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

2012 ◽  
Vol 476-478 ◽  
pp. 2051-2054 ◽  
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.

Inhibitory Activity of Cheese Whey Fermented with Kefir Grains

2011 ◽  
Vol 74 (1) ◽  
pp. 94-100 ◽  
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.

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

2013 ◽  
Vol 641-642 ◽  
pp. 721-724
Author(s):  
Zhao Min Zheng ◽  
Tian Tian ◽  
Jin Hua Wang ◽  
Yong Ze Wang ◽  
Sheng De Zhou
Keyword(s):  
Escherichia Coli ◽  
Lactic Acid ◽  
Acid Production ◽  
Shake Flask ◽  
Lactic Acid Production ◽  
Lactate Production ◽  
Pyruvate Decarboxylase ◽  
Genetically Engineered ◽  
Acetate Production ◽  
A Minor

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.

scholarly journals Lactic acid production ability of Lactobacillus sp. from four tropical fruits using their by-products as carbon source

Heliyon ◽  
2021 ◽  
Vol 7 (5) ◽  
pp. e07079
Author(s):  
Joel Romial Ngouénam ◽  
Chancel Hector Momo Kenfack ◽  
Edith Marius Foko Kouam ◽  
Pierre Marie Kaktcham ◽  
Rukesh Maharjan ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Carbon Source ◽  
Acid Production ◽  
Lactic Acid Production ◽  
Tropical Fruits ◽  
By Products

scholarly journals Production of lactic acid by Enterococcus faecalis on waste glycerol from biodiesel production

2020 ◽  
Vol 26 (2) ◽  
pp. 151-156
Author(s):  
Jovan Ciric ◽  
Natasa Jokovic ◽  
Slavica Ilic ◽  
Sandra Konstantinovic ◽  
Dragisa Savic ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Carbon Source ◽  
Enterococcus Faecalis ◽  
Acid Production ◽  
Lactic Acid Production ◽  
Raw Material ◽  
Biodiesel Production ◽  
Waste Glycerol ◽  
Pure Glycerol ◽  
Microbial Utilization

Waste glycerol from biodiesel production is a valuable raw material that has been used to produce valuable microbial metabolites. In this work, the possibility of microbial utilization of waste glycerol obtained as a by-product in biodiesel production from sunflower and rapeseed oil by the lactic acid bacterium Enterococcus faecalis MK3-10A on a laboratory level was studied. For comparison, pure glycerol and glucose were used as carbon sources. The kinetics of the microbial biomass growth, the carbon source utilization, and the lactic acid production were monitored. The bacterium E. faecalis MK3-10A better grew in the media with glucose or pure glycerol as a carbon source, but the lactic acid production rate was the highest (14.6 mg/(ml/day)) in the medium with waste glycerol from the sunflower oil-based biodiesel production. Therefore, this waste glycerol might be a promising carbon source for lactic acidbacteria cultivation and lactic acid production.

scholarly journals Optimization of Lactic Acid Production from Pineapple By-Products and an Inexpensive Nitrogen Source Using Lactiplantibacillus plantarum strain 4O8

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Joel Romial Ngouénam ◽  
Pierre Marie Kaktcham ◽  
Chancel Hector Momo Kenfack ◽  
Edith Marius Foko Kouam ◽  
François Zambou Ngoufack
Keyword(s):  
Lactic Acid ◽  
Carbon Source ◽  
Nitrogen Source ◽  
Acid Production ◽  
Lactic Acid Production ◽  
Nitrogen Sources ◽  
Production Medium ◽  
Optimum Conditions ◽  
Pharmaceutical Industries ◽  
By Products

Lactic acid (LA) is used in food, cosmetic, chemical, and pharmaceutical industries and has recently attracted much attention in the production of biodegradable polymers. The expensive substances including carbon and nitrogen sources involved in its fermentative synthesis and the increasing market demand of LA have prompted scientists to look for inexpensive raw materials from which it can be produced. This research was aimed at determining the optimum conditions of lactic acid (LA) production from pineapple by-products and an inexpensive nitrogen source using Lactiplantibacillus plantarum strain 4O8. After collection and preparation of the carbon source (pineapple by-products) and nitrogen sources (by-products from fish, chicken, and beer brewing industries), they were used for the formulation of 4 different media in terms of nitrogen sources. Then, the proximate compositions of promising nitrogen sources were determined. This was followed by the screening of factors (temperature, carbon source, nitrogen source, MgSO4, MnSO4, FeSO4, KH2PO4, and KHPO4) influencing the production of LA using the definitive plan. Lastly, the optimization process was done using the central composite design. The highest LA productions ( 14.64 ± 0.05   g / l and 13.4 ± 0.02   g / l ) were obtained in production medium supplemented with chicken and fish by-products, respectively, making them the most promising sources of nitrogen. The proximate analysis of these nitrogen sources revealed that their protein contents were 83.00 ± 1.41 % DM and 74.00 ± 1.41 % DM for chicken by-products and fish by-products, respectively. Concerning the screening of factors, temperature, nitrogen source, and carbon source were the factors that showed a major impact on LA production in the production medium containing chicken by-products as nitrogen source. A pineapple by-product concentration of 141.75 g/l, a nitrogen source volume of 108.99 ml/l, and a temperature of 30.89°C were recorded as the optimum conditions for LA production. The optimization led to a 2.73-fold increase in LA production when compared with the production medium without nitrogen source. According to these results, chicken by-products are a promising and an inexpensive nitrogen source that can be an alternative to yeast extract in lactic acid production.

D-Lactic acid production from Cistus ladanifer residues: Co-fermentation of pentoses and hexoses by Escherichia coli JU15

2022 ◽  
Vol 177 ◽  
pp. 114519
Author(s):  
Júnia Alves-Ferreira ◽  
Florbela Carvalheiro ◽  
Luís C. Duarte ◽  
Ana R.P. Ferreira ◽  
Alfredo Martinez ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Lactic Acid ◽  
Acid Production ◽  
Lactic Acid Production ◽  
Cistus Ladanifer

Metabolic engineering of Pichia pastoris for L-lactic acid production using glycerin as carbon source

2015 ◽  
Author(s):  
Nadia Skorupa Parachin ◽  
Pollyne Lima ◽  
Nadielle Melo ◽  
Lucas Carvalho ◽  
Virgililio Castro ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Metabolic Engineering ◽  
Pichia Pastoris ◽  
Carbon Source ◽  
Acid Production ◽  
Lactic Acid Production
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