• 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.

• 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.

• 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.

• Asian-Australasian Journal of Animal Sciences
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• 제28권8호
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• pp.1123-1132
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• 2015

Winter wheat is a suitable crop to be ensiled for animal feed and China has the largest planting area of this crop in the world. During the ensiling process, lactic acid bacteria (LAB) play the most important role in the fermentation. We investigated the natural population of LAB in whole-crop wheat (WCW) and examined the quality of whole-crop wheat silage (WCWS) with and without LAB inoculants. Two Lactobacillus plantarum subsp. plantarum strains, Zhengzhou University 1 (ZZU 1) selected from corn and forage and grass 1 (FG 1) from a commercial inoculant, were used as additives. The silages inoculated with LAB strains (ZZU 1 and FG 1) were better preserved than the control, with lower pH values (3.5 and 3.6, respectively) (p<0.05) and higher contents of lactic acid (37.5 and 34.0 g/kg of fresh matter (FM), respectively) (p<0.05) than the control. Sixty LAB strains were isolated from fresh material and WCWS without any LAB inoculation. These LAB strains were divided into the following four genera and six species based on their phenotypic, biochemical and phylogenetic characteristics: Leuconostoc pseudomesenteroides, Leuconostoc citreum, Weissella cibaria, Lactococcus lactis subsp. lactis, Lactobacillus buchneri, and Lactobacillus plantarum subsp. plantarum. However, the prevalent LAB, which was predominantly heterofermentative (66.7%), consisted of Leuconostoc pseudomesenteroides, Leuconostoc citreum, Weissella cibaria, and Lactobacillus buchneri. This study revealed that most of isolated LAB strains from control WCWS were heterofermentative and could not grow well at low pH condition; the selective inoculants of Lactobacillus strains, especially ZZU 1, could improve WCWS quality significantly.

• 한국식품저장유통학회지
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• 제9권3호
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• pp.292-297
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• 2002

매실 추출물의 식품 보존제로서의 이용가능성을 검토하기 위하여 각각 0.5%, 1% 농도의 매실 추출물의 김치 유산균의 성장에 미치는 영향을 조사하고 1%, 3%의 매실 추출물을 김치에 첨가하여 숙성에 따른 이화학적, 미생물학적 변화를 관찰하였다. 매실 추출물의 농도가 높을수록 유산균의 성장을 억제하는 것으로 나타났으며 김치 숙성 중 pH, 산도, 총균수, 유산균수, 색상, 기호성을 대조구와 비교한 결과 매실 추출물 첨가구의 경우 pH 감소속도는 완만하였으며 산도 증가도 낮게 나타났다. 매실 첨가에 의한 김치 숙성 중 유산균수의 변화는 대조구보다 낮은 경향을 보였으나 숙성 25일째 유산균수가 6 log cycle 이상을 나타내어 숙성에 별다른 영향은 없을 것으로 사료되었다. 매실 추출물 1% 첨가구는 김치의 맛, 향, 색상에 영향을 거의 끼치지 않으면서 신맛을 억제시키는 효과가 뚜렷한 것으로 나타났다. 따라서, 매실 추출물을 사용하여 제조한 김치는 본래의 맛에 영향을 끼치지 않으면서 김치의 저장성을 연장시키고 또한 정장작용이 확인되고 있는 김치 유산균과 매실 내에 함유된 여러 가지 유기산을 함께 섭취할 수 있다는 점에서 김치의 품질을 한 단계 더 향상시킬 수 있을 것으로 사료된다.

• 미생물학회지
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• 제52권4호
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• pp.471-481
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• 2016

본 연구에서는 묵은지로부터 분리된 박테리오신을 생산하는 이상발효 유산균 및 내산성 효모가 사워도우의 저장 기간 연장과 품질 개선에 미치는 영향을 조사하였다. 유전자 염기서열 분석 결과 빵 부패세균인 Bacillus 속에 대한 항균활성을 나타낸 이상발효 유산균은 Leuconostoc mesenteroides LAS112, Lactobacillus brevis LAS129 및 L. mesenteroides subsp. dextranicum LAB137으로 동정되었고, 산성 pH 하에서 증식 가능한 효모는 Pichia membranifaciens YS05, Pichia fermentans YS19 및 Pichia anomala YS26으로 확인되었다. 사워도우 발효에 사용된 L. brevis LAS129는 L. mesenteroides LAS112 및 L. mesenteroides subsp. dextranicum LAS 137 보다 더많은 양의 초산과 박테리오신 활성을 나타내었으나, LAS112는 가장 많은 양의 유산을 생산하였다. Bacillus subtilis ATCC 35421에 대한 최대의 박테리오신 활성(640 AU/g)은 L. brevis LAS129와 P. membranifaciens YS05 혹은 P. anomala YS26으로 혼합 발효시킨 사워도우 내에서 관찰되었다. $30^{\circ}C$에서 24시간 발효 후 사워도우 내 LAS129의 균수($10^9CFU/g$)는 YS05 혹은 YS26의 효모 균수($10^7CFU/g$)보다 높게 검출되었다. 한편, 이들 균주들을 이용하여 발효시킨 사워도우 내에 존재하는 빵 부패균의 균수는 대조구 보다 유의하게(P < 0.05) 낮은 수준으로 나타났다.

• 한국식품영양과학회지
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• 제28권2호
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• pp.359-364
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• 1999

The studies were carried out to investigate antimicrobial activity of mixed extracts of Lithospermum erythrorhizon and Scutellaria baicalensis G. and crab shell against lactic acid bacteria isolated from kimchi. The effects of Lithospermum erythrorhizon and Scutellaria baicalensis G. extracts and crab shell on shelf life of kimchi were also investigated. The growth of heterofermentative and homofer mentative lactic acid bacteria was inhibited by 95% ethanol extracts of Lithospermum erythrorhizon and Scutellaria baicalensis G. The pH of kimchi containing 1% of mixed extracts Lithospermum erythrorhizon. and Scutellaria baicalensis G., and crab shell was lower than control during fermentation for 25 days of 10oC. The viable cells of the kimchi samples were lower than that of control during fermentation. The sensory qualities of the kimchi samples were a little inferior to the control during shelf life of kimchi.

• 한국식품과학회지
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• 제31권2호
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• pp.404-409
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• 1999

항균력을 나타낸 한약재 각각의 추출혼합물과 crab shell를 첨가하여 김치 숙성시와 동일한 조건에서 김치발효 관련 유산균의 증식 억제도를 검토한 결과 대조구에 비하여 약간 높은 억제도를 보였으며, 이를 김치 제조에 이용하여 숙성시키면서 김치의 이화학적, 미생물학적 변화를 검토한 결과 pH, 산도, 미생물 변화는 대조구에 비해 소목, 자초 추출혼합물과 crab shell 병용처리구가 낮은 경향을 보였다. 관능적인 면에서는 숙성이 진행됨에 따라 대조구에 비해 다소 낮은 경향으로 나타났다.

• Journal of Microbiology and Biotechnology
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• 제5권6호
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• pp.309-314
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• 1995

Samples were collected from a commercial ethanol production plant to enumerate the bacterial contamination in each step of a starch based ethanol production process. Though the slurry of raw material used in the process carried bacteria with various colony morphology in the order of $10^4$ per ml, only the colonies of white and circular form survived and propagated through the processes to the order of $10^8$ per ml at the end of fermentation. Almost all of the bacterial isolates from the fermentation broth were lactic acid bacteria. Heterofermentative Lactobacillus fermentum and L. salivarius, and a facultatively heterofermentative L. casei were major bacteria of an ethanol fermentation. In a batch fermentation L. fermentum was more detrimental than L. casei to ethanol fermentation. In a cell-recycled fermentation, ethanol productivity of 5.72 g $I^{-1} h^{-1}$ was obtained when the culture was contaminated by L. fermentum, whilst that of the pure culture was 9.00 g $1^{-1} h^{-1}$. Similar effects were observed in a cell-recycled ethanol fermentation inoculated by fermentation broth collected from an industrial plant, which showed a bacterial contamination at the level of 10$^8$ cells per ml.