• Title/Summary/Keyword: bacterial growth

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The Relationship between Water-Bloom and Distribution of Microorganisms That Inhibit the Growth of Cyanobacterium (Anabaena cylindrica) (수화와 시안세균(Anabaena cylindrica) 생장 억제 미생물 분포도의 상관관계)

  • Kim, Chul-Ho;Lee, Jung-Ho;Choi, Yong-Keel
    • Korean Journal of Microbiology
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    • v.34 no.4
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    • pp.188-193
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    • 1998
  • The authors examined the variations of environmental factors, the distributions of cyanobacteria, heterotrophic bacteria, and microorganisms that inhibit the growth of Anabaena cylindrica according to development and extinction of cyanobacterial bloom at a site in Daechung Dam reservoir. And certified the relationship between each other. Water temperature variated in a typical pattern. pH and concentrations of dissolved oxygen and chlorophylla was high in bloom period, and lowered with the decline of bloom. Phosphorus played as a growth-limiting factor at this study site. Total nitrogen concentration increased during blooming period, which indicated that nitrogen has been fixed by aquatic organisms such as cyanobacteria. Cyanobacteria distributed from June 17, and such cyanobacterial species as Anabaena spp., Aphanizomenon spp., Microcystis spp., Oscillatoria spp. and Phormidium spp. was detected during study period. Anabaena spp. distributed relatively highly distributed from July 23 to September 22, and disappeared completely at September 29. Heterotrophic bacterial and cyanobacterial populations varied inverse-proportionally. There was a relevancy between the variations of Anabaena spp., heterotrophic bacteria, and microorganisms that inhibit the growth of Anabaena cylindrica. Microorganisms that inhibit the growth of Anabaena cylindrica distributed from early growth phase of Anabaena spp. population to immediately after the extinction of Anabaena spp. With the population of Anabaena cylindrica growth-inhibiting microorganisms decreasing, increases of heterotrophic bacterial population followed it. Thease results indicate that microorganisms have a part in the extinction of cyanobacterial bloom, especially at its destroying period.

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Isolation and development of Bacillus subtilis S1-0210 as a biocontrol agent of gray mold of strawberry

  • Nguyen, Hang T.T.;Oh, S.O.;Hur, J.S.;Koh, Y.J.
    • Proceedings of the Korean Society of Plant Pathology Conference
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    • 2003.10a
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    • pp.98.1-98
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    • 2003
  • Antagonistic effect of bacterial strains isolated from phylloplane of strawberry plants grown In greenhouse was tested on Botrytis cinerea Among the promising bacterial strains, Bacillus sp. S1-0210 showed highest inhibition of mycelial growth of B. cinerea and a broad spectrum of antifungal activities against many plant pathogenic fungi in vitro. Bacillus sp. S1-0210 was identified as Bacillus subtilis based on the analysis of 185 rDNA as well as its biochemical characteristics. Application of wettable powder formulation of B. subtiiis S1-0210 significantly reduced the incidence of gray mold on trawberry fruits during storage. Results showed that treatment of B. subtilis S1-0210 decreased the incidence of gray mold by 4.8% whereas the incidence in control was 77.9%, indicating that the formulation of B. subtilis S1-0210 will be practically applied on strawberry fruits as a biocontrol agent of gray mold during storage.

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Antimicrobial Action of Dental Cements (치과용 시멘트의 항미생물 작용)

  • Kim, Cheol-We;Seonoo, Young-Gook;Paik, Dae-Il;Kim, Jong-Bai;Choe, Son-Jin
    • The Journal of the Korean dental association
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    • v.21 no.7 s.170
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    • pp.573-577
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    • 1983
  • The antimicrobial action of various dental cements evaluated against common micro-organisms most frequenty found within the components of the normal bacterial flora of oral cavity. They include Streptococcus mutans (2 strains), Lactobacillus acidophilus, Actinomyces viscosus, and Streptococcus sanguis. The test was done by the use of brain heart infusion (BHI) agar plates. A standard mix of each cement was made and placed on the plates which were seeded with a standard culture of microorganisms. After incubation, the halo of bacterial growth inhibition around the cement was identified and its size was measured. Some of the cements tested had obvious antibacterial effect. The cements listed in decreasing order of effectiveness are 1) zinc phosphate and oxyphosphate, 2) silicate, 3) zinc oxide-eugenol, 4) calcium hydroxide, and 5) carboxylate.

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Neutrophil Gelatinase-Associated Lipocalin and Kidney Diseases

  • Yim, Hyung Eun
    • Childhood Kidney Diseases
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    • v.19 no.2
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    • pp.79-88
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    • 2015
  • Neutrophil gelatinase-associated lipocalin (NGAL) has emerged as one of the most promising biomarkers of renal epithelial injury. Numerous studies have presented the diagnostic and prognostic utility of urinary and plasma NGAL in patients with acute kidney injury, chronic kidney disease, renal injury after kidney transplantation, and other renal diseases. NGAL is a member of the lipocalin family that is abundantly expressed in neutrophils and monocytes/macrophages and is a mediator of the innate immune response. The biological significance of NGAL to hamper bacterial growth by sequestering iron-binding siderophores has been studied in a knock-out mouse model. Besides neutrophils, NGAL is detectable in most tissues normally encountered by microorganisms, and its expression is upregulated in epithelial cells during inflammation. A growing number of studies have supported the clinical utility of NAGL for detecting invasive bacterial infections. Several investigators including our group have reported that measuring NGAL can be used to help predict and manage urinary tract infections and acute pyelonephritis. This article summarizes the biology and pathophysiology of NGAL and reviews studies on the implications of NGAL in various renal diseases from acute kidney injury to acute pyelonephritis.

Microbiological Evaluations of Retail and Refrigerated Chickens in Winter (겨울철 소매점 및 냉장 닭고기의 미생물학적 평가)

  • 고대희
    • The Korean Journal of Food And Nutrition
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    • v.12 no.2
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    • pp.109-112
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    • 1999
  • Aerobic plate counts(APC) gram-negative bacterial counts (GNC) and sensory evaluations on chic-ken carcasses during retail and refrigerated storages (3$\pm$1$^{\circ}C$ and 1$0^{\circ}C$) were evaluated. APC and GNC on whole chicken in retail store after storage of 7 days at 3$\pm$1$^{\circ}C$ increased to 3.11 and 3.89 log units com-pared to the initial controls. APC and GNC on whole chicken after storage of 7 days at 1$0^{\circ}C$ increased to 5.43 and 5.03 log units. Sensory scores of chicken carcasses obtained from retail store were in the "liked less" category after storage of 7 days compared to fresh controls. These results indicated that chicken carcasses during refrigerated (1$0^{\circ}C$) storages rapidly allowed the growth of aerobic spoilage bacteria dur-ing storage period which cluld not be microbiologically acceptable after of 7 days of 7 days.

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Bacillus subtilis YB-70 as a Biocontrol Agent of Fusarium solani causing Plant Root-Rot

  • KIM, YONG-SU;HO-SEONG LIM;SANG-DAL KIM
    • Journal of Microbiology and Biotechnology
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    • v.4 no.1
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    • pp.68-74
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    • 1994
  • A bacterial strain YB-70 which has powerful biocontrol activity against Fusarium solani causing plant root-rot resulting in considerable losses of many economical crops was isolated and selected from over 500 isolates from a ginseng rhizosphere in suppressive soil, and identified as a strain of Bacillus subtilis. In several biochemical and in vitro antibiosis tests on F. solani with culture filterates from B. subtilis YB-70, our data strongly indicated metabolites which mediated inhibition of the fungal growth were presumed to be heat-stable, micromolecular, and ethyl alcohol solutable antifungal substances. Suppression of root-rot by B. subtilis YB-70 was demonstrated in pot trials with eggplant (Solanum melongena L) seedlings. Treatment of the seedling with the bacterial suspension (1.7~1.9$\times$$10^5$ CFU/g) in F. solani-infested soil significantly reduced disease incidences by 68 to 76% after 25 to 30 days. The results supported that B. subtilis YB-70 have excellent potentials as a biocontrol agent.

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Adsorption Characteristics of Organic Compounds on the Activated Carbon Fiber(II) (섬유상활성탄(纖維狀活性炭)에 의한 유기화합물(有機化合物)의 흡착특성(吸着特性)(II))

  • Sohn, Jin-Eon;Lee, Si-Won
    • Elastomers and Composites
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    • v.24 no.2
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    • pp.105-109
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    • 1989
  • Liquid phase adsorption of organic compounds solution on the activated carbon fiber was measured by chromatographic method in a packed column. Adsorption equilibrium constant Ka of dextrose solution was found to be $72.5cm^3/g$ on ACF without bacteria growth, while in the bacterial ACF packed column Ka was $87.9cm^3/g$. It is suggested that for biological ACF there is a large contribution of bacterial activity to the adsorption equilibrium constant. Axial dispersion coefficient Ez was determined to be in proportional to flow rate and Pe=dpu/Ez independent or existence or bacteria.

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Biological Contamination Parameters of Cotton Lint as Biomarkers for Fibre Quality; A Preliminary Study

  • Lane Samantha R.;Sewell Robert D.E.;Jiang Robert
    • Fibers and Polymers
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    • v.7 no.1
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    • pp.8-11
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    • 2006
  • It has been reported for several decades that microbes, which naturally contaminate cotton fibres during crop growth and subsequent storage can have an adverse effect on the structural quality of cotton lint. Although several studies have analysed the relationship between numbers of Gram-negative bacteria or bacterial endotoxin and particular physical properties, these studies have been limited to cotton from the United States, and the possible effects of fungal contamination have not been examined in detail. This study quantified the Gram-negative bacteria and fungal cells, as well as measuring concentrations of bacterial endotoxin and fungal glucan, on cotton lint samples from international sources. Spearman's rank correlation coefficients calculated between these results and quality data analysed by an automated testing instrument revealed several significant correlations. Findings included inverse correlations between the biological contamination parameters and fibre elongation, micronaire and reflectance. The possible causes and implications of these findings were also discussed.

Effects of Sub Minimal Inhibitory Concentration of Metronidazole and Penicillin on Morphology of Aggregatibacter actinomycetemcomitans: Scanning Electron Microscopy Observation

  • Kwon, Ye Won;Lee, Si Young
    • International Journal of Oral Biology
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    • v.40 no.1
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    • pp.35-39
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    • 2015
  • Minimal inhibitory concentration (MIC) is the lowest concentration of antibiotics that inhibits the visible growth of bacteria. It has been reported that sub-MIC of antibiotics may result in morphological alterations, along with the biochemical and physiological changes in bacteria. The purpose of this study was to examine morphological changes of Aggregatibacter actinomycetemcomitans, after the treatment with sub-MIC metronidazole and penicillin. The bacterial morphology was observed with scanning electron microscope, after incubating with sub-MIC antibiotics. The length of A. actinomycetemcomitans was increased after the incubation with sub-MIC metronidazole and penicillin. Sub-MIC metronidazole and penicillin inhibited bacterial division and induced long filaments. Our study showed that metronidazole and penicillin can induce the morphological changes in A. actinomycetemcomitans.

Effects of Basil and Majoram Essential Oils with or without Ascorbic Acid on Color and Oxidative and Microbial Stability of Beef Patties

  • Chung, Hai-Jung
    • Preventive Nutrition and Food Science
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    • v.9 no.1
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    • pp.1-6
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    • 2004
  • Fresh ground beef was mixed with ascorbic acid, basil essential oil, majoram essential oil, or each essential oil combined with ascorbic acid and stored at 1 $\pm$ 1$^{\circ}C$ for 7 days. Color, lipid oxidation (TBARS formation), aerobic bacterial counts and pH were determined. Basil and majoram essential oils were effective in inhibiting color deterioration, lipid oxidation and bacterial growth. The combined addition of basil and ascorbic acid showed the highest protection against color fading, followed by majoram + ascorbic acid, and ascorbic acid alone. Basil and majoram essential oils were most effective in delaying TBARS formation (p < ().01). Ascorbic acid did not exert an antioxidative effect and even exhibited a pro-oxidant effect. The pH values of all samples increased slightly, but no significant differences were observed, either among treatments or throughout the storage time (p > 0.05).