Sensitivity of Campylobacter jejuni to Drying

1982 ◽  
Vol 45 (6) ◽  
pp. 507-510 ◽  
Author(s):  
MICHAEL P. DOYLE ◽  
DEBRA J. ROMAN
Keyword(s):  
Campylobacter Jejuni ◽  
Room Temperature ◽  
Skim Milk ◽  
Initial Population ◽  
Log10 Reduction ◽  
Viable Cells ◽  
Large Numbers ◽  
Thermophilic Campylobacter ◽  
And Storage ◽  
Intermediate Rate

Several factors were shown to influence the rate of inactivation of Campylobacter sp. when dried on a glass surface. These included strain, temperature and humidity, and medium used to suspend the organism. Of the strains evaluated, all of three isolates of Campylobacter jejuni exhibited greater tolerance to drying than did a strain of nalidixic acid resistant, thermophilic Campylobacter. Inconsistent results were obtained when organisms were dried and maintained at 25 C. Viable cells from two of four strains having an initial population of >107 were not recovered after 24 h in an anhydrous environment at 25 C. Under comparable conditions, drying C. jejuni FRI-CF8 in the presence of skim milk at 25 C resulted in a >107 log10 reduction of cells within 1 day in one instance; a 5 log10 decline after 7 days in another; and inactivation at an intermediate rate on a third occasion. Rates of death were greatly reduced when cells were dried and held at 4 C. At this temperature and in the presence of skim milk and an anhydrous environment, a 5 log10 reduction of CF8 occurred after 6 weeks. In all instances, greater survival occurred when organisms were dried in the presence of Brucella broth than in skim milk. When held in environments of different relative humidities (RH), survival was greatest in the presence of 14% or less RH. Results suggest that C. jejuni is generally quite sensitive to drying and storage at room temperature, but, at refrigeration temperature and the appropriate humidity, large numbers may survive drying and remain viable for several weeks.

Survival of Campylobacter jejuni in Fresh and Heated Red Meat

1983 ◽  
Vol 46 (9) ◽  
pp. 771-774 ◽  
Author(s):  
PAUL KOIDIS ◽  
MICHAEL P. DOYLE
Keyword(s):  
Heat Treatment ◽  
Campylobacter Jejuni ◽  
Ground Beef ◽  
Red Meat ◽  
Refrigerated Storage ◽  
Log10 Reduction ◽  
Salmonella Spp ◽  
Lamb Meat ◽  
Large Numbers ◽  
D Values

Studies were done to assess the ability of Campylobacter jejuni to survive in fresh ground beef during refrigerated storage and to identify time-temperature treatments needed to inactivate Campylobacter in ground and cubed red meat. The organism survived well in refrigerated ground beef containing large numbers of indigenous bacteria. Relatively little death (< 1.2-log10 reduction) occurred for 7 of 8 strains during 14 d at 4°C. C. jejuni inoculated into ground beef and cubed lamb meat was quite sensitive to heat treatment. D-values for inactivation of campylobacters in ground beef ranged from 5.9 to 6.3 min at 50°C and from 12 to 21 s at 58°C. D-values were generally greater when campylobacters were heated in lamb meat, ranging from 5.9 to 13.3 min and 12.5 to 15.8 s at 50 and 60°C, respectively. All strains of C. jejuni were more sensitive to heat than salmonellae, hence meat heated to a temperature sufficient to inactivate Salmonella spp. should be free of viable campylobacters.

Reformulation of Mice Fodder with Encapsulated Lactobacillus fermentum E5

2019 ◽  
Vol 2 (2) ◽  
pp. 102-108
Author(s):  
Marcelia Sugata ◽  
Andrew Jounathan ◽  
Tji Jan Tan
Keyword(s):  
Sodium Alginate ◽  
Room Temperature ◽  
Storage Period ◽  
Lactobacillus Fermentum ◽  
Drying Process ◽  
Encapsulated Cells ◽  
Viable Cells ◽  
And Storage ◽  
Probiotic Delivery

Common in vivo probiotic delivery through oral gavage may result in esophagealinjury as well as restraint-associated-distress particularly with repeated application. To overcome the issue, in this study, Lactobacillus fermentum E5 was embedded in sodium alginate-chitosan capsules and incorporated with commercial mice fodder. The survival of probiotic following various procedures and storage was evaluated. More than 90% of viable cells were successfully recovered from fresh microcapsules and 95% of the encapsulated probiotics survived freeze drying process. Furthermore, the encapsulated cells exhibitedsurvivability of more than 85% after 28 days storage period at 4°C and room temperature. Reformulation of mice fodder was done by crushing the commercial pellet, adding encapsulated probiotic, mixing, re-pelleting using 3% (v/v) sodium alginate solution as binder. After storing at room temperature, almost 80% of encapsulated L. fermentum E5 in mice fodder survived.

Growth and Survival of Campylobacter fetus subsp. jejuni as a Function of Temperature and pH

1981 ◽  
Vol 44 (8) ◽  
pp. 596-601 ◽  
Author(s):  
M. P. DOYLE ◽  
D. J. ROMAN
Keyword(s):  
Thermal Inactivation ◽  
Skim Milk ◽  
Temperature Dependent ◽  
Growth And Survival ◽  
Campylobacter Fetus ◽  
Large Numbers ◽  
Fetus Subsp ◽  
The Times ◽  
D Values ◽  
Intermediate Rate

The objective of this study was to determine what effect temperature and pH have on the ability of Campylobacter fetus subsp. jejuni to grow and survive. None of three strains of C. fetus subsp. jejuni could grow at 30 C and below or at 47 C and above. The optimum temperature for growth was in the range of 42 to 45 C. Only one of three strains, FRI-CF8, could grow at pH 4.9 and none could grow at pH 4.7. The optimum pH for growth was in the range of 6.5 to 7.5; however, all strains grew well at pH 5.5 to 8.0. Rate of cell death at pH 3.0 to 4.5 was temperature-dependent. At comparable pH, cells of C. fetus subsp. jejuni died most rapidly at 42 C, less rapidly at 25 C and at the slowest rate at 4 C. For example, at pH 4.5, a 3 log10 decrease of cells occurred within 8 h when incubated at 42 C but took 4 days when incubated at 4 C. At 25 C and pH 4.5, cells were inactivated at an intermediate rate. Rates of thermal inactivation of five strains of C. fetus subsp. jejuni were determined at 48, 50, 53, and 55 C in a skim milk heating menstruum. At 48 C, D-values ranged from 7.2 to 12.8 min while at 55 C they ranged from 0.74 to 1.00 min. The times and temperatures used to pasteurize milk should be sufficient to free milk of even unusually large numbers of viable cells of C. fetus subsp.jejuni

Effect of Growth Media and Extended Incubation on the Appearance of Lactose - Nonfermenting Variants in Lactococci

1990 ◽  
Vol 53 (7) ◽  
pp. 583-587 ◽  
Author(s):  
R. P. SINHA
Keyword(s):  
Cell Survival ◽  
Room Temperature ◽  
Simple Technique ◽  
Skim Milk ◽  
Extended Period ◽  
Growth Media ◽  
Genetic Traits ◽  
Stabilizing Effect ◽  
The Media ◽  
And Storage

Growth and storage were investigated for the development of Lac− (lactose-nonfermenting) variants of Lactococcus lactis subsp. lactis C2, ML3 and L. lactis subsp. cremoris ML1, SC607 under different conditions, in an unbuffered medium (M17−), and in media buffered with inorganic or organic phosphates. Strains were grown overnight (16–18 h) at 32°C and subsequently held at 32 and 22°C. The cell survival was much higher at 22°C than at 32°C after storage for 96 h. Most of the survivors in M17− broth were of the Lac− phenotype. Lac− variants were also observed when the cultures were grown in skim milk at 32°C and then held at that temperature for 96 h. These results showed that the lactose-fermenting ability of lactococcus in general is lost when overnight cultures in M17− broth are kept either at room temperature (22°C) or at 32°C for an extended period. However, the cultures in buffered media under similar conditions showed little or no loss of lactose-fermenting ability, suggesting that phosphate in the media had a stabilizing effect on plasmid-encoded lactose-fermenting gene(s). These observations indicate the possibility of utilizing this method as a simple technique for isolating mutants deficient in plasmid-linked genetic traits in lactococci.

Investigations on the Nature of Hemophilia A

1963 ◽  
Vol 09 (01) ◽  
pp. 030-052 ◽  
Author(s):  
Eberhard Mammen
Keyword(s):  
Factor Viii ◽  
Human Plasma ◽  
Barium Sulfate ◽  
Freeze Drying ◽  
Room Temperature ◽  
Hemophilia A ◽  
Normal Human Plasma ◽  
Normal Human ◽  
And Storage ◽  
Prothrombin Activation

SummaryIn this paper an inhibitor is described that is found in hemophilic plasma and serum different from any till now described inhibitor. The inhibitor only inhibits prothrombin activation in the “intrinsic clotting systems”. This inhibitor is probably not present in normal human plasma or serum. It is destroyed by ether and freeze drying, is labile to acid and storage at room temperature. It is stable upon dialysis and has not been adsorbed on barium sulfate, aluminum hydroxide or kaolin. It precipitates at 50% v/v saturation with alcohol. The nature of this inhibitor seems to be a protein or lipoprotein.Factor VIII was isolated from hemophilic plasma. The amount isolated was the same as from normal plasma and the activity properties were not different. Hemophiliacs have normal amounts of factor VIII.

scholarly journals Changes in Particle Size, Sedimentation, and Protein Microstructure of Ultra-High-Temperature Skim Milk Considering Plasmin Concentration and Storage Temperature

Molecules ◽  
2021 ◽  
Vol 26 (8) ◽  
pp. 2339
Author(s):  
So-Yul Yun ◽  
Jee-Young Imm
Keyword(s):  
Particle Size ◽  
High Temperature ◽  
Storage Temperature ◽  
Whey Proteins ◽  
Skim Milk ◽  
Storage Period ◽  
Sediment Analysis ◽  
Sediment Formation ◽  
And Storage ◽  
Ultra High Temperature

Age gelation is a major quality defect in ultra-high-temperature (UHT) pasteurized milk during extended storage. Changes in plasmin (PL)-induced sedimentation were investigated during storage (23 °C and 37 °C, four weeks) of UHT skim milk treated with PL (2.5, 10, and 15 U/L). The increase in particle size and broadening of the particle size distribution of samples during storage were dependent on the PL concentration, storage period, and storage temperature. Sediment analysis indicated that elevated storage temperature accelerated protein sedimentation. The initial PL concentration was positively correlated with the amount of protein sediment in samples stored at 23 °C for four weeks (r = 0.615; p < 0.01), whereas this correlation was negative in samples stored at 37 °C for the same time (r = −0.358; p < 0.01) due to extensive proteolysis. SDS-PAGE revealed that whey proteins remained soluble over storage at 23 °C for four weeks, but they mostly disappeared from the soluble phase of PL-added samples after two weeks’ storage at 37 °C. Transmission electron micrographs of PL-containing UHT skim milk during storage at different temperatures supported the trend of sediment analysis well. Based on the Fourier transform infrared spectra of UHT skim milk stored at 23 °C for three weeks, PL-induced particle size enlargement was due to protein aggregation and the formation of intermolecular β-sheet structures, which contributed to casein destabilization, leading to sediment formation.

scholarly journals Evaluation of Microbial Culture Techniques for the Isolation of Pythium Insidiosum from Equine Tissues

2002 ◽  
Vol 14 (4) ◽  
pp. 288-294 ◽  
Author(s):  
Amy M. Grooters ◽  
Amy Whittington ◽  
Mae K. Lopez ◽  
Michelle N. Boroughs ◽  
Alma F. Roy
Keyword(s):  
Room Temperature ◽  
Microbial Culture ◽  
Sample Type ◽  
Pythium Insidiosum ◽  
Selective Media ◽  
Culture Techniques ◽  
Media Type ◽  
Antibiotic Solution ◽  
And Storage ◽  
Storage Technique

The purpose of this study was to evaluate the effects of sample handling, storage, and culture techniques on the isolation of Pythium insidiosum from infected equine tissues. Tissue and kunker samples obtained immediately posteuthanasia from a horse with subcutaneous pythiosis were used to assess the effects of sample type (kunkers vs. tissues), media type (selective vs. nonselective), storage technique, and storage time on P. insidiosum isolation rate. Overall, isolation rates were higher from fresh kunkers (94.6%) and stored kunkers (76.4%) than from fresh tissues (8.3%) or stored tissues (4.6%). Isolation of P. insidiosum also occurred more often on antibiotic-containing media than on nonselective media for both fresh and stored samples. For samples that were stored for 1–3 days prior to culture, P. insidiosum isolation rates were highest for the following techniques: kunkers stored at room temperature and plated on selective media (100%), kunkers stored at 4 C and then plated on either nonselective (91.7%) or selective (95.8%) media, kunkers stored on cold packs and then plated on either nonselective (93.8%) or selective (100%) media, kunkers stored in ampicillin solution and plated on selective media (100%), and kunkers stored in ampicillin/gentocin solution and plated on selective media (87.5%). For samples stored for 4–5 days, P. insidiosum isolation rates were highest for kunkers stored at 4 C and then plated on either nonselective (81.3%) or selective (87.5%) media, kunkers stored in ampicillin solution and then plated on selective media (87.5%), and kunkers stored in ampicillin/gentocin solution and plated on selective media (87.5%). Results of this study suggest that optimal isolation rates of P. insidiosum from infected equine tissues are achieved by culturing fresh kunkers on selective media. For samples that cannot be processed immediately, acceptable handling techniques include storage at room temperature for up to 3 days, refrigeration for up to 5 days, shipping on cold packs, and storage in antibiotic solution, each combined with subsequent inoculation on selective media.

scholarly journals Staphylococcal Food Poisoning Associated with Spray-Dried Milk

1955 ◽  
Vol 53 (4) ◽  
pp. 387-397 ◽  
Author(s):  
P. H. R. Anderson ◽  
Doris M. Stone
Keyword(s):  
Spray Drying ◽  
Clinical Features ◽  
Milk Powder ◽  
Food Poisoning ◽  
Skim Milk ◽  
Skim Milk Powder ◽  
Large Numbers ◽  
Heat Treated ◽  
Drying Chamber ◽  
Spray Dried

SummaryEight explosive outbreaks of food poisoning, occurring in school canteens in England during 1953 and affecting 1190 known cases, are described. The clinical features were characteristic of the toxin type of illness. No deaths occurred.The food causing all of these outbreaks was prepared from spray-dried skim milk powder. It was not subsequently heat-treated and was usually consumed 3–4 hr. after preparation.The spray-dried milk powder proved to contain a high content of bacteria, including large numbers of Staph. aureus, of a phage pattern often associated with food poisoning. The assumption was therefore made that these outbreaks were caused by staphylococcal enterotoxin.Because the food was often consumed within 3–4 hr. of reconstitution of the milk powder—before, in fact, the staphylococci had had time to grow—it is concluded that the poisoning must have been due mainly to pre-formed toxin.Consideration is given to the opportunities for the formation of toxin in a spray-drying plant, and reasons are brought forward for believing that it is formed mainly in the balance tank where the warm milk is kept, sometimes for several hours, before passing into the final drying chamber.The processing of the milk and the precautions for preventing contamination of the finished product are discussed.

DEVELOPMENT OF CITRUS BASED BEVERAGE UTILIZING BACOPA MONNIERI

2021 ◽  
pp. 18-19
Author(s):  
Twamoghna De ◽  
Purushottam Kumar ◽  
Jayati Pal
Keyword(s):  
Sensory Evaluation ◽  
Room Temperature ◽  
Control Sample ◽  
Leaf Extracts ◽  
Nutritional Values ◽  
Soda Water ◽  
Three Samples ◽  
Microbial Analysis ◽  
And Storage

The study was done to formulate a drink from an old medicinal herb and retain all the potential benets with a new taste and avor. For this an herbal drink was formulated and its quality ascertained. In the rst part of the study, syrup was prepared from the raw leaves of the herb with addition of acids and avors. Then this syrup was diluted further followed by carbonation with 1:3 ratio of soda water and bottled. Three samples were prepared namely, T1 (same as previous but with 1:3 ratio carbonation and dividing the sample hot lled and cold lled ). In the next part, prepared samples were subjected to sensory evaluation,chemical and microbial analysis when fresh and 0 after regular intervals at room temperature (27±1 °C) and refrigerated temperature (below 7 C). Microbial analysis of the product was done to check the quality of the herbal drink and self-life of the product. The control sample T1 cold lled was the most acceptable due to its unique taste and avor, followed by sample T1( hot lled) . The present study entailed to conclude that preparation of a drink with B. monnieri leaf extracts gives a new taste and avor with high nutritional values. This drink can be stored safe for nearly a month if carbonated and storage at refrigerated 0 temperature (below 5 C).

scholarly journals Evaluation of Two Supplemented Culture Media for Long-Term, Room-Temperature Preservation ofStreptococcus pneumoniaeStrains

2017 ◽  
Vol 2017 ◽  
pp. 1-9
Author(s):  
Beatriz Quintero Moreno ◽  
María Araque ◽  
Evelyn Mendoza
Keyword(s):  
Survival Time ◽  
Room Temperature ◽  
Culture Media ◽  
Skim Milk ◽  
Extended Period ◽  
Phenotypic Characteristics ◽  
Genetic Profiles ◽  
Sequence Types ◽  
Over Time

Objective. To produce two supplemented agar types in order to store pneumococci for several months at room temperature.Methods. Todd-Hewitt/Hemoglobin/Yeast/Charcoal/Agar (TH-HYC) and Todd-Hewitt/Skim-Milk/Yeast/Charcoal/Agar (TH-SYC) were used to prepare two supplemented agar types. Nineteen pneumococci isolated from patients or asymptomatic carriers displaying diverse serotypes and multilocus sequence types (MLST) were subcultured and stored onto supplemented agar types, in four different tests, at room temperature.Findings. At the end of all tests (4–6 months) all noncontaminated subcultures were viable and maintained all phenotypic characteristics. Survival-time curves revealed a slow decrease of viable CFU over time on agar types, but at the end the number of viable CFU was satisfactory (≥2+ of growth). Decreasing of CFU was significantly higher for clinical versus nasopharyngeal isolates. Subcultures contamination rates were 6.25% and 14.58% after 2 and 6 months of storage, respectively.Conclusion. TH-HYC and TH-SYC agar types allowed the viability of pneumococci with several serotypes, MLST, and genetic profiles, after 6 months of storage at room temperature. We consider that these agar types are a valid alternative to preserve pneumococci over an extended period, especially when methods as cryopreservation or lyophilization are not available, and are useful for transporting strains between laboratories.

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