• Asian-Australasian Journal of Animal Sciences
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• v.17 no.10
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• pp.1411-1416
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• 2004

The objective of this work was to isolate a microorganism, able to produce high lactate dehydrogenase (LDH) activity, for use as a microbial feed additive. The LDH is an important enzyme for lactate conversion in the rumen, thereby possibly overcoming lactic acidosis owing to sudden increases of cereal in the diets of ruminants. In the present study, various bacterial strains were screened from a variety of environments. Among the isolated microorganisms, strain FFy 111-1 isolated from a Korean traditional fermented vegetable food called Kimchi showed the highest enzyme activity, along with retaining strong enzyme activity even in rumen fluid in vitro. Based on morphological and biochemical characteristics as well as compositions of cellular fatty acids plus API analyses, this strain was identified as Lactobacillus sp. The optimum temperature and pH for growth were found to be 30$^{\circ}C$ and pH 6.5, respectively. A maximum cell growth of 2.2 at $A_{650}$ together with LDH activity of 2.08 U per mL was achieved after 24 h of incubation. Initial characterization of FFy 111-1 suggested that it could be a potential candidate for use as a direct-fed microbial in the ruminant animals.

• The Korean Journal of Mycology
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• v.43 no.3
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• pp.180-184
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• 2015

For selection of effective antagonists for control Sclerotinia rot of lettuce, 29 bacteria were isolated from soil in Korea. The bacterial isolates M27 and RM43 identified as Bacillus sp, were selected as prospective agents for inhibiting mycelial growth of Sclerotinia sclerotiorum and Sclerotinia minor. Among the selected isolates, Bacillus amyloliquefaciens M27 effectively suppressed incidence of Sclerotinia rot by Sclerotinia sclerotiorum and Sclerotinia minor in the lettuce nursery.

• Culinary science and hospitality research
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• v.12 no.2 s.29
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• pp.168-183
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• 2006

The purpose of this study was to investigate quality characteristics of roll bread with the addition of Chungkukjang powder(0, 5, 10, 15, 20%). The antioxidative activity of antioxidative substances produced from several bacterial strains isolated from fermented foods were tested by DPPH $(\alpha,\alpha’-diphenyl-\beta-picrylhydrazyl)$ free radical scavenging activity. The most optimal medium condition for the production of antioxidative substance from Bacillus sp. FF-7 was 2% galactose as carbon source and 1% tryptone as nitrogen source. In color values, with increasing Chungkukjang powder content, the "lightness" (p<0.05) decreased in the crumb bread, while the redness(p<0.05) and yellowness(p<0.05) increased. The volume and specific volume of roll bread with 5.0% Chungkukjang powder were the highest(p<0.05). In the rheology measurements for the roll bread, the hardness (p<0.05) decreased with the addition of 5.0% Chungkukjang powder, but then increased with further additions of Chungkukjang up to 10.0%. Highest sensory scores for color, flavor, taste(p<0.05), texture(p<0.05) and overall acceptance(p<0.05) were obtained from roll bread with 5.0% Chungkukjang powder and control. From the results of this study, it was assumed that the development of food products using Chungkukjang is prospective in response to health-oriented consumers.

• Journal of Dairy Science and Biotechnology
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• v.35 no.3
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• pp.162-168
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• 2017

Mastitis is a common and serious infection of the mammary gland in dairy cattle and has a major economic impact on the production of milk and dairy products. Bacterial mastitis is caused by several pathogens and is most frequently associated with coagulase-negative staphylococci (CNS). Although CNS are typically associated with subclinical or mild mastitis, the importance of CNS has increased as these pathogens have emerged as predominant mastitis-related pathogens in many countries. CNS can cause persistent infections, resulting in increased milk somatic cell counts and thereby affecting milk quality and decreasing milk production. Globally, Staphylococcus chromogenes, S. epidermidis, and S. simulans are the predominant CNS species in dairy cattle mastitis. Antibacterial resistance of CNS varies with species, and most CNS are susceptible to vancomycin and resistant to penicillin and tetracycline. As the most frequently isolated CNS species, some strains of S. chromogenes exhibit phenotypic resistance to ampicillin, erythromycin, oxacillin, penicillin, and tetracycline. Some strains of S. epidermidis and S. haemolyticus are only susceptible to vancomycin and rifampicin. Therefore, more studies are needed to achieve the control and prevention of CNS as environmental pathogens.

• Food Science and Biotechnology
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• v.16 no.3
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• pp.355-360
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• 2007

During the traditional production process of yugwa, a Korean traditional oil-puffed snack, three bacterial isolates, 12, 37, and B1 from waxy rice slurry were characterized by using the molecular techniques, and the quality of the yugwa prepared by using three isolates was examined in relation to physical and sensory properties. Isolates 37 and B1 were identified as Lactobacillus sp. by 16S rDNA sequence analysis, while isolate 12 was as Bacillus amyloliquefaciens by gyrA sequence analysis. Waxy rice inoculated with isolate 12 demonstrated the lowest hardness and the highest peak and [mal viscosity. Yugwa prepared from isolate 12-inoculated waxy rice indicated the lowest hardness and the highest volume expansion, the key characteristics of yugwa. This result presents the possibility for the use of a starter in the commercial production of yugwa and other rice-based snacks.

• Biomolecules & Therapeutics
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• v.19 no.3
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• pp.302-307
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• 2011

Peptidoglycan (PGN) is detected in inflammatory cell-rich regions of human atheromatous plaques. The present study investigated the effects of PGN on CC chemokine ligand 3 (CCL3) expression, which is elevated in the atherosclerotic arteries, and determined cellular factors involved in PGN-mediated CCL3 up-regulation in mononuclear cells, with the goal of understanding the molecular mechanisms of inflammatory responses to bacterial pathogen-associated molecular patterns in diseased arteries. Exposure of human monocytic leukemia THP-1 cells to PGN resulted in enhanced secretion of CCL3 and profound induction of the CCL3 gene transcript. Both events were abrogated by oxidized 1-palmitoyl-2-arachidonosyl-sn-phosphatidylcholine, an inhibitor of Toll-like receptors 2/4. Pharmacological inhibitors such as U0126, SP6001250, Akt inhibitor IV, rapamycin, RO318220, diphenyleneiodonium chloride, and N-acetylcysteine also significantly attenuated PGN-mediated CCL3 up-regulation. However, polymyxin B, LY294002, and SB202190 did not influence CCL3 expression. We propose that PGN contributes to enhanced CCL3 expression in atherosclerotic plaques and that Toll-like receptors (TLR2), Akt, mTOR, mitogen-activated protein kinase, and reactive oxygen species are involved in that process.

• Journal of Microbiology and Biotechnology
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• v.10 no.4
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• pp.435-440
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• 2000

A pathogenic fungus causing balloon flower root rot (Platycodon grandiflorum) was isolated from naturally infected roots. The microbial characteristics of the isolated microorganism were similar to those of Rhizoctonia solani. About 500 bacterial species from field soils were screened for a biological agent against the above-mentioned putative pathogen, and several bacteria with the antifungal activity were isolated. Among them, the isolated JS2 was identified as Pseudomonas aeruginosa. This strain showed a broad spectrum of antifungal activity potentially. When the antifungal substance was purified from a broth culture of JS2, it was identified as 2,4-diacetylphloroglucinol (Phl).

• The Plant Pathology Journal
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• v.30 no.1
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• pp.102-108
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• 2014

The bacterial strain T-9, which shows strong antifungal activity, is isolated from the soils of Samcheok, Gangwondo and identified as Paenibacillus kribbensis according to morphological and taxonomic characteristics and 16S rRNA gene sequence analysis. The P. kribbensis strain T-9 strongly inhibits the growth of various phytopathogenic fungi including Botrytis cinerea, Colletotricum acutatum, Fusarium oxysporum f. sp. radicis-lycopersici, Magnaporthe oryzae, Phytophthora capsici, Rhizoctonia solani, and Sclerotium cepivorum in vitro. Also, the P. kribbensis strain T-9 exhibited similar or better control effects to plant diseases than in fungicide treatment through in vivo assays. In the 2-year greenhouse experiments, P. kribbensis strain T-9 was highly effective against clubroot. In the 2-year field trials, the P. kribbensis strain T-9 was less effective than the fungicide, but reduced clubroot on Chinese cabbage when compared to the control. The above-described results indicate that the strain T-9 may have the potential as an antagonist to control various phytopathogenic fungi.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2006.04a
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• pp.77-90
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• 2006

Beta-amyloid peptide (A$\beta$) is a major component of senile plaques and its aggregation is considered to play a critical role in pathogenesis of Alzheimer's disease (AD). Aggregation of A$\beta$ could result from both increased synthesis and decreased degradation of A$\beta$. Our laboratory is interested in understanding the mechanism of A$\beta$ degradation in brain. Recently our laboratory identified a bacterial gene (SKAP) from Streptomyces sp KK565 whose protein product has an activity to cleave A$\beta$ and thus reduce the A$\beta$-induced neurotoxicity. The sequence analysis showed that this gene was closely related to aminopeptidase. Maldi-Tof analysis showed that the recombinant SKAP protein expressed in E. coli cleaves both A$\beta$ 40 and A$\beta$ 42 at the N-terminal of A$\beta$ while an aminopeptidase from Streptomyces griseus (SGAP) cleaves at the C-terminal. We also identified a mammalian homolog of SKAP and the recombinant mammalian protein expressed in Sf-9 insect cells showed a similar proteolytic activity to SGAP, cutting A$\beta$ at the C-terminus. I well discuss the detailed mechanism of the enzyme action and its functional implication in AD.

• BMB Reports
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• v.34 no.6
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• pp.531-536
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• 2001

Three zymographic techniques using casein, fibrin, and gelatin as substrates in SDS-PAGE were compared based on three aspects: (1) The proteolytic pattern of extracellular enzymes from the three bacterial strains, Bacillus sp. DJ-1, DJ-2, and DJ-3. (2) The enzymatic sensitivity of their activity on zymogram gels. (3) The stability of stained zymogram gels with Coomassie brilliant blue in the destaining solution. There was no significant difference on the pattern of extracellular enzymes from the three strains. The bands in the fibrin gel were clearer and more distinct from the extensive destaining process. It was also shown that the gelatin gel revealed the highest enzymatic sensitivity among the three gels, based on the densitometric analysis. In the casein gel, a trace that could be mistaken as a proteolytic band appeared around 40-50 kDa.