• 한국축산식품학회지
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• 제41권2호
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• pp.343-352
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• 2021

The objective of this study was to evaluate the effects of Lactobacillus acidophilus ATCC 43121 and L. fermentum MF27 on biochemical indices in the serum, cholesterol metabolism in the liver and mucin expression in the gallbladder in lithogenic diet (LD)-induced C57BL/6J mice to determine the preventive effects of lactobacilli on gallstone formation. By the end of 4 wk of the experimental period, mice fed on a LD with high-fat and high-cholesterol exhibited higher levels of total and low-density lipoprotein cholesterol in the serum compared to mice fed on control diet or LD with L. acidophilus ATCC 43121 (LD+P1; p<0.05). Cholesterol-lowering effects observed in the LD+P1 and LD with L. fermentum MF27 (LD+P2) groups were associated with reduced expression of 3-hydroxy-3-methylglutaryl coenzyme A reductase in the liver compared to the LD group (p<0.05). Furthermore, expression of the gel-forming mucin, including MUC5AB and MUC5B, was suppressed in the LD+P1 and LD+P2 groups compared to the LD group (p<0.05). Therefore, steady intake of both L. acidophilus ATCC 43121 and L. fermentum MF27 may have the ability to prevent the formation of cholesterol gallstones in LD-induced C57BL/6J mice.

• Journal of Microbiology and Biotechnology
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• 제17권4호
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• pp.655-662
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• 2007

This study examined the effects of Lactobacillus acidophilus ATCC 43121 (LAB) on cholesterol metabolism in hypercholesterolemia-induced rats. Four treatment groups of rats (n=9) were fed experimental diets: normal diet, normal $diet+LAB(2{\times}10^6\;CFU/day)$, hypercholesterol diet (0.5% cholesterol, w/w), and hypercholesterol diet+LAB. Body weight, feed intake, and feed efficiency did not differ among the four groups. Supplementation with LAB reduced total serum cholesterol (25%) and VLDL+IDL+LDL cholesterol (42%) in hypercholesterol diet groups, although hepatic tissue cholesterol and lipid contents were not changed. In the normal diet group, cholesterol synthesis (HMG-CoA reductase expression), absorption (LDL receptor expression), and excretion via bile acids (cholesterol $7{\alpha}-hydroxylase$ expression) were increased by supplementation with LAB, and increased cholesterol absorption and decreased excretion were found in the hypercholesterol diet group. Total fecal acid sterols excretion was increased by supplementation with LAB. With proportional changes in both normal and hypercholesterol diet groups, primary bile acids (cholic and chenodeoxycholic acids) were reduced, and secondary bile acids (deoxycholic and lithocholic acids) were increased. Fecal neutral sterol excretion was not changed by LAB. In this experiment, the increase in insoluble bile acid (lithocholic acid) reduced blood cholesterol level in rats fed hypercholesterol diets supplemented with LAB. Thus, in the rat, L. acidophilus ATCC 43121 is more likely to affect deconjugation and dehydroxylation during cholesterol metabolism than the assimilation of cholesterol into cell membranes.

• Journal of Microbiology and Biotechnology
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• 제17권5호
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• pp.774-783
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• 2007

In the present study, acidocin 1B, a bacteriocin produced by Lactobacillus acidophilus GP 1B, exhibited profound inhibitory activity against a variety of LAB and pathogens, including Gram-negative bacteria, and its mode of action was to destabilize the cell wall, thereby resulting in bactericidal lysis. Acidocin 1B was found to be heat stable, because it lost no activity when it was heated up to $95^{\circ}C$ for 60 min. It retained approximately 67% of the initial activity after storage for 30 days at $4^{\circ}C$, and 50% of its initial activity after 30 days at $25^{\circ}C$ and $37^{\circ}C$. The molecular mass of acidocin 1B was estimated to be 4,214.65 Da by mass spectrometry. Plasmid curing results indicated that a plasmid, designated as pLA1B, seemed to be responsible for both acidocin 1B production and host immunity, and that the pLA1B could be transformed into competent cells of L. acidophilus ATCC 43121 by electroporation. Our findings indicate that the acidocin 1B and its producer strain may have potential value as a biopreservative in food systems.

• Journal of Dairy Science and Biotechnology
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• 제14권2호
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• pp.195-206
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• 1996

Cholesterol assimilated by Lactobacillus acidophilus ATCC 43121 was not metabolically degraded in that most of it was recovered with the cells. Cells grown in the presence of cholesterol micelles and bile salts were more resistant to Iysis by sonication than those grown in their absence, suggesting a possible alteration of cellular membranes. Cholesterol assimilation occurred during growth at pH 6.0, the amount of which was more than that by cells grown without pH control. Cholesterol assimilated by cells was recovered in the membrane fractions of cells both grown at pH 6.0 and without pH control. The effect of unsaturated fatty acids on cholesterol assimilation was not clear, since there was no significant (P> 0.05) difference in the amount taken up from micelles prepared using L-${\alpha}$-phosphatidylcholine, dioleoyl or L-${\alpha}$-phosphatidylcholine, distearoyl. Without Tween 80, little, if any, cell growth or cholesterol uptake was observed. In the presence of 0.05% Tween 80, cholesterol uptake increased dramatically as did growth. However, as the amount of Tween 80 increased beyond 0.05%, cholesterol uptake decreased while the amount of growth remained the same.

• 한국식품과학회지
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• 제34권5호
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• pp.856-861
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• 2002

유산균의 활용성을 증진시키기 위한 방안으로서 건식 Hybridization system을 이용하여 장용성 피복재로 유산균분말의 표면처리를 실시하였다. 전자현미경 관찰 결과 표면처리는 유산균의 표면을 매끄러운 구형의 모양으로 변화시켰으며 표면처리를 통한 분체복합화 과정에서 유산균의 활력은 유의적인 변화없이 유지되었다. 또한 유산균의 내염성은 처리여부에 따른 유의적 변화를 보이지 않음으로써 표면처리 과정 중 유산균 세포막의 물리적 손상은 일어나지 않은 것으로 판단된다. 표면처리된 유산균의 내산성은 처리전후에 차이를 나타내지 않았으나 이는 균주 자체의 높은 내산성에 기인한 것으로 판단된다. 표면처리 후의 유산균은 유의적으로 높은 열저항성을 보여 표면처리가 유산균의 내열성 향상을 위하여 활용될 수 있는 가능성을 나타냈다. 조사된 장용성 피복재 중 Sureteric은 다른 피복재에 비하여 우수한 표면 처리 효과를 보였으며 유산균분말의 표면처리를 위한 적합한 처리조건은 유산균의 초기입도가 $100{\sim}200\;{\mu}m$, 유산균:피복재의 혼합비율(w/w)은 9 : 1, 처리속도는 15,000 rpm, 3분이었다.

• Journal of Microbiology and Biotechnology
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• 제26권10호
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• pp.1675-1686
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• 2016

We characterized the probiotic properties of Lactobacillus helveticus strains KII13 and KHI1 isolated from fermented cow milk by in vitro and in vivo studies. The strains exhibited tolerance to simulated orogastrointestinal condition, adherence to Caco-2 cells, and antimicrobial activity. Both L. helveticus strains produced bioactive tripeptides, isoleucylprolyl-proline and valyl-prolyl-proline, during fermentation of milk. KII13 showed higher in vitro cholesterol-lowering activity (47%) compared with KHI1 (28%) and L. helveticus ATCC 15009 (22%), and hence, it was selected for in vivo study of cholesterol-lowering activity in atherogenic diet-fed hypercholesterolemic mice. For the study, mice were divided into four groups (viz., normal diet control group, atherogenic diet control group (HCD), KII13-atherogenic diet group (HCD-KII13), and Lactobacillus acidophilus ATCC 43121-atherogenic diet group (HCD-L.ac) as positive control). The serum total cholesterol level was significantly decreased by 8.6% and 7.78% in the HCD-KII13 and HCD-L.ac groups (p < 0.05), respectively, compared with the HCD group. Low-density lipoprotein cholesterol levels in both HCD-KII13 and HCD-L.ac groups were decreased by 13% and 11%, respectively, compared with the HCD group (both, p < 0.05). Analysis of cholesterol metabolism-related gene expression in mice liver showed increased expression of LDLR and SREBF2 genes in mice fed with KII13. By comparing all the results, we conclude that L. helveticus KII13 could be used as a potential probiotic strain to produce antihypertensive peptides and reduce serum cholesterol.

• 한국축산식품학회지
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• 제26권4호
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• pp.511-516
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• 2006

발효 소시지의 제조에 starter로 사용한 균주를 선발하기 위해 각 유산균 균주들의 ACE 저해 활성, 콜레스테롤 흡착능력, 발효 육제품 저장 중 S. aureus에 대한 저해 황성을 평가하였다. ACE 저해 활성은 L. plantarum L167이 가장 우수하였고(58.75%), 콜레스테롤 흡착 능력이 우수한 균주로는 L. plantarum L155를 선발하였다. 박테리오신을 생산하는 P. damnosus를 starter로 이용하여 제조한 발효 소시지에 S. aureus를 접종하여 상온 저장 중 생균수를 측정한 결과 저장 35일째에 대조구에 비하여 1 log의 균수 감소 효과가 나타났다.