“In vitro antimicrobial studies were conducted with aqueous, ethanolic and Petroleum ether extracts of the leaves of Cannabis sativa L. The acidic fraction was obtained from the ethanolic extract and 2% Sodium Hydroxide extract. Ethanolic extract, petroleum ether extract and the acidic fraction exhibited activity both against Gram-positive and Gram-negative bacteria and also against the fungi used in the study. The aqueous extract however, did not show any antimicrobial activity.”

http://www.ncbi.nlm.nih.gov/pubmed/16414764