• Title/Summary/Keyword: Inhibitory Effect

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Research to Fungicide Sensitivity of Colletotrichum spp. Isolated from Apple Fruits in Cheongsong, Korea (사과 주 재배지 경북 청송 지역 사과 탄저병원균의 살균제에 대한 감수성 조사)

  • Jungyeon Kim;Heung Tae Kim;Yongho Jeon
    • Research in Plant Disease
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    • v.29 no.2
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    • pp.145-157
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    • 2023
  • Apple grower in the Cheongsong region, Korea has reported the increased loss of apple yield due to severe bitter rot incidence. We noticed that this indience is because the Colletotrichum population has developed resistance to commonly used fungicides. We isolated 39 Colletotrichum isolates from 13 orchards in Cheongsong, and all the isolated Colletotrichum species were identified as C. siamense or C. fructicola. These 39 strains were tested for mycelial growth and conidial germination against 12 fungicides. trifloxystrobin (30-55% in recommended concentrations) was shown lower inhibitory effect on mycelial growth. However, the inhibition of conidial germination was shown higher than mycelial growth (62-100%). Kresoxim-methyl was shown lower inhibitory effect on mycelial growth (29-55%). conidial germination inhibitory effect was shown 51% to 96%. dithianon was shown diversity response to inhibition of mycelial growth (43-100%). Tebuconazole was shown high inhibitory effect on mycelial growth (84-100%) and conidial germination inhibitory effect was shown to be 64 to 100%. metconazole has been found to display with high inhibitory effect on mycelial growth (79-100%) and conidial germination (70-80%). fluazinam was shown to possess high inhibitory effect on mycelial growth (87-100%) and conidial germination (94-100%). This study provides basic information for the effective management of apple bitter rot.

Colony Count with Mixed Culture of Enteric Bacteria by in vitro Quantitative Method (장내세균의 시간차 혼합배양이 보여주는 균수측정의 비교)

  • 황선철;전보성
    • Korean Journal of Microbiology
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    • v.11 no.4
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    • pp.175-180
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    • 1973
  • This study was attempted to see more clear relationships among the enterobacteria, especially between the intestinal normal flora and pathogenic bacteria. It has been known that some intestinal normal flora produce the bactrial metabolites that are harmful to other enteric bacteria. One of the metabolites is known as colicin, the protein fraction, which possesses certain degree of inhibitory effect against other bacterial growth fraction, whih possesses certain degree of inhibitory effect against other bacterial growth. As a preliminary study for a colicin purification, the antagonistic effect of E, coli to groups of Salmonella and Shigella has been studied by means of in vitro quantitative culture method. 1. E.coli showed definite inhibitory effects aganist both Salmonella and Shigella groups in the mixture of two organisms. 2. The inhibitory effects of E.coli in the E.coli-Salmonella and the E.coli-Shigella mixture occurred from 4 hours incubation following the inoculation. 3. Even the complete inhibition of pathogenic enteric bacterial growth was noticed in the E.coli-Salmonella mixture at overnight incubation. 4. Among the diluted mixtures, 1:100, 1:1,000, and 1:10,000, survival rate of pathogenic enteric bacteria in the mixtures with E.coli showed least affected at the 1:1,000 dilution. 5. It was found that the antagonistic effect aganist groups of Salmonella-shigella was depending upon the groups of the genera.

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Inhibitory Effect of Sorbus cortex Extract on (1,3)-$\beta$-Glucan Synthase (정공피 추출물의 (1,3)$\beta$-Glucan Synthase에 대한 억제효과)

  • You, Myung-Ja;Kim, Bo-Mi;Lee, Jeong-Ho;Lee, Young-Hang;Chai, Kyu-Yun;Baek, Seung-Hwa
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.22 no.5
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    • pp.1196-1201
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    • 2008
  • A examination of the kinetic properties of UDP-glucose : (1,3)-$\beta$-glucan (callose) synthase from mung bean seedings (Sorbus cortex) shows that these enzymes have a complex interaction with UDP-glucose and various effectors. Deoxynojirimycin increased the inhibitory effect of (1,3)-$\beta$-glucan synthase at the concentration-dependent manner by fluorescence assay. The inhibitory effect of Fr. 2-16 (97.15%) showed higher than that of deoxynojirimycin (80.63%). Fr. 2-3 inhibited the growth of the Candida albicans at 1 mm inhibition zone by disk diffusion method. These results suggest that Sorbus cortex extract can be used as a stable antifungal material.

Inhibitory Effect of Pine Needle(Pinus densiflora S.) Extract on Potato Polyphenol Oxidase (감자 polyphenol oxidase에 대한 솔잎 추출물의 저해효과)

  • Lee, Min-Kyung
    • Journal of Life Science
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    • v.16 no.5
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    • pp.866-869
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    • 2006
  • The inhibitory effect of pine needle (Pinus densiflora S.) on potato polyphenol oxidase (PPO) was investigated. The addition of the pine needle extract exhibited a higher inhibitory effect on the potato polyphenol oxidase activity than that of the citric acid or potassium sorbate. The enzyme activity was strongly inhibited in a pH range of 7.0-8.0. When the incubation time of reaction mixture was increased, the potato polyphenol oxidase activity was markedly inhibited. The pine needle extract inhibited the potato polyphenol oxidase non-competitively. And also the pine needle extract subjected to a heat treatment at $100^{\circ}C$ for 10 min or to an acid treatment at pH 2.0, 3.0, and 4.0 for 3 hours still retained inhibitory effect on potato polyphenol oxidase.

Inhibitory Effect and Mechanism on Melanogenesis of Radix glycyrrhizae Water Extract (감초 물추출물의 멜라닌 형성 억제효과 및 기전에 관한 연구)

  • Kim, Jin;Kwen, Il-ho;Lim, Hong-jin;Lim, Kyu-sang;Hwang, Chung-yeon
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.16 no.2
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    • pp.96-118
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    • 2003
  • The effect of Glycyrrhizae Radix water extract, known as depigmenting agent, on melanin biosynthesis was investigated in cellular level by using B16 mouse melanoma cells. The inhibitory effect of Glycyrrhizae Radix water extract on melanogenesis was determined by mushroom tyrosinase assay traditionally using in vitro screening test. To determine whether Glycyrrhizae Radix water extract suppress melanin synthesis in cellular level, B16 mouse melanoma cells were cultured in the presence of different concentrations of Glycyrrhizae Radix water extract. Effects on cell proliferation, melanin biosynthesis, tyrosinase activity, DOPAchrome tautomerase activity, and expression level of mRNA for tyrosinase were examined. The maximum concentration of Glycyrrhizae Radix water extract that was not inhibitory to growth of the cells was 2 mgml. At that concentration, melanin synthesis was significantly inhibited without cytotoxicity after 5 days, compared with untreated cells. The treatment with Glycyrrhizae Radix water extract reduced tyrosinase and DOPAchrome tautomerase activity in a dose-dependent manner. However, the treatment with Glycyrrhizae Radix water extract did not affect significantly mRNA levels for tyrosinase. These results suggest that the inhibitory effect of Glycyrrhizae Radix water extract on melanogenesis is correlated with the suppression of tyrosinase and DOPAchrome tautomerase activity more than altering mRNA levels of tyrosinase.

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Monoamine Oxidase Inhibitors Attenuate Cytotoxicity of 1-Methyl-4-phenylpyridinium by Suppressing Mitochondrial Permeability Transition

  • Lee, Chung-Soo
    • The Korean Journal of Physiology and Pharmacology
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    • v.10 no.4
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    • pp.207-212
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    • 2006
  • Mitochondrial permeability transition has been shown to be involved in neuronal cell death. Mitochondrial monoamine oxidase (MAO)-B is considered to play a part in the progress of nigrostriatal cell death. The present study examined the effect of MAO inhibitors against the toxicity of 1-methyl-4-phenylpyridinium $(MPP^+)$ in relation to the mitochondrial permeability transition. Chlorgyline (a selective inhibitor of MAO-A), deprenyl (a selective inhibitor of MAO-B) and tranylcypromine (nonselective inhibitor of MAO) all prevented cell viability loss, cytochrome c release, caspase-3 activation, formation of reactive oxygen species and depletion of GSH in differentiated PC12 cells treated with $500\;{\mu}M$$MPP^+$. The MAO inhibitors at $10\;{\mu}M$ revealed a maximal inhibitory effect and beyond this concentration the inhibitory effect declined. On the basis of concentration, the inhibitory potency was tranylcypromine, deprenyl and chlorgyline order. The results suggest that chlorgyline, deprenyl and tranylcypromine attenuate the toxicity of $MPP^+$ against PC12 cells by suppressing the mitochondrial permeability transition that seems to be mediated by oxidative stress.

An Experimental Studies on the Effects of Chunggisan (淸肌散의 效能에 關한 實驗的 硏究)

  • Kim, Hye-Jeong;Chae, Byeong-Yun
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.3 no.1
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    • pp.25-40
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    • 1990
  • Chunggisan has been widely used in treatment of urticaria which is based on. Oriental Medical literatures. These studies were attempted experimental effects of chunggisan on the analgesia, sedation, antipyretic, anti-inflammatory and isolated illeum of the experimental animals. The result of the studies were as follows: 1. The inhibitory effect was recognized on the Analgesic study by the Acetic acid Method in mice. 2. The spontaneous momentum of mice was restricted and the duration of Hypnosis induced by pentobarbital-sodium in mice was prolonged. 3. Anti-inflammatory effect was recognized significantly on the rat hind paws edema induced by dextran. 4. The inhibitory effect of leukocyte emigration was recognized by the CMC airpouch method of rats. 5. The inhibitory effect was noted on capillary permeability induced by histamin in mice. 6. Spontaneous mobilities in isolated ileum of mice were significantly suppressed, and contraction by acetylcholine, barium chloride and histamine were inhibited. According to the above results, it is expected that chunggisan can be widely used in treatment of urticaria.

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Inhibitory Effect of the Root of Coptis japonica on Catecholamine Biosynthesis in PC12 Cells

  • Lee, Myung-Koo;Park, Woo-Kyu;Kim, Hack-Seang
    • Archives of Pharmacal Research
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    • v.17 no.4
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    • pp.269-272
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    • 1994
  • The effect of the root of Coptis japonica (COPT), both dichloromethane soluble $(CH_2Cl_2)$ and insoluble $(H_2O)$ fractions, on catecholamine contents and tyrosine hydorxylase (TH) activity in PC12 cells was investigated. $(CH_2Cl_2){\;}and{\;}H_2O$ fractions showed 21 and 53% inhibitions on dopamine content, respectively, at a ocncentraction of 40 .mu.g/ml in medium : the $(H_2O)$ fraction proveided a grateer inhibitory effect. The TH activity was reduced by the treatment of COPT ($(H_2O)$ fraction). These results suggest that COPT has an inhibitory effect on the catecholamine biosynthesis by the reduction of TH activity in PC12 cells.

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Effects of Ginkgo biloba Extract (EGb 761) on the Enalapril-induced ACE Inhibition in SHRs (SHR에 있어 Enalapril의 ACE억제효과에 대한 Ginkgo biloba Extract(EGb 761)의 영향)

  • 이영미;염윤기;신완균;손의동;안형수
    • YAKHAK HOEJI
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    • v.45 no.1
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    • pp.93-100
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    • 2001
  • Drug inetraction between of enalapril-induced angiotensin converting enzym) inhibitory effect and Ginkgo biloba Ext.-induced antioxidant action was evaluated in spontaneously hypertensive rats. Combination treatment of enalapril (20 mg/kg/day p.o.) and Ginkgo biloba Ext. (60 mg/kg/day, p.o.) for 6 weeks in drinking water to SHRs resulted the inhibition of ACE activity in lung tissue, angiotensin I-induced pressure response and plasma angiotensin II concentration as similar to enalapril alone treatment. But these effects were sustained after 1 week withdrawal of enalapril and Ginkgo biloba Ext. co-administeration. Also, coadministered group did not increase the concentration of bradykinin in lung tissue, which were different from enalapril alone treated group. Co-administration of enalapril and Ginkgo biloba Ext. inhibited the hemolysis induced by UV B type, even Ginkgo biloba Ext. alone treated group did not. These results suggested that Ginkgo biloba Ext. sustained ACE inhibitory effect and reduced the inhibitory effect of bradykinin inactivation induced by enalapril, meanwhile, enalapril increased the antioxidant effect of Ginkgo biloba Ext.

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Effect of Ethanol on Histamine Release from Rat Peritoneal Mast Cells (Ethanol이 휜쥐의 복강비만세포에서 Histamine유리에 미치는 영향)

  • 김찬종;이윤혜;이승준;서무현;장용운
    • YAKHAK HOEJI
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    • v.45 no.6
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    • pp.677-682
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    • 2001
  • investigate action of ethanol on histamine release from rat peritoneal mast cells, we compared the inhibitory effect of ethanol with those of calcium antagonists in mechanism of between ATP and compound 48/80-induced histamine release. Ethanol dose-dependently inhibited 100 ${\mu}{\textrm}{m}$ ATP-induced histamine release, whereas did not inhibit 1 $\mu\textrm{g}$/ml compound 48/80-induced histamine release. Verapamil, TMB-8 and EGTA dose-dependently inhibited ATP-induced histamine release, but did not inhibit compound 48/80-induced histamine release. Such an inhibitory effect of calcium antagonist was similar to that of ethanol. These results suggest that the inhibitory effect of ethanol on histamine release from rat peritoneal mast cells is mediated via disturbance of calcium mobilization..

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