Abstract

EVALUATION OF ANTIOXIDANT ACTIVITY AMONG THE EPIPHYTIC LICHENS OF KODAIKANAL

Ramya K. and T. Thirunalasundari*

ABSTRACT

Many chronic and degenerative diseases are caused because of the oxidative stress induced due to reactive oxygen species. Phenolic compounds are important part of phytochemicals in natural resources that have high antioxidant ability to scavenge the free radicals and prevent the oxidative stress. There is an increasing attention towards identifying novel and natural antioxidants for treating stress related diseases like cancer, cardiovascular and neurodegenerative diseases. Lichens are one among the natural resources that have exorbitant number of polyphenolic compounds, which place them as good antioxidants. In the present study, the acetone, methanol and ethanol extracts of the lichens; Ramalina conduplicans, Ramalina subpusilla, Parmotrema reticulatum, Parmotrema cristeferum and Usnea cineraria has been screened for their antioxidant potential by standard methods (DPPH radical scavenging, superoxide anion radical scavenging and determination of total phenolic compounds). Effective antioxidant activity was observed among all the lichens tested. The methanolic extract of the lichen, Ramalina conduplicans showed the highest quantity of total phenolic content as well as DPPH radical scavenging activity. Usnea cineraria showed the best superoxide dismutase radical scavenging activity in the acetone extract.

Keywords: Lichens, DPPH, Super oxide dismutase, Total phenols, Antioxidant.