试验旨在研究抗菌肽BSN-37的抑菌活性和稳定性.采用微量倍比稀释法测定抗菌肽BSN-37的最小抑菌浓度 (MIC), 菌落计数法分析抗菌肽BSN-37对大肠杆菌CVCC1568的杀菌动力学特征, 扩散法测定抗菌肽BSN-37的盐离子稳定性、酸碱稳定性、血清稳定性、胰酶稳定性、热稳定性、反复冻融稳定性、室温保持稳定性、药效保持时间稳定性.结果显示, 抗菌肽BSN-37对革兰氏阴性菌 (大肠杆菌和沙门氏菌) 的MIC为1.5625～25μg/mL, 对革兰氏阳性菌 (枯草芽孢杆菌和短小芽孢杆菌) 的MIC为1.5625～12.5μg/mL, 对真菌 (白色念珠菌) 没有活性;抗菌肽BSN-37可在90min内完全杀灭大肠杆菌CVCC1568;除了Fe2+和胰酶会影响抗菌肽BSN-37的抑菌活性外, 在75～100℃的高温、150～250mmol/L高浓度盐离子 (Na+、K+、Ca2+和Mg2+) 、20％～25％饱和浓度的Cu2+、pH 4～10、20％～25％的血清、10～12次的反复冻融、10～12d室温保存等条件下仍能保持较好的抑菌活性, 药效保持时间可达7.5d.本试验结果表明, 抗菌肽BSN-37具有替代抗生素成为新抗菌药物的潜力, 为抗菌肽BSN-37的临床应用提供了理论依据.%The aim of the experiment was to study the bacteriostatic activity and stability of the antimicrobial peptide BSN-37.The minimum inhibitory concentration (MIC) of BSN-37 against several bacteria were detected with serial dilution method.The bactericidal dynamics of BSN-37 against Escherichia coli (E.coli) CVCC1568were measured by colony counting method.The salt ion stability, acid-alkali stability, serum stability, pancreatic enzyme stability, thermal stability, repeated freeze-thaw stability, maintain stability at room temperature, and efficacy stabilization stability were analyzed through diffusion method.The results showed that the MIC of the antimicrobial peptide BSN-37 against Gram negative bacteria (E.coli and Salmonella) was 1.5625to25μg/mL, and the MIC of BSN-37 against Gram positive bacteria (Bacillus subtilis and Bacillus pumilus) were 1.5625 to 12.5μg/mL.But BSN-37 had no bacteriostatic activity against fungi (Candida albicans) .The antimicrobial peptide BSN-37 could completely kill E.coli CVCC1568 within 90min.In addition to the Fe2+and pancreatic enzymes could affect the bacteriostatic activity of antimicrobial peptide BSN-37, at other conditions including the high temperature (75to100℃) , 150 to 250mmol/L high concentration of salt ions (Na+, K+, Ca2+and Mg2+) and 20％to 25％ of saturation concentration of Cu2+, pH 4to 10, 20％to 25％ of serum, 10 to 12times of repeated freezing and thawing, preservation for 10 to 12days at room temperature, BSN-37 could still maintain good bacteriostatic activity.Efficacy maintain time of BSN-37 was more than 7.5days.The results provided a theoretical basis for the clinical application of antimicrobial peptide BSN-37 which had a potential to replace antibiotics as new antimicrobial agents.
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