Antiamoebic activity of marine sponge Haliclona exigua (Krikpatrick)

The methanol and methanol-chloroform (1:1) extracts of the freshly collected Haliclona exigua showed minumim inhibitory concentration (MIC) of 125 μg/ml and 250 μg/ml respectively in in vitro studies, but when both of these were tested in vivo in rats, only methanol-chloroform showed 80% inhibition of trophozoites at the dose of 900 mg/kg body weight against Entamoeba histolytica. Therefore only methanol-chloroform extract was further fractionated into four fractions (hexane, chloroform, n-butanol soluble and n-butanol insoluble fractions). Out of these, only hexane and n-butanol soluble fractions showed 80% inhibition of trophozoites at 900 mg/kg dose. Further the chromatography of the n-butanol fraction yielded araguspongin-C which showed promising results at different doses.