Antishigellosis and Cytotoxic Potency of Crude Extracts and Isolated Constituents from Duranta repens.

The crude ethanol extracts (stem and fruits), their fractions and two triterpenes, ß-Amyrin and 12-Oleanene 3ß, 21ß-diol, isolated as a mixture from the chloroform soluble fraction of an ethanolic extract of Duranta repens stem, were evaluated for antibacterial, antifungal activities by the disc diffusion method and cytotoxicity by brine shrimp lethality bioassay. The structures of the two compounds were confirmed by IR, (1)H-NMR, (13)C-NMR and LC-MS spectral data. The chloroform soluble fraction of stem and ethanol extract of fruits possess potent antishigellosis activity and also exhibited moderate activity against some pathogenic bacteria and fungi but the isolated compound 1 (mixture of ß-Amyrin and 12-Oleanene 3ß, 21ß-diol) showed mild to moderate inhibitory activity to microbial growth. The minimum inhibitory concentrations (MICs) of the extracts (stem and fruits), their fractions and compound 1 were found to be in the range of 32~128 µg/ml. The chloroform soluble fractions of stem and ethanol extract of fruit showed significant cytotoxicity with LC50 value of 0.94 µg/ml and 0.49 µg/ml, respectively against brine shrimp larvae.

In vitro antimicrobial and cytotoxic activities of ferrocene derivative compounds.

The aim of the present study was to investigate the biocidal activity of four new ferrocene derivative based coordination complexes, [1,2,3-trithia-/3/-ferrocenophane, C1]; [disodium-1,1'-ferrocenedithiolate, C2]; [1,1'-(ferrocene-1,1'-diyl)-diethanol, C3]; [ferrocenyl(ethyl-phenyl)-methanol, C4]; against microbes (bacteria and fungi) and brine shrimp (Artemia salina Lech.) nauplii. C2 showed modest antibacterial activity at the concentration of 200 microg disc(-1) and gave its Minimum Inhibitory Concentration values at 32-64 microg mL(-1) against the tested bacteria. These complexes gave comparatively better antibacterial activity against the Gram-positives than the Gram-negatives. C3, C1 and C4 showed moderate antifungal activity at concentration of 200 microg disc(-1). Brine shrimp eggs were hatched in artificial sea water and exposed to the complexes. Median lethal concentration (LC50) values were calculated. Both complexes showed toxicity against brine shrimp but complex C3 explored its potent cytotoxicity having LC50 values at 6.031 microg mL(-1) (ppm).

Cytotoxicity and antimicrobial activity of goniothalamin isolated from Bryonopsis laciniosa.

The cytotoxicity and antimicrobial activity of goniothalamin isolated from Bryonopsis laciniosa was investigated. Goniothalamin showed potent cytotoxicity with LC50 values (5.03 microg/mL) comparable with the reference standard agent, gallic acid. It also showed weak antibacterial and significant antifungal activity against a wide range of gram positive and gram negative bacteria and fungi. The antibacterial (minimum inhibitory concentration) effect against Bacillus cereus and Shigella shiga was found to be 64 microg/mL.