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采用发酵-渗透汽化耦合(fermentation coupling with pervaporation,FCP)系统和分批补料式发酵系统培养Pseudomonas aeruginosa BC1制备生物表面活性剂鼠李糖脂,两轮发酵过程分别持续124 h和107 h。在FCP系统中,最大细胞吸光度OD600为1.06;生物表面活性剂OD600为0.61;鼠李糖脂最终产量为1.3 g/L,相比于分批补料式发酵系统提高38%;对比纯水的表面张力67.52 m N/m,发酵第29 h的发酵上清液表面张力为22.56 m N/m。同时,该菌的发酵上清液对液体石蜡、机油、柴油、正己烷、十六烷均有较好的乳化能力。经GC-MS结合SPME分析发现,FCP系统分离出的渗透蒸汽冷凝液中含有乙醇、戊醇等有机物。实验结果表明,相比分批补料式发酵系统,FCP系统能够分离发酵过程中产生的一部分挥发性代谢产物,减轻这些物质对细胞生长的抑制,使细胞浓度和鼠李糖脂产量都有明显提高。
The biosurfactant rhamnolipid was cultivated by fermentation coupling with pervaporation (FCP) system and fed-batch fermentation system. The two fermentation processes lasted 124 h and 107 h, respectively. In the FCP system, the maximum cell absorbance OD600 was 1.06; the biosurfactant OD600 was 0.61; the final rhamnolipid production was 1.3 g / L, an increase of 38% compared to the fed-batch fermentation system; The surface tension was 67.52 mN / m. The surface tension of fermentation supernatant at 29 h fermentation was 22.56 m N / m. At the same time, the fermentation supernatant of the bacterium has better emulsifying ability to liquid paraffin, machine oil, diesel, n-hexane and hexadecane. The GC-MS combined with SPME analysis found that the pervaporation condensate separated by FCP system contained organic compounds such as ethanol and amyl alcohol. The experimental results show that compared with fed-batch fermentation system, FCP system can separate some of the volatile metabolites produced in the fermentation process, reduce the inhibition of cell growth by these substances, and significantly increase the cell concentration and rhamnolipid production .