tetras educare plus biochemistry lab manual edited

7/31/2019 TETRAS EDUCARE PLUS Biochemistry Lab Manual Edited

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EXP. NO: 1 DATE:

SAFEETY MEASURES IN BIOCHEMISTRY LAB

General Safety measure1. Lab can be dangerous places in to work all uses to be aware of the potential

hazards and to know what to do process of emergency when starting work in anew lab is important to become familiar with the layout of the room andlocation of the safety equipments.

2. The portion of the emergency exists, fire alarm and extension should beknown, so that the appropriate action can be taken in the current of fire.

3. The main labs for gas, water and switch for electricity should also be locatedso that the serious can be turned off for on emergency.

Safety measures:1. Lab workers must know the meaning of safety signs. Some of these are in

plain English while others are in the form of pictograms. The signs have beenstandardized in any terms, lettering, diagram and colours so that they can berapidly identified.

Personal protection:

1. Gloves: Heavy gloves must be used when handling corrosive substances suchas strong acids and Alkalies. The hazardous nature of there substances isobvious but the danger inherent in skin contact with other chemicals are notalways clear. Light weight disposable gloves must be used during weighingand handling of chemicals to avoid the risk of absorption through the skin.

2. Protective clothing: Lab coats are not status symbols but are meant toprotect from chemical and infection material. Cotton Is a better material fora lab coat and nylon has a greater absorbing capacity and is generally mostresistant to chemicals. The standard open neck coat may be appropriate formost chemical works. But high necked coats are more suitable for work withanimals and potentially dangerous microbes.

3. Face masks: These are not always necessary but need to be work. There is arisk of dust from chemicals or from aerosols of microbes.

Dangers to avoid:

Poisoning often arises from the accidental transfer of a compound through themouth and their misle can be greatly reduced by always keeping three simple rulesin the lab.

1. No smoking

2. No eating or drinking

3. No mouth pipetting

First aid

First aid, the name implies the help given immediately to on injured person.It is not a substitute for a medical or hospital attention. The following short notes


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are not a substitute for a proper course in first aid but should be of same help if youfind yourself dealing the subject of the lab accident.

Immediate assistance:

Artificial respiration:

a. The brain is unable to function for more than a few minutes, without oxygenand brain damage or death quickly follows.

b. If the casualty has stopped breathing artificial respiration must be started atonce.

c. It should be really applied by someone trained for this technique.

Unconscious:

a. If breathing has stopped, apply artificial respiration immediately.

b. If the victim is breathing their lay him face down with his head on one side

and his arms and legs on that side in a bent position.c. This position makes it easier for the patient and proudest better circulation of

blood to all part of the body.

Burns:

1. If the causality is on fire, immediately to down the flame, wrap hern in a fireblanket.

2. Then cool the affected area by running water.

3. When acid burns occur in the lab, the suitable alkali must be applied gentlywith a solution of sodium bi carbonate.

4. When electric burns occur in the lab, switch off the current or if it is notpossible free the person using anything non conductive.


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QUALITATIVE ANALYSIS OF CARBOHYDRATES

AIM:

To identify different carbohydrates in the given sample.

PRINCIPLE:

Qualitative test for carbohydrate classified into three category

(i)Those which are base reducing property aldehyde and keto group.

(ii)Those which are base are dehydration of hydroxyl group by strong acids andtreating the resultant furfural with various compounds to form colour compound.

(iii)Preparation of derivatives.

(i)Based on reducing properties:

Carbohydrate possessing a free or potentially free aldehyde or ketone groupsof the properties of readily reducing ion of certain metals such as copper ion

Bismuth, silver, mercury etc., Bismuth many test for sugar based on this properties.In the presence of reducing sugar the blue cupric hydroxide is reducing to insolubleyellow (or) red (or) green cuprous oxide. Large particles formed by slow reductionreaction and formed brick redwhereasvery small particles formed by fast reductionmay be formed greenish color. The amount of precipitate is not there color ofprimary consideration. Fehlings test, Benedicts test and Barfoeds test based onthis property. Benedicts is more stable than Fehlings. Barfoeds test is carried inthe slightly acidic state.

(ii)Test based on dehydration:

Stable in dilute acid but treat in strong acids resulting in the loss of water andthe formation of furfural (or) furfural derivatives.

CHO OHCH2 C-CHO

-3H2O

(CHOH) 4 C C

CH2OH O

(Furfural)

Hexose Aromatic compoundColored substances

CHO OHCH2 C-CHO

Conc. acid

(CHOH) 3 C C

O

CH2OH (Furfural)

Pentose Aromatic compound

Colored substances


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The furfural is a reactive compound and it reacts with a number of phenolicand other compounds to produce completecoloured products they are used for theidentification and determination.

Test which are based on the above reaction(i)Molischs test

(ii)Anthrone test

(iii)Bials test

(iv)Seliwanoffs test

PREPARATION OF REAGENTS

(i)Molischs reagent:

5gms of alpha napthol dissolved in 100ml of alcohol

(ii)Iodine solution:

5gms of potassium iodine and 1.2gms of iodine (or) grounted in mortor pestleand dissolved in water and made up to 500ml.

(iii)Fehlings reagent:

It is a mixture of copper sulphate and alkaline tartarate solution prepared asfollows.

Fehlings A:

36.65gms of copper sulphate is dissolved in water and made up in 500ml

Fehlings B:

125gms of potassium hydroxide 123gms of sodium potassium tartarate dissolved inwater and made up to 500ml. These two solutions are prepared separately in todifferent bottles whenever needed mix equal volume of solution A and solutionB.

(iv)Benedicts reagent:

85gms of sodium citrate 50gms of sodium carbonate are dissolved in about400ml of water by heating 17.3gms of copper sulphate is dissolved separately inabout 100ml of water carefully pour the copper solution in the carbonate solutionwith stirring finally the solution is made up to 1 litre.

(v)Barfoeds reagent:

13.5gms of crystalise copper acetate in 200ml of boiling water filtrate isnecessary and 1.8ml of glycial acetate.

(vi)Bials reagent:

1.5gms oforcinal is dissolved in 500ml of concentrated hydrochloric acid

containing 20-30 drops of ferric chloride solution.


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(vii)Seliwanoffs reagent:

50mgms ofresorcinol is dissolved in 100ml of 0.4N hydrochloric acid.

(viii)Tollens reagent:

A pinch of glucinol is dissolved in concentrated hydrochloric acid and used for

the test.

(ix)Phenylhydrazine reagent:

10gms of phenylhydrazine is added to 60ml of water and warmed it anddissolved 50gms sodium acetate is added to 10ml of glycol acetate and stored inbrown bottle.

(x)picric acid reagent:

0.2 _____ .2gms of picric acid dissolved in 100ml of distilledwater


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EXPT. NO. DATE:

GENERAL PROCEDURE OF CARBOHYDRATE

Sl.No EXPERIMENT OBSERVATION INFERENCE

1

2

3.

4

5

Solubility test:

A small amount of substance is taken in thetest tube and a fewdrops of water is added.

Molischs test:To 1ml of samplesolution, added 2 dropsof Molischs reagent andmixed well. To thismixture 2ml of conc.H2SO4 is added along theside of the test tube.

Iodine test:

To 1ml of solution add afew drops of iodinesolution.

Fehlings test:

To 1ml of test solutionadd a few drops

fehlings mixture andheat in a boiling waterbath.

Benedicts test:

To 3ml of sugar solutionand few drops of Benedicts reagent isadded and heated inboiling water bath for 3minutes then allowed to

cool.

1. Soluble.

2.Insoluble

A violet colour ringwas formed at thejunction of twoliquids.

1. Blue colour wasobtained.

2. Reddish browncolour was obtained.

A red colour solution(or) red precipitate

was obtained.

1. Green and thengreen precipitate isobtained.

2. No characteristicchange.

1.Presence of monosaccharide

(Or) disaccharides.

2. Presence of starch.

This indicates presenceof carbohydrate.

Presence of starch.

Presence of glycogen.

It indicates the

presence of reducingsugar. The redprecipitate is cuprousoxide.

1. Due to the reducingaction of sugar.

2. Presence of non

reducing sugars.


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6.

7.

8.

9.

10.

Picric acid test:

To 2 ml of test solutionadd 2 ml of picric acid.

Barfords test:

To 5ml of Barfordsreagent, add 5ml of testsolution and heat in aboiling water bath for 5minutes.

Seliwanoffs test:

To 5drops of testsolution, 3 ml of seliwanoffs reagent isadded and boiled forfew minutes in direct

flame.

Bials test:

To 2ml of Bials solutionand heat in directflame.

Phenyl hydrazine test:To 5ml of sugar solution,add on equal amount ofphenyl hydrazinehydrochloride andsodium acetate. Thenadd 1ml of glacial aceticacid and shake themixture well, Filter theabove solution, now the

filtrate is boiled in awater bath until yellow

A red coloredsolution is obtained.

1. A brick redprecipitate isobtained within 5minutes.


1. Cherry red colorsolution is obtained.


1. Green colorsolution is obtained.


1. A whiteprecipitate at roomtemperature, afterheating yellowprecipitate isformed.

2.Yellow color

Due to the formation ofpicramic acid. Itindicates the presenceof the reducing sugar.

It indicates presence ofmonosaccharide.

Presence of maltoseand sucrose. This showsDisaccharides.

It indicates thepresence of ketosugars.

Presence of aldosugars.

It is due to thepresence of pentose.

Presence of aldosesugar.

Presence of mannose.


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precipitate is formed.The precipitate isobserved under themicroscope to note thecrystals.

precipitate obtainedafter 5 minutes, thecrystals are viewunder microscope.

3. Yellow colorprecipitate obtainedafter 10-20 minutes,needle shapecrystals wereobserved under the

microscope.

4. Yellow colorprecipitate obtainedafter 30 minutes,flower shape crystalswere observed under

the microscope.

5. Yellow colorprecipitate obtainedafter 30 minutes,puff shape or cottonballshape crystals

were observed underthe microscope.

6. Yellow colorprecipitate obtained

2. Needle shapedcrystals called asructosome. It indicatespresence of fructose.

3. The needle shape ofcrystals is Glucozone.

This indicates presenceof glucose.

4. The flower shape of

crystals is glactazone.This indicates presenceof galactose.

5. The puff shape orcotton ball shape ofcrystals is lactazone.This indicates presenceof lactose.


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after 45 minutes,flower bud shapecrystals wereobserved under themicroscope.

7. Yellow colorprecipitate obtainedafter 20 minutes andwithin 30 minutes,sharp needle shape

crystals wereobserved under themicroscope.

6. The flower budshape of crystals ismaltazone. Thisindicates presence ofmaltose.

7. The sharp needleshape of crystals isxylazone. This indicatespresence of xylose.

HYDROLYSIS OF SUCROSE:

To 10ml of sugar solution, add 5-10 drops of hydrochloric acid and heat in aboiling water bath for 20 minutes and then cool it. Then neutralized with sodiumcarbonate. Then filter the solution, the filtrate used for the further studies.

HYDROLYSIS OF POLYSACCHARIDES:

1% of starch solution is taken in 100 ml of conical flask and add 5ml of

concentrated HCL. The resulting mixture is divided in to 5 equal parts into differenttest tubes and placed the test tubes in a boiling water bath. Remove the test tubesfrom boiling water bath at the interval of 1, 5,8,12 and 20 minutes. Divide thesolution of each test tubes in two parts. Then the solution is neutralized by sodiumcarbonate. One part of the test solution is performing with Benedicts test andsecond part is performed with Iodine test. This result, hydrolyzed starch isconformed.

RESULT:


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EXP.NO: DATE:

REACTIONS OF GLUCOSE

S.No EXPERIMENT OBSERVATION INFERENCE

1

2

3.

4

5

6.

7.

Solubility test:

A small amount of substance is taken in thetest tube and a few dropsof water is added.

Molischs test:

To 1ml of sample solution,added 2 drops of Molischs

reagent and mixed well.To this mixture 2ml ofconc H2SO4 is added alongthe side of the test tube.

Iodine test:


Fehlings test:

To 1ml of test solutionadd a few drops fehlingsmixture and heat in aboiling water bath.

Benedicts test:

To 3ml of sugar solutionand few drops of Benedicts reagent isadded and heated in

boiling water bath for 3minutes then allowed tocool.

Picric acid test:


Barfords test:

To 5ml of Barfordsreagent, add 5ml of test

solution and heat in aboiling water bath for 5

.

.


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8.

9.

10.

minutes.

Seliwanoffs test:

To 5drops of test solution,3 ml of seliwanoffsreagent is added andboiled for few minutes indirect flame.

Bials test:

To 2ml of Bials solutionand heat in direct flame.

Phenyl hydrazine test:

To 5ml of sugar solution,add on equal amount ofphenyl hydrazinehydrochloride and sodiumacetate. Then add 1ml ofglacial acetic acid andshake the mixture well,Filter the above solution,now the filtrate is boiledin a water bath untilyellow precipitate isformed. The precipitate is

observed under themicroscope to note thecrystals.

RESULT:

The given sugar sample is

1.

2.

3.

4.

EXP.NO: DATE:


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REACTIONS OF FRUCTOSE


1

2

3.

4

5

6.

7.

Solubility test:


Molischs test:

To 1ml of sample solution,added 2 drops of Molischsreagent and mixed well.

To this mixture 2ml ofconc H2SO4 is added alongthe side of the test tube.

Iodine test:


Fehlings test:

To 1ml of test solution

add a few drops fehlingsmixture and heat in aboiling water bath.

Benedicts test:


cool.

Picric acid test:


Barfords test:

To 5ml of Barfordsreagent, add 5ml of testsolution and heat in aboiling water bath for 5

minutes.

.

.


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8.

9.

10.

Seliwanoffs test:

To 5drops of test solution,3 ml of seliwanoffsreagent is added and

boiled for few minutes indirect flame.

Bials test:



To 5ml of sugar solution,add on equal amount ofphenyl hydrazine

hydrochloride and sodiumacetate. Then add 1ml ofglacial acetic acid andshake the mixture well,Filter the above solution,now the filtrate is boiledin a water bath untilyellow precipitate isformed. The precipitate isobserved under themicroscope to note thecrystals.

RESULT:


1.

2.

3.

4.

EXP.NO: DATE:


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REACTIONS OF LACTOSE


1

2

3.

4

5

6.

7.

Solubility test:


Molischs test:



Iodine test:


Fehlings test:

To 1ml of test solution

add a few drops fehlingsmixture and heat in aboiling water bath.

Benedicts test:


cool.

Picric acid test:


Barfords test:

To 5ml of Barfordsreagent, add 5ml of testsolution and heat in aboiling water bath for 5

minutes.

.

.


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8.

9.

10.

Seliwanoffs test:


Bials test:



To 5ml of sugar solution,add on equal amount ofphenyl hydrazinehydrochloride and sodiumacetate. Then add 1ml ofglacial acetic acid andshake the mixture well,Filter the above solution,now the filtrate is boiledin a water bath untilyellow precipitate is

formed. The precipitate isobserved under themicroscope to note thecrystals.

RESULT:


1.

2.

3.

4.


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EXP.NO: DATE:

REACTIONS OF MALTOSE


1

2

3.

4

5

6.

Solubility test:


Molischs test:To 1ml of sample solution,added 2 drops of Molischsreagent and mixed well.To this mixture 2ml ofconc H2SO4 is added alongthe side of the test tube.

Iodine test:


Fehlings test:


Benedicts test:

To 3ml of sugar solutionand few drops of Benedicts reagent isadded and heated inboiling water bath for 3minutes then allowed tocool.

Picric acid test:


Barfords test:

.

.


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7.

8.

9.

10.


Seliwanoffs test:


Bials test:

To 2ml of Bials solution

and heat in direct flame.Phenyl hydrazine test:

To 5ml of sugar solution,add on equal amount ofphenyl hydrazinehydrochloride and sodiumacetate. Then add 1ml ofglacial acetic acid andshake the mixture well,Filter the above solution,

now the filtrate is boiledin a water bath untilyellow precipitate isformed. The precipitate isobserved under themicroscope to note thecrystals.

RESULT:


1.

2.

3.

4.


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EXP.NO: DATE:

REACTIONS OF SUCROSE

AIM:

To determine the presence of sucrose in a given sample.

HYDROLYSIS OF SUCROSE:

To 10ml of sugar solution, add 5-10 drops of hydrochloric acid and heat in aboiling water bath for 20 minutes and then cool it. Then neutralized with sodiumcarbonate. Then filter the solution, the filtrate used for the further studies.


1.

2.

3.

4.

Solubility test:


Molischs test:



Benedicts test:

To 3ml of sugar solutionand few drops of Benedicts reagent isadded and heated inboiling water bath for 3minutes then allowed tocool.

Fehlings test:


Barfords test:

.


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5.

6.


Seliwanoffs test:


RESULT:The given sugar sample is

1.

2.

3.

4.


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EXP.NO: DATE:

REACTIONS OF POLYSACCHARIDES

AIM:

To determine the presence of polysaccharides in a given sample.

HYDROLYSIS OF POLYSACCHARIDES:

1% of starch solution is taken in 100 ml of conical flask and adds 5ml ofconcentrated HCL. The resulting mixture is divided in to 5 equal parts into differenttest tubes and placed the test tubes in a boiling water bath. Remove the test tubesfrom boiling water bath at the interval of 1, 5,8,12 and 20 minutes. Divide thesolution of each test tubes in two parts. Then the solution is neutralized by sodiumcarbonate. One part of the test solution is performing with Benedicts test andsecond part is performed with Iodine test. This result, hydrolyzed starch is

conformed.


1.

2.

3.

4.

Solubility test:

A small amount of substance is taken in thetest tube and a few dropsof water are added.

Iodine test:


Molischs test:

To 1ml of sample solution,

added 2 drops of Molischsreagent and mixed well.To this mixture 2ml ofconc H2SO4 is added alongthe side of the test tube.

Benedicts test:

To 3ml of sugar solutionand few drops of Benedicts reagent isadded and heated in

boiling water bath for 3minutes then allowed to

.


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5.

6.

7.

cool.

Fehlings test:


Barfords test:


Seliwanoffs test:


.

RESULT:


1.

2.

3.

4.


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ESTIMATION OF REDUCING SUGAR BY BENEDICTS

QUANTITATIVE REAGENT

AIM:

To estimate the amount of reducing sugar present in the given unknown sample by

Benedicts method.

PRINCIPLE:

Benedicts quantitative reagent is the modified form of qualitative reagent. It

consists of cupric sulphate, sodium carbonate and sodium citrate, potassium thiocyanate,

and potassium ferrocyanide. The alkali present in the Benedicts reagent enolises the sugar,

thereby causing them to be a strong reducing agent. Ferrocyanide serves to dissolve the

copper hydroxide while thiocyanate helps to convert the red cuprous oxide to whit crystals

of cuprous thiocyanate, which gives the clear end point.

REAGENTS REQUIRED

(i)Benedicts quantitative reagent (BQR)

(a)Cupric sulphate, (b) Sodium carbonate, (c) Sodium citrate, (d) Potassium

thiocyanate, (e) Potassium ferrocyanate.

(ii)Anhydrous sodium carbonate

(iii)Working standard glucose solution (100mg of glucose in 100 ml of distilled water)

(iv) Porcelain beads.

PROCEDURE:

Titration I: Standardisation of Benedicts Qualitative Reagent

Accurately pipette out 10 ml of Benedicts quantitative reagent into a clean conical flask.

One spatula full of 1 g of sodium carbonate was added into the conical flask. Few pieces of

porcelain beads were also added in order to avoid bumping. The contents were brought to

temperature approximately 60-700C. The contents were titrated against the standard

glucose solution with regular shaking until the blue colour disappeared. The end point is the

appearance of chalky white precipitate. The titrations were repeated for concordant values.

Titration II: Estimation of Glucose

The given unknown sample solution was made up to 100ml with distilled water in a standard

flask. It was shaken well for uniform concentration. The burette was filled with this

unknown solution and the titrations were performed as mentioned above till the appearance

of chalky white precipitate. The titrations were repeated for concordant values.


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Tabulation:

Titration I: Standardization of Benedicts Quantitative reagent

Std Glucose Vs Benedicts Quantitative reagent

Indicator: Self

S.No. Contents in conical Burette reading Concordant ValueFlask

(ml)

Initial Final (ml)

1.

2.

3.

Titration II: Estimation of GlucoseStandard Benedicts Quantitative reagent Vs Unknown Glucose

Indicator: Self

Unknown Glucose solution Vs Benedicts Quantitative reagent

Indicator: Self

S.No. Contents in conical Burette reading Concordant ValueFlask

(ml)

Initial Final (ml)

1.

2.

3.

Calculation

Standardization of glucose:

---- ml of standard glucose is needed for reducing 10 ml of Benedicts quantitative reagent.

But 100mg of glucose is present in 100 ml of solution. Hence 1 ml contains 1mg of glucose.

But X ml of standard glucose is used up for the reduction of 10 ml of Benedicts reagent, so X

ml of standard glucose solution corresponds to X mg of glucose.

But,

During estimation of glucose present in unknown solution, Y ml of unknown glucose is used

up for the reduction of 10 ml of Benedicts quantitative reagent.

Hence X mg of glucose is present in Y ml of unknown sugar sample.

Hence,

100 of the unknown glucose solution contains = X mg x 100 ml

Y ml


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Result:

The amount of glucose present in 100ml of the given solution =__________mg

ASSAY OF AMYLASE ACTIVITY

AIM: to assay the activity of the given salivary amylase enzyme sample.

Principle:


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In any enzyme assay the rate of the reaction can be known by measuring the amount

of substrate that is utilized or amount of product that is formed in unit time. Amylase is a

hydrolytic enzyme which breaks down starch (polysaccharides) into smaller units called as

maltose. However, they can be converted to a colored product by specific chemical

reactions. Here maltose reacts with alkaline dinitrosalicylic acid to give a reddish orange or

orange color. The amount of maltose thus produced in unit time can be measured by using

a colorimeter at 520nm, which gives an idea about the enzyme activity.

Reagents required:

1. 0.1N phosphate buffer (pH 6.7)

2. Dinitro salicylic acid reagent (DNS reagent) : it was prepared by dissolving 1 gram of

3.5 dinitro salicylic acid, 30 grams of sodium potassium tartarate and 1.6 grams ofsodium hydroxide in distilled water and made up to 100 ml with the same.

3. Starch solution : it acts as a substrate. 0.5% starch solution was prepared by

weighing 1 gram of soluble starch in 200 ml of phosphate buffer.

4. 1% sodium chloride solution : 1 gram of sodium chloride in 100 ml of distilled water.

5. Enzyme solution : Dilute 1 ml of saliva with distilled water and make up the volume

to 20 ml. This gives 1:20 dilution of enzyme.

6. Standard maltose solution (1mg/ml): 100 mg or 0.1 gram of maltose was weighed

and dissolved in distilled water and final volume was made up to 100 ml by using

standard volumetric flask.

7. 2N Sodium hydroxide solution : act as a denaturing agent for enzyme. It was

prepared by dissolving 8 grams of sodium hydroxide pellets in 100 ml of distilled

water.

Procedure:

A. Prepartion of standard graph for maltose: Pipette out different aliquots (0.2 to

1.0ml) of standard maltose solution and make up the volume to 2 ml by using

distilled water. To this solution 2 ml of DNS reagent was added. The cocktail or

mixtures in the test tubes were kept in boiling water bath for about 10 minutes. The

tubes were cooled and the mixture was diluted by addition of 10 ml of distilled

water. The resultant reddish orange or orange color was read at 520 nm by using a

digital colorimeter. The blank was prepared in just the same way but by addition of

distilled water instead of maltose solution. Prepare the standard graph by plotting

the concentration of maltose on x axis and the optical density values on y axis.

Tabular column 1:preparation of standard graphSl. Name of Vol. of std, Conc of Vol. of Vol. of Condition Vol. of OD at


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No. the test maltose

soln (ml)

standard

(g)

dist.

Water

(ml)

DNS

reagent

(ml)

distille

d

water

520nm

01 Blank 0.0 0000 2.0

2.0

Keepthetesttuvesinboiling

waterbathfor10minutes,cool

10 ml

02 Std 1 0.2 0200 1.803 Std 2 0.4 0400 1.604 Std 3 0.6 0600 1.405 Std 4 0.8 0800 1.206 Std 5 1.0 1000 1.0

B. Enzyme Assay:

For the enzyme assay 0.5 ml of 1: 20 diluted enzyme sample was taken. The

enzyme assay can be done by estimating the maltose produced by the enzyme. The

amylase enzymatic assay was performed as shown in tabular column 2.

Tabular column 2: Enzyme assay:

Sl. No. Substrates to beadded

Blank tube(ml)

Control tube(ml)

Test (ml)

01 Phosphate buffer 2.5 2.5 2.502 Starch solution 2.5 2.5 2.503 1% NaCl 1.0 1.0 1.004 Enzyme solution 0.0 0.5 0.505 2N NaOH 0.5 0.5 ---

Leave the tubes at 370C for 15 minutes06 2N NaOH --- --- 0.507 DNS reagent 2.0 2.0 2.0

Keep the tubes in boiling water bath for 10 mins, cool08 Distilled water 5.5 5.0 5.009 OD at 520 nm

Calculation:


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tetras educare plus biochemistry lab manual edited

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