Screening of antioxidant activity of lichens Parmotrema reticulatum and Usnea sp. from Darjeeling hills, India

Abstract

Till date many plants have been screened for their antioxidant activity. Oxidative stress can lead to the production of free radicals which may cause many degenerative diseases. These free radicals can be eliminated with the help of antioxidants which may be of a natural origin. The aim of this study was to examine the antioxidant activity of two common lichens namely Parmotrema reticulatum and Usnea sp from Darjeeling hills. The antioxidant assay of different concentration of ethanolic and methanolic extracts of lichens was determined with respect to five parameters i. e., DPPH radical scavenging activity, total antioxidant activity, reducing power ability, flavonoid and phenolic content. The DPPH radical scavenging ranged from 10% to 31.5% for methanol extracts of Parmotrema reticulatum and Usnea sp respectively and for reducing power measured values of absorbance varied from 0.376 to 0.514. In addition, total phenolic content of the extracts were high and total flavonoids content was moderate. Tested lichen species were found to possess considerable antioxidant activities and could be evaluated as good natural sources of antioxidants.