• Journal of The Korean Society of Grassland and Forage Science
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• v.34 no.4
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• pp.247-253
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• 2014

In the silage quality, the process of fermentation and use of micro-organism as starter cultures are crucial. The present study investigated the effect of homo and heterofermentative lactic acid bacteria as a starter culture strain on the silage quality and its aerobic stability using meta-analysis. Total 19 studies were used in the analysis. According to the strains of lactic acid bacteria used, experimental groups were assigned to heterofermentative (HEL), mixture of hetero and homofermentative (HHO), homofermentative (HOL) and various homofermentative (HOM). In each experimental group, standardized result of the treatment (with inoculant) was compared with the control (without inoculant) using risk ratio calculation method. The effect of experimental group was also compared. Different starter culture strains did not influence on silage pH and propionic acid production. However, lactic acid and acetic acid production were significantly (p<0.05) influenced by the start culture strains. HOM showed the greatest lactic acid production and HEL was the lowest. In contrast, HEL showed the greatest in acetic acid production and HOM and HOL were the lowest. In terms of ammonia nitrogen, HHO produced more (p<0.05) than the rest of the treatment. In crude protein and water soluble carbohydrate contents, there were no significant effects among treatments. Different strain of lactic acid bacteria significantly influenced on the effect of aerobic stability (p<0.05). Use of heterofermentative showed greater aerobic stability and the use of homofermentative lactic acid bacteria.

• Microbiology and Biotechnology Letters
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• v.27 no.5
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• pp.410-414
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• 1999

This study was carried out to investigate distribution of homofermentative lactic acid bacteria(LAB) and heterofermentative LAB during kimchi fermentation period. The number of heterofermentative LAB was decreased during the fermentation. The ethanol extracts of Lithospermum erythrorhizon and Sophrora flavescens AITON showed strong antimicrobial activities against both homofermentative LAB and heterofermentative LAB. The extracts of Glycyrrhiza uralensis and Curcuma longa showed stronger antimicrobial activity against hetrofermentative LAB than against homofermentative LAB. the antimicrobial activities of the plant extracts against LAB were accelerated by mixing of two or three kinds.

• KSBB Journal
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• v.17 no.4
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• pp.333-338
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• 2002

This study was targeted to isolate and characterize a bacterium producing lactic acid in a large amount. Lactic acid bacteria of about fifty strains were isolated from kimchi, a Korean traditional fermented vegetable food. Strain KH-1 of them was most effective in the lactic acid production and showed 99% homology with Lactobacillus casei from analysis of 16S rRNA sequencing. The conversion ratio of lactic acid from glucose by 1. casei KH-1 was 98% in anaerobic condition, and the lactic acid was composed as racemic mixture of D(-)-and L(+)-lactic acid, 7% and 93%, respectively. This result indicated that L. casei KH-1 was a homofermentative bacterium mainly producing L(+)-lactic acid. The strain KH-1 used glucose as a preferential substrate but not utilized lactose. In investigation of more inexpensive nitrogen source for cultivation of strain KH-1 using industrial MRS medium, when yeast extract and corn steep liquor were used at the ratio of 1 to 1, the molar yield of lactic acid produced per mole of glucose(Yp/s) was 1.09.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.3
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• pp.404-410
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• 1997

Amylase, protease, polygalacturonase and $\beta$-galactosidase activities were monitored during salting of Chinese cabbage and kimchi fermentation at 1$0^{\circ}C$. A part of enzymes in the tissue of Chinese cabbage were eluted during salting, and other remained enzymes activities were decreased in proportion to the amount of elution. But total enzyme activities were increased during salting. Amylase, protease and polygalacturonase activities decreased at the early fermentation stage but increased at the late fermentation stage. $\beta$-Galactosidase activity was continuously increased during all periods of fermentation. Enzymic actions at the early fermentation stage come from Chinese cabbge and at the late fermentation stage come from major microorganisms in kimchi fermentation. Kimchi fermentation involves the activation of the enzymes by salting; hydrolysis of micromoleculars such as polysaccarides cell wall composed polysaccarides and proteins of cell wall during early fermentation of kimchi; overripening of the kimchi caused by propagation of homofermentative lactic acid bacteria which demand autotroph.

• The Korean Journal of Food And Nutrition
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• v.1 no.2
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• pp.95-101
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• 1988

In order to produce lactic acid and calcium lactate very useful for foods and medical supplies, lactic acid fermentation was studied by Lactobacillus sporogenes, a spore forming lactic acid bacterium. When this bacterium was cultured aerobically in the spore forming medium, the spore forming rate was 96.0% as total cell number 20$\times$108/ml, spore number 19.2$\times$108/ml. One minute agitating every 1 hour in the flask culture, or agitation of 100rpm in the fermenter was most efficient to continue to ferment at 45$^{\circ}C$ for 4days in the fermentation medium containing 10% glucose as carbohydrate and CaCO3 as a neutralizing agent. This homofermentative lactic acid bacterium showed fermentation yield of 99.3% and more than 98.2% of the yield was L(+)-lactic acid.

• Journal of Microbiology and Biotechnology
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• v.21 no.1
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• pp.62-70
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• 2011

The antibacterial effects of nine lactic acid bacteria (LAB) against Campylobacter jejuni were investigated by using agar gel diffusion and co-culture assays. Some differences were recorded between the inhibition effects measured with these two methods. Only two LAB, Lb. pentosus CWBI B78 and E. faecium THT, exhibited a clear anti- Campylobacter activity in co-culture assay with dehydrated poultry excreta mixed with ground straw (DPE/GS) as the only growth substrate source. It was observed that the supplementation of such medium with a cellulase A complex (Beldem S.A.) enhanced the antimicrobial effect of both LAB strains. The co-culture medium acidification and the C. jejuni were positively correlated with the cellulase A concentration. The antibacterial effect was characterized by the lactic acid production from the homofermentative E. faecium THT and the lactic and acetic acids production from the heterofermentative Lb. pentosus CWBI B78. The antagonistic properties of LAB strains and enzyme combination could be used in strategies aiming at the reduction of Campylobacter prevalence in the poultry production chain and consequently the risk of human infection.

• Microbiology and Biotechnology Letters
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• v.36 no.3
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• pp.233-239
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• 2008

A new approach to the solubilization of excess activated sludge by the inoculation of lactic acid bacteria was studied to reduce the amount of sludge produced in the activated sludge treatment process. Aerobic microorganism in sludge was lysed in anaerobic condition and the cytoplasmic substance eluted was utilized as a carbon source by lactic acid bacteria. On the basis of sludge solubilization efficiency, Lactobacillus brevis and Leuconostoc mesenteroides subsp mesenteroides were selected the best candidates among five kinds of Lactobacillus sp. and seven kinds of Leuconostoc sp. The sludge solubilization efficiency by heterofermentative lactic acid bacteria was more efficient than that of homofermentative bacteria. Initial value of soluble COD (sCOD) was 1050 mg/L at the initial inoculation time increased to 3070 mg/L (192% solubilization) at 96 h of the incubation time. The inoculation of lactobacillus brevis to the sludge resulted in 2824% increase in sCOD value after 96 h of incubation than the control experiment. Leuconostoc mesenteroides subsp mesenteroides showed 152% increase of solubilization and 30% increase of S-COD/T-COD on 96 h of incubation time. Considering the increase of S-COD by the inoculation of Leuconostoc sp. on 24 h, 10% inoculation of lactic acid bacteria to the sludge was most effective.

• Microbiology and Biotechnology Letters
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• v.25 no.1
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• pp.96-101
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• 1997

Among the lactic flora responsible for the development of acidity and characteristic flavor of Kimchi which is a traditional fermented Chiness cabbage. Homofermentative Lactobacillus plantarum is rod-shaped and to be known to ewert major role during later fermentation period. Once this strain establishes main flaora in the Kimchi fermentation process, it gives rise to excess acid production to reduce the taste and quality of Kimchi during storage. As a primary work to increase the keeping quality using virulent Lactobaillus plantarum bacteriophages, it was isolated sucessfully from collected Kimchi samples and their characteristics were studied. The new isolated phage, named SC 921, adsorbed to its host without Ca$^{2+}$, and nearly eliminated at 60$\circ $C of heat treatment for 5 min. This phages were atable at pH 4~ 10 but inactivated below pH 3.0 or pH 11.0 above. The latent period, rise period, and burst size of this phage was 100 min, 120 min, 31$\pm $2pfu/ml, respectively. Electron micrograph showed the phages particles were unusually oval feature of head (dia 80~ 120 nm) without contractile tail.

• Biotechnology and Bioprocess Engineering:BBE
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• v.9 no.4
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• pp.303-308
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• 2004

We isolated a novel lactic acid bacterium from a Korean traditional fermented food, soybean paste. The newly isolated strain, dubbed RKY2, grew well on glucose, sucrose, galactose, and fructose, but it could not utilize xylose, starch, or glycerol. When the partially amplified 16S rDNA sequence (772 bp) of the strain RKY2 was compared with 10 reference strains, it was found to be most similar to Lactobacillus pentosus JCM $1588^T$, with 99.74% similarity. There-fore, the strain RKY2 was renamed Lactobacillus sp. RKY2, which has been deposited in the Korean Collection for Type Cultures as KCTC 10353BP. Lactobacillus sp. RKY2 was found to be a homofermentative lactic acid bacterium, because its end-product from glucose metabolism was found to be mainly lactic acid. It could produce more than 90 g/L of lactic acid from MRS medium supplemented with 100 g/L of glucose, with 5.2 g $L^-1$ $h^-1$ of productivity and 0.95 g/g of lactic acid yield.

• Biotechnology and Bioprocess Engineering:BBE
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• v.9 no.4
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• pp.318-322
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• 2004

Lactic acid is an environmentally benign organic acid that could be used as a raw material for biodegradable plastics if it can be inexpensively produced by fermentation. Two genes (ldhL and ldhD) encoding the L-(+) and D-(-) lactate dehydrogenases (L-LDH and D-LDH) were cloned from Lactobacillus sp., RKY2, which is a lactic acid hyper-producing bacterium isolated from Kimchi. Open reading frames of ldhL for and ldhD for the L and D-LDH genes were 962 and 998 bp, respectively. Both the L(+)- and D(-)-LDH proteins showed the highest degree of homology with the L- and D-lactate dehydrogenase genes of Lactobacillus plantarum. The conserved residues in the catalytic activity and substrate binding of both LDHs were identified in both enzymes.