• Journal of Dairy Science and Biotechnology
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• v.37 no.3
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• pp.155-166
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• 2019

Bacteria from the genus Lactobacillus are important for the production of fermented food and dairy products, and as symbionts in human and animals. Lactobacillus acidophilus has widely been used in the production of yogurt, health foods, and even medicines. The efficacy of L. acidophilus has been proven with regards to the reduction of cholesterol, prevention and treatment of diarrhea, modulation of the immune system, suppression of cancer, etc. Using molecular biology tools, Lactobacillus acidophilus has now been reclassified into six species: L. acidophilus, L. amylovorus, L. crispatus, L gallinarium, L. gasseri, and L. johnsonii. Thus, since L. acidophilus has now been marked as a newly defined species, caution is advised when reading future publications regarding this bacterium. In this article, the results of the reclassification of L. acidophilus are mentioned after an analysis of its field inheritance was performed by my research team. Especially, L. amylovorus KU4 (formerly named as L. acidophilus KU4; KCCM 10975P) is a novel probiotic strain that is isolated from humans; it has the ability to reduce cholesterol. It has also been reported as a microorganism that effectively inhibits the growth of pathogenic E. coli. However, this Korean patent (No 10-1541280) refers to a strain obtained from calves; the origin of this strain was incorrectly labeled. Furthermore, after the discovery of L. acidophilus in 1900, its role in intestinal microbiological research was described and its utilization as a probiotic was presented.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.6
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• pp.1237-1245
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• 1997

Interspecific fusants were made from the cells of two strains of Lactobacillus genus, a streptomycin resistant Lactobacillus sp. JC-7 and a kanamycin resistant L. acidophilus 88. The morphological and physiological properties of the fusants were examined by determining bacteriocin productivity, acid-producing activity, ability of carbohydrates utilization and three important enzyme activities. The fusants produced a bacteriocin against indicator strains and fusant No. 1, 4 exhibited a larger inhibition zone compared to that of L. acidophilus 88. $\beta$-Galactosidase, phospho-$\beta$-galactosidase, lipase activities and resistance to NaCl of Lactobacillus sp. JC-7 were better than those of L. acidophilus 88. Fusant No. 3 and 7 exhibited excellent lipase activities. Protease activity and acid productivity of L. acidophilus 88 were better than those of Lactobacillus sp. JC-7. Proteasse activities of all fusants were higher than those of parental strains, and expecially fusant No. 5 and 7 exhibited excellent proteolysis ability.

• The Korean Journal of Food And Nutrition
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• v.12 no.2
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• pp.199-203
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• 1999

To evaluate antidental caries activity of polylysine cell growth and acid production of Streptococcus mutans and lactobacillus acidophilus were microbiologically monitored in anaerobic broth system containing various concentration of polylysine. The pH and heat stability of polylysine having antimicrobial activity were also examined. Two tested microbes were fairly well grown in broth containing polylysine 0.1mg/ml however inhibited at 1 and 2mg/ml of polylysine concentration. Especially lag times of Strep-tococcus mutans and Lactobacillus acidophilus were prolonged to about hour at 1.0 and 2.0 mg/ml of poly-lysine. acid production of Streptococcus mutans and lactobacillus acidophilus was also decreased by poly-lysine. Antimicrobial activity of polylysine was not affected by the change of pH and the heat treat-ment.

• Microbiology and Biotechnology Letters
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• v.17 no.2
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• pp.94-99
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• 1989

Seven gtrains of Lactobacillus produce bacteriocin being active for Lacidophilus. All strains producing bacteriocin were found to be L. acidophilus except with one strain of L. gasseri. The maximum activity of bacteriocin produced by Lactobacillus strains was obtained at a middle or late stage of the log phase, or a early stage of the stationary phase. After the maximum was reached, however, the activity was rapidly decreased. The bacteriocins were inactivated easily by the treatment with proteolytic enzymes but not with nucleolytic enzymes, suggesting that the bacteriocin was proteinaceous. The bacteriocins were different from the other previously reported lactobacillus bacteriocin in their flexibility to the treatment at 10$0^{\circ}C$. Bacteriocins of L. acidophilus ATCC 9857 and 4357 decreased in activity by the treatment with diethylether, presumably the bacteriocin contained of a lipid component. It sums likely that L. acidophilus A4 bacteriocin adsorb to a regularly arrayed layer of the cell wall.

• Korean Journal of Food Science and Technology
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• v.35 no.6
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• pp.1244-1247
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• 2003

The purpose of this study was to isolate lactic acid bacteria that produced L(+) lactic acid from infant feces. Thirteen colonies were isolated with a MRS-plate containing 0.5% $CaCO_3$ to determine their ability to produce lactic acid. Based on their lactic acid production, 10 strains of Lactobacillus were identified to assess the ratio of lactate isomer using HPLC. A strain producing L-lactic acid was identified as Lactobacillus acidophilus, using API carbohydrate fermentation patterns and physiological tests, and named KY1909. The strain exhibited good acid tolerance in an artificial gastric juice as well as high bile resistance in MRS containing 0.5% bile acids. L. acidophilus KY1909 produced D(-) and L(+) lactic acid at a ratio of 6 : 94; whereas commercial strains of Lactobacillus acidophilus produced D(-) and L(+) lactic acid at a ratio of 1 : 1. These results demonstrate the L. acidophilus KY1909 can be utilized in fermented milk products and dietary supplements as a probiotic culture.

• Korean Journal of Clinical Laboratory Science
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• v.47 no.2
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• pp.59-64
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• 2015

Lactic acid-producing bacteria such as Lactobacillus spp. function to ferment carbohydrates and produce ATP. Such Lactobacillus spp. are used for the production of commercial yogurts. Lactobacillus spp. are beneficial to the intestinal tract, and Lactobacillus acidophilus-containing yogurts have received considerable attention because of their preventive effects against early-stage cancer of the large intestine. In this study, lactic acid-producing bacteria were cultured from three different groups: commercial solid yogurt (for eating), commercial liquid yogurt (for drinking), and Lactobacillus acidophilus-containing yogurt. We first determined the optimum culture conditions for Lactobacillus spp. and then analyzed turbidity and pH in order to compare the growth abilities and lactic acid-production capacities among the groups. Finally, high-performance liquid chromatography was used to measure the lactic acid content in the culture supernatants, and the antibacterial activities against Staphylococcus aureus and Escherichia coli were compared among the three groups. The optimum culture conditions for Lactobacillus spp. were MRS medium at $25^{\circ}C$, for 24 h. The highest turbidity was found in L. acidophilus-containing yogurt, followed by liquid yogurt and solid yogurt. Similarly, the highest lactic acid production ability was found in L. acidophilus-containing yogurt, followed by liquid yogurt and solid yogurt. Culture supernatants from the three groups did not show any antibacterial activity towards S. aureus; however, supernatants derived from L. acidophilus-containing yogurt resulted in a 1.8 mm inhibitory zone against E. coli in a paper disk diffusion test. These results revealed the high level of lactic acid-production capacity and antibacterial activity in L. acidophilus-containing yogurt.

• Food Science of Animal Resources
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• v.26 no.1
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• pp.127-135
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• 2006

This experiment was carried out to examine the fermentation properties of yogurt with bovine milk and soybean milk at the mixed ratio of 2:1 and added 0.1, 0.2, 0.4 and 1.0% red ginseng extract. The effect on promoting the fermentation by additives 0.1, 0.2, 0.4 and 1.0% red ginseng extracts were higher and pH was $3.90{\sim}3.94$ when Lactobacillus acidophilus KCTC3150 and Lactobacillus salivarius ssp. salivarius CNU27 were used. Titratable acidity showed a little inhibiting due to increasing red ginseng extract content. The average viable counts of lactic acid bacteria after 15 hour culture was the highest level of $6.26{\times}10^8cfu/mL$ when Lactobacillus acidophilus KCTC3150 was used, and the additives content of red ginseng extract was 1.0% The production of lactic acid was the highest and the concentration was 332.22 mM when Lactobacillus acidophilus KCTC3150 was used, and the additives content of red ginseng extracts was 1.0% Lactose hydrolysis was completely hydrolyzed when Lactobacillus acidophilus KCTC3150 and Lactobacillus salivarius ssp. salivarius CNU27 were used. The highest viscosity of yogurt was 780 cP when Lactobacillus acidophilus KCTC3150 and Lactobacillus salivarius subsp. salivarius CNU27 were used and red ginseng extract was added 1.0% The overall acceptability, $4.17{\pm}0.64$, was the highest when Lactobacillus salivarius subsp. salivarius CNU27 was used and the additives content of red ginseng extract was 0.2%.

• Korean Journal of Food Science and Technology
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• v.24 no.6
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• pp.586-591
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• 1992

The oligosaccharide metabolism in soymilk was investigated by mixed culture with Lactobacillus acidophilus and Saccharomyces uvarum. When Saccharomyces uvarum was cultured in soywhey, change of oligosaccharide could be shown apparently. However, Lactobacillus acidophilus could not utilize oligosaccharide in soywhey for growth and lactic acid production. During the fermentation of mixed culture with Lactobacillus acidophilus and Saccharomyces uvarum, Saccaharomyces uvarum was supposed to convert oligosaccharide to monosaccharide first and then Lactobacillus acidophilus to convert these produced monosaccharide to lactic acid.

• Microbiology and Biotechnology Letters
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• v.16 no.2
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• pp.131-135
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• 1988

Lactobacillus acidophilus KFCC12731 and Saccharomyces cerevisiae KFCC32017 were incubated together in soymilk and the conditions for acid production were investigated. The acid production of Lactobacillus acidophilus was much higher when this organism was incubated with Saccharomyces cerevisiae in soymilk than when it was incubated alone. Optimum acid production by the mixed cultures of Lactobacillus acidophilus and Saccharomyces cerevisiae was achieved with the following conditions; a temperature of 34$^{\circ}C$, a 3:7-8:2 (OD 660) ratio of Lactobacillus acidophilus to Saccharomyces cerevisiae at inoculum, a 1.5% level of sucrose fortification or a 2.0-3.0 % level of skim milk powder fortification and a culture time of 12 hours or more.

• Journal of Microbiology and Biotechnology
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• v.9 no.6
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• pp.794-797
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• 1999

Lactobacillus acidophilus is known to have an inhibitory activity on growth of Helicobacter pylori and this activity has been attributed to lactic acid and antibacterial agents produced by Lactobacillus. Since every Lactobacilli produces lactic acid, an another factor must exist for L. acidophilus to inhibit H. pylori growth. In this work, the inhibitory activity of L. acidophilus on H. pylori adherence was studied. An immunoabsorbent assay using TLC plate was developed and used for screening the inhibitory activity of various Lactobacilli on H. pylori adherence. Glycolipid, the attachment site for H. pylori, was isolated from blood type O red blood cells and spotted on a TLC plate. The H. pylori adherence increased linearly with increasing amounts of glycolipid spotted on the TLC plate. Various L. acidophilus strains, but not L. casei, appeared to inhibit H. pylori adherence to glycolipid, and the adherence decreased linearly as the concentration of the Lactobacillus increased. The results show that the inhibitory activity of L. acidophilus on H. pylori adherence is an another factor for L. acidophilus to inhibit H. pylori growth.