Microbicidal activity of crude extracts from sargassum wightii against Bacillus cereus.

The present study was investigated to explore the antibacterial activity of four different solvent (petroleum ether, chloroform, acetone and ethanol) crude extracts of marine brown seaweed Sargassum wightti. Crude extracts were screened against human pathogen Bacillus cereus. The antibacterial efficiency was performed by agar well diffusion, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) methods. The results revealed that the crude extract of petroleum ether showed prominent inhibiting activity against B. cereus andother crude extracts showed below detectable level. The highest microbicidal activity (zone of inhibition) 9.0 ± 0.32 mm was obtained at the concentration of 250 μg /ml and the lowest activity was 3 ± 0.20 mm at 31.25 μg /ml concentration. The MIC and MBC values were found to be 125 and 250 μg /ml respectively. Results of this study suggested that the compounds present in the crude extracts of petroleum ether showed high activity against B. cereus and further studies are required to purify the active principles.

Microbicidal activity of crude extracts from Sargassum wightii against Bacillus cereus.

The present study was investigated to explore the antibacterial activity of four different solvent (petroleum ether, chloroform, acetone and ethanol) crude extracts of marine brown seaweed Sargassum wightti. Crude extracts were screened against human pathogen Bacillus cereus. The antibacterial efficiency was performed by agar well diffusion, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) methods. The results revealed that the crude extract of petroleum ether showed prominent inhibiting activity against B. cereus and other crude extracts showed below detectable level. The highest microbicidal activity (zone of inhibition) 9.0 ± 0.32 mm was obtained at the concentration of 250 μg /ml and the lowest activity was 3 ± 0.20 mm at 31.25 μg /ml concentration. The MIC and MBC values were found to be 125 and 250 μg /ml respectively. Results of this study suggested that the compounds present in the crude extracts of petroleum ether showed high activity against B. cereus and further studies are required to purify the active principles.

Microbicides for HIV prevention.

Although the HIV incidence rate has slowed in some countries, HIV remains a serious health challenge, particularly in the developing world. The epidemic is increasingly feminised, with young women at high risk of acquiring the virus. There is thus a clear requirement for acceptable woman-initiated methods of HIV prevention. Foremost among these are vaginally-applied substances known as microbicides; early research into potential microbicides focussed on non-HIV-specific compounds such as surfactants and polyanionic entry inhibitors. However, proof of the microbicide concept as a viable prevention strategy was not provided until the CAPRISA 004 trial of a microbicide containing the HIV-specific antiretroviral tenofovir was completed in mid-2010. Confirmation of the proof of concept provided by CAPRISA 004 by at least two major trials will hopefully lead to licensure of the product by 2018. Parallel studies are planned to ascertain the feasibility of implementation of these products in the public sector with subsequent research focussed on appropriate and acceptable methods of delivery of the active ingredient, and to increase adherence through other delivery systems such as vaginal rings.

Novel Antiviral Agents Targeting HIV Entry and Transmission / 中国病毒学·英文版

Studies of the mechanism of HIV entry and transmission have identified multiple new targets for drug development. A range of inhibitors have demonstrated potent antiretroviral activity by interfering with CD4-gp120 interaction, coreceptor binding or viral-cell fusion in preclinical and clinical studies. One of these agents, fusion inhibitor enfuvirtide, is already in clinical use. Here we review the progress in the development of specific entry inhibitors as novel therapeutics. The potential of entry inhibitors as topical microbicides to block HIV transmission is also discussed.