The objective of this study was to evaluate free radical scavenging
capacity of crude extracts from forest basidiomycetous fungi, domestic
zygomycetous fungi and marine ascomycetous fungi. Lethal concentration
values that kill 50% of the brine shrimps (LC50) were determined from
19 fungal extracts using brine shrimp test (BST). The LC50 values of
fungal extract ranged between 0.28– 40μg/ml. The
basidiomycetous ( Lactarius volemoides ) was the most toxic fungi with
LC50 of 0.28μg/ml while ascomycete Pichia guilliermondii showed
the least toxicity with LC50 of 40μg/ml. The concentrations of
eleven fungal extracts were further evaluated on their ability to
scavenge free radical using 1-diphenyl-2-picrylhydrazyl
(α,α-diphenyl-β-picrylhydrazyl) (DPPH) as a dye reagent
for spectrophotometric assay at 517nm. The extract concentrations that
decreased the initial DPPH radical by 50% (EC50) were determined. The
EC50 values ranged from 19–60.4μg/ml ascorbic acid
equivalents. Extracts from an edible but undomesticated basidiomycetous
fungus isolated from Miombo forest and identified as Termitomyces
microcarpus showed the highest scavenging effect with EC50 at
19μg/ml while that from ascomycete Candida tropicalis showed the
least EC50 at 60.4μg/ml. These results draw attention to wild
undomesticated Miombo fungi as potential source of nutritional
supplements worth further investigation