In vitro antiplasmodial activity of Clathria vulpina sponge associated bacteria against Plasmodium falciparum

Objective: To identify the possible antiplasmodial drugs from bacteria associated with marine\udsponge Clathria vulpina (C. vulpina). Methods: The C. vulpina samples were collected from\udThondi coast and subjected to enumeration and isolation of associated bacteria. Filtered and\udsterilized extracts (100, 50, 25, 12.5, 6.25 and 3.125 毺 g/mL) from bacterial isolates were screened for\udantiplasmodial activity against Plasmodium falciparum. Potential extracts were also screened for\udbiochemical constituents. Results: Thirty one bacterial isolates were isolated from twelve sponge\udsamples collected from Thondi coast and screened for antiplasmodial assay. The count of bacterial\udstrains were maximum in November 2007 (19暳 104 CFU/g) and the average count was maximum\udduring the monsoon season (110暳 103 CFU/g). The antiplasmodial activity of isolate THB15 was\udhighly comparable (IC50 = 20.73 毺 g/mL) with the positive control chloroquine (IC50 = 19.59 毺 g/mL)\udand 21 bacterial isolates showed IC\ud50 value of more than 100 毺 g/mL. Statistical analysis reveals\udthat, significant in vitro antiplasmodial activity (P<0.05) was observed between the concentrations\udand time of exposure. The chemical injury to erythrocytes showed no morphological changes in\uderythrocytes by the ethyl acetate extract of bacterial isolates after 48 h of incubation. The in vitro\udantiplasmodial activity might be due to the presence of sugars and alkaloids in the ethyl acetate\udextracts of bacterial isolates. Conclusions: The ethyl acetate extract of THB15 possesses lead\udcompounds for the development of antiplasmodial drugs