Antimicrobial activities of honey bee venom against pathogens isolated from clinical bovine mastitis in Korea

In Korea, honey bee (Apis mellifera, L) venom therapy (apitherapy) has been elucidated therapeutic value for farm animals with bacterial diseases and reported to be as effective as antibacterial drugs. This study was performed by using three honey bee venom products and 44 strains of bacteria isolated from infected cows' mammary quarters with mastitis in Korea. The concentration of major active components of bee venom were analyzed by HPLC and antimicrobial activity and potent were confirmed and compared among the three bee venom products by Cylinder agar plate method and Minimum Inhibitory Concentration (MIC). Time kill assays and electron scanning microscopy were used for observation of pore forming on cell membrane during the bacterial inhibition of the sensitive strains over time. In this study, the concentration of three major active components had a little frustration among three venom products, but the antimicrobial activities were not different statistically. All three products effectively inhibited the growth of Staphylococcus aureus (10 strains), Coagulase-negative Staphylococcus (CNS, 7 strains), and partially inhibited that of E. coli (2 of 7 strains) while didn't inhibit those of the others (at the over 500µg/ml of concentrations). MIC of S. aureus, CNS and E. coli were 62.5˜125, 62.5˜250 and 62.5˜250 µg/ml respectively. However the pore forming on cell membrane wasn't observed by electron scanning microscopy at the time kill assay for the sensitive strains. It is needed to undergo more experimental investigation to ascertain the mechanism of action of antimicrobial activity of bee venom.