title: Not only osmoprotectant: betaine increased lactate dehydrogenase activity and L-lactate production in lactobacilli.
abstract: Lactobacilli are commonly used for industrial production of polymer-grade L-lactic acid. The present study tested the Tween 80 alternative betaine in L-lactate production by several industrial lactobacilli. In flask fermentation of Lactobacillus casei, Lactobacillus buchneri, Lactobacillus lactis and Lactobacillus rhamnosus, the betaine addition (2g/l) had similar osmoprotectant effect with Tween 80 but had increased the lactate dehydrogenase activities and L-lactate production than Tween 80 control. In fed-batch fermentation of L. casei, betaine supplementation improved the L-lactic acid titer to 190 g/l, the yield to 95.5% (g L-lactic acid/g glucose), the productivity to 2.6g/lh, and the optical purity to 97.0%. The results demonstrated that supplementation of Tween 80 alternative - betaine in the fermentation medium is feasible for industrial l-lactic acid fermentation by lactobacilli, which will improve the lactate production but will not increase the process costs and modify any process conditions.
authors.affiliation: CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China. Electronic address: zouhb@qibebt.ac.cn.
authors.forename: Huibin
authors.initials: H
authors.lastname: Zou
authors.forename: Zaiqiang
authors.initials: Z
authors.lastname: Wu
authors.forename: Mo
authors.initials: M
authors.lastname: Xian
authors.forename: Hui
authors.initials: H
authors.lastname: Liu
authors.forename: Tao
authors.initials: T
authors.lastname: Cheng
authors.forename: Yujin
authors.initials: Y
authors.lastname: Cao
mesh_terms: D001622:Betaine / Q000494:pharmacology*; D005285:Fermentation / Q000187:drug effects; D007770:L-Lactate Dehydrogenase / Q000378:metabolism*; D019344:Lactic Acid / Q000096:biosynthesis*; D007778:Lactobacillus / Q000187:drug effects / Q000201:enzymology* / Q000254:growth & development; D009995:Osmosis / Q000187:drug effects*; D011136:Polysorbates / Q000494:pharmacology; D020011:Protective Agents / Q000494:pharmacology*
chemical_list: D011136:Polysorbates; D020011:Protective Agents; D019344:Lactic Acid; D001622:Betaine; D007770:L-Lactate Dehydrogenase
keywords: Betaine; Lactate dehydrogenase activity; Lactobacilli; Osmoprotectant; l-Lactic acid