Characterization of Klebsiella isolates by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and determination of antimicrobial resistance with VITEK 2 advanced expert system (AES)

WOS: 000365510300024PubMed ID: 26775392Background/aim: The purpose of the study was to evaluate the performance of the VITEK mass spectrometry (MS) (bioMerieux, France) system for the identification of Klebsiella spp. isolated from different sources. Moreover, while assessing the ability of the VITEK 2 automated expert system (AES) to recognize antimicrobial resistance patterns, the researchers have extended the study to compare VITEK 2 with the routine antimicrobial susceptibility testing method. Materials and methods: This study tested 51 Klebsiella spp. isolates that were isolated from environmental examples and clinical examples. Results of conventional methods and the matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) MS were compared. Then, any differing results were compared against a reference 16S rRNA gene sequence, and when indicated, a recA sequencing analysis was done. Results: VITEK MS correctly identified 100% of the Klebsiella spp. isolates. There were two K. oxytoca isolates incorrectly identified to the species level with conventional methods according to the 16S rRNA gene sequencing analysis. In addition, a VITEK 2 AST-N261 card was used for the detection of extended spectrum beta-lactamases (ESBL). Using the VITEK 2 AES, ESBL positivity was found at the rate of 16.3% whereas this rate was 4.08% using the disk diffusion method. Conclusion: MALDI-TOF MS is a rapid and accurate method for the identification of Klebsiella spp. Moreover, the bioMerieux AES provides a useful laboratory tool for the interpretation of susceptibility results

Spectral, Thermal and Antimicrobial Properties of Novel Mixed Ligand-Metal Complexes Derived from Saccharinate Complexes and Azo Dye Ligand

Background and Objective: Saccharin and saccharinate (sac) complexes and its anion have critical importance with biological, biochemical and pharmacological properties. The main objective of this study was to synthesize the novel mixed ligand complexes from the complexes [M(Sac)2(H2O)4]·2H2O [M: Mn(II), Co(II), Ni(II), Cu(II) and Cd(II)] with a second neutral ligand [L:(mmppa): 5-Methyl-4-(4-methylphenylazo)-2H-pyrazole-3-ylamine]. Methodology: The structures of the complexes were characterized by elemental analysis, magnetic susceptibility, FT-IR, mass and electronic spectral studies and thermal analysis. Antimicrobial (antibacterial and anticandidal) activities of the complexes were tested against Enterococcus faecalis ATCC 51299, Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 35218, Pseudomonas aeruginosa ATCC 27853, Klebsiella pneumoniae ATCC 700603 and Candida albicans ATCC 64548. Results: According to the experimental results, it was determined that in Mn(II), Co(II) and Cd(II) complexes, two coordinated H2O molecules are replaced with two neutral ligands, on the other hand, in Ni(II) and Cu(II) complexes, all coordinated H2O molecules are replaced with four neutral ligands. It was established that the second neutral ligand was coordinated to the metal ions via nitrogen atom of-NH2 group in pyrazole ring. In antimicrobial activity, study was determined to occur significant inhibition zones (20-24 mm) against Candida albicans ATCC 64548 strain. Conclusion: As a result, mononuclear and monomeric structure in octahedral geometry including both saccharin and azo dye ligands were synthesized and their characterizations were accomplished. The result of this study shows that novel mixed ligand-saccharinate complexes can be utilized for the development of anticandidal agents. © 2018 Ragip Adiguzel et al.MUNIBAP-MFTUB013-05The authors are grateful to Research Foundation of Munzur University (Grant No: MUNIBAP-MFTUB013-05) for supporting this study

The Research of Clonal Relationship Among Aeromonas Strains Isolated from Human, Animal and Drinking Water by PFGE

WOS: 000321748400015Aeromonads infect human through potable water and causes various infections. Their existence in animal are being assessed as potential risk for human health. The aim of this study was to investigate clonal relationship among 52 Aeromonas strains isolated from human with diarrhea (14 strains), healthy food workers (2 strains), animals (24 strains) and drinking water (12 strains) by pulsed-field gel electrophoresis (PFGE). Clonal relation was determined between one diarrheic human isolate and one cattle isolate. No clonal relation was determined between drinking water and human isolates. Two fish isolates, A. caviae and A. sobria, were not distinguished PFGE patterns. Consequently no predominant clone was determined while clonal related strains were determined. Particularly, it is necessary to elicit the epidemiological importance of animals in respect of human Aeromonas infections and extensive studies are required for identification of environmental isolates

Synthesis, characterization of poly-2-(2-hydroxybenzylideneamino)-6-phenyl-4,5,6, 7-tetrahydrobenzo[b]thiophene-3-carbonitrile: Investigation of antibacterial activity and optical properties

WOS: 000305473100022The oxidative polycondensation reaction conditions of 2-(2-hydroxybenzylideneamino)-6-phenyl-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carbonitrile were examined. The magnitude of the reflectance of the polymer decreases sharply with increasing of wavelength up to 524 nm, then reflectance of the polymer increases slowly with increasing of wavelength. The refractive index values of the polymer vary from 1.474 to 2.350. The Ep and Ed values of the polymer were found to be 4.56 and 7.068 eV, respectively. Absorption coefficient K of the polymer is of the order 817.0621434.77 m-1. Angle values of incidence and refraction of the polymer vary from 57.36 to 66.95 degrees and from 23.05 to 32.65 degrees, respectively. The film-phase thickness of the polymer increases with increasing photon energy. The thickness, d, of the polymer was of the order 439.34184.7 angstrom for 190 and 1100 nm, respectively. The real part of dielectric constant of the polymer decreases slowly with increasing of frequency up to about 600 THz, then the real part of dielectric constant of the polymer increases sharply with increasing of frequency. The real and imaginary parts of dielectric constant of the polymer vary from 2.17 to 5.52 and from 5.81 x 10(-5) to 3.58 x 10(-4), respectively. Finally, polymer was tested for antibacterial activities against some bacteria. POLYM. ENG. SCI., 2012. (C) 2012 Society of Plastics Engineer

Genotyping of Enterococcus casseliflavus strains isolated from various water samples

European Biotechnology Congress -- SEP 28-OCT 01, 2011 -- Istanbul, TURKEYWOS: 000295310800204…European Biotechnol Themat Network Asso

Prevalence and antibiotic sensitivity of motile Aeromonas in dogs

The present study was carried out to assess the prevalence of motile Aeromonas sp. in the faeces of healthy dogs and to evaluate its susceptibility to some anti-microbial agents. Rectal swabs from 55 domestic dogs were examined for Aeromonas species using alkaline peptone water (pH 8.4) as the enrichment medium and Aeromonas Selective Agar containing 5 mg/l ampicillin as the plating medium. Identification and antibiotic resistance of motile Aeromonas strains was performed using Gram Negative Breakpoint ID panel. After examining these samples, aeromonads were isolated from three (5.45%) dogs. Of those, one was A. sobria, and two were A. caviae. While all isolated strains were sensitive to amikacin, cefoperazone, cefotaxime, cefotetan, ceftazidime, ceftriaxone, cefuroxime, ciprofloxacin, gentamicin, imipenem, piperacillin, tetracycline, ticarcillin, ticarcillin/clavulanate, tobramycin, and trimethoprim/sulfamethoxazole, they were resistant to ampicillin, and ampicillin/sulbactam. In addition, a strain of A. caviae was also resistant to aztreonam

Study of Structure and Spectral Characteristics of the Zinc(II) and Copper(II) Complexes With 5,5-Dimethyl-2-(2-(3-nitrophenyl) hydrazono)cyclohexane-1,3-dione and Their Effects on Optical Properties and the Developing of the Energy Band Gap and Investigation of Antibacterial Activity

WOS: 000333743200011A new chelating ligand, 5,5-dimethyl-2-(2-(3-nitrophenyl)hydrazono)cyclohexane-1,3-dione (L), and four transition metal complexes were synthesized. The ligand and its complexes were characterized by IR, H-1 and C-13-NMR spectra, elemental analyses, magnetic susceptibility, mass spectra, UV-Vis. and thermogravimetry-differential thermal analysis (TGA-DTA). The metal complexes showed different geometric structures. Antibacterial tests of the ligand and complexes were also done. The Zn(II) complexes showed antibacterial activity against Staphylococcus aureus ATCC-25923 at middle level. The optical properties of the ligand and its complexes were extensively investigated by optical measurements. The average transmittance value of the ligand was the highest value, while the average transmittance value of the [CuL2(NO3)(2)]center dot 6H(2)O complex was the lowest value. The optical band gap of the ligand, [(Zn)(2)L(OH)(4)]center dot 2DMF, [ZnL(NO3)(2)(H2O)(2)]center dot 5H(2)O, [CuL2(OAc)]center dot OAc center dot 3.5H(2)O and [CuL2(NO3)(2)]center dot 6H(2)O complexes were calculated and 3.121 eV, 2.180 eV, 1.551 eV, 2.489 eV and 1.556 eV values were found, respectively. The complexes decreased the optical band gap of the ligand. The optical band gap value of the [ZnL(NO3)(2)(H2O)(2)]center dot 5H(2)O complex is the lowest value. The optical band gap value of the ligand is the highest value. The complexes decrease the angle of incidence of the ligand, while complexes increase the angle of refraction of the ligand. The electric susceptibility of the ligand decreases with its complexes

Antimicrobial susceptibilities of Brucella isolates from various clinical speciemens

Purpose: Brucellosis is a worldwide zoonotic disease and still constitutes a major public health problem. In the study we claimed to identify Brucella species from clinical samples of patients with active brucellosis from Van region of Eastern Anatolia and to determine in vitro antimicrobial susceptibilities of these strains to commonly used anti-Brucella agents and a possible new alternative tigecycline. Materials and Methods: A total of 56 Brucella isolates were enrolled the study and the identification of the isolates were based on conventional methods. In vitro activities of an-timicrobials were evaluated by the E test method. Results: All isolates were identified as B. melitensis. MIC90 values of doxycycline, strepto-mycin, rifampin, trimethoprim-sulfamethoxazole and tigecycline were 0.064 mg/L, 1 mg/L, 2 mg/L, 0.125 mg/L and 0.094 mg/L, respectively. Tigecycline had low MIC50 and MIC90 values against all B. melitensis strains; the highest MIC observed was 0.25 ?g/mL. Conclusion: Our data suggest that tigecycline can be a therapeutic alternative option for the treatment of brucellosis. © Ivyspring International Publisher