Premium
Examination of Lactobacillus plantarum lactate metabolism side effects in relation to the modulation of aeration parameters
Author(s) -
Quatravaux S.,
Remize F.,
Bryckaert E.,
Colavizza D.,
Guzzo J.
Publication year - 2006
Publication title -
journal of applied microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.889
H-Index - 156
eISSN - 1365-2672
pISSN - 1364-5072
DOI - 10.1111/j.1365-2672.2006.02955.x
Subject(s) - lactate dehydrogenase , aeration , biochemistry , chemistry , lactobacillus plantarum , metabolism , lactic acid , food science , anaerobic exercise , biology , enzyme , bacteria , organic chemistry , genetics , physiology
Aims: The characterization of global aerobic metabolism of Lactobacillus plantarum LP652 under different aeration levels, in order to optimize acetate production kinetics and to suppress H 2 O 2 toxicity. Methods and Results: Cultures of L. plantarum were grown on different aeration conditions. After sugar exhaustion and in the presence of oxygen, lactate was converted to acetate, H 2 O 2 and carbon dioxide with concomitant ATP production. Physiological assays were performed at selected intervals in order to assess enzyme activity and vitality of the strain during lactic acid conversion. The maximal aerated condition led to fast lactate‐to‐acetate conversion kinetics between 8 and 12 h, but H 2 O 2 immediately accumulated, thus affecting cell metabolism. Pyruvate oxidase activity was highly enhanced by oxygen tension and was responsible for H 2 O 2 production after 12 h of culture, whereas lactate oxidase and NADH‐dependent lactate dehydrogenase activities were not correlated to metabolite production. Limited NADH oxidase (NOX) and NADH peroxidase (NPR) activities were probably responsible for toxic H 2 O 2 levels in over‐aerated cultures. Conclusion: Modulating initial airflow led to the maximal specific activity of NOX and NPR observed after 24 h of culture, thus promoting H 2 O 2 destruction and strain vitality at the end of the process. Significance and Impact of the study: Optimal aeration conditions were determined to minimize H 2 O 2 concentration level during growth on lactate.