Inhibition Of Clostridium Botulinum Research Articles

Detection and inhibition of Clostridium botulinum in some Egyptian fish products by probiotics cell-free supernatants as bio-preservation agents

The detection and inhibition of Clostridium botulinum by probiotics' cell-free supernatants, as a bio-preservation strategy, were investigated in some Egyptian fish-stuffs i.e., canned sardines, fesikh, moloha, renga, and anchovy. The conventional and multiplex polymerase chain reaction were used to detect C. botulinum, while the inhibitory and antioxidant capacity of four probiotics' cell-free supernatants were assessed using disc diffusion assay (DDA) and radical scavenging activity approaches, respectively. The results revealed that the C. botulinum was isolated from 41.6% of the examined products, where the type E. was the most predominant genotyping. The DDA showed that Lactobacillus bulgaricus EMCC 1102 and L. paracasei EMCC 1103 expressed the highest inhibitory action against C. botulinum type E. Meanwhile, L. bulgaricus EMCC 1102 has higher in vitro antioxidant activity (IC50) than L. paracasei EMCC 1103, mostly due to its high bioactive constituent. Consequently, L. bulgaricus EMCC 1102 was used to control the growth of C. botulinum type E in stored anchovy fillets. L. bulgaricus EMCC 1102 supernatant showed a dose-dependent inhibitory effect on C. botulinum type E. These data provided an innovative perspective on the inhibitory potential of probiotics, as a bio-preservation strategy, to guarantee fish products safety for further applications in the food industry.

Inhibition of Clostridium botulinum in Model Reduced-Sodium Pasteurized Prepared Cheese Products

The 1986 Food Research Institute-Tanaka et al. model predicts the safety of shelf-stable process cheese spread formulations using the parameters of moisture, pH, NaCl, and disodium phosphate (DSP) to inhibit toxin production by Clostridium botulinum. Although this model is very reliable for predicting safety for standard-of-identity spreads, the effects of additional factors have not been considered. The objective of this study was to create a predictive model to include the interactive effect of moisture, pH, fat, sorbic acid, and potassium-based replacements for NaCl and DSP to reflect modern reduced-sodium recipes. Eighty formulations were identified using a central composite design targeting seven factors: 50 to 60% moisture, pH 5.4 to 6.2, 0 to 0.2% sorbic acid, 10 to 30% fat, 1.7 to 2.4% NaCl, 0.8 to 1.6% DSP, and 0 to 50% potassium replacement for sodium salts. Samples were inoculated with proteolytic C. botulinum spores at 3 log spores per g, hot filled into sterile vials, and stored anaerobically at 27°C. Samples were assayed at 0, 1, 2, 3, 4, 8.5, 17.5, 26, and 40 weeks for the presence of botulinum toxin using the mouse bioassay. A parametric survival model was fit to the censored time-to-toxin data. All linear, quadratic, and pairwise effects were considered for model fit. As hypothesized, the effects of pH, sorbate, moisture, DSP, and NaCl were highly significant (P < 0.001). Fat concentration and potassium replacement effects were significant at P < 0.021 and P < 0.057, respectively. The model consistently predicted the safety failure of the toxic samples, but it also predicted failure for some samples that were not toxic. This model is an adjunct to existing models by adding the factors of potassium salts, fat, and sorbic acid to predict the botulinal safety of prepared process cheese products but is not intended to be a substitute for formulation evaluation by a competent process authority.

Effect of Sodium Nitrite and Origanum Oil on Growth and Toxin Production of Clostridium botulinum in TYG Broth and Ground Pork

Inhibition of Clostridium botulinum (strains A, B, and E) growth and toxin production by various concentrations of origanum oil and sodium nitrite was studied for both TYG broth and a model meat system. At concentrations of 100 and 200 ppm, origanum oil was effective in inhibiting C. botulinum growth in TYG broth. In addition, origanum oil acted synergistically with sodium nitrite in inhibiting C. botulinum growth in TYG broth. The inhibitory effect of origanum oil in the meat system was dramatically reduced and had a significant (p≤ 0.05) effect only when used at 400 ppm in combination with 50–100 ppm sodium nitrite.

Inhibition of Clostridium botulinum in Comminuted Bacon by Short-Chain Alkynoic and Alkenoic Acids and Esters

Several short-chain alkynoic and aikenoic acids and esters were screened for inhibition of gas production by Clostridium botulinum in cans of comminuted, nitrite-free, temperature-abused bacon. The most active compounds were propiolic (2-propynoic) acid, methyl and ethyl propiolate, 2-propenoic acid, methyl and ethyl propenoate, and mono- and dimethyl and ethyl fumarate. Maleic acid, methylmaleic acid, ethyl maleate, 2-methyl propenoic acid, trans-2-methyl crotonic acid, 3-methyl-2-butenoic acid, 3-methylallyl alcohol, vinyl crotonate, methylmalonic acid, dimethyl glutarate, 2,4-hexadien-1-ol, cis-3-hexenoic acid, 4-pentenoic acid, trans-2-pentenoic acid and ethylidene acetic acid were less active. A more comprehensive study on the inhibition of toxin formation by C. botulinum in comminuted nitrite-free bacon was done by comparing equimolar quantities of some of these compounds with NaNO2 at 120 μg/g and sorbic acid at 9 and 18mM (0.10 and 0.20%). These studies showed that propiolic acid was more effective than either nitrite or sorbic acid. Compounds in this study less active than nitrite or sorbic acid were 3-methylallyl alcohol, 2,4-hexadien-1-ol, dimethyl glutarate and methylmaleic acid.

Influence of pH and Phosphate Buffer on Inhibition of Clostridium botulinum by Antioxidants and Related Phenolic Compounds

The compounds butylated hydroxyanisole (BHA); butylated hydroxytoluene (BHT); tert-butylhydroquinone (TBHQ); nor-dihydroguaiaretic acid (NDGA); 2′, 4′, 5′-trihydroxybutyrophenone (THBP); 8-hydroxyquinoline; isoamyl and isobutyl esters of gallic acid; ethyl, propyl, and butyl esters of p-hydroxybenzoic acid; thymol; 2-isopropylphenol; 2-tert-butylphenol; and 2-tert-butyl-4-methylphenol were tested for their antibotulinal activity in prereduced Thiotone-yeast extract-glucose (TYG) broth with and without hosphate buffer (0.05 M, pH 6.0 and 7.0). Isoamyl gallate, isobutyl gallate, propyl ester of p-hydroxybenzoic acid, NDGA, BHA, 8-hydroxyguinoline, and 2-tert-butylphenol were more inhibitory when phosphate buffer (pH 7.0(was added to prereduced TYG. The propyl and butyl esters of p-hydroxybenzoic acid and 2-isopropylphenol were more effective at pH 6.0 than at pH 7.0, whereas thymol and 8-hydroxyquinoline were slightly more active at pH 7.0 than at pH 6.0 NDGA at 50 μg/ml was the most effective compound tested for delaying growth and toxin production.

Inhibition of Clostridium botulinum by antioxidants, phenols, and related compounds

A total of 75 compounds, including antioxidants, preservatives, gallic acid and p-hydroxybenzoic acid esters, hydroquinones, hydroxyquinolines, phenol derivatives, and related compounds, were screened for their antibotulinal activity in prereduced Thiotone-yeast extract-glucose broth. The most effective inhibitors of Clostridium botulinum growth and toxin production were long-chain esters of p-hydroxybenzoic acid and gallic acid, antioxidants, and butylphenol derivatives. The antioxidant nordihydroguaiaretic acid at 100 microgram/ml delayed the growth and toxin production for the entire incubation period (7 days). Other antioxidants, such as butylated hydroxytoluene, butylated hydroxyanisole, and tert-butylhydroquinone were also very effective (at 200 to 400 microgram/ml) for the inhibition of C. botulinum growth and toxin production. Toxin was detected, although no detectable growth was found by daily absorbance measurements, in the prereduced medium containing 50 to 400 microgram of 8-hydroxyquinoline, pentylphenol, tert-pentylphenol, 3,5-ditert-butylphenol, 3,5-ditert-butylcatechol, (2-hydroxydiphenyl)methane, or (4-hydroxydiphenyl)methane per ml.

SEPARATION OF WATER‐SOLUBLE REACTION PRODUCTS OF NITRITE IN CURED MEAT

ABSTRACTA water‐soluble extract was prepared from a cured meat product which had been manufactured with 15N‐labelled nitrite. Fractionation of this extract on Sephadex G‐10 showed one large and one small peak of 15N content, neither of which contained free nitrite. The two 15N containing peaks did not coincide with the ninhydrin positive or ultraviolet absorbing fractions that were eluted. Examination of the labelled fractions for sulfhydryl groups also proved negative and inhibition of Clostridium botulinum was not accomplished by either of the fractions.

Inhibition of Clostridium botulinum by Strains of Clostridium perfringens Isolated from Soil

Thirty-one soil samples were examined for the presence of organisms capable of inhibiting growth and toxin production of strains of Clostridium botulinum type A. Such organisms were found in eight samples of soil. Inhibiting strains of C. perfringens were found in five samples, of C. sporogenes in three and of Bacillus cereus in three. Three of the C. perfringens strains produced an inhibitor effective on all 11 strains of C. botulinum type A against which they were tested, seven of eight proteolytic type B strains, one nonproteolytic type B strain, five of nine type E strains and all seven type F strains, whether proteolytic or nonproteolytic. They did not inhibit any of 26 type C strains, 6 type D strains, 4 type E strains, or 24 C. sporogenes strains. In mixed culture, an inhibitor strain of C. perfringens repressed growth and toxin production by a C. botulinum type A strain even though it was outnumbered by the latter about 40 times. It also repressed growth and toxin production of C. botulinum in mixed culture of soils in which this latter organism naturally occurred when cooked meat medium but not when trypticase medium was used.

Effect of Added Iron on the Formation of Clostridial Inhibitors

Inhibition of Clostridium botulinum by nitrite was potentiated by the addition of Fe(II) or Fe(III) to the culture medium. The effect of iron was more pronounced when nitrite was added after autoclaving.

Inhibition of Clostridium Botulinum by Sodium Nitrite as Affected by Bacteriological Media and Meat Suspensions

The inhibitory effect of sodium nitrite on the outgrowth of spores of Clostridium botulinum 13983B was studied in various bacteriological media and meat suspensions. The media and meat suspensions were adjusted to pH 6.2 and heated in the presence of nitrite at 110°C for 20min. Perigo factor was produced in Perigo-type medium (PT) and Reinforced Clostridial Medium (RCM) when heated with 20ppm of nitrite, but not in Liver Veal Medium (LVM) and Wynne Fluid Medium (WFM) even when heated with 100ppm of nitrite. Suspensions of 50% meat in water, prepared from under-process, normal-process and over-process meats, required 500ppm, 150ppm and 50ppm of nitrite, respectively, for inhibition of outgrowth.Dialysis removed the inhibitory activity from two of the bacteriological media (LVM and WFM) and from all meat suspensions, but not from PT and RCM media. The residual nitrite concentrations were approximately the same in all seven heated preparation (100ppm added before heating), but the redox potential varied considerably among them. The addition of reducing agents to meat suspensions decreased the redox potential and increased the inhibitory activity but did not induce the formation of the Ferigo factor.

Inhibition of Clostridium Botulinum by Sodium Nitrite in a Bacteriological Medium and in Meat

The inhibitory effect of sodium nitrite on the growth of Clostridium botulinum was studied in a bacteriological medium and in meat suspension. We found that a bacteriological medium heated at 110°C for 20 min with as little as 20ppm of sodium nitrite became inhibitory to C. botulinum and the inhibitor was non-dialyzable. Meat suspension heated with 150ppm of nitrite was inhibitory to C. botulinum, but the inhibitory activity was probably due to a residuum of greater than 100ppm of nitrite: dialysis removed the inhibitory activity. Inhibitor formed in medium could be inactivated by non-fat meat solids but not by fat or water soluble meat extracts. It appears that the inhibitor produced in media is of little or no consequence in explaining the role of nitrite in the safety of commercially-produced canned cured meat.

Inhibition of Clostridium botulinum and Molds in Aged, Surface Ripened Cheese12

Inhibition of Clostridium botulinum and Molds in Aged, Surface Ripened Cheese12

Inhibition of Clostridium botulinum and molds in aged, surface ripened cheese.

Inhibition of Clostridium botulinum and molds in aged, surface ripened cheese.