• Title/Summary/Keyword: E. coli concentration

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Allelopathic Potential and Substances from Cork Tree (Pbellodendron amurense Rupr.)

  • Park, Young-Goo;Choi, Myung-Suk;Yang, Jae-Kyung;Paik, Ki-Hyon
    • Journal of the Korean Wood Science and Technology
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    • v.29 no.3
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    • pp.92-98
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    • 2001
  • Allelopathic effects of the cork tree (Phellodendron amurense Rupr.) on several crops and soil miro-organisms were assessed using germination bioassay and antimicrobial assay, and allelochemicals were identified. In a germination bioassay, extract of cork tree inhibited at high concentration on germination of several crop seeds such as cabbage, lettuce, and cucumber. However, aqueous extracts inhibited powerfully growth of test organisms such as Streptococus aureus, S. aureus, S. typhimurium, and E. coli as bacteria, and Candida albicans as yeast, and Botrytis cineria and Alternata alternaria as fungi.. The cork tree extract showed strong antimicrobial activities against isolated soil fungi. The allelochemicals were separated using Silica gel, Sephadex LH-20 gel column chromatography and HPLC. The substances were analyzed by UV spectrometry and EI-mass spectrometry. The active allelochemicals were identified as isoquinoline alkaloids, berberine and palmatine.

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Synthesis of $\alpha$-L-Aspartyl-L-phenylalanine Methyl Ester from an Artificial Polypeptide

  • Choi, Soon-Yong;Kim, Hyun-Soo;Lee, Se-Yong
    • Journal of Microbiology and Biotechnology
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    • v.2 no.1
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    • pp.1-6
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    • 1992
  • The aspartame, $\alpha$-L-aspartyl-L-phenylalanine methylester, is an artificial sweetener. Taking advantage of the fact that the aspartame is a derivative of dipeptide, synthesis of aspartame from the artificial polypeptide made by an artificial gene has been attempted. The artificial polypeptide (LAP32), a polymer of tripeptide (aspartyl-phenylalanyl-lysine), was purified from the E. coli cells harboring a recombinant plasmid containing the artificial gene. This polypeptide was then digested with trypsin and carboxypeptidase B to produce dipeptide (Asp-Phe). Using the esterase activity of $\alpha$-chymotrypsin, the dipeptide was directly converted into Asp-Phe methylester in a water-methanol system. When the methanol concentration in reaction mixture was 25%, 50% of dipeptide was converted to the dipeptide methylester without producing any by-products.

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Characteristics and Analysis of Natural Pine-Needles Extract (천연 솔잎추출물의 특성 및 분석)

  • Sung, Ki-Chun
    • Journal of the Korean Applied Science and Technology
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    • v.21 no.4
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    • pp.320-326
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    • 2004
  • We have extracted the natural pine-needles to use ethanol in solvent, and could obtain the refined oil component from pine-needles extract. We have tested the antimicrobial effect from microbe experiment and analyzed with ICP/OES, GC/MS. we could obtain the next conclusion from the result of this experiment. In the first result of this experiment we could know that in case of increasing concentration of pine-needles, the number of microbe decreased more and more. Also we could know that the refined oil component of pine-needles appeared the sterilization effect of S-aureus and E-coli after 96hrs and 120hrs. So we could know that the refined oil component of appeared effect to microbe. In the second result of this experiment we could know that inorganic materials of Ca, Mg, V, Mn etcs from pine-needles detected to ICP/OES analysis and the aromatic compounds from refined oil component of pine-needles was certificated to GC/MS analysis.

Chemical Modification of Yeast Farnesyl Protein Transferase Expressed in E. coli

  • Kim, Hyun-Kyung;Yang, Chul-Hak
    • Bulletin of the Korean Chemical Society
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    • v.27 no.4
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    • pp.529-534
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    • 2006
  • Chemical modification of the S. cerevisiae farnesyl protein transferase (FPT) with CMC, phenylglyoxal and DEPC resulted in enzyme inactivation, depending upon the reagent concentration. The peptide substrate GST-PEP-I, a GST-fused undecapeptide mimicking the C-terminus of $p21^{Ki-ras}$, protected the enzyme against inactivation by CMC which is specific to either aspartate or glutamate, while the other substrate farnesyl pyrophosphate (FPP) showed protection against phenylglyoxal which is the specific modifier of arginine residues, dependent on the substrate concentrations. Neither of the two substrates protected the enzyme against histidine inactivation by DEPC. It is suggested that there is at least one aspartate or glutamate residue at the peptide substrate binding site, and that at least one arginine residue is located at the binding site of FPP. There also seems to be at least one histidine residue which is critical for enzymic activity and is exposed toward the bulk solution, excluded from the substrate binding sites.

Physiological Effects of Levanoligosaccharide on Growth of Intestinal Microflora (Levanoligosaccharide의 장내미생물의 생육에 미치는 생리효과)

  • 이태호;강수경;박수제;이재동
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.29 no.1
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    • pp.35-40
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    • 2000
  • The effect of levanheptaose produced by levanase from Streptomyces sp. 366L on principle intestinal microflora was investigated. The reaction product, levanheptaose, was used as a carbon source for various intestinal microflora. As a results, Bifidobacterium adolescentis, Lactobacillus acidophilus, and Eubacterium limosum grew effectively in the in vitro experiment, whereas Clostridium perfringens, E. coli, and Staphylococcus aureus did not. Therefore levanheptaose seems to promote selectively the growth of B. adolescentis and L. acidophilus. In the in vivo experiment, the effect of levanheptaose on the growth of intestinal microflora, $\beta$-fructosidase activity, pH, and butyrate concentration were examined in rats. Apparently, the number of fecal Bifidobacteria, the amount of butyrate, and $\beta$-fructosidase activity were increased, whereas total aerobes and pH were reduced in rats fed by levanheptaose diets, compared with those of control diets. We concluded that those effects may be beneficial in improving gastrointestinal health.

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Antimutagenic Activity of Asterina pectinifera (별불가사리의 항돌연변이 활성)

  • 함정혜;한영환;박창훈;이동웅
    • YAKHAK HOEJI
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    • v.43 no.6
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    • pp.771-775
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    • 1999
  • The antimutagenic activities of the total extract and several fractions of starfish, Asterina pectinifera (Asteriidae), were investigated in vitro by SOS chromotest with Escherichia coli PQ37 and Ames test with Salmonella typhimurium TA100. When various fractions was tested, the chloroform and butanol fractions showed low induction factors, which means both fractions increased antigenotoxicity against the base substitution mutagen MNNG. Even though higher antigenotoxic effect of the chloroform fraction, no effective result of Ames test was found in revertant formation of S. typhimurium TA100. The most effective antigenotoxic and antimutagenic fraction was a butanol one: i.e., When 0.5 mg/tube of butanol fraction was applied, the induction factor was 0.68. As the concentration of the fraction was increased the formation of revertants of S. typhimurium TA100 by about 81%. There was no cytotoxic effect of butanol fraction against S.typhimurium TA100. This result might be useful for further study to search a possible anticancer agent from the starfish, Asterina pectinifera.

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Antimicrobial Activity and Bactericidal Activity of Caesalpinia sappan L. Extract (소목 추출물의 항균력 및 살균소독력)

  • Lee, Jin-Young;Min, Kyung-Jin
    • Journal of Environmental Health Sciences
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    • v.37 no.2
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    • pp.133-140
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    • 2011
  • Antimicrobial activity and bactericidal activity of Caesalpinia sappan L. extracts were investigated against five food-borne pathogens, E. coli, S. aureus, S. typhimurium, B. cereus and L. monocytogenes. Methanol extract of Caesalpinia sappan L. revealed antimicrobial activities against five pathogens. In particular, by paper disc diffusion the highest activity was shown against L. monocytogenes. Antimicrobial activities of methanol extracts showed the most potent activities, but hexane fraction had no activity. Fractions of ethyl acetate and butanol turned out to have higher antimicrobial activities against Gram(+) bacteria than Gram(-) bacteria. The minimum inhibitory concentration against five food-borne pathogens was 1.563 mg/ml on Gram(+) bacteria and 3.125 mg/ml on Gram(-) bacteria. The result of antimicrobial activity in a shaking flask method showed that bacterial growth rate fell by more than 99.999% at 3.125 mg/ml of methanol extract. The highest rate of viable reduction (99.998%) was shown at 0.781 mg/ml of methanol extract against L. monocytogenes. After five minutes of reaction between test strains and methanol extracts, the growth rates of five kinds of bacteria were reduced by more than 99.999% at a concentration of 100 mg/ml. Therefore, it is suggested that methanol extracts of Caesalpinia sappan L. can be developed as a natural sanitizer or disinfectant.

Antimicrobial activity of Prunus mume extract to oral microbes (매실추출물(PME)의 구강 미생물에 대한 항균작용)

  • Jang, Jong-Hwa;Kim, Young-In;Lee, Hyun
    • Journal of Korean society of Dental Hygiene
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    • v.14 no.1
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    • pp.109-115
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    • 2014
  • Objectives : Prunus mume has been used for the folk medicine from old times. The purpose of the study was to investigate the antimicrobial activity of prunus mume extract to various oral microbes. Methods : This study was carried out to examine the antimicrobial effect of Prunus mume extract against oral microbes. Data were collected using a Dentocult SM Strip mutans and Dentocult LB Strip mutans from April 5 to May 4, 2013. A total of 36 experimental and 32 control group were selected for this study. Results : The MIC of Prunus mume extract was tested for 0.39% in S. mutans, S. salivarius and S. auerus, 0.78% in S. mitis, S. equi and E. coli. In vivo, experimental group showed significantly the lower Streptococcus mutans levels by the use of the gum contained Prunus mume extract from 15 days compared with control group(p=0.012). The reduction was more significant in Lactobacilli level of the experimental group than the control group(p=0.022). Conclusions : These findings suggest that the oral products containing Prunus mume extracts is effective in preventing oral diseases.

Effects of Lactic Acid Bacteria Inoculant on Fermentation Quality and in vitro Rumen Fermentation of Total Mixed Ration

  • Choi, Yeon Jae;Lee, Sang Suk
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.39 no.3
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    • pp.132-140
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    • 2019
  • Fermented total mixed ration (TMR) is a novel feed for ruminants in South Korea. The purpose of this study was to evaluate the effects of lactic acid bacteria (LAB) on the quality of TMR and in vitro ruminal fermentation. Strains of three LAB spp. (Lactobacillus plantarum, L. brevis, L. mucosae) were used in fermentation of TMR. Inoculations with the three LAB spp. lowered pH and increased concentrations of lactic acid, acetic acid, and total organic acid compared to non-LAB inoculated control (only addition of an equivalent amount of water) (p<0.05). Bacterial composition indicated that aerobic bacteria and LAB were higher. However, E. coli were lower in the fermented TMR than those in the control treatment (p<0.05). Among the treatments, L. brevis treatment had the highest concentration of total organic acid without fungus detection. Gas production, pH, and ammonia-nitrogen during ruminal in vitro incubation did not differ throughout incubation. However, ruminal total VFA concentration was higher (p<0.05) in the LAB spp. treatments than the control treatment at 48 hours. Overall, the use of L. brevis as an inoculant for fermentation of high moisture. TMR could inhibit fungi growth and promote lactic fermentation, and enhance digestion in the rumen.

The Antimicrobial Activity of Essential Oil from Dracocephalum foetidum against Pathogenic Microorganisms

  • Lee, Saet-Byoul;Cha, Kwang-Hyun;Kim, Su-Nam;Altantsetseg, Shataryn;Shatar, Sanduin;Sarangerel, Oidovsambuu;Nho, Chu-Won
    • Journal of Microbiology
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    • v.45 no.1
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    • pp.53-57
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    • 2007
  • A number of essential oils from Mongolian aromatic plants are claimed to have antimicrobial activities. The essential oil of Dracocephalum foetidum, a popular essential oil used in Mongolian traditional medicine, was examined for its antimicrobial activity. Eight human pathogenic microorganisms including B. subtilis, S. aureus, M. lutens, E. hirae, S. mutans, E. coli, C. albicans, and S. cerevisiae were examined. The essential oil of Dracocephalum foetidum exhibited strong antimicrobial activity against most of the pathogenic bacteria and yeast strains that were tested; by both the agar diffusion method and the minimum inhibitory concentration (MIC) assay ($MIC\;range\;was\;26-2592{\mu}g/ml$). Interestingly, Dracocephalum foetidum even showed antimicrobial activity against methicilin-resistant Staphylococcus aureus (MRSA) strains. We also analyzed the chemical composition of the oil by GC-MS and identified several major components, including n-Mentha-1,8-dien-10-al, limonene, geranial, and neral.