Antibacterial Activity of Melittin Purifed from Iranian Honey Bee Venom Against Strains of Acinetobacter baumannii Isolated from Nosocomial Burn Infection

Acinetobacter Baumannii is a dangerous pathogen in many hospitals around the world and is considered an important life threatening factor in burn infections. Nowadays the numbers of multidrug resistance A. baumannii are being rising. In this case, Antimicrobial peptides could be an appropriate solution for treating bacterial infections. Concerning to the problem, this project was aimed to study of antibacterial activity of melittin purified from Iranian honey bee venom on clinical isolates of A. baumannii from hospitalized burn patients.
In this study, A. baumannii strains collected from Shahid Mottahari burn center. Genus and species of the strains were detected by routine methods. Melittin purified from bee venom by Reverse Phase HPLC technique and then lyophilized. Melittin concentration measured by BCA method and the quality of melittin was confirmed using SDS-PAGE. After determining the MIC and MBC of melittin, the results were compared with antibacterial activity of imipenem.
The average of MIC and MBC for melittin in total bacterial population was determined at 0.79 and 1.59 microgram respectively. MIC50, MIC90, MBC50, and MBC90 for melittin calculated as 0.55, 1.1, 1.1 and 2.17 micrograms respectively. In this study, according to the CLSI standard, imipenem-resistant, sensitive, and intermediate strains were 86, 8, and 6 % respectively and also 46% of bacteria had MIC greater than 32 micrograms against imipenem. 100% of the samples had MBC above 32 microgram respectively.
Comparison of inhibitory and bactericidal activity of melittin with imipenem showed that antibacterial activity of melittin is very greater than imipenem. Based on the results it can be concluded that melittin would be used as a preventive or treating agent against colonization of bacteria in burn patients in future.