• Title/Summary/Keyword: acid sensitivity

Search Result 630, Processing Time 0.03 seconds

Early Detection of Epiphytic Anthracnose Inoculum on Phyllosphere of Diospyros kaki var. domestica

  • Lee, Jung-Han;Han, Ki-Soo;Lee, Sun-Cheol;Shim, Chang-Ki;Bae, Dong-Won;Kim, Dong-Kil;Kim, Hee-Kyu
    • The Plant Pathology Journal
    • /
    • v.20 no.4
    • /
    • pp.247-251
    • /
    • 2004
  • We developed a polyclonal antibody (PAh) based- ELISA system to accurately and rapidly monitor inocula on plant surface before onset of anthracnose. Titer of mouse antisera against conidia of Colletotrichum gloeosporioides was determined by using indirect ELISA. It was high enough to be detectable up to ${\times}$ 12,800 dilutions. Absorbance readings exceeded (1.5even at a 10$^{-5}$ dilution. Sensitivity of PAb was precise enough to detect spore concentration as low as 50 conidia/well by indirect ELISA. PAb1 and PAb2 proved to be very sensitive and highly specific to the target pathogen, C. gloeosporioides, apparently discriminating other unrelated pathogens, or epiphytes. Absorbance values for original isolate exceeded 1.0, but no reaction was detected with other isolates, except three other anthracnose fungi: C. gloeosporioides (pepper strain), Glomerella cingulata (apple strain) and C. lagenarium. Our data suggest that PAb1 and PAb2 bind with the protein epitope that partially contains residues of amino acid, arginine, and Iysine. This kit fulfills the require-ments for detecting inoculums before infection and during onset of anthracnose on sweet persimmon.

Immunosensor for Detection of Escherichia coli O157:H7 Using Imaging Ellipsometry

  • Bae Young-Min;Park Kwang-Won;Oh Byung-Keun;Choi Jeong-Woo
    • Journal of Microbiology and Biotechnology
    • /
    • v.16 no.8
    • /
    • pp.1169-1173
    • /
    • 2006
  • Imaging ellipsometry (IE) for detection of binding of Escherichia coli O157:H7 (E. coli O157:H7) to an immunosensor is reported. A protein G layer, chemically bound to a self-assembled layer of 11-mercaptoundecanoic acid (11-MUA), was adopted for immobilization of monoclonal antibody against E. coli O157:H7 (Mab). The immobilization of antibody was investigated using surface plasmon resonance. To fabricate antibody spots on a gold surface, protein G solution was spotted onto the gold surface modified with an 11-MUA layer, followed by immobilizing Mab on the protein G spot. Ellipsometric images of the protein G spot, the Mab spot, and Mab spots with binding of E. coli O157:H7 in various concentrations were acquired using the IE system. The change of mean optical intensity of the Mab spots in the ellipsometric images indicated that the lowest detection limit was $10^3$CFU/ml for E. coli O157:H7. Thus, IE can be applied to an immunosensor for detection of E. coli O157:H7 as a detection method with the advantages of allowing label-free detection, high sensitivity, and operational simplicity.

A study on simultaneous determination of residual sulfonamides in livestock productions by high performance liquid chromatography (HPLC를 이용한 축산식품중 잔류 설폰아미드제의 동시분석법 연구)

  • 황래홍;김영수;윤은선;김기근;이규학
    • Korean Journal of Veterinary Service
    • /
    • v.18 no.3
    • /
    • pp.13-28
    • /
    • 1995
  • This study was carried out to explore the most sensitive and useful method for simultaneous determination of five sulfa drugs(sulfamethazine, sulfamerazine, sulfamonomethoxine, sulfadimethoxine, sulfaquinoxaline) in livestock productions(pork muscle, bovine muscle, chicken muscle, milk ) by HPLC with UV detector and reverse phase column. The results obtained were as follows:1. For mobile phase acetonitrile-0.01M ammonium acetate (23:77) showed more applicable sensitivity and retention times than acetonitrile-1% acetic acid(23:77). Thus acetonitrile-0.01M ammonium acetate(23:77) selected and applied to the modification test, from which it was found pH 6.75 was the most adequate. 2. Optimal wavelength of UV for SMT(sulfamethazine), SMR(sulfamerazine), SMM(sulfamonomethoxine), SD(sulfadimethoxine), and SQ(sulfaquinoxaline) were 266, 266, 265, 269 and 250nm, respectively, and that for simultaneous application it was 263nm. 3. The average recovery rate by extractant(chloroform, dichloromethane, chlorform+dich-loromethane) in the classic method was not significantly different(p>0.05) but that by chloroform higher than the others. Thus chloroform was found to be adequate as extractant in this classic method. 4. The average recovery rate was 86.5% by the MSPD(matrix solid phase disperse) method, which was significantly higher than that by the classic method(p<0.05). Also the recovery rates by method were significantly different(p<0.05) in accordance with sample and type of drug. The MSPD method was much superior to classic method on clean-up.

  • PDF

Determination of Tocopherol Contents in Refined Edible Oils Using an HPLC Method

  • Hu, Jiang-Ning;Zhu, Xue-Mei;Adhikari, Prakash;Li, Dan;Kim, In-Hwan;Lee, Ki-Teak
    • Preventive Nutrition and Food Science
    • /
    • v.14 no.3
    • /
    • pp.260-264
    • /
    • 2009
  • A high-performance liquid chromatography method was applied to determine the contents of tocopherols in edible oils using a LiChrosorb DIOL HPLC column and hexane fortified with 0.1% acetic acid in an isocratic mode. The validation of the method included tests for linearity, sensitivity, accuracy, precision, and recovery. All calibration curves showed good linear regression ($r^2$>0.9995) within the tested ranges. The established method offered good precision and accuracy with overall intra-day and inter-day variations of 0.94$\sim$4.27 and 1.77$\sim$ 4.88%, respectively. The tocopherol recoveries ranged from 91.44$\sim$108.90%. Subsequently, the method was successfully applied to qualitatively and quantitatively determine the total contents of $\alpha$, $\gamma$, and $\delta$-tocopherols in 12 selected refined edible oils, showing a range of 0.92 to 188.71 mg/100 g.

Comparison of Membrane Currents in Xenopus Oocytes in Response to Injection of Calcium Influx Factor (CIF) and Depletion of Intracellular Calcium Stores

  • Kim, Hak-Yong;Hanley, Michael R.
    • BMB Reports
    • /
    • v.33 no.3
    • /
    • pp.202-207
    • /
    • 2000
  • The depletion of intracellular calcium stores by thapsigargin treatment evoked extracellular calcium-dependent membrane currents in Xenopus laevis oocytes. These currents have been compared to those evoked by microinjection of a calcium influx factor (CIF) purified from Jurkat T lymphocytes. The membrane currents elicited by thapsigargin treatment (peak current, $163{\pm}60$ nA) or CIF injection (peak current, $897{\pm}188$ nA) were both dependent on calcium entry, based on their eradication by the removal of extracellular calcium. The currents were, in both cases, attributed primarily to well-characterized $Ca^{2+}-dependent$ $Cl^-$ currents, based on their similar reversal potentials (-24 mV vs. -28 mV) and their inhibition by niflumic acid (a $Cl^-$ channel blocker). Currents induced by either thapsigargin treatment or CIF injection exhibited an identical pattern of inhibitory sensitivity to a panel of lanthanides, suggesting that thapsigargin treatment or CIF injection evoked $Cl^-$ currents by stimulating calcium influx through pharmacologically identical calcium channels. These results indicate that CIF acts on the same calcium entry pathway activated by the depletion of calcium stores and most lanthanides are novel pharmacological tools for the study of calcium entry in Xenopus oocytes.

  • PDF

Rapid Detection of Fluorescent DNA on Denaturing Polyacrylamide Gel by Using Gel Scanner (겔스캐너를 이용한 변성아크릴아마이드 겔의 형광 DNA 검출)

  • Ku Ja-Hwan;Jeong Ji-Ung;Cho Young-Chan
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.50 no.spc1
    • /
    • pp.228-230
    • /
    • 2005
  • The denature polyacrylamide gel stain silver nitrate is used for routine nucleic acid detection. More sensitive stains, such as Vistra Green, SYBR Green are available to address a broad range of DNA applications requiring lower detection limits in polyacrylamide gel formats. Gel Scanners, laser-scanning instruments, provide sensitive fluorescence detection of DNA gel stains. We established one step fluorescent impregnation enhanced sensitivity with simple, rapid and low cost. We have applied this fluorescent staining procedure for the routine analysis of DNA profiles generated by SSR amplification.

Analytical Techniques for Vancomycin - A Review

  • Avinash P. Sattur;Lee, Je-Hyuk;Song, Ki-Bang;T. Panda;Kim, Chul-Ho;Rhee, Sang-Ki;B. Gokul
    • Biotechnology and Bioprocess Engineering:BBE
    • /
    • v.5 no.3
    • /
    • pp.153-158
    • /
    • 2000
  • Vancomycin belongs to the vancomycin-risocetin family of glycopeptides, and is a subclass of linear sugar containg peptides composed of seven amino acids. Its strochemical configuration forms the basic of a peptidoglycon monomer. The glycosylated hexapeptide chainconsists of chloro-$\beta$-hydroxytyrosines, p-hytidoglycines, N-anthylleucine and aspartic acid forms a rigid molecular frame work and gives the difficulty in the analysis. Voncomycin in the serum samples is usually estimated by liquid chromatography and the bacterial sensitivity was genereally tested by the microbiological assay. The pressent review deals with the qualitative, quantutative, microbioligical and immunological assays and the comparison of the quantitative methods. Clinical implications of vancomycin have also been cited in the review.

  • PDF

Relationship between Colonic Polyp Type and the Neutrophil/Lymphocyte Ratio as a Biomarker

  • Karaman, Hatice;Karaman, Ahmet;Erden, Abdulsamet;Poyrazoglu, Orhan Kursat;Karakukcu, Cigdem;Tasdemir, Arzu
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.14 no.5
    • /
    • pp.3159-3161
    • /
    • 2013
  • Aim: We designed this study to investigate the neutrophil lymphocyte ratio as a biomarker in distinguishing colonic polyps which are neoplastic or non-neoplastic. Materials and Methods: One hundred and twenty-five patients with colonic polyps were enrolled into the study. The following data were obtained from a computerized patient registry database: mean platelet volume (MPV), uric acid (UA), platelet count (PC), alkaline phosphatase (ALP), gamma-glutamyl transpeptidase (GGT) and the neutrophil to lymphocyte ratio (NLR). Exclusion criteria were active infectious disease, hematological disorders, and malignancies. Colonic polyps divided into two groups as neoplastic polyps (tubular adenoma, villous adenoma, tubulovillous adenoma) and non-neoplastic polyps (hyperplastic polyps, inflammatory pseudopolyps etc). The relationship between colonic polyp type and NLR was evaluated with statistical analysis. Results: There were 67 patients (53.6%) with neoplastic and 58 (46.4%) patients with non-neoplastic polyps. Mean NLRs of neoplastic and non-neoplastic groups were respectively $3.32{\pm}2.54$ and $2.98{\pm}3.16$ (P<0.05). Conclusion: Although sensitivity and specificity are not high, NLR may be used as a biomarker of neoplastic condition of colonic polyps.

High sensitivity humidity sensors using polyimide films without fluorinated group (플루오르 그룹을 배제시킨 폴리이미드를 이용한 고감도 습도 센서)

  • Shim, Jae-Hun;Lee, Jun-Young;Kim, Jung-Hyun;Choa, Sung-Hoon;Kim, Yong-Jun
    • Proceedings of the KIEE Conference
    • /
    • 2002.07c
    • /
    • pp.1997-1999
    • /
    • 2002
  • 고분자 주쇄(Main chain)의 소수성을 가지는 플루오르 그룹을 배제시킨 습도 민감성 폴리이미드를 합성 및 이미드화 하였고, 이를 이용한 초고참도 습도 센서를 제작 및 측정하였다. 사용된 폴리이미드는 다이아민계로 Oxydianyline(ODA)와 다이안하이드라이드계로 Pyromellitic dianhydried(PMDA)를 유기용매 Dimethyla cetamide(DMAc) 하에서 폴리이미드 전구체 (Polyamic acid)를 합성하였으며, 진공 및 승온 조건에서 유기용매를 제거하여 이미드화(Imidization) 반응을 진행시켜 제조하였다. 본 습도 센서는 정전용량형 고감도 습도 센서로 디자인되었으며 실리콘 웨이퍼상에서 일반적인 반도체 공정을 이용하여 구현하였다. 본 습도 센서는 센서 크기와 유효면적, 감습층의 두께를 주요 변수로 설정하였으며 이에 따른 습도 민감성 효과를 평가 및 분석하였다. 측정 결과 유효면적 70%, 감습층 두께 $1.1{\mu}m$ 로 제작된 습도 센서는 상대숨도$20%{\sim}90%$ 영역에서 캐패시턴스와 선형적 상관관계를 보여주고 있으며, 습도 민감도는 3.9 pF/%RH 클 얻을 수 있었다.

  • PDF

A Quick Novel Method to Detect the Adulteration of Cow Milk in Goat Milk

  • Lee, Chi-Chei;Chang, His-Shan;Sheen, Hua-Shan
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.17 no.3
    • /
    • pp.420-422
    • /
    • 2004
  • This study was to demonstrate a rapid novel method for detection of adulterated cow milk in goat milk using modified staining protocol after native polyacrylamide gel electrophoresis (PAGE). Samples of cow milk and goat milk containing 0, 0.5, 1.0 and 2.0% (v/v) of cow milk were analyzed. Low levels of cow milk mixed in goat milk were identified by the presence of higher mobility of $\beta$-lactoglobulin A ($\beta$-Lg A) in cow milk. By mini-gel electrophoresis, a distinguishable protein profile was visualized in 25 min using the modified Coomassie blue staining solution, in which methanol (50%) was replaced with ethanol (20%) and the concentrations of Coomassie blue and acetic acid were reduced from 2 to 0.13% and 10 to 5%, respectively. To visualize the milk proteins, gels in the staining solution were water-bathed in boiling water for 5 min and then cooled down immediately for 3-5 min. The sensitivity of this method is relatively high, allowing examination of 1% cow milk in goat milk. The procedure presented here is also very cost-effective due to less reagents needed. This simplified method would be useful and applicable to dairy industry for routine examination of goat milk.