Extraction of Nasunin from Different Colored Egg Plant Peels and its Phytochemical Screening by GC-MS

 

S. Anbuselvi, Sravanthi  Sistla M. A. Nikhil Kumar, Roshini Esther

Department of Industrial Biotechnology, BIHER, Chennai

*Corresponding Author E-mail: drsanbuselvi@gmail.com

 

ABSTRACT:

The present study was designed to extract nasunin and evaluated the effect of phytochemicals preset in different varieties of eggplants in Tamil Nadu, India. In vitro analysis of antioxidant activity of DPPH radical scavenging, reducing properties were analyzed in different varieties. The biochemical constituents of carbohydrates, proteins, lipids, dietary fibre and total phenol contents of both the ripe and unripe eggplant were also evaluated. The results indicate that purple color eggplant showed higher amount of nasunin antioxidants and phenolics than white colored varieties However, both purple and white colored varieties of eggplant exerted similar free radical scavenging activity and reducing property. We concluded that when consumed both varieties of green and purple coloured varieties of eggplant can be considered as potential bioactive compounds and antioxidant sources were identified by HPLC and GC-MS.

 

KEYWORDS: Nasunin, methanolic extract, Polyphenols, antioxidants.

 

 


INTRODUCTION:

Eggplant, a edible fruit is also called aubergine or brinjal (Solanum melongena L.), which is cultivated in Asia and Europe. Two kinds of anthocyanin have been isolated and identified from the purple eggplant. The role of anthocyanin pigments has medicinal agents and well-accepted dogma in medicine throughout the world[1-3].

 

Nasunin is highest amount of potent antioxidants. It helps to neutralize free radicals and inhibit generation of hydroxyl ions, making it an excellent antiaging phytonutrient[4-6]. It has antiangiogenic properties which help it to fight cancer by restricting the growth of new blood vessels. It also helps to maintain blood vessels clear and relaxed. Nasunin functions to scavenge excess iron in the body which prevent a free radical chain reaction that damages cells. In the way it is also protective of brain cells and other parts of the nervous system[7]. The most prominent natural source of nasunin is the skin of egg plants. It was isolated from the plant in 1993. This is only gives eggplant fruits the purplish -blue coloration. In eggplants it functions to protect the plant from environment damage, especially from the sun.[8,9].

 

The anthocyanin delphinidin-3-rutinoside was identified from eggplant by HPLC-DAD-MS3 analyses. A second anthocyanin, delphinidin-3-(p-coumaroylrutinoside)-5-glucoside (nasunin), was isolated as purple coloured crystals from eggplant peels. Properties of Nasunin: Delphinine, Delphinidin-3-(p-coumaroylrutinoside)-5-glucoside, Delphinidin-3-(4-p-coumaroylrhamnosyl(1-6) glucoside)-5-glucoside Hydrogen bond Acceptor count-23, Hydrogen bond Donor count-14, Hydrogen bond Donor count-13.[10,11].

 

Currently, nasunin is not found in any commercially available supplements. Nasunin supplementation will likely be available in the form of capsules in near future. The antiangiogenic property of nasunin means that it suppresses the development of new blood vessels. Since the average person does not need to develop new blood vessels this is more benefit than problem. This means that young and pregnant mothers should avoid consuming eggplants([12].

 

The nasunin is present in very few foods and eggplants are the natural source that contains significantly more. In particular, this phyto nutrient is more concentrated in the peels. The eggplant is then rich in soluble fiber (particularly of pectin) and also has interesting levels of potassium. Moreover, eggplant peel has a very low glycemic index (GI 15) and is therefore useful in the diet also to prevent and manage disorders such first overweight and diabetes[13]. The present study deals with the extraction of nasunin from different varieties of egg plants and its biochemical constituents were analyzed.

 

MATERIALS AND METHODS:

Different varieties of eggplants were collected from the market of different places in Tamil Nadu. The pulp and peel of different varieties were homogenized in 100 ml of distilled water, filtered using a Whatman filter paper and the filtrate were kept (at 0- 4°C) in a refrigerator and used for analysis within a maximum of seven days. The filtrate serves as the stock solution for all determinations.

 

Extraction Procedure of Nasunin:

100 g of purple and green varieties of eggplant peels cut into small pieces were soaked in 200 mL of 10% acetic acid for 24 hours under constant agitation. After recovery of the solvent, the peels were added 200 mL of glacial acetic acid and kept for an additional 24 h. After filtration, the peels were presented to colorless. The extracts were pooled for dryness to rotary evaporator at 40°C. The crude extract was treated first with 200 mL of methanol, brought to dryness and then treated with 200 mL of distilled water until complete dissolution. The solution was filtered by using a Sep-Pak C18 cartridge activated with 5mL of methanol and 5 mL of distilled water. The two eluates were dried, re-suspended in a solution of trifluoroacetic acid (TFA) 1% (v/v) and analyzed by high performance liquid chromatography (HPLC). Chromatographic separation was performed using an HPLC apparatus:

 

Determination of biochemical constituents:

The carbohydrate content of different varieties was analyzed by anthrone method. The total fibre and lipids were determined by AOAC. The protein content was determined by Lowry method. The antioxidant was assessed by DPPH assay. The total phenol contents of the extracts were determined by mixing (0 - 1.0 ml) of the extracts with equal volume of water; 2.5 ml Folin-Ciocalteau’s reagent and 2 ml of 7.5% sodium carbonate were subsequently added, and the absorbance was read at 765 nm after incubating at 45°C for 40 min. The amount of phenols in the extracts was expressed as gallic acid equivalent (GAE)[14].

 

RESULTS AND DISCUSSION:

HPLC analysis:

The white and purple colored extract of eggplant peels was filtered by using a Sep-Pak C18 cartridge, obtaining a first elution in methanol (Solution B colored in light brown) and a second in distilled water (Solution A colored in dark purple). Both eluates were dried and weighed the amount of 0.603grams for the dry residue A and 0.2034 grams for the dry residue B. The two samples were resuspended and analyzed by HPLC [4,7].

 

The presence of peaks showed delphinidin 3-[4-(cis-p-coumaroyl)-L-ramnosil (1,6) glucopyranoside]-5-glucopyranoside (cis-nasunin) and delphinidin 3-(4-(trans-p-coumaroyl)-L-ramnosil (1,6) glucopyranoside)-5-glucopyranoside (trans-nasunin). The peaks confirmed the presence of nasunin similar results reported by Takashi et al., 2005[8]. The presence of Nasunin was also confirmed by GC-MS analysis .The spectrum MS showed the peak of molecular mass m/z 917 and other peaks of fragmentation at m/z 756 (loss of hexose group), m/z 464 (loss of the group p-coumaroylhexose), m z 302 (loss of the group of delphinidin).

 

The Nasunin is the most important anthocyanin present in the purple eggplant peels at a concentration of 709 mg/100 g and is responsible for the purple color of this vegetable. The low amount of nasunin was found to be 378 mg/100g in white small egg plant peel. The purple colored peel showed a high antioxidant activity [15,16] and a powerful scavenger of hydroxyl radicals and superoxide radicals [17,18}

 

Figure 1: Biochemical constituents of different varieties of eggplant peels

 

The biochemical constituents of carbohydrates was found to be high in long dark purple variety of peel (28.52mg/g) and low was observed in small white coloured variety (10.84mg/g) (Figure1). The dark purple coloured eggplant peel showed high amount of protein and low amount of lipids. All varieties have a significant range of total fibres ranges from 28mg/g to 34 mg/g. Total phenol was observed as low in pure white variety and found to be moderate in green varieties and high in dark purple varieties. A study on extracts prepared from the dark purple eggplant peel showed a greater presence of soluble phenolic compounds than the light violet and striped type and the ability to inhibit DPPH radical was greater in all the extracts prepared from the different varieties of coloured eggplant peels than in those prepared from the white coloured peel. It is important to state that the polyphenols commonly present in the human diet are not necessarily the most active within the body. This fact is due to the presence of low bioavailability, since they are little absorbed by the intestine, highly metabolized, or eliminated quickly. Furthermore, the metabolites found in blood and specific organs, which result from a liver or digestive activity, may differ from ingested substances in terms of biological activity[19,20]. Variations in phenolic content concentrations between several studies occur due to different growing conditions. Several studies have also demonstrated that the Nasunin may prevent the toxic effects of Paraquat, a pesticide that can cause damage (oxidative stress) in several organs such as liver, lungs, kidneys and heart [21].

 

There are many phytochemicals were identified by GC-MS. The dark purple peels showed different forms of esters and polyphenols and ethers when compared with green colored eggplant peels Many compounds exhibit anti-diabetic, antiulcer, anti-hyperlidemic anticancer and antitumor properties (Table 1).

 


 

Table 1: Phytochemicals Identification in dark purple peel by GC-MS.

S. No

RT

Peak Area

Components

1

10.052

6.65

1- Tetradecene 7-Hexadecane,3-Hexadecane

2

11.590

11.28

2,4- bis-1-dimethyl ethyl

3

12.489

9.87

7- Hexadecene 4-Heptaflorobutyryl oxy hexadecane

4

14.665

9.32

5- Octadecene Trichloroacetic acid

5

15.995

5.40

Pentadecanoic acid 14-methyl ester

6

16.634

11.73

Phthallic acid –heptyl 3-yl isobutyl ester

7

16.364

7.89

9- Elcosene

8

17.570

6.10

9,10 Octadecadienoic acid methyl ester

9

17.629

9.08

9,- Octadecenoid acid methyl ester

10

17.949

8.12

Octacosane;Eicosane;Heneicosane

11

18.432

6.71

Trifluoroacetoxy hexadecane,Dichloroaceticacid, Heptadecyl heptafluorobutyrate

12

18.788

7.49

1,1,3- Ter phenyl -2-ol

13

20.096

4.76

2- Chloropropionic acid;Octadecyl ester,Heptfluorobutyric acid hexadecyl ester, Dicloroacetic acid heptadecyl ester

 

Table 2: Phytochemicals Identification in green peel by GC-MS

S. No

RT

Peak Area

Components

1

10.052

6.65

1-Tetradecene 7-Hexadecane, 3-Hexadecane

2

11.990

11.29

Phenol 2,4-bis-1-dimethyl ethyl

3

12.499

9.97

9-Eicosene,3-Octadiene 1-Nonadecene

4

12.570

3.55

Diehyl phthalide,Phthalic acid,butyl tetradecyl ester

5

13.908

10.60

Tritetracontane,10-Methylnonadecane, Nonadecane

6

14.665

10.65

3-Eicosene,5-Octadecene,1-Nonadecene

7

16.374

9.49

Phthalic acid butyl methyl ester,Phthalic acid cyclohexyl,isohexyl ester

8

16.634

8.21

Trichloroacetic acid,tetradecyl ester

9

17.956

5.28

Tetracosane, 2-Bromododecane, Heneicosene

10

18.432

9.42

3-Eicosene,1-Heneicosanol,oxirane

11

20.096

6.22

1- Heptacosanol, Pentafluoropropionic acid, heptade

 

Figure: 2 GC-MS Analysis of Green Colored Eggplant peel

 

Figure: 3 GC-MS Analysis of Dark Purple Coloured Eggplant peel

 


CONCLUSION:

In the present work were described the use of Nasunin as natural antioxidant in eggplant peels. It shows unique characterization of this substance and to nutritional aspects of different coloured eggplant peels. The maximum anthocyanin extracted from dark purple colored eggplant peels and many new phytochemicals were identified by GC-MS. It shows many therapeutic applications in medicine. The use of eggplant peels to extract the anthocyanin, Nasunin, could promote there cycling of waste materials by reducing the environmental impact.

 

REFERENCES:

1.       Lawande KF, Chavan JK Eggplant (Brinjal). In: Salunkhe DK, Kadam SS. Handbook of Vegetable Science and Technology: Production, Composition, Storage, and Processing. Marcel Dekker, New York 1998; 225-44.

2.       Kashyap V, Kumar SV, Collonnier C, Fusari F, Haicour R, et al. Biotechnology of eggplant. Sci Hortic,2003; 1-25.

3.       Lans C Comparison of plants used for skin and stomach problems in Trinidad and Tobago with Asian ethnomedicine. J Ethnobiol Ethnomed2007; 3: 3.

4.       Zhang Y, Hu Z, Chu G, Huang C, Tian S, et al. Anthocyanin accumulation and molecular analysis of anthocyanin biosynthesis-associated genes in eggplant (Solanum melongena L.). J Agric Food Chem 2014; 62: 2906-2912.

5.       Kaneyuki T, Noda Y, Traber MG, Mori A, Packer L, Superoxide anion and hydroxyl radical scavenging activities of vegetable extracts measured using electron spin resonance. Biochem. Mol. Biol. In t1999; 47:979-989.

6.       Noda Y, Kneyuki T, Igarashi K, Mori A, Packer L Antioxidant activity of nasunin, an anthocyanin in eggplant peels. Toxicology 2000; 148: 119-128.

7.       Sadilova E, Stintzing FC, Carle R Anthocyanins, colour and antioxidant properties of eggplant (Solanum melongena L.) and violet pepper (Capsicum annuum L.) peel extracts. Z Naturforsch C 2006; 61: 527-535.

8.       I. Takashi, K. Yoshiki, S. Yasuo, I Yasumasa, K. Takao, K. Tetsuya Nasunin from Eggplant Consists of Cis-Trans Isomers of Delphinidin 3-[4-(p-Coumaroyl)-L-rhamnosyl (12-6) glucopyranoside]-5-glucopyranoside J Agric Food Chem 2005;53: 9472-9477

9.       Basuny AM, Arafat SM, El-Marzooq MA. Antioxidant and antihyperlipidemic activities of anthocyanins from eggplant peels. Journal of Pharma Research and Reviews. 2012: 2(3):50-57.

10.     Gonçalves MC, Diniz MF, Borba JD, Nunes XP, Barbosa-Filho JM. Berinjela (Solanum melongena L.)–mito ou realidade no combate as dislipidemias? Rev Bras Farmacogn. 2006: 16(2): 252-257.

11.     Akamura S, Watanabe S, Obata Y The structure of the major anthocyanin in eggplant Agric Biol Chem ,1963, 7: 663-665.

12.     Kuroda CM. Wada The colouring matter of eggplant (Nasu). Part II. Proc Imp Acad (Japan) 1935,11:235-237

13.     Lydia Ferrara A case of allergy and food sensitivity: the nasunin, natural color of eggplant JOSR Journal of Pharmacy, 2015; 5, (10): 54-58

14.     Harborne JB. Phytochemical methods: a guide to modern techniqus of plant analysis. London: New York: Chapman and Hall; 1973.

15.     Kahkonen, MP Heinonen M Antioxidant activity of anthocyanins and their aglycons J Agric Food Chem 2003;51:628-633

16.     N. Yasuko, K. Takao, I. Kiharu, M. Akitane P., Lester Antioxidant activity of nasunin, an anthocyanin in eggplant peels Toxicology 2000, 148:119-123

17.     Gallo Daniele Navigliolydia Ferrara Nasunin, an antioxidant anthocyanin from eggplant peels, as natural dye to avoid food allergies and Intolerancesmonica European scientific journal March 2014, 10(9), 1-11

18.     Hanan G Sary, Nisha A, Ayqub et.al, Isolation of bioactive compounds from Centaurea aegyptiaca, Int. J. Pharmacy and pharmaceutical sciences 2018, 10(4):1-6.

19.     C. Tateyama, K. Igarashi Anthocyanin and chlorogenic acid contents of some selected eggplant (Solanum melongena L.) cultivars, and the radical scavenging activities of their extracts Nippon Shokuhin Kagaku Kogaku Kaishi, 2006, 53, 218-224

20.     Kimura, Y., Araki, Y., Takenaka, A., Igarashi, K., Protective effects of dietary nasunin on Paraquat-induced oxidative stress in rats. Biosci Biotechnol Biochem 1999; 63 (5):799-804.

21.     Prashant Arya Antioxidant and phytochemical aspects of Himalayan herbal Perstropic Bcalyculata leaves against respiratory infections Int. J. Pharmacy and pharmaceutical sciences 2018,10(3):16-21.

 

 

 

 

 

Received on 20.02.2019          Modified on 10.03.2019

Accepted on 06.04.2019        © RJPT All right reserved

Research J. Pharm. and Tech. 2019; 12(6): 2881 – 2884.

DOI: 10.5958/0974-360X.2019.00485.2