Inhibitory effects of 5-azaorotate in Escherichia coli

1965 ◽  
Vol 30 (10) ◽  
pp. 3513-3519 ◽  
Author(s):  
A. Čihák ◽  
F. Šorm
Keyword(s):  
Escherichia Coli ◽  
Inhibitory Effects

Screening of Commercial and Pecan Shell–Extracted Liquid Smoke Agents as Natural Antimicrobials against Foodborne Pathogens

2012 ◽  
Vol 75 (6) ◽  
pp. 1148-1152 ◽  
Author(s):  
ELLEN J. VAN LOO ◽  
D. BABU ◽  
PHILIP G. CRANDALL ◽  
STEVEN C. RICKE
Keyword(s):  
Escherichia Coli ◽  
Foodborne Pathogens ◽  
Salmonella Enteritidis ◽  
Antioxidant Properties ◽  
Inhibitory Effects ◽  
Natural Antimicrobials ◽  
E Coli ◽  
Liquid Smoke ◽  
Water Based ◽  
Smoke Sample

Liquid smoke extracts have traditionally been used as flavoring agents, are known to possess antioxidant properties, and serve as natural alternatives to conventional antimicrobials. The antimicrobial efficacies of commercial liquid smoke samples may vary depending on their source and composition and the methods used to extract and concentrate the smoke. We investigated the MICs of eight commercial liquid smoke samples against Salmonella Enteritidis, Staphylococcus aureus, and Escherichia coli. The commercial liquid smoke samples purchased were supplied by the manufacturer as water-based or concentrated extracts of smoke from different wood sources. The MICs of the commercial smokes to inhibit the growth of foodborne pathogens ranged from 0.5 to 6.0% for E. coli, 0.5 to 8.0% for Salmonella, and 0.38 to 6% for S. aureus. The MIC for each liquid smoke sample was similar in its effect on both E. coli and Salmonella. Solvent-extracted antimicrobials prepared using pecan shells displayed significant differences between their inhibitory concentrations depending on the type of solvent used for extraction. The results indicated that the liquid smoke samples tested in this study could serve as effective natural antimicrobials and that their inhibitory effects depended more on the solvents used for extraction than the wood source.

Synthesis Of Copper Nanometal Coupled With Vitamin-E And Investigating Its Potential To Control Oxidative Cell Damage And Microbial Spoilage In Seafood

2021 ◽  
Vol 23 (08) ◽  
pp. 678-693
Author(s):  
Haris. V.T ◽  
◽  
Manohar. M ◽  
Kuppannan Gobianand ◽  
◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Vitamin E ◽  
Mtt Assay ◽  
Cell Damage ◽  
Green Emission ◽  
Plate Count ◽  
Diffusion Method ◽  
Inhibitory Effects ◽  
Microbial Spoilage ◽  
Spoilage Bacteria

The metabolism of spoilage organism in the seafood is a major cause of fish spoilage. Lipid oxidation leads to production of intermediate peroxides causing bad odor and offflavour producing compounds. Hence, based on the hurdle technology method and applications of nanotechnology, the inhibitory effects of copper oxide nanoparticles coupled with vitamin-E (CuONPs+VE) was investigated with the aim of controlling the oxidative cell damage in seafood by estimating Reacting Oxygen Species (ROS) using 2’,7’- dichlorodihydrofluorescein diacetate (DCF) and preventing microbial spoilage by studying the cell viability using MTT assay in the present study. The MTT assay reveals that the CuONPs+VE inhibited the metabolic activity of spoilage bacteria which was confirmed from the inhibition percentage values against the test organisms. The CuONPs+VE exposed Escherichia coli reduced upto 86 ± 0.57% after enumerating the CFU in a Plate Count Agar media. Salmonella sp and Shigella sp exhibited 89 ± 1.04% and 85 ± 0.25% respectively. The qualitative inhibitory effect of Nanometal vitamin complex against three test bacteria, were evaluated by agar diffusion method. Among the four different concentrations of Nanometal vitamin complex, the higher concentration (4X – 40μg/ml) exhibited maximum inhibitory effects in terms of zone of clearance. Against Escherichia coli, 12.3 ± 1.25mm of inhibitory zones were found evident. Salmonella sp showed 15.6 ± 0.57mm of inhibitory zones and Shigella sp revealed the inhibition zone of about 16.6 ± 1.04mm. The anti-oxidative defence mechanisms operating in the cells for scavenging of ROS was performed using DCF. The cells which are pre-incubated with CuONPs+VE and then exposed to H2O2 show insignificant green emission indicating a clear advantage of the nanoparticle form of vitamin-E (CuONPs+VE) in preventing oxidative cell death.

scholarly journals Inhibitory effects of Lepidium sativum polysaccharide extracts on TNF-α production in Escherichia coli-stimulated mouse

3 Biotech ◽  
2018 ◽  
Vol 8 (6) ◽  
Author(s):  
Ajaz Ahmad ◽  
Basit Latief Jan ◽  
Mohammad Raish ◽  
Khalid M. Alkharfy ◽  
Abdul Ahad ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Lepidium Sativum ◽  
Inhibitory Effects ◽  
Tnf Α

scholarly journals Effects of Essential Oils on Escherichia coli Inactivation in Cheese as Described by Meta-Regression Modelling

Foods ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 716
Author(s):  
Beatriz Nunes Silva ◽  
Vasco Cadavez ◽  
José António Teixeira ◽  
Ursula Gonzales-Barron
Keyword(s):  
Escherichia Coli ◽  
Essential Oils ◽  
Meta Analysis ◽  
Inhibitory Effects ◽  
Food Preservatives ◽  
E Coli ◽  
Log Reduction ◽  
Bactericidal Properties ◽  
Study Characteristics ◽  
Meta Regression

The growing intention to replace chemical food preservatives with plant-based antimicrobials that pose lower risks to human health has produced numerous studies describing the bactericidal properties of biopreservatives such as essential oils (EOs) in a variety of products, including cheese. This study aimed to perform a meta-analysis of literature data that could summarize the inactivation of Escherichia coli in cheese achieved by added EOs; and compare its inhibitory effectiveness by application method, antimicrobial concentration, and specific antimicrobials. After a systematic review, 362 observations on log reduction data and study characteristics were extracted from 16 studies. The meta-regression model suggested that pathogenic E. coli is more resistant to EO action than the non-pathogenic type (p < 0.0001), although in both cases the higher the EO dose, the greater the mean log reduction achieved (p < 0.0001). It also showed that, among the factual application methods, EOs’ incorporation in films render a steadier inactivation (p < 0.0001) than when directly applied to milk or smeared on cheese surface. Lemon balm, sage, shallot, and anise EOs showed the best inhibitory outcomes against the pathogen. The model also revealed the inadequacy of inoculating antimicrobials in cheese purposely grated for performing challenge studies, as this non-realistic application overestimates (p < 0.0001) the inhibitory effects of EOs.

scholarly journals Composition and Antibacterial Activity of Essential Oils from Leaf, Stem and Root of Chrysanthemum parthenium (L.) Bernh. from Iran

2009 ◽  
Vol 4 (6) ◽  
pp. 1934578X0900400 ◽  
Author(s):  
Ali Shafaghat ◽  
Hajar Sadeghi ◽  
Khodamali Oji
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Essential Oils ◽  
Salmonella Typhi ◽  
Inhibitory Effects ◽  
Germacrene D ◽  
Leaf Oil ◽  
Main Components ◽  
Microdilution Broth

The water distilled essential oils from leaves, stems and roots of Chrysanthemum parthenium (L.) Bernh. were analyzed by GC and GC/MS methods. The leaf oil was characterized by a high amount of camphor (56.4%), whereas in the stem oil, camphor (26.0%), trans-β-ocimene (23.6%) and germacrene-d (15.0%) were the major constituents. The main components of the root oil were α-pinene (50.0%), trans-β-farnesene (13.8%) and bicyclogermacrene (11.0%). Antibacterial activity of the leaf, stem and root oil were evaluated using the microdilution broth method. The oils showed inhibitory effects on Escherichia coli and Salmonella typhi, but were not active against Staphylococcus aureus.

scholarly journals DIFFERENTIAL INHIBITORY EFFECTS OF CHOLERA TOXOIDS AND GANGLIOSIDE ON THE ENTEROTOXINS OF VIBRIO CHOLERAE AND ESCHERICHIA COLI

1973 ◽  
Vol 137 (4) ◽  
pp. 1009-1023 ◽  
Author(s):  
Nathaniel F. Pierce
Keyword(s):  
Escherichia Coli ◽  
Binding Sites ◽  
Competitive Inhibitor ◽  
Inhibitory Effect ◽  
Inhibitory Effects ◽  
E Coli ◽  
Stable Component ◽  
Heat Stable ◽  
Cholera Enterotoxin ◽  
Gut Mucosa

Natural cholera toxoid appears to act as a competitive inhibitor of cholera enterotoxin and is thus a useful tool for studying the interaction of cholera enterotoxin with cell membranes. Cholera enterotoxin binds to gut mucosa more rapidly than does its natural toxoid. Once binding occurs, however, it appears to be prolonged for both materials. Formalinized cholera toxoid has no inhibitory effect upon cholera enterotoxin. Enterotoxic activity, ability to bind to gut mucosa, and antitoxigenicity appear to be independent properties of cholera enterotoxin. Natural cholera toxoid does not inhibit Escherichia coli enterotoxin, indicating that although the two enterotoxins activate the same mucosal secretory mechanism they occupy different binding sites in the mucosa. Ganglioside, which may be the mucosal receptor of cholera enterotoxin, is highly efficient in deactivating cholera enterotoxin. By contrast, ganglioside is relatively inefficient in deactivating heat-labile E. coli enterotoxin and is without effect upon the heat-stable component of E. coli enterotoxin. These findings suggest that ganglioside is not likely to be the mucosal receptor for E. coli enterotoxin. Differences in cellular binding of E. coli and cholera enterotoxins may explain, at least in part, the marked differences in the time of onset and duration of their effects upon gut secretion.

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