scholarly journals Spectrum of Imipenem and Meropenem Susceptibilities amongst Gram Negative Rods

2021 ◽  
Vol 15 (7) ◽  
pp. 1807-1809
Author(s):  
Sadia Ikram ◽  
Anila Errum ◽  
Asma Inam ◽  
Farrukh Sarfaraz ◽  
Sadia Majeed ◽  
...  
Keyword(s):  
Susceptibility Testing ◽  
Carbapenem Resistance ◽  
Salmonella Typhi ◽  
Diffusion Method ◽  
Gram Negative Bacteria ◽  
Klebsiella Species ◽  
Gram Negative ◽  
E Coli ◽  
Microbiological Techniques ◽  
Resistance Spectrum

Aim: To compare the resistance amongst Gram negative bacteria against imipenem and meropenem. Study Design: Prospective, non-randomized, descriptive study. Place and Duration of Study: Department of Microbiology, Mughal Laboratories, Lahore from 1stJuly 2019 to 31stDecember 2019. Methodology: One hundred culture samples received, bacteria isolated and their susceptibilities to imipenem and meropenem were compared. Organisms were recognized by the microbiological techniques according to the current standards and susceptibility testing was done according to the guidelines of Clinical and Laboratory Standards Institute (CLSI) 2020by using Kirby Bauer Disc diffusion method. Results: Salmonella typhi, Citrobacter species and Proteus species were 100% sensitive to imipenem. The rest of bacterial isolates had sensitivities to E. coli 88%, Acinetobacter 80%, Klebsiella species 67% and Peudomonas species 64%. The meropenem is highly resistant in all the bacteria as compared to imipenem. Conclusion: Increasing the trend of carbapenem resistance amongst Gram negative bacteria excluding Salmonella typhi was recorded. Key words: Gram negative rods, Resistance, Spectrum

scholarly journals 128. Adequacy of Commonly Prescribed Antimicrobials for Empiric Coverage of Gram-Negative Bacterial Pathogens Recovered from the Bloodstream of Patients Attending Emergency Rooms in Canada: Analysis of Data from the CANWARD Study, 2007 to 2018

2019 ◽  
Vol 6 (Supplement_2) ◽  
pp. S93-S93
Author(s):  
Andrew Walkty ◽  
Heather Adam ◽  
Melanie Baxter ◽  
Amina Henni ◽  
Philippe Lagace-Wiens ◽  
...  
Keyword(s):  
Susceptibility Testing ◽  
Diffusion Method ◽  
Gram Negative Bacteria ◽  
Bacterial Isolates ◽  
Emergency Rooms ◽  
Disk Diffusion Method ◽  
Gram Negative ◽  
E Coli ◽  
Gram Negative Bacteremia ◽  
Average Proportion

Abstract Background Inadequate empiric antimicrobial therapy for Gram-negative bacteremia is associated with adverse clinical outcomes. The purpose of this study was to evaluate the proportion of Gram-negative bacterial isolates recovered from the bloodstream of patients attending Canadian emergency rooms (ERs) that remain susceptible to commonly prescribed antimicrobials. Methods Annually from 2007 to 2018, sentinel hospitals across Canada collected bloodstream isolates from patients attending ERs as part of the CANWARD study. Susceptibility testing was performed using broth microdilution as described by CLSI (data analysis limited to Gram-negative bacteria in the top 10 pathogens), with current CLSI breakpoints applied. Extended-spectrum β-lactamase (ESBL)-producing isolates were confirmed using the CLSI disk diffusion method. Results Gram-negative bacteria among the top 10 bloodstream pathogens for patients seen at ERs across Canada were: Escherichia coli (n = 2,414), Klebsiella pneumoniae (n = 573), Pseudomonas aeruginosa (n = 211), Proteus mirabilis (n = 119), and Enterobacter cloacae (n = 114). Aggregate susceptibility of these isolates to common antimicrobials was as follows (% susceptible [S]): meropenem 99.4% S, piperacillin–tazobactam 98.5% S, gentamicin 93.3% S, ceftriaxone 88.1% S, ciprofloxacin 81.4% S, TMP-SMX 73.5% S. The most active antimicrobials evaluated vs. E. coli were meropenem (100% S), piperacillin–tazobactam (98.8% S), and ceftriaxone (93.3% S). Ceftriaxone susceptibility among E. coli isolates declined from 95.4% in 2007 to 89.8% in 2018. The average proportion of E. coli isolates that harbored an ESBL enzyme increased from 3.4% in the first three study years to 8.4% in the last three study years. The most active antimicrobials evaluated vs. K. pneumoniae isolates were meropenem (99.7% S), piperacillin–tazobactam (98.8% S), gentamicin (97.7% S), and ceftriaxone (96.9% S). Conclusion The most consistently active antimicrobials for empiric treatment of patients at Canadian ERs with Gram-negative bacteremia are meropenem and piperacillin–tazobactam. Ceftriaxone susceptibility among E. coli has declined over the last 12 years, mostly related to an increase in ESBL-producing isolates. Disclosures All authors: No reported disclosures.

scholarly journals Frequency of ESBL in Surgical Site Infection at a Tertiary Care Hospital

2014 ◽  
Vol 1 (2) ◽  
pp. 25-29 ◽  
Author(s):  
M Saiful Islam ◽  
M Abdullah Yusuf ◽  
M Badrul Islam ◽  
Waseka Akhter Jahan
Keyword(s):  
Surgical Site Infection ◽  
Diffusion Method ◽  
Gram Negative Bacteria ◽  
Care Hospital ◽  
Site Infection ◽  
Klebsiella Species ◽  
Gram Negative ◽  
E Coli ◽  
Pseudomonas Species ◽  
Esbl Producers

Background: Infection caused by ESBL in the surgical site infection is very alarming. Objective: The purpose of the present study was to see the status of ESBL bacteria isolated from surgical site infection with their antimicrobial sensitivity pattern.Methodology: This cross sectional study was conducted in the Department of Microbiology at Dhaka Medical College, Dhaka from January, 2005 to December, 2005 for a period of one (1) year. All the patients presented with surgical site infections at any age with both sexes were included a study population. Detection of extended spectrum beta lactamase producing Gram negative bacteria was done by using disc diffusion method and was confirmed by E- test ESBL method. Sensitivity pattern of ESBL producers were observed against quinolone and fluoroquinolones. ESBLs are the enzymes capable of hydrolyzing all penicillin, monobactam and cephalosporins except cephamycin, but inactive against imipenem.Result: A total number of 92 surgical wound samples were collected of which 68(73.9%) samples were culture positive. Interestingly, most of the E. coli was ESBL positive (55.0%). Klebsiella species was 33.1% ESBL positive. ESBL positivity of Proteus and Pseudomonas species were low (11.1%). Among the isolated Pseudomonas species, 1(6.67%) of the 15 strains isolated from wound swab was ESBL producers. ESBL positivity was significantly found in surgically wound samples (p=0.0001). Among the ESBL producers, all the E. coli, Klebsiella species, Proteus species and Pseudomonas species were resistant to amoxicillin, cephradine, ceftriaxone, aztreonam, ceftazidime and cefotaxime. All the Gram negative bacteria were sensitive to imipenam. Conclusion: A considerable numbers of ESBL producing bacteria were detected from surgical wound.DOI: http://dx.doi.org/10.3329/jcamr.v1i2.20514 Journal of Current and Advance Medical Research Vol.1(2) 2014: 25-29

scholarly journals Molecular characterization and replicon typing of plasmids encoding carbapenemases in Gram-negative bacteria

2019 ◽  
Author(s):  
Prasanth Manohar ◽  
Manali Kale ◽  
Bruno S. Lopes ◽  
Nachimuthu Ramesh
Keyword(s):  
Tamil Nadu ◽  
Public Health Problem ◽  
Carbapenem Resistance ◽  
Dilution Method ◽  
Gram Negative Bacteria ◽  
Klebsiella Species ◽  
Gram Negative ◽  
E Coli ◽  
Plasmid Incompatibility ◽  
Diagnostic Center

Abstract Background Carbapenem resistance in Gram-negative bacteria is an ongoing public-health problem of global dimensions leaving very few treatment options for severely infected patients. This study focuses on the dissemination of plasmid-borne carbapenemase genes in Gram-negative bacteria in Tamil Nadu, India. A total of 151 non-repetitive isolates belonging to 11 genera were collected from a diagnostic center in Tamil Nadu. Minimal inhibitory concentration of imipenem and meropenem were determined using micro-broth dilution method. E. coli pathotyping, Klebsiella serotyping, screening for beta-lactamases and plasmid incompatibility grouping was performed.Results E. coli (n=57) isolates were classified as, Enteropathogenic (n=12), Enteroaggregative (n=9), Enterohemorrhagic (n=8), Enterotoxigenic (n=3), Enteroinvasive (n=1) and unclassified E. coli (n=24). Of the 45 Klebsiella species, 14 were K1 whereas 11 were K2 serotype and in 20 Klebsiella serotype could not be determined. Other isolates (n=49) consisted of P. aeruginosa , S. typhi , E. cloacae , A. baumannii , S. marcescens , A. xylosoxidans , P. mirabilis and E. meningoseptica . Of the total number of isolates, 71% (n=107) and 68% (n=103) were found to be resistant to meropenem and imipenem respectively. The most prevalent beta-lactamase gene was bla NDM-1 (21%, 12/57) followed by bla OXA-181 (16%, 9/57) both detected in E. coli . Other carbapenemase genes detected were bla GES-9 (n=8), bla OXA-23 (n=7) and bla IMP-1 (n=3). Interestingly bla GES-1 (n=11), bla OXA-51 (n=9) were also detected. The unusual presence of bla OXA-23 was seen in E. coli (n=4), and bla OXA-23 and bla OXA-51 (IncA/C) in K. pneumoniae (n=3). Plasmid incompatibility (inc/rep) typing results showed that the plasmids carrying resistance genes (n=11) belonged to IncX, IncA/C, IncFIA-FIB and IncFIIA groups. Six E. coli isolates and one K. pneumoniae were able to transfer plasmid-borne carbapenemase ( bla NDM-1 , bla OXA-181 , bla GES-1 , bla GES-9 ) via conjugation.Conclusions This study highlights the prevalence of carbapenem resistance and the acquisition of plasmid-borne carbapenemase genes in unusual Gram-negative bacteria highlighting the role of evolution by generating microbial diversity.

scholarly journals Utilization of Vector Autoregressive and Linear Transfer Models to Follow Up the Antibiotic Resistance Spiral in Gram-negative Bacteria From Cephalosporin Consumption to Colistin Resistance

2018 ◽  
Vol 69 (8) ◽  
pp. 1410-1421 ◽  
Author(s):  
Hajnalka Tóth ◽  
Adina Fésűs ◽  
Orsolya Kungler-Gorácz ◽  
Bence Balázs ◽  
László Majoros ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Carbapenem Resistance ◽  
Gram Negative Bacteria ◽  
Vicious Cycle ◽  
Var Models ◽  
Gram Negative ◽  
Vector Autoregressive ◽  
E Coli ◽  
Cephalosporin Resistance ◽  
Klebsiella Spp

Abstract Background Increasing antibiotic resistance may reciprocally affect consumption and lead to use of broader-spectrum alternatives; a vicious cycle that may gradually limit therapeutic options. Our aim in this study was to demonstrate this vicious cycle in gram-negative bacteria and show the utility of vector autoregressive (VAR) models for time-series analysis in explanatory and dependent roles simultaneously. Methods Monthly drug consumption data in defined daily doses per 100 bed-days and incidence densities of gram-negative bacteria (Escherichia coli, Klebsiella spp., Pseudomonas aeruginosa, and Acinetobacter baumannii) resistant to cephalosporins or to carbapenems were analyzed using VAR models. These were compared to linear transfer models used earlier. Results In case of all gram-negative bacteria, cephalosporin consumption led to increasing cephalosporin resistance, which provoked carbapenem use and consequent carbapenem resistance and finally increased colistin consumption, exemplifying the vicious cycle. Different species were involved in different ways. For example, cephalosporin-resistant Klebsiella spp. provoked carbapenem use less than E. coli, and the association between carbapenem resistance of P. aeruginosa and colistin use was weaker than that of A. baumannii. Colistin use led to decreased carbapenem use and decreased carbapenem resistance of P. aeruginosa but not of A. baumannii. Conclusions VAR models allow analysis of consumption and resistance series in a bidirectional manner. The reconstructed resistance spiral involved cephalosporin use augmenting cephalosporin resistance primarily in E. coli. This led to increased carbapenem use, provoking spread of carbapenem-resistant A. baumannii and consequent colistin use. Emergence of panresistance is fueled by such antibiotic-resistance spirals.

scholarly journals Occurrence of Escherichia coli in captive psittaciformes: antimicrobial susceptibility and virulence genes

2020 ◽  
Vol 21 ◽  
Author(s):  
Karine Louise Calaça ◽  
Renato Clini Cervi ◽  
Silvânia Andrade Reis ◽  
Iolanda Aparecida Nunes ◽  
Valéria de Sá Jayme ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Susceptibility ◽  
Virulence Genes ◽  
Susceptibility Testing ◽  
Metropolitan Region ◽  
Serum Resistance ◽  
Gram Negative Bacteria ◽  
Gram Negative ◽  
E Coli ◽  
Hygienic Conditions

Abstract Captive Psittaciformes may harbor Gram-negative bacteria in their digestive tract, mainly due to poor hygienic conditions and confinement. The present study was carried out with the objective of isolating and identifying Escherichia coli in samples collected from Psittaciformes cages in 50 commercial establishments in the metropolitan region of Goiania, with subsequent antimicrobial susceptibility testing and detection of virulence genes. A total of 141 samples of excreta and swab samples from feeders and water bowls were collected, totaling 423 samples. Escherichia coli was isolated from 9.7% (41/423) samples: 12% (17/141) in excreta, 8.5% (12/141) in feed, and 8.5% (12 /141) in waterers. To determine the susceptibility profile of E. coli isolates, resistance to ciprofloxacin 4.9% (2/41), gentamicin 17.0% (7/41), doxycycline 34.1% (14/41), florfenicol 34.1% (14/41), trimethoprim 39.0% (16/41), tetracycline 41.5% (17/41), enrofloxacin 43.9% (18/41), amoxicillin 48.8% (20/41), neomycin 61.0% (25/41), and sulfonamide 90.2% (37/41) was determined. In 20 isolates, resistance was determined at 4 or more antimicrobials, seven of excreta (7/17), five of feed (5/12), and eight of waterers (8/12). One of the isolates from the waterers showed resistance to all antimicrobials. The iss gene was detected in three isolates, the tsh gene in three, the papC gene in two, traT and eae genes were not detected. In this study, it can be concluded that Psittaciformes commercialized as pet are carry E. coli isolates resistant to most commonly used antimicrobials, mainly sulfonamides and neomycin, besides having virulence and serum resistance genes, which highlights the possibility of the to cause disease in humans.

scholarly journals Dissemination of Carbapenem-resistance and Plasmids-encoding Carbapenemases in Gram-negative Bacteria Isolated from India

2020 ◽  
Author(s):  
Prasanth Manohar ◽  
Sebastian Leptihn ◽  
Bruno S. Lopes ◽  
Nachimuthu Ramesh
Keyword(s):  
Tamil Nadu ◽  
Treatment Options ◽  
Public Health Problem ◽  
Carbapenem Resistance ◽  
Gram Negative Bacteria ◽  
Gram Negative ◽  
E Coli ◽  
Diagnostic Center ◽  
Lactamase Gene

AbstractCarbapenem resistance in Gram-negative bacteria is an ongoing public-health problem of global dimensions leaving very few treatment options for severely infected patients. This study focuses on the dissemination of plasmid-borne carbapenemase genes in Gram-negative bacteria in Tamil Nadu, India. A total of 151 non-repetitive isolates belonging to 11 genera were collected from a diagnostic center in Tamil Nadu. E. coli (n=57) isolates were classified as, Enteropathogenic (n=12), Enteroaggregative (n=9), Enterohemorrhagic (n=8), Enterotoxigenic (n=3), Enteroinvasive (n=1) and unclassified E. coli (n=24). Of the 45 Klebsiella species, 14 were K1 whereas 11 were K2 serotype and in 20 Klebsiella serotype could not be determined. Other isolates (n=49) consisted of P. aeruginosa, S. typhi, E. cloacae, A. baumannii, S. marcescens, A. xylosoxidans, P. mirabilis and E. meningoseptica. Of the 151 isolates, 71% (n=107) and 68% (n=103) were found to be resistant to meropenem and imipenem respectively. The most prevalent beta-lactamase gene was blaNDM-1 (21%, 12/57) followed by blaOXA-181 (16%, 9/57), blaGES-9 (n=8), blaOXA-23 (n=7), blaIMP-1 (n=3), blaGES-1 (n=11) and blaOXA-51 (n=9). The unusual presence of blaOXA-23 was seen in E. coli (n=4), and blaOXA-23 and blaOXA-51 (IncA/C) in K. pneumoniae (n=3). Plasmid incompatibility (inc/rep) typing results showed that the plasmids carrying resistance genes (n=11) belonged to IncX, IncA/C, IncFIA-FIB and IncFIIA groups. E. coli and K. pneumoniae were able to transfer plasmid-borne carbapenemase via conjugation. This study highlights the prevalence of carbapenem resistance and the acquisition of plasmid-borne carbapenemase genes in Gram-negative bacteria highlighting the role of plasmid transfer in disseminating resistance.

scholarly journals Synthesis, Characterization and Antimicrobial Activities of Co (III) and Fe (III) Complexes of Imino-N-heterocyclic Carbenes Ligands

2021 ◽  
pp. 59-67
Author(s):  
Samaila Abubakar ◽  
Musa Muktari ◽  
Rejoice Atiko
Keyword(s):  
Escherichia Coli ◽  
Salmonella Typhi ◽  
Antimicrobial Activities ◽  
Heterocyclic Carbenes ◽  
Gram Negative Bacteria ◽  
Disc Diffusion ◽  
Gram Negative ◽  
E Coli ◽  
Gram Positive Bacteria

The synthesis and antimicrobial application of Co (III) and Fe (III) complexes of imine functionalized N-heterocyclic carbene (Imino-NHC) ligands is reported. The ligand precursors 1-(2-[(hydroxyl-benzylidene)-amino]-ethyl)-3-R-3H-imidazol-1-ium bromide where R = pyridyl (1a) and benzyl (1b) have been reported in our previous work. The in-situ generated ligands of 1a and 1b have been successfully coordinated to CoBr2 and [FeI(Cp)(CO)2] leading to the isolation of air-stable N^C^N^O four coordinate Co(III)  complex 2 and a six-coordinate Fe(III) complex 3. The synthesised complexes were both found to be NMR inactive hence were characterize using FTIR and LRMS. The complexes were screened for antimicrobial activities against four gram-negative bacteria Escherichia Coli (E-coli), Shigella, Klebsiella pneumoniae (K. Pneumoniae) and Salmonella typhi (S. typhi) and a gram positive bacteria Staphylocossus aureus (S. aureus). The antimicrobial test was conducted using disc diffusion methods and based on the concentrations of 100, 200, 300, 400 and 500 µg/ mL, significant activities were recorded for both cobalt and the iron complexes.

scholarly journals Performance of the BD Phoenix CPO detect assay for detection and classification of carbapenemase-producing organisms

2020 ◽  
Author(s):  
Laura Berneking ◽  
Anna Both ◽  
Benjamin Berinson ◽  
Armin Hoffmann ◽  
Marc Lütgehetmann ◽  
...  
Keyword(s):  
Susceptibility Testing ◽  
Carbapenem Resistance ◽  
Alternative Methods ◽  
Gram Negative Bacteria ◽  
Accurate Identification ◽  
Gram Negative ◽  
Carbapenem Resistant ◽  
Gradient Diffusion ◽  
Assay Performance

AbstractIncreasing worldwide, prevalence of carbapenem-resistant gram-negative bacteria demands urgent a need for rapid detection and accurate identification of carbapenemases. The BD Phoenix CPO detect (PCD) assay possesses an in-built capacity for parallel susceptibility testing and detection of carbapenemases. Here, the ability of the assay to detect and classify carbapenemase production was tested in a collection of carbapenem-resistant Enterobacterales and non-fermentative gram-negative rods. The ability of the PCD assay to detect and classify carbapenemases was investigated in a collection of 194 clinical, carbapenem-resistant isolates (Enterobacterales [n = 65]; non-fermentative gram-negative rods [n = 129]). AST results were compared to MICS determined by gradient diffusion to determine accuracy of the PCD assay. The accuracy of the PCD assay to detect carbapenemases was compared to the results of molecular isolate characterization using a LDT multiplex carbapenemase PCR assay. All 194 isolates classified as carbapenem-resistant by reference susceptibility testing were also classified correctly as CRO by the PCD assay. Performance analysis of the PCD assay to detect carbapenemase production revealed an overall sensitivity of 98.29% and specificity of 17.95% for the detection of carbapenemase production. For the classification of carbapenemases classes A, B, and D, the PCD correctly classified 79.17% Enterobacterales and 67.16% non-fermentative gram-negative rods. The PCD assay is a reliable tool for the detection of carbapenem resistance and allows for parallel analysis of carbapenemase production. However, while sensitivity is high, low specificity in carbapenemase detection and erroneous classification demands mandatory confirmation by alternative methods, especially in non-fermentative gram-negative bacteria.

Exogenous Production of N-acetylmuramyl-L Alanine Amidase (LysM2) from Siphoviridae Phage Affecting Anti-Gram-Negative Bacteria: Evaluation of Its Structure and Function

2022 ◽  
Author(s):  
Morteza Miri ◽  
Sepideh Yazdianpour ◽  
Shamsozoha Abolmaali ◽  
Shakiba Darvish Alipour Astaneh
Keyword(s):  
In Silico ◽  
Alpha Helix ◽  
Salmonella Typhi ◽  
Structure And Function ◽  
Gram Negative Bacteria ◽  
Gene Encoding ◽  
Gram Negative ◽  
E Coli ◽  
Antigenic Properties ◽  
And Function

Background: To obtain endolysin with impact(s) on gram-negative bacteria as well as gram-positive bacteria, N-acetylmuramyl L-alanine-amidase (MurNAc-LAA) from a Bacillus subtilis-hosted Siphoviridae phage (SPP1 phage, Subtilis Phage Pavia 1) was exogenously expressed in Escherichia coli (E. coli).  Methods: The sequences of MurNAc-LAA genes encoding peptidoglycan hydrolases were obtained from the Virus-Host database. The sequence of MurNAc-LAA was optimized by GenScript software to generate MurNAc-LAA-MMI (LysM2) for optimal expression in E. coli. Furthermore, the structure and function of LysM2 was evaluated in silico. The optimized gene was synthesized, subcloned in the pET28a, and expressed in E. coli BL21(DE3). The antibacterial effects of the protein on the peptidoglycan substrates were studied. Results: LysM2, on 816 bp gene encoding a 33 kDa protein was confirmed as specific SPP1 phage enzyme. The enzyme is composed of 271 amino acids, with a half-life of 10 hr in E. coli. In silico analyses showed 34.2% alpha-helix in the secondary structure, hydrophobic N-terminal, and lysine-rich C-terminal, and no antigenic properties in LysM2 protein. This optimized endolysin revealed impacts against Proteus (sp) by turbidity, and an antibacterial activity against Klebsiella pneumoniae, Salmonella typhi-murium, and Proteus vulgaris in agar diffusion assays. Conclusion: Taken together, our results confirmed that LysM2 is an inhibiting agent for gram-negative bacteria.

Comparison of Media for Determining Temperature Abuse of Fresh Broiler Carcasses Using Impedance Microbiology

1995 ◽  
Vol 58 (10) ◽  
pp. 1124-1128 ◽  
Author(s):  
SCOTT M. RUSSELL ◽  
DANIEL L. FLETCHER ◽  
NELSON A. COX
Keyword(s):  
Broiler Chicken ◽  
Brain Heart Infusion ◽  
Plate Count ◽  
Gram Negative Bacteria ◽  
Gram Negative ◽  
E Coli ◽  
Plate Count Agar ◽  
Processing Plants ◽  
Microbiological Techniques ◽  
The Ideal

Experiments were conducted to determine the ideal medium for detection of temperature abuse of fresh broiler chicken using impedance microbiological techniques. In three separate trials, 15 ready-to-cook broiler chicken carcasses were obtained from the chiller exit of three separate processing plants. Five carcasses were sampled immediately (day 0), 5 carcasses were sampled after temperature abusing at 25°C for 12 h and holding at 3°C for 6 days (temperature abused), and the remaining 5 carcasses were sampled after holding at 3°C for 7 days (day 7 controls). Whole-carcass rinses were diluted by placing 1 ml from each carcass into 9 ml of each of the following media: (1) brain heart infusion broth (BHI), (2) EC broth with 3% added dextrose (ECD), (3) CM medium with 2% added dextrose (CMD), (4) EC broth (EC), and (5) CM medium (CM). The diluted samples were assayed in duplicate at 43°C using impedance microbiological techniques. Once a detection time (DT) was recorded, one ml of the sample was immediately recovered from the module well, diluted to 10−6, 10−7, and 10−8, and spread plated onto plate count agar. Two colonies from each carcass on plates with the highest dilution were randomly selected and identified. Since both gram-positive and gram-negative genera of bacteria were isolated from BHI-cultured carcass rinses and were responsible for changing the impedance of the medium, DTs were variable. EC and ECD media were not suitable for conducting temperature-abuse determinations. Using CMD medium to select for the growth of gram-negative bacteria, specifically E. coli, temperature-abuse determinations were more accurate than using a general medium, such as BHI. CMD appears to be the most effective medium tested to conduct temperature abuse determinations using impedance microbiological techniques.

Sign in / Sign up

Export Citation Format

Share Document