• Title/Summary/Keyword: Inhibition rate

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Inhibition Effects Against Plant Pathogenic Fungi and Plant Growth Promotion by Beneficial Microorganisms (유용 미생물을 활용한 식물 병원 곰팡이의 억제와 식물 생장촉진 효과)

  • Jung, Jin Hee;Kim, Sang Woo;Kim, Yun Seok;Lamsal, Kabir;Lee, Youn Su
    • The Korean Journal of Mycology
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    • v.41 no.2
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    • pp.118-126
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    • 2013
  • The experiment was carried out to analyze the inhibition effect of plant pathogenic fungi and growth promotion activity induced by the bacterial strains isolated from peatmoss. Among the isolated bacterial strains, B10-2, B10-4, B10-5 and B10-6 which showed more than 30% inhibition rate against Botrytis cinerea and Rhizoctonia solani in vitro, were further analyzed in the greenhouse for the growth promotion activity on lettuce (Lactuca sativa), pak-choi (Brassica compestris L. ssp. chinensis) and Chinese cabbage (Brassica campestris L. ssp. pekinensis). The results showed the treatment of B10-4 on lettuce showed the highest growth promotion activity with the leaf area ($169.17cm^2$), fresh weight (leaf: 40.29 g, root: 8.80 g)and dry weight (leaf: 11.24 g, root: 4.17 g), which was about two folds as compared to control. On pak-choi, the growth promotion rate was the highest with the leaf area of $112.87cm^2$, leaf fresh weight of 60.70 g, root fresh weight of 3.37 g, leaf dry weight of 14.34 g, and root dry weight of 1.90 g. As a result of treatment of B10-13 on chinese cabbage, the growth promotion rate was the highest with the leaf area ($293.56cm^2$), fresh weight (leaf: 113.67 g, root: 2.40 g) and dry weight (leaf: 6.03 g, root: 0.53 g). The production of Indole Acetic Acid (IAA) and Indole-3-Butylic Acid (IBA) were also analyzed in these bacterial isolates. The IAA and IBA analyses were carried out in all bacterial isolates each day within the 5 days of incubation period. The highest production of IAA was observed with $112.57{\mu}g/mg$ protein in B10-4 after 3 days of incubation and IBA production was the highest in B10-2 with $58.71{\mu}g/mg$ protein after 2 days of incubation. Also, phosphate solubilizing activity was expressed significantly in B10-13 in comparison to that of other bacterial isolates. Bacterial identification showed that B10-2 was Bacillaceae bacterium and B10-5 was Bacillus cereus, B10-4 and B10-6 were Bacillus sp. and B-13 was Staphylococcus sp. by ITS sequence.

Effects of Ara-C on UV and MMS-induced Excision Repair, Chromosome Aberrations, Sister Chromatid Exchanges and Replication Inhibition (자외선과 MMS에 의한 절제회복, 염색체이상, 자매염색분체 교환 및 복제억제 현상에 미치는 Ara-C의 영향)

  • Park, Kyung-Hee;Park, Sang-Dai
    • The Korean Journal of Zoology
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    • v.23 no.4
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    • pp.203-218
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    • 1980
  • Unscheduled DNA synthesis, chromosome aberrations, sister chromatid exchanges and DNA replication inhibition induced by the combined treatments with ara-C and UV-light or MMS in $HF_1$, CHO and $HelaS_3$ cells were studied, and the results obtained were as follows: (1) Ara-C was found to inhibit UV-or MMS-induced unscheduled DNA synthesis and the inhibitory effect of ara-C was more remarkable in its post-treatment. (2) Ara-C enhanced the rate of chromosome aberrations induced by MMS or UV-light. Post-treatment with ara-C exhibited the synergistic effect on MMS-induced chromosome aberrations mainly by increases of chromatid deletions. (3) Contrarily, ara-C did not increase the rate of sister chromatid exchanges, particularly in the pre-treatment with MMS, although it was found to induce sister chromatid exchanges. (4) The rate of DNA synthesis was declined immediately after are-C treatment and then recovered. The combined treatments with ara-C and UV-light or MMS showed that the initial response on replication inhibition was similar to that of ara-C, but later responses were similar to that of UV-light or MMS treated group.

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Evaluation and Comparison with Standard 48 hr Acute Bioassay and High Temperature Rapid Toxicity Test for Sewage Toxicity Test (하수의 독성평가를 위한 표준독성시험법과 온도증가 단기독성평가법의 비교 평가)

  • Lee, Sang-Ill;Jun, Byong-Hee;Weon, Seung-Yeon;Kim, Yi-Jung;Kim, Keum-Yong
    • Journal of Korean Society of Environmental Engineers
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    • v.27 no.2
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    • pp.191-197
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    • 2005
  • A new method, ToxTemp (TOXcity test based on TEMPerature control) using Ceridaphnia dubia was applied to evaluate the toxicity of insecticide materials and compared with the standard 48 hr acute bioassay. BPMC, diazinon and fenitrothion may cause the inhibition to the biological process in sewage treatment plant and need to detect toxicity within short contact time. The ToxTemp method showed sensitive detection with more shorter contact of 1-1.5 hr time than that of the standard 48 hr acute bioassay. To evaluate toxicity of real wastewater/sewage, the inhibition rate of nitrification and oxygen uptake rate (OUR) using activated sludge, the standard 48hr acute bioassay and ToxTemp method using C. dubia were compared, respectively. On the basis of the inhibition rate of nitrification, the OUR test showed the less sensitive results at the relatively strong toxic sewage. On the other hands, the standard 48hr acute bioassay and ToxTemp method using C. dubia represented the toxicity of each wastewater/sewage with high sensitivity. Even the slightly low (about 1.5%) sensitivity, the ToxTemp method showed the high applicability to the real site of sewage treatment plant.

Observation of the Incidence of Acrosome Reaction in Human Spermatozoa Treated with Mibefradil as a T-type $Ca^{2+}i$ Channels Inhibitor (T-형 $Ca^{2+}$ 채널 길항제인 Mibefradil을 첨가한 인간 정자의 첨체반응 관찰)

  • Lee, Jae-Ho;Son, Weon-Young;Lee, Jung-Ha;Lee, In-Sun;Kim, Young-Chan;Han, Ching-Tack
    • Clinical and Experimental Reproductive Medicine
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    • v.27 no.1
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    • pp.9-14
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    • 2000
  • Objective: The sperm acrosome reaction is a $Ca^{2+}$-dependent exocytotic event that is triggered by adhesion to the mammalian egg's zona pellucida. Previous studies suggested a role of $Ca^{2+}$ channels in acrosome reactions. This study was conducted to investigate the T-type calcium channel is operated in acrosome reaction of human spermatozoa. Method: Human semen samples were obtained from healthy donors with normal criteria. The spermatozoa were divided into five groups: Group 1 were non-treated as a control; Group 2 where spermatozoa were exposed to 5 ${\mu}M$ $Ca^{2+}$ A23187 $(Ca^{2+}i)$; Group 3 where spermatozoa were exposed 5 ${\mu}M$ $Ca^{2+}i$ and mibefradil; Group 4 where spermatozoa were exposed 5 ${\mu}M$ $Ca^{2+}i$ and nifedipine, and Group 5 where spermatozoa were treated with 5 ${\mu}M$ $Ca^{2+}i$ and both of mibefradil and nifedipine. Spermatozoa in all groups were retrieved after incubation for 15 and 30 minutes at $37^{\circ}C$. After staining with PSA-FITC, fluorescence was observed under a fluorescence microscope, and AR was evaluated on a total>100 spermatozoa/side. Result and Conclusion: We observed on acrosome reaction inhibition rate in human spermatozoa the various of concentration of mibefradil, nifedipine. Maximum response was noted with 1.0 ${\mu}M$ mibefradil and the decrease of acrosome reaction inhibition rate 45%. Nifedipine in acrosome reaction inhibition rate was only about 25%. The $Ca^{2+}i$-induced AR of spermatozoa was significantly suppressed by mibefradil. Incidence of the suppression was depending on concentration of mibefradil. Results from the present study suggest that the human spermatozoa possess T-type channel. The observation that reversible inhibitor of T channels in male germ cells provides a new mechanism of contraceptive action.

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광합성 미세조류인 Chlorococcum littorale을 이용한 이산화탄소의 생물학적 고정화

  • Kim, Tae-Ho;Sung, Ki-Dong;Lee, Jin-Suck;Lee, Joon-Yeop;Ohh, Sang-Jip;Lee, Hyeon-Yong
    • Microbiology and Biotechnology Letters
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    • v.25 no.3
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    • pp.235-239
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    • 1997
  • Chlorococcum littorale has been grown in high $CO_2$ concentrations to utilize $CO_2$ gas in the polluted air. The effect of incident light intensity on the specific growth rate is expressed by a photoinhibition model, showing half- saturation constant, $K_0\;as\;8\;(W/m^2)$ and inhibition constant, Ki as 35 $(W/m^2)$. The maximum specific growth rate was also estimated as 0.095 (1/day) under this condition. This strain maintained the optimum growth rate in 20% of $CO_2$ gas but 50% of input $CO_2$ gas is the maximum concentration considering the economical efficiency. The maximum Specific $CO_2$ consumption rate, $qCO_2$ was measured as 17.48 (mg $CO_2/g$ dry wt./day) in batch cultivation, 11.2 (mg $CO_2/g$ dry wt./day) in fed-batch cultivation and 10.87 (mg $CO_2/g$ dry wt./day) at 0.065 (1/day) of dilution rate in continuous cultivation. The chemical composition of the biomass obtained from this process showed 32.5% of protein, 27.5% of lipid, 16.5% of carbohydrate and ash 11.7%.

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Effects of Organic Solvents on Mucus Penetration Distance, Motility and Survival Rate of Human Sperm in vitro (수종의 유기용제가 사람 정자의 점액 침투능, 운동성과 생존율에 미치는 영향)

  • Yoo Dong-Chul;Choi Dal-Woong
    • Environmental Analysis Health and Toxicology
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    • v.19 no.2
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    • pp.177-182
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    • 2004
  • Alcohol consumption and exposure to endocrine disruptors and industrial solvents have been implicated in impaired spermatogenesis, increase in the incidence of malformed sperm and decrease in the percentage of moving sperm. The aim of this study was to determine and compare the direct effects of some organic solvents(bisphenol A; BPA, dibutyl phthalate; DBP, formaldehyde; HCHO, dimethylsulphoxide; DMSO, ethanol) on mucus penetration distance, motility and survival rate of human sperm in vitro. Semen samples from 3 health subjects were prepared using swim-up method and 0.0005-0.5% organic solvents were added to the test medium. BPA, DBP, HCHO and DMSO produced significant decreases in the motility and survival rate with a different potency. The most potent inhibition of mucus penetration distance, motility and survival rate was observed after exposure to HCHO. A concentration of 0.0005% HCHO significantly inhibited sperm motility. When ethanol m.: added directly to sperm, at concentrations equivalent to that in serum after heavy drinking, these damaging effects were lowest compared with other solvents. Present study shows that each compound has different toxic potency to human sperm and we need special caution for the use of HCHO.

Prevalence of Serum Antibodies in Breeder Chickens against Specific Avian Pathogens (특정(特定) 전염성(傳染性) 병인체(病因體)에 대한 국내(國內) 종계(種鷄)의 항체(抗體) 보유상황(保有狀況))

  • Kim, Soon J.;Rhee, Young O.;Kim, Sun J.;Jhun, Woo S.;Park, Keun S.
    • Korean Journal of Veterinary Research
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    • v.20 no.1
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    • pp.59-64
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    • 1980
  • Incidence of avian infectious diseases in breeder chickens was followed serologically. Serum samples were collected during the period of 1978~1979 from breeders throughout country and tested for the presence of antibodies against Salmonella pullorum(SP), Mycoplasma gallisepticum(MG), Avian Infectious Bronchitis virus(AIBV), Infectious Bursal Disease virus(IBDV) and Egg Drop Syndrome Virus(EDS). The tests used serum plate agglutination for SP and MG, immuno-diffusion for AIBV and IBDV and hemagglutination-inhibition test for EDS virus. The results are summarized as follows: 1. Individuals and Hocks incidence rate of Avian Infectious Bronchitis virus were 16.9% and 55.3%. 2. Individuals and Hocks incidence rate of Infectious Bursal Disease virus were 50.1% and 66.4%. 3. Individuals and Hocks incidence rate of sal. pullorum were 17.2% and 65.9%. 4. Individuals and flocks incidence rate of M. gallisepticum were 36.2% and 63.2%. 5. Individuals and flocks incidence rate of Egg Drop Syndrome (BC 14) virus were 14.1% and 46.3%.

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Inhibitory action of adenosine on sinus rate in isolated rabbit SA node (토끼 동방결절 박동수에 대한 아데노신의 작용)

  • Chae, Hurn;Suh, Kyung-Phlill;Kim, Ki-Whan
    • Journal of Chest Surgery
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    • v.16 no.2
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    • pp.199-212
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    • 1983
  • The inhibition/influences of adenine compounds on the heart have been described repeatedly by many investigators, since the first report by Druny and Szent-Gyorgyi [1929]. These studies have shown that adenosine and adenine nucleotides have an over-all effect similar to that of acetylcholine [ACh] by slowing and weakening the heartbeat. The basic cellular and membrane events underlying the inhibitory action of adenosine on sinus rate, however, are not well understood. Furthermore, the physiological role of adenosine in regulation of the heartbeat remains still to be elucidated. Therefore, this study was undertaken in order to examine the response of rabbit SA node to adenosine and to compare the response to that of ACh. Isolated SA node preparation, whole atrial pair, or left atrlal strip was used in each experiment. Action potentials of SA node were recorded through the intracellular glass microelectrodes, which were filled with 3M KCI and had resistance of 30-50 M. All experiments were performed in a bicarbonate-buffered Tyrode solution which was aerated with 3% $CO_2-97%$ $O_2$ gas mixture and kept at $35^{\circ}C$. Spontaneous firing rate of SA node at 35C [Mean + SEM, n=16] was 154 + 3.3 beats/min. The parameters of action potentials were: maximum astolic potential [MDP], -731.7mV: overshoot [OS], 9 + 1.4mV; slope of pacemaker potential [SPP], 94 3.0mV/sec.Adenosine suppressed the firing rate of SA node in a dose dependent manner. This inhibitory effect appeared at the concentration of $10^{-6}M$ and was potentiated in parallel with the increase in adenosine concentration. Changes in action potential by adenosine were dose-dependent increase of MDP and decrease of SPP until $10^{-4}$. Above this concentration, however, the amplitude of action potential decreased markedly due to the simultaneous decrease of both MDP and OS. All these effects of adenosine were not affected by pretreatment of atropine [2mg/l] and propranolol [$5{\times}10^{-6}M$]. ACh [$10^{-6}M$] responses on action potential were similar to those of adenosine by increasing MDP and decreasing SPP. These effects of ACh disappeared by pretreatment of atropine [2mg/1]. Inhibition/effects of adenosine and ACh on sinus rate were enhanced synergistically with the simultaneous administration of adenosine and ACh. Marked decrease of overshoot potential was the most prominent feature on action potential. Dipyridamole [DPM], which is known to block the adenosine transport across cell membrane, definitely potentiated the action of adenosine . Adenosine suppressed the sinus rate and atrial contractility in the same dosage range, even in the reserpinized preparation. Above` results suggest that adenosine suppresses pacemaker activity, like ACh, by acting directly on the membrane of SA node, increasing MDP and decreasing SPP.

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Antioxidant and Antiwrinkle Effects of Persimmon Leaves extract (시엽(Persimmon Leaves) 에탄올 추출물의 항산화와 항주름 효과)

  • Sung-Hee Kim;Dong-Hee Kim;Wi-Hye Yeon;Jin-Tae Lee;Young-Ah Jang
    • Journal of the Korean Applied Science and Technology
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    • v.40 no.3
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    • pp.534-546
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    • 2023
  • In this study, we investigated the antioxidant and anti-winkle activity in human fibroblast cell (CCD-986sk) of Persimmon Leaves (PL) as a cosmetic ingredient. As a result of investigating antioxidant activity through electron-donating ability and ABTS+ radical scavenging assay, the PL showed concentration-dependent antioxidant activity similar to ascorbic acid, a control group, at a concentration of 1,000 ㎍/ml. As a result of investigating the anti-wrinkle effect through elastase inhibition and collagenase inhibition assay, the PL showed concentration-dependent antioxidant activity similar to epigallocatechin gallate, a control group, at a concentration of 1,000 ㎍/ml. As a result of measuring the synthesis rate of pro-collagen type I and the inhibition rate of MMP-1 in UVB-induced CCD-986sk cells, the control group EGCG showed a 90.2% pro-collagen synthesis rate at 20 ㎍/ml and PL showed an 88.5% synthesis rate at 30 ㎍/ml. In addition, the inhibition rate of MMP-1 of 33.0% and 40.8% were confirmed in EGCG 20 ㎍/ml and PL 30 ㎍/ml, respectively. As a result of measuring the protein expression of pro-collagen type I and MMP-1 in the PL through western blot, it was confirmed that the protein expression of pro-collagen type I increased, and MMP-1 decreased when the PL was treated together compared to the UVB alone group. According to the above experimental results, it is expected to be used as a natural product material for cosmetics by confirming that the PL prevent photoaging caused by UVB stimulation and have antioxidant and anti-wrinkle effects.

길항미생물 Pseudomonas sp. GRC3의 식물병원균에 대한 항균력

  • O, Ji-Hun;Park, Sin;Gang, Seon-Cheol
    • 한국생물공학회:학술대회논문집
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    • 2001.11a
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    • pp.660-661
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    • 2001
  • Pseudomonas sp. GRC3 produced extracellular chitinase(s) and ${\beta}$-1,3-glucanase(s), possible biocontrol agents. Both of enzymes appeared to inhibit the growth of plant phathogens, especially Phytophthora capsici. Antifungal activities of Pseudomonas sp. GRC3 determined was more than 78% inhibition rate against P. capsici.

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