No abstract

Antimicrobial triterpenes were isolated from the fruits of Ilex integra. Their structures were elucidated by spectral data and identified as rotundic acid (1), ulsolic acid (2) and peduncloside (3). Triterpene 1 showed significantly broad antimicrobial activity against bacteria, yeast and filamentous fungi. The antifungal activity of 1 was reversed by fatty acids. Cellular constituents leaked from Candida albicans cells incubated with triterpene 1. These results suggest that the antimicrobial activity of triterpenes in I. integra is due to a change of membrane permeability arising from membrane lipid alteration.

Cycloprodigiosin hydrochloride (cPrGW WHCl) obtained from a marine bacterium Pseudoalteromonas denitrificans induces apoptotic cell death in various cancerous cell lines. cPrGW WHCl alone caused a little cytotoxicity in HeLa cells, but it enhanced the apoptotic process progressively when co-administered with tumor necrosis factor (TNF)K K. Here we studied the effect of cPrGW WHCl on TNFK K-induced activation of the transcription factor nuclear factor U UB (NF-U UB). Luciferase gene reporter assays revealed that cPrGW WHCl potently suppressed the TNFK K-and the phorbol myristate acetate-induced activation of NF-U UB. The suppression occurred in the presence of imidazole, indicating that it was not related to the intracellular acidification resulting from the intrinsic H + /Cl 3 symporter activity of cPrGW WHCl. cPrGW WHCl inhibited neither the TNFK K-induced phosphorylation and degradation of inhibitor of nuclear factor-U UB, nor the subsequent nuclear translocation and DNA binding of NF-U UB. cPrGW WHCl also suppressed NF-U UB-enhanced gene expression induced by Rac1, Cdc42, MEKK1, inhibitor of nuclear factor-U UK K (IKKK K), IKKL L, and a subunit of NF-U UB, p65. These results indicate that cPrGW WHCl suppresses NF-U UBdependent gene expression through the inhibition of transcriptional activation. ß 2000 Published by Elsevier Science B.V. on behalf of the Federation of European Biochemical Societies.

No abstract