基于泡沫浮选作用的粘质沙雷氏菌连续发酵
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摘要
粘质沙雷氏菌可用于生产灵菌红素和灵杆菌多糖,具有重要的研究和药用价值,传统生产方法均为批次发酵,产率不高,同时由于发酵过程中会产生大量泡沫,需加入大量消泡剂,不利于下游的提取和纯化操作。为提高产率,去除消泡剂的影响,根据泡沫浮选原理,利用发酵自身产生的泡沫对菌体进行连续分离,收集逃液,实现连续发酵。50 L发酵罐中,装液量为30 L,接种量为2%,通气比为1,搅拌速度为250 r/min,30℃条件下培养,按照8 m L/min的流速流加浓度为发酵培养基5倍(无机盐减半)的补料培养基,可实现连续发酵,培养56 h时,收获菌体总量为批次发酵的2.33倍,灵菌红素总量为批次发酵的2.70倍,发酵液中不含消泡剂,且菌体和灵菌红素集中在逃液中,体积小,便于后续提取、纯化。
Serratia marcescens cell is the source of prodigiosin and hemarisin, which has important research and medicinal value. The traditional production of Serratia marcescens was batch fermentation, but the yield is not high enough, and for the fermentation process produce a lot of foam, operator need to add a lot of defoamer, is not conducive to the downstream extraction and purification. In order to improve the yield and remove the defoamer, inspired by foam flotation method, the Serratia marcescens cells were continuously separated from the broth by foam produced in fermentation, and the escaped broth was collected. According to the following conditions, 50 L fermentation tank, 30 L medium, 2 % inoculation amount, 1 ventilation ratio, 250 r/min stirring speed, 32 ℃, 5 times the nutrients concentration of the fermentation medium(halved the inorganic salts) was supplied as feed medium according to the flow rate of 8 m L/min, continuous fermentation was achieved. After 56 h culture, the total harvest of cells was 2.33 times of that in batch fermentation, the total amount of prodigiosin was 2.70 times of that in batch fermentation, the cells and prodigiosin were concentrated in the escaped broth. The advantage of small size and no defoamer make it easy for follow-up extraction and purification.
Serratia marcescens cell is the source of prodigiosin and hemarisin, which has important research and medicinal value. The traditional production of Serratia marcescens was batch fermentation, but the yield is not high enough, and for the fermentation process produce a lot of foam, operator need to add a lot of defoamer, is not conducive to the downstream extraction and purification. In order to improve the yield and remove the defoamer, inspired by foam flotation method, the Serratia marcescens cells were continuously separated from the broth by foam produced in fermentation, and the escaped broth was collected. According to the following conditions, 50 L fermentation tank, 30 L medium, 2 % inoculation amount, 1 ventilation ratio, 250 r/min stirring speed, 32 ℃, 5 times the nutrients concentration of the fermentation medium(halved the inorganic salts) was supplied as feed medium according to the flow rate of 8 m L/min, continuous fermentation was achieved. After 56 h culture, the total harvest of cells was 2.33 times of that in batch fermentation, the total amount of prodigiosin was 2.70 times of that in batch fermentation, the cells and prodigiosin were concentrated in the escaped broth. The advantage of small size and no defoamer make it easy for follow-up extraction and purification.
引文