Volume 3 • Issue 5 • 1000147J Anal Bioanal TechniquesISSN:2155-9872 JABT, an open access journal

Open AccessResearch Article

Paranthaman et al., J Anal Bioanal Techniques 2012, 3:5 DOI: 10.4172/2155-9872.1000147

Keywords: Amaranthus caudatus; RP-HPLC; Flavonoids; Pytochem-icals; GC-MS

IntroductionThe genus Amaranthus belongs to the family Amaranthaceae

and includes more than 60 species, of which three viz., Amaranthus hypochondriacus, A. cruentus and A. caudatus, are the essential grain species. Amaranth is a very versatile crop that is grown in a wide range of agro-climatic conditions; it resists drought, heat, and pests, and adapts readily to new environments, including some that are inhospitable to conventional cereal crops [1,2]. It is one of the few multi-purpose crops, which can supply grains and tasty leafy vegetables of high nutritional quality as a food and animal feed, and additionally an ornamental plant, because of an attractive inflorescence colouration [3,4]. The biomass of amaranth, both as green and dried, has high biological value, and is used as source of protein, amino acid and dietary fibre for fattened pigs, rabbits, and lambs [5,6]. Another article concerning the phenolic and flavonoid content in amaranth (Amaranthus hypochondriacus) has also recently been published [7]. Pasko et al. [8] analysed the total polyphenol content and anti-oxidant activity in two amaranth varieties (Amaranthus cruentus). Gallic acid (GA), Caffeic acid (CA), Rutin (RU), Ferulic acid (FA) and Quercetin (QU) are phenolic compounds. Structurally they have phenolic groups which serve as a source of readily available hydrogen atoms such that the subsequent radicals produced can be delocalized over the phenolic structure (Figure 1) [9,10]. Great focus has been put on health promoting secondarymetabolites in food during the recent decade. A number of studieshave been conducted on the health effects of polyphenols (flavonoidsand phenolic acids). Flavonoids have been shown to inhibit certaintypes of cancer, dementia, cardiovascular diseases and diabetes [11-14]. Ultraviolet detection (UV) [15] reversed phase high-performanceliquid chromatography with ultraviolet detection (HPLC-UV) [16,17]have been used for analysis of flavonoids. The purpose of this study wasto identify and quantify health promoting flavonoids in Amaranthuscaudatus leaves. In Tamil Nadu state of India amaranth is consumedregularly as favourite dish where it is steamed and mashed with lightseasoning salt, red chilies and cumin.

In this study, HPLC with UV detector was developed for simultaneous determination of Gallic acid (GA), Caffeic acid (CA),

Rutin (RU), Ferulic acid (FA) and Quercetin (QU) in the leaf extracts of Amaranth caudatus.

Materials and MethodsRP-HPLC Analysis of flavonoids

Standard preparation: Standard stock solutions of five phenolic like Gallic acid (GA), Caffeic acid (CA), rutin (RU), Ferulic acid

*Corresponding author: R. Paranthaman, Technical Assistant, Indian Institute of Crop Processing Technology, Ministry of Food Processing Industries, Govt. of India, Thanjavur-613 005 (TamilNadu), India, Tel: 04362226676; E-mail: paranthhu@gmail.com

Received July 10, 2012; Accepted September 21, 2012; Published September 27, 2012

Citation: Paranthaman R, Praveen kumar P, Kumaravel S (2012) GC-MS Analysis of Phytochemicals and Simultaneous Determination of Flavonoids in Amaranthus caudatus (Sirukeerai) by RP-HPLC. J Anal Bioanal Techniques 3:147. doi:10.4172/2155-9872.1000147

Copyright: © 2012 Paranthaman R, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

AbstractA sensitive and selective high performance liquid chromatography method (HPLC) for simultaneous analysis of

following five flavonoids like Gallic acid (GA), Caffeic acid (CA), Rutin (RU), Ferulic acid (FA) and Quercetin (QU) in Amaranthus caudatus (Sirukeerai) leaves. The results demonstrated that the Amaranthus caudatus leaves were separately extracted and analyzed using RP HPLC method. The contents of Gallic acid (0.083 μg/gm), Caffeic acid (0.004 μg/gm), Rutin (0.019 μg/gm), Quercetin (0.001 μg/gm) and Ferulic acid (0.001 μg/gm) in Amaranthus caudatus leaves. The GC-MS study also carried out and it showed the presence of phytochemicals. Hence these plants extracts with the property of bioavailability and retention of certain minerals by polyphenolic compounds can be recommended for their use as an alternative anti-infective agent in natural medicine for the treatment of infectious diseases.

GC-MS Analysis of Phytochemicals and Simultaneous Determination of Flavonoids in Amaranthus caudatus (Sirukeerai) by RP-HPLCParanthaman R1*, Praveen kumar P2, and Kumaravel S3

1Technical Assistant, Indian Institute of Crop Processing Technology, Ministry of Food Processing Industries, Govt. of India, Thanjavur, India2Senior Research Fellow, Indian Institute of Crop Processing Technology, Ministry of Food Processing Industries, Govt. of India, Thanjavur, India3Scientist & Head i/c, Indian Institute of Crop Processing Technology, Ministry of Food Processing Industries, Govt. of India, Thanjavur, India

0 5 10 15 20 25 30 35 40

3.5

3.0

2.5

2.0

1.5

1.0

0.5

0.0

3.5

3.0

2.5

2.0

1.5

1.0

0.5

0.0

Minutes

Detector A (280nm)Mixed flavonoids standard 6. 8.10 10ulFLAVONOIDS NIXED 11.dat

Retention TimeNameArea

5.75

0 G

allic

aci

d 56

7448

02

9.45

0 C

affe

ic a

cid

174

4347

110

.517

Rut

in 4

2056

735

12.4

00 Q

uerc

etin

133

9646

7

24.1

75 F

erul

ic a

cid

281

0655

Figure 1: HPLC Chromatogram of flavonoids standards.

Journal ofAnalytical & Bioanalytical TechniquesJo

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ical & Bioanalytical Techniques

ISSN: 2155-9872

Volume 3 • Issue 5 • 1000147J Anal Bioanal TechniquesISSN:2155-9872 JABT, an open access journal

Citation: Paranthaman R, Praveen kumar P, Kumaravel S (2012) GC-MS Analysis of Phytochemicals and Simultaneous Determination of Flavonoids in Amaranthus caudatus (Sirukeerai) by RP-HPLC. J Anal Bioanal Techniques 3:147. doi:10.4172/2155-9872.1000147

Page 2 of 4

(FA) and Quercetin (QU) compounds were prepared in methanol, at concentrations of 2, 4, 6, 8 and 10 μg/ml, all standard solutions were filtered through HPLC filter 0.45 mm membrane filter (Millipore).

Sample preparation: The sample was prepared according to the procedure. The extraction was carried out using 2 ml of fermented broth with 50 mL of 95% ethanol under 80 KHz, 45°C in ultrasonic extraction device for 30 min, repeated twice. The extract was collected and filtered; the filtrate was dried at 50°C under reduced pressure in a rotary evaporator. The dried crude extract was dissolved in the 100 ml mobile phase. After filtering through a filter paper and a 0.45 mm membrane filter (Millipore), the extract was injected into HPLC.

HPLC conditions: Flavonoids were analysed using a RP-HPLC method [18], Shimadzu Corp., Kyoto, consisting of a LC-10ATVp pump, SCL 10A system controller and a variable Shimadzu SPD-10ATVp UV VIS detector and a loop injector with a loop size of 20 μl. The peak area was calculated with a CLASSVP software. Reverse-phase chromatographic analysis was carried out in isocratic conditions using a C-18 reverse phase column (250×4.6 mm i.d., particle size 5 μm, Luna 5μ C-18; phenomenex, Torrance, CA, USA) at 25°C. The gradient elution of solvent A [water-acetic acid (25:1 v/v)] and solvent B (methanol) had a significant effect on the resolution of compounds. As a result, solvent gradients were formed, using dual pumping system, by varying the proportion of solvent A [water-acetic acid (25:1, v/v)] to solvent B (methanol). Solvent B was increased to 50% in 4 min and subsequently increased to 80% in 10 min at a flow rate of 1.0 mL/min. Detection wavelength was 280 nm. Gallic acid (GA), caffeic acid (CA), rutin (RU), Ferulic acid (FA) and quercetin (QU) was used as internal and external standards. Phenolic acids present in each sample were identified by comparing chromatographic peaks with the retention time (Rt) of individual standards and further confirmed by co-injection with isolated standards. The amount of each phenolic acid is expressed as micrograms per gram of fresh weight unless otherwise stated.

Phytochemical analysis by GC-MS

Preparation of extract: Leaves of Amaranthus caudatus (Sirukeerai) were shade dried. 20 g of the powdered leaves were soaked in 95% ethanol for 12 h. The extracts were then filtered through Whatmann filter paper No. 41 along with 2 gm sodium sulfate to remove the sediments and traces of water in the filtrate. Before filtering, the filter paper along with sodium sulphate was wetted with 95% ethanol. The filtrate was then concentrated by bubbling nitrogen gas into the solution. The extract contained both polar and non-polar phytocomponents of the plant material used. 2 μl of these solutions was employed for GC/MS analysis [19].

Results and Discussion

SPD10Avp (280nm)Pk # Reten-

tion Time

Area Height Area Percent

Height Per-cent

concen-tration

Units Name

1. 5.750 56744802 2757981 42.84 29.72 10.000 μg/ml Gallic acid2. 9.450 17443471 1882880 13.17 20.29 10.000 μg/ml Caffeic

acid3. 10.517 42056735 3198304 31.75 34.47 10.000 μg/ml Rutin4. 12.400 13396467 1402866 10.11 15.12 10.000 μg/ml Quercetin5. 24.175 2810655 36358 2.12 0.39 10.000 μg/ml Ferulic

acid

Table 1: HPLC Validation data for flavonoids standards.

5.55

8 G

allic

aci

d 4

7353

8

Retention TimeNameArea

Detector A (280nm)commercial 796 10ul 19.4 11acommercial 796 10ul 19.4 11a

9.49

2 C

affe

ic a

cid

60.

0410

.450

Rut

in 8

2086

12.3

33 Q

uerc

etin

286

13.2

25

917

4

23.2

58

200

24.5

00 F

erul

ic a

cid

56

0.08

0.06

0.04

0.02

0.00

-0.02

-0.04

0.08

0.06

0.04

0.02

0.00

-0.02

-0.04

Minutes4 6 8 10 12 14 16 18 20 22 24

Figure 2: HPLC Chromatogram of Amaranth caudatus leaves.

SPD10Avp (280nm)Pk # Retention

TimeArea Height Area

PercentHeight Percent

con-centra-tion

Units Name

1. 5.558 473538 44270 82.61 90.74 0.083 μg/gm Gallic acid2. 9.492 6924 678 1.21 1.39 0.004 μg/gm Caffeic

acid3. 10.450 82086 3646 14.34 7.46 0.019 μg/gm Rutin4. 12.333 286 70 0.05 0.14 0.001 μg/gm Quercetin5. 24.500 56 2 0.01 0.00 0.001 μg/gm Ferulic

acid

Table 2: HPLC Validation data for Amaranth caudatus leaves.

Phenolic compounds can be defined as a large series of chemical constituents possessing at least one aromatic ring, bearing hydroxyl and other sub-constituents. RP-HPLC analysis is the most used method for the identification of plant phenolic compounds. Because of the diversity and complexity of natural phenolics in medicinal plants, it is difficult to characterize every compound and elucidate its structure. However; it is not difficult to identify the major categories of phenolic compounds. The chromatographic separations of Retention time (Rt), Gallic acid (Rt-5.750), Caffeic acid (Rt-9.450), Rutin (Rt-10.517), Quercetin (Rt-12.400) and Ferulic acid (Rt-24.175) standard shown in Figure 1. The content of each flavonoid was calculated from the corresponding calibration curve and presented as the mean of five determinations as shown in Table 1. The HPLC Result shows based on the Retention time (Rt), Gallic acid (Rt-5.558), Caffeic acid (Rt-9.492), Rutin (Rt-10.450), Quercetin (Rt-12.333) and Ferulic acid (Rt-24.50) content in Amaranthus caudatus leaves was found to be 0.083 μg/gm, 0.004 μg/gm, 0.019 μg/gm, 0.001 μg/gm, and 0.001 μg/gm. The obtained value was compared with standard (figure 2).

GC analysis: GC-MS analysis was carried out on a GC CLARUS 500 PerkinElmer system comprising a gas chromatograph interfaced to a mass spectrometer (GC-MS) instrument employing the following conditions: column Elite-1 fused silica capillary column (30×0.25 mm ID×1EM df, composed of 100% Dimethyl poly siloxane), operating in electron impact mode at 70 eV; helium (99.999%) was used as carrier gas at a constant flow of 1ml/min and an injection volume of 0.5 EI was employed (split ratio of 10:1) injector temperature 250°C; ion-source temperature 280°C. The oven temperature was programmed from 110°C (isothermal for 2 min), with an increase of 10°C/min, to 200°C, then 5°C/min to 280°C, ending with a 9 min isothermal at 280°C. Mass spectra were taken at 70 eV; a scan interval of 0.5 s and fragments from 40 to 550 Da [20].

Volume 3 • Issue 5 • 1000147J Anal Bioanal TechniquesISSN:2155-9872 JABT, an open access journal

Citation: Paranthaman R, Praveen kumar P, Kumaravel S (2012) GC-MS Analysis of Phytochemicals and Simultaneous Determination of Flavonoids in Amaranthus caudatus (Sirukeerai) by RP-HPLC. J Anal Bioanal Techniques 3:147. doi:10.4172/2155-9872.1000147

Page 3 of 4

in Table 3. The GC-MS chromatogram with peak area was given in fig-ure 3. The activity of important phyto-components identified in Ama-ranth caudatus leaf extract shown in table 4 and figure 4.

GC-MS analysis Free radicals play a crucial role in the development of tissue damage

in pathological events. The extraction method presented is simple, rapid and inexpensive, with reduced solvent consumption. GC-MS method used for the analysis of the obtained extracts can be an interesting tool for testing the amount of some active principles in herbs used in cosmetic, drugs, pharmaceutical or food industry. The acidic fractions were silylated and subjected to GC-MS investigation. It is evident from the table 2 that all fractions have a complex chemical composition. Some of the GC-MS peaks remained unidentified, because of lack of authentic samples and library data of corresponding compounds.

All the twelve compounds have been identified for the first time in Amaranth caudatus. The ethanol extract of the plant showed 12 con-stituents, the major constituents were Isoxazolidine, 5-hexyl-(+)-(peak area 0.47%), 1,2,4-Butanetriol (peak area 0.47%), trinitrate, N-Ethyl-N’-nitroguanidine (peak area 0.47%), Phenol, 2,6-bis(1,1-dimethylethyl)-4-methyl, methylcarbamate (peak area 2.37%), 2,5-Pyrrolidinedione, 3-ethyl-1, 3-dimethyl-(peak area 0.16%), 2-Piperidinone, N-[4-bro-mo-n-butyl]-(peak area 0.16%), 3-Hexadecyloxycarbonyl-5-(2-hydroxyethyl)-4-methylimidazolium ion (peak area 0.16%), 2-(3-Oxo-3-phenylpropyl)-3,5,6-trimethylpyrazine (peak area 0.47%), Pyridine-3-carboxamide, 4-dimethylamino-N-(2,4-difluorophenyl)-(peak area 1.11%), Phytol (peak area 84.97%), Pseudoephedrine, (+)-(peak area 2.06%), Aspidofractinine-3-methanol (peak area 7.12%) were reported

No. RT Name of the compound Molecular MW Peak Area %

1. 4.61 Isoxazolidine, 5-hexyl-, (+)- C9H19NO 157 0.472. 4.79 1,2,4-Butanetriol, trinitrate C4H7N3O9 241 0.473. 4.91 N-Ethyl-N’-nitroguanidine C3H8N4O2 132 0.474. 7.94 Phenol, 2,6-bis(1,1-dimethylethyl)-4-

methyl-, methylcarbamate C17H27NO2 277 2.37

5. 8.31 2,5-Pyrrolidinedione, 3-ethyl-1,3-dimethyl-

C8H13NO2 155 0.16

6. 8.93 2-Piperidinone, N-[4-bromo-n-butyl]- C9H16BrNO 233 0.167. 11.16 3-Hexadecyloxycarbonyl-5-(2-

hydroxyethyl)-4-methylimidazolium ion C24H45N2O3 409 0.16

8. 11.97 2-(3-Oxo-3-phenylpropyl)-3,5,6-trimeth-ylpyrazine

C16H18N2O 254 0.47

9. 13.09 Pyridine-3-carboxamide, 4-dimethylami-no-N-(2,4-difluorophenyl)-

C14H13F-2N3O

277 1.11

10. 14.96 Phytol C20H40O 296 84.9711. 19.82 Pseudoephedrine, (+)- C10H15NO 165 2.06

RT=Retention time, MW=Molecular Weight, Table 3: Phytocomponents identified in the methanolic extract of the leaves of Amaranth caudatus by GC-MS.

Amaranthus caudatus (sirukeerrai) IICPT, Thanjavur, 22-JUL-2011 + 12:13:53GC-MS Analysis44 Scan EL+

TIC6.85e6100

02.75 3.75 4.75 5.75 6.75 7.75 8.75 9.75 10.75 11.75 12.75 13.75 14.75

%

2.62

2.71

2.90

2.97

3.18

7.94

8.31 8.939.2710.09 10.70

11.61 11.97

12.3313.46

13.09

14.2914.65

Time

Figure 3: GC-MS Chromatogram of Amaranth caudatus leaves.

Phenol

PyrolidionePhytol

100

50

0

100

50

0

100

50

0

57O

O

HN

HO

41

40 60 80 100 120 140 160 180 200 220 240 260

40 160 280 400 40 150 260 370

65

(mainlib) Phenol, 2,6-bis(1,1-dimethylethyl)-4-methyl-, methylcarbamate

(mainlib) 2,5-Pyrrolidinedione, 3-ethyl.(replib) Phytol

77

71 127

55O

ON

43

278

91 105145 161 177 189

220

205

Figure 4: GC-MS Spectrum of identified compounds

No. RT Name of the com-pound

Uses

4. 7.94 Phenol, 2,6-bis(1,1-dimethylethyl)-4-meth-yl-, methylcarbamate

Phenol is used as an oral anesthetic/analgesic, commonly used to temporarily treat pharyngitis. Phenol was widely used as an antiseptic, especially as Carbolic soap, from the early 1900s through the 1970s.

9. 13.09 Pyridine-3-carboxamide, 4-dimethylamino-N-(2,4-difluorophenyl)-

It has demonstrated anti-inflammatory actions that may be of benefit to patients with inflammatory skin conditions. It has ability to block the inflammatory actions of iodides known to precipitate or exacerbate inflammatory acne

10. 14.96 Phytol It can be used as a precursor for the manufacture of synthetic forms of vitamin E and vitamin K1. In ruminants, the gut fermentation of ingested plant materials liberates phytol, a constituent of chlorophyll, which is then converted to phytanic acid and stored in fats

11. 19.82 Pseudoephedrine, (+)- Pseudoephedrine shrinks swollen nasal mucous membranes. It reduces tissue hyperemia, edema, and nasal congestion commonly associated with colds or allergies. Other beneficial effects may include increasing the drainage of sinus secretions, and opening of obstructed Eustachian tubes. The same vasoconstriction action can also result in hypertension, which is a noted side effect of pseudoephedrine

Table 4: Activity of important phyto-components identified in Amaranth caudatus leaf extract by GC-MS.

Volume 3 • Issue 5 • 1000147J Anal Bioanal TechniquesISSN:2155-9872 JABT, an open access journal

Citation: Paranthaman R, Praveen kumar P, Kumaravel S (2012) GC-MS Analysis of Phytochemicals and Simultaneous Determination of Flavonoids in Amaranthus caudatus (Sirukeerai) by RP-HPLC. J Anal Bioanal Techniques 3:147. doi:10.4172/2155-9872.1000147

Page 4 of 4

Conclusion This HPLC procedure provided excellent identification and

quantification of these five flavonoids compounds presented in Amaranthus caudatus leaves. The HPLC results indicated that Amaranthus caudatus leaf extract contained an especially high concentration of gallic acid (0.083 μg/gm of dry weight). It was also shown that Caffeic acid, quercetin, rutin and ferulic acid were detected in Amaranthus caudatus leaves. Since these flavonoids have been of interest of health benefits, the present analytical study could be a potential application to identify and quantify the phenolic compounds in other medicinal plant extracts. In GC-MS results indicated twelve phytochemical constituents have been identified from ethanolic extract of the leaves of Amaranthus caudatus by Gas Chromatogram-Mass spectrometry (GC-MS) analysis. Phenolic compounds have also been known as antioxidant agents, which act as free radical terminators and have shown medicinal activity as well as exhibiting physiological functions. It was reported that compounds such as flavonoids, which contain hydroxyls, are responsible for the radical scavenging effects of most plants. The presence of these phytochemicals in Amaranthus caudatus root is a significant finding in this present study.

FundingThis work was supported by Indian Institute of crop processing

technology, Pudukottai road, Thanjavur, Tamilnadu.

Acknowledgment

The reaches deeply thanks the Dr. K. Alagusundaram, Director, Indian Institute of Crop Processing Technology, Ministry of Food Processing Industries, Government of India, Thanjavur for Providing all the facilities and support used to carry out the work.

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