Abstract

Neeraj Verma, Bhaskar C. Behera, Anjali Sonone and Urmila Makhija

The symbionts of lichen species Arthothelium awasthii, Heterodermia podocarpa, and Parmotrema tinctorum were isolated and cultured on various nutrient media incubated in a growth chamber. Methanolic extracts of one year old symbiont cultures were taken for evaluating their potential to inhibit lipid peroxidation and tyrosinase enzyme activity. The extracts of all cultured lichen-symbionts have shown a concentration-time dependent inhibition of lipid peroxidation and tyrosinase activities. IC50 values for inhibition of lipid peroxidation by culture-extracts were 15.7 µg for A. awasthii, 12.68 µg for H. podocarpa and 11.47 µg for P. tinctorum. Testing the impact of the extracts on tyrosinase activity, we found IC50 of 8.71 µg (A. awasthii), 14.55 µg (H. podocarpa) and 12.44 µg (P. tinctorum). According to their IC50 the tested extracts turned out to be more effective for the tested parameters than the standard antioxidant Trolox (IC50 for lipid peroxidation 16.13 µg) and Kojic acid tyrosinase inhibitor (IC50 for tyrosinase inhibition 17.63 µg). The results suggest possible applications of lichen substances in the extracts of A. awasthii, H. podocarpa, and P. tinctorum symbionts as natural tyrosinase inhibitors.