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Indexed by:期刊论文

Date of Publication:2010-08-01

Journal:WORLD JOURNAL OF MICROBIOLOGY & BIOTECHNOLOGY

Included Journals:SCIE、EI、Scopus

Volume:26

Issue:8

Page Number:1401-1407

ISSN No.:0959-3993

Key Words:Oscillation; 1,3-Propanediol; 3-Hydroxypropionaldehyde; Klebsiella pneumoniae; Metabolism

Abstract:Sustained oscillations have been observed in cell growth and glycerol metabolism by Klebsiella pneumoniae during long-term continuous cultivations under anaerobic conditions. However, the oscillation behavior of glucose-glycerol co-fermentation under micro-aerobic conditions has yet not been studied. In this study, the unclear mechanism of oscillation was investigated by using different substrates including glycerol, glucose, and mixtures of glycerol and glucose. A large perturbation of substrate concentration was operated to study the dynamic behavior of continuous fermentation by K. pneumoniae DSM 2026 under micro-aerobic conditions. Oscillations occurred when 80 g of glycerol l(-1) was used as single carbon source or co-substrate with 35 g of glucose l(-1), whereas no oscillation was observed when glucose was used alone. During the oscillation phases, parameters periodically passed maxima and minima at a relatively constant time interval, and the period of oscillation was 10-16 h. The comparison between glycerol and glucose metabolism revealed that a potential mechanism of oscillation lies in the accumulation of 3-hydroxypropionaldehyde, which is toxic to cell growth.