Antimicrobial activity of julifloricine isolated from Prosopis juliflora.

Antimicrobial activity of julifloricine, an alkaloid isolated from Prosopis juliflora, was studied in vitro against 40 microorganisms which included 31 bacteria, two Candida species, five dermatophytic fungi and two viruses. Significant inhibitory effect was noted against Gram positive bacteria. The minimal inhibitory concentration (MIC) for Staphylococcus aureus, S. epidermidis, S. citreus, Streptococcus pyogenes and Sarcina lutea was 1 microgram/ml and against S. faecalis, S. pneumoniae, S. lactis, Corynebacterium diphtheriae, C. hofmannii and Bacillus subtilis, 5 micrograms/ml. Its effect was compared with those of identical concentrations of benzyl penicillin, gentamicin and trimethoprim. The inhibitory effect of julifloricine on Gram negative bacteria such as the species of Salmonella, Shigella, Klebsiella, Proteus, Pseudomonas, Enterobacter, Aeromonas and Vibrio was almost insignificant. Julifloricine as compared to micoanzole was found superior against C. tropicalis and responded equally to C. albicans. As compared to econazole, it was found less effective against both C. albicans and C. tropicalis. This alkaloid was found inactive against dermatophytic fungi (up to a dose of 10 micrograms/ml) and viruses which included Herpes simplex 1 and Newcastle disease virus. Julifloricine up to a doses of 1000 micrograms/25 g of mice was found nonlethal.