• 한국초지조사료학회지
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• 제34권4호
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• pp.247-253
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• 2014

본 연구에서는 메타분석을 통하여 heterofermentative과 homofermentative LAB가 사일리지의 품질과 호기적 안정성에 대한 효과를 분석하였다. 일련의 분석결과 접종균으로 사용된 젖산균의 종류에 따라서 사일리지의 품질이 다르게 나타남을 확인할 수 있었다. 특히 호기적 안정성에 있어서 heterofermentative LAB의 사용이 매우 중요함을 알 수 있었다. 본 연구결과는 사일리지의 제조 목적 및 사용방법에 따라서 접종균주를 다르게 선발하여야 하며, 사용방법에 따라서 사일리지 내 유기산 조성을 변화시킬 수 있는 발효조건이 필요함을 시사하고 있고, 또한 보다 정밀한 사일리지 발효기술에 대한 기초자료를 제공한다.

• 한국미생물·생명공학회지
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• 제27권5호
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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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• 제17권4호
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• pp.333-338
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• 2002

생분해성 고분자 합성물질의 원료가 되는 젖산을 주로 생산하는 균을 김치로부터 분리하였다 SEM을 사용하여 관찰한 분리한 균의 형태는 연쇄간균이었고 165 rRNA sequencing 에 의해 계통발생학적 분석의 결과 Lactobacillus casei KH-1로 명명하였다. 1. casei KH-1는 g1ucose를 젖산으로 98%를 전환시키는 호모발효균이었으며, D(-)와 L(+)-이성질체를 각각 7%와 93%를 포함하는 racemic mixtrure로 젖산을 생산하였다. L. casei KH-1은 다른 lactobacillus속과는 달리 세포의 성장과 젖산의 생산에 기질로서 lactose를 이용하지 못하였지만 glucose의 이용은 이전의 연구들과 비교할 때 효과적이었다. Lactobacillus속의 배양에 사용되는 MRS배지의 질소원을 저렴한 원료 즉, YE와 CSL를 1:1로 첨가한 배지로 대신하여 최대의 젖산수율(1.09 mole .mole$^{-1}$)을 얻어 젖산발효에 효과적인 질소원의 대체가 이루어졌다

• 한국식품영양과학회지
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• 제26권3호
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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.

• 한국식품영양학회지
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• 제1권2호
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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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• 제21권1호
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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.

• 한국미생물·생명공학회지
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• 제36권3호
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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.

• 한국미생물·생명공학회지
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• 제25권1호
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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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• 제9권4호
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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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• 제9권4호
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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.