m sinh khi Spirulina rt c gi tr trong y dc.

Spirulina vi cng ngh chuyn np gen: Chuyn np gen l k thut

phn lp gen t c th cho (donor), cy ghp vo b my di truyn ca c th nhn (receiver), nhm to ra tnh trng mi cn thit t c th . K thut tn tin ny ang c nghin cu vi Spirulina 2 hng sau : * Chuyn gen chu trch nhim di truyn to phao kh ca Spirulina gip vi sinh vt ni trn mt nc d dng. Ta bit mun phng tr bnh st rt phi dit mui Anopheles stopenis, bnh st xut huyt phi dit mui Aedes aegypti, bnh giun ch phi dit mui Culex quinquefasciatus. Mt cch hiu qu ct t vector truyn bnh ny l dit u trng (b gy, lng qung...) ca chng. Hin mt s nghin cu cho thy c nhng vi sinh vt, hoc vi nm c th thc hin c iu ny. Tuy vy vic phi sng tri ni trn mt nc (mi trng u trng cc loi mui gy bnh sinh sng), dit u trng mui li l im khng c hoc yu km ca cc vi sinh vt ny. Do vy c th tch gen di truyn to phao kh ni trn mt nc ca Spirulina ghp vo vi sinh vt c ch trn, to ra nhng c im mong mun dit u trng mui gy bnh. * Chuyn np gen to cht do sinh hc cho Spirulina : c th ghp vo Spirulina gen to cht polyhydroxyl butylat (P.H.B), gen ny c vi khun Aleutroplus, to ra ging Spirulina mi c c tnh pht trin sinh khi nhanh, ng thi cha P.H.B vi hm lng thch hp. Ly trch cht P.H.B sn xut nha thay th nha do (nh poly styrene) v cht do mi ny d b phn hu khng lm nhim mi trng v.v...

Spirulina tng i thch nghi vi mi quy m sn xut : c th thu hoch

t t nhin, hoc nui quy m nh (h gia nh, lng x), trong iu kin bn t nhin, vi k thut n gin nh nui trng thu sn. quy m cng nghip (ngoi vic chuyn ti cc k thut sinh hc rt hin i nu trn), Spirulina cn thch hp vi trnh

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cng ngh t k thut nui b mt c in n k thut nui 3 chiu rt hin i. Cn k ra nhiu u im khc nh d thu hoch do dc tnh ni trn mt nc, v kch thc ln (di 0,25 - 0,5 mm), nn d vt, lc v.v...(L nh Lng, 1999). 2.6 Mt r (hay r ng) Mt r l th liu trong cng ngh sn xut ng t cy ma hay c ci ng. Trc y mt r t c s dng trong cng ngh vi sinh. Sau ny ngi ta thy mt r c nhiu u im to mi trng nui cy vi sinh vt. Nhng c tnh quan trng ph hp vi qa trnh ln men ca mt r bao gm : Cha hm lng ng cao Ngoi ng saccharose ra cn cha nhiu cht hu c, v c, cc cht

thuc vitamin v cc cht kch thch sinh trng, trong c vitamin H (Biotin) l cht kch thch sinh trng i vi phn ln nm men.-

Tuy nhin, r ng cng c nhng c im khng ph hp cho qu trnh

ln men. Mun s dng chng cho qu trnh ln men i hi phi c cc qu trnh x l thch hp. Cc c im cn lu mt r bao gm : R ng thng c mu sm. Mu ny kh b ph hu trong qu

trnh ln men. Sau ln men chng s bm vo sinh khi vi sinh vt v bm vo sn phm. Vic tch mu ra khi sinh khi v sn phm thng rt tn km v rt kh khn. Gia hai loi mt r, loi mt r t cy ma c mu sm hn mu mt r nhn t sn xut c ci phi x l trc khi tin hnh qu trnh ln men. Hm lng ng kh cao (thng nm trong khong 40

50%).Lng ng ny ch yu l saccharose nn khi tin hnh ln men phi pha long ti nng thch hp. c im gy kh khn ln nht cho qu trnh ln men l h keo trong

mt r. Keo cng nhiu, kh nng ho tan oxy cng km v kh nng trao i cht ca oxy cng km. Do cng vic quan trng nht khi s dng mt r l phi ph h keo ny.

22 V r ng l cht dinh dng kh l tng nn chng ry d b vi

sinh vt xm nhp v pht trin. Nh vy cht lng mt r cng d thay i theo thi gian bo qun. Bng 2. 5: Thnh phn ho hc v mt s tnh cht quan trng ca hai loi mt r STT Thnh phn ng tng s Cht hu c khc Protein (Nx6,25) K Ca Mg P Biotn (vitamin H) Axit pantotenic Inozitol Tiamin n v tnh Hm lng mt r C ci 1 2 3 4 5 6 7 8 9 10 11 % % % % % % % mg/kg mg/kg mg/kg mg/kg 48 52 12 17 6 10 27 0,1 0,5 0,09 0,02 0,07 0,02 0,150 50 110 5000 8000 1,3 ng ma 48 56 9 12 24 1,5 5 0,4 0,8 0,06 0,6 0,2 13 15 55 2500 6000 1,8

gii quyt nhng c im khng thun li c trong mt r i vi qu trnh ln men, ngi ta thng s dng axit sunfuric m c vi lng 3,5 kg cho mt tn mt r. Khi cho H2SO4 vo mt r, ta c ba cch thc hin qu trnh x l ny : Cch th nht : Khi cho 3,5 kg H2SO4 vo mt tn mt r, ngi ta khuy u nhit thng trong thi gian 24h, sau ly tm dch trong . Cch th hai : Khi cho 3,5 kg H2SO4 vo mt tn mt r, ngi ta un ton b ln 85oC v khuy u lin tc trong 6h, sau ly tm thu dch trong. Cch th ba : Cho H2SO4 n khi pH ca mt r t c gi tr l 4, ngi ta un nng n 120 125oC trong mt pht cc cht v c kt ta, sau ly tm thu dch trong.

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Thc hin mt trong ba cch trn s thu c dch mt r loi th keo v mu. T mt r qua x l ny em pha ch thnh cc loi mi trng c nng khc nhau. V d mi trng nui cy thu nhn sinh khi, nng ch cn 2 4 %. Trong khi mi trng ln men cn hoc axit hu c, nng ng li t 16 22 %. Tuy nhin gi tr ca mt r trong qu trnh nui cy nm men thu nhn sinh khi khng ch do lng ng saccharose c trong mt r m cn do cc loi mui khong, cc cht kch thch sinh trng v cc thnh phn khc quyt nh. (Nguyn c Lng, 2002) 2.7 Cc kiu thit b ln men c th ng dng trong nui to Thit b ln men ng vai tr quan trng trong cng ngh vi sinh vt. y l mt lnh vc rt phc tp v nhiu trng hp thay i thit b ln men hp l s thu c kt qu ln men rt tt. Vic thit k ch to thit b ln men c nh hng rt ln n qu trnh sinh l ca sinh vt. Chng ta phi hiu rng vic chuyn mt ging vi sinh vt t ging gc c phn lp t iu kin t nhin sang qu trnh sn xut cng nghip tri qua hai giai on c tnh quyt nh n sinh l ca vi sinh vt : 1Giai on t iu kin t nhin khng kim sot sang iu kin nui cy trong phng th nghim v sn xut th vi cc yu t nh hng ti sinh l ca vi sinh vt hon ton c kim sot. 2Giai on t iu kin c kim sot mc nh trong phng th nghim sang giai on sn xut ln vi qui m ln. Cc thit b ln men vi chc m3 n hng ngn m3. Khi mi yu t nh hng n sinh l ca vi sinh vt hon ton khc vi iu kin trong phng th nghim. V d, s truyn nhit thit b phng th nghim khc s truyn nhit thit b sn xut, p xut v kh nng ho tan ca oxy cng khc. 2.7.1 Thit b c cnh khuy Cc thit b c lp t cnh khuy u c ng dng trong qu trnh ln men hiu kh cng nh ln men ym kh. Cnh khuy trong hai trng hp ny c tc dng nh sau :

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1- Cc khuy lm tng kh nng tip xc cht dinh dng v t bo vi sinh vt. C tip xc gia cht dinh dng vi t bo vi sinh vt mi c s trao i cht. Kh nng tip xc cng nhiu, kh nng trao i cht cng mnh. Do c hai phng php ln men hiu kh v k kh u cn c cnh khuy. S tip xc ny c th c thc hin t nhng v tr xa nhau gia cht dinh dng v vi sinh vt. V d, t bo vi sinh vt v tr rt xa cht dinh dng, nhng do cnh khuy hot ng, c t bo v cht dinh dng s chuyn ng nn iu kin v c hi gp nhau l rt ln. S tip xc ny cn biu hin ch, trong khi tin hnh cc qu trnh trao i cht, cc cht sau ng ho v d ho s to ra mt lp bao quanh t bo. Lp bao quanh t bo ny s lm cn tr s chuyn vn cc cht vo t bo. Khi cnh khuy hot ng, lp bao quanh ny s b ph b, nh vy mc xm nhp ca cc cht dinh dng s mnh hn. 2- Trong trng hp ln men trong iu kin hu kh cnh khuy lm tng kh nng ho tan ca oxy. Cc kh s li lu hn do dng chuyn ng ca mi trng, v nh vy kh nng ho tan ca oxy t bt kh s cao hn. Cnh khuy lm tng kh nng tch cc kh CO2, H2S, NH3,...t qu trnh trao i cht, v nh vy s lm gim nh hng xu ca cc loi kh ny n sinh l ca vi sinh vt. 3- Cnh khuy lm tng nhanh cc qu trnh sinh sn ca vi khun nm men v nm si : do tc ng c hc m cc t bo d dng tch ra v sng c lp. Trong phng th nghim, ngi ta thng thay cnh khuy bng nhng my lc. Nhng thit b c dung tch trn mt lt ngi ta mi lp cnh khuy. Trong qui m sn xut cng nghip ngi ta ch s dng my khuy ch khng s dng my lc. (Nguyn c Lng, 2002). Phng php khuy c hc c thc hin bng cc cch khuy khc nhau t cc mc ch khc nhau : ho. Thc hin cc qua trnh thu c : to nh tng, huyn ph, ho tan, ng

25

- Thc hin qu trnh trao i nhit : s kt tinh, trch ly, hp th v in phn. Thc hin qu trnh nhit : c c dung dch, un nng v lm ngui. Thc hin cc phn ng ho hc. Thc hin cc phn ng sinh hc.

Nh vy khuy mi trng lng, trong pha lin tc l mt cht lng, cn pha phn tn c th l : pha lng, pha rn, hoc pha kh. Khuy cht lng l cung cp nng lng to mt dng chy thch hp trong thit b nhm p ng cc mc tiu ni trn. Qu trnh khuy c th thc hin trong thit b gin on hoc thit b lin tc theo yu cu sn xut ca mt cng ngh sn xut c th. iu kin ca mt mi trng khuy trn c xc nh bi nhit , p sut v nng pha phn tn. Do vy thit b khuy c th thc hin dng kn hay dng h. Thit b khuy thng c ch to dng tr thng ng, tuy nhin cng c trng hp p dng thit b khuy nm ngang. (Nguyn Vn La, 1999). Trong nui trng i tr vi to, vic khuy sc c tc dng : Ngn nga hin tng phn tng nhit trong dch nui. Gip t bo to tip xc u n vi nh sng. Ngn nga to lng xung y b. Gip phn phi dinh dng v CO2. Nh vy k thut khuy sc l vn rt cn c quan tm nhm mc tiu tng nng sut to m khng lm nh hng ti trng thi t bo. V mt kinh t, chn gii php khuy sc cho chi ph thp nht l yu cu u tin. (ng nh Kim, ng Hong Phc Hin, 1999). Trn to l ngn cn s lng t, s phn tng nhit v nhng iu kin ym kh y. S khuy trn gip cht dinh dng tip xc tch cc vi b mt to v lm tng nng sut to. i vi th tch nh, s khuy to thng tin hnh bng cch to bt kh qua ci lc. Khng kh c cha vi phn trn CO2, s gi gi tr pH khong 8 v trnh nhng iu kin hn ch CO2.

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Vi qui m ln, nhiu k thut trn c pht trin ch yu l x l nc thi cha to hoc sn xut cc loi n bo, nhng k thut dng cho n nay l bnh xe quay, bm kh v bm ln. H thng bnh xe quay thch hp hn cho nui mi trng cn., thng to kh vi mi trng nui su (di 2 m). Bm kh cng rt hu hiu v s dng bm mnh khuy trn mi trng nui to quy m ln. Theo kinh nghim, vi n v nui su100 m2, su 1m th khuy 5 pht/gi dng nh ngn cn phn tng nhit v cung cp dinh dng cho ton b khi nc. (Nguyn Thanh Tng, 1998). 2.7.2 Thit b c h thng thi kh Thit b c h thng thi kh c lp p trong cc thit b ln men c nhng tc dng sau : 1- Cung cp oxy trong cc trng hp ln men hiu kh, c bit l qu trnh thu nhn sinh khi (nm men, nm si hay vi khun). 2- Cung cp CO2 trong trng hp nui cy to n bo (Chlorella, Spirulina, Scenedesmus). 3- Khuy o mi trng lm tng qu trnh trao i cht, qu trnh pht trin v qu trnh sinh sn. 4- Gii phng cc kh c to ra t qu trnh trao i cht, lm gim nh hng xu n qu trnh ln men. Vic cung cp oxy hay CO2 cho qu trnh ln men l mt vic lm ht sc phc tp. Trong khng kh, ngoi cc thnh phn ca khng kh cn cha rt nhiu vi sinh vt, do khng kh cung cp cho qu trnh ln men i hi phi c sch s v vi sinh vt v cc tp cht. (Nguyn c Lng, 2002).

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PHN III : VT LIU V PHNG PHP3.1 a im v thi gian tin hnh ti a/ a im: Phng th nghim 305 khu phng v trng i hc Nng Lm TP.HCM b/ Thi gian tin hnh ti : t 01-03-2006 n 30-06-2006 3.2 Vt liu 3.2.1 Ngun to ging To Spirulina platensis c cung cp t c s nui HELVINAM 3.2.2 Ho cht a/ Mi trng Zarrouk l mi trng ho cht c bn cung cp cc thnh phn dinh dng thit yu cho Spirulina : Bng 3. 1: Thnh phn mi trng Zarrouk STT 1 2 3 4 5 6 7 8 b/ Mi trng r ng R ng sau khi qua x l mu bt u tin hnh pha mi trng nui cy Spirulina, thnh phn bao gm: Tn thnh phn NaHCO3 NaNO3 NaCl K2HPO4 K2SO4 MgSO4.H2O CaCl2.H2O EDTA Fe Khi lng 16.8 g/l 2.6 g/l 1.0 g/l 0.5 g/l 1.0 g/l 0.2 g/l 0.04 g/l 0.08 g/l

28

Bng 3. 2 : Thnh phn cc mi trng r ng STT 1 2 Tn thnh phn R ng NaHCO3 Khi lng 1; 1.5 16.8 n v tnh ml /L G/L

3.2.3 Dng c th nghim Chai nc bin 500 ml Knh hin vi Khc x k n hunh quang My sc kh n cn Giy qu Autoclave T sy Bnh tam gic 1 L Bnh nha 5 L, 10 L, 21 L B knh 40 L Dy din, pipt,...

3.3 Phng php nghin cu 3.3.1. Phng php b tr th nghim 3.3.1.1 Th nghim 1 : nh hng ca nng nui cy ln kh nng thu hoch to Spirulina Th nghim n yu t c b tr theo kiu hon ton ngu nhin gm ba nghim thc, mi nghim thc c tin hnh nui trong 3 chai nc bin, v tin hnh lp li 3 ln. Kho st nh hng ca nng nui cy ban u ln kh nng thu hoch to Spirulina. Cy 20 %, 25 %, 30 % to ging Spirulina vo 300 ml mi trng c bn

29

(Zarrouk) trong chai nc bin 500 ml. Sau 7 ngy nui cy tin hnh thu hoch to bng li lc v cn trng lng to ti (mi chai nc bin ly mt mu to ti). iu kin nui cy c gi n nh : nhit phng nui : 34 37oC, pH = 8 11, th tch mi trng nui cy 300 ml, tc sc kh 500 ml/ pht, cng nh sng 3000 3500 lux, chiu sng lin tc 24/24. Mi trng nui cy v dng c nui c hp kh trng bng autoclave 1 atm trong 30 pht. 3.3.1.2 Th nghim 2 : nh hng ca ch chiu sng ln s tng sinh khi to Spirulina Th nghim n yu t c b tr theo kiu hon ton ngu nhin gm ba nghim thc, mi nghim thc c tin hnh nui trong 3 chai nc bin, v tin hnh lp li 3 ln. Kho st ch chiu sng ti kh nng tng sinh khi ca to Spirulina. Cy 30 % to ging Spirulina vo 300 ml mi trng trong chai nc bin 500 ml nui trong cc iu kin chiu sng khc nhau : 1500 1750 lux, 3000 3500 lux, 4500 5250 lux. Sau 7 ngy nui cy tin hnh thu hoch to bng li lc v cn trng lng to ti (mi chai nc bin ly mt mu to ti). iu kin nui cy c gi n nh trong sut qu trnh nui cy: nhit phng nui : 34 37oC, pH = 8 11, th tch mi trng nui cy 300 ml, tc sc kh 500 ml/ pht, th tch to ging 30%, chiu sng lin tc 24/24. Mi trng nui cy v dng c nui c hp kh trng bng autoclave 1 atm trong 30 pht. 3.3.1.3 Th nghim 3 : nh hng ca khi lng mui bicarbonat trong mi trng nui cy ln s tng sinh khi to Spirulina : Th nghim n yu t c b tr theo kiu hon ton ngu nhin gm ba nghim thc, mi nghim thc c tin hnh nui trong 3 chai nc bin, v tin hnh lp li 3 ln. Kho st nh hng ca mui bicarbonat ln s tng sinh khi to Spirulina. Cy 30% to ging Spirulina vo 300 ml mi trng nui cy trong chai nc bin 500 ml cc iu kin mi trng c cha 16; 16,8; 17 g NaHCO3. Sau 7 ngy nui cy tin

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hnh thu hoch to bng li lc v cn trng lng to ti (mi chai nc bin ly mt mu to ti). iu kin nui cy c gi n nh : nhit phng nui : 34 37oC, pH = 8 11, th tch mi trng nui cy 300 ml, tc sc kh 500 ml/ pht, cng nh sng 3000 3500 lux, chiu sng lin tc 24/24. Mi trng nui cy v dng c nui c hp kh trng bng autoclave 1 atm trong 30 pht. 3.3.1.4 Th nghim 4 : nh hng ca cc mi trng nui cy khc nhau ln s tng sinh khi to Spirulina: Th nghim n yu t c b tr theo kiu hon ton ngu nhin gm ba nghim thc, mi nghim thc c tin hnh nui trong 3 chai nc bin, v tin hnh lp li 3 ln. Kho st nh hng ca cc loi mi trng nui cy khc nhau ln s tng sinh to Soirulina. Cy 30 % to ging Spirulia vo 300 ml mi trng trong chai nc bin 500ml nui trong cc iu kin mi trng khc nhau bao gm : mi trng 1 : mi trng c bn (Zarrouk), mi trng 2 : mi trng 1 ml r ng + 16,8 g NaHCO3, mi trng 3 : mi trng 1.5 ml r ng + 16,8 g NaHCO3. Sau 7 ngy nui cy tin hnh thu hoch to bng li lc v cn trng lng to ti (mi chai nc bin ly mt mu to ti). iu kin nui cy c gi n nh : nhit phng nui : 34 37oC, pH = 8 11, th tch mi trng nui cy 300 ml, tc sc kh 500 ml/ pht, cng nh sng 3000 3500 lux, chiu sng lin tc 24/24. Mi trng nui cy v dng c nui c hp kh trng bng autoclave 1 atm trong 30 pht. 3.3.2 Phng php theo di ch tiu cht kng mi trng nui cy v iu kin nui cy to Spirulina Trong sut qu trnh nui cy tin hnh theo di mt s yu t mi trng nui cy : Kim tra pH bng giy qu. Kim tra nhit phng nui bng nhit k.

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-

Kim tra cng chiu sng bng lux k.

3.3.3 Phng php x l s liu S liu thu c c x l bng phn mm excel v stagraphic 7.0. 3.4 Thit k my khuy dung tch nh 40 50 l My khuy dung tch nh vi cc thng s sau : Tc vng quay t 10 20 vng/ pht. Khuy trong mi trng dch lng cha to. Th tch bnh cha t 20 50 l ng knh cnh khuy t

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PHN IV : KT QU V THO LUNCc nh khoa hc trn th gii ang n lc trong cng vic tm kim cc ngun nguyn liu mi, sch v m bo cht lng thay th dn cc ngun nguyn liu c. To c th l mt trong nhng ngun nguyn liu cho ngnh lng thc thc phm mi, n khng nhng cha y cht dinh dng m cn l mt trong nhng dc liu qu n t thin nhin. c bit l Spirulina, chng d dng trong cng vic nui cy, kh nng thu hoch sinh khi cao, c trong thao tc thng thng n nhng k thut trong phng th nghim u c kh nng p dng trn i tng ny. T nhng cng vic pha ch mi trng c bn cha cc thnh phn ho hc phc tp (Zarrouk) n nhng mi trng nhn to n gin u c th s dng nui Spirulina. Hon thin dn cc quy trnh kho st vic tng sinh khi Spirulina trong phng th nghim, nng cao cc hiu sut ca cc cng on c th tng sinh khi to ny qui m cng nghip. 4.1. Cc th nghim tng sinh khi to 4.1.1 Mt s yu t l ho nh hng n th nghim kho st tng sinh khi Spirulina Ging nh cc vi sinh vt thng thng, theo quy lut pht trin vi sinh vt ni chung, to ni ring u chu s nh hng, tc ng bi s tham gia ca cc yu t l cng nh ho hc. Trong qu trnh b tr cc th nghim tng sinh khi to mt s thng s l ho c theo di ch yu c trnh by bng di :

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Bng 4. 1 : Mt s yu t l ho trong qu trnh nui cy: Ln V tr b tr th nghim 1 Phng th nghim 2 Phng th nghim 3 Phng th nghim 4.1.1.1 Nhit Nhit nh hng ln tt c cc qu trnh sinh sng ca c th thc vt ni chung v ca to Spirulina ni ring. nhit thp quang hp ca to tng i km, cng quang hp tng theo s tng ca nhit . Tuy nhin vic tng cao nhit ln qu nhit ti thch ca to s lm gim st quang hp v dn n ngng hn quang hp. V nhit ti u i vi sinh trng ca to theo cc tc gi n dao ng trong khong 34 35oC, nhng theo kt qu nghin cu ca Vin sinh vt, Vin khoa hc Vit Nam nhit ti thch cho s pht trin ca to l 32oC. (Nguyn Anh Dng, 1982). Trong qu trnh b tr th nghim theo kt qu kho st v theo di, nhit phng th nghim dao ng t 34 37oC, to pht trin mnh, sinh khi t nhiu. Nh vy kt qu ghi nhn c v nhit trong c qu trnh thc hin phng th nghim l ph hp cho s sinh trng, pht trin tng nng sut sinh khi to. 4.1.1.2 pH Theo Ciferri and Tiboni (1985), trong cc h c nng mui cao (c bit l carbonat sodium c ngun gc trm tch ni la), th d cc h thuc ng Phi, nc rt kim, pH 9,4 11, S. platensis hin din mt cch u th. Do tnh kim ca mi trng tng trng, s nhim khum trong dch nui cy Spirulina thp hn so vi to 34 37oC 8 11 35 37oC 8 11 34 37oC 8 - 11 Nhit (oC) pH Tc sc kh 500 ml/pht 500 ml/pht 500 ml/pht

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nui cy chn hch hay t bo thc vt bc cao vi pH acid. (trch dn bi L Th Phng Hng, 1996). To Spirulina thng sng t nhin vng nc giu NaHCO3 v c pH = 8,5 11. Vi gi tr pH cao nh vy rt thun li cho vic np CO2 vo mi trng nui cy.(Nguyn Anh Dng, 1982). Trong nui to lc xut pht thng s dng mui bicarbonat vi pH hi thp (khong 8 8,5) sau pH tng ln theo chiu phn ng to OH-, pH kim thch nghi vi Spirulina nn hiu qu ca gn gi CO2 tt hn so vi nui to chlorella ( pH trung tnh hoc acid), l mt li th ca Spirulina. (L nh Lng, 1999). Tuy vy, s nhim khun khng phi khng xy ra, rt l trong cc ao nui cy h (open pond culture), nu cc si to khng c ra nhiu ln vi dung dch sinh l v trng (kt hp vi s lc hay ly tm). Nu dng to lm thc phm, s nhim khun trn to s gy nguy him cho sc kho con ngi. (L Th Phng Hng, 1996). Vic b tr th nghim vi thng s pH ghi nhn c t 8 11 trong sut thi gian nui cy nh vy l rt thch hp cho Spirulina platensis pht trin. 4.1.1.3 Tc khuy sc Mt iu ng ch l tc khuy trn nh hng n mt ti u ca to trong dung dch. Trong iu kin t nhin ca ma h c chiu sng cao, khi nui khng c khuy trn mt to nhn ban u tt nht l t 0,8 1,1 g/l, trong iu kin nui theo phng php bn cng nghip c sc kh CO2 mt to c th gi l 0,5 3 g/l. (Nguyn Anh Dng, 1982). Trong iu kin thc hin vic kho st cc nh hng phng th nghim tc sc kh o c l 500 ml/pht, c th l ph hp cho nui cy to mt lng dung tch nh. V vy khi nui qui m ln hn cn kho st thm tc ng ca h thng sc kh v khuy trn i vi tc tng trng ca Spirulina. 4.1.2 nh hng ca cc phng php gy nui khc nhau ln s gia tng sinh khi, thu hoch to Spirulina platensis C th ni Spirulina l mt trong nhng i tng c coi l c tim nng, bi nhng u im ni tri hn so vi cc loi khc nh,d nui,d thu sinh khi, phc v

35

cc mc ch nghin cu t khoa hc c bn n khoa hc ng dng thc tin cao. V vy cc th nghim p dng trn i tng ny rt nhiu, ngi ta pha ch cc mi trng nhn to khc nhau vi cc thnh phn n gin d kim m y cc dng cht nhm tng sinh khi ca Spirulina. Ngoi ra ngi ta cn kch thch nhiu bin php nhm tng sinh khi ca to cc phng din khc nhau, t tm ra cc im ti u trong cc iu kin nh v nhit , nh sng, tc khuy sc mi trng... ph hp vi iu kin nui trng rng ri tng ni. Qua kho st nhn thy v c im nui trng Spirulina chng ta d dng nhn ra nh hng ca cc iu kin nui cy l mt trong nhng vn cn quan tm trong vic tng sinh khi. iu kin nui c th phi c ch v quan tm nhiu hn bao gm cc thnh phn dng cht trong mi trng nui cy, nhit , nh sng pH,... khi xem xt cn c bit tm hiu nh hng tc ng ring cng nh cng gp ca cc nhn t trn trong qu trnh nui cy to Spirulina. Spirulina cng l mt trong nhng loi kh nng thu hoch cao v d dng. Ngi ta c th thu hoch chng bng cc bin php ly tm, lng, ta vi ho cht... n cc phng php n gin cng c th thc hin c, nh phng php dng cc vi lc hay li lc vi ng knh l lc ph hp c th thu c mt lng to theo mun. Tuy nhin iu ng quan tm hn c trong vic nui tng sinh khi Spirulina l khi thu hoch mt lng to ti, thng phn nc cn li trong mi trng nui c tnh nht ca kim rt cao, to thng c mi tanh rt nng. Kh nng tn ti mt lng d tha no ca cc mui kim loi mang tnh baz trong to cng nh trong mi trng nc cn li l rt cao, nh hng ti nhim mi trng. V vy vn t ra nu dng to vo lm ngun thc phm cho ngi v ng vt th cn phi gim c cc nh hng nu trn.

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Hnh 4. 1: S nhn sinh khi Spirulina t ngun to ging ban u Quy trnh nhn nhanh sinh khi ca Spirulina c miu t hnh 4.1 l : t lng to ging ban u nui trong bnh tam gic 250ml, sau thc hin cc ln cy chuyn, nui trong bnh tam gic 500ml hoc chai nc bin 500 ml chuyn sang nui trong bnh tam gic 1L, nhn sinh khi ri cy sang bnh nha 5L. Thu nc to bnh nha 5L ri chuyn sang nui trong cc th tch cha ln nh 10L, 20L,ta s thu c lng sinh khi to theo mong mun. 4.1.2.1 Th nghim 1 : Th nghim nh gi nh hng ca nng nui cy ban u ln kh nng thu hoch to kho st nh hng ca nng nui cy ban u ln kh nng thu hoch to, tin hnh cy to ging Spirulina platensis ba nng khc nhau 20%, 25%, 30% vo 300 ml mi trng dinh dng c bn (Zarrouk). Th nghim c thc hin lp li ba ln, mi nghim thc tin hnh nui trong 3 chai nc bin. Sau 7 ngy nui cy tin

37

hnh thu hoch bng li lc v cn trng lng ti (mi chai nc bin ly mt mu to ti).

Hnh 4. 2 : To ging c tr trong iu kin lnh trc khi em ra tin hnh cc th nghim.

Hnh 4. 3 : To nui trong th nghim 1 ngy th 5

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Bng 4. 2: Trng lng to ti thu c sau 7 ngy nui cy (S g to ti/1Lmi trng) th nghim 1 t TN t I t II t III 10 7 13 20 % 13 10 10 10 10 7 13 13 10 Nng to cy ban u 25 % 13 13 17 17 17 10 17 17 17 30% 13 17 17 17 17 20

Nhn chung, trng lng to ti tng dn theo chiu tng ca nng , nng nui cy ban u cng cao th trng lng to ti thu hoch c cng nhiu. iu ny l ng vi quy lut v kt qu th nghim rt ph hp vi nhiu nhn nh ca cc tc gi khc. cc khong nng nui cy khc nhau, khi b sung y mi trng dinh dng v n nh iu kin nhit phng th nghim t 34 37oC, pH = 8 11, tc khuy sc 500 ml/pht, cng nh sng 3000 3500 lux, th to pht tin mnh sinh khi nhiu.

To c mu xanh nht khi nui nng 20%

To c mu xanh nht khi nui nng 25%

To c mu xanh m khi nui 30%

Hnh 4. 4 : To nui trong th nghim 1 ngy thu hoch th7

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Qua s quan st trc tip mu ca dch to trong mi trng nui phng th nghim nhn thy nng nui cy ban u 30% th mu to l xanh m hn so vi 20%, 25% to c mu xanh nht hn. Theo nghin cu ca thc s L Th Phng Hng nm 1996 th t ngy th 5 - 7 l giai on to Spirulina platensis ko di ti a si to, trong giai on ny chiu di si to t ti mc ti a. C l v vy nn trng lng to thu hoch ngy th by s c kh nng l nhiu nht so vi cc ngy khc . Theo x l s liu bng stagraphic khng nh c s khc bit v trng lng to ti thu hoch cc nng cy ban u l 20%, 25%, 30% v phng din thng k hc (P < 0,05). Cc khng bo kh gip Spirulina ni trn b mt mi trng Zarrouk

Hnh 4. 5 : Hnh thi si to Spirulina platensis quan st x400

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th 4. 1 : Biu so snh trng lng to ti thu c cc nng nui cy ban u khc nhau (20%, 25%, 30%). Nhn xt : theo biu trn th khong nng nui cy ban u l 30% th kh nng thu hoch to l nhiu nht vi chu k 7 ngy. Tm li vi iu kin nhit phng th nghim t 34 37oC, pH= 8 11, tc khuy sc 500 ml/pht, cng nh sng 3000 3500 lux th khong nng nui cy ban u l 30% kh nng thu hoch sinh khi to ti l nhiu nht, to c mu xanh m hn so vi cc khong nng 20%, 25% vi chu k thu hoch l 7 ngy. 4.1.2.2 Th nghim 2 : Th nghim nh gi nh hng ca ch chiu sng ln s tng sinh khi to kho st nh hng ca ch chiu sng ln s tng sinh khi to, tin hnh cy to ging Spirulina platensis nng 30% vo 300 ml mi trng dinh dng c bn (Zarrouk) t trong cc iu kin chiu sng khc nhau : 1500 1750 lux, 3000 3500 lux, 4500 5250 lux. Th nghim c thc hin lp li ba ln, mi nghim thc tin hnh nui trong 3 chai nc bin. Sau 7 ngy nui cy tin hnh thu hoch bng li lc v cn trng lng to ti (mi chai nc bin ly mt mu to ti).

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Bng 4. 3 : Trng lng to ti thu c sau 7 ngy nui cy (S g to ti/1Lmi trng) th nghim 2 t TN t I t II t II Cng chiu sng khc nhau 1500 1750 lux 17 17 20 17 17 20 20 13 13 3000 3500 lux 20 23 20 17 23 20 20 20 20 4500 5250 lux 23 17 17 27 17 23 20 10 23

Theo kt qu trn vi vic x l bng stagraphic th trng lng to ti thu c cc iu kin ch chiu sng khc nhau l c s khc bit v phng din thng k hc (P < 0,05). V gia cc ch chiu sng khc nhau 1500 1750 lux vi 3000 3500 lux, 3000 3500 lux vi 4500 5250 lux, hay 1500 1750 lux vi 4500 5250 lux th trng lng to ti thu c cng c s khc nhau.

To c mu xanh m

Hnh 4. 6 : To Spirulina platensis nui ngy th 5 trong iu kin nh sng t 3000 3500lux

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To c mu xanh nht

Hnh 4. 7: To nui iu kin nh sng 1500 1750 lux trong ngy 1 ca th nghim

To c mu xanh m

Hnh 4. 8 : To nui iu kin nh sng 1500 1750 lux trong ngy 5 ca th nghim To lam c th sinh trng tt trong iu kin chiu sng t 1000 4500 lux.( Nguyn Anh Dng, 1982). Trong th nghim b tr kt qu thu c khng nh Spirulina c th sng sinh trng v pht trin c khi cng nh sng cheu t

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1500 5250 lux. iu ny l tng i ph hp vi nhn nh ca cc tc gi nhau trong iu kin phng th nghim.

th 4. 2 : Biu so snh trng lng to ti thu c iu kin cng chiu sng khc nhau (1500 1750 lux,3000 3500 lux,4500 5250 lux). Nhn xt : nhn vo biu ta thy iu kin chiu sng 1500 1750 lux v 3000 3500 lux th trng lng to ti thu c l tng i n nh hn so vi nghim thc cn li 4500 5250 lux qua ba t th nghim. Theo mt s kin ca cc nh khoa hc th to Spirulina platensis sinh trng mnh iu kin chiu sng t 3000 3500 lux.V nhn chung kt qu th nghim thu c cng khng nh to Spirulina platensis pht trin mnh t sinh khi nhiu v n nh iu kin chiu sng t 3000 3500 lux, trong iu kin nui phng th nghim vi cc thng s nhit phng 34 37oC, pH = 8 11, tc khuy sc 500 ml/pht. 4.1.2.3 Th nghim 3 : Th nghim nh gi nh hng ca khi lng mui bicarbonat trong mi trng nui cy ln s tng sinh khi to Spirulina kho st nh hng ca khi lng mui bicarbonat trong mi trng nui cy ln s tng sinh khi to Spirulina, tin hnh cy to ging Spirulina platensis nng 30% vo 300 ml mi trng dinh dng c bn (Zarrouk) t trong cc iu

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kin mi trng cha 16g NaHCO3 , 16,8g NaHCO3, 17g NaHCO3. Th nghim c thc hin lp li ba ln, mi nghim thc tin hnh nui trong 3 chai nc bin. Sau 7 ngy nui cy tin hnh thu hoch bng li lc v cn trng lng to ti (mi chai nc bin ly mt mu to ti). Bng 4. 4 : Trng lng to ti thu c sau 7 ngy nui cy (S g to ti/1Lmi trng) th nghim 3 t TN t I t II t III Kt qu thu c chng t Spirulina u c kh nng sinh trng v pht trin tt trong cc iu kin mi trng c cha 16g NaHCO3 , 16,8g NaHCO3, 17g NaHCO3 Tuy nhin x l s liu vi phn mm stagraphic thy trng lng to ti thu c nui trong iu kin mi trng c cha 16g NaHCO3 , 16,8g NaHCO3, 17g NaHCO3 l c s khc bit v phng din thng k hc (P < 0,05). Tc l s pht trin ca to trong iu kin mi trng c cha lng mui NaHCO3 khc nhau (16g NaHCO3 , 16,8g NaHCO3, 17g NaHCO3) l khc nhau. 20 17 17 16g 20 13 17 17 13 17 10 20 20 Nng mui NaHCO3 16,8g 13 17 17 20 20 17 17 17 17 17g 20 17 27 17 17 13

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S hnh thnh thnh cc hai phn ct thnh nhng an to nh

Hnh 4. 9 : S hnh thnh cc th hoi bo mu vng ca Spirulina platensis Kt qu thu c ng ngha vi vic c th nui Spirulina platensis cc iu kin mi trng c cha t 16 17g NaHCO3. Theo l thuyt th Spirulina platensis c th sng c trong mi trng c cha t 1,2 16,8 g NaHCO3. Vy kt qu thc nghim kho st l tng i ph hp vi th nghim a ra.

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th 4. 3 : Biu so snh trng lng to ti thu c iu kin mi trng cha hm lng mui bicarbonat khc nhau (16g NaHCO3, 16,8g NaHCO3, 17g NaHCO3). Nhn xt : t biu trn nhn thy mi trng cha 17g NaHCO3 th trng lng to ti thu hoch c l nhiu nht v cht lng tng i n nh qua ba ln th nghim. Nh vy nui Spirulina platensis trong phng th nghim vi vic kim sot v n nh mt s yu t nhit phng 34 37oC, pH = 8 11, cng nh sng 3000 3500 lux, tc khuy sc 500 ml/pht th mi trng c th cha lng mui bicarconat t 16 17g NaHCO3 to vn sinh trng pht trin tt, sinh khi thu c cao. 4.1.2.4 Th nghim 4 : Th nghim nh gi nh hng ca cc mi trng nui cy khc nhau ln s tng sinh khi to Spirulina: kho st nh hng ca cc mi trng nui cy khc nhau ln s tng sinh khi to Spirulina, tin hnh cy to ging Spirulina platensis nng 30% vo 300 ml mi trng dinh dng khc nhaubao gm : mi trng 1 : mi trng c bn (Zarrouk), mi trng 2 : mi trng 1 ml r ng + 16,8 g NaHCO3, mi trng 3 : mi trng 1,5 ml r ng + 16,8 g NaHCO3. Th nghim c thc hin lp li ba ln,

47

mi nghim thc tin hnh nui trong 3 chai nc bin. Sau 7 ngy nui cy tin hnh thu hoch bng li lc v cn trng lng to ti (mi chai nc bin ly mt mu to ti).

Bng 4. 5 : Trng lng to ti thu c sau 7 ngy nui cy (S g to ti/1Lmi trng) th nghim 4 t TN Mi trng c bn (Zarrouk) t I t II t II Cc mi trng nui cy Mi trng 1 ml r ng + 16.8 g NaHCO3 Mi trng 1,5 ml r ng + 16.8 g NaHCO3 20 23 23 20 17 13 23 23 13 13 27 20 17 23 17 23 20 17 23 13 17 23 13 20 17 10 20

Kt qu thu c ng ngha vi vic to Spirulina platensis c th sinh trng v pht trin tt trong c 3 loi mi trng (mi trng c bn (Zarrouk), mi trng 1 ml r ng + 16,8 g NaHCO3, mi trng 1,5 ml r ng + 16,8 g NaHCO3). C s khc bit v phng din thng k hc (P < 0,05) trng lng to ti thu c nui trong iu kin cc mi trng khc nhau (mi trng c bn (Zarrouk), mi trng 1 ml r ng + 16,8 g NaHCO3, mi trng 1,5 ml r ng + 16,8 g NaHCO3) khi x l s liu vi phn mm stagraphic. Tc l s pht trin sinh khi ca to trong cc mi trng khc nhau l khc nhau.

48

Hnh 4. 10 : Hnh thi si to trong mi trng c s dng r ng 1ml quan st x400

49

S hnh thnh cc bt kh khng tan trong chai to do sinh khi pht trin nhiu

Hnh 4. 11 : Kh nng ln sinh khi cao v c ca to trong mi trng 1ml r ng + 16,8g NaHCO3 Ngi ta nghin cu v tm ra rt nhiu cc mi trng nhn to n gin d kim m vn y dng cht cho s pht trin ca to Spirulina platensis, v mi trng r ng cng c th l mt trong nhng mi trng c th thay th mi trng c bn.Vy kt qu thc nghim kho st l tng i ph hp vi th nghim a ra.

50

th 4. 4 : Biu so snh trng lng to ti thu c iu kin mi trng khc nhau ( mi trng c bn (Zarrouk), mi trng 1 ml r ng + 16,8 g NaHCO3, mi trng 1,5 ml r ng + 16,8 g NaHCO3). Nhn xt : t biu trn nhn thy mi trng cha 1ml r ng + 16,8g NaHCO3 th trng lng to ti thu hoch c l nhiu nht v cht lng tng i n nh qua ba ln th nghim. Nh vy nui Spirulina platensis trong phng th nghim vi vic kim sot v n nh mt s yu t nhit phng 34 37oC, pH = 8 11, cng nh sng 3000 3500 lux, tc khuy sc 500 ml/pht th c th dng mi trng 1 ml r ng + 16,8 g NaHCO3 thay th cho mi trng c bn ( Zarrouk) m to vn sinh trng pht trin tt, sinh khi thu c cao. 4.2 Phng php thu hoch to Trong qu trnh lm th nghim nhn thy Spirulina l mt trong nhng i tng d dng thu hoch bng cc li lc vi ng knh l thch hp. C th ni li lc l cng c thu hoch to va tin li va d kim, m chi ph li khng cao qu. Vic thu hoch to tt, hiu qu cao th sinh khi thu c l mt iu ht sc n gin cho cc cng on ch bin to sau ny. Trn th gii, ngi ta thu hoch to theo nhiu phng php khc nhau.

51 Phng php ly tm vi vic s dng cht lng ng

Theo Glueke v Oswald (1965) nghin cu nh hng ca phn, cacbonmetylxenluloz bentonid v vi n hiu qu thu hi to bng phng php ly tm, h rt ra kt lun l khi cho cc cht ph gia vo dung dch v a pH ti 6,8 th vic thu hi to bng vic ly tm kh tt. Nhng gi thnh khi thu hoch to c th s dng ph gia kh cao, chng t phng php ny khng kinh t. Phng php kt t v tuyn ni

Nhiu nh khoa hc s dng thnh cng phng php kt t v tuyn ni thu hoch to. Theo phng php ny u tin ngi ta cho phn (l cht kt t) kt t to li sau sc khng kh vo cc cm kt ta ni ln v ngi ta vt ra ngoi. Tuy nhin theo phng php ny phi tiu tn kh nhiu ho cht (liu lng phn ti 70 100 mmg/1 lt dung dch), do hm lng phn cao nh vy trong sn phm c th gy c hi i vi cc ng vt nui. Phng php t kt ta

T kt ta l hin tng lng ng to sau mt thi gian nui cy do pH tng ln rt cao. V to tiu th CO2 nn pH tng ln dn dn ti vic kt ta ca hydroxyt magie (Mg(OH)2) v carbonatcanxi (CaCO3) s ko theo to lng xung. Vic thu hoch to theo phng php ny c mt s nhc im : do thu hoch bng lng trng lc dn ti yu cu phi tuyt i tnh, nhit v thi tit c th nh hng ti vic tng cao pH do nh hng ti vic lng ng to, mt khc theo phng php ny cn mt din tch kh rng. Phng php kt hp nh tc dng ca trng lc v lc ly tm

Nm 1967 cong ty SOSA (Mhic) a ra mt phng php thu hoch to kh kinh t : Dch to u tin c lc trn cc tm nghing nh tc dng ca trng lc. Sau dch to c lc tinh trn my lc trng quay hoc ly tm. Theo phng php ny khng phi tiu tn ho cht, sn phm to thu c m bo v sinh, sch s, thit b thu hoch kh n gin. (Nguyn Anh Dng, 1982).

52

Hnh 4. 12: To Spirulina Platensis thu hoch bng li lc Nh vy theo kt qu thc nghim th nghim v thng k cc phng php a ra, th vn thu hoch to bng li lc l ph hp vi cc th nghim dung tch nh trong iu kin phng th nghim. Li lc vi ng knh l lc ph hp m bo c cc thng s nh m bo v sinh, an ton, hiu qu, khng gy c hi, thit b n gin t tn km kinh t. 4.3 My khuy dung tch nh 4.3.1 Nguyn tc cu to Thit b khuy gm cc b phn c bn sau : Thng khuy hay cn gi l thng cha (6) hnh tr vi y trn, c lm t thng nc th tch ti a c th cha l 21L, bn trong l mi trng dch lng nui to cha y cc cht dinh dng cn thit. Theo ng tm ca thng lp trc khuy (8) vi cnh khuy (3). Trc khuy xuyn qua np v h phn trn bi mt trong hai chic trong cp bnh rng (4).Truyn chuyn ng cho trc khuy t ng c (5) qua nm iu chnh tc (2) to tc thch hp cho cnh khuy. Bin np (1) c nhim v n nh khi dng in chy qua ti v lm quay ng c. Khung s (7) c tc dng nng

53

v im ta cho ton b thit b khuy, bn trn c y np bng ba cactong cng gim s nh hng ca iu kin bn ngoi ti mi trng nui. Thit b khuy dung tch nh ny c ch to theo dng h, tc l khng c s ngn cch gia mi trng nui to vi mi trng bn ngoi.

Hnh 4. 13 : Nguyn tc cu to my khuy 4.3.2 Nguyn l hot ng Khi c dng in xoay chiu chy qua bin p chuyn i thnh dng mt chiu lm quay ng c. ng c truyn chuyn ng v lm quay trc khuy thng qua truyn chuyn ng cho cp bnh rng. Cnh khuy c gn mt cch chc chn trc khuy, v vy khi trc khuy quay ko theo s quay ca cnh khuy to chuyn ng trn trong dung dch nui ca thng cha. Nh vy trong mi trng nui to s hnh thnh mt khi dch lng chuyn ng thng nht, cht dinh dng s gp tip xc vi to cc v tr khc nhau, khng lm lng ng to, to s sinh trng v pht trin tt.

54 S hnh thnh cc vng to khi nui bng sc kh bnh nha 10L

Hnh 4. 14: Nui to trong cc bnh nha th tch 10L

Hnh 4. 15: M hnh 3D my khuy dung tch nh

55

4.3.3 ng dng nui to th tch nh Vi th tch cha trong bnh cha r 20 50 L, my khuy to ny c th p dng nui Spirulina platensis trong phng th nghim. Nu thng cha l thng nha dung tch ti a khong 20 L, t c hai thng trong khung ca my khuy vi mt khong cch thch hp nh hnh 4.15, mi thng s c khuy vi cc cnh khuy ring. Nh vy, trong mi thng dung dch to s l mt hn hp chuyn ng ng nht di tc dng ca thit b khuy, trnh c hin tng phn tng to trong dch nui cy. Khi thu hoch sinh khi to c th nng phn gi h thng ca thit b khuy, hai thng mi trng nui to s c ko ra d dng, thun tin cho vic b sung mi trng cng nh cung cp ging hay thu hoch to. Ngoi ra ta c th thay h thng hai thng cha bng mt t knh cha bng knh dung tch t 20 50L, khi s hnh thnh hai lung chuyn ng ca dch to trong t knh, to s c iu kin tip xc vi cht dinh dng sinh trng v pht trin n nh.

Thng ng dch to Spirulina platensis lng (mi trng Zarrouk)

Thng ng dch to Spirulina platensis lng (mi trng r ng)

B phn nng thit b khuy

Hnh 4. 16: My khuy ng dng nui to Spirulina platensis

56

PHN V : KT LUN V NGH5.1 Kt lun Qua qu trnh kho st bng thc nghim mt s phng php tng sinh khi to Spirulina platensis qui m phng th nghim chng ti rt ra mt s kt lun sau : 5.1.1 Th nghim tng sinh khi Spirulina platensis Vi cc khong nng nui cy ban u th s gia tng sinh khi to t l thun vi nng nui cy. C th nng cy to ging ban u l 20%, 25%, 30% th 30% trng lng to ti thu hoch c nhiu nht, v to c mu xanh m hn so vi nng 20%, 25%. Nh vy c s nh hng ca nng to ging ban u ti kh nng thu hoch to ti. nh sng nh hng n s gia tng sinh khi to. Vi cc nghim thc 1500 1750 lux, 3000 - 3500 lux, 4500 5250 lux khng nh to Spirulina platensis c th sng v sinh trng tt, trong iu kin cng nh sng t 1500 5250 lux. Trong khong cng t 3000 3500 lux to sinh trng v pht trin mnh v tt nht. Hm lng mui bicarbonat trong mi trng nui cy c nh hng ti kh nng tng sinh khi to. To Spirulina platensis c th sng v tn ti, pht trin mnh trong iu kin mi trng dinh dng c cha hm lng NaHCO3 t 16 17g. iu kin mi trng cha 17g NaHCO3, th trng lng to ti thu c nhiu nht v cht lng tng i n nh qua ba ln lp li th nghim. Mi trng khc nhau c nh hng ti vic tng sinh khi to (mt trng Zarrouk, mt trng 1 ml r ng + 16,8 g NaHCO3, mi trng 1,5 ml r ng + 16,8g NaCHO3). Spirulina platensis c th tng sinh v pht trin tt trong c ba loi mi trng trn. Mi trng 1 ml r ng + 16,8 g NaHCO3 v mi trng 1,5 ml r ng + 16,8g NaCHO3 c th thay th c mi trng c bn Zarrouk m hm lng sinh khi to vn cao. Trong mi trng 1 ml r ng + 16,8 g NaHCO3 trng lng to ti thu hoch c l nhiu v tng i n nh hn so vi hai mi trng cn li.

57

5.1.2 Phng php thu hoch to Theo thng k v thu thp th c rt nhiu phng php khc nhau thu hoch to Spirulina platensis. Trong qu trnh thc hin ti, chng ti thy phng php thu hoch bng li lc l tt nht v ng knh li lc ph hp th phng php ny vn cho kh nng thu hoch cao, hiu qu, an ton, v sinh, khng c hi v nhim mi trng. Bng kho st thc nghim trong cc th nghim tng sinh khi to thy nn dng li lc thu hoch Spirulina platensis. 5.1.3 My khuy to dung tch nh C th thit k cc my khuy to dung tch nh t 20 50L qui m phng th nghim vn c kh nng tng sinh khi to tt. Spirulina platensis c th khuy trong mi trng dch lng trong iu kin kho st th nghim cho kt qu sinh trng n nh sinh khi nhiu. My khuy to l mt trong nhng ng dng cho vic nui to th tch 20 50L, ngoi ra cn hn ch c vic ni vng to ca cc qu trnh sc kh khi nui to cc bnh nha th tch t 5 20L. 5.2. ngh Trong qu trnh thu hoch to cn tm cch kh mi tanh ca to, x l cc ho cht ca mi trng nui. Th nghim cc phng php gy nui tng sinh khi to quy m sn xut. B tr th nghim cc iu kin nhit thp v cao hn (ngoi khong nhit 34 37oC). Kho st thm tc ng cng gp ca cc yu t l ha trong khi nui cy Spirulina platensis phng th nghim. Nn tin hnh x l dch nui (sau khi thu hoch to) trnh lm nhim mi trng v cc h sinh thi. B tr th nghim thu hoch to vi nhiu c li lc vic thu hoch t kt qu ti u. Cht lng to sau khi thu hoch cn c kim nh v v sinh an ton thc phm. Cn th nghim nui to vi iu kin khuy trn b mt.

58

TI LIU THAM KHOTING VIT 1. William S. Gunther (2001) : Aphoto- Bioreactor With On- Line Biomass and Growth Rate Estimations for Optimization of Light Intensity in Cultures of Phototrophic Microorganisms. Masters Thesis Department of Life Science Aalbog University Sohngaardsholmsvej 49 DK- 9000 Aalbog. 2. V B Minh (2004) : K thut phn ng. Qu trnh v thit b cng ngh ho hc & thc phm trng i Hc Quc gia TP.HCM. 3. Ree Chou (1993) : Aquafeeds and feedinh strateries in Singapore. Ti liu mng 4. Qiang Hu and Milton Sommerfeld (2004) : Selection of hight performance microalgae for bioremediation of nitrate- contaminated groundwater. School of Life Sicences Arizona State University Tempe, AZ 85287- 4501. 5. Phm inh Thanh Nhn, Hong Thanh Phng (2005) : Tc ng ca cht kch thch sinh sn ln s gia tng s lng lun trng ( Brachionus plicatilis). Lun vn tt nghip trng i Hc Nng Lm TP.HCM. 6. Phm Hong H (1972) : To hc. Trung tm hc liu B gio dc. 7. O. Pulz ( 2001) : Photobiorectors : production systm for phototrophic microoganism. IGV Institute for Cereal Processing, Arthur- Scheunert- Alee 40/41, 14558 Bergholz- Rehbrucke, Germany. 8. Nguyn Vn La (1999) : Cc qu trnh v thit b c hc quyn I : Khuy Lng lc. Cc qu trnh v thit b trong cng nghip ho cht v thc phm trng i Hc K Thut TP.HCM. 9. Nguyn Thanh Tng (1998) : Ti nguyn v sinh thi rong. T sch trng i Hc Khoa Hc T Nhin i Hc Quc gia TP.HCM. 10. Nguyn c Lng (2002) : Vi sinh vt hc cng nghip. Cng ngh vi sinh tp II trng i Hc Bch Khoa i Hc Quc gia TP.HCM.

59

11. Nguyn Anh Dng, (1982) : Nghin cu, thit k c s sn xut to Spirulina t ngun nc khong Vnh Ho- Thun Hi. n tt nghip trng i Hc Bch Khoa H Ni. 12. ng nh Kim, ng Hong Phc Hin (1999) : Cng ngh sinh hc vi to. Trung tm khoa hc t nhin v Cng ngh Quc gia. 13. Malcolm R. Brown (2002) : Nutritional values and Use of Microalgae in Aquaculture. CISRO Marine Researh, GPO Box 1538, Hobart, 7001 Australia. 14. L Thanh Hng (2000) : Dinh dng v thc n thu sn. Bi ging trng i Hc Nng Lm TP.HCM. 15. L Th Phng Hng (1996) : Gp phn tm hiu s tng trng ca to lam Spirulina platensis (Nordst.) Geitler.. Lun vn thc s khoa hc khoa hc chuyn nghnh vi sinh trng i Hc Khoa Hc T Nhin i Hc Quc gia TP.HCM. 16. L nh Lng (1999) : Spirulina nui trng s dng trong y dc & dinh dng. Sch chuyn kho phc v Cng ngh sinh hc Y t Nh xut bn Y hc chi nhnh TP.HCM. 17. Eirik O. Duer, Augustin Molnar, and Vernon Sato (1998) : Cultured microalgae as aquaculture feeds. The Oceanic Institute, Makapuu Point, Waimanalo, HI 96795, USA. 18. Ed- Hanun Chang and Shang- Shyng Yang (2002) : Some characteristics microalgae isolated in Taiwan for biofixation of carbon dioxide. Department of Agricultural Chemistry, National Taiwan University, Tapei, Taiwan 1067. 19. Dng Tin c (1996) : Phn loi vi khun lam Vit Nam. Nh xut bn Nng nghip. 20. Bi Minh Tr (2005) : Vi to trong cng ngh sinh hc. Bi ging Cng ngh sinh hc thc vt trng i Hc Nng Lm TP.HCM. 21. Nguyn Vn Tuyn (2003) : a dng to trong thu vc ni a Vit Nam trin vng v th thch. Nh xut bn nng nghip.

60

PH LCPh lc 1 : Mi trng Zarrouk nui to ( ng nh Kim, ng Hong Phc Hin, 1999). Thnh Phn NaCl MgSO4.7H2O CaCl2 FeSO4.7H2O EDTA KH2PO4 NaNO3 K2SO4 NaHCO3 n v ( g/L) 1 0,2 0,04 0,01 0,08 0,5 2,5 1 16,8

STT 1 2 3 4 5 6 7 8 9

Ph lc 2 : Trng lng to ti thu c trong th nghim 1 (g/L) t Tn t I t II t III 10 7 13 Nng nui cy to ging Spirulina platensis ban u 20% 13 10 10 10 10 7 13 13 10 25% 13 13 17 17 17 10 17 17 17 30% 13 17 17 17 17 20

61

Ph lc 3 : Trng lng to ti thu c trong th nghim 3 (g/L) t Tn t I t II t III Ph lc 4 : Trng lng to ti thu c trong th nghim 3 (g/L) t Tn t I t II t III Ph lc 5 : Trng lng to ti thu c trong th nghim 4 (g/L) t Tn t I t II t III Cc loi mi trng khc nhau (ml/L) 0 ml r ng ( Zarrouk) 20 23 23 20 17 13 23 23 13 13 27 20 1 ml r ng + 16,8g NaHCO3 17 23 17 23 20 17 1,5 ml r ng +16,8g NaHCO3 23 13 17 23 13 20 17 10 20 20 17 17 Cc hm lng mui bicarbonat trong mi trng nui cy ( g/L) 16g NaHCO3 20 13 17 17 13 17 10 20 20 16g NaHCO3 13 17 17 20 20 17 16g NaHCO3 17 27 17 20 17 27 17 27 13 Cc cng chiu sng khc nhau 1500 1750 lux 17 17 20 17 17 20 20 13 13 3000 3500 lux 20 23 20 17 23 20 20 20 20 4500 5250 lux 23 17 17 27 17 23 20 10 23

62

Ph lc 6 : Bng Anova ca th nghim 1One-Way Analysis of Variance -------------------------------------------------------------------------------Data: NONGDO1.tro_ng_l__

Level codes: NONGDO1.no_ng__o__

Labels:

Means plot: LSD

Confidence level: 95

Range test: LSD

Analysis of variance -------------------------------------------------------------------------------Source of variation Sum of Squares d.f. Mean square F-ratio Sig. level

-------------------------------------------------------------------------------Between groups Within groups 213.85185 122.88889 2 24 106.92593 5.12037 20.882 .0000

-------------------------------------------------------------------------------Total (corrected) 336.74074 26

0 missing value(s) have been excluded.

Ph lc 7 : Bng trung bnh ca th nghim 1Table of means for NONGDO1.tro_ng_l__ by NONGDO1.no_ng__o__ -------------------------------------------------------------------------------Stnd. Error Stnd. Error Level Count 95 % LSD intervals for mean

Average (internal) (pooled s)

-------------------------------------------------------------------------------0.2 0.25 0.3 9 9 9 10.000000 13.666667 16.888889 .7071068 .9279607 .5879447 .7542745 .7542745 .7542745 8.898952 12.565619 15.787841 11.101048 14.767715 17.989937

-------------------------------------------------------------------------------Total 27 13.518519 .4354806 .4354806 12.882828 14.154209

63

Ph lc 8 : Trc nghim chi tit ca th nghim 1Multiple range analysis for NONGDO1.tro_ng_l__ by NONGDO1.no_ng__o__ -------------------------------------------------------------------------------Method: 95 Percent LSD Level Count Average Homogeneous Groups

-------------------------------------------------------------------------------0.2 0.25 0.3 9 9 9 10.000000 X 13.666667 16.888889 X X

-------------------------------------------------------------------------------contrast 0.2 - 0.25 0.2 - 0.3 0.25 - 0.3 difference -3.66667 -6.88889 -3.22222 limits 2.20210 * 2.20210 * 2.20210 *

-------------------------------------------------------------------------------* denotes a statistically significant difference.

Ph lc 9 : Bng Anova ca th nghim 2One-Way Analysis of Variance -------------------------------------------------------------------------------Data: ANHSAN1.Tro_ng_l__

Level codes: ANHSAN1.as

Labels:

Means plot: LSD

Confidence level: 95

Range test: LSD

Analysis of variance -------------------------------------------------------------------------------Source of variation Sum of Squares d.f. Mean square F-ratio Sig. level

-------------------------------------------------------------------------------Between groups Within groups 280.07407 58.88889 18 8 15.559671 7.361111 2.114 .1407

-------------------------------------------------------------------------------Total (corrected) 338.96296 26

64

0 missing value(s) have been excluded.

Ph lc 10 : Bng trung bnh ca th nghim 2Table of means for ANHSAN1.Tro_ng_l__ by ANHSAN1.as -------------------------------------------------------------------------------Stnd. Error Stnd. Error Level Count 95 % LSD intervals for mean

Average (internal) (pooled s)

-------------------------------------------------------------------------------1500 1 3000 3 3001 3 3002 3 3003 3 3004 3 3005 3 3006 3 3007 3 3008 3 4500 5 4501 5 4502 5 4503 5 4504 5 4505 5 4506 5 4507 5 4508 5 9 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 17.111111 20.000000 17.000000 20.000000 23.000000 23.000000 20.000000 20.000000 20.000000 20.000000 23.000000 27.000000 20.000000 17.000000 17.000000 10.000000 17.000000 23.000000 23.000000 .9043789 .0000000 .0000000 .0000000 .0000000 .0000000 .0000000 .0000000 .0000000 .0000000 .0000000 .0000000 .0000000 .0000000 .0000000 .0000000 .0000000 .0000000 .0000000 .9043789 2.7131368 2.7131368 2.7131368 2.7131368 2.7131368 2.7131368 2.7131368 2.7131368 2.7131368 2.7131368 2.7131368 2.7131368 2.7131368 2.7131368 2.7131368 2.7131368 2.7131368 2.7131368 15.636026 15.574745 12.574745 15.574745 18.574745 18.574745 15.574745 15.574745 15.574745 15.574745 18.574745 22.574745 15.574745 12.574745 12.574745 5.574745 12.574745 18.574745 18.574745 18.586196 24.425255 21.425255 24.425255 27.425255 27.425255 24.425255 24.425255 24.425255 24.425255 27.425255 31.425255 24.425255 21.425255 21.425255 14.425255 21.425255 27.425255 27.425255

-------------------------------------------------------------------------------Total 27 19.037037 .5221434 .5221434 18.185396 19.888678

Ph lc 11 : Trc nghim chi tit ca th nghim 2Multiple range analysis for ANHSAN1.Tro_ng_l__ by ANHSAN1.as -------------------------------------------------------------------------------Method: 95 Percent LSD

65Level Count Average Homogeneous Groups

-------------------------------------------------------------------------------4505 5 3001 3 4503 5 4504 5 4506 5 1500 1 3000 3 3002 3 3005 3 3006 3 3007 3 3008 3 4502 5 3003 3 3004 3 4500 5 4507 5 4508 5 4501 5 1 1 1 1 1 9 1 1 1 1 1 1 1 1 1 1 1 1 1 10.000000 X 17.000000 XX 17.000000 XX 17.000000 XX 17.000000 XX 17.111111 X 20.000000 XX 20.000000 XX 20.000000 XX 20.000000 XX 20.000000 XX 20.000000 XX 20.000000 XX 23.000000 XX 23.000000 XX 23.000000 XX 23.000000 XX 23.000000 XX 27.000000 X

-------------------------------------------------------------------------------contrast difference +/- limits -2.88889 0.11111 -2.88889 -5.88889 -5.88889 -2.88889 -2.88889 -2.88889 -2.88889 -5.88889 -9.88889 -2.88889 0.11111 0.11111 7.11111 6.59678 6.59678 6.59678 6.59678 6.59678 6.59678 6.59678 6.59678 6.59678 6.59678 6.59678 * 6.59678 6.59678 6.59678 6.59678 * 1500 1750 lux - 3000 3500 l 1500 1750 lux - 3001 3500 l 1500 1750 lux - 3002 3500 l 1500 1750 lux - 3003 3500 l 1500 1750 lux - 3004 3500 l 1500 1750 lux - 3005 3500 l 1500 1750 lux - 3006 3500 l 1500 1750 lux - 3007 3500 l 1500 1750 lux - 3008 3500 l 1500 1750 lux - 4500 5250 lu 1500 1750 lux - 4501 5250 lu 1500 1750 lux - 4502 5250 lu 1500 1750 lux - 4503 5250 lu 1500 1750 lux - 4504 5250 lu 1500 1750 lux - 4505 5250 lu

661500 1750 lux - 4506 5250 lu 1500 1750 lux - 4507 5250 lu 1500 1750 lux - 4508 5250 lu 3000 3500 lux - 3001 3500 l 3000 3500 lux - 3002 3500 l 3000 3500 lux - 3003 3500 l 3000 3500 lux - 3004 3500 l 3000 3500 lux - 3005 3500 l 3000 3500 lux - 3006 3500 l 3000 3500 lux - 3007 3500 l 3000 3500 lux - 3008 3500 l 3000 3500 lux - 4500 5250 lu 3000 3500 lux - 4501 5250 lu 3000 3500 lux - 4502 5250 lu 3000 3500 lux - 4503 5250 lu 3000 3500 lux - 4504 5250 lu 3000 3500 lux - 4505 5250 lu 3000 3500 lux - 4506 5250 lu 3000 3500 lux - 4507 5250 lu 3000 3500 lux - 4508 5250 lu 3001 3500 lux - 3002 3500 l 3001 3500 lux - 3003 3500 l 3001 3500 lux - 3004 3500 l 3001 3500 lux - 3005 3500 l 3001 3500 lux - 3006 3500 l 3001 3500 lux - 3007 3500 l 3001 3500 lux - 3008 3500 l 3001 3500 lux - 4500 5250 lu 3001 3500 lux - 4501 5250 lu 3001 3500 lux - 4502 5250 lu 3001 3500 lux - 4503 5250 lu 3001 3500 lux - 4504 5250 lu 3001 3500 lux - 4505 5250 lu 3001 3500 lux - 4506 5250 lu 3001 3500 lux - 4507 5250 lu 3001 3500 lux - 4508 5250 lu 3002 3500 lux - 3003 3500 l 3002 3500 lux - 3004 3500 l 0.11111 -5.88889 -5.88889 3.00000 0.00000 -3.00000 -3.00000 0.00000 0.00000 0.00000 0.00000 -3.00000 -7.00000 0.00000 3.00000 3.00000 10.0000 3.00000 -3.00000 -3.00000 -3.00000 -6.00000 -6.00000 -3.00000 -3.00000 -3.00000 -3.00000 -6.00000 -10.0000 -3.00000 0.00000 0.00000 7.00000 0.00000 -6.00000 -6.00000 -3.00000 -3.00000 6.59678 6.59678 6.59678 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 * 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 * 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051

673002 3500 lux - 3005 3500 l 3002 3500 lux - 3006 3500 l 3002 3500 lux - 3007 3500 l 3002 3500 lux - 3008 3500 l 3002 3500 lux - 4500 5250 lu 3002 3500 lux - 4501 5250 lu 3002 3500 lux - 4502 5250 lu 3002 3500 lux - 4503 5250 lu 3002 3500 lux - 4504 5250 lu 3002 3500 lux - 4505 5250 lu 3002 3500 lux - 4506 5250 lu 3002 3500 lux - 4507 5250 lu 3002 3500 lux - 4508 5250 lu 3003 3500 lux - 3004 3500 l 3003 3500 lux - 3005 3500 l 3003 3500 lux - 3006 3500 l 3003 3500 lux - 3007 3500 l 3003 3500 lux - 3008 3500 l 3003 3500 lux - 4500 5250 lu 3003 3500 lux - 4501 5250 lu 3003 3500 lux - 4502 5250 lu 3003 3500 lux - 4503 5250 lu 3003 3500 lux - 4504 5250 lu 3003 3500 lux - 4505 5250 lu 3003 3500 lux - 4506 5250 lu 3003 3500 lux - 4507 5250 lu 3003 3500 lux - 4508 5250 lu 3004 3500 lux - 3005 3500 l 3004 3500 lux - 3006 3500 l 3004 3500 lux - 3007 3500 l 3004 3500 lux - 3008 3500 l 3004 3500 lux - 4500 5250 lu 3004 3500 lux - 4501 5250 lu 3004 3500 lux - 4502 5250 lu 3004 3500 lux - 4503 5250 lu 3004 3500 lux - 4504 5250 lu 3004 3500 lux - 4505 5250 lu 3004 3500 lux - 4506 5250 lu 0.00000 0.00000 0.00000 0.00000 -3.00000 -7.00000 0.00000 3.00000 3.00000 10.0000 3.00000 -3.00000 -3.00000 0.00000 3.00000 3.00000 3.00000 3.00000 0.00000 -4.00000 3.00000 6.00000 6.00000 13.0000 6.00000 0.00000 0.00000 3.00000 3.00000 3.00000 3.00000 0.00000 -4.00000 3.00000 6.00000 6.00000 13.0000 6.00000 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 * 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 * 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 * 8.85051

683004 3500 lux - 4507 5250 lu 3004 3500 lux - 4508 5250 lu 3005 3500 lux - 3006 3500 l 3005 3500 lux - 3007 3500 l 3005 3500 lux - 3008 3500 l 3005 3500 lux - 4500 5250 lu 3005 3500 lux - 4501 5250 lu 3005 3500 lux - 4502 5250 lu 3005 3500 lux - 4503 5250 lu 3005 3500 lux - 4504 5250 lu 3005 3500 lux - 4505 5250 lu 3005 3500 lux - 4506 5250 lu 3005 3500 lux - 4507 5250 lu 3005 3500 lux - 4508 5250 lu 3006 3500 lux - 3007 3500 l 3006 3500 lux - 3008 3500 l 3006 3500 lux - 4500 5250 lu 3006 3500 lux - 4501 5250 lu 3006 3500 lux - 4502 5250 lu 3006 3500 lux - 4503 5250 lu 3006 3500 lux - 4504 5250 lu 3006 3500 lux - 4505 5250 lu 3006 3500 lux - 4506 5250 lu 3006 3500 lux - 4507 5250 lu 3006 3500 lux - 4508 5250 lu 3007 3500 lux - 3008 3500 l 3007 3500 lux - 4500 5250 lu 3007 3500 lux - 4501 5250 lu 3007 3500 lux - 4502 5250 lu 3007 3500 lux - 4503 5250 lu 3007 3500 lux - 4504 5250 lu 3007 3500 lux - 4505 5250 lu 3007 3500 lux - 4506 5250 lu 3007 3500 lux - 4507 5250 lu 3007 3500 lux - 4508 5250 lu 3008 3500 lux - 4500 5250 lu 3008 3500 lux - 4501 5250 lu 3008 3500 lux - 4502 5250 lu 0.00000 0.00000 0.00000 0.00000 0.00000 -3.00000 -7.00000 0.00000 3.00000 3.00000 10.0000 3.00000 -3.00000 -3.00000 0.00000 0.00000 -3.00000 -7.00000 0.00000 3.00000 3.00000 10.0000 3.00000 -3.00000 -3.00000 0.00000 -3.00000 -7.00000 0.00000 3.00000 3.00000 10.0000 3.00000 -3.00000 -3.00000 -3.00000 -7.00000 0.00000 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 * 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 * 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 * 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051

693008 3500 lux - 4503 5250 lu 3008 3500 lux - 4504 5250 lu 3008 3500 lux - 4505 5250 lu 3008 3500 lux - 4506 5250 lu 3008 3500 lux - 4507 5250 lu 3008 3500 lux - 4508 5250 lu 4500 5250 lux - 4501 5250 lu 4500 5250 lux - 4502 5250 lu 4500 5250 lux - 4503 5250 lu 4500 5250 lux - 4504 5250 lu 4500 5250 lux - 4505 5250 lu 4500 5250 lux - 4506 5250 lu 4500 5250 lux - 4507 5250 lu 4500 5250 lux - 4508 5250 lu 4501 5250 lux - 4502 5250 lu 4501 5250 lux - 4503 5250 lu 4501 5250 lux - 4504 5250 lu 4501 5250 lux - 4505 5250 lu 4501 5250 lux - 4506 5250 lu 4501 5250 lux - 4507 5250 lu 4501 5250 lux - 4508 5250 lu 4502 5250 lux - 4503 5250 lu 4502 5250 lux - 4504 5250 lu 4502 5250 lux - 4505 5250 lu 4502 5250 lux - 4506 5250 lu 4502 5250 lux - 4507 5250 lu 4502 5250 lux - 4508 5250 lu 4503 5250 lux - 4504 5250 lu 4503 5250 lux - 4505 5250 lu 4503 5250 lux - 4506 5250 lu 4503 5250 lux - 4507 5250 lu 4503 5250 lux - 4508 5250 lu 4504 5250 lux - 4505 5250 lu 4504 5250 lux - 4506 5250 lu 4504 5250 lux - 4507 5250 lu 4504 5250 lux - 4508 5250 lu 4505 5250 lux - 4506 5250 lu 4505 5250 lux - 4507 5250 lu 3.00000 3.00000 10.0000 3.00000 -3.00000 -3.00000 -4.00000 3.00000 6.00000 6.00000 13.0000 6.00000 0.00000 0.00000 7.00000 10.0000 10.0000 17.0000 10.0000 4.00000 4.00000 3.00000 3.00000 10.0000 3.00000 -3.00000 -3.00000 0.00000 7.00000 0.00000 -6.00000 -6.00000 7.00000 0.00000 -6.00000 -6.00000 -7.00000 -13.0000 8.85051 8.85051 8.85051 * 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 * 8.85051 8.85051 8.85051 8.85051 8.85051 * 8.85051 * 8.85051 * 8.85051 * 8.85051 8.85051 8.85051 8.85051 8.85051 * 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 8.85051 *

704505 5250 lux - 4508 5250 lu 4506 5250 lux - 4507 5250 lu 4506 5250 lux - 4508 5250 lu 4507 5250 lux - 4508 5250 lu -13.0000 -6.00000 -6.00000 0.00000 8.85051 * 8.85051 8.85051 8.85051

------------------------------------------------------------------------------- denotes a statistically significant difference.

Ph lc 12 : Bng Anova ca th nghim 3One-Way Analysis of Variance -------------------------------------------------------------------------------Data: KHOILU1.Tro_ng_l__

Level codes: KHOILU1.kho_i_l__2

Labels:

Means plot: LSD

Confidence level: 95

Range test: LSD

Analysis of variance -------------------------------------------------------------------------------Source of variation Sum of Squares d.f. Mean square F-ratio Sig. level

-------------------------------------------------------------------------------Between groups Within groups 446.96296 .00000 22 4 111.74074 .00000 999.999 .0000

-------------------------------------------------------------------------------Total (corrected) 446.96296 26

0 missing value(s) have been excluded.

Ph lc 13 : Bng trung bnh ca th nghim 3Table of means for KHOILU1.Tro_ng_l__ by KHOILU1.kho_i_l__1 -------------------------------------------------------------------------------Stnd. Error Stnd. Error Level Count 95 % LSD intervals for mean

Average (internal) (pooled s)

71-------------------------------------------------------------------------------16 g 16,8 g 17 g 9 9 9 16.777778 17.111111 20.222222 .8296214 1.1837375 1.7933347 1.3298566 1.3298566 1.3298566 14.836527 15.169860 18.280972 18.719028 19.052362 22.163473

-------------------------------------------------------------------------------Total 27 18.037037 .7677931 .7677931 16.916255 19.157819

Ph lc 14 : Trc nghim chi tit ca th nghim 3Multiple range analysis for KHOILU1.Tro_ng_l__ by KHOILU1.kho_i_l__1 -------------------------------------------------------------------------------Method: 95 Percent LSD Level Count Average Homogeneous Groups

-------------------------------------------------------------------------------16 g 16,8 g 17 g 9 9 9 16.777778 X 17.111111 X 20.222222 X

-------------------------------------------------------------------------------contrast 16 g - 16,8 g 16 g - 17 g 16,8 g - 17 g difference -0.33333 -3.44444 -3.11111 limits 3.88250 3.88250 3.88250

-------------------------------------------------------------------------------* denotes a statistically significant difference.

Ph lc 15 : Bng Anova ca th nghim 4One-Way Analysis of Variance -------------------------------------------------------------------------------Data: MOITRU1.Tro_ng_l__

Level codes: MOITRU1.Kho_i_l__1

Labels:

Means plot: LSD

Confidence level: 95

Range test: LSD

72

Analysis of variance -------------------------------------------------------------------------------Source of variation Sum of Squares d.f. Mean square F-ratio Sig. level

-------------------------------------------------------------------------------Between groups Within groups 29.85185 452.22222 2 24 14.925926 18.842593 .792 .4644

-------------------------------------------------------------------------------Total (corrected) 482.07407 26

0 missing value(s) have been excluded.

Ph lc 16 : Bng trung bnh ca th nghim 4Table of means for MOITRU1.Tro_ng_l__ by MOITRU1.Kho_i_l__1 -------------------------------------------------------------------------------Stnd. Error Stnd. Error Level Count 95 % LSD intervals for mean

Average (internal) (pooled s)

-------------------------------------------------------------------------------0 ml 1 ml 1,5 ml 9 9 9 19.444444 19.666667 17.333333 1.3955396 1.4043583 1.5365907 1.4469352 1.4469352 1.4469352 17.332289 17.554511 15.221178 21.556600 21.778822 19.445489

-------------------------------------------------------------------------------Total 27 18.814815 .8353884 .8353884 17.595361 20.034268

Ph lc 17 : Trc nghim chi tit ca th nghim 4Multiple range analysis for MOITRU1.Tro_ng_l__ by MOITRU1.Kho_i_l__1 -------------------------------------------------------------------------------Method: 95 Percent LSD Level Count Average Homogeneous Groups

-------------------------------------------------------------------------------1,5 ml 0 ml 1 ml 9 9 9 17.333333 X 19.444444 X 19.666667 X

--------------------------------------------------------------------------------

73contrast 0 ml - 1 ml 0 ml - 1,5 ml 1 ml - 1,5 ml difference -0.22222 2.11111 2.33333 limits 4.22431 4.22431 4.22431

------------------------------------------------------------------------------- denotes a statistically significant difference.

Ph lc 18 : Bn v nguyn tc cu to ca my khuy

74

Ph lc 19 : M hnh 3D ca my khuy

LI CM NThnh knh gi li cm n n : * Ban gim hiu trng i hc Nng Lm thnh ph H Ch Minh, Ban ch nhim b mn Cng ngh Sinh hc, cng tt c qu Thy C truyn t kin thc qu bu cho em trong sut qu trnh hc tp ti trng. * C L Th Phng Hng tn tnh hng dn, gip v to mi iu kin cho em thc hin v hon tt kha lun tt nghip ny. * C Phm Th Hng Hnh, c V Th Thanh Bnh, c ng Th Thanh Ha, c Trn Hng Thy khoa Thy Sn to mi iu kin gip em trong sut qu trnh thc hin ti ti phng th nghim 305. * Cc bn lp Cng ngh Sinh hc 28 ng vin, gip ti khi kh khn cng nh chia x nhng nim vui ni bun trong sut thi gian hc tp. * Bn H Tn lp Nui trng Thu sn 28, bn Tun Anh lp C kh 28A gip ti trong sut thi gian thc hin ti. * Cui cng con xin gi li cm n su sc chn thnh nht ti s c v v ng vin ca gia nh, b m v em ang v s mi l im ta, ch da vng chc c v tinh thn ln vt cht, cho con nim tin v ng lc vo chnh bn thn vn ln.

iii

TM TTng dng ca Spirulina platensis trong thc tin y sinh hc ln i sng ca con ngi ngy cng c m rng nhiu hn. Cc nghin cu nhm tng sinh khi v kho nghim nh hng ca cc iu kin khc nhau ln to ny c ch v quan tm c bit. Vn t ra l lm sao tng sinh khi Spirulina trong qu trnh nui cy iu kin phng th nghim nhm p ng tt cc ng dng quan trng trn. Xut pht t chng ti tin hnh cc nghin cu nhm tng sinh khi Spirulina platensis. Th nghim 1 : nh gi nh hng ca nng nui cy ban u ln kh nng thu hoch to. Th nghim 2 : nh gi nh hng ca ch chiu sng ln s tng sinh khi to. Th nghim 3 : nh gi nh hng ca khi lng mui bicarbonat trong mi trng nui cy ln s tng sinh khi to Spirulina. Th nghim 4 : nh gi nh hng ca cc mi trng nui cy khc nhau ln s tng sinh khi to Spirulina. Qu trnh thc hin cc nghin cu trn kt hp vi vic a ra phng php thu hoch to thch hp, xut v th nghim m hnh my khuy to dung tch nh p dng cho nui Spirulina platensis qui m phng th nghim. Kt qu thu c sau khi x l s liu chng ti nhn thy nng sut to Spirulina platensis tng theo s tng ca nng nui cy ban u trong khong nng cy t 20% - 30%. S nh hng ca cng chiu sng ti tng sinh khi ca to l c c s, cng nh sng thch hp nht nui to Spirulina platensis trong iu kin phng th nghim l 3000 3500 lux, tuy nhin to vn c kh nng tng trng v pht trin tt trong iu kin chiu sng t 1500 5250 lux. Khi lng mui bicarbonat (NaHCO3) c nh hng ti mi trng nui to, Spirulina platensis c th sng c vi hm lng mui NaHCO3 t 16 - 17g/L mi trng nui. Mi trng r ng c th thay th c mi trng c bn (Zarrouk) trong nui to Spirulina platensis, nn pha mi trng 1ml r ng + 16,8g NaHCO3 tng sinh to Spirulina. Phng php thch hp nht trong cc th nghim thu hoch to Spirulina l dng li lc. My khuy to dung tch nh c th c dng nui Spirulina platensis vi th tch cha t 20 50L nui trong iu kin phng th nghim

iv

MC LCLI CM Niii TM TT..iv MC LC..v,vi,vii DANH SCH CC BNG...viii DANH SCH CC HNH V THix,x

PHN I : M U...1 1.1 t vn .................................................................................................................... 3 1.2 Mc ch nghin cu ................................................................................................... 3 1.3 Yu cu ........................................................................................................................ 4 PHN II : TNG QUAN TI LIU........3 2.1 To Spirulina platensis ................................................................................................ 5 2.1.1 Lch s pht trin v cc cng trnh gy nui to Spirulina trong v ngoi nc 5 2.2.1 Phn loi ................................................................................................................ 9 2.2.2 Phn b .................................................................................................................. 9 2.2.3. Hnh thi v cu to............................................................................................ 10 2.2.4. c im dinh dng ca Spirulina platensis ................................................... 10 2.2.5. c im sinh sn ca Spirulina platensis......................................................... 13 2.3 iu kin nui cy v cc yu t nh hng n qu trnh nui to Spirulina platensis ........................................................................................................................... 14 2.3.1 nh hng ca nh sng ..................................................................................... 14 2.3.2 Nhit ............................................................................................................... 15 2.3.3 Thng s pH .................................................................................................. 15 2.4 Thnh phn ho hc ca Spirulina platensis ............................................................. 15 2.5 Vai tr, v tr ca to Spirulina trong cng ngh sinh hc (CNSH)....................... 18 2.6 Mt r (hay r ng) .............................................................................................. 21v

2.7 Cc kiu thit b ln men c th ng dng trong nui to ......................................... 23 2.7.1 Thit b c cnh khuy ........................................................................................ 23 2.7.2 Thit b c h thng thi kh ............................................................................... 26 PHN III : VT LIU V PHNG PHP24 3.1 a im v thi gian