Free radical scavenging activity of fruiting body extracts of an edible mushroom, Volvariella volvacea (Bull.ex Fr.) Singer: an in vitro study

Mushrooms, being rich source of therapeutic and nutritional substances have received considerable attention for their antioxidant potential. In the present study, methanol (VV MET) and hot water (VV HW) extracts of fruiting bodies of Volvariella volvacea were investigated for free radical scavenging activity. Analysis of antioxidant content of the extracts showed that total phenolics were abundant with 53.13 mg GAEq/g and 36.67 mg GAEq/g in methanol and hot water extracts, respectively. Total flavonoid content in the methanol extract was higher (14.35 mg/g) than the hot water extract (12.54 mg/g). Ascorbic acid levels were 1.72 and 1.52 mg/g in methanolic and hot water extracts, respectively. Reducing power potential of methanol and hot water extracts were 2.11 and 2.38 at 250 mg/ml. 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay exhibited 80.32% inhibition at 250 mg/ml concentration. However, hot water extract showed 74.24% inhibition. ABTS assay showed 68.75 % inhibition for methanol extract and 62.56% for hot water. Hydroxyl radical scavenging activity of hot water extract was maximum (69.34%) when compared to methanol extract inhibition (62.45%). Superoxide and nitric oxide radical inhibition level for methanol extract were found to be 74.23 and 75.25%, respectively at 200ug/ml, whereas hot water extract showed 66.54 and 72.14% inhibition of superoxide and nitric oxide. The study reveals that both the extracts of V. volvacea are having better free radical scavenging potential with high levels of antioxidant compounds