拮抗链霉菌R_(2)A-15发酵条件优化及其活性稳定性分析  

Optimization of Fermentation Conditions and Analysis of Activity Stability of Antagonist Streptomyces sp.R_(2)A-15

作　　者：梁嘉振 郭家勇 杨铮蕴 罗婉 罗东程 杨春敏 李羽 谢雨轩 LIANG Jiazhen;GUO Jiayong;YANG Zhengyun;LUO Wan;LUO Dongcheng;YANG Chunmin;LI Yu;XIE Yuxuan(Guangzhou College of Technology and Business,Foshan,Guangdong 528135,China)

机构地区：[1]广州工商学院,广东佛山528135

出　　处：《热带作物学报》2024年第8期1685-1695,共11页Chinese Journal of Tropical Crops

基　　金：广州工商学院2021年度国家级大学生创新创业训练计划项目(No.202113714005);广州工商学院2023年度国家级大学生创新创业训练计划项目(No.202313714005);广州工商学院2022年度校级科研项目(No.KYYB202225)。

摘　　要：柑橘是我国最重要的水果之一,其采后发生的柑橘绿霉病严重威胁柑橘的质量安全,而且还会引起果品中真菌毒素的污染。本团队从广东省湛江市廉江九洲江红橙园的红橙植株根部土壤中,分离筛选出一株对柑橘绿霉病病原菌具有良好拮抗作用的链霉菌R_(2)A-15,对其进行发酵条件优化和抑菌活性稳定性分析,为柑橘绿霉病生防菌剂的制备与应用提供参考。本研究以指状青霉(Penicillium digitatum)为靶标菌,根据纸片扩散法的抑菌圈直径大小判断发酵液抑菌活性。采用单因素和交叉组合试验优化菌株R_(2)A-15发酵培养基,通过响应面分析法对发酵条件进行优化,提高发酵液抑菌活性,并对发酵液进行不同的酸碱、温度和紫外线条件的稳定性研究。在单因素试验和交叉组合试验中,菌株发酵培养基的最适碳源为玉米面,最适氮源为酸水解酪蛋白。根据响应面分析法,得出玉米面和发酵时间对发酵液抑菌活性有显著影响。经验证试验得出,最大的发酵液抑菌活性的最优发酵培养基为:玉米面12.09 g,酸水解酪蛋白4.00 g,碳酸钙2.00 g,硫酸镁2.00 g,磷酸氢二钾2.00 g,氯化钠1.00 g,蒸馏水1 L;最优发酵条件为:发酵初始pH7.0、发酵时间37.50 h、发酵温度34℃、接种量3%、摇瓶装液量100 mL/250 mL。菌株发酵液抑菌活性优化后比优化前提高了39%。菌株发酵液经过不同的温度和紫外线条件处理后,整体抑菌活性能维持在一个相对稳定的高活性水平上,但在强酸强碱条件下,发酵液抑菌活性有所下降。结果表明,链霉菌R_(2)A-15对柑橘绿霉病病原菌具有较好的稳定抑菌效果,有较好的实际应用前景,为后期规模化发酵以及菌剂的开发奠定基础。Citrus is one of the most important fruits in China,and its post-harvest occurrence of citrus green mold is a serious threat to the quality and safety of citrus,and also causes mycotoxin contamination in the fruit.A strain of Strep-tomyces sp.R_(2)A-15 with good antagonistic effect on the pathogen of citrus green mold was isolated from the root soil of red orange plants in the red orange orchard of Jiuzhoujiang,Lianjiang,Zhanjiang city,Guangdong province.The opti-mization of the fermentation conditions and stability analysis of the bacterial inhibition activity were studied to provide reference for the preparation and application of the biocontrol agent of citrus green mold.In this study,Penicillium digitatum was used as the target fungus,and the fermentation broth was used as the inhibitory activity according to the size of the diameter of the inhibition zone by paper diffusion method.The fermentation medium of strain R_(2)A-15 was optimized using one-way and cross-combination tests,and the fermentation conditions were optimized by response sur-face analysis to improve the inhibitory activity of the fermentation broth,and the stability of the fermentation broth was investigated under different acid-base,temperature and ultraviolet light conditions.The optimum carbon source for the fermentation medium of the strain was cornmeal and the optimum nitrogen source was acid-hydrolyzed casein in the one-way and cross-combination tests.Based on response surface analysis,it was concluded that cornmeal and fermenta-tion time had a significant effect on the bacteriostatic activity of the fermentation broth.The optimal fermentation me-dium for maximum inhibitory activity of the fermentation broth,as determined by validation tests,was 12.09 g of cornmeal,4.00 g of acid-hydrolyzed casein,2.00 g of calcium carbonate,2.00 g of magnesium sulfate,2.00 g of dipo-tassium hydrogen phosphate,1.00 g of sodium chloride,and 1 L of distilled water.The optimal fermentation conditions were:initial fermentation pH 7.0,fermentation time 37.50

关 键 词：指状青霉 链霉菌R_(2)A-15 抑菌活性 发酵优化 稳定性 

分 类 号：S436.6[农业科学—农业昆虫与害虫防治]