D-Lactic Acid Production from Xylose in Engineered Escherichia coli SZ470

WD100, knocked out adhE of Escherichia coli SZ470 and inserted ldhA into Escherichia coli WD01, was genetically engineered to utilize xylose. D-lactate production was investigated for shake flask cultures with xylose. In 64h WD100 produce 10.1g/L D-lactate in the shaking flask And it consumed 25g/L xylose during the ending of fermentation.This volumetric productivity with xylose is 0.14 g·L-1·h-1.Because of pyruvate decarboxylase (poxB) expressed in flask fermention,acetate production was up to 4.7g/L.Succinate,formate,ethanol was also produced as a minor product during fermentation.

Download Full-text

The Effects of adhE Deletion on the Metabolism for D-Lactic Acid Production by the Escherichia coli JH11

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.476-478.2051 ◽

2012 ◽

Vol 476-478 ◽

pp. 2051-2054 ◽

Cited By ~ 1

Author(s):

Jin Fang Zhao ◽

Li Yuan Xu ◽

Yong Ze Wang ◽

Jin Hua Wang ◽

Sheng De Zhou

Keyword(s):

Escherichia Coli ◽

Lactic Acid ◽

Carbon Source ◽

Acid Production ◽

Lactic Acid Production ◽

Mineral Salts ◽

E Coli ◽

Recombination System ◽

Recombinant Technology ◽

A Minor

Escherichia coli W produces a mixture of organic acids during fermentation in mineral salts medium using glucose as the sole carbon source. Among these products, D-lactate, acetate, succinate, and ethanol are the majors, with formate as a minor. In order to evaluate the effect of adhE mutation on the metabolism for D-lactic acid production by E. coli W, an adhE deletion mutant JH11 was constructed using the RED recombination system and the flipase recognition target （FRT） site-specific recombinant technology. Compared to the parent strain, JH11 produced significantly higher concentration of D-lactate due to the increased NADH availability, with slightly changed acetate (increased), and succinate (decreased), in fermentations using mineral salts medium containing glucose as the carbon source and calcium carbonate as the neutralizer.

Download Full-text

The Effect of Pyruvate Decarboxylase Gene Knockout inSaccharomyces cerevisiaeonL-Lactic Acid Production

Bioscience Biotechnology and Biochemistry ◽

10.1271/bbb.70.1148 ◽

2006 ◽

Vol 70 (5) ◽

pp. 1148-1153 ◽

Cited By ~ 62

Author(s):

Nobuhiro ISHIDA ◽

Satoshi SAITOH ◽

Toru ONISHI ◽

Kenro TOKUHIRO ◽

Eiji NAGAMORI ◽

...

Keyword(s):

Lactic Acid ◽

Acid Production ◽

Gene Knockout ◽

Lactic Acid Production ◽

Pyruvate Decarboxylase

Download Full-text

Techno-Economic Analysis of Bio-Based Lactic Acid Production Utilizing Corn Grain as Feedstock

Processes ◽

10.3390/pr8020199 ◽

2020 ◽

Vol 8 (2) ◽

pp. 199 ◽

Cited By ~ 3

Author(s):

Ashish Manandhar ◽

Ajay Shah

Keyword(s):

Lactic Acid ◽

Acid Production ◽

Raw Materials ◽

Lactic Acid Production ◽

Chemical Equipment ◽

Genetically Engineered ◽

Economic Feasibility ◽

Production Costs ◽

Conversion Rates ◽

Corn Grain

Lactic acid is an important chemical with numerous commercial applications that can be fermentatively produced from biological feedstocks. Producing lactic acid from corn grain could complement the use of already existing infrastructure for corn grain-based ethanol production with a higher value product. The objective of this study was to evaluate the techno-economic feasibility of producing 100,000 metric tons (t) of lactic acid annually from corn grain in a biorefinery. The study estimated the resources (equipment, raw materials, energy, and labor) requirements and costs to produce lactic acid from bacteria, fungi and yeast-based fermentation pathways. Lactic acid production costs were $1181, $1251 and $844, for bacteria, fungi and yeast, respectively. Genetically engineered yeast strains capable of producing lactic acid at low pH support significantly cheaper processes because they do not require simultaneous neutralization and recovery of lactic acid, resulting in lower requirements for chemical, equipment, and utilities. Lactic acid production costs were highly sensitive to sugar-to-lactic-acid conversion rates, grain price, plant size, annual operation hours, and potential use of gypsum. Improvements in process efficiencies and lower equipment and chemical costs would further reduce the cost of lactic acid production from corn grain.

Download Full-text

Enhancement of D-lactic acid production from a mixed glucose and xylose substrate by the Escherichia coli strain JH15 devoid of the glucose effect

BMC Biotechnology ◽

10.1186/s12896-016-0248-y ◽

2016 ◽

Vol 16 (1) ◽

Cited By ~ 19

Author(s):

Hongying Lu ◽

Xiao Zhao ◽

Yongze Wang ◽

Xiaoren Ding ◽

Jinhua Wang ◽

...

Keyword(s):

Escherichia Coli ◽

Lactic Acid ◽

Acid Production ◽

Lactic Acid Production ◽

Coli Strain ◽

Glucose Effect

Download Full-text

Inhibitory Activity of Cheese Whey Fermented with Kefir Grains

Journal of Food Protection ◽

10.4315/0362-028x.jfp-10-121 ◽

2011 ◽

Vol 74 (1) ◽

pp. 94-100 ◽

Cited By ~ 20

Author(s):

A. LONDERO ◽

R. QUINTA ◽

A. G. ABRAHAM ◽

R. SERENO ◽

G. DE ANTONI ◽

...

Keyword(s):

Escherichia Coli ◽

Lactic Acid ◽

Acid Production ◽

Cheese Whey ◽

Lactic Acid Production ◽

Reaction Products ◽

Salmonella Enterica Serovar Enteritidis ◽

Fermentation Products ◽

E Coli ◽

Kefir Grains

We investigated the chemical and microbiological compositions of three types of whey to be used for kefir fermentation as well as the inhibitory capacity of their subsequent fermentation products against 100 Salmonella sp. and 100 Escherichia coli pathogenic isolates. All the wheys after fermentation with 10% (wt/vol) kefir grains showed inhibition against all 200 isolates. The content of lactic acid bacteria in fermented whey ranged from 1.04 × 107 to 1.17 × 107 CFU/ml and the level of yeasts from 2.05 × 106 to 4.23 × 106 CFU/ml. The main changes in the chemical composition during fermentation were a decrease in lactose content by 41 to 48% along with a corresponding lactic acid production to a final level of 0.84 to 1.20% of the total reaction products. The MIC was a 30% dilution of the fermentation products for most of the isolates, while the MBC varied between 40 and 70%, depending on the isolate. The pathogenic isolates Salmonella enterica serovar Enteritidis 2713 and E. coli 2710 in the fermented whey lost their viability after 2 to 7 h of incubation. When pathogens were deliberately inoculated into whey before fermentation, the CFU were reduced by 2 log cycles for E. coli and 4 log cycles for Salmonella sp. after 24 h of incubation. The inhibition was mainly related to lactic acid production. This work demonstrated the possibility of using kefir grains to ferment an industrial by-product in order to obtain a natural acidic preparation with strong bacterial inhibitory properties that also contains potentially probiotic microorganisms.

Download Full-text