• Journal of Microbiology and Biotechnology
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• 제10권2호
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• pp.147-153
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• 2000

This study was conducted to compare probiotic activities and physiological functions of Bifidobacterium longum Mk-G7 with weveral commercial and type strains of bifidobacteria. bif. longum MK-G7 showed the highest acid tolerance against HCl and acetic acid, whereas bif. infantis Y-1 showed the lowest acid tolerance and more than 4 log cycles of viable cell count decreased due to acid injuty. Viable cell counts of bifidobacteria strains decreased more than 1.5 log cycles owing to oxygen toxicity, with the exception of Bif. longum MK-G7, Bif. infantis Y-2, Bif. longum Y-3, Bif. longum Y-6, and Bif. longum RD-13 showed the highest bile tolerance, whereas Bif. longum MK-G7 showed a medium level of bile tolerance. Only Bif. longum MK-G7 howed much higher antibiotic resistance against both tetracycline and penicillin-G in the MIC(minimum inhibitory concentration) level of 24.8 mg/I and 0.52mg/I, respectively. Bif longum Y-6, and Bif. bifidum ATCC 29539 showed more than 80% of anti-mutagenicity against NQO(4-nitroquinolinel-oxide). Since the production of cytokines such as $TNF(tumor necrosis factor)-{\alpha}$ and IL (interleukin)-6, and NO(nitric oxide) in the macrophage cell line Raw 264.7 cells increased as Bif. longum MK-G7 cell concentration increased, ti was suggested that Bif. longum MK-G7 is able to enhance immunopotentiating activity in vitro. When freeze-dred Bif. longum MK-G7 was administered to mice at the dose of 1,2,4, and 6 g/kg of body weight, all of the mice survived in all feeding groups, proving the GRAS(generally recognized as safe) status of Bif. longum MK-G7. When fermented milk containing Bif. longum MK-G7 was administered to human volunteers, viable cell count of total bifidobacteria and anaerobes in the feces increased up to 0.5 log cycles more than before the administration. In particular, Bif. logum MK-G7 ingibited the growth of Bacteroides at the level of 1.0-1.5 log cycles.

• 한국식품영양학회지
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• 제29권6호
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• pp.1023-1029
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• 2016

정장작용, 면역체계 조절, 알레르기 저감, 콜레스테롤 경감 등 여러 기능적 효능이 알려진 프로바이오틱스 건강기능 식품이 증가하고 있다. 본 연구에서는 기능성 커피 상품개발을 위하여 커피 배합에 최적인 probiotic 균주를 선발하고자 하였다. 국내외 유통 중인 동결건조커피에서 분리한 균주 1종, 발효유스타터로 사용되는 균주 8종, Bifidobacterium 1종, Bacillus coagulans 1종으로 동결건조 후 생존율, 커피 음용 환경 생존율, 내산성 및 내담즙성을 측정하였다. Bacillus coagulans는 초기균수 $2.4{\times}10^7cfu/g$에서 동결건조 후에도 $2.0{\times}10^7cfu/g$으로 높은 생존율을 나타냈고, 커피의 음용 환경, 내산성, 내담즙성 테스트에서도 대조균인 Lactobacillus casei 균에 비하여 우수한 생존율을 나타냈다. 특히, 내산성 테스트에서는 pH 1, 120분 조건에서 Bacillus coagulans이 대조군에 비하여 3.8배 높은 생존율을 나타냈다. 이에 포자형성을 특징으로 하는 유산생성 Bacillus coagulans 균제제를 기능성 커피 배합 및 상품화에 적합한 probiotic 균주로 판단하였다.

• 한국식품영양과학회지
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• 제28권5호
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• pp.1003-1009
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• 1999

For the isolation of probiotics which may be used for the human beings and animals, we have screened the microorganisms from chicken intestines which have acid and bile tolerance and the growth inhibition of pathogenic E. coli and Salmonella typhimurium. Among them, a strain which was identified as Lactobacillus salivarius had around 66% of survival after 2h incubation in the artificial gastric juice and 9% of survival after 24h incubation in the presence of 0.3% bile salts, and showed complete inhibition against both path ogenic E. coli and Salmonella typhimurium after 24 h coincubation. Its storage stability after lyophilization could be improved by adding polyvinylpyrrolidone.

• 한국식품조리과학회지
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• 제20권6호
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• pp.658-666
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• 2004

In order to develop and commercialize high quality frozen soy yogurt, the effects of industrial proteases and commercial mixed cultures were examined on the functional properties and the sensory attributes of frozen soy yogurt. For quality improvement, soy protein isolates were primarily hydrolyzed by either Flavourzyme or Neurtrase, industrial Proteases, to reduce the beany flavor and increase the functional properties of the protein. The viable cell count of lactic acid bacteria was higher in the soy protein hydrolysates than whenuntreated. ABT-5 (L. acidophilus, Bifidobacterium lactis, and S. thermophilus) resulted in higher acid tolerance, bile acid tolerance and melt-down percent values than those with YC-X11 (Lactobacillus bulgaricus and Streptococci thermophilus). The overrun of frozen soy yogurt was improved by both Flavourzyme $(193.3\%)$ and Neurtrase $(156.7\%)$ treatments. With regard to thesensory characteristics, Flavourzyme improved the beany flavor, astringency taste, mouth feel and overall quality of frozen soy yogurts fermented with ABT-5. Further studies onproduct formulation will be needed to commercialize the frozen soy yogurt for the market.

• Journal of Microbiology and Biotechnology
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• 제22권12호
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• pp.1731-1739
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• 2012

In this study, seven strains isolated from mustard leaf kimchi were screened for their tolerance to simulated gastric and bile juices, the adhesive properties to Caco-2 cells, and the inhibition ability of Salmonella Typhimurium ATCC 29631 adhesion. Lactobacillus acidophilus GK20, Lactobacillus paracasei GK74, and Lactobacillus plantarum GK81, which were resistant to bile as well as gastric juices, possessed high bile-salt hydrolase (BSH) activity towards both sodium glycocholate and sodium taurocholate. The strongest in vitro adherence of $53.96{\pm}4.49%$ was exhibited by L. plantarum GK81 followed by L. acidophilus GK20 with adhesion levels of $40.72{\pm}9.46%$. The adhesion of these strains was significantly (p < 0.05) reduced after exposure to pepsin and heating for 30 min at $80^{\circ}C$. Addition of $Ca^{2+}$ led to a significant (p < 0.05) increase of the adhesion of L. acidophilus GK20, but the adhesion ability of L. plantarum GK81 was not different from the control by the addition of calcium. In the competition and exclusion experiment, the adhesion inhibition of S. Typhimurium by L. plantarum GK81 strain was much higher than the other strains. Moreover, the exclusion inhibition of S. Typhimurium by L. acidophilus GK20 was considerably high, although the inhibition activity of this strain was lower than L. plantarum GK81.

• 한국미생물·생명공학회지
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• 제27권1호
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• pp.23-27
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• 1999

The development and industrial application of intestinal anaerbic bacteria is highly important in the munufacture of foodstuffs and medical products. We have conducted studies, screening anaerobic intestinal bacteria for acid and bile tolerance and for pathogens suppression in the intestine of swine. One such study was taxonomic in nature and dealt with the isolate's biochemical responses. The results indicated that the BSA-131 strian ioslated. which suppressed various pathogens (13 typical strains), were identified as Lactobacillus reuterii. The strain, which named L. reuterii BSA-131, was able to tolerate acid condition down to pH2 and could also tolerate bile at 5%. The strain exhibited resistance to a range of antibiotics including, cephalexin, erythromycin, flumequine, furazolidine, gentamycin, penicillin G, norfloxacin, spectinomycin, tetracycline, tiamuline, neomycin, chloramphenicol, kanamycin etc.

• 대한수의학회지
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• 제44권4호
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• pp.581-586
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• 2004

The growth characteristics and the properties of the Enterococcus faecium (E. faecium) isolated from intestine of slaughting pig were examined in order to confirm whether it will be used practically as probiotics or not. E. faecium was identified by morphological and biochemical tests including of final confirming by API strep kit. Among 264 samples, 44 isolates (16.7%) of E. faecium were observed as an exellent growth as a range of $1{\times}10^7CFU/ml{\sim}3.3{\times}10^9CFU/ml$ in viable bacterial count on MRI medium. All isolates were shown non-haemolysis on the blood agar exception of 28 isolates shown ${\alpha}$-haemolysis and were identified as E. faecium by biochemical test using API strep enzyme kits. Eight strains (18.2%) were finally selected from which they were excellent sensitivity in showing of the acid-tolerance and the bile-tolerance in compare with reference strain.

• 한국축산식품학회:학술대회논문집
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• 한국축산식품학회 2005년도 제36차 추계 학술발표대회
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• pp.324-328
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• 2005

Lactic acid bacteria are dominant microflora in fermented kimchi. In this study, lactic acid bacteria were isolated from 5 kinds of fermented kimchi and determined their physiologic property. Total 64 of LAB were isolated from kimch samples. In this study, 8 strains of them were selected by pH and bile salt tolerance test. HFI 58, HFI 40, and Yeulmu E strain had significant cholesterol lowering effect in vitro test. These were made of special feed of chicken by WooJin B&G. A Diet was tested for 5 weeks. The feed of special material supplement HFI58 groups had significant lower cholesterol concentration in egg yolk.

• 한국미생물·생명공학회지
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• 제19권5호
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• pp.429-432
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• 1991

생균제를 제조할 목적으로 유아와 동물의 분변으로부터 내산성, 내담즙성 및 항생물질 내성균주를 분리하였다. 분리균주 중 TK-19 균주는 산에 대하여 강한 내성을 나타내었고, 500$\mu g$/ml의 담즙에서도 생육이 가능하였으며 kanamycin(30 $\mu g$/ml), streptomycin(10 $\mu g$/ml), nicin(50 $\mu g$/ml) 및 tetracycline(10 Mug/ml)에 대하여 내성을 나타내었다. TK-19 균주를 동정한 결과 Streptococcus faecium으로 판단되어 Streptococcus faecium TK-19로 명명하였다.

• 한국미생물·생명공학회지
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• 제51권4호
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• pp.403-415
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• 2023

This study aimed to isolate and identify L-(+)-lactic acid-producing bacteria from tree barks collected in Thailand and evaluate the potential strain as probiotics. Twelve strains were isolated and characterized phenotypically and genotypically. The strains exhibited a rod-shaped morphology, high-temperature tolerance, and the ability to ferment different sugars into lactic acid. Based on 16S rRNA gene analysis, all strains were identified as belonging to Weizmannia coagulans. Among the isolated strains, BKMTCR2-2 demonstrated exceptional lactic acid production, with 96.41% optical purity, 2.33 g/l of lactic acid production, 1.44 g/g of lactic acid yield (per gram of glucose consumption), and 0.0049 g/l/h of lactic acid productivity. This strain also displayed a wide range of pH tolerance, suggesting suitability for the human gastrointestinal tract and potential probiotic applications. The whole-genome sequence of BKMTCR2-2 was assembled using a hybridization approach that combined long and short reads. The genomic analysis confirmed its identification as W. coagulans and safety assessments revealed its non-pathogenic attribute compared to type strains and commercial probiotic strains. Furthermore, this strain exhibited resilience to acidic and bile conditions, along with the presence of potential probiotic-related genes and metabolic capabilities. These findings suggest that BKMTCR2-2 holds promise as a safe and effective probiotic strain with significant lactic acid production capabilities.