• Food Science and Biotechnology
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• v.15 no.1
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• pp.86-90
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• 2006

Two lactic acid bacteria (LAB) with high ${\gamma}$-aminobutyric acid (GABA)-producing capacity were isolated from naturally aged cheese. Examination of the biochemical features using an API kit indicated that the two strains belonged to Lactobacillus. They were gram positive, rod-type bacteria, and fermented arabinose, melezitose, melibiose and xylose, but did not utilize cellobiose or trehalose. 16S rDNA sequencing analysis confirmed that they were Lactobacillus buchneri and Lactobacillus sp. They were accordingly named as Lactobacillus buchneri OPM-1 and Lactobacillus sp. OPM-2, and could produce GABA from MRS broth supplemented with 10 g/L of monosodium glutamate (MSG) at a productivity of 91.7 and 116.7 mg/L/hr, respectively. Cell extracts of L. buchneri OPM-1 and Lactobacillus sp. OPM-2 showed glutamate decarboxylase (GAD) activity, for which the optimum pH and temperature were 5.5 and $30^{\circ}C$, respectively.

• Korean Journal of Microbiology
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• v.51 no.1
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• pp.61-67
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• 2015

Recently, change of Western pattern diet and lifestyle is caused by various metabolic disorders and chronic diseases. These diseases need to take medicine regularly. Also, many people take health functional food, various vitamins and nutritional supplements in order to maintain a healthy life. But, there was no study about affects taking medicines against bacteria with gastrointestinal relevance. This study was performed by antibacterial activity test to evaluate the influence of a long time or commonly used medication. As a result, medicines of Vitamins & Minerals or Central nervous system show antibacterial activity against beneficial enteric bacteria and harmful enteric bacteria. Dexibuprofen of the Anti-inflammatory Drugs that acts on the central nervous system has shown high antibacterial activity at beneficial enteric bacteria strains (Lactobacillus casei, Lactobacillus rhamnosus) and harmful enteric bacteria (Staphylococcus aureus). Also, fenofibric acid of the antilipemic agents that acts on the Cardiovascular & Hematopoietic system has shown high antibacterial activity at beneficial enteric bacteria strains (Lactobacillus casei). Vitamins & Minerals appeared antibacterial activity against most intestinal bacteria. Vitamin B-Complex/with C and vitamin C were especially high with beneficial enteric bacteria strains (Bifidobacterium infantis) and harmful enteric bacteria (E. coli, E. aerogenes, S. flexneri, S. Typhimurium, S. aureus). Therefore, these results indicate that variously taking medicines have generally antibacterial activity against harmful enteric bacteria strains and beneficial enteric bacteria strains.

• Korean Journal of Agricultural Science
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• v.47 no.3
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• pp.437-443
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• 2020

The aim of this study was to evaluate the effect of Lactobacillus acidophilus probiotic (LAP) product supplementation on the blood profile, fecal noxious gas emission, and fecal shedding of lactic acid bacteria and coliform bacteria in healthy adult Beagle dogs. In total, 14 Beagle dogs with an average initial body weight of 10.19 ± 0.61 kg were randomly assigned into two dietary treatments,with and without LAP supplementation, for a 28-day feeding trial. At the end of the experiment, there was no significant (p > 0.05) difference in the concentration of serum total cholesterol, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), white blood cell (WBC), red blood cell (RBC), blood lymphocyte percentage, fecal hydrogen sulfide (H₂S) and total mercaptans (R.SH) emission, and fecal coliforms counts. However, the serum concentrations of the triglyceride and fecal ammonia (NH₃) emission of the LAP treatment were significantly (p < 0.05) decreased in the group compared with the CON dogs. Fecal total lactic acid bacteria counts were significantly (p < 0.05) increased in the LAP treatment. In conclusion, the supplementation of LAP in Beagle dog diets could decrease the blood triglyceride level and enhance the gut Lactobacillus count which may have positive effects on dogs.

• Korean Journal of Microbiology
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• v.33 no.4
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• pp.247-251
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• 1997

Effects of amino acids on the lactic acid bacteria in kimchi were studied. 73 different lactic acid bacteria have been isolated during the kimchi fermentation at $15^{\circ}C$. Among these bacteria, dextran formers were occupied by 69.9%, of which Leuconostoc and Lactobacillus were 4.1% and 65.8%, respectively. All isolates didn't grow in a medium added with 500 ppm of tyrosine, whereas such an inhibition was not exhibited in kimchi with the same concentration of tyrosine. In kimchi added with tyrosine the lactic acid bacteria were less diverse than in the natural kimchi but the ratio of dextran formers were similar. As contrasted with natural kimchi, Leuconostoc was rather increased up to 41.4% and Lactobacillus was decreased down to 29.3%. Dominant species in each genus were Leu. mesenteroides and Lac. minor. Thus it is believed that tyrosine had inhibition effect for the growth of most Lactobacillus in kimchi.

• Korean Journal of Food Science and Technology
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• v.31 no.1
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• pp.189-195
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• 1999

Isoflavones of soy milk were mainly present as sugar conjugates such as genistin and daidzin which a glucosyl residue was attached to their aglycones, genistein and daidzein through ${\beta}-glycosidic$ bond, respectively. When soy milk containing sucrose as a sugar source was fermented with lactic acid bacteria, small amount of lactic acid $(0.16{\sim}0.29%)$ was produced but isoflavone conjugates were fully hydrolyzed. Supplementation of glucose or lactose was required for normal lactic acid production and affected the hydrolysis of isoflavone conjugates in some lactic acid bacteria. In the case of Lactobacillus delbrueckii subsp. delbrueckii KCTC 1047, glycosidic bond of isoflavone was fully hydrolyzed regardless of glucose supplementation. But only $25{\sim}40%$ of daidzin and $65{\sim}80%$ of genistin was hydrolyzed when glucose was added into soy milk in the other lactic acid bacteria, Lactobacillus bulgaricus KCTC 3188, Lactobacillus casei KCTC 3109, Lactobacillus delbrueckii subsp lactis KCTC 1058, Lactobacillus lactis KCTC 2181. The hydrolyzing enzyme, ${\beta}-glucosidase$ produced by lactic acid bacteria except Lactobacillus delbrueckii subsp. delbrueckii KCTC 1047 could be considered as inducible in the fermentation of soy milk and its production was decreased when glucose was added.

• Journal of Microbiology
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• v.38 no.3
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• pp.137-144
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• 2000

The genetic relationship of six Lactobacillus strains and five laboratory isolated form fermented milk were determined by a random amplified polymorphic DNA(RAPD)-Polymease chan reaction (PCR) method. With 42 random primers. the result were analyzed by using the NTSYS-PC software for phenetic analysis. it revealed that all tested bacteria were divided into three distinct clusters. The clusters implied three subgenuses existed for the genus Lactobacillus, which were previously proposed by Rogosa and Sharpe. From the results, it was also possible to determine that the isolated Lactobacillus strains from fermented milk were grouped into L. acidophilus or L. bulgaricus. Interestingly. the three tested L. casei strains were divided into different clusters implying different subgenuses, i.e., Thermobacterium (L. casei YIT 9018) and Streptobacterium(L. casei CHR. Hansen and L.casei ATCC 4646). According to the distance matrix generated by an UPGMA program, the isolated bacteria LT01 and LT02 were determined as a subspecies of L. bulgaricus. The HK01, HK02 and HK03 were very closely related to either L. acidophilus or L. case YIT 9018. Hence, RAPD-PCR appears to be a very practical method to determine the genetic relationships of the Lactobacillus species and to characterize the unknown Lactobacillus strains at the subspecies level.

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.3
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• pp.459-465
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• 1999

The inhibition degree of the isolated bacteria on plaque formation of Streptococcus mutans, and the effect of these bacterial genus on the concentration of total bacteria in saliva were assessed with the following. The effectiveness of the isolated bacteria on the inhibition of plaque formation was assessed culturing Streptococcus mutans in the beaker with orthodontic wires. The mean weight of plaque produced on a wire was 152mg in the culture of Streptococcus mutans only, whereas being reduced to 4mg, 78mg, or 72mg in the combined culture of Streptococcus mutans and Enterococcus durans, Lactobacillus acidophilus, or Streptococcus oralis. The colony forming units (CFU) of Streptococcus mutans were $3.6{\times}10^8$ per ml in the culture of Streptococcus mutans, only, wheras being $1.4{\times}10^6,\;5.6{\times}10^6,\;or\;3.8{\times}10^6$ per ml in the combined culture of Streptococcus mutans and Enterococcus durans, Lactobacillus acidophilus, or Streptococcus oralis. When saliva from children was inoculated on brain heart infusion agar, the colony forming units of bacteria were $4.8{\times}10^6\;to\;1.3{\times}10^9$ per ml of saliva. The concentration of Enterococcus, Lactobacillus, or Streptococcus inhibiting Streptococcus mutans in saliva was not proportioned to that of total bacteria replicated on brain heart infusion agar. These results indicate that the isolated bacteria inhibited the replication of Streptococcus mutans, resulting into inhibiting the formation of plaque, but the concentration of Enterococcus, Lactobacillus, or Streptococcus inhibiting Streptococcus mutans, in saliva might not affect the total bacterial concentration of saliva.

• Preventive Nutrition and Food Science
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• v.17 no.3
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• pp.217-222
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• 2012

This study was carried out to investigate the isolation and characterization of lactic acid bacteria (LAB) from naturally fermented sauce-type kimchi. Sauce-type kimchi was prepared with fresh, chopped ingredients (Korean cabbage, radish, garlic, ginger, green onion, and red pepper). The two isolated bacteria from sauce-type kimchi were identified as Pediococcus pentosaceus and Lactobacillus brevis by 16S rDNA sequencing and tentatively named Pediococcus sp. IJ-K1 and Lactobacillus sp. IJ-K2, respectively. Pediococcus sp. IJ-K1 was isolated from the early and middle fermentation stages of sauce-type kimchi whereas Lactobacillus sp. IJ-K2 was isolated from the late fermentation stage. The resistance of Pediococcus sp. IJ-K1 and Lactobacillus sp. IJ-K2 to artificial gastric and bile acids led to bacterial survival rates that were 100% and 84.21%, respectively.

• Journal of Radiation Industry
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• v.6 no.2
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• pp.177-180
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• 2012

The acid and bile tolerance changes of 5 different lactic acid bacteria (LAB; Lactobacillus paracasei, Lactobacillus casei, Lactobacillus acidophilus, Lactobacillus plantarum, and Lactobacillus debruekii) with gamma irradiation were evaluated. The abilities of LAB to survive in the acidic conditions at the stomach and the bile acidic conditions at the beginning of the small intestine are the key functions for applying LAB to probiotics. In the results, all of LAB survived more than 50% after incubation in PBS (pH 2.5) for 2 hr, which indicated more than half of LAB are possible to pass through the stomach. However, gamma irradiation decreased the acid tolerances of LAB. The bile tolerances of all bacteria except Lactobacillus acidophilus were observed to survive at a 3% oxgall concentration in MRS, and 1 kGy of gamma irradiation to LAB did not affect any bile tolerances changes. But gamma irradiated Lactobacillus casei and Lactobacillus casei (3 kGy) showed decreasing survival rate with oxgall added MAS agar. In conclusion, gamma irradiation should be applied to yogurt or fermented foods with care because LAB could be changes their properties on acid and bile tolerances.

• Korean Journal of Microbiology
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• v.27 no.4
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• pp.404-414
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• 1989

Attempts were made to isolate and identify Gram-positive or lactic acid bacteria in Kimchi fermentation. Species diversity depended on isolation media and temperatures, and diversity tended to be reduced with decrease of temperature. MRS and KM (natural medium prepared from Kimchi materials) were suitable respectively for isolation and present number of species. Identification of isolates was performed by dichotomous identification schemes arranged on the basis of Bergey's manual of Systematic Bacteriology (1986). Gram-positive bacteria isolated at different temperatures (5, 15, $25^{\circ}C$) were 5 species of Leuconostoc, 4 species of Streptococcus, 3 species of Pediococcus, 2 species of Bacillus and 18 species of Lactobacillus. Species with high frequency of appearance were Lactobacillus plantarum, Streptococcus raffinolactis, Leuconostoc mesenteroides subsp. mesenteroides at $25^{\circ}C$, L. plantarum, Lactobacillus fructosus, L. mesenteroides subsp. mesenteroides at $15^{\circ}C$ and L. mesenteroides subsp. mesenteroides, Leuconosotoc paramesenteroides, Lactobacillus maltaromicus at $15^{\circ}C$. In general, Kimchi fermentation was achieved by Lactobacillus spp. (59.7% frequency) at $25^{\circ}C$ and Leuconostoc spp. (65.2% frequency) at $5^{\circ}C$. Pediococcus cerevisiae and Streptococcus faecalis which have been so far known as bacteria of Kimchi fermentation were not isolated.