Antioxidant activity and Folic acid content in indigenous isolates of Ganoderma lucidum

 

Krishna Kondragunta. V, Karuppuraj. V, Perumal. K*

Shri. A.M.M. Murugappa Chettiar Research Centre, Taramani, Chennai- 600113, Tamil Nadu, India

*Corresponding Author E-mail: perumalk@mcrc.murugappa.org

 

ABSTRACT:

Ganoderma lucidum, a medicinal fungus called Linzhi in China and Reishi in Japan, is an economically important fungal species and commonly utilized for its nutraceutical properties. G. lucidum mushroom does not have cyto-toxicity and has been demonstrated to be safe due to its’ long history of oral administration. G. lucidum was subjected to an intensive scientific research since 80s, demonstrating the multiplicity of its medicinal uses and it is a major source for many bioactivities. Among many known and tested bioactive compounds, particularly polysaccharides occupy a precious position as immuno modulators. Anti-oxidant activity of polysaccharides has been identified from G. lucidum. In the present investigation, 4 different indigenous isolates of G. lucidum (GL-01 to GL-04) were tested for its antioxidant and folic acid content. The DPPH radical scavenging activity of G. lucidum was reported and has the maximum antioxidant activity (95.36±0.02%) recorded for GL-01 at 1mg/ml concentration and it is followed by the same strain at 0.8mg/ml concentration (94.92±0.01%). GL-02, GL-03 and GL-04 of methanol extract shown 93.18±0.17, 93.55±0.41 and 92.5±0.34% scavenging activity respectively. The maximum activity with water extract (62.18±1.96%) recorded by GL-03 at 0.8mg/ml concentration. Methanol extract has shown excellent antioxidant potential compare to water extract. Maximum folic acid content (77.7 µg/100g) was recorded in GL-03. The positive results of free radical scavenging activity by fruit bodies of this is another alternative platform to new finding in field of pharmaceutical and nutraceuticals.

 

KEYWORDS: Anti-oxidant activity, Free radical scavenging activity, DPPH, Folic acid and Ganoderma lucidum

 

 


INTRODUCTION:

Free radicals are molecules having an unpaired electron in the outer orbit. They are not stable molecules and ready to react. Free radicals play an important role in living systems. For example, oxygen radicals wield critical actions such as signal transduction and gene transcription. NO is one of the most widespread signalling molecules and participate in every cellular and organic function1. The beneficial effects of free radicals occur at low or moderate concentrations and those levels are balanced by an efficient antioxidant network in the body.

 

The imbalance between this oxidants and antioxidants causes oxidative damage of tissues and bio molecules, eventually leading to disease conditions especially degenerative diseases2. Some antioxidants are produced during metabolism (e.g., glutathione, ubiquinole and uric acid), while many others are obtained from foods in the diet. However, this stockpile of defence mechanical system appeared to weaken considerably with aging. Antioxidants are often reducing agents such as thiols, ascorbic acid, folic acid and polyphenols3. Mushrooms have also been reported as organisms with antioxidant activity. Among medicinal mushrooms, G. lucidum possessed profound antioxidant and anti tumour activities.

 

 

G. lucidum is a medicinal mushroom; the most famous in this group is a legendry mushroom in china, with a long fascinating history dating back over two thousand years. It produces several metabolites such as polysaccharides, triterpinoids, steroids, alkaloids, nucleotides and fatty acids with wide range of biological activity and therapeutic use4. Scientific studies on the extracts and substances from this mushroom demonstrated their anti-ageing, sedative. hepatoprotective, anti-allergic, hypoglycaemic, cardiovascular, Immuno modulatory and anti-viral effects.

 

The present investigation aimed to evaluate the four indigenous strains of G. lucidum for its antioxidant property and Folic acid content. Evaluation of antioxidant activity of methanol and water extracts of different indigenous strains of G. lucidum mushroom was done by DPPH radical scavenging activity. Folic acid is antioxidant which used to prevent cancer during pregnancy. So that the content of folic acid present in G. lucidum were also estimated.

 

MATERIALS AND METHODS:

Collection of plant material and identification

Four fruiting bodies of G. lucidum collected from mushroom production unit, Shri. A.M.M. Murugappa Chettiar research center, Vadakkadampadi and authenticated as the G. lucidum by Karupuraj5.

 

Preparation of Mushroom extracts

The G. lucidum extracts were made using methanol and water by following method as described by the method6. The fruit body of mushroom was sun dried and powdered using mixer grinder to size 5mm. Five grams of dried mushroom was homogenised with 100 ml solvent using shaker at 150rpm and room temperature for 24hrs and filtered through No. 4 Whatman filter paper. The residue was re-extracted twice. The extract was kept for drying at room temperature until get dried completely. The dried extract was re-dissolved at different concentrations in range of 0.2 to 1mg/ml and determined for antioxidant activity.

 

Quantitative assay of DPPH free radical scavenging activity

The scavenging activity for DPPH free radicals was determined according to the method discovered by Zhao et al., 20067. An aliquot of 2 ml of 0.1 mM DPPH solution in ethanol and 1ml of two extracts in different concentration mentioned above were mixed. The mixture was shaken vigorously and allowed to reach a steady state at room temperature for 30 min. Decolourization of DPPH was determined by measuring the decrease in absorbance at 517 nm, and the DPPH radical scavenging effect was calculated according to the following equation:

 

 

Scavenging rate (%) = [(A0 –A1)/ A0] x 100

Where

A0 represents the absorbance of DPPH solution.

A1 represents the absorbance of extract with DPPH solution.

 

Quantification of Folic acid in powder of G. lucidum:

Fruit bodies of G. lucidum (GL-01 to GL-04) were sun dried and powdered using mixer grinder in size 5mm. Extraction procedure was followed by the method8. Three grams of fruit body of G. lucidum was mixed with 30ml of phosphate buffer (0.1M) were immersed in an ultrasonic bath for 15 min. Trichloroacetic acid (TCA) (1ml) acetonitrile (10ml)  added to cleanup mixture and precipitate inferring substances. The total volume was then made up to 50ml with 1M phosphate buffer. The extract was filtered through Whatman filter paper No.1.

 

Folate content in G. lucidum mushroom is followed by the method9. Fruit body extract (50ml) of each mushroom were dissolved in 2ml of 0.1M sodium hydroxide solution. This was reduced using zinc and 1ml of concentrated hydrochloric acid (HCl), filtered and diluted to 100ml using distilled water in 250ml calibrated flask. Aliquots of the working standard solution of reduced Folic acid extract of fruit body were transferred into a series of 25-ml calibrated Flasks. 2ml of 5M HCl was added, cooled, followed by the addition of 2ml of 1% Sodium nitrite (NaNO2) and cooled, and 2 ml of 2% Sulfamic acid was added. The solution was mixed with 2ml of 1% 3-aminophenol, heated in a boiling water bath for 5 min, cooled, followed by the addition of 3 ml of 5M HCl, swirled, and diluted with water to the mark. After the solutions were mixed thoroughly, the absorbance was measured at 460nm. Folic acid was used as standard.

 

RESULTS AND DISCUSSION:

DPPH radical which possesses an unpaired electron and exhibits a strong violet colour in solution (peak absorbance at 517nm) is used as a reagent for evaluation of free radical scavenging activity of anti-oxidants. In present study Methanol shows very good free radical scavenging activity. Free radical scavenging activity of methanol extracts was shown in table1. The maximum activity (95.36±0.02%) recorded for GL-01 at 1mg/ml concentration and it is followed by the same strain at 0.8mg/ml concentration (94.92±0.01%). Minimum activity (52.47%) traced by GL-02 at the concentration 0.2mg/ml.

 

GL-03 and GL-04 noted 93.55±0.41 and 92.50±0.34 activity at the 1mg/ml concentration respectively. The minimum activity of GL-03 observed at 0.2mg/ml concentration is 69.68±0.21%. Table 2 shows results for free radical scavenging activity of water extracts of G. lucidum mushroom powder.


Table 1. Antioxidant activity of Methanol extracts of G. lucidum

Antioxidant activity (%)

Concentration (mg/ml)

GL-01

GL-02

GL-03

GL-04

0.2

56.89±0.44

52.47±1.64

69.68±0.21

53.39±0.91

0.4

76.59±3.05

68.68±2.3

70.62±0.44

67.62±1.31

0.6

87.17±1.68

81.23±0.75

78.93±2.93

76.95±2.27

0.8

94.92±0.01

89.05±1.5

87.39±0.39

90.75±2.32

1.0

95.36±0.02

93.18±0.17

93.55±0.41

92.50±0.34

 

Table 2. Antioxidant activity of water extracts of G. lucidum

Antioxidant activity (%)

Concentration (mg/ml)

GL-01

GL-02

GL-03

GL-04

0.2

35.60±2.14

40.66±0.53

40.46±1.06

43.86±0.83

0.4

41.12±1.11

43.4±0.83

54.99±1.01

51.88±0.79

0.6

42.98±2.08

47.52±2.11

56.88±1.54

54.66±1.52

0.8

44.34±1.21

51.97±0.25

62.88±1.68

54.36±1.14

1.0

40.76±0.51

54.64±0.26

62.18±1.96

51.37±0.74

 


The maximum activity (62.88±1.68%) recorded by GL-03 in 0.8mg/ml concentration and it is almost equal (62.18±1.96%) to the concentration 1mg/ml which is recorded by same strain GL-03.

 

GL-04 followed the GL-03 which recorded 54.66±1.52% of activity at the low concentration 0.6mg/ml and it is followed by GL-02 (54.64±0.26%) which is almost same at the concentration 1mg/ml. Minimum activity against DPPH free radical scavenging activity (35.60±2.14%) observed by GL-01 strain at the concentration of 0.2mg/ml.

 

Methanol extract shown the better scavenging activity compares to the aqueous extracts in each strain and it was observed roughly two times more in methanol extracts. In previous studies it was recorded 93.1% for GL-PS at 0.3mg/ml concentration10, 20.32% at the concentration 1.25mg/ml11, 82.3% by EPS from G. lucidum broth4, 96% by GL polysaccharides12 and it was reported 88.32% for G. lucidum mushroom cultivated on brown rice13. Hence the activity differs from strain to strain and solvent to solvent.

 

Maximum folic acid content (77.7 µg) recorded in GL-03 and followed (54.2 µg) by GL-02. The minimum content observed in the GL-04 strain

 

Table 3: Quantification of Folic acid from Fruit body of G. lucidum

G. lucidum isolates

Folic acid µg/100g

GL-01

48.8

GL-02

54.2

GL-03

77.7

GL-04

41.1

 

CONCLUSION:

Considering the above discussion it can be mentionable that Indigenous isolates of G. lucidum mushroom has the excellent potential of free radical scavenging activity against the DPPH and can be given as the folate supplement as it is considered as one of the anti-oxidant also. Thus G. lucidum can be alternative for anti-oxidant drug.

ACKNOWLEDGMENTS:

The authors thank Shri. A.M.M. Murugappa Chettiar Research Center for providing laboratory facilities to carry out the research activities.

 

REFERENCES:

1.       Fang YZ, Yang S and Wu G. Free radicals, antioxidants, and nutrition. Nutrition. 18(10); 2002: 872-879.

2.       Patel-Rajesh M and Patel-Natvar J. In vitro antioxidant activity of coumarin compounds by DPPH, Super oxide and nitric oxide free radical scavenging methods. Journal of Advanced Pharmaceutical Technology and Research. 1; 2011: 52-68.

3.       Sies H. Oxidative stress: oxidants and antioxidants. Experimental physiology. 82(2); 1997: 291-295.

4.       Mahendran S, Anandapandian KTK, Shankar T, Chellaram C and Vijayabaskar P. Antioxidant properties of Ganoderma lucidum crude exopolysaccharide. Indian J. Innov. Dev, 1; 2012: 1-6.

5.       Karuppuraj V. Studies on Mass production and Nutritional Properties of Edible and Medicinal Mushrooms utilizing available agrowastes.

6.       Tsai SY, Tsai HL and Mau JL. Antioxidant properties of Agaricus blazei, Agrocybe cylindracea, and Boletus edulis. LWT-Food Science and Technology. 40(8); 2007: 1392-1402.

7.       Zhao GR, Xiang ZJ, Ye TX, Yuan Y J and Guo ZX. Antioxidant activities of Salvia miltiorrhiza and Panax notoginseng. Food Chemistry. 99(4); 2006: 767-774.

8.       Furlani RPZ and Godoy HT. Contents of folates in edible mushrooms commercialised in the city of Campinas, Săo Paulo, Brazil. Food Science and Technology (Campinas). 27(2); 2007: 278-280.

9.       Nagaraja P, Vasantha RA and Yathirajan HS. Spectrophotometric determination of folic acid in pharmaceutical preparations by coupling reactions with iminodibenzyl or 3-aminophenol or sodium molybdate–pyrocatechol. Analytical biochemistry. 307(2); 2002: 316-321.

10.     Hu J, Yan F, Zhang Z and Lin J. Evaluation of antioxidant and anti-fatigue activities of Ganoderma lucidum polysaccharides. Journal of Animal and Veterinary Advances. 11(21); 2012: 4040-4044.

11.     Yuan B, Zhang W, Yu Z and Zhang R. In vitro evaluation of antioxidant property of the exopolysaccharides peptides from Ganoderma lucidum CAU5501 in submerged culture. Journal of Food, Agriculture and Environment. 10(1); 2012: 97-101.

12.     Klaus AS, Kozarski MS and Nikšić MP. Antioxidant properties of hot water extracts from carpophore and spores of mushroom Ganoderma lucidum. Zbornik Matice srpske za prirodne nauke (120), 2011: 279-288.

13.     Hasnat MA, Pervin M, and Lim BO. Acetylcholinesterase Inhibition and in Vitro and in Vivo Antioxidant Activities of Ganoderma lucidum Grown on Germinated Brown Rice. Molecules. 18(6); 2013: 6663-6678.

 

 

 

Received on 05.09.2014       Accepted on 18.10.2016     

© Asian Pharma Press All Right Reserved

Asian J. Pharm. Ana. 2016; 6(4): 213-215.

DOI: 10.5958/2231-5675.2016.00032.6