枯草芽胞杆菌NRCB002发酵液的促生效应及高产乙偶姻发酵条件优化  

Growth promoting effects of fermentation broth and optimization of high-yield acetoin fermentation conditions of Bacillus subtilis NRCB002

作　　者：李林梅 刘柠 马长义 胡椿 李珊珊 沈慧 高南 LI Linmei;LIU Ning;MA Changyi;HU Chun;LI Shanshan;SHEN Hui;GAO Nan(School of Biotechnology and Pharmaceutical Engineering,Nanjing Tech University,Nanjing 211816,China)

机构地区：[1]南京工业大学生物与制药工程学院,江苏南京211816

出　　处：《南京农业大学学报》2024年第6期1105-1112,共8页Journal of Nanjing Agricultural University

基　　金：国家自然科学基金项目(32172673);南京工业大学大学生创新创业训练计划项目(2023DC0694,2024DC1610)。

摘　　要：[目的]本文旨在明确枯草芽胞杆菌发酵液组分对番茄幼苗生长的影响,针对有效代谢产物进行发酵条件优化,为制备高效微生物肥料提供技术支持。[方法]以枯草芽胞杆菌枯草亚种(Bacillus subtilis subsp.subtilis)NRCB002为供试菌株,通过温室盆栽试验,明确NRCB002发酵液组分对番茄幼苗生长和根系形态的影响;以NRCB002菌株生长量及代谢产物乙偶姻产量为评价指标,通过单因素优化法确定碳源和氮源的种类、浓度、发酵温度和发酵时间,通过正交试验设计和极差分析优化无机盐成分。[结果]与去离子水和发酵培养基对照相比,重悬菌液、发酵菌液上清、发酵菌液及含乙偶姻的重悬菌液均显著提高番茄株高、茎粗、叶面积、根冠比、总根长、总根表面积、总根体积、侧根数、地上部和根部的干重;其中,发酵菌液上清及含乙偶姻的重悬菌液处理的番茄幼苗地上部干重显著高于重悬菌液的幼苗地上部干重;发酵菌液上清、发酵菌液及含乙偶姻的重悬菌液处理的番茄幼苗根部干重显著高于重悬菌液处理的幼苗根部干重。以80 g·L^(-1)蔗糖为碳源、以25 g·L^(-1)酵母浸粉为氮源时菌株NRCB002的生物量和乙偶姻浓度均较高;最优无机盐组合:KH_(2)PO_(4)1.5 g·L^(-1)、MgSO_(4)·7H 2O 1.0 g·L^(-1)和MnSO_(4)·H_(2)O 0.2 g·L^(-1);优选的发酵温度为37℃,发酵时间96 h。使用优化后的发酵条件,用1 L摇瓶进行发酵,NRCB002生物量(D 600)为15.70,乙偶姻浓度为29.65 g·L^(-1),分别是初始发酵培养基的3.4和11.8倍。[结论]菌株NRCB002发酵液对番茄生长具有良好的促生作用,乙偶姻是其发酵液中关键的促生物质。[Objectives]The study aimed to investigate the effects of Bacillus subtilis fermentation broth components on the growth of tomato seedlings,optimize fermentation conditions for effective metabolites,and provide technical support for the preparation of efficient microbial fertilizers.[Methods]Bacillus subtilis subsp.subtilis NRCB002 was used as the test strain.A pot experiment was conducted to evaluate the impact of NRCB002 and its fermentation broth components on tomato seedlings.Biomass of NRCB002 and the concentration of acetoin were used as indicators,and single-factor experiments were conducted to optimize type and concentration of carbon and nitrogen sources,the composition of inorganic salts,as well as fermentation temperature and time.The composition of inorganic salt was further optimized by orthogonal experimental design and range analysis.[Results]Compared with control using deionized water and fermentation medium,the NRCB002 fermentation broth supernatant,NRCB002 fermentation broth,resuspended NRCB002 bacteria,and resuspended NRCB002 bacteria with acetoin significantly increased tomato growth parameters,including plant height,stem diameter,leaf area,root-shoot ratio,total root length,total root surface area,total root volume,number of lateral roots,dry weights of tomato shoot and root.This suggested that NRCB002 and its fermentation broth had favorable promoting effects on tomato growth.Furthermore,the tomato shoot dry weights of fermentation broth supernatant,fermentation broth,and resuspended NRCB002 bacteria with acetoin were significantly higher than those of NRCB002 bacteria alone.The biomass and acetoin concentration of NRCB002 strain were higher when using 80 g·L^(-1)sucrose as carbon source and 25 g·L^(-1)yeast extract as nitrogen source.The optimal combination of inorganic salt was 1.5 g·L^(-1)KH_(2)PO_(4),1.0 g·L^(-1)MgSO_(4)·7H_(2)O,and 0.2 g·L^(-1)MnSO_(4)·H_(2)O.The optimal fermentation temperature was 37℃,and the fermentation time was 96 h.Using the optimized fermentation conditi

关 键 词：枯草芽胞杆菌 植物根际促生菌 乙偶姻 发酵条件优化 微生物肥料 

分 类 号：Q815[生物学—生物工程]