title: Enhanced production of d-lactic acid by Sporolactobacillus sp.Y2-8 mutant generated by atmospheric and room temperature plasma.
abstract: To improve the production of d-lactic acid, atmospheric and room temperature plasma (ARTP) was used to generate mutations in Sporolactobacillus sp. Y2-8. An efficient mutant YBS1-5 was rapidly isolated by implanting ARTP twice with a 100 W radio-frequency power input, 10 standard liters per minute of the helium flow, and a 2 mm treatment distance. Significant improvement of d-lactic acid productivity (1.39 g L(-1) H(-1) ) by YBS1-5 was achieved, and it was 41.84% higher than the productivity (0.98 g L(-1) H(-1) ) of Y2-8. Moreover, the dry cell weight of YBS1-5 was 16.7% higher than that of Y2-8. Metabolic activities of concerned substrates related with key enzymes of d-lactic acid fermentation were analyzed by Biolog approach. Results showed that the activities of the key enzymes glucokinase and d-lactate dehydrogenase in mutant YBS1-5 were increased by approximately 45% and 66%, respectively, in comparison with those of the strain Y2-8. Fed-batch fermentation further improved the productivity; 127 g L(-1) d-lactic acid in 74 H by YBS1-5 with higher productivity (1.72 g L(-1) H(-1) ) was achieved. The subculture experiments indicated that YBS1-5 was genetically stable after eight generations.
authors: College of Biotechnology and Pharmaceutical Engineering, Nanjing Technology University, Nanjing, Jiangsu, People's Republic of China.
authors: Jiaduo
authors: J
authors: Sun
authors: Yan
authors: Y
authors: Wang
authors: Bin
authors: B
authors: Wu
authors: Zhongzhong
authors: Z
authors: Bai
authors: Bingfang
authors: B
authors: He
mesh_terms: D001272:Atmosphere / Q000737:chemistry; D000068536:Bacillota / Q000145:classification / Q000187:drug effects / Q000502:physiology*; D024861:Genetic Enhancement / Q000379:methods*; D019344:Lactic Acid / Q000096:biosynthesis*; D009154:Mutation / Q000187:drug effects / Q000235:genetics; D058626:Plasma Gases / Q000494:pharmacology*; D013045:Species Specificity
chemical_list: D058626:Plasma Gases; D019344:Lactic Acid
keywords: Sporolactobacillus sp; atmospheric and room temperature plasma; d-lactic acid production; high productivity; mutation breeding