• 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.

• Journal of Microbiology and Biotechnology
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• v.26 no.7
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• pp.1182-1189
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• 2016

Lactobacillus brevis ATCC 14869 exhibited a carbon catabolite derepressed phenotype that has ability to consume fermentable sugars simultaneously with glucose. To evaluate this unusual phenotype under harsh conditions during fermentation, the effects of lactic acid and hydrogen ion concentrations on L. brevis ATCC 14869 were examined. Kinetic equations describing the relationship between specific cell growth rate and lactic acid or hydrogen ion concentration were deduced empirically. The change of substrate utilization and product formation according to lactic acid and hydrogen ion concentration in the media were quantitatively described. Although the simultaneous utilization has been observed regardless of hydrogen ion or lactic acid concentration, the preference of substrates and the formation of two-carbon products were changed significantly. In particular, acetic acid present in the medium as sodium acetate was consumed by L. brevis ATCC 14869 under extreme pH of both acid and alkaline conditions.

• Journal of Life Science
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• v.33 no.4
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• pp.334-342
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• 2023

Forty species of lactic acid bacteria isolated from gajami sikhae were identified as Lactobacillus plantarum, Leuconostoc mesenteroides, Lactobacillus brevis, and Weissella paramesenteroides. 10 of the 40 strains were selected and used for the test. In this study, experiments such as those using acid and artificial gastric juice resistance, bile acid resistance, autoaggregation, coaggregation, and cell surface hydrophobicity were conducted to utilize lactic acid bacteria separated from gajami sikhae as probiotics. The separated lactic acid strains showed high survival rates through displaying resistance to acidic and artificial gastric juices; L. plantarum GS11 showed the best resistance. Also, as a result of a measurement of bile acid resistance, all lactic acid bacteria stocks showed survival of more than 100% with a probiotic number of 10⁸ to 10⁹ log CFU/ml. After evaluating cohesion to indirectly measure cell surface adhesion, autoaggregation ability was shown to be more than 46%. Measurement of xylene adhesion for cell surface hydrophobicity evaluation revealed better cell adhesion than B. subtilis, which has 32.2% hydrophobicity in isolated lactic acid strains. Antibacterial force measurement found antibacterial activity in lactic acid bacteria, excluding L. plantarum GS12 and L. plantarum GS13. Therefore, it was judged that lactic acid bacteria separated from gajami sikhae could be used as probiotics with various probiotic properties.

• Korean Journal of Food Science and Technology
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• v.40 no.6
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• pp.649-655
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• 2008

In this study, the characteristics of the lactic fermentation of gamju manufactured using a medicinal herb decoction were assessed. A bacterial strain, LAB19, which is used for the induction of lactic fermentation into gamju, was isolated from dried persimmon and identified as Leuconostoc mesenteroides on the basis of morphological, physiological, and chemotaxonomical features, and 16S rRNA sequencing analysis. After 60 hours of lactic fermentation with Leuconostoc mesenteroides LAB19 at $25^{\circ}C$, the gamju was determined to contain 141.3 g/L of reducing sugar, 5.33 g/L of acids, and 1.19 g/L of soluble phenolics. Approximately 90% of reducing sugar and 58% of acids were maltose and lactic acid, respectively. Free radical scavenging activities were retained at levels between 76.6 to 75.7% during the lactic fermentation of gamju.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.2
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• pp.245-253
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• 2020

Objective: To develop the fermentation quality and chemical composition of alfalfa (Medicago sativa Lam.) silage, plants were inoculated with different lactic acid bacteria (LAB) strains at field 24 hours before harvest. Methods: The treatment groups were as follow: silage without additive as a control and inoculated with each strains of Lactobacillus brevis (LS-55-2-2), Leuconostoc citerum (L. citerum; L-70-6-1), Lactobacillus bifermentans (L. bifermentans; LS-65-2-1), Lactobacillus plantarum (L. plantarum; LS-3-3) and L. plantarum (LS-72-2). All the silages were stored at 25℃. Parameters such as pH, microorganism and volatile fatty acid contents, crude protein, neutral detergent fiber, acid detergent fiber, net gas, metabolizable energy, organic matter digestibility, dry matter intake and relative feed value were measured to determine fermentation quality, chemical compositions and relative feed value of alfalfa silages. Results: Significant differences were found among the control and treated groups in terms of pH and microorganism contents at all opening times and crude protein, net gas, metabolizable energy and organic matter digestibility of final silage. The pH values ranged from 4.70 to 5.52 for all treatments and control silage had the highest value of overall treatments at T₇₅d silages. Volatile fatty acid of silages was not influenced significantly by inoculations. However, lactic acid content of L. bifermentans (LS-65-2-1) was higher than the other treatments. The highest metabolizable energy and organic matter digestibility were recorded from L. citerum (L-70-6-1) inoculation. In addition, no significant differences were found among treatments in terms of neutral detergent fiber, acid detergent fiber, dry matter intake and relative feed value. Conclusion: Among the treated LAB isolates, L. bifermentans came into prominence especially in terms of organic acid composition and quality characters of silages.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.3
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• pp.386-389
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• 2006

Silage is a major component of cattle rations, so the improvement of silage quality by the inoculation of lactic acid bacteria is of great interest. In this study, commercially distributed Lactobacillus plantram and Lactobacillus rhamnousas NGRI 0110 were used for ensilaging of guinea grass. The four treatments used were a control silage, a silage with cellulase addition, a silage with cellulose+L. plantram addition, and a silage with cellulose + NGRI 0110 addition. Silage quality, voluntary intake, nutrient digestibility, and the characteristics of ruminal fluid of wethers were investigated. Silage to which lactic acid bacteria were added showed low pH and acetic acid concentration and the highest lactic acid content. Dry matter and organic matter digestibility were significantly (p<0.05) increased by cellulase addition and significantly (p<0.05) higher values were observed in L. plantram- and NGRI 0110-added silage. Voluntary intake of NGRI 0110-added silage was the highest and that of control silage was the lowest. We concluded that the observed ability of NGRI 0110 to tolerate low pH and to continue lactic acid fermentation in high lactic acid concentration had also occurred in actual ensilaging. The results indicate that the addition of lactic acid bacteria might improve silage quality and increase digestibility and voluntary intake. The potential for improvement by NGRI 0110 was higher than that to be gained by the use of commercially available lactic acid bacteria.

• Journal of Marine Bioscience and Biotechnology
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• v.11 no.2
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• pp.36-41
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• 2019

This study was conducted to analyze the difference in mechanically improved properties by distinguishing α-chitin and β-chitin for Poly(L-lactic acid)(PLLA). First, dissolution of chitins was established by mixing polar solvents hexafluoroisopropanol (HFIP) and trifluoroacetic acid (TFA) in appropriate proportions. Under these conditions, the dissolved chitin was used for electrospinning with other polymers. The electrospun nanofibers of the PLLA and chitins were successfully produced. Compared to the pristine state, when chitin was added to PLLA, the tensile strength increased 1.41 times (α-chitin), by 1.61 times (β- chitin), respectively. Based on this, it was confirmed that α- and β- chitin could be strategically used for different polymers. The results also suggest that chitin can be applied to various fields as good reinforcing material as well as electrospinning.

• Journal of Food Hygiene and Safety
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• v.12 no.3
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• pp.181-187
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• 1997

Lactobacillus acidophilus NCFM, Lactobacillus casei YIT 9018, Bifidobacterium longum 8001, and Bifidobacterium longum 8025 at the level of 106 cfu/$m\ell$ were cultured with 104 cfu/$m\ell$ of Escherichia coli O157:H7 KSC 109 or Salmonella typhimurium ATCC14028, in order to verify the effects of lactic acid bacteria and bifidobacteria on the growth of the pathogens. In the mixed culture of lactic acid bacteria with E. coli O157:H7 KSC 109, Growth inhibition and atypical microcolonies of E. coli O157:H7 KSC 109 were observed. The pathogens inoculated grew for 5 hors (pH 5.3), by the time L. acidophilus NCFM reached the exponential growth phase, and then the surviving pathogens were decreased to 101 cfu/$m\ell$ after 35 hours. When L. caseiYIT 9018 was grown with the pathogens, they grew for 10 hours (pH 4.6), by the time L. casei YIT 9018 reached the end of exponential growth phase, and then the surviving pathogens were decreased drastically. Up to the stationary growth phase of lactic acid bacteria, L. acidophilus NCFM exhibited stronger inhibition against the pathogens than L. casei YIT 9018 did, which might be attributed to its faster growth. Likewise bifidobacteria inhibited the growth of the pathogens tested, bifidobaceria was weaker in the inhibitory activity than lactic acid bacteria. When Bifidobacterium longum 8001 was cultured with the pathogens, E. coli O157:H7 KSC 109 was gradually ingibited at the stationary growth phase of bifidobacteria, atypical microcolonies were formed on Levine EMB medium after 48 hours, and Salmonella grew up to 106 dfu/$m\ell$, then was drastically ingibited at the exponential growth phage of Bifidobacterium longum 8001. But when Bifidobacteriuam longum 8025 was cultured with the pathogens, the pathogens grew to the same level of Bifidobacteriuam longum 8025 was cultured with the pathogens, the pathogens grew to the same lever of Bifidobacteriuam longum 8025 after 10 hours, then the surviving pathogens were decreased drastically.

• KSBB Journal
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• v.27 no.3
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• pp.151-156
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• 2012

Lactic acid is an important product arising from the anaerobic fermentation by lactic acid bacteria (LAB). It is used in the pharmaceutical, cosmetic, chemical, and food industries as well as for biodegradable polymer and green solvent production. The poly lactic acid (PLA) is an important material for bio-plastic manufacturing process. For PLA production by new LAB, we screened LAB isolates from shellfish. A total of 28 LAB were isolated from various shellfishes. They were all Gram positive, oxidase and catalase negative. Based on API 50CHL kit, 7 strains among the 28 isolates were identified as Lactobacillus plantarum, 6 strains as Lactobacillus delbrueckii, 5 strains as Leuconostoc mesenteroides, 3 strains as Lactobacillus brevis, 2 strains as Lactococcus lactis, 1 strain as Lactobacillus salivarius, 1 strain as Lactobacillus paracasei, 1 strain as Lactobacillus pentosus, 1 strain as Lactobacillus fermentum and 1 strain as Pediococcus pentosaceu. Also, we examined the amount of total lactic acid produced by these new strains by HPLC analysis with Chiralpak MA column. One strain E-3 from Mytilus edulis was indentified as Lactobacillus plantarum and found to produce 20.0 g/L of D-form lactic acid from 20 g/L of dextrose. Further studies are underway to increase the D-lactic acid production by E-3.

• Journal of The Korean Society of Grassland and Forage Science
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• v.35 no.2
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• pp.166-170
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• 2015

This study investigated the effect of novel Lactobacillus plantarum KCC-10 and KCC-19 on the quality and fermentation characterization of alfalfa silage at the experimental field of National Institute of Animal Science, Cheonan Province, Korea, from 2013 to 2014, and this experiment consisted of the following three treatments: control without lactic acid bacteria; treatment inoculated with L. plantarum KCC-10; and treatment inoculated with L. plantarum KCC-19. The contents of crude protein, acid detergent fiber, neutral detergent fiber, total digestible nutrient and in vitro dry matter digestibility of alfalfa silage were not affected by either L. plantarum KCC-10 or KCC-19. The pH of alfalfa silage in L. plantarum KCC-10 and KCC-19 treatments decreased as compared to control. The level of lactic acid in L. plantarum KCC-10 and KCC-19 treatments increased (p<0.05), whereas the contents of acetic acid and butyric acid decreased(p>0.05). In addition, the numbers of lactic acid bacteria in L. plantarum KCC-10 and KCC-19 treatments increased as compared to control (p<0.05). Therefore, these results suggest that the inoculation of L. plantarum KCC-10 and KCC-19 into alfalfa silage can improve the quality of silage through increased lactic acid content and lactic acid bacteria.