Advances in ISSN: 2373-6402APAR

Plants & Agriculture Research
Research Article
Volume 1 Issue 4 - 2014
Wild Mushrooms of Odisha: Prospective Candidates of Antioxidant Sources
Sushri Shant Tripathy, Ashutosh Rajoriya and Nibha Gupta*
Plant Pathology and Microbiology division, Regional Plant Resource Centre, India
Received: July 22, 2014 | Published: August 14, 2014
*Corresponding author: Nibha Gupta, Plant Pathology and Microbiology Division, Regional Plant Resource Centre, Bhubaneswar -751015, Odisha, India, Tel: 0674-2557925; Email: @
Citation: Tripathy SS, Rajoriya A, Gupta N (2014) Wild Mushrooms of Odisha: Prospective Candidates of Antioxidant Sources. Adv Plants Agric Res 1(4): 00021. DOI: 10.15406/apar.2014.01.00021

Abstract

Wild medicinal mushrooms, mostly woody mushrooms comprised Lenzites betulina, Lentinus polychrous, Trametes versicolor, Pycnoporus cinnabarinus, Pycnoporus sp, Inonotus radiatus and Microporus xanthopus were analyzed for antioxidant properties. Of the seven wild mushrooms, Inonotus radiatus had highest content of flavonoid content (13.50±1.33mg/gm), FRAP (1.47±0.09 mg AEAC/gm) and total phenolics content (3.5±0.052mg/gm). Pycnoporus and P. cinnabarinus showed considerably good amount of carotenoids. M. xanthopus showed higher amount of ascorbic acid (5.70±0.01 mg/gm) than other species studied. Results in this study revealed that the composition of all the woody mushrooms are below the phytotoxicity level and ongoing research in this regard can lead for the formulation of drugs in the future.
Keywords: Mushroom; Antioxidant; Ergosterol; Flavonoids

Abbreviations

GAE: Gallic Acid Equivalent; FRAP: Ferric Reducing Antioxidant Power; RSA: Radical Scavenging Assay

Introduction

Antioxidants are compounds that inhibit or slowdowns the oxidation of other molecules by preventing oxidizing chain reactions. Antioxidants can scavenge free radicals and inhibit lipid peroxidation [1-3]. Antioxidants supplementations from fruits and vegetables have been shown to increase level of plasma antioxidant capacities. Similar kind of research has also shown that the intake of plant products lowers the incidences of cancer [2]. Several naturally occurring substances have been known to have antioxidant properties. Flavonoids and other phenolic compounds are among the major components which are present in them which contribute to such sort of activity [4]. Recent studies have highlighted the bioactive compounds obtained from fungi [3], particularly antioxidants [5] which significantly delay or prevent the oxidation of biomolecules in the human body. Mushrooms have been known for functional foods as well as source of physiologically beneficial therapeutic agent, especially antioxidants, β-glucans, polysaccharides and other bioactive substances which are responsible for anticancer, immunostimulating, analgesic and neuroprotective activities. Medicinal mushrooms contain various classes of secondary metabolites with potent antioxidant activity [6,7].
Odisha possess varied range of flora which synergistically or individually supports growth of many macrofungi of edible and/or non edible nature. Although various reports are available regarding antioxidant profiling of edible mushrooms from India but studies related to wild non edible edible mushrooms are very few. Present studies focus mainly on the antioxidant characterization of some wild non edible mushrooms, for which no records are available from Odisha (India).

Materials and Methods

Collection
Mushrooms species of L. betulina, T. versicolor, L. polychrous, P. cinnabarius, Pycnoporus sp, I. radiatus, M. xanthocarpus were collected from tropical moist deciduous and semi ever green forest of Similipal of Mayurbhanj district in India and stored in dried form. Macroscopic and microscopic examination of pileus, stipe, veil, ring, volva, lamellae and gills properties of mushrooms were made to identify species following procedure of Largent et al. [8]. All the assays were performed using the entire mushroom fruiting body including stipe. A fine dried mushroom powder (100mesh) was prepared for each species, stored in the room temperature at 28 °C and used for further biochemical analysis.
Total phenolic content
Total phenolic content in the wild mushrooms were estimated through folin phenol method as described by Singleton and Rossi [9]. 1gm of the powdered sample of each of dried mushroom sample was extracted with 10 ml of absolute methanol by grinded in mortar pestle for effective extraction and centrifuged at 2000 g for 15 minutes. Supernatant collected and stored at 4 °C for further analysis. A sample of 100 µl was made up to 1 ml with distill water and 1 ml of folin ciocalteu reagent and 2 ml of 10% sodium carbonate solution was added to the extract. The total phenolic content in different extract were measured and expressed as gallic acid equivalent (GAE) in gram per 100 gram of sample. Gallic acid was used to draw the standard curve using 10-80 µg (0-0.75 mg/ml) of Gallic acid. The optical density was measured at 765 nm using Analytic Jena spectrophotometer.
Ascorbic acid content
The ascorbic acid content in the wild mushrooms was determined by volumetric method [10]. The dye solution was prepared by dissolving 42 mg of sodium carbonate into a small volume of distill water and 52 mg of 2,6 Dichlorophenolindophenol. The final volume was made up to 200 ml. Sample (0.5-5g) was extracted in 4% oxalic acid and made up to a known volume (100 ml) and centrifuged for 15 minutes. 5ml supernatant from the extract was carefully taken and added with 10 ml of 4% oxalic and titrated against the dye (V2 in ml). The initial and final volume of dye consumed while the appearance of pinkish color for each sample was noted down. The amount of ascorbic acid in mg/ 100 g sample is calculated by using formula; 0.5 mg/V1 ml × V2 /5 ×100/ weight of the sample×100, when V1 is the standard ascorbic acid consumed against dye.
Flavonoids
The flavonoid content of dried sample was estimated by using aluminum chloride colorimetric technique in terms of quercetin equivalents per gram of extract [11]. 0.1ml of methanol extract of samples were diluted with 1.5 ml of methanol and incubated for 5 min at room temperature. 0.1ml of AlCl3 was added and again incubated at room temperature for 5 min. The reaction mixture was mixed with 0.1ml of 1 M Potassium acetate and total volume was made up to 5 ml with distilled water. The mixture was incubated for 30 minutes at room temperature and optical density was measured at 415nm.
Beta carotene and Lycopene
The concentration of β-carotene and lycopene in mushroom extracts was estimated spectrophotometrically following [12,13]. Methanolic extract was evaporated to dryness at 40 °C and about 100 mg of methanolic extract was prepared. The dried methanolic extract i.e., 100 mg was shaken vigorously with 10 ml of acetone and hexane (4:6) for one minute continuously and filtered through whatman filter paper. The absorbance was measured at 453, 505, and 663 nm. The contents of β-carotene and Lycopene were estimated by following formula:
Lycopene: -0.0458 × A.663nm + 0.372 × A.505nm - 0.0806 × A. 453nm.
β-carotene: 0.216 × A.663nm - 0.304 × A.505nm + 0.452 × A.453nm.
Carotenoid
The carotenoid was estimated in 500 mg of dried mushroom powder treated with 10 ml of 80% acetone and centrifuged at 3000 rpm for 10 minutes at 4 °C. This procedure was repeated until the residue became colorless. The residue was made to 10 ml with 80% acetone and measured for absorbance at 480, 645 and 663 nm separately. The quantity of carotenoid was calculated by using following formula and values were expressed in mg/gm by using formula [14]:
Carotenoid = A.480+ (0.114×A.663 - 0.638 × A.645).
Where A= Absorbance.
Tannins
1 gm of mushroom powdered sample was boiled in distilled water for 30 minutes and filtered through whatman filter paper. 0.1 ml of the sample extract prepared by above process was treated with 0.5 ml of Folin Denis reagent. 1 ml of saturated sodium carbonate and 1 ml of distilled water was added to the reaction mixture and shaken well, and the optical density measured at 760 nm. Tannic acid was served as a standard and tannin content estimated was expressed in mg/gm [15].
Alkaloids
1 mg of dried powdered sample was extracted with 100 ml of 10% glacial acetic acid in alcohol. It was filtered and concentrated to 25% of its original volume. A 5 ml amount of the extract solution was adjusted to 2-2.5 pH by adding HCl. 2 ml of Dragendroff’s reagent was added to it, and the precipitate was separated through centrifugation and was further washed with alcohol. The residue was treated with 2 ml sodium sulfide solution. The brownish black precipitate formed was again centrifuged. Completion of precipitation was checked by adding 2 drops of sodium sulfide. The residue was then dissolved in 2 ml concentrated nitric acid which was diluted to 10 ml with distilled water. 1 ml of the solution was added with 5 ml of urea solution and the absorbance was measured at 435 nm [16].
Ergosterol
Sample preparation was done by preparing 1 g dry weight of the fruiting body with 10 ml of mixture of chloroform and methanol (2:1 V/V). Extraction was carried out for 24hrs. Homogenate was filtered and the filtrate was transferred to a separation funnel, shaken well and with 1/5 volume of aqueous NaCl2 (0.9%). The layers were allowed to separate and the lower chloroform phase was collected and used as the test sample. 1ml of sample was evaporated to dryness. 6 ml glacial acetic acid was added to this, immediately followed by mixing 4 ml Ferric chloride reagent. The contents were mixed thoroughly, cooled and the color developed was read at 550 nm against blank. The sterol content was estimated from the standard curve plotted using Ergosterol 10-25 ug/ml [17].

Antioxidant Assay

Free radical scavenging activity
The DPPH activity was estimated in the methanolic extracts by a colorimetric method [18]. 1ml of methanolic extract was added with 2 ml of DPPH solution (1:2) and incubated for 30 minutes in dark after vigorous mixing. Absorbance was measured at 517 nm and scavenging activity of each extract on DPPH radical was calculated.
Reducing power ability
Each mushroom extract (0.5-4mg/ml) in methanol (2.5ml) was mixed with 2.5ml of 200mM sodium phosphate buffer (pH-6.6) and 2.5ml of 1% potassium ferricyanide and the mixture was incubated at 50 °C for 20 minutes. After 2.5ml of 10% trichloroacetic acid was added, the mixture was centrifuged at 2000 rpm for 10 minutes. The upper layer (5ml) was mixed with 5 ml of deionized water and 1 ml of 0.1% ferric chloride and the absorbance was taken at 700nm (Analytic jena) spectrophotometer. Ec 50 value was calculated in mg/ml at 0.5 optical density against reagent blank.
Ferric Reducing Antioxidant Power (FRAP)
100µl of the methanolic extract was mixed with 3ml of FRAP reagent and incubated in the room temperature in dark for 10 minutes and finally absorbance was read at 593nm. FRAP value was expressed in terms of mg AEAC/ gm of sample [19,20].

Results and Discussion

Table 1 represents the antioxidant components of mushroom sp. studied in this research. The total phenol exhibited varied with concentrations ranging from 3.50±0.05 to 0.20±0.01 mg GAE/g of dry extract. Highest phenolic content was estimated in I. radiatus (3.50±0.05mg/gm) followed by Pycnoporus sp. (0.90±0.045 mg/gm) and Pycnoporus cinnabarinus (0.60±0.004mg/gm). We observed low phenolic content in L. polychrous, T. versicolor and L. betulina.
Carotenoid content in the mushroom is relevant to intensity of its color, colorful mushroom showed high amount of the carotenoid content than the colorless ones in our study (Table 2). The highest carotenoid was found in the Pycnoporus sp. (23.93±0.87mg/gm) followed by Pycnoporus cinnabarinus (20.84±1.56mg/gm) and I. radiatus (4.61±1.23mg/gm) where L. polychrous had the lowest concentration (1.31± 0.1mg/gm).
β- carotene is precursor for the synthesis of Vitamin A which acts as powerful antioxidants as well. In general, β- carotene and lycopene are found in rudimentary concentration in mushrooms [21,22]. The content of β- carotene differed considerably between the mushroom species studied, ranging from 0.030mg/gm to 0.693mg/gm, highest β-carotene content was found on P. cinnabarinus (Table 2). Relatively higher lycopene was observed in Pycnoporus sp. i.e. 0.067mg/gm of the dry weight where as lowest lycopene concentration was recorded in Lenzites betulina and I. radiatus (0.008 mg/gm).
The ascorbic acid content of M. xanthopus (5.7±0.010 mg/gm) was more than P. cinnabarinus and T. versicolor 5.0±0.044 mg/gm and 3.9±0.042mg/gm, respectively. Most of the known functions of alkaloids are related to protection or self defence against microbes. Estimation of the alkaloids in the analyzed sample revealed that highest amount of alkaloid in I. radiatus (14.70±2.29) followed by P. cinnabarinus and Pycnoporus sp when L. betulina and L. polychrous (1.45mg/gm and 0.88 mg/gm) contained very small proportion of alkaloid. Ergosterol content acts as a precursor for the formation of Vitamin D and responsible for bone density [23]. Ergosterol content was maximum in Pycnoporus sp followed by L. polychrous and M. xanthopus, respectively. Ergosterol content in I. radiatus was lowest (0.023mg/gm) in our study.
Reducing power of methanolic extracts from wild edible mushrooms increased steadily with increase in concentration (Figure 1). At 4mg/ml, reducing powers were in order of: I. radiatus (1.214)> Pycnoporus sp. (0.5) > M. xanthopus (0.272) > P. cinnabarinus (0.263) > L. polychrous (0.186) > L. betulina (0.173) > T. versicolor (0.166). Except I. radiatus and Pycnoporus sp., all other mushrooms showed very negligible reducing power ability. The reducing power ability of wild edible mushrooms might be due to their hydrogen donating ability.
Figure 1: Reducing power ability of wild medicinal mushrooms.
Concentration dependent scavenging activity was observed in all samples, three mushrooms showing very high radical scavenging assay (RSA). Methanol extract of Pycnoporus sp (84.93%), P. cinnabarinus (73.72%) and L. polychrous (71.09%) can be grouped as high, I. radiatus (57.10%), exhibited moderate whereas species L. betulina (36.71%) and T. versicolor (48.37%) showed very little radical scavenging assay. Pycnoporus sp. represents the lowest IC50 value having and highest DPPH activity (Table 1 and Figure 2).

Species

DPPH in %

IC50 mg/ml

FRAP (mg AEAC/gm)

Lenzites betulina

36.70

> 100

0.24±0.02

Trametes versicolor

48.37

70

0.43±0.01

Lentinus polychrous

71.09

28

0.80±0.08

Pycnoporous cinnabarius

73.72

22

0.12±0.02

Pycnoporous sp.

84.93

13

0.25±0.01

Inonotus radiatus

57.10

54

1.47±0.09

Microporous xanthopus

nd

nd

0.04±0.01

Table 1: Representing antioxidant assay of seven different wild medicinal mushrooms.
AEAC: Ascorbic acid Equivalent Antioxidant Capacity
Where ± represents average and standard deviation of three replicates
Figure 2: Radical scavenging activity of wild medicinal mushrooms.
FRAP value ranged from 1.47 to 0.04 mg AEAC/gm. A high value of FRAP was seen for I. radiatus which also contained maximum total phenolic content and ascorbic acid indicating a strong correlation of these antioxidant component contributing to the bioactivity. It suggested the antioxidant components in these wild mushrooms are capable of reducing oxidants and free radicals. Within the studied mushrooms such as L. polychrous and T. versicolor showed comparatively good FRAP value with those reported from peaches, which ranged from 0.84-1.2 mg AEAC/gm [24] (Table 1).
Highest total flavonoid was observed in I. radiatus (13.50±1.33mg/gm) followed by Pycnoporus sp. and P. cinnabarinus and lowest in L. betulina (0.23±0.15 mg/gm) (Table 2).

Species

Tannins

(mg/gm)

Flavonoids (mg/gm)

β-Carotene (mg/gm)

Lycopene

(mg/gm)

 

Total Phenolic (mg/g)

Ascorbic acid (mg/g)

Ergosterol

(mg/gm)

Alkaloids

(mg/gm)

Carotenoids

(mg/gm)

L. betulina

0.94±0.16

0.23±0.15

0.030±0.000

0.008±0.000

0.30±0.010

2.8±0.037

0.04±0.021

1.45±0.05

1.17±0.27

T. versicolor

0.41±0.08

0.86±0.16

0.159±0.069

0.038±0.003

0.20±0.010

3.9±0.042

0.033±0.010

3.80±0.38

1.30±0.05

L. polychrous

0.47±0.02

0.80±0.01

0.193±0.003

0.023±0.011

0.30±0.007

2.9±0.049

0.046±0.005

0.88±0.17

1.15±0.19

P. cinnabarius

1.33±0.44

5.60±0.65

0.693±0.002

0.060±0.002

0.60±0.004

5.0±0.044

0.033±0.010

5.90±4.60

20.84±1.56

Pycnoporus Sp

2.40±051

11.66±0.90

0.458±0.004

0.067±0.001

0.90±0.045

2.1±0.029

0.066±0.013

4.51±0.13

23.93±0.87

I. radiatus

1.42±0.19

13.50±1.33

0.101±0.005

0.008±0.006

3.50±0.052

3.4±0.022

0.023±0.008

14.70±2.29

4.61±1.23

M. xanthocarpus

1.81±0.42

0.53±0.20

0.059±0.001

0.009±0.001

0.30±0.016

5.7±0.010

0.036±0.005

2.10±1.09

1.07±0.14

Table 2: Representing antioxidant components of wild mushrooms of Odisha in this study.
Where ± represents average and standard deviation of three replicates.
The mushrooms we analyzed especially Pycnoporus sp. and Pycnoporus cinnabarinus contains good amount of carotenoid besides useful phytochemicals such as phenolics, ascorbic acid and other components related to the antioxidant properties.
The methanol extract of Pycnoporus cinnabarinus, Pycnoporus sp. and Lentinus polychrous of eastern India in particular showed the most promising scavenging activity both in term of DPPH scavenging and FRAP assay values. Phenolic compounds at high concentrations may inhibit cell proliferation and simultaneous exposure to hydrogen peroxide. Phenolics have been also shown to lead to the amplification of proliferation inhibition [25]. Our results revealed that total phenolic component and ascorbic acid content of I. radiatus are comparatively appreciable of all our studied mushrooms, 3.50 mg/g and 3.40 mg/gm respectively, which were similar to findings of Anguiano et al. [26] and even the concentration of phenolics is more than the edible variety Pleurotus djamor as reported by Saha et al. [27].
Generally fungi do not possess flavonoid content they have been reported in some macrofungi like Lactarius piperatus [28]. Bioactive compounds as flavonoid content was found to be near about similar 13.50mg/gm (I. radiatus) significant compared to other edible varieties like Ramaria botrytis (16.56 mg/gm) or non edible species as Hypholoma fasciculare (5.09 mg/g) as reported by Barros et al. [29]. Even the concentration of flavonoids was found to be quite high as compared to Agaricus bisporus as reported by Rao et al. [30]. Tannic acid is an example of plant tannins and is polyphenolic- polyhydroxy class of compound. Chemical nature of tannins form complexes with proteins, enzymes and other macromolecules and is generally referred to as an anti-nutrient as well as an antimicrobial agent [31]. Tannic acid content in the mushrooms we analyzed were quite low as compared to the edible varieties as reported by Puttaraju et al. [32], ranging from 2.40±051mg/gm to 0.41±0.08mg/gm.
Results depicted in present study revealed the potential of wild mushrooms of Odisha as a good source of bioactive metabolites specifically when compared with the previous analysis done by Ferreira et al. [33], in addition to that, to best of our knowledge present studies is the first report from the Odisha state of India. Phytochemicals present in the mushrooms after analysis shows that they can be a good alternative source if compared with the plant sources for the health benefits. Present data can be well compared with the results of plant sources as reported by Edeoga et al. [34] which shows that mushroom is the source of medicinally important agents which is no less than many medicinal and edible plant sources [35]. Further studies are targeted towards extraction and purification of these compounds and to evaluate to reach the final conclusion.

Acknowledgement

The financial assistance obtained from Ministry of Environment and Forests, Government of India (Project no. 22-24/2010 CS.I) and Forest and Environment Department Government of Odisha is gratefully acknowledged by the authors.

References

  1. Yashikawa T, Naito Y, Kondo M (1997) Free radicals and disease. In: Hiramatsu M, Yoshikawa T, Inoue M (Eds.), Food and free radicals. Plenum Press, New York, USA, pp. 1119.
  2. Kaur C, Kapoor HC (2001) Antioxidant in fruits and vegetables—the millennium’s health. Int J Food Sci Technol 36(7): 703-725.
  3. Di Piero RM, Novaes QS, Pascholati SF (2010) Effect of Agaricus brasiliensis and Lentinula edodes mushrooms on the infection of passionflower with Cowpea aphid-borne mosaic virus. Braz Arch Biol Technol 53(2): 269-278.
  4. Kang DG, Yun CK, Lee HS (2003) Screening and comparison of antioxidant activity of solvent extracts of herbal medicines used in Korea. J Ethnopharmacol 87(2-3): 231-236.
  5. Cui Y, Kim DS, Park KC (2005) Antioxidant effect of Inonotus obliquus. J Ethnopharmacol 96(1-2): 79-85.
  6. Lee IK, Kim YS, Jang YW, Jung JY, Yun BS (2007) New antioxidant polyphenols from the medicinal mushroom Inonotus obliquus. Bioorg Med Chem Lett 17(24): 6678-6681.
  7. Keles A, Koca I, Genccelep H (2011) Antioxidant properties of wild edible mushrooms. J Food process Technol 2(6): 1-6.
  8. Largent DL, Stuntz DE, Hadley S (1986) How to identify Mushrooms to genus I: Macroscopic features.
  9. Singleton VL, Rossi JA (1965) Colorimetric of total phenolics with phospomolybdic acid reagents. Am J Enol Vitic 16(3): 144-158.
  10. Harris LJ, Ray SN (1935) Determination of plasma Ascorbic acid by 2,6-dichorphenol indophenols titration. Lancet 1: 462.
  11. Chang C, Yang M, Wen H, Chern J (2002) Estimation of total flavonoid content in propolis by two complementary colorimetric methods. J Food Drug Analysis 10(3): 178-182.
  12. Nagata M, Yamishta I (1992) Simple method for simultaneous determination of chlorophyll and carotenoids Tomato fruit. J Japan Soc Food Sci Technol 39(10): 925-928.
  13. Barros L, Venturini BA, Baptista P, Estevinho LM, Ferreira ICFR (2008) Chemical composition and biological properties of Portuguese wild mushrooms: A comprehensive study. J Agric Food Chem 56(10): 3856-3862.
  14. Arnon DI (1949) Copper enzymes in isolated chloroplast, polyphenol oxidase in Beta vulagris. Plant Physiol 24(1): 1-15.
  15. Schanderl SH (1970) In: Method in food analysis academic press, New York, USA, pp.709.
  16. Srividya N, Mehrotra S (2003) Spectrophotometric method for the estimation of alkaloids precipitable with Dragendroff’s reagent in plant materials. J AOAC Int 86(6): 1124-1127.
  17. Sadasivam S, Manickam A (1996) Biochemical methods. Estimation of ergosterol by colorimetric method. (2nd edn), Tamil Nadu, India, pp. 87-88.
  18. Chan EWC, Lim YY, Omar M (2007) Antioxidant and antibacterial activity of leaves of Etlingera Species (Zingiberaceae) in Peninsular Malaysia. Food Chemistry 104(4): 1586-1593.
  19. Benzie IF, Strain JJ (1996) The ferric reducing ability of plasma (FRAP) as a measure of ‘‘Antioxidant Power’’: The FRAP Assay. Anal Biochem 239(1): 70-76.
  20. Athavale A, Jirankalgikar N, Nariya P, Des S (2012) Evaluation of in-vitro antioxidant activity of panchagavya: a traditional ayurvedic preparation. Intern J Pharma Sci Res 3(8): 2543-2549.
  21. Underwood BA, Arthur P (1996) The contribution of vitamin A to public health. FASEB J 10(9): 1040-1048.
  22. Ross AC, Chen Q, Ma Y (2011) Vitamin A and retinoic acid in the regulation of B-cell development and antibody production. Vitam Horm 86: 103-126.
  23. Bouillon RA, Auwerx JH, Lissens WD, Pelemans WK (1987) Vitamin D status in the elderly: seasonal substrate deficiency causes dihydroxycholecalciferol deficiency. Am J Clin Nutr 45(4): 755-763.
  24. Garcia RJ, Parrilla AE, Rosa LA, Mercado G, Dunez DB (2006) Valoracion de la capacidad antioxidante y actividad polifenoloxidasa en duraznos de diferentes areas de produccion 111-116.
  25. Liu F, Ooi VE, Chang ST (1997) Free radical scavenging activities of mushroom polysaccharide extracts. Life Sci 60(10): 763-771.
  26. Anguiano AC, Susana S, Guillermo R, Cristina SR (2007) Radical scavenging activities, endogenous oxidative enzymes and total phenols in edible mushrooms commonly consumed in Europe. J Sci Food Agric 87(12): 2272-2278.
  27. Saha AK, Acharya S, Roy A (2012) Antioxidant level of wild edible mushroom: Pleurotus djamor (Fr.) Boedijn. J Agric Technol 8(4): 1343-1351.
  28. Barros L, Ferreira MJ, Queiros B, Ferreira ICFR, Baptista P (2007) Total phenols, ascorbic acid, β-carotene and lycopene in Portuguese wild edible mushrooms and their antioxidant activities. Food chemistry 103(2): 413-419.
  29. Barros L, Cruz T, Baptista P, Estevinho LM, Ferreira ICFR (2008) Wild and commercial mushrooms as source of nutrients and nutraceuticals. Food Chem Toxicol 46(8): 2742-2747.
  30. Rao JS, Kumar RK, Vale VK, Prasad YP, Saradhi SV (2013) Bioactive molecules and their Anti-oxidant activity of Agaricus bisporus. J Chem Bio Phy Sci 3(2): 1222-1228.
  31. Bhat TK, Singh B, Sharma OP (1998) Microbial degradation of tannins/a current perspective. Biodegradation 9(5): 343-357.
  32. Puttaraju NG, Venkateshaiah SU, Dharmesh SM, Urs SM, Somasundaram R (2006) Antioxidant activity of indigenous edible mushrooms. J Agric Food Chem 54(26): 9764-9772.
  33. Ferreira ICFR, Baptista P, Boas MV, Barros L (2007) Free radical scavenging capacity and reducing power of wild edible mushrooms from north east Portugal: Individual cap and stipe activity. Food Chemistry 100(4): 1511-1516.
  34. Edeoga HO, Okwu DE, Mbaebie BO (2005) Phytochemical constituents of some Nigerian medicinal plants. Afr J Biotechnol 4(7): 685-688.
  35. Onyeka EU, Nwambekwe IO (2007) Phytochemical profile of some green leafy vegetables in south east, Nigeria. Nigerian Food Journal 25(1): 67-76.
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