一种新微胶囊固定化黄色短杆菌产谷氨酸研究

Cultivation of Brevibacterium flavum in new microcapsule system and production of glutamic acid

针对微生物发酵生产谷氨酸过程中存在的问题,提出了一种固定化微生物发酵生产谷氨酸的新方法.采用硫酸纤维素钠(NaCS)和聚二甲基二烯丙基氯化铵(PDMDAAC)构成:NaCS-PDMDAAC微胶囊,由此微胶囊固定化黄色短杆菌后发酵生产谷氨酸.考察了不同质量浓度葡萄糖对游离和微囊化黄色短杆菌产谷氨酸的影响,并利用微胶囊化的黄色短杆菌进行多批次半连续培养.结果表明,NaCS-PDMDAAC微胶囊与产谷氨酸的黄色短杆菌有很好的生物相容性,与游离培养相比较,微囊化后的黄色短杆菌的生长和产酸功能基本不受影响,容易获得较高的菌体密度,生产效率大大提高,胶囊平均生产能力可达到了15.29 g/(L·h).

Considering the problem of glutamic acid production in microbial culture, a new method of glutamic acid production by Brevibacteriurn flavurn immobilized in microcapsules was put forward. After sodium cellulose sulphate （NaCS） and polydimethyldiallylammonium chloride （PDMDAAC） were synthesized into NaCS-PDMDAAC microcapsules, the glutamic acid was produced by Brevibacteriurn flavurn immobilized in the microcapsules. The effect of glucose concentration on the production of glutamic acid was studied by free and immobilized culture of Brevibacteriurn flavurn, and semi-continuous batch culture of the NaCS-PDMDAAC microcapsules was investigated. The results show that NaCS-PDMDAAC microcapsules and Brevibacteriurn flavurn have good biocompatibility. Compared with free culture, the growth of micro-encapsulated Brevibacteriurn flavurn and the productivity of glutamic acid are not affected, and the microcapsules have advantage of higher cell density and higher productivity of glutamic acid. The productivity per volume microcapsules can reach 15.29 g/（L · b）.