ANTIOXIDANT, α-GLUCOSIDASE INHIBITORY AND ANTIFUNGAL ACTIVITIES OF EXTRACTS FROM LICHENS COLLECTED IN VIET NAM

Abstract

Lichens are one of the earliest colonizers of terrestrial habitats on the earth. They are a unique life form of symbiosis between fungi (mycobionts) and algae and/or cyanobacteria (photobionts). Lichens have been used as a cure for diabetes, coughs, pulmonary tuberculosis, wound curing, and dermatological diseases. The aim of this study is to evaluate the antioxidant, α-glucosidase inhibitory and antifungal activities of methanol extracts of lichens from eleven lichen species isolated in Viet Nam including Usnea, Lobaria, and Parmotrema were evaluated. The antioxidant activity was determined by ABTS radical scavenging activities. The results indicated that eleven species of lichens extracts possessed relatively high antioxidant activity with IC50 values ranging from 21.59 to 570.85 µg/ml for 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging assay. The extracts of U101 was more efficient for α- glucosidase inhibitory activity, with the IC50 value of 75.23 ppm. In addition, all extracts also exhibited inhibitory activity on the growth of Aspergillus fumigatus (17.5 – 32.7 %) and Penicillium sp. (16.7 – 33.4 %).