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论文类型：期刊论文

发表时间：2018-10-01

发表刊物：APPLIED MICROBIOLOGY AND BIOTECHNOLOGY

收录刊物：PubMed、SCIE

卷号：102

期号：19

页面范围：8291-8305

ISSN号：0175-7598

关键字：1,3-Propanediol; Microbial consortium; Continuous fermentation; Clostridium butyricum; Stability; Oscillation

摘要：Microbial consortium is an alternative for bioconversion of crude glycerol to value-added products whereas concerns about the process stability in long-term operation existed. The aim of this study is to evaluate the feasibility of using an anaerobic microbial consortium as inoculum for continuous conversion of crude glycerol to 1,3-propanediol (1,3-PDO). Performances of continuous fermentations with the consortium inoculum were evaluated under different dilution rates and glycerol feed concentrations. The highest 1,3-PDO production of 57.86 g/L was achieved with a productivity of 5.55 g/(L.h). Analyses of kinetic data showed that the consortium maintained a consistent pattern for 1,3-PDO production under different operating conditions despite changes in community composition. The continuous fermentation by the consortium was able to operate for a longer period of time (31 volume changes) than that using pure culture (24 volume changes) with the average 1,3-PDO concentration of 53.52 g/L and productivity of 6.69 g/(L.h) under glycerol-excess condition, which could be contributed to the intraspecies diversity among Clostridium butyricum in the consortium. Under glycerol-limited conditions, however, a spontaneous oscillation of the consortium was observed after continuous operation for about 120 h, along with severe fluctuations of the microbial community. The oscillatory behavior could be reduced by increasing the dilution rates and was likely the metabolic feature of C. butyricum.