Binding and mutagenicity studies with 3-nitrosofluorene on Salmonella typhimurium TA98 grown at different temperatures

1980 ◽  
Vol 69 (2) ◽  
pp. 231-239 ◽  
Author(s):  
Michael J. Hampton ◽  
Robert A. Floyd ◽  
J.Bennett Clark ◽  
John H. Lancaster
Keyword(s):  
Salmonella Typhimurium ◽  
Different Temperatures

The Longevity of Polyclonal Antibody to Salmonella typhimurium at Different Temperatures on a Magnetostrictive Sensor Platform

2012 ◽  
Vol 1 (1) ◽  
pp. 25-30
Author(s):  
Jing Hu ◽  
Rajesh Guntupalli ◽  
Ramji S. Lakshmanan ◽  
Bryan A. Chin
Keyword(s):  
Salmonella Typhimurium ◽  
Polyclonal Antibody ◽  
Sensor Platform ◽  
Different Temperatures ◽  
Magnetostrictive Sensor

scholarly journals Mutagenic Potential of Artificial Athletic Field Crumb Rubber at Increased Temperatures

2015 ◽  
Vol 115 (2) ◽  
pp. 32 ◽  
Author(s):  
Michael J. Dorsey ◽  
Elizabeth Anderson ◽  
Oliva Ardo ◽  
Max Chou ◽  
Edward Farrow ◽  
...  
Keyword(s):  
Surface Temperature ◽  
Salmonella Typhimurium ◽  
Ambient Temperature ◽  
Ames Test ◽  
Crumb Rubber ◽  
Water Soluble ◽  
Mutagenic Potential ◽  
Athletic Fields ◽  
Athletic Field ◽  
Different Temperatures

Rubber tires contain several compounds that are known or suspected carcinogens.  Many carcinogens are mutagens, and fluctuation assays based on the Ames test can be used as an initial screen for mutagenic potential.  Granulated crumb rubber from recycled tires is commonly used in the creation of artificial athletic fields, and the surface temperature of these fields can reach levels far above the ambient temperature.  In this study, crumb rubber samples taken directly from four separate artificial athletic field surfaces were used to make leachates using water at different temperatures.  For each of these fields, leachates obtained in water at 70 ºC showed significant mutagenic potential (p ≤ .001) in Salmonella typhimurium fluctuation assays.  Leachates obtained in water at 40 ºC showed no mutagenic potential for any of the fields tested.  For one field, crumb rubber heated in water at temperatures as low as 50 ºC resulted in significant mutagenic potential (p ≤ 0.001).  Water used in an experiment designed to mimic the irrigation of an artificial athletic field also showed mutagenic potential (p ≤ 0.001) in a fluctuation assay.  These results suggest that at the higher temperatures that can exist on artificial athletic field surfaces, the crumb rubber infill on these artificial athletic fields can become the source of a water soluble agent with mutagenic potential in bacteria.

Evaluation of the Microbiological Safety of Tempeh Made from Unacidified Soybeans

1985 ◽  
Vol 48 (5) ◽  
pp. 438-441 ◽  
Author(s):  
NOBUMASA TANAKA ◽  
SUSAN K. KOVATS ◽  
JEAN A. GUGGISBERG ◽  
LOUISE M. MESKE ◽  
MICHAEL P. DOYLE
Keyword(s):  
Staphylococcus Aureus ◽  
Salmonella Typhimurium ◽  
Yersinia Enterocolitica ◽  
Clostridium Botulinum ◽  
Bacterial Pathogens ◽  
Rhizopus Oligosporus ◽  
Microbiological Safety ◽  
Staphylococcal Enterotoxins ◽  
Different Temperatures ◽  
High Level

Studies were done to evaluate the safety of tempeh made from unacidifed soybeans and inoculated with different bacterial pathogens. Pathogens were added to either the soybeans before fermentation by Rhizopus oligosporus or the tempeh after fermentation and steaming. In the latter method, the inoculated products were incubated at several different temperatures (5, 10, 15 and 25°C). Clostridium botulinum (types A and/or B) toxin was produced in 2 d during the fermentation and within 5 d at 25°C or 4 wk at 15°C in tempeh inoculated and incubated in vacuum packages after fermentation and steaming. Staphylococcus aureus grew very well (>6-log10 CFU/g increase) in 2 d during the fermentation, and grew from ca. 103 CFU/g to 108 CFU/g in 7 d at 25°C and 21 d at 15°C in tempeh inoculated after fermentation and steaming. Staphylococcal enterotoxins were detected in some of these samples. Salmonella typhimurium also grew well during the fermentation (>6-log10 CFU/g increase in 1 d), but grew relatively slowly at 25 and 15°C in tempeh inoculated after fermentation and steaming. Yersinia enterocolitica grew very well (>6-log10 CFU/g increase) in 1 d during the fermentation, and also grew well in tempeh inoculated after fermentation and steaming, with a >6 log10 CFU/g increase in 2 d at 25 or 15°C and 5 d at 10°C. Results of these studies indicate the need for maintaining: (a) a high level of sanitary practices during production and (b) good refrigeration (≤5°C) of the product following fermentation until it is used.

Attachment of Salmonella typhimurium to Skins of Chicken Scalded at Various Temperatures

1993 ◽  
Vol 56 (8) ◽  
pp. 661-665 ◽  
Author(s):  
JEONG-WEON KIM ◽  
MIKE F. SLAVIK ◽  
CARL L. GRIFFIS ◽  
JOEL T. WALKER
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Salmonella Typhimurium ◽  
Skin Surface ◽  
Transmission Electron ◽  
Significant Difference ◽  
Plating Method ◽  
Different Temperatures ◽  
Skin Morphology ◽  
Scanning Electron

Microtopography of chicken skin was studied by varying scalding temperature to determine the least favorable skin surface for salmonellae attachment. Birds were scalded at 52, 56, and 60°C, and the changes of skin morphology were examined by light and transmission electron microscopy throughout the whole processing. Breast skins obtained immediately after picking were inoculated with Salmonella typhimurium, and the attachment was quantified by using scanning electron microscopy and microbiological plating techniques. Skins scalded at 52 and 56°C retained most of the epidermis, although the latter temperature caused the loss of twice as much stratum corneum layers and produced a smoother surface than the former. Skins at 60°C began to lose most of epidermal layers during scalding and exposed dermal surface after picking, which was sometimes covered with thin fragmental epidermis or basal tissue. The number of salmonellae attached to 60°C-processed skins was 1.1~1.3 logs higher than those attached to the skins processed at 52 and 56°C, as measured by scanning electron microscopy. Microbiological plating, however, showed no significant difference in attachment among three skins processed at different temperatures. This was probably due to the insensitivity of the plating method to differentiate attachment strengths of salmonellae to the skin. The above results suggest that removal of whole epidermis should be avoided in processing to reduce salmonellae attachment to the skin.

Evaluation of the Microbiological Safety of Tofu

1984 ◽  
Vol 47 (8) ◽  
pp. 618-622 ◽  
Author(s):  
SUSAN K. KOVATS ◽  
MICHAEL P. DOYLE ◽  
NOBUMASA TANAKA
Keyword(s):  
Staphylococcus Aureus ◽  
Salmonella Typhimurium ◽  
Yersinia Enterocolitica ◽  
Clostridium Botulinum ◽  
Toxin Production ◽  
Staphylococcal Enterotoxin ◽  
Microbiological Safety ◽  
Botulinum Type ◽  
Different Temperatures ◽  
High Level

Studies were done to evaluate the safety of tofu inoculated with different bacterial pathogens and held at different temperatures. Clostridium botulinum (type A and/or B) toxin was produced in tofu after 1 and 3 wk of storage at 25 and 15°C, respectively, but not within 6 wk at 5 or 10°C. Compared with water-packed tofu, vacuum-packaged tofu did not increase the risk of botulinal toxin production at 15°C. Staphylococcus aureus and Salmonella typhimurium grew at similar rates at 10, 15 and 25°C, but decreased in number at 5°C. Staphylococcal enterotoxin was not produced within 4 wk at 10°C, 8 d at 15°C, or 2 d at 25°C, even though an S. aureus population of >107 CFU/g was present in most samples analyzed. Staphylococcal enterotoxin was detected in a 5-d sample held at 25°C. Toxin production may have been delayed because of the low amount of oxygen in water-packed tofu. Yersinia enterocolitica grew at all temperatures evaluated (5, 10, 15 and 25°C), including a 4- to 6-log10 increase within 14 d at 5°C. Results of these studies substantiate the need for: (a) implementing a high level of sanitary practices during tofu production, (b) pasteurizing tofu after packaging, and (c) properly refrigerating tofu during storage and display.

Predictive Model for Growth of Staphylococcus aureus on Raw Pork, Ham, and Sausage

2016 ◽  
Vol 79 (1) ◽  
pp. 132-137 ◽  
Author(s):  
AHMAD ROIS MANSUR ◽  
JOONG-HYUN PARK ◽  
DEOG-HWAN OH
Keyword(s):  
Staphylococcus Aureus ◽  
Salmonella Typhimurium ◽  
Storage Temperature ◽  
Microbial Risk ◽  
Pork Products ◽  
Poultry Products ◽  
Root Model ◽  
Different Types ◽  
Different Temperatures ◽  
Temperature Ranges

ABSTRACT Recent Staphylococcus aureus outbreaks linked to meat and poultry products underscore the importance of understanding the growth kinetics of S. aureus in these products at different temperatures. Raw pork, ham, and sausage (each 10 ± 0.3 g) were inoculated with a three-strain cocktail of S. aureus, resulting in an initial level of ca. 3 log CFU/g. Samples were stored isothermally at 10, 15, 20, 25, 30, 35, and 40°C, and S. aureus was enumerated at appropriate time intervals. The square root model was developed using experimental data collected from S. aureus grown on all samples (where data from raw pork, ham, and sausage were combined) so as to describe the growth rate of S. aureus as a function of temperature. The model was then compared with models for S. aureus growth on each individual sample in the experiments (raw pork, ham, or sausage) and the S. aureus ComBase models, as well as models for the growth of different types of pathogens (S. aureus, Escherichia coli O157:H7, Clostridium perfringens, Salmonella serovars, and Salmonella Typhimurium) on various types of meat and poultry products. The results show that the S. aureus model developed here based on the pooled data from all three pork products seems suitable for the prediction of S. aureus growth on different pork products under isothermal conditions from 10 to 25°C, as well as for S. aureus growth on different meat and poultry products at higher temperatures between 20 and 35°C. Regardless of some high deviations observed at temperatures between 25 and 40°C, the developed model still seems suitable to predict the growth of other pathogens on different types of meat and poultry products over the temperature ranges used here, especially for E. coli O157:H7 and Salmonella Typhimurium. The developed model, therefore, may be useful for estimating the effects of storage temperature on the behavior of pathogens in different meat and poultry products and for microbial risk assessments evaluating meat safety.

Growth Inhibition and Alternation of Virulence Genes of Salmonella on Produce Products Treated with Polyphenolic Extracts from Berry Pomace

2020 ◽  
Vol 83 (8) ◽  
pp. 1463-1471
Author(s):  
ZABDIEL ALVARADO-MARTINEZ ◽  
ZAJEBA TABASHSUM ◽  
SERAJUS SALAHEEN ◽  
CHRISTINE MUI ◽  
ALEX LEBOVIC ◽  
...  
Keyword(s):  
Salmonella Typhimurium ◽  
Virulence Genes ◽  
Bacterial Load ◽  
The United States ◽  
Farmers Markets ◽  
Relative Expression ◽  
Treatment Conditions ◽  
Increased Risk ◽  
Different Temperatures ◽  
Live Bacteria

ABSTRACT Organic farming, including integrated crop–livestock farms and backyard farming, is gaining popularity in the United States, and products from these farms are commonly sold at farmers' markets, local stores, and roadside stalls. Because organic farms avoid using antibiotics and chemicals and because they use composted animal waste and nonprofessional harvesting and packaging methods, their products have an increased risk of cross-contamination with zoonotic pathogens. This study sets out to evaluate the efficiency of new postharvest disinfection processes using natural berry pomace extracts (BPEs) as a means to reduce the bacterial load found in two common leafy greens, spinach and celery. Spinach and celery were inoculated with a fixed bacterial load of Salmonella Typhimurium and later were soaked in BPE-supplemented water (wBPE) for increasing periods of time, at two different temperatures (24 and 4°C). The remaining live bacteria were quantified (log CFU per leaf), and numbers were compared with those on vegetables soaked in water alone. The relative expression of virulence genes (hilA1/C1/D1, invA1/C1/E1/F1) of wBPE-treated Salmonella Typhimurium was determined. For spinach, there was a significant (P < 0.05) reduction of Salmonella Typhimurium: 0.2 to 1.2 log CFU/mL and 0.5 to 5 log CFU/mL at 24 and 4°C, respectively. For celery, there was also a significant (P < 0.05) reduction of Salmonella Typhimurium at either 24 or 4°C. The changes in relative expression of virulence genes of Salmonella Typhimurium isolated from spinach and celery varied depending on the treatment conditions but showed a significant down-regulation of inv genes when treated at 24°C for 1,440 min (P < 0.05). After seven uses, the total polyphenolic compounds in wBPE remained at an effective concentration. This research suggests that soaking these vegetables with BPE-containing water at lower temperatures can still reduce the Salmonella Typhimurium load enough to minimize the risk of infection and alter virulence properties. HIGHLIGHTS

The Longevity of Polyclonal Antibody to Salmonella typhimurium at Different Temperatures on a Magnetostrictive Sensor Platform

2012 ◽  
Vol 1 (1) ◽  
pp. 25-30
Author(s):  
Jing Hu ◽  
Rajesh Guntupalli ◽  
Ramji S. Lakshmanan ◽  
Bryan A. Chin
Keyword(s):  
Salmonella Typhimurium ◽  
Polyclonal Antibody ◽  
Sensor Platform ◽  
Different Temperatures ◽  
Magnetostrictive Sensor
Sign in / Sign up

Export Citation Format

Share Document