• Journal of Microbiology and Biotechnology
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• v.17 no.4
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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 the Korean Society of Food Science and Nutrition
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• v.20 no.5
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• pp.488-493
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• 1991

The characteristics of endogenous and exogenous polygalacturonase(PG) produced from L. acidophilus were investigated as one of the serial studies on the fermentation of Chinese cabbage kimchi using L. acidophilus. Apparent molecular weigth of endogenous and exogenous PG were estimated to be 420,000 and 500,000 daltons by the method of gel filtration and Vmax of the enzymes 8.0 and $0.3{\mu}mol$ galacturonic acid/ml/30min, respectively and Km of the enzymes were 4.0mg/ml. The optimum temperature, pH and salt concentration of the both enzymes were the same and appeared to $30^{\circ}C$, 5.5 and 2~3%, respectively. The activities of the endogenous and exogenous PG all were severely decreased by increasing of temperature to $90^{\circ}C\;from\;60^{\circ}C$ and its remained activities at $60^{\circ}C\;and\;90^{\circ}C$ were 50%, 58%, and 19%, 5%, respectively.

• Korean Journal of Food Science and Technology
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• v.29 no.6
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• pp.1241-1247
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• 1997

Gel-type fermented milk was prepared from milk or mixture of milk and apple juice/grape juice. Acid production (pH change) and growth of Lactobacillus acidophilus (KCTC 2182) were studied. The effects of juice addition on sensory property of fermented milk were also studied. The pH value of samples containing mixture of milk and apple juice/grape juice (25 mL : 25 mL to 5 mL : 45 mL) was lower than that of milk sample. However, number of viable cells of L. acidophilus at 21 hr in milk and samples containing juices was similar. During lactic fermentation for 24 hr, pH of all samples dropped significantly between 6 hr and 21 hr. pH values of mixture of milk and juices were lower than that of milk sample. Growth curve showed that lag phase continued to approximately 3 hr and log phase continued to approximately 15 hr in all samples. Number of viable cells in all samples was similar Sensory evaluation showed that overall acceptability of fermented milk prepared from apple juice/grape juice and milk (15 mL : 35 mL or 5 mL : 45 mL) was better than that of reference sample. The optimum ratio of mixture of juice and milk was 15 mL : 35 mL. The score values of sensory test of fermented milk prepared from mixture of grape juice and milk were slightly higher than those of mixture of apple juice and milk.

• Korean Journal of Food Science and Technology
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• v.19 no.4
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• pp.355-360
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• 1987

Among the several lactic acid bacteria, Lactobacillus acidophilus showed the highest acid production when it was cultured mixed with Sacchasomyces uvarum in soymilk. The highest acid production was obtained in 16 hrs of cultivation when the inoculation ratio of L. acidophilus and S. uvarum was 2:1 and the temperature was $30{\sim}37^{\circ}C$. The acid production was greatly enhanced by the addition of 2.0% sucrose. However, skim milk was not stimulatory in mixed culture. During mixed culture in soymilk, acid production was affected by the enzymatic reaction of yeast.

• Animal Bioscience
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• v.34 no.4
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• pp.642-651
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• 2021

Objective: This study aimed to determine the effects of different roughages in total mixed ration (TMR) inoculated with or without coculture of Lactobacillus acidophilus (L. acidophilus) and Bacillus subtilis (B. subtilis) on in vitro rumen fermentation and microbial population. Methods: Three TMRs formulations composed of different forages were used and each TMR was grouped into two treatments: non-fermented TMR and fermented TMR (F-TMR) (inoculated with coculture of L. acidophilus and B. subtilis). After fermentation, the fermentation, chemical and microbial profile of the TMRs were determined. The treatments were used for in vitro rumen fermentation to determine total gas production, pH, ammonianitrogen (NH3-N), and volatile fatty acids (VFA). Microbial populations were determined by quantitative real-time polymerase chain reaction (PCR). All data were analyzed as a 3×2 factorial arrangement design using the MIXED procedure of Statistical Analysis Systems. Results: Changes in the fermentation (pH, lactate, acetate, propionate, and NH3-N) and chemical composition (moisture, crude protein, crude fiber, and ash) were observed. For in vitro rumen fermentation, lower rumen pH, higher acetate, propionate, and total VFA content were observed in the F-TMR group after 24 h incubation (p<0.05). F-TMR group had higher acetate concentration compared with the non-fermented group. Total VFA was highest (p<0.05) in F-TMR containing combined forage of domestic and imported source (F-CF) and F-TMR containing Italian ryegrass silage and corn silage (F-IRS-CS) than that of TMR diet containing oat, timothy, and alfalfa hay. The microbial population was not affected by the different TMR diets. Conclusion: The use of Italian ryegrass silage and corn silage, as well as the inoculation of coculture of L. acidophilus and B. subtilis, in the TMR caused changes in the pH, lactate and acetate concentrations, and chemical composition of experimental diets. In addition, F-TMR composed with Italian ryegrass silage and corn silage altered ruminal pH and VFA concentrations during in vitro rumen fermentation experiment.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2004.10a
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• pp.375-379
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• 2004

Probiotic 활성이 높은 L. acidophilus 30SC의 생존성을 증진시키기 위한 기초자료를 얻고자, 열처리 동안 새로이 발현되는 단백질을 일차원 및 이차원 전기영동을 이용하여 확인하였으며, 세포 모양을 주사전자현미경을 사용하여 관찰하였다. $55^{\circ}C$의 heat shock에는 L. acidphilus 30SC의 사멸이 있는 것으로 나타났다. 나머지 처리구는 $37^{\circ}C$에서 계속 배양한 것과 별다른 차이를 나타내지 않았다. $45^{\circ}C$로 heat shock을 준 경우 $37^{\circ}C$에서 배양한 것과 거의 동일하였다. $55^{\circ}C$에서 15분 heat shock을 준 경우 약 22kDa와 25kDa의 단백질들이 새로이 발현된 것으로 나타났으나, 24 kDa와 27kDa로 추정되는 단백질의 발현정도는 낮았음을 확인하였다. 이차원 전기영동을 실시한 결과, $37^{\circ}C$와 비교할 때 $55^{\circ}C$로 heat shock을 준 경우 새로이 5개의 protein spot을 발견할 수 있었다. 그러나 6개의 단백질 spot은 $55^{\circ}C$ heat shock에서 소실된 것으로 확인되어 추가적인 단백질의 분석이 필요한 것으로 생각되었다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.1
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• pp.35-40
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• 2000

The effect of levanheptaose produced by levanase from Streptomyces sp. 366L on principle intestinal microflora was investigated. The reaction product, levanheptaose, was used as a carbon source for various intestinal microflora. As a results, Bifidobacterium adolescentis, Lactobacillus acidophilus, and Eubacterium limosum grew effectively in the in vitro experiment, whereas Clostridium perfringens, E. coli, and Staphylococcus aureus did not. Therefore levanheptaose seems to promote selectively the growth of B. adolescentis and L. acidophilus. In the in vivo experiment, the effect of levanheptaose on the growth of intestinal microflora, $\beta$-fructosidase activity, pH, and butyrate concentration were examined in rats. Apparently, the number of fecal Bifidobacteria, the amount of butyrate, and $\beta$-fructosidase activity were increased, whereas total aerobes and pH were reduced in rats fed by levanheptaose diets, compared with those of control diets. We concluded that those effects may be beneficial in improving gastrointestinal health.

• Korean Journal of Food Science and Technology
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• v.17 no.3
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• pp.192-196
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• 1985

Eight strains of Lactobacilli(a, b, b', c, d, e, f and g) were isolated from seven Korean liquid-yogurts(A, B, C, D, E, F and G), and identification and tolerance-test to digestive fluids were carried out. Isolate a from yogurt A and isolate a from yogurt E were identified as L. casei, isolate b from yogurt B as L. acidophilus, isolate d from yogurt D as L. bulgaricus, isolate f from yogurt F as L. helveticus, and isolate b' from yogurt B, isolate c from yogurt C and isolate g from yogurt G as L. jugurti, respectively. Isolate f(L. helveticus) and c(L. jugurti) showed high tolerance to artificial gastric juice but didn't to bile acid. Isolate b(L. acidophilus), a(L. casei), and e(L. casei) showed high tolerance to both artificial gastric juice and bile acid, but isolate d(L. bulgaricus), b'(L. jurgurti) and g(L. jugurti) did not.

• Korean Journal of Food Science and Technology
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• v.39 no.2
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• pp.164-168
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• 2007

The principal objective of this study was to determine the effects of wheat flour ferment cultured with Lactobacillus acidophilus, specifically with regard to the preservation of noodles. The results showed that the addition of ferment to wheat flour during noodle preparation reduced the pH of the noodles, and no significant difference was observed in the L and ${\Delta}E$ values of the noodles adding 5% ferment. Total bacterial levels were decreased in the wet noodles to which more than 10% ferment was added, by a factor of log $10^3$ as compared to the levels seen in the control during storage. Deterioration became apparent at 4 days of storage in regular wet noodles, but did not occur until 6 days in the wet noodles to which 5% ferment was added, and not until 8 days of storage in the noodles to which 10% ferment was added. Cooked noodles deteriorated at 8 days after the beginning of storage, but the addition of 5% and 10% ferment extended that time to 12 days and 14 days, respectively. It was concluded that flour ferment cultured with L. acidophilus exerts favorable preservation effects on noodles and breads.

• The Korean Journal of Food And Nutrition
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• v.15 no.1
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• pp.42-50
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• 2002

This experiment was carried out to investigate the effect of Maesil extract on the acid production and growth of yoghurt starter in the skim milk medium. The Maesil extract was added to skim milk medium fur 1% to 9% and the medium was fermented by single or mixed culture of 4 types of lactic acid bacteria(Streptococcus thermophilus, Lactobacillus acidophilus, Lactobacillus, bulgaricus, Lactobacillus casei). The chemical composition of Maesil, the changes in acid production (titratable acidity, pH) and number of viable cells of the medium during lactic fermentation in skim milk added with Maesil extract, and the keeping quality of curd yoghurts containing Maesil extract have determined. The composition of Maesil were 0.4% crude ash, 4.1% dietary fiber, 4.66%l citric acid, 0.264% total sugars and 405.34mg% vitamin C. The addition of Maesil extract stimulated the acid production and propagation of the lactic acid bacteria. Among the treatments tested, the addition of 3% Maesil extract with the mixed culture of Streptococcus thermophilus, Lactobacillus acidophilus and Lactobacillus casei produced the highest amount of acid(1.23%) and showed the highest number of viable cell counts(3.6$\times$10$^{11}$ cfu/mL). When the curd yoghurts containing 3% Maesil extract with the mixed culture of the lactic acid bacteria were kept at 4$^{\circ}C$ and 2$0^{\circ}C$ for 30 days, it was showed that the changes of titratable acidity, pH and number of viable cell counts of the lactic acid bacteria were not significantly different during storage. Therefore the keeping quality of the curd yoghurts adding 3% Maesil extract showed relatively good at the shelf-life.