Biological Properties and Preliminary Purification of Antibacterial Peptide from Tenebrio molitor

[Objective] The aim was to explore the biological properties of antibacterial peptide from Tenebrio molitor.[Method] The antibacterial peptide was induced from larvae of T.molitor by injecting bacteria solution and then they were determined in heat sensitivity,stability by repeated freezing and thawing,suitable pH for antibacterial activity and partial antibacterial spectra,and the antibacterial peptide from T.molitor haemolymph were preliminary isolated and purified.[Result] The antibacterial peptide from T.molitor had good heat stability and repeated freezing and thawing had little influence on its activity,which showed certain acidic and alkali resistances.The antibacterial peptide had best antibacterial effects at pH 5,and they had inhibitory effect on 6 tested animal pathogens at different degree,especially for porcine pathogenic Escherichia coli and Streptococcus suis and they had stronger antibacterial activity on them.Three activity peaks were isolated by SephadexG-25 gel filtration chromatography,which showed that many antibacterial activity components were existed in haemolymph from T.molitor larvae.[Conclusion] The research laid the theoretical basis for utilization of antibacterial peptide from T.molitor.