Effect of high temperature on antibacterial activity of antibacterial substances induced in the house fly (Musca domestica) by pricking

Objective To investigate the effect of high temperature on antibacterial activity of antibacterial substances induced in the larvae of house fly by pricking.Methods The induced hemolymph was bathed at 100℃for 10 sec,30 sec,1 min,3 min,5 min,80℃and 60℃for 30 sec,1 min,3 min,5 min,10 min,then solved in the buffer solution of Na2HPO4-KH2PO4(1/15 mol/L,pH 6.5)and centrifuged,the supernatant was used to test the bacteriostasic efficiency to Micrococcus lysodeikticus and Staphylococcus aureus respectively.Results Diameter of antibacterial ring against M.lysodeikticus decreased along with the increase of bath time at both 100℃and 80℃.No antibacterial ring against S.aureus was found after bathed at 100℃for 1 min or 80℃for 3 min.Diameters of antibacterial ring were similar after bathed at 60℃for different time against both M.lysodeikticus and S.aureus.Conclusion It suggested that the antibacterial activity of antibacterial substance induced by pricking in the house fly was stable against high temperature in a certain extent.Antibacterial activity weakened along with the increase of bath time at 100℃and 80℃,and no obvious change after bathed at 60℃for 10 s-10 min.