抗菌脂肽BSLP21的分离纯化及其结构与活性分析

Purification and Analysis of Its Structure and Activity of An Antimicrobial Lipopetide BSLP21

对枯草芽孢杆菌FB123产生的脂肽类抗菌物进行了分离纯化、结构鉴定及活性分析。枯草芽孢杆菌FB123发酵液经酸沉淀、Sephacryl S-200凝胶柱层析、反相柱层析、Sephadex LH-20凝胶层析、正相硅胶层析等技术获得抗菌脂肽纯品BSLP21。对BSLP21的抑菌试验发现,BSLP21对水稻致病菌稻瘟病菌具有良好的抑菌效果。对BSLP21表面活性的研究发现,BSLP21具有很好的热稳定性,经100℃处理2 h表现最高活性,排油圈直径达3.13 cm;最适p H值为10,此时排油圈直径达3.32 cm,在p H 6~12范围仍保留最高活性的60%以上;具有一定耐盐性,在Na Cl浓度为15%时,仍具有最高活性的50.8%。BSLP21经质谱及核磁共振分析鉴定为C15的lichenysin A。

In the present study,a lipopeptide antimicrobial compound was isolated and purified from Bacillus subtilis FB123,and its structure was identified and activities were analyzed. An antimicrobial lipopeptide( BSLP21) was purified from the fermentation broth of B. subtilis FB123 by acid precipitation,gel chromatography on Sephacryl S-200,reverse phase chromatography on silica gel column,gel chromatography on Sephadex LH-20 and forward phase chromatography on silica gel. The antimicrobial analysis showed that BSLP21 exhibited good inhibition on rice blast fungus. Analysis of the surface-activity stability indicated that BSLP21 showed high thermal stability and exhibited its highest activity after being treated at 100 °C for 2 h,the diameter of oil spreading reached to3. 13 cm; The optimal p H value of BSLP21 was obtained at p H 10 and showed the oil spreading diameter of 3. 32 cm,with over 61%maximum activity retained at p H 6. 0-12. BSLP21 also showed resistance to salt of Na Cl. It kept 50. 8% of the maximum activity when dissolving in 15% Na Cl. The BSLP21 was identified as C15 lichenysin A by techniques of mass-spectrometric and nuclear magnetic resonance.