Application of Short Pre-enrichment, and Double Chemistry Real-Time PCR, Combining Fluorescent Probes and an Intercalating Dye, for Same-Day Detection and Confirmation of Salmonella spp. and Escherichia coli O157 in Ground Beef and Chicken Samples

Molecular methods, particularly those based on real-time PCR (qPCR), have become a popular approach to detect pathogens in food samples. This technique may take advantage of hydrolysis fluorescent probes for increased specificity. Even though suitable, this approach loses the capacity of performing result confirmation by melt curve analysis. In the current study, we developed an alternative approach, combining fluorescent probes along with an intercalating dye (SYBR Green) in order to simultaneously detect, and confirm the result, of two foodborne pathogens (Salmonella spp. and Escherichia coli O157). This new approach named double chemistry qPCR was combined with a short pre-enrichment in order to obtain a multiplex “same-day” detection method for the selected pathogens. The evaluation of the novel method in spiked food samples (ground beef and chicken breast) obtained values of relative sensitivity, specificity, and accuracy higher than 95%, and Cohen’s kappa of 0.92, with a Limit of Detection95 below 5 cfu/25 g, demonstrating its reliability. In addition to this, the method was challenged by inoculating heat-stressed bacteria as well as dead ones. It was observed that it was also possible to detect stressed bacteria with an initial inoculation level below 10 cfu/25 g. Also, it was noticed that high initial concentration of either pathogen (higher than 104 cfu/25 g) was needed in order to generate false positive results due to the presence of dead bacteria...
Source: Frontiers in Microbiology - Category: Microbiology Source Type: research

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The objective of this work was to carry out a bibliographic survey of secondary metabolites isolated from the Velloziaceae family, creating a bank of compounds. After the bank was created, four prediction models for potentially active compounds against pathogenic microorganisms (Candida albicans, Escherichia coli, Pseudomonas aeruginosa and Salmonella sp.) were obtained trying to identify which metabolites would be more active against the strains. Four sets of compounds with known activity for microorganisms were selected for the construction of predictive models from the CHEMBL database. Another bank with 163 unique molec...
Source: Journal of the Brazilian Chemical Society - Category: Chemistry Source Type: research
Authors: Casanovas-Moreno-Torres I, Gutiérrez-Soto B, Modovan TD, Expósito-Ruiz M, Navarro-Marí JM, Gutiérrez-Fernández J Abstract The activity of azithromycin against enteritis-producing agents other than Campylobacter spp. was studied. The susceptibility to azithromycin, through gradient test, of 88 clinical isolates (51 Salmonella spp., 23 Aeromonas spp., 10 Shigella sonnei and 4 Yersinia enterocolitica) for one year was studied prospectively. The results were compared with the activity of ampicillin, trimethoprim-sulfamethoxazole and ciprofloxacin by microdilution. For azithro...
Source: New Microbiologica - Category: Microbiology Tags: New Microbiol Source Type: research
Publication date: Available online 1 October 2020Source: Journal of Environmental Chemical EngineeringAuthor(s): Diego Pino-Sandoval, Minerva Villanueva- Rodríguez, María Elena Cantú-Cárdenas, Aracely Hernández-Ramírez
Source: Journal of Environmental Chemical Engineering - Category: Chemistry Source Type: research
CONCLUSIONS: We conclude that heparin stimulated EcN biofilm formation. Both the sulfation and chain-length of heparin contributed to the enhancement of EcN biofilm formation. This study increases the understanding of how heparin affects biofilm formation, indicating the potential role of heparin in promoting intestinal colonization of probiotics that antagonize pathogen infections. PMID: 33011901 [PubMed - as supplied by publisher]
Source: Biotechnology Letters - Category: Biotechnology Authors: Tags: Biotechnol Lett Source Type: research
Authors: Ryuge A, Saito S, Morioka H, Hachiya A, Kato N, Ishimoto T, Kosugi T, Maruyama S Abstract Nontyphoidal Salmonella is a common cause of bacterial gastroenteritis, occasionally causing bacteremia. We herein report the case of an 80-year-old man who presented with bacteremia and pre-renal acute kidney injury (AKI) secondary to diarrhea caused by nontyphoidal Salmonella. Despite AKI improvement on fluid administration, some serological abnormalities, such as hypokalemia, hypophosphatemia, and hypouricemia, and abnormal urinary findings emerged, including renal glycosuria and aminoaciduria. Fractional excretion...
Source: Internal Medicine - Category: Internal Medicine Tags: Intern Med Source Type: research
The emergence and spread of multidrug-resistant gram-negative bacteria (MDR) has become a major public health concern worldwide. This resistance is caused by enzymes-mediated genes (i.e., extended spectrum bet...
Source: BMC Pediatrics - Category: Pediatrics Authors: Tags: Research article Source Type: research
This study assessed the antimicrobial efficacy of synthesized zinc oxide nanoparticles produced using aqueous extracts of pomegranate leaves and flowers designated ZnO-NPs-PL, ZnO-NPs-PF. In the study, oxides of zinc were successfully employed to fabricate nanoparticles using extracts from leaves and flowers of pomegranate (Punica granatum). The nanoparticles obtained were characterized spectroscopically. X-ray diffractive analysis (XRD) revealed the elemental components and nature of the synthesized particles. The fabricated zinc oxide nanoparticle (ZnO-NPs) showed a crystalline structure. The morphology of the nanopartic...
Source: Molecules - Category: Chemistry Authors: Tags: Article Source Type: research
CONCLUSION: The multi-epitope vaccine is a suitable stimulator for immune system and would be a candidate for experimental research. Recent patents describing numerous inventions related to the clinical facets of vaccine peptide against human infectious disease. PMID: 32990553 [PubMed - as supplied by publisher]
Source: Current Aging Science - Category: Geriatrics Tags: Curr Aging Sci Source Type: research
Multidrug-resistant bacteria are among the most important current threats to public health. Typically, they are associated with nosocomial infections. However, some have become prevalent causes of community-acquired infections, such as Neisseria gonorrhoeae, Shigella, Salmonella, and Streptococcus pneumoniae. The community spread of multidrug-resistant bacteria is also a crucial development. An important global threat on the horizon is represented by production of carbapenemases by community-acquired hypervirulent Klebsiella pneumoniae. Such strains have already been found in Asia, Europe, and North America. Prevention of ...
Source: Infectious Diseases Clinics of North America - Category: Infectious Diseases Authors: Source Type: research
Salmonellosis is a common foodborne disease. We previously reported the protection of Caenorhabditis elegans from Salmonella Typhimurium DT104 infection by Lactobacillus zeae LB1. However, the mechanism is not fully understood. C. elegans exhibits behavior plasticity when presented with diverse pathogenic or commensal bacteria. Whether it can exert approach avoidance to S. Typhimurium through altering its neurological activity remains to be determined. In the current study, both the wild type and mutants defective in serotonin or dopamine production of C. elegans were used to investigate olfactory preference of the nematod...
Source: Frontiers in cellular and infection microbiology - Category: Microbiology Source Type: research
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