Inactivation of foodborne pathogens on food packaging and in cow milk by exposure to a Nd:YAG laser

2017 ◽  
Vol 95 (7) ◽  
pp. 662-669 ◽  
Author(s):  
N. Yasmin ◽  
S. Hameed ◽  
R. Javed ◽  
S. Ahmed ◽  
M. Imran
Keyword(s):  
Foodborne Pathogens ◽  
Nd:Yag Laser ◽  
Food Packaging ◽  
Pathogenic Bacteria ◽  
Raw Milk ◽  
Cow Milk ◽  
Material Surface ◽  
Laser Exposure ◽  
Agar Surface ◽  
Industrial Level

This study demonstrates the inhibition of selective foodborne pathogenic bacteria by exposure to a 355 and 266 nm Nd:YAG laser. In baseline assay P. aeruginosa showed maximum inhibition followed by Escherichia coli, Staphylococcus aureus, Salmonella typhimurium, and Listeria monocytogenes grown on agar surface. Cell lysis was confirmed by confocal microscopy for all pathogens. In liquid media, P. aeruginosa was irradiated with the third harmonic of a Nd:YAG laser pulse energy of 185 mJ, which was able to reduce the population of 1.65 × 105 by 4.7 logs, while P. aeruginosa could only be reduced by 0.73 log/cm2 on packaging material surface. In the final phase, the laser’s potential was preliminarily tested for sterilization of raw cow milk. The reduction patterns of E. coli, Salmonella sp. yeasts and Lactobacillus sp. were 30%, 25%, 47%, and 30%, respectively, in raw milk, moreover, laser exposure had no significant impact on physio-chemistry of milk. Therefore, results indicate the potential application of laser in packing materials and milk sterilization at the industrial level.

scholarly journals Newly isolated lactic acid bacteria from silage targeting biofilms of foodborne pathogens during milk fermentation

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Elizaveta Gavrilova ◽  
Elizaveta Anisimova ◽  
Alsu Gabdelkhadieva ◽  
Elena Nikitina ◽  
Adel Vafina ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Foodborne Pathogens ◽  
Pathogenic Bacteria ◽  
Starter Culture ◽  
Raw Milk ◽  
Raw Material ◽  
Plant Materials ◽  
Organoleptic Characteristics ◽  
Milk Fermentation

Abstract Background Raw milk, meat and plant materials are subjected to high risks of contamination by various pathogenic bacteria and thus their growth prevention is a great challenge in the food industry. Food fermentation by lactic acid bacteria (LAB) besides changing its organoleptic characteristics also helps to eliminate unfavorable microflora and represses growth of pathogens. To the date only few LABs has been reported to exhibit activity against bacteria embedded in the biofilms characterized by extreme resistance to antimicrobials, high exchange rate with resistance genes and represent high risk factor for foodborne disease development. Results Six novel LAB strains isolated from the clover silage exhibited pronounced antibacterial activity against biofilm embedded pathogens. We show explicitly that these strains demonstrate high acidification rate, completely repress the growth of E. coli, S. aureus and to a lesser extent P. aeruginosa as well as exhibit appropriate probiotic and milk-fermenting properties. Moreover, in contrast to the approved probiotic strain Lactobacillus plantarum 8PA3, the new isolates were able to efficiently eradicate preformed biofilms of these pathogens and prevent bacterial spreading originating from the biofilm. We suggest these strains as potential additives to the pre-cultures of conventional LAB strains as efficient tools targeting foodborne pathogens in order to prevent food contamination from either seeded raw material or biofilm-fouled equipment. Conclusions The AG10 strain identified as L. plantarum demonstrate attractive probiotic and milk fermentation properties as well as high resistance to simulated gastric conditions thus appearing perspective as a starter culture for the prevention of bacterial contamination originating from fouled equipment during milk fermentation.

An Overview of Molecular Stress Response Mechanisms in Escherichia coli Contributing to Survival of Shiga Toxin–Producing Escherichia coli during Raw Milk Cheese Production

2011 ◽  
Vol 74 (5) ◽  
pp. 849-864 ◽  
Author(s):  
SILVIO PENG ◽  
TAURAI TASARA ◽  
JÖRG HUMMERJOHANN ◽  
ROGER STEPHAN
Keyword(s):  
Escherichia Coli ◽  
Stress Response ◽  
Foodborne Pathogens ◽  
Stress Responses ◽  
Shiga Toxin ◽  
Pathogenic Bacteria ◽  
Raw Milk ◽  
Heat Shock Stress ◽  
Raw Milk Cheese ◽  
Cheese Production

The ability of foodborne pathogens to survive in certain foods mainly depends on stress response mechanisms. Insight into molecular properties enabling pathogenic bacteria to survive in food is valuable for improvement of the control of pathogens during food processing. Raw milk cheeses are a potential source for human infections with Shiga toxin–producing Escherichia coli (STEC). In this review, we focused on the stress response mechanisms important for allowing STEC to survive raw milk cheese production processes. The major components and regulation pathways for general, acid, osmotic, and heat shock stress responses in E. coli and the implications of these responses for the survival of STEC in raw milk cheeses are discussed.

scholarly journals Chemical Composition and Bacteriological Quality of Cow Raw Milk Collected From Daim Algarrai Area

2020 ◽  
pp. 126-133
Author(s):  
Omaima A. Madani ◽  
Telal M. Najeeb ◽  
Abdelhalim A. Hamza
Keyword(s):  
Pathogenic Bacteria ◽  
Freezing Point ◽  
Raw Milk ◽  
Cow Milk ◽  
Plate Count ◽  
Dairy Farmers ◽  
Isolation And Identification ◽  
E Coli ◽  
Milk Samples ◽  
Bacteriological Quality

This study was conducted to assess the factors influencing milk quality from dairy farmers in the Deam ALgarri aera in Sudan. A total of twenty row cow’s milk samples were collected from dairy farmers. The physicochemical parameters, bacteriological quality, milk adulteration and drug residues were assessed. The presence and enumeration of microorganisms was done based on Total Plate Count (TPC), Total Coliform Count (TCC), Total Staphylococcal count (TSC), and detection of pathogenic E. coli (O157: H7). The mean value of aerobic bacteria in the milk samples showed the higher TPC, TCC followed by TSC which were 111608 CFU/ml (log 4.95), 8145CFU/ml (log 3.42) and 6793.25 CFU/ml (log 3.29) respectively. The result of the detection of Escherichia coli O157:H7 which is a major foodborne pathogen causing severe disease in humans worldwide, all milk samples appear free from this pathogenic bacterium. The results of the physical properties of cow milk showed normal flavor, taste and colors, and higher pH (7.12), and total water (156%), the exception was the freezing point (- 0.444) and specific gravity while showed lower value (1.029) compared to SSMO limits but within FAO limits. The chemical properties of cow milk showed high amount of protein content (3.49%), lower solid not fat (SNF) which was (7.97%), Lactose (3.73%) and total solid (TS) (0.58%) when compared to both Sudanese Standard and Metrology Organization (SSMO) and Food and Agriculture Organization (FAO) standards. The result of presence or absence of antibiotic residue to the all milk samples was indicated absence antibiotic residues with (6 mm) and (7 mm) zone inhibitor against Bacillus subtilis. Isolation and identification of some pathogenic bacteria was performed according to standard methods, the results demonstrated the presence of food-borne microorganisms E. coli, klebsiela, sp, Pseudomonas sp, and Shiglla sp. with percentages of 31.1%, 29.7%, 38.4%, and 1% respectively, the presence of these bacteriological quality in the raw milk samples indicted an urgent need to implement good hygiene practices from farm to the consumer.

scholarly journals Prevalence and Characterization of Pathogenic Bacteria in Bulk Tank Raw Milk, Thailand

2020 ◽  
Vol 17 (6) ◽  
pp. 588-599
Author(s):  
Chanida KUPRADIT ◽  
Sasidhorn INNOK ◽  
Jirayus WORARATPHOKA ◽  
Mariena KETUDAT-CAIRNS
Keyword(s):  
Foodborne Pathogens ◽  
Pathogenic Bacteria ◽  
Raw Milk ◽  
Salmonella Spp ◽  
Milk Samples ◽  
Isolation And Characterization ◽  
Lack Of Information ◽  
Enterotoxin Genes ◽  
Bulk Tank

Although there are a number of raw milk collection centers in Nakhon Ratchasima, there is a lack of information with regard to the process of isolation and characterization of foodborne pathogens in raw milk. Therefore, the purpose of this research was to investigate the prevalence and characterization of foodborne pathogens, including Bacillus cereus, Escherichia coli, Listeria monocytogenes, Salmonella spp. and Staphylococcus aureus from 33 raw milk samples from 9 different raw milk collection centers located in 8 districts in Nakhon Ratchasima, Thailand. This study was conducted from January to March 2016. Results revealed that the contaminations of L. monocytogenes and Salmonella spp. were not detected in any of the raw milk samples tested. The prevalence of B. cereus, E. coli, and S. aureus in raw milk samples was found to be 9 % (10 - 2.0 ×104 CFU/ml), 42.4 and 54 % (85 - 2.7 ×104 CFU/ml), respectively. The distribution of virulence genes was tested in B. cereus and S. aureus using gene specific primers by polymerase chain reaction. Out of the 29 analyzed coagulase-positive S. aureus isolates, 27 isolates (93 %) were positive for eap gene amplification and 14 isolates (48 %) showed amplicon of eap gene and all 5 enterotoxin genes, including seG, seGV, seI, seIV, and seM genes. All 8 B. cereus isolates tested showed positive PCR result with enterotoxin FM (entFM) gene but they showed negative with hemolysin gene (hblA and hblD genes) amplifications. It was inferred from these findings that bulk tank milk is a potential source of S. aureus and B. cereus in milk.

scholarly journals Bacterian Species Identification from Raw Cow Milk Sample – A Case Study

2020 ◽  
Vol 77 (1) ◽  
pp. 25
Author(s):  
Camelia TULCAN ◽  
Amandine HORCHOLLE ◽  
Simona MARC ◽  
Jelena SAVICI ◽  
Călin MIRCU ◽  
...  
Keyword(s):  
Pathogenic Bacteria ◽  
Raw Milk ◽  
Farm Animals ◽  
Cow Milk ◽  
Resistant Bacteria ◽  
Sequencing Data ◽  
Bacterial Strains ◽  
Laboratory Procedure ◽  
Milk Samples ◽  
Mastitic Milk

The raw milk can support a wide variety of microbiota, due to its high nutritional content. These microorganisms become from a variety of sources and in farm animals and can cause serious damage by infecting the mammary glands and causing mastitis. The mastitic milk is an important source of disease among the consumers. In this paper, we present a study case of pathogenic bacteria identification by DNA based methods from raw milk samples which were collected from farm cows with severe recurrent mastitis. Previously it was diagnosticated that multidrug resistant bacteria E. coli strains are causing those infections. The laboratory procedure consisted of isolation of DNA from raw cow milk samples, followed by PCR based bacterial identification and DNA sequencing. Data collected from sequencing experiment were aligned against reference sequences from bacterial strains. In our study it was found that Pseudomonas aeruginosa, is present in the mastitic milk samples.

scholarly journals Bacterial Quality, Prevalence of Pathogens, and Molecular Characterization of Biofilm-Producing Staphylococcus aureus from Korean Dairy Farm Environments

Animals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1306
Author(s):  
Sangdon Ryu ◽  
Minhye Shin ◽  
Bohyun Yun ◽  
Woongji Lee ◽  
Hyejin Choi ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Foodborne Pathogens ◽  
Biofilm Formation ◽  
Bacterial Infections ◽  
Pathogenic Bacteria ◽  
Dairy Farm ◽  
Dairy Farms ◽  
Raw Milk ◽  
Processing Plant ◽  
Microbiological Analysis

Raw milk acts as a mediator of major foodborne pathogenic bacterial infections. However, the sources of pathogens that contaminate milk are often unclear. This study assessed the prevalence of sanitary quality-indicating bacteria (total aerobic bacteria, psychrotrophic bacteria, coliform, and yeast/molds), including seven foodborne pathogens, in a dairy farm environment and processing plant in Korea. The microbiological analysis showed that a few sites, such as vat bottoms, room floors, drain holes, and niches, showed high microbial loads in most dairy farms. Based on quantitative microbial tests, Bacillus cereus was detected in three farms and Staphylococcus aureus was detected in only one farm. Among them, S. aureus JDFM SA01 isolated from a milk filter showed strong biofilm formation and toxicity to the host Caenorhabditis elegans. Subsequently, RNA-seq was performed to characterize the biofilm formation ability of S. aureus JDFM SA01. In biofilms, the significant upregulation of genes encoding microbial surface components and recognizing adhesive matrix molecules promotes adhesion might explain the increased viability and biomass of biofilms. This study provided insight into the prevalence of pathogenic bacteria and microbial contamination levels across dairy farms.

An Easy Efficient Method of Veterinary Drug Residue Analysis in Raw Milk by RP-HPLC-UV with Application to Raw Milk

2020 ◽  
Vol 16 (7) ◽  
pp. 942-949
Author(s):  
Lekweiri Haiba Legrae ◽  
Mohamed Fadel Deida ◽  
Bah Mohamed Lemine Abdellahi ◽  
Mohamed Brahim Elkory ◽  
Ibrahima Ndiaye ◽  
...  
Keyword(s):  
Residue Analysis ◽  
Raw Milk ◽  
Cow Milk ◽  
Veterinary Drug ◽  
Easy Method ◽  
Rp Hplc ◽  
Peak Resolution ◽  
European Standards ◽  
Moderate Cost ◽  
Short Time

Background: This study reports an easy method of a veterinary drug investigation in raw milk, based on QuECHERS extraction followed by RP-HPLC-UV analysis. Use of this benchtop system was motivated by its availability and moderate cost relatively to other sophisticated methods such as LC-MS which are more efficient. Methods: This developed method has been optimized and then after validation according to EU legislation, it demonstrated good linearity with R²>0.997, acceptable peak resolution within a short time (<9.5 min) and good recovery of the analyzed drugs (OXY, ALZ and IVR, respectively 87.08, 99.02 and 92.01 %). Additionally, we applied the method to the analysis of cow milk, collected in Nouakchott, capital of Mauritania. Results: The obtained results indicated a mixed level of drug use according to targeted molecules. In 42% of sampled farms, the anti-parasitics IVR and ALZ were detected whereas the antibiotic OXY was detected in 50%. Conclusion: This investigation shows that 17% of the sampled farms exceeded European standards for IVR drug.

scholarly journals In silico characterization and structural modeling of bacterial metalloprotease of family M4

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Rajnee Hasan ◽  
Md. Nazmul Haq Rony ◽  
Rasel Ahmed
Keyword(s):  
Drug Targets ◽  
Active Sites ◽  
Pathogenic Bacteria ◽  
Tertiary Structure ◽  
Transmembrane Helix ◽  
Confidence Score ◽  
Potential Drug ◽  
Protein Protein Interaction ◽  
Industrial Level ◽  
Potential Drug Targets

Abstract Background The M4 family of metalloproteases is comprised of a large number of zinc-containing metalloproteases. A large number of these enzymes are important virulence factors of pathogenic bacteria and therefore potential drug targets. Whereas some enzymes have potential for biotechnological applications, the M4 family of metalloproteases is known almost exclusively from bacteria. The aim of the study was to identify the structure and properties of M4 metalloprotease proteins. Results A total of 31 protein sequences of M4 metalloprotease retrieved from UniProt representing different species of bacteria have been characterized for various physiochemical properties. They were thermostable, hydrophillic protein of a molecular mass ranging from 38 to 66 KDa. Correlation on the basis of both enzymes and respective genes has also been studied by phylogenetic tree. B. cereus M4 metalloprotease (PDB ID: 1NPC) was selected as a representative species for secondary and tertiary structures among the M4 metalloprotease proteins. The secondary structure displaying 11 helices (H1-H11) is involved in 15 helix-helix interactions, while 4 β-sheet motifs composed of 15 β-strands in PDBsum. Possible disulfide bridges were absent in most of the cases. The tertiary structure of B. cereus M4 metalloprotease was validated by QMEAN4 and SAVES server (Ramachandran plot, verify 3D, and ERRAT) which proved the stability, reliability, and consistency of the tertiary structure of the protein. Functional analysis was done in terms of membrane protein topology, disease-causing region prediction, proteolytic cleavage sites prediction, and network generation. Transmembrane helix prediction showed absence of transmembrane helix in protein. Protein-protein interaction networks demonstrated that bacillolysin of B. cereus interacted with ten other proteins in a high confidence score. Five disorder regions were identified. Active sites analysis showed the zinc-binding residues—His-143, His-147, and Glu-167, with Glu-144 acting as the catalytic residues. Conclusion Moreover, this theoretical overview will help researchers to get a details idea about the protein structure and it may also help to design enzymes with desirable characteristics for exploiting them at industrial level or potential drug targets.

scholarly journals The Use of Bacteriophages in the Poultry Industry

Animals ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 872 ◽  
Author(s):  
Katarzyna Żbikowska ◽  
Monika Michalczuk ◽  
Beata Dolka
Keyword(s):  
Foodborne Pathogens ◽  
Pathogenic Bacteria ◽  
Bacterial Resistance ◽  
Health And Safety ◽  
Legal Framework ◽  
Multidrug Resistant ◽  
Poultry Production ◽  
Salmonella Spp ◽  
Food Contact Surfaces ◽  
Public Health And Safety

The emergence of multidrug-resistant infections and antibiotic failures have raised concerns over human and veterinary medicine worldwide. Poultry production has had to confront the problems of an alarming increase in bacterial resistance, including zoonotic pathogens. According to the European Food Safety Authority (EFSA), campylobacteriosis and salmonellosis have been the most frequently reported human foodborne diseases linked to poultry. This situation has strongly stimulated a renewal of scientists’ interest in bacteriophages (phages) since the beginning of the 21st century. Bacteriophages are the viruses of bacteria. They are abundant in nature, and accompany bacteria in each environment they colonize, including human microbiota. In this review, we focused on the use of bacteriophages as therapeutic agents to treat infections and reduce counts of pathogenic bacteria in poultry, as biocontrol agents to eliminate foodborne pathogens on/in food, and also as disinfectants to reduce contamination on food-contact surfaces or poultry carcasses in industrial conditions. Most of the phage-based products are targeted against the main foodborne pathogens, such as Campylobacter jejuni, Salmonella spp., Escherichia coli, Listeria monocytogenes, Staphylococcus aureus, and Clostridium perfringens. Phages are currently addressed at all stages of the poultry production "from farm to fork", however, their implementation into live birds and food products still provokes discussions especially in the context of the current legal framework, limitations, as well as public health and safety.

Insects as vectors of foodborne pathogenic bacteria

2011 ◽  
Vol 4 (1) ◽  
pp. 5-16 ◽  
Author(s):  
Jeffrey Blazar ◽  
Marc Allard ◽  
E. Kurt Lienau
Keyword(s):  
Food Safety ◽  
Foodborne Pathogens ◽  
Pathogenic Bacteria ◽  
Current Knowledge ◽  
Disease Outbreaks ◽  
House Fly ◽  
American Cockroach ◽  
Health Concern ◽  
Foodborne Disease ◽  
Salmonella Spp

AbstractFood safety is an important consideration worldwide. To maintain and improve our current knowledge of foodborne disease outbreaks, we must understand some of the more imminent issues related to food safety. A variety of agents are responsible for transmitting the estimated 76 million cases of illnesses caused by foodborne pathogens every year. This review explores why insects pose a serious health concern, in terms of worldwide food safety initiatives, by looking at evidence in published <abs>Food safety is an important consideration worldwide. To maintain and improve our current knowledge of foodborne disease outbreaks, we must understand some of the more imminent issues related to food safety. A variety of agents are responsible for transmitting the estimated 76 million cases of illnesses caused by foodborne pathogens every year. This review explores why insects pose a serious health concern, in terms of worldwide food safety initiatives, by looking at evidence in published literature. We highlight at least eleven different species of insects, including the lesser mealworm, Alphitobius diaperinus (Panzer); secondary screwworm, Cochliomyia macellaria (Fabricius); synanthropic flies [flesh fly, Sarcophaga carnaria (L.); house fly, Musca domestica (L.); fruit fly, Drosophila melanogaster (Meigen); and stable fly, Stomoxys calcitrans (L.)], American cockroach, Periplaneta americana (L.); German cockroach, Blatella germanica (L.); Oriental cockroach, Blatta orientalis (L.); Pacific beetle cockroach, Diploptera punctata (Eschscholtz); and Speckled feeder cockroach, Nauphoeta cinerea (Olivier), which act as vectors for Salmonella spp. or Escherichia coli and illustrate how these insects are successful vectors of foodborne disease outbreaks. We propose that insects be considered as one of the latest issues in food safety initiatives. Not only are some insects extremely important contributors to diseases, but now we suggest that more research into insects as potential carriers of E. coli and Salmonella spp., and therefore as contributing to foodborne disease outbreaks, is granted.

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