A Study on Foodborne Bacterial Cross-Contamination During Fresh Chicken Preparation

Background: Cross-contamination of foodborne pathogens from undercooked poultry meat to ready-to-eat food has been shown to be responsible for a number of foodborne disease outbreaks. Various studies have indicated that bacterial cross-contamination occurs during food preparation where bacteria present on food contact other surfaces and cause illness.Objectives: This study evaluated the ability of bacteria to survive and cross-contaminate other foods during the preparation of fresh chicken. Salmonella spp. cross-contamination from chicken to cucumber and utensils under various food handling scenarios was determined.Methods: Two scenarios were tested: in scenario 1, cutting board and knife used for cutting chicken without washing step were sampled.  In scenario 2, cutting board and knife was washed with tap water separately after cutting chicken, and subsequently used for cutting cucumber.  In scenario 1, chicken, cutting board, knife, and hands were sampled, and in scenario 2, cucumber was tested. Fluorescent in situ hybridization (FISH) method, using published Salmonella specific gene probes was used for Salmonella detection in samples taken from cross-contamination scenarios. A culture-based detection by Hektoen enteric agar was used for the confirmation of Salmonella species.Results: All the samples analyzed were found to be positive for Salmonella spp. with different contamination levels. These results were further confirmed by culture based method. In scenario 1, Salmonella spp. was detected by Sal-1 and Salm-63 oligonucleotide probes in all four samples (chicken, cutting board, knife and hands). A high contamination level was observed in chicken samples in comparison to samples collected from cutting board, knife and hands. In scenario 2, Salmonella spp. was detected by Sal-1 and Salm-63 oligonucleotide probes in the cucumber with very low contamination level. Salmonella Enterica was also detected by Sal-3 and Sapath-3 in both scenarios but the contamination level was not high as compared to Salmonella spp.Conclusion: In conclusion, Salmonella spp. cross-contamination during fresh chicken preparation to read-to-eat-food (cucumber) was confirmed by this study. The experimental data obtained in this study clearly suggest that it is extremely difficult to prevent the spread of Salmonella spp. during the preparation of raw poultry-based meals. Therefore, extreme precautions such as proper cleaning and sanitization of utensils, equipment and surfaces should be carefully followed during the preparation of fresh poultry meat-based food items

A Study on Foodborne Bacterial Cross-contamination During Fresh Chicken Preparation

Arab Journal of Nutrition and Exercise                                                                                                       ISSN:2518-6590          Published on 31 st August, 2017 Abstract Background: Cross-contamination of foodborne pathogens from undercooked poultry meat to ready-to-eat food has been shown to be responsible for a number of foodborne disease outbreaks. Various studies have indicated that bacterial cross-contamination occurs during food preparation where bacteria present on food contact other surfaces and cause illness. Objectives: This study evaluated the ability of bacteria to survive and cross-contaminate other foods during the preparation of fresh chicken. Salmonella spp. cross-contamination from chicken to cucumber and utensils under various food handling scenarios was determined. Methods: Two scenarios were tested: in scenario 1, cutting board and knife used for cutting chicken without washing step were sampled.  In scenario 2, cutting board and knife was washed with tap water separately after cutting chicken, and subsequently used for cutting cucumber. In scenario 1, chicken, cutting board, knife, and hands were sampled, and in scenario 2, cucumber was tested. Fluorescent in situ hybridization (FISH) method, using published Salmonella specific gene probes was used for Salmonella detection in samples taken from cross-contamination scenarios. A culture-based detection by Hektoen enteric agar was used for the confirmation of Salmonella species . Results: All the samples analyzed were found to be positive for Salmonella spp. with different contamination levels. These results were further confirmed by culture based method. In scenario 1, Salmonella spp. was detected by Sal-1 and Salm-63 oligonucleotide probes in all four samples (chicken, cutting board, knife and hands). A high contamination level was observed in chicken samples in comparison to samples collected from cutting board, knife and hands. In scenario 2, Salmonella spp. was detected by Sal-1 and Salm-63 oligonucleotide probes in the cucumber with very low contamination level. Salmonella Enterica was also detected by Sal-3 and Sapath-3 in both scenarios but the contamination level was not high as compared to Salmonella spp. Conclusion: In conclusion, Salmonella spp. cross-contamination during fresh chicken preparation to read-to-eat-food (cucumber) was confirmed by this study. The experimental data obtained in this study clearly suggest that it is extremely difficult to prevent the spread of Salmonella spp. during the preparation of raw poultry-based meals. Therefore, extreme precautions such as proper cleaning and sanitization of utensils, equipment and surfaces should be carefully followed during the preparation of fresh poultry meat-based food items

Quantum Dots: Application for the Detection of Salmonella typhimurium

Quantum dots (QDs) or nanocrystals 5 to 50 nm in size have recently emerged as a novel and promising class of fluorophores for cellular imaging. Unlike conventional organic dyes, QDs can be excited by a wide spectrum of wavelengths to give enhanced photostability, and their emission spectra, which differ according to size and material composition, are narrow, symmetrical, and tunable. This novel detection strategy can significantly improve the efficiency of molecular techniques used in the identification of important microbes related to human diseases. The aim of this study was to apply QDs linked antibodies to detect pathogenic Salmonella typhimurium cells. The signal, photostabilty and efficiency of QDs linked antibodies was compared with the organic fluorophore linked antibody for the detection of Salmonella cells. The use of QDs as fluorophores has shown greater enhancement in photostability and brighter signal than conven-tional organic dyes in detecting S. typhimurium cells. This approach might also be extended for the simultaneous detection of more than one pathogenic microorganism in the clinical, food or environmental samples by using specific antibodies linked with the QDs of different sizes and colors

Next-generation sequencing (NGS) platforms: An exciting era of genome sequence analysis

© Springer Nature Singapore Pte Ltd. 2019. DNA referred to as blueprint of life codes for the diversity and function of all the living organisms. Determining DNA sequences of the living organisms not only gives an overview of their genetic makeup, but also provides information about their function. Nonetheless it was not easy to determine the genome sequencing of all the diversity around us especially with the technologies available before 2010. Therefore, determining the sequence of humans and some other organisms only was prioritized. Pioneering methods for DNA sequencing given discovered by Maxam and Gilbert, and Sanger although were very powerful and popular but were not high throughput and economic. Therefore, it was necessary to develop new economic and high-throughput methods that can sequence the biodiversity consequently providing better insights of their possible function. New methods were developed and commercialized by Roche Life Sciences, Thermo Fisher Scientific, Illumina, and Applied Biosystems. These methods generally referred to as next-generation sequencing methods have revolutionized the DNA sequencing. Many sequencing platforms employing NGS have been developed including pyrosequencing, Ion Torrent technology, Illumina/Solexa platform, and SOLiD (Sequencing by Oligonucleotide Ligation and Detection). Further optimization has led to innovative third and fourth-generation platforms as single molecule real-time (SMRT) sequencing by PacBio, nanopore sequencing, etc. As a consequence there is a sharp increase in the number of genomes being published and other genome-based studies since 2012. This has made it easy even to imagine of sequencing the genomes of individuals. Furthermore, scientists are now looking for third-generation sequencers that may be significantly different from the sequencers that are currently available

Assessment of microbial quality in household water tanks in Dubai, United Arab Emirates

© 2017 Korean Society of Environmental Engineers. Provision of safe, accessible, and good water quality in the community is an important step towards reducing various waterborne illnesses. However, improving the quality of water should include spreading awareness to the public regarding the importance of cleaning their household water tanks. The aim of this study was to investigate the microbial quality of water of household water tanks in Dubai. The water samples from household water tanks were collected from forty houses, and a questionnaire was given to the residents to determine the history of the water tanks. The membrane filtration technique was used to quantify heterotrophic and total coliform bacteria on plate count agar and the violet red bile agar respectively. The overall results of this study have shown that 18 out of total 40 household water tanks contained different types of bacteria concentration level beyond local and widely accepted international standards. The overall results of this study indicated that there is a lack of awareness among residents regarding the importance of maintaining proper sanitation and hygiene of the household water tanks

The Potential Role of Nitric Oxide in Halting Cancer Progression Through Chemoprevention

Nitric oxide (NO) in general plays a beneficial physiological role as a vasorelaxant and the role of NO is decided by its concentration present in physiological environments. NO either facilitates cancer-promoting characters or act as an anti-cancer agent. The dilemma in this regard still remains unanswered. This review summarizes the recent information on NO and its role in carcinogenesis and tumor progression, as well as dietary chemopreventive agents which have NO-modulating properties with safe cytotoxic profile. Understanding the molecular mechanisms and cross-talk modulating NO effect by these chemopreventive agents can allow us to develop better therapeutic strategies for cancer treatment

Determination of heavy metals concentration in traditional herbs commonly consumed in the United Arab Emirates

Copyright © 2015 Rania Dghaim et al. Herbs are extensively consumed in the United Arab Emirates for their flavoring and medicinal properties. This study aimed at determining the concentration of heavy metals in selected traditional herbs consumed in the United Arab Emirates (UAE). A total of 81 samples of seven herbs, parsley (Petroselinumcrispum), basil (Ocimum basilicum), sage (Salvia officinalis), oregano (Origanum vulgare), mint (Mentha spicata), thyme (Thymus vulgaris), and chamomile (Matricaria chamomilla), were purchased from the local market in Dubai and analyzed for their cadmium, lead, copper, iron, and zinc contents. Microwave-assisted digestion was applied for the dissolution of the samples and heavy metals concentration was determined using Atomic Absorption Spectrometry (AAS). Metals were found to be present in varied concentrations in the herb samples.The concentration ranges were found as follows: less than 0.1-1.11mg.kg-1 for cadmium, less than 1.0-23.52mg.kg-1 for lead, 1.44-156.24mg.kg-1 for copper, 12.65-146.67mg.kg-1 for zinc, and 81.25-1101.22mg.kg-1 for iron. The findings of the study suggest that most of the analyzed herbs contained unsafe levels of heavy metals that exceeded theWorld Health Organization (WHO) permissible limits (PL)

Indigenously produced biochar retains fertility in sandy soil through unique microbial diversity sustenance: a step toward the circular economy

IntroductionAgricultural productivity in the arid hot desert climate of UAE is limited by the unavailability of water, high temperature, and salt stresses. Growing enough food under abiotic stresses and decreasing reliance on imports in an era of global warming are a challenge. Biochar with high water and nutrient retention capacity and acid neutralization activity is an attractive soil conditioner. This study investigates the microbial community in the arid soil of Dubai under shade house conditions irrigated with saline water and the shift in the microbial community, following 1 year of amendment with indigenously prepared biochar from date palm waste.MethodsAmplicon sequencing was used to elucidate changes in bacterial, archaeal, and fungal community structures in response to long-term biochar amendment. Samples were collected from quinoa fields receiving standard NPK doses and from fields receiving 20 and 30 tons ha−1 of biochar, in addition to NPK for 1 year. Water holding capacity, pH, electrical conductivity, calcium, magnesium, chloride, potassium, sodium, phosphorus, total carbon, organic matter, and total nitrogen in the soil from biochar-treated and untreated controls were determined.Results and discussionThe results show that soil amendment with biochar helps retain archaeal and bacterial diversity. Analysis of differentially abundant bacterial and fungal genera indicates enrichment of plant growth-promoting microorganisms. Interestingly, many of the abundant genera are known to tolerate salt stress, and some observed genera were of marine origin. Biochar application improved the mineral status and organic matter content of the soil. Various physicochemical properties of soil receiving 30 tons ha−1 of biochar improved significantly over the control soil. This study strongly suggests that biochar helps retain soil fertility through the enrichment of plant growth-promoting microorganisms

(-)-Epigallocatechin-3-gallate reverses the expression of various tumor-suppressor genes by inhibiting DNA methyltransferases and histone deacetylases in human cervical cancer cells

There has been increasing evidence that numerous bioactive dietary agents can hamper the process of carcinogenesis by targeting epigenetic alterations including DNA methylation. This therapeutic approach is considered as a significant goal for cancer therapy due to the reversible nature of epigenetic-mediated gene silencing and warrants further attention. One such dietary agent, green tea catechin, (-)-epigallocatechin-3-gallate (EGCG) has been shown to modulate many cancer-related pathways. Thus, the present study was designed to investigate the role of EGCG as an epigenetic modifier in HeLa cells. DNA methyltransferase (DNMT) and histone deacetylase (HDAC) inhibition assays were conducted, and the transcription levels of DNMT3β and HDAC1 were assessed by enzymatic activity assay and RT-PCR, respectively. Furthermore, we studied the binding interaction of EGCG with DNMT3β and HDAC1 by molecular modeling as well as promoter DNA methylation and expression of retinoic acid receptor-â (RARâ), cadherin 1 (CDH1) and death-associated protein kinase-1 (DAPK1) in EGCG-treated HeLa cells by RT-PCR and MS-PCR. In the present study, time-dependent EGCG-treated HeLa cells were found to have a significant reduction in the enzymatic activity of DNMT and HDAC. However, the expression of DNMT3β was significantly decreased in a time-dependent manner whereas there was no significant change in HDAC1 expression. Molecular modeling data also supported the EGCG-mediated DNMT3β and HDAC1 activity inhibition. Furthermore, time-dependent exposure to EGCG resulted in reactivation of known tumor-suppressor genes (TSGs) in HeLa cells due to marked changes in the methylation of the promoter regions of these genes. Overall, the present study suggests that EGCG may have a significant impact on the development of novel epigenetic-based therapy

Sulforaphane inhibits growth of human breast cancer cells and augments the therapeutic index of the chemotherapeutic drug, gemcitabine

Phytochemicals are among the natural chemopreventive agents with most potential for delaying, blocking or reversing the initiation and promotional events of carcinogenesis. They therefore offer cancer treatment strategies to reduce cancer related death. One such promising chemopreventive agent which has attracted considerable attention is sulforaphane (SFN), which exhibits anti-cancer, anti-diabetic, and anti-microbial properties. The present study was undertaken to assess effect of SFN alone and in combination with a chemotherapeutic agent, gemcitabine, on the proliferative potential of MCF-7 cells by cell viability assay and authenticated the results by nuclear morphological examination. Further we analyzed the modulation of expression of Bcl-2 and COX-2 on treatment of these cells with SFN by RT-PCR. SFN showed cytotoxic effects on MCF-7 cells in a dose- and time-dependent manner via an apoptotic mode of cell death. In addition, a combinational treatment of SFN and gemcitabine on MCF-7 cells resulted in growth inhibition in a synergistic manner with a combination index (CI)\u3c1. Notably, SFN was found to significantly downregulate the expression of Bcl-2, an anti-apoptotic gene, and COX-2, a gene involved in inflammation, in a time-dependent manner. These results indicate that SFN induces apoptosis and anti-inflammatory effects on MCF-7 cells via downregulation of Bcl-2 and COX-2 respectively. The combination of SFN and gemcitabine may potentiate the efficacy of gemcitabine and minimize the toxicity to normal cells. Taken together, SFN may be a potent anti-cancer agent for breast cancer treatment