Description:
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.