In vitro antiplasmodial activity of marine sponge Hyattella intestinalis associated bacteria against Plasmodium falciparum

ABSTRACT

Objective: To identify the antiplasmodial drugs from the marine sponge Hyattella intestinalis (H. intestinalis) associated bacteria. Methods: The H. intestinalis samples were collected from Thondi coast and subjected for enumeration and isolation of associated bacteria. Filter sterilized extracts (100, 50, 25, 12.5, 6.25 and 3.125μg/mL) from bacterial isolates were screened for antiplasmodial activity against P. falciparum and potential extracts were also screened for biochemical constituents. Results: The count of THB isolates were maximum in November 2007 (20×10 4 CFU/g) and the average count was maximum during the monsoon season (77×103 CFU/g). A total of 29 bacteria were isolated based on the morphological characteristics and screened for antiplasmodial activity. The antiplasmodial activity of THB20 extract (IC50 41.88 μg/mL) showed at two fold concentration of IC50 value of the positive control chloroquine (IC50 19.59 μg/mL) and 14 bacterial isolates showed IC50 value of more than 100 μg/mL. Statistical analysis reveals that, significant in vitro antiplasmodial activity (P<0.05) was observed between the concentrations and time of exposure. The chemical injury to erythrocytes showed no morphological changes in erythrocytes by the ethyl acetate extract of THB isolates after 48 h of incubation. The antiplasmodial activity of potential bacterial isolates might be due to the presence of sugars and alkaloids in the ethyl acetate extracts. Conclusions: It is concluded from the present study that, the ethyl acetate extracts of THB20 posses novel metabolites for the development of newer antiplasmodial drugs.