Effect of seaweeds occurring at Karachi coast on mosquito larvae and liver function in rats.

Seaweeds have been consumed as human food from thousands of years. In this study ethanol extract of 16 different seaweeds were tested for mosquito larvicidal activity against 4th instar larvae of Aedes aegyptii. The ethanol extracts of Padina pavonia and Sargassum ilicifolium caused 50% mortality at 1200ppm concentration. However other seaweeds Halimeda tuna, Ulva lactuca (Chlorophyta), Dictyota dichotoma var intricata, Jolyna laminariodes, Sargassum binderi (Phaeophyta), Melanothamnus afaqhusainii and Solieria robusta (Rhodophyta) showed LC50 at ≈1500 ppm concentration. The n-hexane fraction of Padina pavonia was most potent and produced lethality at minimum concentration (LC50 at 250ppm).The effect of ethanol and water extracts of S. binderii was also examined on liver function of healthy rats. The ethanol extract of Sargassum binderi given orally to rats @ 200mg/kg for 14 days slightly increased the concentration of liver enzymes (ALT, AST, ALP and LDH) and urea level as compared with normal control rats, but did not increase bilirubin, glucose, triglycerides, cholesterol and creatinine. Whereas water extract of S. binderi affected ALT while other biochemical parameters were near normal or slightly decreased as compared to normal control.