scholarly journals Response to Oxidative Stress by Foodborne Pathogens

2019 ◽  
Vol 16 (1) ◽  
pp. 93-96
Author(s):  
Khalid Salmeen Almaary
Keyword(s):  
Oxidative Stress ◽  
Fatty Acids ◽  
Foodborne Pathogens ◽  
Volatile Fatty Acids ◽  
Light Stress ◽  
High Light ◽  
Nutrient Deprivation ◽  
Inorganic Acid ◽  
E Coli ◽  
Acid Environment

Microorganisms such as Escherichiacoli and salmonella as well other organisms were affected by stress radiation, mechanical nutrient deprivation, high light stress, environmental and osmotic stress. Most of the enteropathogens to cause disease it was important for them to survive in an acid environment as inside the host, these organisms meet in the small intestine of inorganic acid (H+) in the stomach and a combination of inorganic and organic acids (volatile fatty acids). Here I review some pathogens such as E. Coli and salmonella, their mode of activity and survival against oxidative.

scholarly journals An LC-MS profiling method reveals a route for apocarotene glycosylation and shows its induction by high light stress in Arabidopsis

The Analyst ◽  
2019 ◽  
Vol 144 (4) ◽  
pp. 1197-1204 ◽  
Author(s):  
Jianing Mi ◽  
Kun-Peng Jia ◽  
Aparna Balakrishna ◽  
Jian You Wang ◽  
Salim Al-Babili
Keyword(s):  
Oxidative Stress ◽  
Light Stress ◽  
High Light ◽  
High Light Stress

Apocarotenoid glycosylation serves as a valve regulating carotenoid homeostasis in plants and may contribute to their response to photo-oxidative stress.

Evaluation of Batch and Semicontinuous Application of High Hydrostatic Pressure on Foodborne Pathogens in Salsa

2000 ◽  
Vol 63 (12) ◽  
pp. 1713-1718 ◽  
Author(s):  
ERROL V. RAGHUBEER ◽  
C. PATRICK DUNNE ◽  
DANIEL F. FARKAS ◽  
EDMUND Y. TING
Keyword(s):  
Hydrostatic Pressure ◽  
Foodborne Pathogens ◽  
High Hydrostatic Pressure ◽  
Storage Period ◽  
State University ◽  
E Coli ◽  
Acid Environment ◽  
Low Levels ◽  
Listeria Welshimeri ◽  
Oregon State University

The effects of high hydrostatic pressure (HPP; 545 MPa) on strains of Escherichia coli O157:H7, Listeria monocytogenes, enterotoxigenic Staphylococcus aureus, and nonpathogenic microorganisms were studied in tomato-based salsa. Products were evaluated for the survival of the inoculated pathogens following HPP treatment and after storage at 4°C and 21 to 23°C for up to 2 months. Inoculated samples without HPP treatment, stored under the same conditions, were also evaluated to determine the effects of the acid environment of salsa on the survival of inoculated strains. None of the inoculated pathogens were detected in the HPP-treated samples for all treatments throughout the storage period. Inoculated pathogens were detected in the non–HPP-treated samples stored at 4°C after 1 month, with L. monocytogenes showing the highest level of survivors. In the non–HPP-treated samples stored at 21 to 23°C, E. coli and S. aureus were not detected after 1 week, but L. monocytogenes was detected in low levels. Studies with nonpathogenic strains of the pathogens were conducted at Oregon State University using HPP treatments in a semicontinuous production system. The nonpathogenic microorganisms (E. coli, Listeria innocua, Listeria welshimeri, and nonenterotoxigenic S. aureus) were inoculated together into a feeder tank containing 100 liters of salsa. Microbiological results of samples collected before HPP treatment and from the aseptic filler were similar to those obtained for the pathogenic strains. No survivors were detected in any of the HPP-treated samples.

Factors influencing the persistence ofEscherichia coliO157:H7 lineages in feces from cattle fed grain versus grass hay diets

2010 ◽  
Vol 56 (8) ◽  
pp. 667-675 ◽  
Author(s):  
Ross M.S. Lowe ◽  
Krysty Munns ◽  
L. Brent Selinger ◽  
Linda Kremenik ◽  
Danica Baines ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Fatty Acids ◽  
Volatile Fatty Acids ◽  
Hemorrhagic Colitis ◽  
Escherichia Coli O157 ◽  
Negative Bacterium ◽  
Gram Negative ◽  
E Coli ◽  
Factors Influencing ◽  
Uremic Syndrome

Escherichia coli O157:H7 is a pathogenic, gram-negative bacterium that causes diarrhea, hemorrhagic colitis, and can lead to fatal hemolytic uremic syndrome in humans. We examined the persistence of E. coli O157:H7 lineages I and II in feces held at 4, 12, and 25 °C, from animals fed either grain or hay diets. Three strains of each lineage I and II were inoculated into grain-fed or hay-fed feces, and their persistence was monitored over 28 days. No significant differences in E. coli O157:H7 survival between the 2 lineages in both fecal types was found at the examined temperatures. Volatile fatty acids were higher in grain-fed than in hay-fed feces, resulting in consistently lower pH in the grain-fed feces at 4, 12 and 25 °C. Regardless of lineage type, E. coli O157:H7 CFUs were significantly higher in grain-fed than in hay-fed feces at 4 and 25 °C. Escherichia coli O157:H7 survival was highest in grain-fed feces at 25 °C up to 14 days. Our results indicate that the 2 lineages of E. coli O157:H7 do not differ in their persistence; however, it appears that temperature and feces type both affect the survival of the pathogen.

Diverse roles for chloroplast stromal and thylakoid-bound ascorbate peroxidases in plant stress responses

2008 ◽  
Vol 412 (2) ◽  
pp. 275-285 ◽  
Author(s):  
Saijaliisa Kangasjärvi ◽  
Anna Lepistö ◽  
Kati Hännikäinen ◽  
Mirva Piippo ◽  
Eeva-Maria Luomala ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Stress Responses ◽  
Double Mutant ◽  
Light Stress ◽  
Plant Stress ◽  
Optimal Growth ◽  
Sudden Onset ◽  
High Light ◽  
Mature Leaves ◽  
Ascorbate Peroxidases

Photosynthetic light reactions comprise a significant source of hydrogen peroxide (H2O2) in illuminated leaves. APXs (ascorbate peroxidases) reduce H2O2 to water and play an important role in the antioxidant system of plants. In the present study we addressed the significance of chloroplast APXs in stress tolerance and signalling in Arabidopsis thaliana. To this end, T-DNA (transfer DNA) insertion mutants tapx, sapx and tapx sapx, lacking the tAPX (thylakoid-bound APX), sAPX (stromal APX) or both respectively, were characterized. Photo-oxidative stress during germination led to bleaching of chloroplasts in sapx single-mutant and particularly in the tapx sapx double-mutant plants, whereas the greening process of wild-type and tapx plants was only partially impaired. Mature leaves of tapx sapx double mutants were also susceptible to short-term photo-oxidative stress induced by high light or methyl viologen treatments. After a 2-week acclimation period under high light or under low temperature, none of the mutants exhibited enhanced stress symptoms. Immunoblot analysis revealed that high-light-stress-acclimated tapx sapx double mutants compensated for the absence of tAPX and sAPX by increasing the level of 2-cysteine peroxiredoxin. Furthermore, the absence of tAPX and sAPX induced alterations in the transcriptomic profile of tapx sapx double-mutant plants already under quite optimal growth conditions. We conclude that sAPX is particularly important for photoprotection during the early greening process. In mature leaves, tAPX and sAPX are functionally redundant, and crucial upon sudden onset of oxidative stress. Moreover, chloroplast APXs contribute to chloroplast retrograde signalling pathways upon slight fluctuations in the accumulation of H2O2 in chloroplasts.

Effect of feeding organic acids on gastrointestinal digesta measurements at various times postweaning in pigs challenged with enterotoxigenic Escherichia coli

1993 ◽  
Vol 73 (4) ◽  
pp. 931-940 ◽  
Author(s):  
C. R. Risley ◽  
E. T. Kornegay ◽  
M. D. Lindemann ◽  
C. M. Wood ◽  
W. N. Eigel
Keyword(s):  
Escherichia Coli ◽  
Fatty Acids ◽  
Lactic Acid ◽  
Organic Acids ◽  
Volatile Fatty Acids ◽  
Enterotoxigenic Escherichia Coli ◽  
Volatile Acid ◽  
Measurable Effect ◽  
E Coli ◽  
Effect Of Feeding

In Study 1, pigs (n = 54) weaned at 21 ± 2 d were fed a 20% CP corn-soybean meal based diet only (control) or with 1.5% fumaric or 1.5% citric acid. One half of the pigs on each treatment were orally challenged on days 3, 7 or 14 postweaning with 1010E. coli (0157:K88+) to observe the effects on scouring and on intestinal digesta pH, Cl− concentration, VFA and non-volatile acid profiles, and microflora concentrations in the stomach, jejunum, cecum and lower colon when pigs were necropsied 5, 9 or 16 d postweaning. The E. coli challenge increased (P < 0.05) the severity of scouring. Organic acids had no appreciable effects on severity of scouring and intestinal measurements except for fumaric and succinic acid concentrations which were greater in the stomach (P < 0.001) and jejunum (P < 0.05) of pigs fed fumaric acid. The E. coli challenge had no significant effect on pH, Cl− concentration, and lactobacillus or E. coli concentrations, but did increase (P < 0.05) the concentration of lactic acid in the jejunum, and total VFA in the lower colon. From days 5 to 16 postweaning, pH decreased (P < 0.002) in the cecum, Cl− concentration increased (P < 0.03) in the jejunum, lactobacillus counts decreased (P < 0.001) in the jejunum and increased (P < 0.004) in the lower colon, and E. coli counts decreased in the jejunum (P < 0.07), cecum (P < 0.02) and lower colon (P < 0.001). In Study 2, pigs (n = 96) weaned at 21 ± 2 d were similarly fed organic acids as in Study 1 and half of the animals in each treatment were orally challenged with E. coli on day 3 postweaning. During the 15-d experiment, E. coli challenge decreased (P < 0.05) ADG by 20% and increased F:G 19% from 7 to 15 d postweaning and increased (P < 0.001) the severity of scouring between days 4 and 11 postweaning. Feeding organic acids had no measurable effect on growth performance or scouring and did not modify the effects of the postweaning E. coli challenge. Key words: Pigs, pH, organic acids, volatile fatty acids, lactobacillus, Escherichia coli

scholarly journals Volatile fatty acids build-up and its effect on E. coli inactivation during excreta stabilisation in single-stage and two-stage systems

2018 ◽  
Vol 8 (2) ◽  
pp. 257-267 ◽  
Author(s):  
Joy Riungu ◽  
Mariska Ronteltap ◽  
Jules B. van Lier
Keyword(s):  
Fatty Acids ◽  
Decay Rate ◽  
Volatile Fatty Acids ◽  
Flow Reactor ◽  
Plug Flow ◽  
Single Stage ◽  
Pathogen Inactivation ◽  
Two Stage ◽  
E Coli ◽  
Reactor Length

Abstract Digestion and co-digestion of faecal matter collected from urine diverting dehydrating toilet faeces (UDDT-F) and mixed organic market waste (OMW) was studied in single stage pilot scale mesophilic plug-flow anaerobic reactors at UDDT-F:OMW ratios 4:1 and 1:0. Escherichia coli inactivation and volatile fatty acids (VFA) build-up was monitored at sampling points located along the reactor profile. When applying UDDT-F:OMW ratio of 4:1 at 12% total solids (TS), E. coli inactivation achieved was 2.3 log times higher than that achieved in UDDT-F:OMW ratio of 1:0. In subsequent trials, a two-stage reactor was researched, applying a UDDT-F:OMW ratio of 4:1 and 10 or 12% TS slurry concentrations. Highest VFA concentrations of 16.3 ± 1.3 g/L were obtained at a pH of 4.9 in the hydrolysis/acidogenesis reactor, applying a UDDT-F:OMW ratio of 4:1 and 12% TS, corresponding to a non-dissociated (ND)-VFA concentration of 6.9 ± 2.0 g/L. The corresponding decay rate reached a value of 1.6 per day. In the subsequent methanogenic plug-flow reactor, a decay rate of 1.1 per day was attained within the first third part of the reactor length, which declined to 0.6 per day within the last third part of the reactor length. Results show that a two-stage system is an efficient way to enhance pathogen inactivation during anaerobic digestion.

Sign in / Sign up

Export Citation Format

Share Document