Callus induction in Phyllanthus species and inhibition of viral DNA polymerase and reverse transcriptase by callus extracts.

Studies on callus induction and growth in Phyllanthus amarus Schum. & Thonn. (Euphorbiaceae) and some related species are described, as well as the inhibition of enzymes of hepatitis B and related viruses by callus extracts. Callus was induced from stem or branch pieces of P. amarus placed on several media combinations. Optimum induction and growth of friable, undifferentiated calli occurred on Murashige and Skoog medium supplemented with either 0.5 mg or 1 mg of BA/liter and 1 mg/liter of either 2,4-D or IBA, but not IAA. Callus induction using the same media was also attempted with other Phyllanthus spp. The best success was with P. abnormis. Aqueous extracts from fieldgrown plants were more active in vitro against viral DNA polymerase and reverse transcriptase than extracts of calli.