农用抗生素 KA08产生菌182-2的发酵条件优化及其代谢特性

摘要

In order to increase the production of agro-antibiotic KA08 and provide a theoretical basis for scaled production,the fermentation conditions and metabolic properties of its producer strain 182-2 were explored through a single factor test with uniform design method.Results:The inhibitory activity of strain 182-2 was increased by 38.5% when cultivated in the optimum medium instead of the initial one. The optimum fermentation conditions were defined as follows:inoculation amount 4.5%(1.4× 10 7 ~ 10 8 cfu/mL),the volume of media in a 250 mL flask 40 mL,initial pH 7.0,fermentation temperature 28℃, fermentation time 5 d,and seed fungi age 5 d.The fermentation curve showed two semi-coupled peaks in the fermentation process:a mycelium growth peak and an antibiotic formation peak,the former,appearing during 3.5~5.5 d and the latter,during 5~6 d.%为提高农用抗生素 KA08的产量，为其规模化生产提供依据，采用单因素试验和均匀设计方法从碳源及培养基筛选等方面对其产生菌182-2的发酵条件进行优化，并对其代谢特性进行研究。结果表明：182-2菌株采用优化培养基培养，其抑菌活性较原始发酵培养基培养的提高38．5％。最佳发酵条件为250 mL 摇瓶中，装液量为40 mL，菌株182-2的接种量为发酵液总体积的4．5％（1．4×107～108 cfu／mL），初始 pH7，28℃发酵5 d，种子菌龄为5 d。发酵过程中出现菌体生长和抗生素生成2个高峰期，二者属于半耦联型；培养3．5～5．5 d 时菌丝浓度达最大，在5～6d 时抗生素产量达最高。