pH值对新型广谱细菌素Garviecin LG34抗菌活性及结构的影响

Effect of pH on Antibacterial Activity and Structure of the Novel Broad-Spectrum Bacteriocin Garviecin LG34

文章研究了pH值对新型广谱乳酸菌细菌素Garviecin LG34抗菌活性和结构的影响,并在此基础上研究细菌素结构与抗菌活性之间的关系。结果表明酸性(pH≤5)和碱性(pH≥8)环境使细菌素Garviecin LG34抗菌活性显著下降(P<0.05)。拉曼光谱分析结果表明细菌素Garviecin LG34的二级结构主要由α-螺旋结构和无规则卷曲结构组成。pH值范围在4.0~6.0,随着pH值的下降α-螺旋结构占比显著下降(P<0.05);pH值范围在7.0~9.0,随着pH值的升高α-螺旋结构占比显著下降(P<0.05)。因此pH值显著影响α-螺旋结构占比和抗菌活性,而且α-螺旋结构占比与细菌素Garviecin LG34抗菌活性之间具有正相关性。

The effect of pH on the antimicrobial activity and structure of garviecin LG34,the novel broad-spectrum bacteriocin from lactic acid bacteria,was researched,on this basis,the relationship between bacteriocin structure and antimicrobial activity was researched.The results showed that the acidic(pH5)and alkaline(pH8)environment significantly decreased garviecin LG34 antibacterial activity(P<0.05).The secondary structure of garviecin LG34 consisted of α-helix and random coli structure by Raman spectroscopy analysis.The proportion of the α-helix structure decreased significantly with pH decreased between 4.0 and 6.0(P<0.05)and with pH increased between 7.0 and 9.0(P<0.05).Therefore,pH significantly affects α-helix ratio and antimicrobial activity,and there is a positive correlation between α-helix ratio and the antimicrobial activity of garviecin LG34.