Abstract: In this study,the endophytic fungus Alternaria sp. PQH12 from Artemisia annua was fermented and its mycelia were extracted with different solvents including methanol,acetone,ethyl acetate,n-butanol and cyclohexane.Different tumor cell lines (HL-60, MCF-7 and COLO205) were employed to evaluate the cytotoxic activities of the extracts via MTT assay.In addition,the antioxidant activity of the extract was carried out based on the DPPH radical and O₂· scavenging assays.The results showed that the n-butanol extract (20 μg/mL) was active against HL-60 leukemia cell lines with a growth inhibition of 80.56%,while the ethyl acetate extract (20 μg/mL) was active against MCF-7 breast and COLO205 colon cell lines with a growth inhibition of 54.47% and 83.09%,respectively.The methanol extract exhibited strong DPPH radical and O₂· scavenging activities with IC₅₀ value of 0.20 mg/mL and 0.19 mg/mL respectively.The results suggested that the endophytic fungal Alternaria sp. PQH12 isolated from A.annua exhibited potential cytotoxic and antioxidant activities.

Key words: Artemisia annua, endophytic fungus, Alternaria sp. (PQH12), in vitro cytotoxic activity, antioxidant activity