Antioxidant properties of methanol extract of a new commercial gelatinous mushrooms (white variety of <i>Auricularia fuscosuccinea</i>) of Taiwan

Abstract

White variety of Auricularia fuscosuccinea is a newly cultivated gelatinous mushrooms which is found only in Taiwan. In this study, total phenolic and total flavonoid content of methanol extract of white variety of A. fuscosuccinea was estimated, and in vitro antioxidant properties and antioxidant enzyme activities were also evaluated. When compared with two other common gelatinous mushrooms, A. polytricha and Tremella fuciformis, white variety of A. fuscosuccinea had the highest total phenolic [7.88 mg gallic acid equivalents (GAE)/g] and total flavonoid [1.60 mg quercetin equivalents (QE)/g]. Among all methanol extracts analyzed, white variety of A. fuscosuccinea had the lowest EC₅₀ value on reducing g power (0.305 mg/ml) and scavenging effect on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical (0.150 mg/ml) had the highest total sugars [44.73 mg dextrose equivalents (DEX)/g] and the lowest EC₅₀ value on chelating effect on ferrous ions (0.427 mg/ml). The methanol extracts from white variety of A. fuscosuccinea possessed the highest superoxide dismutase activity (2.10 U/mg) and total antioxidant capacity (2.26 mM/g). The glutathione reductase activity (7.97 U/g) of A. polytricha was the highest. The analyses of the antioxidant contents phenolic compounds are mainly responsible for the antioxidant effect of gelatinous mushrooms.

Keywords: Auricularia fuscosuccinea, antioxidant activity, reducing power, scavenging effect, chelating effect.