• Asian-Australasian Journal of Animal Sciences
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• v.15 no.7
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• pp.1031-1035
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• 2002

This study was carried out to obtain conjugated linoleic acid (CLA) producing lactic acid bacteria for further study on the enzymes related to the production of CLA which has gained considerable attention and on the development as a probiotic culture. Total 34 lactic acid bacteria were isolated from 19 feces samples of healthy babies. CLA forming ability was measured spectrophotometrically by the modification of linoleate 12-cis, 11-trans-isomerase activity measuring method, and CLA of the cultures were extracted, methylated, and examined by HPLC analysis. CLA methyl ester of only one culture showing the highest value of CLA forming ability could be detected by HPLC analysis. The culture was found to be Gram positive, rods and catalase negative. It grows at $45^{\circ}C$ but not at $15^{\circ}C$, and was identified to be Lactobacillus fermentum on the basis of the biochemical characteristics and the utilization of substrates. These results provide an efficient experimental method to screen CLA producing lactic acid bacteria.

• Natural Product Sciences
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• v.20 no.2
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• pp.102-106
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• 2014

Gumiganghwal-tang (GMT) is a traditional herbal prescription used for treatment of the common cold, pain, and inflammatory diseases. Variations in the amounts of bioactive components of GMT and GMT fermented with 10 Lactobacillus strains were investigated by high-performance liquid chromatography coupled with diode array detection (HPLC-DAD). Simultaneous qualitative and quantitative analyses of eleven bioactive compounds (prim-O-glucosylcimifugin, liquiritin, cimifugin, baicalin, liquiritigenin, wogonoside, baicalein, wogonin, butylphthalide, imperatorin, and isoimperatorin) were performed, with comparison of their retention times (tR) and UV spectra with those of standard compounds. The amounts of baicalin (8.71 mg/g), liquiritigenin (5.28 mg/g) and butylphthalide (5.10 mg/g) were the major compounds in GMT. We found that L. fermentum KFRI 145 fermented wogonoside and baicalin to their aglycones, wogonin and baicalein, respectively. These results indicated that L. fermentum KFRI 145 has potential as a functional starter culture for manufacturing fermented GMT.

• Korean Journal of Microbiology
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• v.49 no.3
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• pp.253-261
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• 2013

The purpose of this study was to investigate the aflatoxin $B_1$ binding of lactic acid bacteria (LAB) isolated from Korean traditional soybean paste and to evaluate the effect of incubation conditions and physico-chemical factors on the binding ability of LAB to this mutagen. The amount of aflatoxin $B_1$ bound by Enterococcus faecium DJ22, Lactobacillus fermentum DJ35, Lactobacillus rhamnosus DJ42, and Lactobacillus pentosus DJ47 was strain specific with the percent bound ranging from 19.3% to 52.1%. However, Enterococcus faecalis DJ14, Lactobacillus panis DJ29, and Pediococcus halophilus DJ50 strains did not exhibit any of the binding ability to aflatoxin $B_1$. For most strains, the binding ability was significantly affected by the environmental conditions such as the aflatoxin $B_1$ level, incubation time and temperature, and the initial cell count of LAB. The stability of the aflatoxin $B_1$-bacteria complexes was significantly more unstable after washing. In addition, the binding stability between viable and nonviable cells was not statistically significant. Treatment with heating, acidic pH, ${\alpha}$-amylase, protease, lysozyme, or sodium metaperiodate caused a significant (P<0.05) decrease in aflatoxin $B_1$ binding for the tested strains, suggesting that carbohydrates or proteins in the cell walls may be involved in aflatoxin $B_1$ binding ability. Since the aflatoxin $B_1$ binding of LAB was significantly reduced (P<0.05) by the pretreatment of the urea, the binding force observed in this study may have resulted from hydrophobic interaction.

• Journal of The Korean Society of Grassland and Forage Science
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• v.30 no.4
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• pp.333-342
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• 2010

Corn is very important forage in Korea. The great part of them is utilized as silage. Generally, it contains a lot of grains that is feed of animal. This experiment was conducted to evaluation of fermentation ability of microbes for corn silage inoculant. Good lactic acid bacteria were isolated from good corn silage by plating MRS agar containing 0.02% sodium azide, and assessed by growing and acid producing ability in MRS broth. Six lactic acid bacteria were selected, and were found to be Gram positive, rods and catalase negative and were identified to be lactobacillus plantarum (C3-2, B13-1, CC9-1), Lactobacillus fermentum (C11-4), Lactobacillus paracasei (B14-1), and Leuconostoc lactis (A3-1) on the basis of the biochemical characteristics and utilization of substrates. Corn was ensiled at ripen stage following treatment with selected five lactic acid bacteria, two commercial inoculant, and no additive (control). After 2 month, B13-1 and CC9-1 bacteria inoculated silage were lower pH and higher lactic acid content than others treatments. The Flieg's score and grade of B13-1 and CC9-1 bacteria treated silage were higher than commercial inoculant. According to this experiment, lactobacillus plantarum B13-1 and CC9-1 strain were recommendable for good inoculant of corn silage.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.5
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• pp.648-657
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• 2014

Silage making has become a significant method of forage conservation worldwide. To determine how tomato pomace (TP) may be used effectively as animal feed, it was ensilaged for 90 days and microbiology counts, fermentation characteristics and chemical composition of tomato pomace silage (TPS) were evaluated at the 30th, 60th, and 90th days, respectively. In addition, 103 lactic acid bacteria were isolated from TPS. Based on the phenotypic and chemotaxonomic characteristics, 16S rDNA sequence and carbohydrate fermentation tests, the isolates were identified as 17 species namely: Lactobacillus coryniformis subsp. torquens (0.97%), Lactobacillus pontis (0.97%), Lactobacillus hilgardii (0.97%), Lactobacillus pantheris (0.97%), Lactobacillus amylovorus (1.9%), Lactobacillus panis (1.9%), Lactobacillus vaginalis (1.9%), Lactobacillus rapi (1.9%), Lactobacillus buchneri (2.9%), Lactobacillus parafarraginis (2.9%), Lactobacillus helveticus (3.9%), Lactobacillus camelliae (3.9%), Lactobacillus fermentum (5.8%), Lactobacillus manihotivorans (6.8%), Lactobacillus plantarum (10.7%), Lactobacillus harbinensis (16.5%) and Lactobacillus paracasei subsp. paracasei (35.0%). This study has shown that TP can be well preserved for 90 days by ensilaging and that TPS is not only rich in essential nutrients, but that physiological and biochemical properties of the isolates could provide a platform for future design of lactic acid bacteria (LAB) inoculants aimed at improving the fermentation quality of silage.

• Journal of Microbiology and Biotechnology
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• v.5 no.6
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• pp.309-314
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• 1995

Samples were collected from a commercial ethanol production plant to enumerate the bacterial contamination in each step of a starch based ethanol production process. Though the slurry of raw material used in the process carried bacteria with various colony morphology in the order of $10^4$ per ml, only the colonies of white and circular form survived and propagated through the processes to the order of $10^8$ per ml at the end of fermentation. Almost all of the bacterial isolates from the fermentation broth were lactic acid bacteria. Heterofermentative Lactobacillus fermentum and L. salivarius, and a facultatively heterofermentative L. casei were major bacteria of an ethanol fermentation. In a batch fermentation L. fermentum was more detrimental than L. casei to ethanol fermentation. In a cell-recycled fermentation, ethanol productivity of 5.72 g $I^{-1} h^{-1}$ was obtained when the culture was contaminated by L. fermentum, whilst that of the pure culture was 9.00 g $1^{-1} h^{-1}$. Similar effects were observed in a cell-recycled ethanol fermentation inoculated by fermentation broth collected from an industrial plant, which showed a bacterial contamination at the level of 10$^8$ cells per ml.

• Food Science and Biotechnology
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• v.17 no.2
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• pp.257-261
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• 2008

Previous studies have suggested a possible correlation between cell surface hydrophobicity (CSH) and stress tolerance in Bifidobacterium. In this study, the relationship was examined between CSH and environmental stress tolerance in Lactobacillus spp. By measuring the adhesion to hexadecane, 2 Lactobacillus fermentum strains- KLB 261 and KLB 231 were found to have high and low CSH, respectively. To measure their tolerance to various stresses, cells were subjected to salt (2 M NaCl), acid (pH 2), $H_2O_2$ (0.01 %, v/v), ethanol (20%, v/v), heat ($60^{\circ}C$), and cold ($-20^{\circ}C$). Compared with KLB 231, the hydrophobic KLB 261 was found to be much more resistant to the various stresses examined. After being subjected to different stresses for a period of time, KLB 261 and KLB 231 showed 50 and 0% survivability in 2 M NaCl, 108.2 and 0.6% in 0.01 %(v/v) $H_2O_2$, 40.2%(v/v), and 3.7% at $60^{\circ}C$ incubation, 4 and 0.6% at $-20^{\circ}C$, 12.9 and 0.1 % in pH 2, 33.8 and 0.2% in 20%(v/v) ethanol, respectively. Autoaggregation test and morphological observation were also conducted in an attempt to explain these differences. These results suggested that high CSH could strengthen the stress tolerance of lactobacilli.

• 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.

• Food Science of Animal Resources
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• v.20 no.3
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• pp.181-191
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• 2000

젖산균의 생장을 위한 질소, 탄소 공급원으로서 corn steep liquor의 이용 가능성을 시험하고 반응 표면 분석(Response surface metho-dology)을 이용하여 젖산균의 최적 생상 배지 조성을 연구하였다. 반응 표면 분석에서 L.fermentum의 생장배지에 첨가되 corn steep liquor와 yeast extract의 농도(p<0.01) 그리고 corn steep liquor와 yeast extract의 교호작용(P<0.05)이 L.ferm-entum의 생장에 큰 영향을 미치는 것으로 나타났으며, 이때 생균수가 최대인 corn steep liquor의 함량은 10.77%, yeast extract는 3.39%.Tween 80은 1.69%으로 예측되었다. 한편, Lc, lactis ssp. lactis 의 생장배지는 corn steep liquor 의 농도(P<0.01) 그리고 corn steep li-quor와 $\beta$-glycerophosphate disodium salt의 교호작용(P<0.05)인 Lc. lactis ssp. lactis의 생장에 큰 영향을 미치는 것으로 나타났으며 이때 생균수가 최대인 corn steep liquor의 함량은 3.5%, $\beta$-glycerophosphate disodium salt는 4.38%로 예측되었다. MRS broth와 예측된 최적 배지에서 L.fermentum의 젖산과 초산의 생성량은 각각 0.166, 0.114과 0.273, 0.081 M이고 M 17glc broth와 최적배지에서 Lc. lacti ssp. lactis의 젖산과 초산의 생성량은 각각 0.089, 0.003과 0.189, 0.003M이었다. 따라서 corn steep liquor는 L. fermentum와 Lc. lactis ssp, lactis 의 생장을 위해 질소 또는 탄소 공급원으로서 배지에 첨가 될 수 있는 우수한 농업 부산물로 판단되었다.

• Korean Journal of Microbiology
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• v.48 no.4
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• pp.309-313
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• 2012

The purpose of this study is to simultaneously detect and identify specific genus of Lactobacillus distributed in vagina of healthy women in their twenties by using multiplex primer. Vaginal fluid samples were taken from 166 women who were healthy and did not have vaginosis symptoms caused by bacterial infection. Six species of lactic acid bacteria belong to Lactobacillus genus that are known to inhabit in healthy vagina were selected to make a species-specific multiplex primer. Multiplex primer I was specified to selectively detect L. iners, L. crispatus, L. gasseri and multiplex primer II was specified to selectively detect L. acidophilus, L. jensenii, L. fermentum. L. crispatus (77%) was most frequently detected, and L. acidophilus (57%) and L. jensenii (57%) were relatively higher than others. Although the proportion of L. iners (59%) was a little higher than those of L. acidophilus and L. jensenii, this should be further validated in healthy women's vagina to be sure since they often appear in women having bacterial vaginosis and/or during the antibiotic therapy. Conclusively, the multiplex PCR technique using the species-specific primer could a useful tool to predict variation of vaginal health condition and process of recovery from vaginal disease.