• 제목/요약/키워드: Inhibition zone

검색결과 421건 처리시간 0.022초

In Vitro Antagonistic Effects of Bacilli Isolates against Four Soilborne Plant Pathogenic Fungi

  • Kim, Wan-Gyu;Weon, Hang-Yeon;Lee, Sang-Yeob
    • The Plant Pathology Journal
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    • 제24권1호
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    • pp.52-57
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    • 2008
  • Twenty isolates of Bacillus spp. obtained from livestock manure composts and cotton-waste composts were tested for in vitro antagonistic effects against soilborne plant pathogenic fungi, Fusarium oxysporum, Phytophthora capsici, Rhizoctonia solani AG-4, and Sclerotinia sclerotiorum. Seven isolates of Bacillus spp. had antagonistic effects on mycelial growth of all the isolates of F. oxysporum tested. The bacterial isolate RM43 was the most effective to inhibit the mycelial growth of the fungal isolates. Twelve isolates of Bacillus spp. had antagonistic effects on mycelial growth of all the isolates of P. capsici tested. The bacterial isolates M34 and M47 were very effective to inhibit the mycelial growth of the fungal isolates. Thirteen isolates of Bacillus spp. had antagonistic effects on mycelial growth of all the isolates of R. solani AG-4 tested. The bacterial isolates M27 and M75 were very effective to inhibit the mycelial growth of the fungal isolates. Fourteen isolates of Bacillus sp. had antagonistic effects on mycelial growth of all the isolates of S. sclerotiorum tested. The bacterial isolates M49 and M75 were very effective to inhibit the mycelial growth of the fungal isolates. The antagonistic effects of most Bacillus spp. isolates against the isolates of the four fungi differed depending on the fungal species and the isolates of each fungus. The bacterial isolates M27 and M75 were the most effective to inhibit the mycelial growth of all four fungi.

쇠비름 추출물의 항산화 효과 및 Helicobacterpylori에 대한 항균 활성 (The Antioxidant Effect of Portulaca oleracea Extracts and Its Antimicrobial Activity on Helicobacter pylori)

  • 박소해;김대광;배지현
    • 한국식품영양학회지
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    • 제24권3호
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    • pp.306-311
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    • 2011
  • 본 연구에서는 쇠비름 추출물의 항산화 효과 및 위궤양 유발 병원균으로 잘 알려진 Helicobacter pylori에 대한 항균 효과를 알아보고자 하였다. 쇠비름의 유기용매 추출물의 항산화 효과는 총 페놀 함량, 전자공여능, SOD 유사활성, TBARS 등을 통하여 검증하였다. 쇠비름의 총 페놀 함량은 약탕기 추출물에서 72.2 mg%로 가장 높게 나타났고, 전자공여능은 ethyl acetate 분획물이 91.8%와 methanol 분획물이 90.6%로 나타났다. SOD 유사활성은 2.5 mg/$m{\ell}$의 농도에서 ethyl acetate 분획물 17.4%와 petroleum ether 분획물 16.4%로 높게 나타났다. 쇠비름의 TBARS에 의한 항산화 효과는 유의적으로 나타나지 않았다. Paper disc 법에 의한 Helicobacter pylori 항균 활성의 경우, 쇠비름 추출물의 농도가 증가할수록 inhibition zone 크기가 증가하였고, 쇠비름의 petroleum ether 분획물 10,000 ppm 농도에서 가장 큰 활성이 나타났다.

현호색(玄胡索)과 초초현호색(醋炒玄胡索)의 여드름균에 대한 항균효과 비교 (Comparison of Antimicrobial effects of Corydalis tuber and processed Corydalis tuber against Propionibacterium acnes)

  • 이종록;박숙자;김영우;조일제;변성희;김상찬
    • 한방안이비인후피부과학회지
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    • 제24권3호
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    • pp.17-26
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    • 2011
  • Objectives : Corydalis tuber has been used for promoting blood circulation and for relieving pain in Oriental medicine. In the present study, we focused on the antimicrobial activity of Corydalis tuber and compared its antimicrobial activity with the processed Corydalis tuber. Methods : Processing of Corydalis tuber was accomplished by immersing in 5% of acetic acid for 12 h and then by roasting at $250^{\circ}C$ for indicated time periods(0-30 min). Minimum inhibitory concentration(MIC) and the zone of growth inhibition were determined against Propionibacterium acnes(P. acnes). Results : The methanolic extracts of Corydalis tuber showed potent antimicrobial effect(MIC 62.5 ${\mu}g/ml$). Its alkaloidal component, dehydrocorydaline, also exhibited antibacterial activity(MIC 25.0 ${\mu}g/ml$). After processing of Corydalis tuber, its inhibitory effect on the growth of P. acnes was significantly enhanced compared with that of unprocessed Corydalis tuber. Furthermore, elevated content of dehydrocorydaline was found in the processed than the unprocessed Corydalis tuber. However, the different roasting minutes effected on antimicrobial activity. The best roasting time of Corydalis tuber was 10 min, while roasting for the time above 15 min resulted in diminishing antimicrobial activity. Thus, it was concluded that the standardized processing condition of Corydalis tuber should be established to obtain enhanced antimicrobial(P. acnes) activity. Conclusion : For antimicrobial effect against P. acnes, the best processing condition of Corydalis tuber is immersing in 5% of acetic acid for 12 h and by roasting at $250^{\circ}C$ for 10 min.

식물근권에서 분리한 세균을 처리한 감귤열매에서 감귤 역병 억제 효과 (Suppressive Effect of Bacterial Isolates from Plant Rhizosphere against Late Blight Caused by Phytophthora citrophthora on Citrus Fruits)

  • 강소영;전용철
    • 식물병연구
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    • 제16권1호
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    • pp.35-40
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    • 2010
  • 식물근권에서 유래된 12개의 근권세균이 Phytophthora citrophthora에 의해 발생되는 감귤 역병에 대해 감귤 열매에서 병진전 억제 효과를 나타내는지 조사하였다. 조사한 근권세균 중 THJ609-3, TRH423-3, BRH433-2, Lysochit 및 KRY505-3 등에 의해 역병이 억제되는 것을 역병균의 in vivo 상처접종을 통하여 밝혀졌다. 근권세균을 P.citrophthora의 균사체와 대치 배양하여 역병균 저지대의 길이를 측정한 결과 역병 진전억제효과를 보였던 5개의 균주에서 모두 항진균활성이 나타났다. 그러나 근권세균의 균사생장억제효과와 역병억제효과 사이에 양의 상관관계는 성립되지는 않았다. 한편, 근권세균 rDNA의 internal transcript spaces(ITS)을 분석을 통해 동정 한 결과 Lysochit과 KRY505-3은 Bacillus cereus로 동정 되었고, BRH4332은 B. circulans로, TRH423-3는 Burkholderia gladiol로 동정되었다. 이 연구는 친환경 농가와 같이 농약사용이 제한된 농장에서 감귤 역병에 대해 생물적 방제를 위한 활성균을 모색하는데 매우 가치가 있을 것으로 생각된다.

Decreased Interaction of Raf-1 with Its Negative Regulator Spry2 as a Mechanism for Acquired Drug Resistance

  • Ahn, Jun-Ho;Kim, Yun-Ki;Lee, Michael
    • Biomolecules & Therapeutics
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    • 제19권2호
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    • pp.174-180
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    • 2011
  • Experiments were carried out to determine the role of Raf-1 kinase in the development of drug resistance to paclitaxel in v-H-ras transformed NIH 3T3 fibroblasts (Ras-NIH 3T3). We established a multidrug-resistant cell line (Ras-NIH 3T3/Mdr) from Ras-NIH 3T3 cells by stepwise increases in paclitaxel. Drug sensitivity assays indicated that the $IC_{50}$ value for drug-resistant Ras-NIH 3T3/Mdr cells was more than 1 ${\mu}M$ paclitaxel, 10- or more-fold higher than for the parental Ras-NIH 3T3 cells. Western blot and RT-PCR analysis showed that the drug efflux pump a P-glycoprotein were highly expressed in Ras-NIH 3T3/Mdr cells, while not being detectable in Ras-NIH 3T3 cells. Additionally, verapamil, which appears to inhibit drug efflux by acting as a substrate for P-glycoprotein, completely reversed resistance to paclitaxel in Ras-NIH 3T3/Mdr cell line, indicating that resistance to paclitaxel is associated with overexpression of the multidrug resistance gene. Interestingly, Ras-NIH 3T3/Mdr cells have higher basal Raf-1 activity compared to Ras-NIH 3T3 cells. Unexpectedly, however, the colocalization of Raf-1 and its negative regulator Spry2 was less observed in cytoplasm of Ras-NIH 3T3/Mdr cells due to translocation of Spry2 around the nucleus in the perinuclear zone, implying that Raf-1 may be released from negative feedback inhibition by interacting with Spry2. We also showed that shRNA-mediated knockdown of Raf-1 caused a moderate increase in cell susceptibility to paclitaxel. Thus, the results presented here suggest that a Raf-1-dependent pathway plays an important role in the development of acquired drug-resistance.

Synergistic Effect of Bacteriophage and Antibiotic against Antibiotic-Resistant Salmonella Typhimurium

  • Petsong, Kantiya;Vongkamjan, Kitiya;Ahn, Juhee
    • 한국식품위생안전성학회지
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    • 제35권2호
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    • pp.189-194
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    • 2020
  • 본 연구는 항생제 내성 Salmonella Typhimurium CCARM 8009을 저해하기 위한 phage와 항생제 조합처리의 효과를 평가하였다. 디스크 확산법과 액체배지 희석법에 의해 phage와 항생제의 상승 저해효과를 측정하였고 배양을 통한 항생제 내성 유도를 평가하였다. Phage를 처리한 cefotaxime, chloramphenicol, ciprofloxacin, erythromycin의 디스크의 저해 구역은 각각 13.6%, 19.3%, 12.7%, 78.8%로 증가되었다. Phage와 항생제 조합 처리에 의해 tetracycline, chloramphenicol, ciprofloxacin, erythromycin, streptomycin의 최소생육억제농도는 각각 64, 4, 0.0078, 64, 256 mg/mL으로 감소되었다. Phage와 항생제의 조합 처리는 항생제 내성 S. Typhimurium CCARM 8009을 효과적으로 저해하였다 (4 log reduction). 본 결과는 phage와 항생제의 조합처리는 항생제 내성균을 제어하기 위한 방법으로 충분히 응용가치가 높음을 보여주고 있다.

Antioxidant and antimicrobial activities of different enzymatic hydrolysates from desalted duck egg white

  • Thammasena, Rommanee;Liu, Deng Cheng
    • Asian-Australasian Journal of Animal Sciences
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    • 제33권9호
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    • pp.1487-1496
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    • 2020
  • Objective: The objective of this study was to look for optimal preparation of hydrolysates of desalted duck egg white powder (DDEWP) by the three different proteases and to investigate their antioxidant and antimicrobial properties. Methods: DDEWP was hydrolyzed by three proteases, including pepsin (PEP), Bacillus spp. (BA) and natokinase (NAT) with three different enzyme concentrations (0.1%, 0.3%, and 0.5%), individually. The important key hydrolysis parameters such as hydrolysis degree, yield, antioxidant and antimicrobial activity were evaluated in this experiment. Results: The results showed that the degree of hydrolysis (DH) of all treatments increased with increasing hydrolysis time and protease concentrations. The antioxidant and antimicrobial activities of the hydrolysates were affected by type and concentration of protease as well as hydrolysis time. Hydrolysis of PEP significantly (p<0.05) obtained the highest yield of hydrolysates, however, both of BA and NAT showed substantially lower DH values and still did not exceed 5% by the end of hydrolysis. Among the different hydrolysates, PEP exhibited significantly higher 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity than BA and NAT. All DDEWP hydrolysates from PEP had low ferrous ion chelating activity (<37%) that was significantly lower than that of NAT (>37% to 92%) and BA (30% to 79%). Besides, DDEWP hydrolysates of PEP presented significantly higher reducing power than BA and NAT. In antimicrobial activities, Escherichia coli, Salmonella typhimurium, and Pseudomonas aeruginosa were not effectively inhibited by any DDEWP hydrolysates of PEP except for Staphylococcus aureus. Especially, the excellent antibacterial activity against S. aureus only was displayed in DDEWP hydrolysates of PEP 0.1%. Conclusion: DDEWP hydrolysates from PEP demonstrated significantly better DH, yield, DPPH radical scavenging activity and reducing power, furthermore, had excellent inhibitory on S. aureus due to large clear zone and moderated inhibitory in bactericidal inhibition.

Evaluation on Antimicrobial Activity of Psoraleae semen Extract Controlling the Growth of Gram-Positive Bacteria

  • Kim, Sejeong;Lee, Soomin;Lee, Heeyoung;Ha, Jimyeong;Lee, Jeeyeon;Choi, Yukyung;Oh, Hyemin;Hong, Joonbae;Yoon, Yohan;Choi, Kyoung-Hee
    • 한국축산식품학회지
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    • 제37권4호
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    • pp.502-510
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    • 2017
  • This study investigated bacterial growth-inhibitory effect of 69 therapeutic herbal plants extracts on 9 bacterial strains using a disc diffusion assay. Especially, the antimicrobial activity of Psoraleae semen, which showed different activity on pathogenic Gram-positive and Gram-negative bacteria, was evaluated by MIC (minimal inhibition concentration) and biofilm formation assay. The effect of Psoraleae semen extract on bacterial cell membranes was examined by measurement of protein leakage (optical density at 280 nm) and scanning electron microscope (SEM). No clear zone was formed on discs containing Gram-negative bacteria, but Gram-positive bacteria exhibited clear zones. The MICs of Psoraleae semen extract were $8{\mu}g/mL$ for Streptococcus mutans, and $16{\mu}g/mL$ for Enterococci and Staphylococcus aureus. In addition, biofilm formation was inhibited at concentration $8-16{\mu}g/mL$. Protein leakage values and SEM images revealed that cell membranes of Gram-positive bacteria were impaired following exposure to the extract. Further, the extract inhibited the growth of Listeria monocytogenes in sausages. These results indicate that Psoraleae semen extract could be utilized as a natural antimicrobial agent against Gram-positive bacteria.

Casual Shoe용 피혁의 항균성에 관한 연구 (Study on the Antibiotic Effect of Casual Shoe Usage Leather)

  • 신수범;민병욱;허종수;김원주
    • Applied Biological Chemistry
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    • 제44권4호
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    • pp.257-261
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    • 2001
  • 조직학적으로 피혁을 구성하고 있는 콜라겐 단백질의 성분은 미생물의 생육 조건 여부에 따라 수분을 비롯한 여러 가지 양질의 영양원을 가지고 있다. 본 연구에서는 피혁 제조 공정 중 탄닝 공정에서 항균제의 종류별 활용 실험을 통해서 피혁의 층별 항균성 효과, 세탁에 대한 항균 지속성 연구, 가죽의 유연성(softness)을 부여하기 위하여 사용하는 가지제(fatliquor)의 종류가 항균성에 미치는 영향 등을 검토하였다. 연구 결과 피혁의 층별 실험에서는 동일한 항균제를 처리시 grain layer>middle layer>flesh layer 순으로 항균성이 우수함을 알 수 있었다. 세탁에 대한 항균 지속성 실험에서는 세탁 횟수에 비례해서 향균력이 저하되는 일반적인 경향을 나타내었는데, 특별히 OITZ 계통의 항균제는 TCMTB 및 CMK 계통의 항균제보다 그 감소폭이 적음을 알 수 있었다. 가지제가 항균성에 미치는 영향을 검토한 결과 sulfated fatliquor(황산화 가지제)가 phosphated fatliquor(인산화 가지제)에 비해 상대적으로 더 큰 항균력을 지님을 알 수 있었다.

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Insights into the in vitro germicidal activities of Acalypha indica

  • Rahman, Md. Shahedur;Hossain, Riad;Saikot, Forhad Karim;Rahman, Shaikh Mizanur;Saha, Subbroto Kumar;Hong, Jongki;Kim, Ki-Hyun
    • 분석과학
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    • 제30권1호
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    • pp.26-31
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    • 2017
  • Background and purpose: This study was carried out to learn more about the potential prophylactic or antibacterial activity of the plant Acalypha indica against selective pathogenic bacteria. Experimental: The test organisms were Sarcina lutea IFO 3232, Bacillus subtilis IFO 3026, Pseudomonas denitrificans, Escherichia coli IFO 3007, Klebsiella pneumoniae ATTC 10031, Xanthomonas campestris IAM 1671, and Proteus vulgaris. Leaf, stem, and bud powder of Acalypha indica were dissolved in various solvents, and the extracts were tested for antimicrobial activity through the disc diffusion method. GC-MS profiling was performed to characterize active chemical compounds in the essential oil of Acalypha indica. Results: The ethanol extract showed the highest activity against all bacteria, while the petroleum ether extract yielded the highest zone of inhibition against Proteus vulgaris ($11.83{\pm}1.75mm$). The minimum inhibitory concentration (MIC) of the ethyl acetate extract against Bacillus subtilis was 16 µg/mL. Phytochemical screening by GC-MS revealed a total of 12 bioactive compounds. Conclusion: Extracts of Acalypha indica may be useful in formulating and synthesizing new antibacterial drugs.