Abstract:
It has been reported that 11 endolichenic fungal strains were isolated
from lichen, Pseudocyphellaria sp. Endolichenic fungi live asymptomatically within the lichen thallus
and known as a new source useful of bioactive secondary metabolites. Secondary metabolites in
endolichenic fungi show distinct bioactivities including antimicrobial, anti-inflammatory, analgesic,
antioxidant and cytotoxic activities. These bioactive compounds have potential importance in
development of pharmaceutical drugs, nutraceuticals and agrochemicals. The present study was
carried out to investigate antioxidant activities of secondary metabolites produced from Hypoxylon
anthochroum inhabiting the lichen, Pseudocyphellaria sp. In this research, H. anthochroum was
cultured in 50 large petridishes containing potato dextrose agar (PDA) medium and incubated at room
temperature for seven days. After the incubation period, secondary metabolites were extracted into
ethyl acetate in order to obtain crude extract. The crude extract was partitioned using solvents hexane,
chloroform and 60% aqueous methanol. Antioxidant activities of three fractions were evaluated using
micro plate DPPH assay. Since chloroform fraction showed the highest antioxidant activity (81.96 %
Inhibition at 800 μg/mL) it was further subjected to silica gel column chromatography and preparative
thin layer chromatography to isolate bioactive compounds. One UV active pure compound which has
antioxidant activity (43.21 % Inhibition at 800 μg/mL) was isolated from chloroform fraction and its
structure elucidation will be carried out using 1H NMR, 13C NMR, and 2D NMR spectral data.
