• 한국식품영양학회지
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• 제17권1호
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• pp.72-79
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• 2004

멸치젓갈로부터 ν-aminobutyric acid(GABA)을 생성하는 유산균주를 분리 동정하였다. 멸치젓갈로부터 분리한 9종의 유산균 중 GABA 생산능이 우수한 균주를 순수 분리하여 형태학적 특성과 gram positive identification(GPI) card 와 API 50kit로 동정한 결과 Lactobacillus brevis BH-21, Lactobacillus rhamnosus BH-28 및 Lactobacillus plantarum BH-38로 동정하였다. 이들 Lactobacillus 속 균주중 Lactobacillus brevis BH-21이 GABA생성능력이 제일 우수하였고, GABA 생성함량은 배지(0.1% glucose, 0.1% yeast extracts, 0.05% polypeptone, 0.002 % MgSO$_4$$.$4$H_2O$, 0.001% FeSO$_4$$.$7$H_2O$, 0.01% NaCl, 0.1% monosodium glutamate, pH 6.0)에서 Lactobacillus brevis BH-21을 배양하였을 때, 배양 24시간에 43.2mg/mL의 GABA을 생성하였다.

• 한국응용과학기술학회지
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• 제39권4호
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• pp.517-526
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• 2022

본 연구의 목적은 효소 가수분해 및 유산균 혼합발효기술을 이용하여 GABA 함량이 강화된 발효 다시마 추출물을 생산함에 있다. TLC 분석방법을 통해 GABA 생성능력이 우수한 균주 L. plantarum KCTC 21004, L. acidophilus KCTC 3164, L. sakei subsp. sakei KCTC 3598를 선정하였다. 선정된 균주를 이용한 유산균 발효의 특성은 배양 시간이 증가 할수록 적정 산도는 증가하였고 pH는 감소하는 경향을 나타내었다. GABA 생성능력이 우수한 3종의 균주 중 L. plantarum KCTC 21004이 GABA 함량이 136.4 mg/100g으로 우수하였다. 이러한 연구 결과는 유산균을 이용한 GABA 생산과정에 있어서 기초적인 자료로 제공될 것으로 판단된다.

• Animal Bioscience
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• 제35권9호
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• pp.1379-1389
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• 2022

Objective: This study identified the major lactic acid bacteria (LAB) strains from different fermented total mixed rations (FTMRs) via metataxonomic analysis and evaluated the ability of their standard strain as ensiling inoculants for corn stover silage. Methods: The bacterial composition of eight FTMRs were analyzed by 16S rDNA sequencing. Corn stover was ensiled without LAB inoculation (control) or with 1×10⁶ cfu/g LAB standard strain (Lactobacillus vaginalis, Lactobacillus reuteri, Lactobacillus helveticus, or Lactobacillus paralimentarius) selected from the FTMRs or 10 g/t commercial silage inoculant (CSI) around 25℃ for 56 days. For each inoculation, a portion of the silage was sampled to analyze ensiling characteristics at time intervals of 0, 1, 3, 7, 14, 28, and 56 days, gas production (GP), microbial crude protein and volatile fatty acids as the measurements of rumen fermentation characteristics were evaluated in vitro with the silages of 56 days after 72 h incubation. Results: Lactobacillus covered >85% relative abundance of all FTMRs, in which L. pontis, L. vaginalis, L. reuteri, L. helveticus, and L. paralimentarius showed >4% in specific FTMRs. CSI, L. helveticus, and L. paralimentarius accelerated the decline of silage pH. Silage inoculated with L. paralimentarius and CSI produced more lactic acid the early 14 days. Silage inoculated with L. paralimentarius produced less acetic acid and butyric acid. For the in vitro rumen fermentation, silage inoculated with CSI produced more potential GP, isobutyric acid, and isovaleric acid; silage inoculated with L. helveticus produced more potential GP and isovaleric acid, silage inoculated with L. paralimentarius or L. reuteri produced more potential GP only. Conclusion: The standard strain L. paralimentarius (DSM 13238) is a promising ensiling inoculant for corn stover silage. The findings provide clues on strategies to select LAB to improve the quality of silage.

• 한국버섯학회지
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• 제11권4호
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• pp.187-193
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• 2013

A galactose fermentation bacterium producing lactose from red seaweed, which was known well to compromise the galactose as main reducing sugar, was isolated from button mushroom bed in Buyeo-Gun, Chungchugnamdo province. The lactic acid bacteria MONGB-2 was identified as Lactobacillus paracasei subsp. tolerans by analysis of 16S rRNA gene sequence. When the production of lactic acid and acetic acid by L. paracasei MONGB-2 was investigated by HPLC analysis with various carbohydrates, the strain MONGB-2 efficiently convert the glucose and galactose to lactic acid with the yield of 18.86 g/L and 18.23 g/L, respectively and the ratio of lactic acid to total organic acids was 1.0 and 0.91 g/g for both substrates. However, in the case of acetic acid fermentation, other carbohydrates besides galactose and red seaweed hydrolysate could not be totally utilized as carbon sources for acetic acid production by the strain. The lactic acid production from glucose and galactose in the fermentation time courses was gradually enhanced upto 60 h fermentation and the maximal concentration reached to be 16-18 g/L from both substrates after 48 h of fermentation. The initial concentration of glucose and galactose were completely consumed within 36 h of fermentation, of which the growth of cell also was maximum level. In addition, the bioconversion of lactic acid from the red seaweed hydrolysate by L. paracasei MONGB-2 appeared to be about 20% levels of the initial substrates concentration and this results were entirely lower than those of galactose and glucose showed about 60% of conversion. The apparent results showed that L. paracasei MONGB-2 could produce the lactic acid with glucose as well as galactose by the homofermentation through EMP pathway.

• 한국미생물·생명공학회지
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• 제24권3호
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• pp.357-363
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• 1996

For the production of D-lactic acid from DL-2-chloropropionic acid, about 80 strains of bacteria capable of assimilating DL-2-chloropropionic acid as a sole carbon and energy source were isolated from the soil. JH-007 strain that showed the higest productivity of D-lactic acid and didn't produce L-lactic acid from DL-2-chloropropionic acid was selected from them and identified as Pseudomonas sp. The optimal conditions for the production of D-lactic acid from DL-2-chloropropionic acid were examined. The resting cells of JH-007 cultured in LB medium containing 3 g/l of DL-2-chloropropionic acid were used as an enzyme source. The reaction mixtures for the maximal production of D-lactic acid were consist of 10 g/l of resting cells and 3 g/l of DL-2-chloropropionic acid in 125 mM sodium carbonate buffer. The optimal pH for the reaction was 10.0 and the optimal temperature was 30$\circ$C. When 1 g/l of DL-2-chloropropionic acid was added intermittently to the reaction mixture under the above condition, 5.72 g/l of D-lactic acid was produced after incubation of 5 hrs. This amount of D-lactic acid corresponded to a 98.4% yields and the optical purity was 99.8%.

• Asian-Australasian Journal of Animal Sciences
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• 제16권11호
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• pp.1680-1685
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• 2003

Antimutagenicity of milk cultured with lactic acid bacteria isolated from dadih on the mutagenicity of heated salty and sweet tauco was examined using streptomycin dependent (SD) 510 strain of Salmonella typhimurium TA 98 as a tester culture. Cultured milk samples exhibited widely antimutagenic activity against mutagenic heated salty and sweet tauco. Lc. lactis subsp. lactis R-22, Lc. lactis subsp. casei R-35, Lc. lactis subsp. casei R-52 and E. faecalis subsp. liquefaciens R-55 exhibited no inhibitory effect on the mutagenic heated salty tauco. Mutagenicity of heated sweet tauco was inhibited by cultured milks stronger than that of heated salty tauco. Milk cultured with Lc. lactis subsp. cremoris R-48, Leuc. mesentroides R-51 and Lc. lactis subsp. casei R-68 showed high inhibition against the mutagenicity of both heated salty and sweet taucos. Antimutagenic activity of the cultured milks against mutagenic heated tauco was attributed to the bacterial cells. Among the three strains which showed high antimutagenicity, only Leuc. mesentroides R-51 was tolerant to both acid and bile; so this strain can be used as probiotic in preventing the occurrence of mutagenesis caused by mutagenic heated food like tauco.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.623-625
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• 2000

Bacteriocin을 생산하는 유산균을 김치에서 분리하였고 Lactococcus latis subsp. lactis로 확인 되었으며 bacteriocin의 최대생산조건은 $30^{\circ}C$, 6시간으로 다양한 유산균 및 Pseudomonas synsantha, Acetobacter aceti의 생육을 저해하였고 여러 peptidases에 의해 불활성화되었다. 또한 다양한 범위의 pH와 열처리에 안정하였고 SDS-PAGE결과 약 8 Kda으로 확인되었다.

• 한국미생물·생명공학회지
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• 제44권2호
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• pp.163-170
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• 2016

전국 각지에서 수집된 발표식품으로부터 젖산균을 분리하고 유해균인 B. cereus, L. monocytogenes, S. Typhimurium, S. aureus 및 S. epidermidis 균주에 대하여 생육 억제효능이 강한 L2167 균주를 선발하고, 16S rDNA 분석법을 이용하여 L. plantarum로 동정하였다. L2167 균주의 단백질 분획물을 제작하여 S. aureus 등 5종의 유해균 배양액에 첨가한 후, 전자현미경으로 관찰하였다. L. plantarum L2167 균주의 균체 단백질 분획물은 유해균의 생육을 억제하였으며, 생육 억제활성은 균체 내부에 함유된 단백질이 유해균의 세포막을 파괴하는 것에서 기인하는 것으로 추정되었다. L. plantarum L2167은 pH 5.5로 조절한 MRS 배지에서 35℃로 배양하였을 때, 가장 우수한 비성장속도를 나타냈으며, 대조구로 사용된 L. plantarum KCTC21004보다 NaCl에 대하여 민감한 특징을 나타내었다. 본 연구를 통하여 선발한 L. plantarum L2167 균주는 추가연구를 통하여 유해균의 생육을 효율적으로 억제할 수 있는 스타터 균주로서 개발될 수 있을 것으로 기대된다.

• 미생물학회지
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• 제50권3호
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• pp.233-238
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• 2014

전통주 양조에 적합한 종균 선발의 일환으로 에탄올 저항성 및 산 생성능이 낮은 한 유산균주를 전통 메주에서 분리하였고, 생화학적 동정 및 16S rRNA 유전자 염기 서열의 분석 결과 유산균인 Lactobacillus brevis로 동정되었다. 8% (v/v) 에탄올을 농도 별로 첨가한 MRS 배지에 이 균주를 $30^{\circ}C$. 96시간 배양한 결과 잘 생육하였으며, 배양 후 최종 pH는 4.5까지 감소하였다. 이 균주는 또한 식품 부패 및 병원성 균들인 Escherichia coli, Bacillus cereus, Listeria monocytogenes, Stapylococcus aureus, Micrococcus luteus, Pseudomonas aeruginosa에 대해 증식 억제능을 나타냈다. 이 결과들로부터 L. brevis JBE 30은 전통주 양조에 적합한 종균으로 사용 될 수 있음을 보였다.

• Preventive Nutrition and Food Science
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• 제6권3호
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• pp.192-196
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• 2001

Ethanol extracts from 36 vegetable samples were assayed for their growth-promoting effects on Bifidobacterium bifidum, B. longum, and Lactobacillus casei The growth-promoting effects varied according to bacterial strain and vegetable species. In modified Gy rgy broth, extracts of Lactuca sativa, Lycopersicon esculentum and L escutentum var. cerasiforme exhibited strong growth-promoting responses toward B. longum, and significant and strong growth- promoting response toward B. bifidum was observed in extracts of Actinidia arguta, Allium cepa, A. sativum, Brassica campestris subsp. napus vats. pekinensis, Capsicum frutescens, Daucus carota var. sativa, L sativa, 1. esculentum and L. esculentum var. cerasforme, Nelumbo nucifera, Cucurbita moschata, Lackca sativa var. capitata, and Rubus coreanus. For L casei, extracts of A. fshlosum, A. hberosum, Cichorium intbus, Cucurbita moschat\ulcorner Ipomoea batatas, 1. sativa var. capitata, L. esculentum, P. brachycarpa, Raphanus sativus, R. coreanus, and S. melongena strongly enhanced the growth of this bacteria. In modified Gy rgy broth, the promoting effect was most pronounced with B. bifidum and L. casei among lactic acid bacteria used. In MRS broth, A. arguta, A. cepa, A. sativum, B. campestris subsp. napus var. pekinensis, C. frutescens, and D. carota var. sativa L. satiw var. capitata, and R. coreanus strongly enhanced the growth of B. bifidum, Growth of B. longum was strongly affected by the addition of extracts from L. sativa var. capitata. For L casei, moderate growth-promoting responses were observed in 9 vegetable extracts. The promoting effect in MRS broth was most pronounced with B. bifidum among lactic acid bacteria used.