• Journal of Microbiology
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• v.45 no.6
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• pp.515-520
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• 2007

Vaginal lactic acid-producing bacteria of 80 pre-menopausal women were studied by isolation on Blood and DeMan-Rogosa-Sharpe agar, PCR with group-specific primers for Lactobacillus-denaturing gradient gel electrophoresis (DGGE), and PCR with specific primers for V3 region in 16S rRNA-temporal temperature gel electrophoresis (TTGE). Conventional isolation method on media detected only one lactobacillus (Lactobacillus brevis) while TTGE detected only Lactobacillus sp. DGGE detected seven Lactobacillus species; L. coleohominis, L. crispatus, L. iners, L. reuteri, L. rhamnosus, L. vaginalis, and Leuconostoc lactis. L. acidophilus and L. gasseri, which are prevalent in Western women, were not detected in Korean women. Furthermore, L. rhamnosus, Leuc. lactis, L. coleohominis, and Weissella cibaria, which were not previously reported in the vaginal microbiota of Korean women, were detected. The five most prevalent LABs in vaginal microbiota in Korean women were L. iners, Enterococcus faecalis, L. crispatus, Leuc. lactis, and W. cibaria.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.554-557
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• 2000

Strain JV3 was isolated from commercial Swiss cheese products and identified as a bacteriocin producer, which has bactericidal activity against Leuconostoc mesenteroides KCCM 11324. Strain JW3 was identified tentatively as Lactococcus lactis by the API test. The activity of lacticin JW3, named tentatively as the bacteriocin produced by Lactococcus lactis JW3, was detected during the mid-log growth phase, and reached a maximum during the early stationary phase, and decreased after the late stationary phase. Its antimicrobial activity on sensitive indicator cells was completely disappeared by protease IV. The inhibitory activities of lacticin JW3 were detected during treatments of up to $121\'^{circ}C$ for 15 min. Lacticin JW3 was very stable over a pH range of 2.0 to 9.0 The apparent molecular mass of lacticin JW3 was estimated to be in the region of 3-3.5kDa, which was determined by the direct detection of bactericidal activity after SDS-PAGE.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.6
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• pp.700-707
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• 2010

Effects of protease-resistant antimicrobial substances (PRA) produced by Lactobacillus plantarum and Leuconostoc citreum on rumen methanogenesis were examined using the in vitro continuous methane quantification system. Four different strains of lactic acid bacteria, i) Lactococcus lactis ATCC19435 (Control, non-antibacterial substances), ii) Lactococcus lactis NCIMB702054 (Nisin-Z), iii) Lactobacillus plantarum TUA1490L (PRA-1), and iv) Leuconostoc citreum JCM9698 (PRA-2) were individually cultured in GYEKP medium. An 80 ml aliquot of each supernatant was inoculated into phosphate-buffered rumen fluid. PRA-1 remarkably decreased cumulative methane production, though propionate, butyrate and ammonia N decreased. For PRA-2, there were no effects on $CH_4$ and $CO_2$ production and fermentation characteristics in mixed rumen cultures. The results suggested that PRA-1 reduced the number of methanogens or inhibited utilization of hydrogen in rumen fermentation.

• Journal of Applied Biological Chemistry
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• v.62 no.4
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• pp.441-446
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• 2019

The assortment of endophytic lactic acid bacteria (LAB) in kimchi derives from its raw vegetables, which include Chinese cabbage, radish, welsh onion, onion, garlic, red pepper, and ginger. These vegetables were examined during mulkimchi fermentation using gene-specific multiplex polymerase chain reaction and 16S ribosomal RNA sequence analysis. Sixteen species from five LAB genera (Leuconostoc, Lactobacillus, Lactococcus, Pediococcus, and Weissella) appeared in the raw kimchi materials. Interestingly, nine LAB species were identified in mulkimchi on fermentation day 0 as follows: Leuconostoc carnosum, Leuconostoc citreum, Leuconostoc gelidum, Leuconostoc inhae, Leuconostoc mesenteroides, Lactobacillus plantarum, Lactobacillus sakei, Lactococcus lactis, and Weissella confusa. Seven additional LAB species were present in mulkimchi at fermentation day 9 as follows: Leuconostoc gasicomitatum, Leuconostoc kimchii, Lactobacillus brevis, Lactobacillus curvatus, Lactobacillus pentosus, Pediococcus pentosaceus, and Weissella koreensis. These species corresponded completely with the LAB in kimchi vegetables. Wei. confusa was the predominant LAB during early fermentation (pH 6.20 to 4.98 and acidity 0.20 to 0.64%), while Lac. sakei, Lac. plantarum, and Wei. koreensis became dominant later in fermentation (pH 4.98 to 3.88 and acidity 0.64 to 1.26%). These results collectively demonstrate that the LAB involved in mulkimchi fermentation originates from the raw vegetables examined.

• Food Science and Preservation
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• v.6 no.4
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• pp.442-447
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• 1999

A curd yogurt was prepared by fermenting milk added with skim milk powder and purple sweet potato by culture of 5 types of lactic acid bacteria(Lactobacillus delbruekii sub. sp. lactis, Streptococcus lactis, acidity, number of viable cell, stability of purple sweet potato's pigment and keeping qualify. Among the organisms tested, the acid production and number of viable cell by the culture of L bulgaricus remarkably increased for the first 12 hem which showed 1.04${\times}$10$\^$9/ CFU/mL in number of viable cell and 4.22 In pH where as fermentation by the culture of B. bifidum was slow. After 36 hours of incubation which showed 3.3 ${\times}$ l0$\^$8/ CFU/mL in number of viable cell and 5.1 in pH. In stabilities of purple sweet potato anthocyanin pigment n fermentation, yogurt by B. bifidum was found to be most stable followed by Leuc. lactis, L. delbruekii sub. sp. lactis, L bulgaricus, but yogurt by St. lactis was not stable. When curd yogurt added with Purple sweet Potato was kept at 2∼3$^{\circ}C$ for 14 day, its keeping quality(pH, titratable acidity, number of viable cell) was relative good except product by L. bulgaricus was found to be decreased most of viable cell. After 2 weeks of keeping, pigment of yogurt was decreased by B. bifidum, stable by L. delbruekii sub. sp. lactis.

• Food Science and Biotechnology
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• v.17 no.6
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• pp.1221-1227
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• 2008

The application of the cellulase gene (celA) as a selection marker of food-grade integration system was investigated in Lactobacillus (Lb.) casei, Lactococcus lactis, and Leuconostoc (Leu.) mesenteroides. The 6.0-kb vector pOC13 containing celA from Clostridium thermocellum with an integrase gene and a phage attachment site originating from bacteriophage A2 was used for site-specific recombination into chromosomal DNA of lactic acid bacteria (LAB). pOC13 was also equipped with a broad host range plus replication origin from the lactococcal plasmid pWV01, and a controllable promoter of nisA ($P_{nisA}$) for the production of foreign proteins. pOC13 was integrated successfully into Lb. casei EM116, and pOC13 integrants were easily detectable by the formation of halo zone on plates containing cellulose. Recombinant Lb. casei EM 116::pOC13 maintained these traits in the absence of selection pressure during 100 generations. pOC13 was integrated into the chromosome of L. lactis and Leu. mesenteroides, and celA acted as an efficient selection marker. These results show that celA can be used as a food-grade selection marker, and that the new integrative vector could be used for the production of foreign proteins in LAB.

• Applied Biological Chemistry
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• v.30 no.1
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• pp.17-23
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• 1987

Soy milk prepared from soy protein concentrate was fermented with each of the following lactic acid bacteria: Lactobacillus acidophilus KFCC 12731, L. acidophilus AKU 1122, L. bulgaricus, L. casei, Leuconostoc mesenteroides and Streptococcus lactis. The effects of methionine supple mented to soy milk on the growth and acid production by each organism. were investigated. L-methionine reduced the acid production by two strains of L. acidophilus while it had no apparent. effects on the other test cultures. The inhibitory effects of L-methionine on L. acidophilus KFCC 12731 was greater than on L. acidophilus AKU 1122. The acid production by L. acidophilus KFCC 12731 was also reduced substantially by DL-methionine supplemented to soy milk while it was not affected by D-methionine. Supplementation of L-cysteine to soy milk resulted in slight reduction of acid production by L. acido philus KFCC 12731.

• Microbiology and Biotechnology Letters
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• v.30 no.2
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• pp.116-122
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• 2002

The partial 165 rDNA sequences of 6 lactic acid bacterial strains isolated from Kimchi were determined. Two strains were Leuconostoc mesenteroides and the rest were incorrectly classified and turned out to be Lactobacillus. As the case of dairy lactic acid bacteria, the strains isolated from Kimchi also had cell-envelope proteinase (CEP) activity. As the result of partial CEP gene amplification with CEP-specific primers, the expected 1.2-kb amplificate was obtained not from Leu. mesenteroides but from Lactobacillus strains. The deduced amino acid sequence of PCR product amplified from the genomic DNA of Lactobacillus pentosus KFR1821 showed 95％ and 92％ homology with those of PrtPs from Lactococcus lactis subsp. cremoris and Lactobacillus paracasei subsp. paracasei, respectively. The PCR amplificate was used as a probe and the result of Southern hybridization illuminated the location of CEP gene in chromosomal DNA of Lb. pentosus KFR1821.

• Journal of Ginseng Research
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• v.41 no.4
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• pp.524-530
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• 2017

Background: Panax ginseng is a physiologically active plant widely used in traditional medicine that is characterized by the presence of ginsenosides. Rb1, a major ginsenoside, is used as the starting material for producing ginsenoside derivatives with enhanced pharmaceutical potentials through chemical, enzymatic, or microbial transformation. Methods: To investigate the bioconversion of ginsenoside Rb1, we prepared kimchi originated bacterial strains Leuconostoc mensenteroides WiKim19, Pediococcus pentosaceus WiKim20, Lactobacillus brevis WiKim47, Leuconostoc lactis WiKim48, and Lactobacillus sakei WiKim49 and analyzed bioconversion products using LC-MS/MS mass spectrometer. Results: L. mesenteroides WiKim19 and Pediococcus pentosaceus WiKim20 converted ginsenoside Rb1 into the ginsenoside Rg3 approximately five times more than Lactobacillus brevis WiKim47, Leuconostoc lactis WiKim48, and Lactobacillus sakei WiKim49. L mesenteroides WIKim19 showed positive correlation with b-glucosidase activity and higher transformation ability of ginsenoside Rb1 into Rg3 than the other strains whereas, P. pentosaceus WiKim20 showed an elevated production of Rb3 even with lack of b-glucosidase activity but have the highest acidity among the five lactic acid bacteria (LAB). Conclusion: Ginsenoside Rg5 concentration of five LABs have ranged from ${\sim}2.6{\mu}g/mL$ to $6.5{\mu}g/mL$ and increased in accordance with the incubation periods. Our results indicate that the enzymatic activity along with acidic condition contribute to the production of minor ginsenoside from lactic acid bacteria.

• Food Science and Biotechnology
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• v.18 no.2
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• pp.396-401
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• 2009

The nucleotide sequence contains 2 open reading frames encoding a 45-amino-acid protein homologous to a transcriptional repressor protein CopG, and a 203-amino-acid protein homologous to a replication protein RepB. Putative countertranscribed RNA, a double-strand origin, and a single-strand origin were also identified. A shuttle vector, pUCL2.1, for various lactic acid bacteria (LAB) was constructed on the basis of the pCL2.1 replicon, into which an erythromycin-resistance gene as a marker and Escherichia coli ColE1 replication origin were inserted. pUCL2.1 was introduced into E. coli, Lc. lactis, Lactobacillus (Lb.) plantarum, Lb. paraplantarum, and Leuconostoc mesenteroides. The recombinant LAB maintained traits of transformed plasmid in the absence of selection pressure over 40 generations. Therefore, pUCL2.1 could be used as an E. coli/LAB shuttle vector, which is an essential to engineer recombinant LAB strains that are useful for food fermentations.