多粘类芽胞杆菌X-11培养条件优化及其对马家柚的促生效果  

Optimization of Culture Conditions of Paenibacillus polymyxa X-11 and Its Growth-Promotion Effects on Citrus maxima L.Osbeck‘Majiayou’

作　　者：于文清 廖雅莉雯 张译心 李珊珊 李鹏[2] 刘文志 YU Wenqing;LIAO Yaliwen;ZHANG Yixin;LI Shanshan;LI Peng;LIU Wenzhi(School of Life Science,Shangrao Normal University,Shangrao Jiangxi 334001,China;Heilongiang Academy of Agricultural Reclamation Sciences,Harbin Heilongjiang 150038,China)

机构地区：[1]上饶师范学院生命科学学院,江西上饶334001 [2]黑龙江省农垦科学院,黑龙江哈尔滨150038

出　　处：《上饶师范学院学报》2024年第3期44-57,共14页Journal of Shangrao Normal University

基　　金：国家自然科学基金项目(32360698、32060633);黑龙江省自然科学基金项目(LH2021C087)。

摘　　要：多粘类芽胞杆菌(Paenibacillus polymyxa)X-11(简称X-11)是本课题组前期研究筛选到的植物根际促生菌,具有固氮、抗菌和促生功能,有开发应用潜力。为优化X-11菌株的培养条件,采用二因素实验设计,通过摇瓶培养试验,研究培养基初始酸碱度(pondus hydrogenii,pH)和培养时间以及培养基装液量和培养温度对X-11菌液活细胞数及其胞外纤维素酶(包括木聚糖酶在内)活性的影响,以及优化培养条件下培养的X-11菌液对马家柚幼苗的促生效应。结果表明:用初始pH8的马铃薯蔗糖液体培养基(potato dextrose broth,PDB)培养40小时(h)时,X-11活细胞的数最多,达4.78×10^(6)菌落形成数/毫升(colony forming units/mL,CFU/mL);用复装液量为35毫升(mL)的复合培养基在35度(℃)培养时,X-11活细胞数最多,达4.47×10^(7)CFU/mL;用初始pH7的PDB培养56 h或48 h时,X-11胞外纤维素酶和木聚糖酶活性均最高,分别达3.93 U(mg/mL/min)和2.26 U;用装液量为20 mL的PDB在25℃培养时,X-11菌液胞外纤维素酶及木聚糖酶活性均最高,分别达5.14 U和3.30 U。采用PDB培养时,X-11培养液活细胞数在初始pH与培养时间之间存在交互作用,但纤维素酶及木聚糖酶活性在初始pH与培养时间之间的交互作用不明显;采用复合培养基培养时,X-11培养液活细胞数在装液量与培养温度之间存在交互作用;采用PDB或复合培养基培养时,X-11胞外纤维素酶活性在装液量和培养温度之间均存在交互作用;采用PDB培养时,X-11胞外木聚酶活性在装液量和培养温度之间存在显著交互作用。综上,X-11菌株接种于初始pH8的复合培养基中、摇瓶装液量为35 mL/100 mL、在35℃培养40 h时,X-11菌液活细胞数显著增加;X-11菌株接种于初始pH7的PDB中、摇瓶装液量为20 mL/100 mL、在25℃培养48 h或56 h时,X-11菌液胞外纤维素酶和木聚糖酶活性显著提高。用收获高活细胞数的优化条件培养的X-11菌液对马家柚(Citrus grandis LPaenibacillus polymyxa X-11(abbreviated as X-11)is a plant rhizosphere growth-promoting bacterium strain screened in the research group's previous studies.This strain has the functions of nitrogen fixation,antimicrobe and growth-promotion,and thus has a potential for development and application.To optimize the culture conditions of strain X-11,a two-factor experimental design was used to study the effects of initial pH of culture medium and culture time,volume of culture medium and culture temperature on the live cell number and the extracellular cellulase(including xylanase)activities of X-11 bacterial suspension through shake flask culture experiments.Then,the growth-promotion effects of X-11 bacterial suspension cultured using the optimized culture conditions on the seedlings of Citrus grandis L.Osbeck were determined.The results showed that,when the initial pH of potato sucrose broth(PDB)medium was 8 and cultured for 40 hours(h),the X-11 bacterial suspension had the highest live cell number,reaching 4.78×10^(6)colony forming units/mL(CFU/mL).When the volume of the composite medium was 35 mL and cultured at 35℃,the X-11 bacterial suspension had the highest live cell number,up to 4.47×10^(7)CFU/mL.When strain X-11 inoculated in PDB medium with the initial pH7,and cultured for 48 h or 56 h,the bacterial suspension had the highest extracellular cellulase and xylanase activities,reaching 2.26 U(mg/mL/min)and 3.93 U,respectively.When the volume of PDB medium was 20 mL and cultured at 25℃,the X-11 bacterial suspension had the highest extracellular cellulase and xylanase activities that reaching 5.14 U and 3.30 U,respectively.When cultured in PDB medium,the live cells number in X-11 bacterial suspension had an interaction effect between initial pH and culture time,while the interaction effect of cellulase or xylanase activity between initial pH and culture time was not significant.When cultured in composite medium,the number of live cells had an interaction effect between the medium volume and culture temperatu

关 键 词：多粘类芽胞杆菌 培养条件 纤维素酶 木聚糖酶 马家柚 

分 类 号：Q939.96[生物学—微生物学]