• Journal of Industrial Technology
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• v.28 no.B
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• pp.53-57
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• 2008

From the extensive screening for small cryptic plasmid among about 23 lactic acid bacteria (LAB), 2.4 kb of cryptic plasmid was isolated from Lactobacillus farciminis strain KCTC 3681 and named as pLF24. The plasmid pLF24 was a circular molecule of 2,396 base-pairs in length with a G+C content of 38%. Two protein-coding sequences could be predicted. ORF1 and ORF2 showed homologies to plasmids of gram-positive bacteria. The replication protein coded by ORF2 and the plus origin, were similar to replication regions of other gram-positive bacteria as shown in plasmids such as pLH2, pLS141-1 and pLC2. The nucleotide sequence of pLF24 was deposited into Genbank data base with an accession number of EU429343. The newly isolated plasmid can be used for construction of shuttle vector in Lactobacillus bacteria.

• The Korean Journal of Food And Nutrition
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• v.17 no.1
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• pp.72-79
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• 2004

This study was conducted to investigate the identification of lactic acid bacteria produced ν-aminobutyric acid(GABA) from traditional salt fermented anchovy. There was no appreciable difference in the number of lactic acid bacteria from fermented anchovy. Among the types of lactic acid bacteria, three strains of lactic acid bacteria produced ν-aminobutyric acid from those sample were identified temporary as name of Lactobacillus brevis BH-21, Lactobacillus rhamnosus BH-32 and Lactobacillus plantarum BH-38 by using gram positive identification(GPI) card and API 50 kit, respectively. 3 strains of Lactobacillus sp. were found to produce GAB A in the culture of filtrate. Lactobacillus brevis BH-21 produced GABA, some of which yielded 43.2 mg/mL GABA in the medium of 0.1% glucose, 0.1% yeast extract, 0.05% polypeptone, 0.002% MgSO$_4$$.$4H$_2$O, 0.001% FeSO$_4$$.$7H$_2$O, 0.01% NaCl, 0.1% monosodium glutamate, pH 6.0. This result suggests that Lactobacillus brevis BH-21 has the potential to be developed as a strain of GABA production.

• Journal of Korean society of Dental Hygiene
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• v.4 no.2
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• pp.153-163
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• 2004

There are normal inhabitants doing medically useful functions in the body. There are many kinds of bacteria performing specific functions in the oral cavity. Two strains of lactic acid bacteria were isolated from normal inhabitants of children 's oral cavity, which inhibited the the production of halitosis by anaerobic bacteria. The authors identified the isolates by the lest using API 50 CHL medium kit. 1. Two isolates were Gram-positive bacilli and produced hydrogen peroxide. 2. The optical density was 1.286 in the supernatant of Fusobacterium nucleatum after vortexing for 30 minutes, whereas in the supernatant of combined Fusobacterium nucleatum and each isolate, they were reduced to 0.628 and 0.497, which the percentages of coaggregation between them were 29.4% and 57.8%, respectively. 3. The optical density of Fusobacterium nucleatum precipitate was 1.794 in the culture media containing cysteine and $FeSO_4$, being reduced to 1.144 and 0.915 in the coaggregated precipitates of Fusobacterium nucleatum and each isolate. 4. The optical density of Porphyromonas gingivalis precipitate was 1.932 in the culture media, being reduced to 1.170 and 1.266 in the coaggregated precipitates of Porphyromonas gingivalis and each isolate. 5. When two isolates were tested with API 50 CHL medium kit, those were identified as Lactobaciallius salivarius and Lactobacillus delbrueckii subsp. lactis.

• Journal of Microbiology and Biotechnology
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• v.29 no.12
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• pp.1925-1930
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• 2019

Carotenoids are organic pigments with antioxidant properties and are widespread in nature. Here, we isolated five microbes, each forming yellow-colored colonies and harboring C₃₀ carotenoid biosynthetic genes (crtM and crtN). Thereafter, Lactobacillus plantarum subsp. plantarum KCCP11226, which showed the highest carotenoid production, was finally selected and the produced pigment was identified as C₃₀ carotenoid 4,4'-diaponeurosporene. This strain exhibited the highest survival rate under oxidative stress and its carotenoid production was also enhanced after exposure to 7 mM H₂O₂. Moreover, it showed the highest ability to scavenge DPPH free radical. Our results suggested that L. plantarum subsp. plantarum KCCP11226, which produces 4,4'-diaponeurosporene as a natural antioxidant, may be a functional probiotic.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.5
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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.

• Microbiology and Biotechnology Letters
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• v.39 no.2
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• pp.175-181
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• 2011

Kimchi is a group of traditional fermented vegetable foods in Korea and known to be the product of a natural mixed-fermentation process carried out principally by lactic acid bacteria (LAB). According to microbial results based on conventional identification, Leuconostoc mesenteroides and Lactobacillus plantarum were considered to be responsible for the good taste and over-ripening of kimchi, respectively. However, with the application of phylogenetic identification, based on 16S ribosomal RNA gene similarities, a variety of Leuconostoc and Lactobacillus species not detected in the previous studies have been isolated, together with a species in the genus Weissella. Additionally, Lactobacillus sakei has been accepted as the most populous LAB in over-ripened kimchi. In this study, Leuconostoc and Weissella species inhibiting the growth of Lb. sakei were isolated from kimchi for future applications to do with kimchi fermentation. From 25 kimchi samples, 378 strains in the genera Leuconostoc and Weissella were isolated and 68 strains identified as Lc. mesenteroides, Lc. citreum, Lc. lactis, W. cibaria, W. confusa, and W. paramesenteroides exhibited growth inhibition against Lb. sakei. Most of the strains also had antagonistic activities against Lb. brevis, Lb. curvatus, Lb. paraplantarum, Lb. pentosus, and Lb. plantarum. Their antagonistic activities against Lb. sakei were more remarkable at lower temperatures of incubation.

• Proceedings of the Korean Society of Life Science Conference
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• 2003.05a
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• pp.119-119
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• 2003

• The Korean Journal of Food And Nutrition
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• v.25 no.4
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• pp.951-956
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• 2012

This research was carried out in order to discover acid-forming bacteria during fermentation of Makgeolli, as Makgeolli loses its commercial value due to overproduced acidic materials. In Makgeolli kept at $25^{\circ}C$, a sudden increase of acidity as well as the disappearance of yeast cells occurred at day 6, whereas the total cell count and bacterial type remained unchanged; the result implies that a succession of bacterial types, including acid forming bacteria, occurred. Two acid-forming bacteria were isolated from acidified Makgeolli and were identified as Acetobacter pasteurianus and Lactobacillus casei. When fresh and heat-treated Makgeolli were inoculated with Acetobacter pasteurianus and/or Lactobacillus casei, the greatest amount of acid was formed in Makgeolli inoculated with Acetobacter pasteurianus and Lactobacillus casei and also in Makgeolli with Acetobacter pasteurianus alone. This result indicates that Acetobacter pasteurianus is the main acidifier; furthermore, it shows the synergy effect in acid formation with Lactobacillus casei.

• Microbiology and Biotechnology Letters
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• v.46 no.3
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• pp.201-209
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• 2018

Streptococcus thermophilus, Lactobacillus delbrueckii, Lactobacillus fermentum and Lactobacillus casei were successfully isolated from indigenous Indonesian fresh milk based on the general morphological and biochemical classification as described in Bergey's manual. Verification was conducted by sequencing of 16S rRNA after selection using the classification method mentioned in the manual. All isolates exhibited antimicrobial activity against Escherichia coli and Staphylococcus aureus in the well diffusion test. The susceptibilities of the isolated S. thermophilus 24/S1 and L. delbrueckii 94/L4 against 22 different antibiotics were determined by the disc diffusion method and variable susceptibility patterns were observed. Both isolates were susceptible to amoxicillin, the most commonly prescribed antibiotic, and resistant to sulfonamide. The presence of a plasmid was not detected after extraction. S. thermophilus 24/S1 and L. delbrueckii 94/L4 starter cultures were prepared for yogurt production after 9.5 h of incubation and the yogurt was evaluated for its flavor and quality by 30 volunteers. A score of $4.93{\pm}0.45$ out of 7 was obtained as compared to the yogurt prepared using commercial starter cultures which yielded a score of $4.76{\pm}0.30$ out of 7.

• 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.