• Journal of Bio-Environment Control
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• v.16 no.3
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• pp.252-257
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• 2007

This study was carried out to clarify the effects of antifungal Streptomyces sp. isolated from the soil grown kiwifruit on the growth inhibition of fruit rot (Botryosphaeria dothidea) infected in kiwi fruit plants in the southwestern districts of Jeonnam. Two hundred and fifty microorganisms were isolated and examined into the antifungal activity against Botryosphaeria dothidea. We screened and isolated six bacterial strains which have a strong inhibition against Botryosphaeria dothidea. And the best antifungal strain designated as the strain #120 showing 96.0% antifungal activity against Botryosphaeria dothidea was finally selected. The strain #120 was identified as Streptomyces sp. #120 based on its morphological, physiological, biochemical and chemotaxonomic characteristics.

• CELLMED
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• v.6 no.4
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• pp.23.1-23.6
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• 2016

With the rapid developments in nanotechnology, an increasing number of nanomaterials have been applied in various aspects of our lives. Recently, pharmaceutical nanotechnology with numerous advantages has growingly attracted the attention of many researchers. Zinc oxide nanoparticles (ZnO-NPs) are nanomaterials that are widely used in many fields including diagnostics, therapeutics, drug-delivery systems, electronics, cosmetics, sunscreens, coatings, ceramic products, paints, and food additives, due to their magnetic, catalytic, semiconducting, anti-cancer, anti-bacterial, anti-inflammatory, ultraviolet-protective, and binding properties. The present review focused on the recent research works concerning role of ZnO-NP on inflammation. Several studies have reported that ZnO-NP induces inflammatory reaction through the generation of reactive oxygen species by oxidative stress and production of inflammatory cytokines by activation of nuclear factor-${\kappa}B$ ($NF-{\kappa}B$). Meanwhile, other researchers reported that ZnO-NP exhibits an anti-inflammatory effect by inhibiting the up-regulation of inflammatory cytokines and the activation of $NF-{\kappa}B$, caspase-1, $I{\kappa}B$ $kinase{\beta}$, receptor interacting protein2, and extracellular signal-regulated kinase. Previous studies reported that size and shape of nanoparticles, surfactants used for nanoparticles protection, medium, and experimental conditions can also affect cellular signal pathway. This review indicated that the anti-inflammatory effectiveness of ZnO-NP was determined by the nanoparticle size as well as various experimental conditions. Therefore, the author suggests that pharmaceutical therapy with the ZnO-NP is one of the possible strategies to overcome the inflammatory reactions. However, further studies should be performed to maximize the anti-inflammatory effect of ZnO-NP to apply as a potential agent in biomedical applications.

• Journal of Microbiology and Biotechnology
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• v.16 no.5
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• pp.716-723
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• 2006

A biosurfactant-producing bacterial strain was selected from oil-contaminated soil because of its ability to degrade crude oil and tributyrin $(C_{4:0})$. The strain was identified as Bacillus subtilis A8-8 based on its morphological, biochemical, and physiological characteristics. When B. subtilis A8-8 was grown with crude oil as the sole carbon source, the biosurfactant from the strain emulsified crude oil, vegetable oil, and hydrocarbons. Soybean oil was the optimum substrate for the emulsifying activity and emulsion stability of the biosurfactant, both of which were superior to those of several commercially available surfactants. The biosurfactant was purified by a procedure including HCl precipitation, methanol treatment, and silica-gel chromatography. The partially purified biosurfactant was analyzed by TLC (thin-layer chromatography), SDS-PAGE, and HPLC and it reduced the surface tension of water from 72 mN/m to 26 mN/m at a concentration of 30 mg/l. Therefore, the purified lipopeptide biosurfactant has strong properties as an emulsifying agent and acts as an emulsion-stabilizing agent.

• Journal of Microbiology and Biotechnology
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• v.26 no.4
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• pp.666-674
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• 2016

The bacterial strains were screened as potential starters for fermenting low-salt doenjang (a Korean traditional fermented soybean paste) using Korean doenjang based on proteolytic and antipathogenic activities under 6.5-7.5% NaCl conditions. Phylogenetic analysis based on 16S rRNA gene sequences showed that they all belonged to the genus Bacillus. Proteolytic and antipathogenic activities against Escherichia coli, Bacillus cereus, Staphylococcus aureus, Listeria monocytogenes, and Aspergillus flavus, as well as fibrinolytic, amylase, and cellulase activities of the 10 strains were quantitatively evaluated. Of these, strains D2-2, JJ-D34, and D12-5 were selected, based on their activities. The functional, phenotypic, and safety-related characteristics of these three strains were additionally investigated and strains D2-2 and D12-5, which lacked antibiotic resistance, were finally selected. Strains D2-2 and D12-5 produced poly-γ-glutamic acid and showed various enzyme activities, including α-glucosidase and β-glucosidase. Growth properties of strains D2-2 and D12-5 included wide temperature and pH ranges, growth in up to 16% NaCl, and weak anaerobic growth, suggesting that they facilitate low-salt doenjang fermentation. Strains D2-2 and D12-5 were not hemolytic, carried no toxin genes, and did not produce biogenic amines. These results suggest that strains D2-2 and D12-5 can serve as appropriate starter cultures for fermenting low-salt doenjang with high quality and safety.

• Microbiology and Biotechnology Letters
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• v.48 no.3
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• pp.373-382
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• 2020

Candidatus Carsonella ruddii is an endosymbiont that resides in specialized cells within the body cavity of plant sap-feeding insects called psyllids. The establishment of symbiotic associations is considered one of the key factors for the evolutionary success of psyllids, as it may have helped them adapt to imbalanced food resources like plant sap. Although C. ruddii is defined as a psyllid primary symbiont, the genes for some essential amino acid pathways are absent. Complete genome sequences of several C. ruddii strains have been published. However, in-depth intra-species comparison of C. ruddii strains has not yet been done. This study therefore aimed to perform a comparative genome analysis of six C. ruddii strains, allowing the interrogation of phylogenetic group, functional category of genes, and biosynthetic pathway analysis. Accordingly, overall genome size, number of genes, and GC content of C. ruddii strains were reduced. Phylogenetic analysis based on the whole genome proteomes of 30 related bacterial strains revealed that the six C. ruddii strains form a cluster in same clade. Biosynthetic pathway analysis showed that complete sets of genes for biosynthesis of essential amino acids, except tryptophan, are absent in six C. ruddii strains. All genes for tryptophan biosynthesis are present in three C. ruddii strains (BC, BT, and YCCR). It is likely that the host may depend on a secondary symbiont to complement its deficient diet. Overall, it is therefore possible that C. ruddii is being driven to extinction and replacement by new symbionts.

• Journal of Korean Society of Environmental Engineers
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• v.36 no.4
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• pp.265-270
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• 2014

Protease producing microorganisms were isolated from many kinds of food waste and fermented foods, which contains high amount and variable kinds of degraded substances. Several microorganisms were identified by 16S rRNA full sequencing analysis methods. The activity of protease was analyzed and identified in variable conditions for the application. For industrial use for biowaste treatment some proteases were isolated, identified and selected from microbial cells. And the tests were carried for the further use. The protein degrading activity at low temperature is useful for the treatment of organic waste, which contains much proteins. By the protein degradation process the organic waste can be utilized in variable fields, for example from feedstuff supplement to fertilizer for agriculture. Bacterial cells with protease activity at low temperature were isolated and identified. The optimal conditions for microbial cultivation and protease production were studied.

• Journal of Veterinary Clinics
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• v.21 no.3
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• pp.302-308
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• 2004

Sixty-six dogs diagnosed with cystolithiasis at animal clinics in the Busan area between April 2002, and April 2003, were reviewed. The chemical analysis of cystoliths from 66 dogs indicated that the predominant mineral component was struvite (45 dogs), calcium oxalate (14 dogs), or urate (6 dogs). Animals affected with struvite were grouped into four (s-1; struvite only, s-2; struvite mixed with lesser quantities of calcium oxalate or ammonium urate, s-3; nuclei and lamination, s-4; struvite nucleus surrounded by other minerals), with calcium oxalate into six(o-1; calcium oxalate monohydrate only, o-2; calcium oxalate dihydrate only, o-3; combination of calcium oxalate monohydrate and dihydrate, o-4; calcium oxalate nucleus surrounded by other minerals, o-5; 100% calcium oxalate monohydrate nucleus surrounded by 100% calcium oxalate dihydrate, o-6; mixed calcium oxalate monohydrate nucleus surrounded by mixed calcium oxalate dihydrate), and with urate into two(u-1; ammonium acid urate only, u-2; ammonium acid urate mixed with lesser quantities of other minerals). In this study, the numbers of 4 groups of struvite were (s-1; 10, s-2; 9, s-3; 21, s-4; 5), 6 groups of calcium oxalate were (o-1; 0, o-2; 1, o-3; 2, o-4; 3, o-5; 2, o-6; 6), and 2 groups of urate were (u-1; 6, u-2; 0). The data from each group was analyzed and compared. Shih Tzu(14 cases), Yorkshire terrier(10 cases), mixed-breed(10 cases) and Miniature schnauzer(7 cases) were more frequently affected than the other breeds. Females(40 cases) were affected more than males(26 cases). Twenty-nine dogs had cystoliths associated with a bacterial urinary tract infection, and uroliths tended to recur. We conclude eradication of urinary infection along with appropriate food (e.g. prescription diet) with client compliance should help in reducing the incidence or severity of the disease.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.10a
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• pp.127-127
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• 2018

Probiotics are microorganisms that have beneficial effects on the health of the host. The health promoting effect by probiotics influences suppressing harmful bacteria, prevention of constipation, blood cholesterol reduction and regulation of blood pressure. Prebiotics are used to promote the growth or activity of microorganisms. Synbiotics, which are a mixture of probiotics and prebiotics, synergize in the intestines by complementing each other. Synbiotics not only improves the viability of the probiotics while passing through the gastrointestinal tract, maintain intestinal homeostasis, but also regulate balance of harmful and useful bacterial growth. Glycine max Merr (GMM) has been widely used in Asian countries to treat cancer, obesity, oxidative stress and imbalanced immune diseases. In addition, it has been reported that dietary fiber-rich grains promote bowel movements and prevent constipation. In this study, we investigated the viability of LactobacillIus buchneri (L.buchneri) strains, known as lactic acid bacteria under conditions of gastric fluid and intestinal fluid to determine the suitability of L.buchneri as probiotics. The adhesion ability of L.buchneri to caco-2 cells was also confirmed. The present studies showed that GMM extract promoted the growth and activity of L.buchneri strains as prebiotics. Also, this results suggested that the mixture of L.buchneri and GMM extract can helps maintain intestinal health and healthy body as synbiotics and health functional food material.

• Biomedical Science Letters
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• v.13 no.1
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• pp.47-53
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• 2007

Due to wide abuse of antibiotics both in human and livestock use, the advent and spread of multidrug resistant (MDR) pathogens becomes a serious health problem all over the world. Since the development of new antibiotics is at a standstill in pharmaceutical industry, the choice of therapeutic antibiotics is getting narrower. In this study, in an effort to search new antibiotics, the antimicrobial activity of Paenibacillus DY1 isolated from Korean soil was characterized on its growth inhibition spectrum against various health threatening MDR strains, with its stability and chemical structure. Extracellular culture filtrate of Paenibacillus DY1 effectively inhibits the growth of all the tested MDR enteropathogenic Eshcherichia coli, enterohemolytic E. coli, and enterotoxigenic E. coli strains, at a similar level to that on the nonresistant control E. coli strains. It showed significant growth inhibition effect against the causative agents of class one legal communicable disease, MDR Salmonella typhi, MDR Salmonella paratyphi A, food poisoning bacteria, MDR Salmonella typhimurium, and other MDR Salmonella spp. The growth of all of 10 different MDR Shigella spp. strains and 6 different Vibrio spp. strains tested was also inhibited. The antimicrobial activity of Paenibacillus DY1 was well preserved after heat treatment, and was also stable in both alkaline and acidic environment. The antimicrobial activity was partially purified with Diaion HP20 column and TLC. By NMR study, the putative structure of the activity was postulated as an alkane having hydroxyl groups.

• Korean Journal of Poultry Science
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• v.39 no.4
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• pp.273-278
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• 2012

Staphylococcal enterotoxin B (SEB), which is a bacterial superantigen produced by Staphylococcus aureus, is associated with serious diseases, including food poisoning and atopic dermatitis. This study was performed to produce about 30 kDa of recombinant SEB protein and to immunize in chickens to acquire the specific egg yolk antibody (IgY) against the recombinant SEB. Chickens were immunized with the recombinant SEB intramuscularly in the breast muscle by injection 3 times at intervals of two weeks. Serum- and egg yolk-antibody titers of hens against SEB were highest at 4 weeks after first immunization. In western blot, anti-recombinant SEB IgY was reacted immunospecifically against the recombinant SEB and commercialized SEB. These results suggested that the recombinant SEB antigen could be used as an immunogen to elicit antibody (IgY) against SEB and the anti-recombinant SEB IgY could neutralized staphylococcal enterotoxin B effectively.