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[structure: see text]. Two novel triterpene dilactones, kadsuphilactones A (1) and B (2), were isolated from the Taiwanese medicinal plant Kadsura philippinensis. The structures of 1 and 2 were elucidated on the basis of extensive spectroscopic methods, including two-dimensional NMR techniques, and confirmed by X-ray crystallographic analysis. Kadsuphilactone B (2) exhibited in vitro anti-HBV activity with IC(50) values of 6 microg/mL by HBsAg enzyme immunoassay.

Hepatitis B virus is associated with chronic or acute liver diseases and with hepatocellular carcinoma. In the present study, we examined the activity of HD-03, a polyherbal formulation, on two hepatitis B surface antigen (HBsAg) expressing human hepatocellular carcinoma cell lines, PLC/PRF/5 and HepG2/A2. We observed that HD-03 downregulates HBsAg expression from these cell lines. Our studies have also shown that this effect is neither due to cytotoxicity on the cell lines nor due to blockade of the release of the antigen from the cells nor due to binding of the substance with the antigen. The possible mode of its antiviral activity is explained., (Copyright 2003 John Wiley & Sons, Ltd.)

With Reid's filtration techniques as a bioassay for evaluating red blood cell (RBC) deformability, we purified from Panax pseudo-ginseng an active component that improved the deformability of calcium-loaded RBC. NMR and mass spectrometric studies showed that the purified substance was a triacylglycerol (TG) with linoleic acid as the major fatty acid residue in the esterified positions of glycerol. The mechanism for this TG to improve RBC deformability could be a modification of membrane fluidity rather than a competitive antagonism with calcium ion.

It has been suggested that Phyllanthus amarus may be helpful in the treatment of hepatitis B virus infection. We studied the effect of an aqueous extract of P. amarus on the cultured hepatoma cell line HepA2. This cell line had been transfected with tandemly arranged HBV DNA and continued to synthesize and secrete both HBsAg and HBeAg. Extract of P. amarus reversibly inhibited cellular proliferation and suppressed HBsAg production but not HBeAg production in HepA2 cells. We also found that P. amarus suppressed HBsAg gene expression at mRNA level in a time-dependent manner, and selectively abolished the HBsAg gene promoter driven CAT activity. Our results demonstrate that P. amarus contains some active components which can suppress the HBsAg gene expression in human hepatoma cells. Such suppression may contribute the antiviral activity of P. amarus in vivo.