期刊名称：International Journal of Innovative Research in Science, Engineering and Technology
印刷版ISSN：2347-6710
电子版ISSN：2319-8753
出版年度：2014
卷号：3
期号：4
页码：11406
出版社：S&S Publications
摘要：Lactic acid is widely used in the food, cosmetic, pharmaceutical, and chemical industries and has receivedincreased attention for use as a monomer for the production of bio-degradable polylactic acid. It can be produced by eitherbiotechnological fermentation or chemical synthesis, but the former route has received considerable interest recently, due toenvironmental concerns and the limited nature of petrochemical feed stocks.The recombinant E. coli VK-23 encoding theenzymes of acrylate pathway (lactoyl- CoA dehydratase, acryloyl- CoA reductase and propionyl-CoA transferase) has beendemonstrated earlier for overproduction of lactic acid. In this study we intend to find out the enzymes responsible for lactateoverproduction and to improve the lactate productivity levels by using fed-batch bioreactor. A maximum productivity levelof up to 24.2g l− 1 (% of yield 96%) in 14 hours was obtained with maximum specific and volumetric productivity of 0.8 g g-1h-1 and 2.4 g l− 1 h− 1 respectively. The productivity levels attained seemed to be comparatively similar with that ofmetabolically engineered lactic acid overproducers. This recombinant E. coli with a new acrylate pathway has great potentialto meet the growing market demand of fermentation based lactic acid production due to high growth rate and tolerance toorganic acids.
