产抗菌肽乳酸菌筛选及抗菌肽的分离纯化与特性研究

Screening Lactobacillus producing antimicrobial peptides and study on the separation, purification and characterization of antimicrobial peptides

中文关键词:  乳酸菌  抗菌肽  筛选  分离纯化  抑菌特性

英文关键词:lactic acid bacteria  antimicrobial peptides  screening  separation and purification  anti-microbial characterization

中文摘要:

      目的 筛选得到产抗菌肽菌株, 对抗菌肽进行分离纯化及理化性质研究。方法 利用琼脂扩散法筛选产抗菌肽的菌株, 运用细胞吸附解吸和阳离子交换层析法纯化抗菌肽, 从热稳定性、酸碱稳定性和蛋白酶敏感性3方面研究抗菌肽的理化特性。结果 筛选得到7株产抗菌肽的菌株, 其中菌株4121具有较广的抑菌谱, 命名为鼠李糖乳杆菌4121。对抑菌物质进行分离纯化和理化性质测定, 电泳结果显示抗菌肽的分子量约为 11 kDa, 最终获得的抗菌肽比活力为12379.11 AU/mg, 最终纯化倍数为91.99倍。该抗菌肽的抑菌能力在20~80 ℃及偏酸条件下具有很好的稳定性。同时该抗菌肽对蛋白酶K和α-胰凝乳蛋白酶敏感。结论 筛选出的鼠李糖乳杆菌4121所产生的抗菌肽热稳定性及酸稳定性良好, 具有广谱抑菌能力, 并建立了有效的抗菌肽分离纯化法—细胞吸附解吸-阳离子交换层析法。

英文摘要:

      Objective To screen the Lactobacillus producing antimicrobial peptides and isolate and purify the antimicrobial peptides, and research their physicochemical properties. Methods Antimicrobial peptide strains were screened by agar diffusion method. The antimicrobial peptides were purified by cell adsorption and cation exchange chromatography. The physicochemical properties of antimicrobial peptides were studied from 3 aspects: thermal stability, acid and alkali stability and protease sensitivity. Results Seven strains of antimicrobial peptides strains were screened, and the strain 4121 had a broad bacteriostatic spectrum, which was named as Lactobacillus rhamnosus 4121. The bacteriostatic substances were separated and purified and the physical and chemical properties were determinated. Electrophoresis results showed that the molecular weight of the antimicrobial peptides was about 11 kDa, the specific activity of final antibacterial peptide was 12379.11 AU/mg, and the final purified multiple was 91.99 times. The antibacterial ability of antimicrobial peptides in 20~80 ℃ and partial acid conditions had very good stability. Meanwhile, the antimicrobial peptides were sensitive to protease K and α-chymotrypsin. Conclusion The antimicrobial peptides produced by screening 4121 lactobacillus have good thermal stability, acid stability and broad spectrum antibacterial ability. An effective antibacterial peptide separation and purification method-cell adsorption and desorption-cation exchange chromatography is established.