• 한국식품과학회지
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• 제34권1호
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• pp.73-78
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• 2002

본 연구에서는 식품용 프로바이토틱 생균인 비스루트균의 인공위액과 인공담즙산에 대한 내성, 효소활성, 항생물질과 알콜에 대한 내성, 그리고 병원성 세균에 대한 항균기작 등 주요 생균제 특성에 대하여 검토하였다. 인공위액 내성 실험에서는 pH 2.5로 조성된 인공위액을 통과한 생존율이 매우 높았으며 균수가 $2.4{\times}10^7\;CFU/mL$의 수준이었다. 인공담즙산에 대한 내성에서는 pH 2.5의 인공위액을 통과한 비스루트균의 인공담즙산의 내성은 oxgall이 함유되지 않은 대조구$(1.6{\times}10^7\;CFU/mL)$에 비해 오히려 균수가 증가되었으며, 최종적인 생존수가 $3.3{\times}10^7\;CFU/mL$ 으로 확인됨으로써 프로바이오틱 생균으로 매우 우수한 특성을 가지고 있었다. 효소활성을 측정한 결과, 비스루트균은 발암효소인 ${\beta}-glucuronidase$ 및 ${\beta}-glucosidase$ 의 활성이 나타나지 않았다. 또한 항생물질에 대한 내성은 rifamycin $10\;{\mu}g/mL$ 이상의 농도에 대해서는 생육 저해를 보였으나, $nisin(100\;{\mu}g/mL)$, $streptomycin(20\;{\mu}g/mL)$, $tetracycline(20\;{\mu}g/mL)$에 대해 내성을 보였다. 그리고 비스루트균의 알콜에 대한 내성은 4%의 농도에서 저해를 받았으며, 8%의 농도에서 더욱 저해를 받으나, $8{\sim}32%$ 범위의 농도에서는 균수가 더욱 크게 감소를 하지는 않았다. Listeria에 대한 향균기작을 측정한 결과, 24시간이내에 L. monocytogenes ATCC 19111을 완전히 저해를 하였으며, bactericidal한 양상을 나타내었다. 본 연구를 통해 밝혀진 비스루트균의 프로바이오틱 특성은 기능성 식품의 개발 등 산업적으로 매우 유용하다고 판단된다.

• Asian-Australasian Journal of Animal Sciences
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• 제18권8호
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• pp.1199-1208
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• 2005

Abatement of greenhouse gas emitted from ruminants and promotion of biogas energy from animal effluent were comprehensively examined in each anaerobic fermentation reactor and animal experiments. Moreover, the energy conversion efficiency of biomass energy to power generation were evaluated with a gas engine generator or proton exchange membrane fuel cell (PEMFC). To mitigate safely rumen methanogenesis with nutritional manipulation the suppressing effects of some strains of lactic acid bacteria and yeast, bacteriocin, $\beta$1-4 galactooligosaccharide, plant extracts (Yucca schidigera and Quillaja saponarea), L-cysteine and/or nitrate on rumen methane emission were compared with antibiotics. For in vitro trials, cumulative methane production was evaluated using the continuous fermented gas qualification system inoculated with the strained rumen fluid from rumen fistulated Holstein cows. For in vivo, four sequential ventilated head cages equipped with a fully automated gas analyzing system were used to examine the manipulating effects of $\beta$1-4 galactooligosaccharide, lactic acid bacteria (Leuconostoc mesenteroides subsp. mesenteroides), yeast (Trichosporon serticeum), nisin and Yucca schidigera and/or nitrate on rumen methanogenesis. Furthermore, biogas energy recycled from animal effluent was evaluated with anaerobic bioreactors. Utilization of recycled energy as fuel for a co-generator and fuel cell was tested in the thermophilic biogas plant system. From the results of in vitro and in vivo trials, nitrate was shown to be a strong methane suppressor, although nitrate per se is hazardous. L-cysteine could remove this risk. $\beta$1-4 galactooligosaccharide, Candida kefyr, nisin, Yucca schidigera and Quillaja saponarea are thought to possibly control methanogenesis in the rumen. It is possible to simulate the available energy recycled through animal effluent from feed energy resources by making total energy balance sheets of the process from feed energy to recycled energy.

• 한국식품과학회지
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• 제34권3호
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• pp.536-539
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• 2002

본 연구에서는 증자 콩에 증식하여 부패취를 유발하는 오염균인 야생고초균의 생육을 억제하고 정상발효를 유도하기위해 젖산, 과산화수소 등과 항균성 물질인 bacteriocin을 생성하는 유산균으로 1단 발효를 실시한 후 장류용 황국균을 접종하여 2단 발효 후 다시 고초균으로 3단 발효시켜 황국균과 고초균의 protease, peptidase를 효과적으로 사용함으로서 단백질 분해율이 높아 아미노산 생성량이 많은 기호성 높은 고품질의 메주를 제조하였다. 3단 발효법으로 제조된 메주의 수분함량과 pH를 측정한 결과 각각 54.0 %와 pH 7.0였고 제조된 메주를 30일간 20% 염수로 용출하여 총 유리 아미노산함량을 비교한 결과 3단 발효법으로 제조된 메주구가 대조구에 비해 약 $3{\sim}5$배 높게 나타났다. 특히 장류의 맛을 좌우하는 감칠 맛 성분인 glutamic acid와 aspartic acid의 함량은 대조구에 비해 매우 높아 메주를 원료로 제조하는 장류의 품질을 향상시킬 수 있으며 유리아미노산이 용출되는 시간이 대조구보다 짧아 장류 제조시 발효기간을 1/3정도로 단축시킬 수 있다.

• 생명과학회지
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• 제33권1호
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• pp.91-101
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• 2023

박테리오신은 리보솜에서 합성된 항균 펩타이드로, 박테리아에 의해 생성되어 유사하거나 밀접한 관련이 있는 박테리아 균주의 성장을 억제한다. 니신이 처음 발견된 이래로, 독특한 구조와 다양한 항균활성 방식을 가진 많은 박테리오신들이 기술되었고, 생산, 분비, 면역을 암호화하는 유전자들이 보고되었다. 니신은 치즈와 액체 달걀, 소스, 통조림 식품에 적용되는 박테리오신 중 하나이다. 많은 Bacillus 속 박테리오신들은 변역 후 변형된 펩타이드인 란티바이오틱스에 속한다. 다른 속의 Bacillus는 또한 많은 다른 비-란티바이오틱스 박테리오신을 생산한다. Bacillus 속 박테리오신은 때때로 더 넓은 항균 스펙트럼 때문에 더욱 중요해지고 있다. 박테리오신은 식품 및 제약 산업에서 식품 부패 및 병원성 세균 증식을 방지하기 위한 매력적인 화합물로 간주된다.박테리오신은 식품계에서 다양한 방식으로 생물학적 방부제로 사용될 수 있다. 생물 보존은 미생물 및/또는 그 대사산물을 사용하는 식품의 유통기한 연장 및 안전성 향상을 의미한다. 새로운 항균 화합물에 대한 수요는 식품 미생물학적 안전성을 향상시킬 수 있는 새로운 기술에 대한 큰 관심을 가져왔다. 박테리오신의 응용은 식품에서 인간의 건강으로 확대되고 있다. 오늘날 많은 연구자들은 박테리오신에 대한 관심을 식품보존에서 감염과 항생제 내성 질병을 유발하는 박테리아의 처리로 전환하고 있는 추세이다. 박테리오신 연구의 이 흥미로운 새로운 시대는 의심할 여지없이 새로운 발명과 새로운 응용으로 이어질 것이다. 이 리뷰에서 우리는 Bacillus 속에 의해 생산되는 박테리오신의 다양한 특성과 응용을 요약한다.

• Journal of Microbiology and Biotechnology
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• 제12권1호
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• pp.96-105
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• 2002

A bacteriocin-producing strain identified as Pediococcus acidilactici was isolated from kimchi. The bacteriocin was identified to belong to the pediocin family and exhibited bactericidal activity against most Gram-positive bacteria as well as some Gram-negative bacteria. The bacteriocin was stable up to $80^{\circ}C with wide pH ranges (5.0-10.0). The bactericidal activity remained unchanged after treatment with nonproteolytic enzymes such as nuclease and ${\alpha}$-amylase, however, it was destroyed after treatment with protease. The bacteriocin was effectively extracted by the pH-mediated adsorption-desorption method and purified effectively by semi-preparative RP-HPLC. The molecular weight of the bacteriocin was 4,622, as determined by electrospray mass spectrometry. The amino acid sequence consisted of 44 amino acid residues with four cysteines. The high solubility and pH stability of the isolated pediocin provide definite advantages over nisin and other bacteriocins in regards to its potential applications.

• Asian-Australasian Journal of Animal Sciences
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• 제23권6호
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• pp.700-707
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• 2010

Effects of protease-resistant antimicrobial substances (PRA) produced by Lactobacillus plantarum and Leuconostoc citreum on rumen methanogenesis were examined using the in vitro continuous methane quantification system. Four different strains of lactic acid bacteria, i) Lactococcus lactis ATCC19435 (Control, non-antibacterial substances), ii) Lactococcus lactis NCIMB702054 (Nisin-Z), iii) Lactobacillus plantarum TUA1490L (PRA-1), and iv) Leuconostoc citreum JCM9698 (PRA-2) were individually cultured in GYEKP medium. An 80 ml aliquot of each supernatant was inoculated into phosphate-buffered rumen fluid. PRA-1 remarkably decreased cumulative methane production, though propionate, butyrate and ammonia N decreased. For PRA-2, there were no effects on $CH_4$ and $CO_2$ production and fermentation characteristics in mixed rumen cultures. The results suggested that PRA-1 reduced the number of methanogens or inhibited utilization of hydrogen in rumen fermentation.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2004년도 춘계학술대회
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• pp.303-306
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• 2004

참멍게의 체액세포로부터 산추출 후, 조 추출물에서 천연항균소재를 개발하기 위해 먼저 멍게 조 추출액을 직접 Tricine-SDS PAGE를 통하여 주요 펩타이드들의 분자량의 범위를 살펴본 결과 6kDa 이하의 분자량의 펩타이드들이 다량 존재함을 알수 있었다. 펩타이드들의 size별 항균활성을 알아보기 위해 여러 사이즈의(100, 50, 30, 10 kDa)의 한외여과만으로 여과하여 그 여과액들의 specific 활성을 알아본 결과 여과막의 cut-off size에 상관없이 거의 인정한 specific activity를 가짐을 알 수 있었다. 멍게 조 추출액의 여러 미생물에 대한 항균 스펙트럼을 알아보기 위해 E.coli, P. aeruginosa, S. typhi, V. parahaemolyticus, L. monocytogenes, B. sutillus, S. aureus, S. mutans 균주들을 $10^5 CFU/ml$로 부터 4log 감소시키는 농도를 측정한 결과 각각 200, 50, 60, 10, 25, 30, 100, 100ppm 농도였으며, 대표적 상용화 항균 펩타이드인 Nisin과의 항균활성 비교 결과 비슷하거나 월등히 뛰어난 결과를 보여주었다. 또한 추출액의 열안정성을 측정하기 위해 $100^{\circ}C$에서 10분간 가열한 후 원액과의 항균력의 차이를 Radial diffusion assay로 알아본 결과 항균력의 차이가 거의 없음을 알 수 있었다.

• Food Science and Biotechnology
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• 제15권5호
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• pp.677-682
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• 2006

Strain HY701 was isolated from human feces for probiotic use by selecting highly resistant isolates to artificial gastric acid and bile acid. Strain HY701 was identified as Lactobacillus reuteri using 16S rDNA sequencing, and tentatively named L. reuteri HY701. The resistance of L. reuteri HY701 to artificial gastric acid (PH 2.5) was high with a survival rate of over 90%. L. reuteri HY701 also showed high tolerance to artificial bile acid after incubation in artificial gastric acid. Using the API ZYM test kit, the carcinogenic enzymes (${\beta}$-glucuronidase and (${\beta}$-glucosidase were not detected with L. reuteri HY70l, while the beneficial enzyme (${\beta}$-galactosidase was weakly detected. L. reuteri HY701 was sensitive to $100\;{\mu}g/mL$ nisin, $20\;{\mu}g/mL$ roxithromycin, $15\;{\mu}g/mL$ erythromycin, but resistant to $20\;{\mu}g/mL$ streptomycin, $10\;{\mu}g/mL$ tetracycline, $20\;{\mu}g/mL$ ciprofloxacin, $20\;{\mu}g/mL$ nystatin, $20\;{\mu}g/mL$ gentamycin, $10\;{\mu}g/mL$ doxycycline, $10\;{\mu}g/mL$ chloramphenicol, and $20\;{\mu}g/mL$ ampicillin. L. reuteri HY701 was shown to possess bactericidal activity as it inhibited the growth of Listeria monocytogenes ATCC 19111 and Escherichia coli JM109 completely within 24 hr of incubation. These results indicate that L. reuteri HY701 could be used as a probiotic strain.

• 한국미생물·생명공학회지
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• 제29권1호
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• pp.1-11
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• 2001

Lactic acid bacteria (LAB) are widely used for various food fermentation. With the recent advances in modern biotechnology, a variety of bio-products with the high economic values have been produced using microorganisms. For molecular cloning and expression studies on the gene of interest, E. coli has been widely used mainly because vector systems are fully developed. Most plasmid vectors currently used for E, coli carry antibiotic-resistant markers. As it is generally believed that the antibiotic resistance markers are potentially transferred to other bacteria, application of the plasmid vectors carrying antibiotic resistance genes as selection markers should be avoided, especially for human consump-tion. By contrast, as LAB have some desirable traits such that the they are GRAS(generally recognized as safe), able to secrete gene products out of cell, and their low protease activities, they are regarded as an ideal organism for the genetic manipulation, including cloning and expression of homologous and heterologous genes. However, the vec-tor systems established for LAB are stil insufficient to over-produce gene products, stably, limiting the use of these organisms for industrial applications. For a past decade, the two popular plasmid vectors, pAM$\beta$1 of Streptococcus faecalis and pGK12 theB. subtilis-E. coli shuttle vector derived from pWV01 of Lactococcus lactis ssp. cremoris wg 2, were most widely used to construct efficient chimeric vectors to be stably maintained in many industrial strains of LAB. Currently, non-antibiotic markers such as nisin resistance($Nis^{r}$ ) are explored for selecting recombi-nant clone. In addition, a gene encoding S-layer protein, slp/A, on bacterial cell wall was successfully recombined with the proper LAB vectors LAB vectors for excretion of the heterologous gene product from LAB Many food-grade host vec-tor systems were successfully developed, which allowed stable integration of multiple plasmid copies in the vec-mosome of LAB. More recently, an integration vector system based on the site-specific integration apparatus of temperate lactococcal bacteriophage, containing the integrase gene(int) and phage attachment site(attP), was pub-lished. In conclusion, when various vector system, which are maintain stably and expressed strongly in LAB, are developed, lost of such food products as enzymes, pharmaceuticals, bioactive food ingredients for human consump-tion would be produced at a full scale in LAB.

• Journal of Microbiology and Biotechnology
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• 제16권11호
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• pp.1799-1808
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• 2006

A food-grade integration vector based on site-specific recombination was constructed. The 5.7-kb vector, pIMA20, contained an integrase gene and a phage attachment site originating from bacteriophage A2, with the ${\alpha}$-galactosidase gene from Lactobacillus plantarum KCTC 3104 as a selection marker. pIMA20 was also equipped with a controllable promoter of nisA ($P_{nisA}$) and a signal peptide-encoding sequence of usp45 ($SP_{usp45}$) for the production and secretion of foreign proteins. pIMA20 and its derivatives mediated site-specific integration into the attB-like site on the Lactococcus lactis NZ9800 chromosome. The vector-integrated recombinant lactococci were easily detected by the appearance of blue colonies on a medium containing $X-{\alpha}-gal$ and also by their ability to grow on a medium containing melibiose as the sole carbon source. Recombinant lactococci maintained these traits in the absence of selection pressure during 100 generations. The ${\alpha}-amylase$ gene from Bacillus licheniformis, lacking a signal peptide-encoding. sequence, was inserted downstream of $P_{nisA}\;and\;SP_{usp45}$ in pIMA20, and the plasmid was integrated into the L. lactis chromosome. ${\alpha}-Amylase$ was successfully produced and secreted by the recombinant L. lactis, controlled by the addition and concentration of nisin.