Ines Tomoco Kusumoto

HIV-1 reverse transcriptase inhibitory principles from Chamaesyce hyssopifolia

In the course of our studies on the development of anti‐acquired immunodeficiency syndrome (AIDS) agents, we isolated corilagin, quercetin 3‐O ‐β‐D‐glucopyranoside and 1,3,4,6‐tetra‐O ‐galloyl‐β‐D‐glucopyranose from Chamaesyce hyssopifolia, as the main inhibitory substances against human immunodeficiency virus (HIV) reverse transcriptase, an enzyme essential for the proliferation of HIV. The IC50 of these substances were 20, 50 and 86 μM, respectively, their modes of inhibition being non‐competitive with respect to the substrate.

Suppression of hepatitis B virus surface antigen secretion by traditional plant medicines

Forty‐three extracts of herbal medicines were tested for suppressing the secretion of hepatitis B virus (HBV) surface antigen (HBsAg) in vitro. Fourteen extracts were found to have appreciable effects in the experimental system using the PLC/PRF/5 cell line. Of them, the extracts of Rheum palmatum (rhizome), Poligonum cuspidatum (root), Panax japonicum (root) and Terminalia arjuna (bark) strongly suppressed the secretion of HBsAg. The active constituents of these extracts absorbed through the gastrointestinal tract of guinea‐pigs suppressed the secretion of HBsAg in the PLC/PRF/5 cell culture.