Antibacterial activity of two limonoids from Swietenia mahagoni against multiple-drug-resistant (MDR) bacterial strains.

Solvent partitioning followed by column chromatography of the MeOH extract of the seeds of Swietenia mahagoni afforded two limonoids, swietenolide (1) and 2-hydroxy-3-O-tigloylswietenolide (2). The compounds were identified by spectroscopic means. The antibacterial activity of these compounds was assessed against eight multiple-drug-resistant bacterial strains (clinical isolates) by the conventional disc diffusion method. While both compounds were active against all test organisms, compound 2 displayed overall more potent activity than compound 1.

Pachypodol, a flavonol from the leaves of Calycopteris floribunda, inhibits the growth of CaCo 2 colon cancer cell line in vitro.

Calycopteris floribunda Lam., commonly known as 'goichia lata or goache lata', is a large climbing woody shrub from Bangladesh, and well distributed in a number of other south-east Asian countries. Traditionally, C. floribunda has been used in colic, as an antihelminthic, astringent and carminative, and for the treatment of diarrhoea, dysentery, jaundice and malaria in many countries including Bangladesh. Pachypodol (5,4'-dihydroxy-3,7,3'-trimethoxyflavone) has been isolated from the leaves of C. floribunda by repeated column chromatography on silica gel, and the structure confirmed by spectroscopic means. While the general toxicity of pachypodol was determined by the brine shrimp lethality assay, the cytotoxic potential of this flavonoid has been evaluated by the Promega's CellTiter 96 Non-Radioactive Cell Proliferation Assay using the CaCo-2 colon cancer cell line (IC(50) = 185.6 microM). A summary of the biological activities of pachypodol reported to date is also presented.