Evaluation of the potency of endophytic fungi associated with Artemisia annua as antibacterial and antioxidant

Abstract

Artemisia annua has been known as a traditional herbal medicine. The purpose of this study was to evaluate the potential of eight endophytic fungi associated with A. annua as antibacterial and antioxidant. Preliminary screening for antibacterial and antioxidant activities was carried out by the TLC-bioautographic method, and the active extracts were further analyzed for their MIC and IC50 values by serial microdilution method at 96 microwell plates. The results showed that eight endophytic fungi were able to inhibit the growth of Staphylococcus aureus with MIC values ranging from 64 to > 256 μg/ml. In the meantime, five endophytic fungi inhibited the growth of Eschericia coli with MIC values of 256 μg/ml. One isolate, which has a very strong antibacterial activity against S. aureus (MIC = 64 μg/ml), was TdAaCb-2. Four endophytic fungi extracts were active as an antioxidant by acting as DPPH free radical scavengers. The results of this study indicated that the endophytic fungi extracts associated with A. annua were promising natural sources for antibacterial and antioxidant.