Screening of selected wood-damaging fungi for the HIV-1 reverse transcriptase inhibitors

Extracts obtained by using methanol and dichloromethane from 57 species of wood damaging fungi were investigated for their ability to inhibit HIV-1 reverse transcriptase activity in vitro using non-radioactive assay. Sixty tree samples were tested all together; some species were represented by more than one isolate. Thirteen methanol extracts exhibited more than 40% inhibition and two among them inhibited the enzyme more than 80%. All extracts obtained with dichloromethane were inferior to methanolic extracts in their inhibitory activity. The most active fungal species discovered in the first screening were Laetiporus sulphureus and Poria monticola, followed by Poria vaillanti and Chondrostereum purpureum. In the second screening, Laetiporus sulphureus was selected for detailed examination and different isolates were tested. Preliminary findings confirmed a presence of acidic compound with amino group in the most active fraction.