scholarly journals Inactivation of Bacteria Using Bioactive Nanoparticles and Alternating Magnetic Fields

Nanomaterials ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 342
Author(s):  
Vitalij Novickij ◽  
Ramunė Stanevičienė ◽  
Rūta Gruškienė ◽  
Kazimieras Badokas ◽  
Juliana Lukša ◽  
...  
Keyword(s):  
Magnetic Fields ◽  
Foodborne Pathogens ◽  
Morphological Changes ◽  
Foodborne Pathogen ◽  
Cellular Damage ◽  
Suitable Model ◽  
Log Reduction ◽  
Invasive Infections ◽  
Alternating Magnetic Fields ◽  
Inactivation Of Bacteria

Foodborne pathogens are frequently associated with risks and outbreaks of many diseases; therefore, food safety and processing remain a priority to control and minimize these risks. In this work, nisin-loaded magnetic nanoparticles were used and activated by alternating 10 and 125 mT (peak to peak) magnetic fields (AMFs) for biocontrol of bacteria Listeria innocua, a suitable model to study the inactivation of common foodborne pathogen L. monocytogenes. It was shown that L. innocua features high resistance to nisin-based bioactive nanoparticles, however, application of AMFs (15 and 30 min exposure) significantly potentiates the treatment resulting in considerable log reduction of viable cells. The morphological changes and the resulting cellular damage, which was induced by the synergistic treatment, was confirmed using scanning electron microscopy. The thermal effects were also estimated in the study. The results are useful for the development of new methods for treatment of the drug-resistant foodborne pathogens to minimize the risks of invasive infections. The proposed methodology is a contactless alternative to the currently established pulsed-electric field-based treatment in food processing.

Evaluation of foodborne pathogen die-off in back-sweetened wine and apple cider models

2021 ◽  
Author(s):  
Zirui Ray Xiong ◽  
Anqi Chen ◽  
Glycine Zhujun Jiang ◽  
Alisha G Lewis ◽  
Christine D Sislak ◽  
...  
Keyword(s):  
Foodborne Pathogens ◽  
Apple Juice ◽  
Foodborne Pathogen ◽  
Grape Juice ◽  
White Wine ◽  
Low Ph ◽  
Alcoholic Beverages ◽  
Pathogen Inactivation ◽  
Apple Cider ◽  
Log Reduction

Wine and alcoholic apple cider are commonly back-sweetened with unpasteurized juice to produce fresh, natural, and palatable sweetened alcoholic beverages. Foodborne pathogens may be introduced from unpasteurized juice into alcoholic beverages through this back-sweetening process. Although pathogens generally do not survive under low pH conditions or high alcohol environment, the die-off of these pathogens has not been established to ensure the safety of the products. To determine the safety of these back-sweetened beverages, we evaluated the survival of three common foodborne pathogens, E. coli O157:H7, Salmonella enterica , and Listeria monocytogenes in modified white grape juice and apple juice models. White grape juice and apple juice were modified with hydrochloric acid/sodium hydroxide and ethanol to achieve conditions that are similar to the back-sweetened white wine and alcoholic apple cider. Pathogen cocktails were inoculated separately into modified juice models and their survival in the juice models were recorded over a 96-hour period. Our results show that a combination of low pH and high ethanol content resulted in a faster pathogen die-off compared to higher pH and lower ethanol conditions. The holding times required for different combinations of pH and ethanol concentration for each juice model to achieve 5-log reduction were reported. This research provides data to validate pathogen die-off to comply with Juice HACCP 5-log pathogen inactivation requirements for back-sweetened wine and alcoholic apple cider.

scholarly journals Efficacy of household washing pre-treatments and cooking methods for reduction of Listeria monocytogenes in artificially contaminated chicken offal

Food Research ◽  
2019 ◽  
Vol 4 (1) ◽  
pp. 166-174
Author(s):  
Chee Hao Kuan ◽  
Son Radu ◽  
Nor Ainy Mahyudin ◽  
John Yew Huat Tang ◽  
Siok Koon Yeo ◽  
...  
Keyword(s):  
Listeria Monocytogenes ◽  
Water Flow ◽  
Foodborne Pathogens ◽  
Tap Water ◽  
Water Flow Rate ◽  
Foodborne Pathogen ◽  
Cooking Methods ◽  
Deep Frying ◽  
Log Reduction ◽  
Handling Practices

Consumption of chicken offal is common and famous among Malaysians as it is often served as one of the side dishes with rice. Chicken offal can be a potential source of Listeria monocytogenes because slaughtered animals are recognized as a reservoir for foodborne pathogens. L. monocytogenes is a dangerous foodborne pathogen which can cause severe foodborne listeriosis with high fatality rate. This study aimed to determine the efficacy of different washing pre-treatment and cooking methods to reduce L. monocytogenes in artificially contaminated chicken offal. All the washing pre-treatments (dip treatment in different water sources and wash treatment with different water flow rates) showed significant reduction of the pathogen (p<0.05) when the inoculated samples were treated from 2 mins onwards. Washing the inoculated samples under the water flow rate of 2 L/min was the most effective way to reduce the number of L. monocytogenes (approximately 1.97 log reduction after washing for 10 mins). For heat treatment study, deep-frying was the most effective cooking method followed by boiling and pan-frying to reduce L. monocytogenes where all L. monocytogenes cells (7.91 log10 CFU/g) were killed within 45 s under deep-frying treatment. Overall, the study indicated that washing under running tap water (2 L/min) and deep-frying was effective in reducing and controlling the microbial populations during food preparation. The findings from this study can serve as a safe preparation step and cooking guideline. It is necessary to implement safe steps in food handling practices among food handlers to minimize the risk of foodborne infection.

Measuring Magnetic Permeability of Monolithic Annular Measures in Alternating Magnetic Fields

2019 ◽  
Vol 55 (11) ◽  
pp. 851-857 ◽  
Author(s):  
V. A. Syas’ko ◽  
S. S. Golubev ◽  
Ya. G. Smorodinskii ◽  
P. V. Solomenchuk ◽  
E. B. Bryukhovetskaya
Keyword(s):  
Magnetic Fields ◽  
Magnetic Permeability ◽  
Alternating Magnetic Fields

Modulation of cardiac rhythm in the humans exposed to extremely weak alternating magnetic fields

BIOPHYSICS ◽  
2008 ◽  
Vol 53 (6) ◽  
pp. 648-654 ◽  
Author(s):  
V. V. Lednev ◽  
N. A. Belova ◽  
A. M. Ermakov ◽  
E. B. Akimov ◽  
A. G. Tonevitsky
Keyword(s):  
Magnetic Fields ◽  
Cardiac Rhythm ◽  
Alternating Magnetic Fields

Magnetocaloric properties of manganites in alternating magnetic fields

JETP Letters ◽  
2010 ◽  
Vol 90 (10) ◽  
pp. 663-666 ◽  
Author(s):  
A. M. Aliev ◽  
A. B. Batdalov ◽  
V. S. Kalitka
Keyword(s):  
Magnetic Fields ◽  
Magnetocaloric Properties ◽  
Alternating Magnetic Fields

Thermal Energy Dissipation by SiO2-Coated Plasmonic-Superparamagnetic Nanoparticles in Alternating Magnetic Fields

2013 ◽  
Vol 25 (22) ◽  
pp. 4603-4612 ◽  
Author(s):  
Georgios A. Sotiriou ◽  
Michelle A. Visbal-Onufrak ◽  
Alexandra Teleki ◽  
Eduardo J. Juan ◽  
Ann M. Hirt ◽  
...  
Keyword(s):  
Energy Dissipation ◽  
Magnetic Fields ◽  
Thermal Energy ◽  
Superparamagnetic Nanoparticles ◽  
Thermal Energy Dissipation ◽  
Alternating Magnetic Fields

Utilizing the Public GenomeTrakr Database for Foodborne Pathogen Traceback v1

2021 ◽  
Author(s):  
Ruth E Timme ◽  
Maria Sanchez ◽  
Marc Allard
Keyword(s):  
Real Time ◽  
Foodborne Pathogens ◽  
Pathogen Detection ◽  
Foodborne Pathogen ◽  
Reference Database ◽  
Surveillance Program ◽  
Environmental Isolates ◽  
The Public ◽  
The World ◽  
The Usa

This protocol outlines the all the steps necessary to become a GenomeTrakr data contributor. GenomeTrakr is an international genomic reference database of mostly food and environmental isolates from foodborne pathogens. The data and analyses are housed at the National Center for Biotechnology Information (NCBI), which is a database freely available to anyone in the world. The Pathogen Detection browser at NCBI computes daily cluster results adding the newly submitted data to the existing phylogenetic clusters of closely related genomes. Contributors to this database can see how their new isolates are related to the real-time foodborne pathogen surveillance program established in the USA and a few other countries, and at the same time adding valuable new data to the reference database. ------ Although originally published as a Chapter in Methods and Protocols, Foodborne Bacterial Pathogens, the protocol has since been adapted and split into four separate protocols all of which are contained in this collection.

scholarly journals Baicalein Inhibits Stx1 and 2 of EHE: Effects of Baicalein on the Cytotoxicity, Production, and Secretion of Shiga Toxins of Enterohaemorrhagic Escherichia coli

Toxins ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 505 ◽  
Author(s):  
Vinh ◽  
Shinohara ◽  
Yamada ◽  
Duc ◽  
Nakayama ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Foodborne Pathogens ◽  
Antibacterial Agent ◽  
Foodborne Pathogen ◽  
Vero Cells ◽  
In Silico Screening ◽  
Shiga Toxins ◽  
Enterohaemorrhagic Escherichia Coli ◽  
Compound Database ◽  
Real Time Qpcr

Shiga toxin-producing enterohaemorrhagic Escherichia coli (EHEC) O157:H7 is an important foodborne pathogen. Baicalein (5,6,7-trihydroxylflavone), a flavone isolated from the roots of Scutellaria baicalensis, is considered as a potential antibacterial agent to control foodborne pathogens. Among seven compounds selected by in silico screening of the natural compound database, baicalein inhibited the cytotoxicity of both Shiga toxins 1 and 2 (Stx1 and Stx2) against Vero cells after pretreatment at 0.13 mmol/L. In addition, baicalein reduced the susceptibility of Vero cells to both Stx1 and Stx2. Real-time qPCR showed that baicalein increased transcription of stx1 but not of stx2. However, baicalein had no effects on production or secretion of Stx1 or Stx2. Docking models suggested that baicalein formed a stable structure with StxB pentamer with low intramolecular energy. The results demonstrate that inhibitory activity of baicalein against the cytotoxicity of both Stx1 and Stx2 might be due to of the formation of a binding structure inside the pocket of the Stx1B and Stx2B pentamers.

HORMONE REPLACEMENT THERAPY IN THE MENOPAUSE: A SUITABLE ANIMAL MODEL

1979 ◽  
Vol 83 (1) ◽  
pp. 67-77 ◽  
Author(s):  
LUCIENNE PAPADAKI ◽  
J. O. W. BEILBY ◽  
JANINA CHOWANIEC ◽  
W. F. COULSON ◽  
A. J. DARBY ◽  
...  
Keyword(s):  
Hormone Replacement Therapy ◽  
Replacement Therapy ◽  
Morphological Changes ◽  
Hormone Replacement ◽  
Serum Levels ◽  
Suitable Model ◽  
Treatment Groups ◽  
Oestrone Sulphate ◽  
Suitable Animal Model ◽  
Cellular Metabolic Activity

SUMMARY Female CBA mice, aged 11 months, were treated cyclically with oral ethynyl oestradiol or oestrone sulphate for 3 months. The ovaries of all animals appeared to be atrophied. Target tissues throughout the genital tract showed a response to both oestrogens. Electron microscopy of both the endometrium and the urothelium demonstrated morphological changes characteristic of increased cellular metabolic activity in the treated mice. Endometrial hyperplasia developed in both treatment groups but more pronounced epithelial changes occurred with oestrone sulphate. This hyperplasia was accompanied by a doubling in the number of uterine cytoplasmic oestrogen receptors. A 50% fall in serum levels of luteinizing hormone in the treated mice revealed that the hypothalamic-pituitary system was still intact. Both oestrogens improved skeletal balance by changes in cortical-endosteal bone remodelling. The results suggest that the CBA strain of mouse is a suitable model for the study of the human climacteric and its response to hormone replacement therapy.

Effect of Oxygen Stress on Growth and Survival of Clostridium perfringens, Campylobacter jejuni, and Listeria monocytogenes under Different Storage Conditions

2015 ◽  
Vol 78 (4) ◽  
pp. 691-697 ◽  
Author(s):  
HAMZAH AL-QADIRI ◽  
SHYAM S. SABLANI ◽  
MAHMOUDREZA OVISSIPOUR ◽  
NIVIN AL-ALAMI ◽  
BYJU GOVINDAN ◽  
...  
Keyword(s):  
Listeria Monocytogenes ◽  
Campylobacter Jejuni ◽  
Clostridium Perfringens ◽  
Foodborne Pathogens ◽  
Storage Conditions ◽  
Growth And Survival ◽  
Anoxic Conditions ◽  
Initial Inoculum ◽  
Log Reduction ◽  
Packaged Food

This study investigated the growth and survival of three foodborne pathogens (Clostridium perfringens, Campylobacter jejuni, and Listeria monocytogenes) in beef (7% fat) and nutrient broth under different oxygen levels. Samples were tested under anoxic (&lt;0.5%), microoxic (6 to 8%), and oxic (20%) conditions during storage at 7°C for 14 days and at 22°C for 5 days. Two initial inoculum concentrations were used (1 and 2 log CFU per g of beef or per ml of broth). The results show that C. perfringens could grow in beef at 22°C, with an increase of approximately 5 log under anoxic conditions and a 1-log increase under microoxic conditions. However, C. perfringens could not survive in beef held at 7°C under microoxic and oxic storage conditions after 14 days. In an anoxic environment, C. perfringens survived in beef samples held at 7°C, with a 1-log reduction. A cell decline was observed at 2 log under these conditions, with no surviving cells at the 1-log level. However, the results show that C. jejuni under microoxic conditions survived with declining cell numbers. Significant increases in L. monocytogenes (5 to 7 log) were observed in beef held at 22°C for 5 days, with the lowest levels recovered under anoxic conditions. L. monocytogenes in refrigerated storage increased by a factor of 2 to 4 log. It showed the greatest growth under oxic conditions, with significant growth under anoxic conditions. These findings can be used to enhance food safety in vacuum-packed and modified atmosphere–packaged food products.

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