• Asian-Australasian Journal of Animal Sciences
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• v.15 no.12
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• pp.1798-1807
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• 2002

This study was conducted to investigate lactobacillus salivarius subsp. salivarius having probiotic properties to be used as the health adjuncts with fermented milk products. Acid- and bile-tolerant lactobacillus salivarius subsp. salivarius was isolated with lactobacilli MRS broth from faeces of 80 healthy persons (infants, children and adults). It was used as a probiotic strain in fermented milk products. The pH of fermented milk decreased from pH 6.7 to 5.0 and titratable acidity increased from 0.3% to 1.0% by L. salivarius subsp. salivarius (isolation strain 20, 35, and 37), when incubated for 36 h at 37$^{\circ}C$. The number of viable cell counts of fermented milk was maximized at this incubation condition. The SDS-PAGE evidenced no significant change of casein but distinct changes of whey protein were observed by isolated L. salivarius subsp. salivarius for titratable acidity being incubated by 0.9-1.0% at 37$^{\circ}C$. All of the strains produced 83.43 to 131.96 mM of lactic acid and 5.39 to 26.85 mM of isobutyric acid in fermented products. The in vitro culture experiment was performed to evaluate ability to reduce cholesterol levels and antimicrobial activity in the growth medium. The selected L. salivarius subsp. salivarius reduced 23-38% of cholesterol content in lactobacilli MRS broth during bacterial growth for 24 h at 37$^{\circ}C$. All of the isolated L. salivarius subsp. salivarius had an excellent antibacterial activity with 15-25 mm of inhibition zone to E. coli KCTC1039, S. enteritidis KCCM3313, S. typhimurium M-15, and S. typhimurium KCCM40253 when its pH had not been adjusted. Also, all of the isolated L. salivarius subsp. salivarius had partial inhibition zone to E. coli KCTC1039, E. coli KCTC0115 and S. enteritidis KCCM3313 when it had been adjusted to pH 5.7. The selected strains were determined to have resistances of twelve antibiotic. Strains 27 and 35 among the L. salivarius subsp. salivarius showed the highest resistance to the antibiotics. These results indicated that some of the L. salivarius subsp. salivarius (strain 27 and 35) are considered as effective probiotic strains with a potential for industrial applications, but the further study is needed to establish their use as probiotics in vivo.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.3
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• pp.376-380
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• 2006

An experiment was conducted to study the effect of temperature and pH on in vitro nutrient degradability, volatile fatty acid profile and methane production. The fermenter used was the semi-continuous system, known as the rumen simulation technique (RUSITEC). Sixteen cylinders were used at one time with a volume of 800 ml, the dilution rate was set at 3.5%/hour, the infused buffer being McDougall's artificial saliva. Basal diet (9.6 g DM) used in RUSITEC consisted of (DM) 6.40 g Timothy hay, 1.86 g crushed corn and 1.34 g soybean meal. The food for the fermentation vessel was provided in nylon bags, which were gently agitated in the liquid phase. The experiment lasted for 17 d with all the samples taken during the last 5 d. Treatments were allocated at random to four vessels each and were (1) two temperature levels of $39^{\circ}C$ and $41^{\circ}C$ (2) two pH levels of 6.0 and 7.0. The total diet contained ($g\;kg^{-1}$ DM) 957 OM, 115 CP and $167MJ\;kg^{-1}$ (DM) GE. Although increase in temperature from $39^{\circ}C$ to $41^{\circ}C$ reduced degradation of major nutrients in vitro, it was non-significant. Interaction effect of temperature with pH also reflected a similar trend. However, pH showed a significant (p<0.05) negative effect on the degradability of all the nutrients in vitro. Altering the in vitro pH from 7 to 6 caused marked reduction in DMD from 60.2 to 41.8, CPD from 76.3 to 55.3 and GED from 55.3 to 35.1, respectively. Low pH (6) depressed total VFA production (61.9 vs. 34.9 mM) as well as acetate to propionate ratio in vitro (from 2.0 to 1.5) when compared to pH 7. Compared to pH 7, total gas production decreased from 1,841 ml to 1,148 ml at pH 6, $CO_2$ and $CH_4$ production also reduced from 639 to 260 ml and 138 to 45 ml, respectively. This study supported the premise that pH is one of the principal factors affecting the microbial production of volatile fatty acids and gas. Regulating the ruminal pH to increase bacterial activity may be one of the methods to optimize VFA production, reduce methane and, possibly, improve animal performance.

• Research in Plant Disease
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• v.15 no.3
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• pp.202-208
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• 2009

The genetically modified leaffolder-resistant (Cry1Ac1) rice plant was evaluated for the changes of resistance by comparing the occurrence of major diseases with a japonica type Korean rice variety, Nakdong which was the mother plant of the transgenic rice event, in greenhouse and field conditions. There was no difference in the occurrence of sheath blight and Helminthosporium blight between the two varieties in the fields. We couldn't find any difference of resistance for fungal blast and bacterial leaf blight by artificial inoculation in greenhouse. There was also no difference in the susceptibility to sheath blight in artificial inoculation tests confirming the results in the fields. The possibility of gene transfer of Bar and Cry1Ac1 from the genetically modified rice plant to naturally infected pathogens such as Fusarium moniliforme and Pyricularia oryzae in the field conditions was tested by PCR. And the possible transfer of those genes by continuous inoculation of Xanthomonas oryzae pv. oryzae and Rhizoctonia solani was also tested. However, we couldn't find any possibility of transfer of the genes in natural and artificial conditions.

• Korean Security Journal
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• no.60
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• pp.253-282
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• 2019

College students majoring in bodyguards learn and acquire bodyguard martial arts to protect the life and property of the subjects. Also, the bodyguard martial arts are helping to improve and maintain the body and spirit of the bodyguards. However, more and more students majoring in security at universities are becoming obese due to lack of time to participate in bodyguard training and excessive food intake, which could have a negative impact on their future security work as well as their health condition. In this study, the effect of 10 weeks of Judo training on body composition, blood lipid and immune function on Security Majoring obese male college students was determined to be as follows. 1. Weight(p<.05), ; body fat ratio(p<.05), BMI(p<.01) etc. of body composition after Judo training were significantly reduced, and in the case of BMI(F=4.488, p<05), there were significant differences in interaction between groups and timing. 2. After judo training, TC (p<.05) and LDL-C(p<.01) of the blood lipid showed a significant decrease. 3. After judo training, lymphocytes of leukocytes were shown to increase significantly(p<.05), lymphocytes(F=11.772, p<.01) showed significant differences among groups. 4. After judo training, IgA and IgG of immunoglobulin were shown to increase significantly (p<.05), IgA(F=7.646, p<.05) and IgG (F=14.267, p<.01) showed significant differences among groups. Considering the above results, it is thought that judo training can prevent obesity due to reduced body fat and reduce neutral fat and cholesterol, thus preventing arteriosclerotic diseases. In addition, it is expected to play a positive role in defense against human bacterial infections, inflammatory reactions, and external antigen in immune function. It is thought that this will not only prevent the bodyguards' obesity but also maintain a healthy life and improve the security work efficiency. However, some studies have shown results that are somewhat different from the results of this study, so studies on blood lipids, immune function, and exercise will require more detailed research on various methods of exercise, such as exercise time and intensity.

• Journal of Life Science
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• v.21 no.6
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• pp.845-850
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• 2011

Norovirus (NoV) causes major acute non-bacterial gastroenteritis in humans. NoV genus is a member of the family Caliciviridae, which is transmitted by contaminated food and water or from human to human. Many genotypes of genogroups I and II have been reported because of their high genetic diversity. To obtain molecular epidemiological information on gastroenteritis sporadic cases in Busan, Korea, we analyzed the nucleotide sequences of NoV strains detected during 2008~2010. We performed one step RT-PCR amplifying the open reading frame (ORF) 2 (capsid region) followed by semi-nested PCR. Fecal samples were collected from 4,071 acute gastroenteritis, and genotypes of the 421 positive samples were determined by sequence analysis. Based on partial sequence of capsid region, 7 NoV were categorized into genogroup I and 13 into genogroup II. Prevalent genotypes among gastroenteritis patients within Busan were GII.4, GI.6, GII.5 in 2008~2010. The results of this study will contribute to the currently available epidemiological data and improve public health and hygiene via development of diagnostic methods and sustainable surveillance.

• Applied Biological Chemistry
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• v.46 no.3
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• pp.229-234
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• 2003

The traditional kochujang supplemented with mushrooms (Pleurotus ostreatus and Lentinus edodes) was prepared, and changes in quality characteristics during fermentation at ambient temperature were investigated. The moisture content of kochujang increased by addition of mushroom. The titratable acidity of mushroom-added kochujang was gradually increased during fermentation. Ethanol contents of mushroom-added kochujang decreased with the addition of oyster mushroom, but increased with the addition of oak mushroom. The amino-nitrogen contents increased gradually during fermentation, resulting in significantly higher contents of 9% mushroom-added kochujang than others. The a value of kochujang decreased greatly during fermentation, but L, a and b values showed significantly higher than the control. The growth of bacteria in kochujang was delayed by the addition of mushrooms. Bacterial and yeast counts at the end of fermentation were not influenced by the addition of mushrooms. Sensory evaluation test revealed that color and flavour of kochujang were improved by the addition of mushrooms, and higher score was obtained from the addition of oyster mushroom compared to oak mushroom.

• Applied Biological Chemistry
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• v.40 no.6
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• pp.484-489
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• 1997

The characteristics of growth and esterase activity of bacterial strains isolated from acid hydrolysed soybean protein were examined. All the isolated strains having decomposition activity of p-hydroxybenzoic acid butyl ester and esterase producing activity were identified as Bacillus sp. by morphological and biochemical methods. The specific growth rates, esterase activities and p-hydroxybenzoic acid butyl ester decomposition activities of isolated strains were $0.844{\sim}1.213\;h^{-1}$, $21{\sim}222\;mU/ml$ and $5.4{\sim}8.1\;mU/ml$, respectively. In the fermentation of Bacillus sp. KB8 strain which had the highest esterase producing activity, growth, extracellular excretion and intracellular synthesis of esterase were inhibited by adding NaCl in the culture broth. Esterase producing activity gradually increased after late exponential growth phase, until maximum value of 420 mU/ml reached after 64 hours culture period. Esterase of Bacillus sp. KB8 strain was stable up to $50^{\circ}C$ for 30 minutes, but was inactivated by heating for 30 minutes at $70^{\circ}C$. The enzyme activity exponentially decreased during the incubation time at the temperatures of $60^{\circ}C$ and $65^{\circ}C$.

• Journal of Life Science
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• v.25 no.2
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• pp.180-188
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• 2015

The bacterial strain isolated from Kimchi showed antibacterial activity against Micrococcus luteus IAM 1056. The selected strain was identified as Lactococcus lactis by 16S rRNA nucleotide sequence analysis and named as Lactococcus sp. KD 28. The treatment of culture supernatant with proteinase K removed antibacterial activity, indicating its proteinaceous nature, a bacteriocin. This bacteriocin was sensitive to hydrolytic enzymes such as ${\alpha}$-chymotrypsion, trypsin, proteinase K, lipase, ${\alpha}$-amylase and subtilisin A. The bacteriocin was highly thermostable and resistant to heating at $80^{\circ}C$ for up to an hour but 50 % of the total activity was remained at $100^{\circ}C$ for 30 min. The pH range from 2.0 to 8.0 had no effect on bacteriocin activity and it was not affected by solvents such as acetonitrile, isopropanol, methanol, chloroform and acetone up to 50% concentration. The bacteriocin showed antibacterial activity against M. luteus IAM 1056, Lactobacillus delbrueckii subsp. lactis KCTC 1058, Enterococcus faecium KCTC 3095, Bacillus cereus KCTC 1013, B. subtilis KCTC 1023, Listeria ivanovii subsp. ivanovii KCTC 3444, Staphylococcus aureus subsp. aureus KCTC 1916, B. megaterium KCTC 1098 and B. sphaericus KCTC 1184. The bacteriocin was purified through ammonium sulfate concentration, SP-Sepharose chromatography and RP-HPLC. The molecular weight was estimated to be about 3.4 kDa by tricine-SDS-PAGE analysis.

• Journal of Life Science
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• v.26 no.10
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• pp.1113-1120
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• 2016

Two bacterial strains producing extracellular man nanase were isolated from doenjang, a traditionally fermented soybean paste in Korea. The isolates, WL-6 and WL-11, were identified as Bacillus subtiis on the basis of their 16S rRNA gene sequences, morphological, and biochemical properties. Two genes encoding the mannanase of both B. subtilis WL-6 and B. subtilis WL-11 were each cloned into Escherichia coli, and their nucleotide sequences were determined. Both mannanase genes consisted of 1,086 nucleotides, encoding polypeptides of 362 amino acid residues. The deduced amino acid sequences of the two WL-6 and WL-11 mannanases, designated Man6 and Man11, respectively, differed from each other by eight amino acid residues, and they were highly homologous to those of mannanases belonging to the glycosyl hydrolase family 26. The 26 amino acid stretch in the N-terminus of Man6 and Man11 was a predicted signal peptide. Both Man6 and Man11 were localized at the level of 94–95% in an intracellular fraction of recombinant E. coli cells. The enzymes hydrolyzed both locust bean gum and mannooligosaccharides, including mannotriose, mannotetraose, mannopentaose, and mannohexaose, forming mannobiose and mannotriose as predominant products. The optimal reaction conditions were 55°C and pH 6.0 for Man6, and 60°C and pH 5.5 for Man11. Man11 was more stable than Man6 at high temperatures.

• Microbiology and Biotechnology Letters
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• v.38 no.3
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• pp.322-328
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• 2010

Fermented skate is a traditional Korean food popular in Southwestern area of Korea. It has a characteristic flavor and alkaline pH. In this study we tried to determine the microbial flora in fermented skate using two different approaches. In culture-independent method, we amplified V2 region of 16S rRNA gene by PCR and cloned them into pUC18 plasmid to construct 16S rDNA fragment library. BLAST searches for the sequences obtained from this library revealed that uncultured bacterium clone 054E11.b was the most dominant flora in this fermented fish. In culture-dependent method, we diluted suspension of skate and spreaded on MRS, PCA, and MacConkey plates. We identified colonies grown on those plates by using PCR amplification of V2 region of 16S rRNA and DNA sequencing. BLAST searches of those DNA sequences resulted in totally different species with the observations from the 16S rDNA library analysis. Discrepancies of results obtained from both approaches suggest that the agar plates used in culture-dependent method may be different from the real condition of fermented skate. Therefore, results from culture-independent approach using 16S rDNA fragment library analysis may reflect real microbial flora in fermented skate.