• Title/Summary/Keyword: growth-inhibiting

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Purification and Characterization of an Antibacterial Substance from Aerococcus urinaeequi Strain HS36

  • Sung, Ho Sun;Jo, Youl-Lae
    • Journal of Microbiology and Biotechnology
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    • v.30 no.1
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    • pp.93-100
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    • 2020
  • A bacterial strain inhibiting the growth of Vibrio anguillarum, the causative agent of vibriosis, was isolated from fish intestines. The isolated strain HS36 was identified as Aerococcus urinaeequi based on the characteristics of the genus according to Bergey's Manual of Systematic Bacteriology and by 16S rRNA sequencing. The growth rate and antibacterial activity of strain HS36 in shaking culture were higher than those in static culture, while the optimal pH and temperature for antibacterial activity were 7.0 and 30℃, respectively. The active antibacterial substance was purified from a culture broth of A. urinaeequi HS36 by Sephadex G-75 gel chromatography, Sephadex G-25 gel chromatography, and reverse-phase high-performance liquid chromatography. Its molecular weight, as estimated by Tricine SDS-polyacrylamide gel electrophoresis, was approximately 1,000 Da. The antibacterial substance produced by strain HS36 was stable after incubation for 1 h at 100℃. Although its antibacterial activity was optimal at pH 6-8, activity was retained at a pH range from 2 to 11. The purified antibacterial substance was inactivated by proteinase K, papain, and β-amylase treatment. The newly purified antibacterial substance, classified as a class II bacteriocin, inhibited the growth of Klebsiella pneumoniae, Salmonella enterica, and Vibrio alginolyticus.

Growth, Structure, and Stability of Ag on Ordered ZrO2(111) Films

  • Han, Yong;Zhu, Junfa;Kim, Ki-jeong;Kim, Bongsoo
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.204.2-204.2
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    • 2014
  • Among various metal oxides, ZrO2 is of particular interests and has received widespread attention thanks to its ideal mechanical and chemical stability. As a cheap metal, Ag nanoparticles are also widely used as catalysts in ethylene epoxidation and methanol oxidation. However, the nature of Ag-ZrO2 interfaces is still unknown. In this work, the growth, interfacial interaction and thermal stability of Ag nanoparticles on ZrO2(111) film surfaces were studied by low-energy electron diffraction (LEED), synchrotron radiation photoemission spectroscopy (SRPES), and X-ray photoelectron spectroscopy (XPS). The ZrO2(111) films were epitaxially grown on Pt(111). Three-dimensional (3D) growth model of Ag on the ZrO2(111) surface at 300 K was observed with a density of ${\sim}2.0{\times}1012particles/cm2$. The binding energy of Ag 3d shifts to low BE from very low to high Ag coverages by 0.5 eV. The Auger parameters shows the primary contribution to the Ag core level BE shift is final state effect, indicating a very weak interaction between Ag clusters and ZrO2(111) film. Thermal stability experiments demonstrate that Ag particles underwent serious sintering before they desorb from the zirconia film surface. In addition, large Ag particles have stronger ability of inhibiting sintering.

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Effects of Stem Extracts from Perilla and Buckwheat on Seed Germination and Seedling Growth of Barnyard grass and Chinese Cabbage (들깨 및 메밀의 건경추출액이 피와 배추의 발아 및 초기생장에 미치는 영향)

  • 성낙술;한의동;우연수
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.32 no.4
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    • pp.443-446
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    • 1987
  • The present study was conducted to investigate the effects of stem extracts from perilla and buckwheat on the germination and seedling growth of barnyard grass and chinese cabbage. The major results obtained are as follows. The stem extracts showed inhibiting effects on seed germination. The degree of inhibition was much higher with the extracts of perilla than those of buckwheat and more sensitive to chinese cabbage than barnyard grass. The trends of inhibition effects on seedling growth were the same as in the seed germination with lower degree. The roots were more sensitive to the extracts than the tops with higher degree with buckwheat extracts.

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The Effect of Fungicides on Mycelial Growth and Conidial Germination of the Ginseng Root Rot Fungus, Cylindrocarpon destructans

  • Shin, Jong-Hwan;Fu, Teng;Park, Kyeong Hun;Kim, Kyoung Su
    • Mycobiology
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    • v.45 no.3
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    • pp.220-225
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    • 2017
  • Ginseng root rot caused by Cylindrocarpon destructans is the most destructive disease of ginseng. Six different fungicides (thiophanate-methyl, benomyl, prochloraz, mancozeb, azoxystrobin, and iprodione) were selected to evaluate the inhibitory effect on the mycelial growth and conidial germination of C. destructans isolates. Benomyl and prochloraz were found to be the most effective fungicides in inhibiting mycelial growth of all tested isolates, showing 64.7% to 100% inhibition at a concentration of $10{\mu}g/mL$, whereas thiophanate-methyl was the least effective fungicide, showing less than 50% inhibition even at a higher concentration of $100{\mu}g/mL$. The tested fungicides exhibited less than 20% inhibition of conidium germination at concentrations of 0.01, 0.1, and $1{\mu}g/mL$. However, the inhibition effect of mancozeb on condium germination of C. destructans was significantly increased to 92% to 99% at a higher concentration of $100{\mu}g/mL$, while the others still showed no higher than 30% inhibition.

New Safrole Oxide Derivatives: Synthesis and in vitro Antiproliferative Activities on A549 Human Lung Cancer Cells

  • Wang, Li-Ying;Wang, Xiu-Hua;Tan, Jia-Lian;Xia, Shuai;Sun, Heng-Zhi;Shi, Jin-Wen;Jiang, Ming-Dong;Fang, Liang;Zuo, Hua;Dupati, Gautam;Jang, Kiwan;Shin, Dong-Soo
    • Bulletin of the Korean Chemical Society
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    • v.33 no.11
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    • pp.3571-3575
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    • 2012
  • A number of novel small molecules, safrole oxide derivatives 4a-c, 6a-c, 9a-h, were synthesized by the reaction of safrole oxide with anilines 3 and 5, or its alkyl allyl ether derivative 7 with alkyl bromide 8 in moderate yields. The antiproliferative effects of all the target molecules on A549 cell growth were investigated and it was found that the 14 novel compounds could suppress A549 lung cancer cell growth. Among them, compound 6b was the most effective compound in inhibiting the proliferation of A549 cells.

Effect of Calcium Cyanamide Soil Fumigation on Sterilization of Rhizoctonia solani, Pythium sp., Soil Microbes and Plant Seed (석회질소 토양훈증의 라이족토니아 소라니, 피시움, 토양미생물과 씨앗의 사멸효과)

  • Lee, Byung-Dae;Park, Roan
    • Journal of Ginseng Research
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    • v.33 no.2
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    • pp.139-142
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    • 2009
  • The effect of calcium cyanamide (China-made) soil fumigation on the growth of the ginseng pathogen Rhizoctonia, Pythium), soil microbes, and seed germination of lettuce and radish was investigated. At twice the recommended level (2S0-ppm $CaCN_2$), the growth of Rhizoctonia and Pythium, and the seed germination, were not inhibited. Rather, the effective level was 10,000 ppm. The powder form was more effective than the granular form in inhibiting pathogen growth and seed germination. The lettuce seed was also more sensitive than the radish seed. Calcium cyanamide appearedto decrease the fungi population and to increase Actinomycetes in the soil.

Effects of Electrodeposition condition on the fracture characteristics of 80Sn-20Pb electrodeposits aged at 15$0^{\circ}C$ (15$0^{\circ}C$에서 시효처리한 80Sn-20Pb 합금 도금층의 파괴특성에 전착조건이 미치는 영향)

  • 김정한;서민석;권혁상
    • Journal of Surface Science and Engineering
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    • v.27 no.5
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    • pp.292-302
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    • 1994
  • Alloy deposits of 80Sn-20Pb, electroplated on Cu-based leadframe alloy from an organic sulfonate bath were aged at $150^{\circ}C$ to form intermetallic phases between substrate and deposit, and effects of the deposit morphology, influenced by deposition conditions, on the fracture resistance of the 80Sn-20Pb deposit aged at $150^{\circ}C$ were examined. The growth rate of intermetallic compound layer on aging depended on the microstructure of deposit ; it was fastest in deposit formed using pulse current in bath without grain refining additive, but slowest in deposit formed using dc current in bath containing grain refining additive in spite of similar structure with equivalent grain size. The grain refining additive incorporated in electrodeposit appears to inhibit diffusion of atoms on aging, resulting in slow growth of intermetallic layer in the thickness direction but substantial growth in the lateral one. Density of surface cracks that were occurring when samples were subjected to the $90^{\circ}$-bending test increased with increasing the thickness of intermatallic layer on aging. For the same aged samples, the surface crack density of the sample electrodeposited from a bath containing the grain refining additive was the least due to the inhibiting effect of the additive incorporated into the deposit during electrolysis on atomic diffusion.

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Growth and Chlorophyll Biosynthesis of Vigna angularis under Lead Stress

  • Suh-Young Koo;Sun
    • Journal of Environmental Science International
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    • v.1 no.2
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    • pp.145-155
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    • 1992
  • The effect of various supplies of lead singly and in combination with aluminium on growth and chlorophyll biosynthesis was investigated in 7-day-old Vigna anguluris seedlings. Expose to 50 $\mu$N Pb or more drastically reduced root elongation rate. Significant depressions in root growth was observed within 1 day and no recovery of growth was seen over the duration of treatment period. Root elongation decreased depending on the Pb concentrations. Root growth inhibition was stronger than shoot growth inhibition. The initiation of lateral roots appeared to be more sensitive to Pb than the growth of main roots. Inhibition of root and shoot elongation by Pb was lessened by combined exposure of Pb and Al, suggesting that the presence of AA reverse the inhibitory effect of Pb alone. With the histochemical sodium rhodizonate method the rate of Pb uptake was dependent on the Pb concentration and exposure time of the roots to Pb salts. Pb was first deposited on the root surface and then translocated radially in the root cap cells. During a longer Pb administration (up to 72 h) Pb penetration was nonuniform, with accumulation within the cortex or endodermis. There was drastic reduction in chlorophyll content by Pb. The Pb inhibition of chlorophyll synthesis was concentration dependent. 5-Aminolevulinic acid dehydratase (ALAD) activity exhibited distinct inhibition from control. Reduction in chlorophyll content was accompanied by proportional changes in ALAD activity. Chlorophyll content and ALAD activity were less affected by combined exposure of Pb and Al, suggesting that Al has a protective effect against the inhibiting action of Pb on photosynthetic activity.

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Inhibition of Oral Epithelial Cell Growth in vitro by Epigallocatechin-3-gallate; Its Modulation by Serum and Antioxidant Enzymes

  • Hong, Jung-Il;Kim, Mi-Ri;Lee, Na-Hyun;Lee, Bo-Hyun
    • Food Science and Biotechnology
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    • v.18 no.4
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    • pp.971-977
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    • 2009
  • The most abundant tea catechin, epigallocatechin-3-gallate (EGCG), has been reported to inhibit cell proliferation and induce apoptosis in many types of cancer cells. In the present study, effects of EGCG on the growth of oral epithelial cells including CAL-27 oral squamous carcinoma cells and dysplastic oral keratinocytes (DOK) were investigated. EGCG inhibited growth of CAL-27 cells and DOK with $IC_{50}$ of 14.4-21.0 and 5.8-14.2 ${\mu}M$ after 24 and 48 hr incubation, respectively. EGCG was significantly less effective in inhibiting DOK growth. The effects of EGCG, however, were dramatically less pronounced in the presence of superoxide dismutase (SOD) and catalase. Inhibitory effects of EGCG on CAL-27 cell growth were also much less pronounced in the presence of fetal bovine serum (FBS). EGCG induced caspase-3 activation in both CAL-27 and DOK cells in a serum free condition without SOD/catalase; in the presence of 10% FBS and SOD/catalase, EGCG, even at 100 ${\mu}M$, did not affect cell growth. The present results indicate that EGCG inhibited oral cell growth with higher potency to more malignant CAL-27 cells than DOK, and the effects were markedly altered by SOD/catalase and serum content in media.

Growth and Chlorophyiil Biosynthesis of Vigna angularis under Lead Stress

  • Koo Suh-Young;Jin Sun-Young;Hong Jung-Hee
    • Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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    • v.1 no.2
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    • pp.145-155
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    • 1997
  • The effect of various supplies of lead singly and in combination with aluminium on growth and chlorophyll biosynthesis was investigated in 7-day-old Vigna angularis seedlings. Expose to 50 uM Pb or more drastically reduced root elongation rate. Significant depressions in root growth was observed within 1 day and no recovery of growth was seen over the duration of treatment period. Root elongation decreased depending on the Pb concentrations. Root growth inhibition was stronger than shoot growth inhibition. The initiation of lateral roots appeared to be more sensitive to Pb than the growth of main roots. Inhibition of root and shoot elongation by Pb was lessened by combined exposure of Pb and Al, suggesting that the presence of Al reverse the inhibitory effect of Pb alone. With the histochemical sodium rhodizonate method the rate of Pb uptake was dependent on the Pb concentration and exposure time of the roots to Pb salts. Pb was first deposited on the root surface and then translocated radially in the root cap cells. During a longer Pb administration (up to 72 h) Pb penetration was nonuniform, with accumulation within the cortex or endodermis. There was drastic reduction in chlorophyll content by Pb. The Pb inhibition of chlorophyll synthesis was concentration dependent. $\delta-Aminolevulinic$ acid dehydratase (ALAD) activity exhibited distinct inhibition from control. Reduction in chlorophyll content was accompanied by proportional changes in ALAD activity. Chlorophyll content and ALAD activity were less affected by combined exposure of Pb and Al, suggesting that Al has a protective effect against the inhibiting action of Pb on photosynthetic activity.

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