Spores Of Clostridium Botulinum Type Research Articles

Prevalence of multi-drug resistant bacteria associated with foods and drinks in Nigeria (2015-2020): A systematic review.

Foods are essential vehicles in human exposure to antibiotic resistant bacteria which serve as reservoirs for resistance genes and a rising food safety concern. Antimicrobial resistance, including multidrug resistance (MDR), is an increasing problem globally and poses a serious concern to human health. This study was designed to synthesize data regarding the prevalence of MDR bacteria associated with foods and drinks sold within Nigeria in order to contribute to the existing findings in this area. A comprehensive literature search on the prevalence of multi-drug resistant bacteria associated with foods and drinks in Nigeria from 2015 to 2020 was conducted using three databases; PubMed, Science Direct and Scopus. After screening and selection, 26 out of 82 articles were used for the qualitative data synthesis. Of the total of one thousand three hundred and twenty-six MDR bacteria reportedly isolated in all twenty-six articles, the highest prevalence (660) was observed in drinks, including water, while the lowest (20) was observed in the article which combined results for both protein and vegetable-based foods. Escherichia sp. had the most frequency of occurrence, appearing as MDR bacteria in ten out of the twenty-six articles. Salmonella sp. appeared as MDR in seven out of the twenty-six articles included in this study, in all seven articles where it was reported, it had the highest percentage (85.4%) prevalence as MDR bacteria. Public health personnel need to ensure critical control during the production and handling of foods and drinks, as well as create more awareness on proper hygienic practices to combat the spread of MDR bacteria becoming a growing food safety issue (Zurfluh et al., 2019; Mesbah et al., 2017; Campos et al., 2019). Foods can be contaminated by different means, including exposure to irrigation water, manure, feces or soil with pathogenic bacteria. Foods can also become contaminated as they are harvested, handled after harvest or during processing if food safety standards are not correctly applied (Meshbah et al., 2017). Food-borne diseases caused by resistant organisms are one of the most important public health problems as they contribute to the risk of development of antibiotic resistance in the food production chain (Hehempour-Baltork et al., 2019). Apart from pathogenic bacteria causing foodborne diseases, foods that are raw or not processed following standard procedures can introduce several antibiotic-resistant bacteria (ARB) to consumers (Gekemidis et al., 2018). Antibiotic resistance, though harbored in non-pathogenic bacteria, can potentially be spread through horizontal gene transfer to other species including opportunistic pathogens that are present in the environment or after consumption of ARB-contaminated foods. When ARB-contaminated foods are consumed, the spread of antibiotic resistant genes may affect the gut microbiome thereby contributing to the pool of antibiotic-resistance genes (ARG) in the human gut (Gekemidis et al, 2018). MDR bacteria have been defined as bacteria that are resistant to at least one antimicrobial agent present in three or more antimicrobial classes (Sweeny et al., 2018). There has been an increase in drug resistance in pathogens isolated from food for human consumption with species of Escherichia coli and Salmonella enterica being considered among the most important pathogens due to their ability to effect zoonotic transfer of resistant genes (Canton et al., 2018; Maneilla-Becerra et al., 2019). However, other pathogens, such as Vibrio spp., some species of Aeromonas, spores of Clostridium botulinum type F, and Campylobacter, have been linked to food-borne diseases in humans who have consumed seafood or other animal foods (Maneilla-Becerra et al., 2019). Some other resistant bacteria associated with foods include Staphylococcus aureus, Listeria spp., and Shigella spp. (Maneilla-Becerra et al., 2019)This study was therefore designed to synthesize data (2015-2020) regarding the prevalence of MDR bacteria associated with foods and drinks sold within Nigeria in order to contribute to the existing findings in this area.

Mathematical modeling and Monte Carlo simulation of thermal inactivation of non-proteolytic Clostridium botulinum spores during continuous microwave-assisted pasteurization

The objective of this study was to develop a mathematical method to predict the internal temperature history of products exposed to a microwave-assisted pasteurization system and use Monte Carlo simulation to analyze the inactivation of the spores of Clostridium botulinum Types B in beef meatball trays and Type E in salmon fillet trays. With a target of 6 log-reduction in the spores, the simulation showed >98.8% and 99.1% of the processes will achieve a minimum of 5-log reductions of C. botulinum Type B in beef meatball trays and Type E in salmon fillet trays, respectively. Sensitivity analysis showed that the heating temperature, time, and product heating rate in the Microwave-Assisted Heating section and the heating temperature in the Pre-Heating section are four most critical factors affecting the accumulation of lethality. The results of this study may be used to guide the development of more effective thermal processes in microwave-assisted pasteurization systems.

Influence of Temperature and pH on Growth and Toxin Production from Spores of Clostridium botulinum

ABSTRACT This study was undertaken to determine the influence of temperature and pH on growth and time to toxicity of spores of Clostridium botulinum types isolated from tropical fish. Anaerobic meat medium with varying temperatures (4–30°C) and pH values (4.5 to 7.0) were used and toxicity was tested by mouse bioassay. An increase in lag phase was noticed by lowering the growth temperature from 30°C to 4°C and the pH from 7.0 to 4.6. The probability of toxin production increased with storage time, but decreased as either the pH or storage temperature and pH (combined stress) was decreased. The results indicated the effect of pH in controlling toxin production by C. botulinum spores in refrigerated foods with pH 5.0 or < 5.0.

Inactivation of Clostridium botulinum Type A Spores by High-Pressure Processing at Elevated Temperatures

The effects of high-pressure treatments at various temperature-time combinations on the inactivation of spores of Clostridium botulinum type A strains 62-A and BS-A in phosphate buffer (0.067 M, pH 7.0) and in a crabmeat blend were investigated. The log unit reduction of strain 62-A spores increased significantly as the processing pressure increased from 417 to 827 MPa (from 60,000 to 120,000 lb/in2) at 75°C. The reduction of BS-A and 62-A spores in either medium increased as processing temperatures increased from 60 to 75°C and processing times increased from 5 to 15 or 20 min at a maximum pressure of 827 MPa. Approximately 2- and 3-log reductions of BS-A and 62-A spores, respectively, in phosphate buffer were obtained at the maximum pressure–maximum temperature combination of 827 MPa and 75°C for a processing time of 20 min. Processing for 15 min at the maximum pressure–maximum temperature combination resulted in maximum reductions of 3.2 and 2.7 log units for BS-A and 62-A spores, respectively, in the crabmeat blend. Results obtained in this study indicate that the crabmeat blend did not protect BS-A and 62-A spores against inactivation by high-pressure processing.

An outbreak in Italy of botulism associated with a dessert made with mascarpone cream cheese.

In the late 1996, an outbreak of botulism affected eight young people (age of patients ranged from 6 to 23 years) in Italy. The onset of the illness was the same for all of these patients: gastrointestinal symptoms (nausea and vomiting) followed by neurologic symptoms. The most common neurologic symptoms were dysphagia, respiratory failure (100%), diplopia (87%), dysarthria, ptosis (75%) and mydriasis (50%). All patients required mechanical ventilation. Botulinum toxin was detected from two of respectively five sera and six stool samples analysed, while spores of Clostridium botulinum type A were recovered from all patient' faeces. The epidemiological investigation led to suspect a commercial cream cheese ('mascarpone') as a source of botulinum toxin: indeed, it had been eaten by all the patients before onset of the symptoms, either alone or as the (uncooked) ingredient of a dessert, 'tiramisù'. Botulinum toxin type A was found in the 'tiramisù' leftover consumed by two patients and in some mascarpone cheese samples collected from the same retail stores where the other patients had previously bought their cheeses. A break in the cold-chain at the retail has likely caused germination of C. botulinum spores contaminating the products, with subsequent production of the toxin. One of the patients died, while the others recovered very slowly. Prompt international alerting and recall of the mascarpone cheese prevented the spread of the outbreak due to the wide range of distribution, demonstrating the importance of a rapid surveillance system. None of the people complaining of symptoms after the public alert resulted positive for botulinum spores and toxin.

Arginine Promotes Toxin Formation in Cheddar Cheese by Clostridium botulinum

The production of botulinal toxin by a mixture of spores of Clostridium botulinum types A and B was evaluated in Cheddar cheese supplemented with L-arginine (1% wt/wt) and containing one of three levels of sodium chloride (0, 0.9, or 1.8%). Botulinal toxin was formed in cheeses containing an increased level of L-arginine (1%) and reduced levels of sodium chloride (0 or 0.9%). No toxin was formed in Cheddar with arginine and 1.8% salt or in any of the cheeses not supplemented with arginine. The pH increased from 5.05–5.2 to 5.7–6.0 in the cheeses with increased arginine, but the pH change alone did not permit growth of C. botulinum. Metabolism of arginine may also have promoted the synthesis of compatible metabolites for salt resistance. The results indicate that an important factor supporting growth of C. botulinum in cheese is the availability of L-arginine.

Implication of coprophagy in pathogenesis of chicken botulism.

Oral administration of 1 x 10(7) viable spores of Clostridium botulinum type C killed the chickens kept on a board floor to allow them coprophagy, whereas the same dose of the spores failed to develop symptoms in those kept on a wire-net floor not to allow them coprophagy. Type C toxin was detected in the cecal droppings of the chickens of both the groups after feeding the spores and also in serum of symptomatic as well as asymptomatic chickens kept on a board floor. Thus, coprophagy, by which chickens ingest type C toxin (C1 L toxin) and the bacterial cells, seems to be a prerequisite for development of chicken botulism.

Heat Resistance of Spores of Clostridium botulinum Types A and B in Soy Milk

[in Japanese]

Germination of Spores of Clostridium botulinum Type G

Germination of spores of Clostridium botulinum type G under various conditions of heat activation, incubation temperature and minimum nutrition was studied. The spores were optimally germinated in a mixture of L-cysteine + L-lactacte + bicarbonate. The rate and extent of germination were greatly increased when unheated spores were heat-activated at 75°C for 10 min before exposure to the germination medium. Maximum germination was obtained at incubation temperatures of 37 to 45°C within 1 h. However, germination occurred substantially even at 4°C if the incubation time was extended to 48 h.

Evaluation of Factors Involved in Antibotulinal Properties of Pasteurized Process Cheese Spreads

Pasteurized process cheese spreads with various levels of sodium chloride, disodium phosphate, moisture and pH were challenged with spores of Clostridium botulinum types A and B. Response surface methodology was used to design experiments that would yield maximum results with the minimum number of trials. Supplemental experiments were added to further clarify the response and to examine combinations of special interest. A total of 304 treatment combinations (batches) was incubated at 30°C, and five samples from each batch were taken at predetermined intervals up to 42 wk of incubation and tested for botulinal toxin. Sodium chloride and disodium phosphate inhibited botulinal toxin production with similar effectiveness. The inhibitory effect of low pH (<5.7) and low moisture (<54%) levels on botulinal toxin production was as expected, i.e., as either pH or moisture went up, it was necessary to increase sodium chloride and/or phosphate concentrations to compensate. Differences in water activity between cheese spreads with different compositions were observed but they were too small to use for controlling the properties of the products, e.g., a range of 9% in moisture level (51 to 60%) produced only 0.022 variation in water activity. Combinations of the above factors were developed for safe pasteurized process cheese spreads containing up to 60% moisture.

Inhibition of Clostridium botulinum Type E Toxin Formation by Potassium Chloride and Sodium Chloride in Hot-Process (Smoked) Whitefish (Coregonus clupeaformis)

Whitefish steaks were brined in NaCl, KCl, or equimolar NaCl:KCl to contain similar chloride ion concentration and inoculated intramuscularly with 10 or 100 spores of Clostridium botulinum type E per gram of fish. Steaks were then heated in a simulated (i.e., without smoke) hot-smoke process to internal temperatures of 62.8° to 76.7°C (145°–170°F) for the final 30 min of a 2- to 3-h process, packaged under vacuum in oxygen-impermeable film, and stored at abuse temperature of 25°C. During 7 d of storage, toxin production was inhibited in steaks containing more than 0.66 ionic strength NaCl, 0.64 KCl, or 0.71 equimolar NaCl:KCl. The results indicate that it is feasible to substitute KCl for NaCl in hot-process smoked fish for inhibition of outgrowth and toxin production by Clostridium botulinum type E.

Botulism in metronidazole- treated conventional adult mice challenged orogastrically with spores of Clostridium botulinum type A or B.

Conventional adult mice were pretreated with metronidazole to make their intestinal tracts receptive to colonization by Clostridium botulinum. These mice, in groups of 10, were fed 0 (controls), 10(2), 10(3), 10(4), or 10(5) C. botulinum type B spores and were placed for observation in filter-lid cages whose screen floors minimized the amounts of feces available for coprophagy. The opportunity to eat feces was made equal for all mouse groups by placing one mouse of every group in each of 10 cages. Mice given a spore inoculum began to develop botulism after incubation periods of slightly less than 2.75 days. Morbidity rates, which reached maxima within 5 days of challenge, were related to inocula levels. Mortality rates were also dose related. Mice given 10(5) spores and then type B antitoxin intraperitoneally, a treatment not affecting intraintestinal toxin production, remained healthy. Morbidity among control mice was seldom more than 10% and could be ascribed to toxin ingested with feces. A C. botulinum type A spore suspension gave similar results, although morbidity and mortality rates were generally lower than after challenge with a comparable number of type B spores. Mice challenged with 10(2) or 10(5) spores had similar toxin levels in their large intestines 48 h later. Morbidity rates correlated better with toxin levels in the small intestines.

The effect of oxygen and redox potential on growth of Clostridium botulinum type E from a spore inoculum

Small volumes of oxygen introduced into vials of medium at pH 7 prepared under anaerobic conditions reacted with the medium during sterilization by heating, and also raised the redox potential. The partial pressure of oxygen ( pO 2) in the medium, and the redox potential ( E h ) were measured and their effect on the number of spores of Clostridium botulinum type E required to produce growth, and hence on the probability of growth from single spore inocula, was determined. In the presence of a pO 2 of up to 4·5 × 10 −3 atm resulting in an E h of c. + 217 mV, the probability of growth from single spores within 5 days at 20°C was equal to that in strictly anaerobic conditions at an E h of − 400 mV. At pO 2 values of between 5·3 × 10 −3 atm and 8·4 × 10 −3 atm corresponding to E h values of between + 226 mV and + 254 mV an inoculum of between 10 and 1000 spores was required to produce growth and at pO 2 values of between 1·12 × 10 −2 atm,and 1·6 × 10 −2 atm, corresponding to redox potentials of between + 271 mV and + 294 mV, the number of spores required to produce growth was between 2 × 10 4 and > 2 × 10 5. The relationship between pO 2 and E h depends on the chemical nature of a culture medium or food, and in order to assess the probable influence of these parameters on growth of C. botulinum in a medium or a food it is necessary to determine both the redox potential and the partial pressure of oxygen.

Toxin production by Clostridium botulinum types A and B in unpasteurized cured meat products held at 15 and 27 degrees C.

Unpasteurized cured hams were prepared from pork loins by curing with salt (3 or 6%) and 0.02% sodium nitrite. The hams were inoculated with the spores of Clostridium botulinum types A and B and held for 56 days at 15 or 27°C. No botulinum toxin developed at 15°C in the ham cured with 3% salt and nitrite, but type A toxin lower than 400 mouse ip MLD/g was detected after the 7th day of holding at 27°C. The ham cured with 6% salt and sodium nitrite never became toxic at 15 or 27°C.

Detection of Clostridium Botulinum in Honey by a Procedure Involving Membrane Filtration

A new procedure for the detection of botulinal spores in honey was proposed. This involved dilution of honey samples, heating for spore activation and for accelerated filtration, membrane filtration, incubation of the membranes in a recovery medium, and toxin assays. The numbers of spores of Clostridium botulinum types A and B added and the numbers of spores recovered by this method were essentially the same.

Effect of d1‐α‐Tocopherol on Antibotulinal Effectiveness of Sodium Nitrite in Bacon

ABSTRACTIt has been proposed that d1‐α‐tocopherol be added to bacon to reduce the formation of nitrosamines upon frying. The effect of d1‐α‐tocopherol on antibotulinal properties of bacon formulated with sodium nitrite was tested. The bacon was made with 0 or 0.9% sucrose and 0, 500 or 1,000 ppm d1‐α‐tocopherol. Each slice was inoculated with heat‐shocked spores of Clostridium botulinum types A and B, then incubated at 27, 25 or 23°C in vacuum packages. Gassy samples were assayed for botulinum toxin as they occurred. The addition of d1‐α‐tocopherol up to 1,000 ppm did not retard the antibotulinal properties of 120 ppm sodium nitrite in bacon.

Experimental toxicoinfection in infant mice challenged with spores of Clostridium botulinum type E.

Conventionally raised suckling mice were given 10(7) spores of a strain of Clostridium botulinum type E. Most but not all infant mice aged 8 through 19 days at the time of administration died after developing symptoms typical of botulism. However, none of the infant mice challenged with the spores at dose levels lower than 10(6) spores/mouse developed illness.

Production of Botulinum Toxin in Inoculated Pack Studies of Foil-Wrapped Baked Potatoes

Idaho Russet Burbank potatoes were surface or stab inoculated with 10 to 105 spores of Clostridium botulinum type A strain, overwrapped in aluminum foil, baked at 204 C for 50 min or 96 C for 3 h and then held at 22 or 30 C. The shortest incubations resulting in the first botulinogenic potatoes were inversely related to spore doses and ranged from 3 to 7 days; potatoes inoculated with 10 spores were toxic after 5 to 7 days. Total toxin in individual potatoes incubated 3 to 5 days were 5 × 103 to 5 × 105 mouse mean lethal doses. Toxin was not found at distances greater than 1.6 cm from the spore inoculation site. Results indicate that left-over, foil-wrapped, baked potatoes are a perishable food that must be refrigerated.

Temperature, pH, and Spore Load Effects on the Ability of Nisin to Prevent the Outgrowth of Clostridium botulinum Spores

ABSTRACTThe effectiveness of nisin in preventing the outgrowth of spores of Clostridium botulinum types A, B, and E in TPYG broth was profoundly affected by pH, temperature of heat‐shocking, length of the heat‐shocking period, and spore load. Nisin was considerably more effective at pH 6 than at either pH 7 or pH 8 in limiting the outgrowth of all six tested strains. Heat‐damaged spores were also more sensitive to nisin. Both higher heat‐shocking temperatures in the range 20‐30°C higher than the optimal heat‐shocking temperatures for the particular strain and longer heat‐shocking periods served to lower the levels of nisin required to inhibit spore outgrowth. Nisin was more effective against spore loads of 102spores/ml. than higher spore loads of 103 or 104 spores/ml with all of these variables taken into consideration, the order of sensitivity of the spores of the various strains of C. botulinum was strain 56A &lt; strain 69A &lt; strain 113 B = strain 213 B &lt; strain Beluga E &lt; strain Minnesota E

PRODUCT QUALITY AND ENERGY USE IN HIGH TEMPERATURE SMOKING OF FISH

ABSTRACTA process for heating smoked fish was developed such that the lethality of the heating process is equivalent to a 12 decimal reduction of spores of Clostridium botulinum Type E. This lethality is similar to the specifications in the Food &amp; Drug Administration smoked fish Good Manufacturing Practice regulations. The requirements for a fish smoking oven that would be necessary to carry out the process were also determined. The staged temperature process, which started at 160°F (71.1°C) dry bulb and 140°F (60°C) wet bulb, with wet and dry bulb temperatures increases of 10°F (5.6°C) in 10 min increments until the internal temperature of the fish reached 194°F (90°(Z), minimized undesirable defects in the smoked fish product when compared with other smoking (process) schedules. The energy consumption of the recirculating air oven, for the high temperature staged process (186.482 MJ) was found to be twice that for a constant temperature 71.1°C process (92.337 MJ) with most of the energy used attributed to the generation of steam used for humidification, and heat losses through the un insulated ductwork. A heat balance on an oven with steam humidification and a heating element capacity of 35.5 kW showed that only 45.5 kg of product can be processed effectively using the staged temperature process.