Antibacterial Effect of Volatile Fatty Acids in Enteric E. coli-infections of Rabbits

2010 ◽  
Vol 27 (8) ◽  
pp. 631-639 ◽  
Author(s):  
L. Prohászka
Keyword(s):  
Fatty Acids ◽  
Volatile Fatty Acids ◽  
Antibacterial Effect ◽  
E Coli

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.

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.

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.

scholarly journals In Vitro Evaluation of the Effects of Tylosin on the Composition and Metabolism of Canine Fecal Microbiota

Animals ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 98
Author(s):  
Carlo Pinna ◽  
Carla Giuditta Vecchiato ◽  
Monica Grandi ◽  
Ludovica Maria Eugenia Mammi ◽  
Claudio Stefanelli ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Volatile Fatty Acids ◽  
Control Diet ◽  
Fecal Microbiota ◽  
Total Volatile ◽  
E Coli ◽  
Ph Values ◽  
Fecal Suspension ◽  
Set Up

The present study investigated the in vitro effects of tylosin (TYL), alone or associated with prebiotics (PRE), on selected canine fecal parameters. Eight treatments were set up: control diet with no addition of substrates; TYL; Fructooligosaccharides (FOS); Galactooligosaccharides (GOS); Xylooligosaccharides (XOS); TYL + FOS; TYL + GOS; TYL + XOS. The flasks (five for treatment), containing a canine fecal suspension (prepared with the feces of healthy adult dogs) and the residue of an in vitro digested dry dog food, were incubated in an anaerobic chamber at 39 °C. TYL and PRE were added at a concentration of 0.2 and 1 g/L, respectively. Samples were collected after 6 and 24 h for analyses. PRE decreased pH values, iso-butyrate, and iso-valerate throughout the incubation; increased lactobacilli, cadaverine, and, tendentiously, total volatile fatty acids after 6 h; increased n-butyrate, putrescine, spermidine, and reduced spermine and E. coli after 24 h. TYL resulted in lower total volatile fatty acids and lactobacilli and higher Clostridium cluster I after 6 h and higher pH values, spermidine, and E. coli throughout the study. When associated with TYL, PRE counteracted some undesirable effects of the antibiotic such as the decrease of lactobacilli and Clostridium cluster XIVa at both 6 and 24 h. In the present study, TYL exhibited inhibitory effects on canine fecal microbiota partially counteracted by PRE supplementation.

Purple Prairie Clover (Dalea purpurea Vent) Reduces Fecal Shedding of Escherichia coli in Pastured Cattle

2015 ◽  
Vol 78 (8) ◽  
pp. 1434-1441 ◽  
Author(s):  
L. JIN ◽  
Y. WANG ◽  
A. D. IWAASA ◽  
Y. LI ◽  
Z. XU ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Fatty Acids ◽  
Volatile Fatty Acids ◽  
Ct Scanning ◽  
Cattle Grazing ◽  
Scanning Electron Micrographs ◽  
Fecal Shedding ◽  
E Coli ◽  
Branched Chain ◽  
Filamentous Material

A 3-year (2009 to 2011) grazing study was conducted to assess the effects of purple prairie clover (PPC; Dalea purpurea Vent) on fecal shedding of total Escherichia coli in cattle. Three pasture types were used in the experiment: bromegrass (Check), mixed cool season grasses with PPC (Simple), and mixed cool and warm grasses with PPC (Complex). Pastures were rotationally grazed during a summer and fall grazing period. PPC was grazed in summer at the vegetative or early flower stage and at the flower or early seed stage during the fall. Fecal samples were collected for enumeration of E. coli and chemical analyses. Forage samples were collected throughout grazing for analysis. Condensed tannins (CT) were only detected in Simple and Complex pastures that contained PPC, with higher concentrations found in the fall than in the summer. Fecal counts of E. coli in cattle grazing Simple and Complex pastures linearly decreased (P &lt; 0.05) over summer to fall in all 3 years, an outcome not observed in cattle grazing the Check pasture. Across the three grazing seasons, fecal E. coli was lower (P &lt; 0.05) in cattle grazing Simple and Complex pastures than in those grazing the Check pasture during the fall. During the fall, feces collected from cattle grazing the Check pasture had higher (P &lt; 0.05) values for pH, N, NH3-N, total volatile fatty acids, and branched-chain volatile fatty acids, but a lower (P &lt; 0.05) acetate:propionate ratio than feces collected from cattle grazing Simple or Complex pastures. In a second experiment, two strains of E. coli were cultured in M9 medium containing 25 to 200 μg/ml of PPC CT. Growth of E. coli was linearly (P &lt; 0.01) reduced by increasing levels of PPC CT. Scanning electron micrographs showed electron-dense filamentous material associated with the outer membrane of E. coli cells exposed to CT. Incorporation of PPC into forage reduced the fecal shedding of E. coli from grazing cattle, likely due to the anti–E. coli properties of PPC CT.

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