Lactic acid production from food waste using the lactogenic Escherichia coli strain JU15 : Optimization of reducing sugar recovery

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.

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Optimization of Lactic Acid Production from Food Waste by the Saccharification of Bacillus subtili

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.113-116.1080 ◽

2010 ◽

Vol 113-116 ◽

pp. 1080-1083 ◽

Cited By ~ 1

Author(s):

Ying Ying Liu ◽

Qun Hui Wang ◽

Li Wei Chen ◽

Xiao Qiang Wang ◽

Juan Wang

Keyword(s):

Bacillus Subtilis ◽

Lactic Acid ◽

Acid Concentration ◽

Food Waste ◽

Acid Production ◽

Lactic Acid Production ◽

Total Sugar ◽

Lactic Acid Concentration ◽

Two Phase ◽

Better Than

In order to reduce the costs of production and increase the lactic acid yields, this research adopts Bacillus subtilis to substitute enzymes. The method used in the study is two-phase fermentation - inoculate Bacillus subtilis to food waste to produce sugar, and then inoculate Lactobacillus to food waste to yield lactic acid. 87.22 g l–1 of total sugar can be obtained from non-autoclaved food waste in 30 h of saccharification at 40 centigrade. After two-phase fermentation, the optimal lactic acid concentration was 50.77g/L. The results indicate that two-phase fermentation is better than synchronous saccharification fermentation.

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

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.641-642.721 ◽

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.

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Correlation of Some Substrate Parameters in Growing Lactobacillus acidophilus on Vegetable and Fruit Cocktail Juices

Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca Agriculture ◽

10.15835/buasvmcn-agr:5119 ◽

2010 ◽

Vol 67 (2) ◽

Author(s):

Carmen Leane NICOLESCU ◽

Lavinia Claudia BURULEANU

Keyword(s):

Lactic Acid ◽

Lactobacillus Acidophilus ◽

Acid Production ◽

Sugar Content ◽

Lactic Acid Production ◽

Biomass Accumulation ◽

Reducing Sugar ◽

Fruit Juices ◽

Cell Multiplication ◽

Microbiological Methods

Using Lactobacillus acidophilus stains is a challenge in producing lactic acid fermented vegetable and fruit juices. There were analysed the correlation between the most important physico-chemical parameters of the substrate and the bacterial biomass accumulation in two vegetable and fruit juices. The data were collected during a 48 hour lactic acid fermentation using usually chemical and microbiological methods. There was analysed the correlation between the reducing sugar content and the lactic acid production, the correlation between the pH and lactic acid production, the correlation between the reducing sugar of the substrate and the microbial biomass accumulation and also between the lactic acid production and biomass accumulation. These correlations were analysed using simple regression on scatter plots. They were best fitted by the polynomial equation where the highest R2 were calculated. The two last correlations had large differences between the two experimental batches so that regression is not satisfactory to describe them. If all parameters were considered using the multiple regression, the correlation had a medium value because the cell multiplication of the bacteria Lactobacillus acidophilus in vegetable and fruit juices is influenced by many other environmental parameters. These had a large influence because juices are not the natural medium for this kind of lactic acid bacteria.

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