Effect of Temperature on the Expression of Classical Enterotoxin Genes among Staphylococci Associated with Bovine Mastitis

Staphylococcal food poisoning (SFP), caused by the contamination of staphylococcal enterotoxins, is a common foodborne disease worldwide. The aims of this study were: (1) to investigate classical staphylococcal enterotoxin genes, sea, seb, sec, sed, and see, among Staphylococcus aureus and coagulase-negative staphylococci (CNS) associated with bovine mastitis; (2) to determine the effect of temperature on the expression of classical staphylococcal enterotoxin genes in staphylococci in milk. The detection of classical staphylococcal enterotoxin genes was performed using S. aureus (n = 51) and CNS (n = 47). The expression of classical enterotoxin genes, including sea, seb, sec, and see, was determined during the growth of staphylococci in milk subjected to ultra-high-temperature processing at two different temperatures: 8 °C and room temperature. Classical staphylococcal enterotoxin genes were expressed more frequently in S. aureus (35.30%) than in CNS (12.77%). The sec gene was most frequently detected in S. aureus (29.41%) and CNS (6.38%). Moreover, the expression of sea and sec was significantly higher at room temperature than at 8 °C after 16 h of incubation (p < 0.05). These results emphasize the importance of maintaining the storage temperature of milk below 8 °C to reduce the risk of SFP.

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Effect of temperature and scarification on germination and emergence of wild safflower, Carthamus oxyacantha Bieb.

The Journal of Agricultural Science ◽

10.1017/s0021859600052345 ◽

1975 ◽

Vol 84 (2) ◽

pp. 239-243 ◽

Cited By ~ 7

Author(s):

A. Bassiri ◽

I. Rouhani ◽

S. R. Ghorashy

Keyword(s):

Seedling Growth ◽

Room Temperature ◽

Laboratory Experiments ◽

Germination Percentage ◽

Effect Of Temperature ◽

Silty Clay ◽

Wild Type ◽

Different Temperatures ◽

Wild Safflower ◽

Wild Seed

SUMMARYSeeds of wild safflower, Carthamus oxyacantha Bieb., collected from the Bajgah area, Iran, were subjected to chilling and/or scarification and their germination and emergence characteristics and seedling growth were studied in two laboratory experiments. Seeds of Arak 2811 variety of cultivated safflower, C. tinctorius L., harvested from the same area at the same time was used for comparison.In the first experiment, the untreated, scarified, chilled at 0 °C for 1 month, and chilled and scarified wild seed and seed of the variety Arak 2811 were incubated at six different temperatures (5, 10, 15, 20, 25 and 30 °C) and their germination percentage and seedling lengths were recorded. In the second experiment, the seeds of the above five treatments were planted in a silty clay loam at room temperature (23 ± 2 °C) and their emergence and seedling heights were noted.In all cases, the cultivated variety, Arak 2811, had higher germination and emergence percentages and seedling heights than the wild type. Germination of both strains was greatly reduced at the two extreme temperatures (5 and 30 °C). The optimum temperatures for germination of the wild and the cultivated strains were between 15 and 20 °C.Scarification of the wild seed did not improve the germination or emergence percentages and chilling of the seed for a month at 0 °C reduced the emergence of the wild seed. Temperature of germination, however, seemed to be an important factor affecting germination and seedling growth of wild safflower.

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The effect of temperature change on fluoride uptake from a mouthrinse by enamel specimens

European Journal of Dentistry ◽

10.1055/s-0039-1698973 ◽

2012 ◽

Vol 06 (04) ◽

pp. 361-369 ◽

Cited By ~ 1

Author(s):

Serdar Baglar ◽

Adil Nalcaci ◽

Mustafa Tastekin

Keyword(s):

Body Temperature ◽

Room Temperature ◽

Hot Water ◽

Effect Of Temperature ◽

Distilled Water ◽

Fluoride Solution ◽

Fluoride Uptake ◽

Significant Difference ◽

Human Body Temperature ◽

Different Temperatures

ABSTRACTObjective: The aim of this study was to examine the effect of temperature on fluoride uptake by enamel specimens from a 0.05% NaF-fluoridated mouthrinse (Oral-B Advantage; Oral-B Laboratories, Newbridge, UK).Methods: Enamel specimens were prepared from extracted human maxillary central incisors. A fluoride-specific ion electrode was used to measure the uptake from a 2 ppm fluoride solution containing 50.0 mL of distilled water, total ion strength adjustment buffer, and fluoridated rinse at 3 different temperatures (room temperature, 25°C; human body temperature, 37°C; hyper-fever temperature, 43°C). One-way analysis of variance and least significant difference were used to assess intragroup and intergroup differences (P<.05).Results: The study found that both the amount and the rate of fluoride uptake increased significantly with increase in temperature. This effect was particularly noticeable at 43°C.Conclusions: The temperature of the NaF mouthrinse may easily and safely be increased beyond room temperature by placing a container of the NaF mouthrinse in a bowl of hot water, allowing greater fluoride penetration into the enamel from the mouthrinse when used at home as a routine prophylactic agent. (Eur J Dent 2012;6:361-369)

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Refinement of 2-Amino-6-(4-methyl-1-piperazinyl)-4-(tricyclo[3.3.1.13,7]dec-1-yl)-1,3,5-triazine at Three Different Temperatures using Image-Plate Data

Journal of Applied Crystallography ◽

10.1107/s0021889896000180 ◽

1996 ◽

Vol 29 (3) ◽

pp. 261-264 ◽

Cited By ~ 1

Author(s):

A. Perrakis ◽

T. R. Schneider ◽

E. Antoniadou-Vyzas ◽

Z. Dauter ◽

S. J. Hamodrakas

Keyword(s):

Small Molecule ◽

Room Temperature ◽

Effect Of Temperature ◽

Image Plate ◽

Rotation Method ◽

Different Temperatures ◽

Using Data

The structure of 2-amino-6-(4-methyl-1-piperazinyl)-4-(tricyclo[3.3.1.13,7]dec-1-yl)-1,3,5-triazine was refined using data collected at three different temperatures [room temperature (293 K), 150 K and 85 K] with the use of an image-plate scanner in an attempt to study the effect of temperature on the disorder of the adamantyl group. It is demonstrated that the data collected with the rotation method and an image-plate scanner are of a high enough quality to be used for the refinement of small-molecule structures.

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Atypical Toxigenic Staphylococcus and Non-Staphylococcus aureus Species on the Horizon? An Update†

Journal of Food Protection ◽

10.4315/0362-028x-59.10.1123 ◽

1996 ◽

Vol 59 (10) ◽

pp. 1123-1126 ◽

Cited By ~ 25

Author(s):

REGINALD W. BENNETT

Keyword(s):

Staphylococcus Aureus ◽

Food Poisoning ◽

Staphylococcal Enterotoxin ◽

Foodborne Illness ◽

Coagulase Negative Staphylococci ◽

Rapid Methods ◽

Staphylococcal Species ◽

Enterotoxin Production

Staphylococcal food poisoning is a commonly reported illness caused by the ingestion of preformed staphylococcal enterotoxin in foods, With some exceptions, enterotoxin production is associated with coagulase-positive rather than coagulase-negative staphylococci. Of the coagulase-positive staphylococcal species, S. aureus was historically thought to be exclusively implicated in human foodborne illness. More recently, however, other coagulase-positive and some coagulase-negative staphylococcal species have been associated with foodborne intoxication, Coagulase activity has been used to indicate pathogenicity of a foodborne isolate, and thermostable nuclease is being suggested as a more reliable indictor of enterotoxigenicity. Evidence suggests that the metabolic expressions that are the bases of the tests may not be reliable indicators of pathogenicity. A more useful approach to determine the pathogenicity of a Staphylococcus species is to test directly for enterotoxigenicity with one of the new rapid methods. None of the conventional ancillary identification tests has been conclusively associated with enterotoxin synthesis. Furthermore, evidence exists that enterotoxin production is a characteristic of several species in the genus Staphylococcus.

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Pengaruh Suhu Penyimpanan Terhadap Kerusakan Spora Myxobolus koi [The Effect of Storage Temperature in Myxobolus koi Spore Damage]

Jurnal Ilmiah Perikanan dan Kelautan ◽

10.20473/jipk.v11i1.12270 ◽

2019 ◽

Vol 11 (1) ◽

pp. 28

Author(s):

Gunanti Mahasri ◽

Titom Gusmana Putra Perdana ◽

Kusnoto Kusnoto

Keyword(s):

Data Analysis ◽

Main Parameter ◽

Room Temperature ◽

Storage Temperature ◽

Design Method ◽

Optimum Temperature ◽

Randomized Design ◽

Damage Data ◽

Different Temperatures ◽

Completely Randomized Design

AbstrakSpora Myxobolus koi dapat mengalami kerusakan apabila disimpan dalam kondisi penyimpanan yang kurang baik. Penelitian ini bertujuan untuk mengetahui pengaruh suhu penyimpanan terhadap kerusakan spora Myxobolus koi serta untuk mengetahui suhu optimum untuk penyimpanannya. Penelitian ini dilakukan dengan metode rancangan acak lengkap (RAL) sebagai rancangan percobaan. Perlakuan yang digunakan adalah penyimpanan spora Myxobolus koi pada suhu kamar (28-34) oC, Refrigerator (2-4) oC, dan Freezer (-5 hingga -10) oC, dengan ulangan sebanyak 6 kali. Penyimpanan ini dilakukan selama 30 hari. Parameter utama yang diamati adalah prosentase spora Myxobolus koi yang rusak. Parameter penunjang yang diamati adalah tipe kerusakan spora Myxobolus koi. Analisis data menggunakan ANAVA (Analisis Varian) dan dilanjutkan dengan Uji Jarak Berganda Duncan untuk mengetahui suhu optimum untuk penyimpanan spora Myxobolus koi. Berdasarkan hasil penelitian diketahui bahwa peyimpanan pada suhu yang berbeda berpengaruh terhadap prosentase kerusakan spora Myxobolus koi. Kerusakan spora Myxobolus koi tertinggi terjadi pada suhu kamar (28-34) oC mencapai angka 68,91% dan nilai kerusakan terrendah terjadi pada refrigerator (2-4) oC yaitu 29,91%. Spora Myxobolus koi dapat disimpan pada refrigerator dan lemari pembeku. AbstractMyxobolus koi spores can be damaged if stored in poor conditions. This study aimed to determine the effect of storage temperature on Myxobolus koi spores and to determine the optimum temperature for storage. This research was conducted using a completely randomized design method (CRD) as an experimental design. The treatments used were storaged Myxobolus koi spores at room temperature (28-34oC), Refrigerator (2-4oC), and Freezers (-5 to -10oC), with replications 6 times. This storage was carried out for 30 days. The main parameter observed was the percentage of damaged Myxobolus koi spores. The supporting parameters observed were the type of Myxobolus koi spore damage. Data analysis using ANAVA (Analysis of Variance) and continued with Duncan’s Multiple Distance Test to find out the optimum temperature for storage of Myxobolus koi spores. Based on the results of the study, it was found that storage at different temperatures affected the percentage of damage to Myxobolus koi spores. The highest damage of Myxobolus koi spores occurred at room temperature (28-34oC) reaching 68.91% and the lowest damage value occurred at refrigerator (2-4oC) which was 29.91%. Myxobolus koi spores can be stored in a refrigerator and freezer

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STUDY OF THE SURVIVAL OF BACILLUS CEREUS IN LOW-ACID CANNED VEGETABLES

AGROFOR ◽

10.7251/agreng1903120y ◽

2019 ◽

Vol 4 (3) ◽

Author(s):

Zinaida YEGOROVA ◽

Anastasia NIKITENKO

Keyword(s):

Experimental Data ◽

Storage Temperature ◽

Food Poisoning ◽

Practical Interest ◽

Vegetable Products ◽

Test Microorganism ◽

Different Temperatures ◽

Canned Vegetables ◽

Carrot Puree ◽

Industrial Samples

The species B. cereus is widely distributed in food products and is often the cause of food poisoning. Therefore, data on the ability of this microorganism to develop in low-acid canned products are of scientific and practical interest. The aim of the study was to determine the survival of B. cereus in low-acid canned vegetables stored at different temperatures. The objects of the study were industrial samples of aseptic canned carrot puree (pH = 5.11, aw = 0.912) and sliced beets sterilized in vacuumized polymer bags (pH = 5.43, aw = 0.887). The B. cereus 11778 strain was used. The listed products were contaminated daily culture of the test-strain, with a concentration of 104–105 CFU/ml, and incubated at 6 and 30°C for 26 days. Sampling of products was carried out every 3 days to identify viable microorganisms. The generally accepted methods of experimental microbiology were used. It was found that in the canned “Beet sliced” B. cereus died after 10 days of storing the product at a temperature of 30°C. At a storage temperature of the contaminated product equal to 6°C, the test-microorganism did not die during the whole experiment and was detected in the amount of tens CFU in 1 ml of the product. In aseptic canned carrot puree, regardless of the storage temperature, B. cereus remained viable throughout the experiment, i. e. 26 days. The approximation of the obtained numerical values showed acceptable convergence of the curves with experimental data (R2 = 0.9186 ÷ 0.985). Microscopic examination of Gram-stained B. cereus 11778 preparations isolated from contaminated samples of canned products during the experiment showed abundant sporulation of the teststrain. The research results can be used to predict the activity of B. cereus in canned vegetable products under various environmental conditions.

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Enterotoxigenic Potential of Coagulase-Negative Staphylococci from Ready-to-Eat Food

Pathogens ◽

10.3390/pathogens9090734 ◽

2020 ◽

Vol 9 (9) ◽

pp. 734

Author(s):

Wioleta Chajęcka-Wierzchowska ◽

Joanna Gajewska ◽

Patryk Wiśniewski ◽

Anna Zadernowska

Keyword(s):

Toxic Shock Syndrome ◽

Food Poisoning ◽

No Production ◽

Toxic Shock ◽

Coagulase Negative Staphylococci ◽

Staphylococcal Enterotoxins ◽

Food Borne ◽

Enterotoxin Genes ◽

Toxic Shock Syndrome Toxin ◽

Coagulase Positive Staphylococci

Although coagulase-positive staphylococci are considered to be the main factor responsible for food poisoning, an increasing role for the coagulase-negative staphylococci in the production of enterotoxins has been observed in recent years. This study was conducted to assess the occurrence of genes responsible for the production of staphylococcal enterotoxins (SE), enterotoxin-like toxins (SEI) and toxic shock syndrome toxin-1 (TSST-1) in coagulase-negative staphylococci (CoNS) isolated from ready-to-eat food from bars and restaurants. One hundred and eighteen CoNS strains were tested using polymerase chain reaction (PCR) to five superantigenic toxin genes, including five different types of classical enterotoxins (sea, seb, sec, sed and see) and the toxic shock syndrome toxin-1 (tsst-1) as well as to supertoxin-like genes. PCR-positive isolates were then tested using immunoenzymatic methods (SET-RPLA, Vidas SET 2) for toxin expression. Out of 118 CoNS strains, the presence of staphylococcal enterotoxins was confirmed in 72% of them. The most frequently found enterotoxin-like genotype was ser, selu. Two of the tested strains had up to ten different enterotoxin genes in the genome at the same time. Although no production of enterotoxins was detected in the CoNS, which means that their possible role in the epidemiology of food-borne diseases is minimal, the data demonstrated that the toxigenic capacity of the CoNS should not be ignored, and that this group of microorganisms should be continuously monitored in food.

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The Cutting Resistance of Rock Salt in Function of Temperature

New Trends in Production Engineering ◽

10.2478/ntpe-2020-0017 ◽

2020 ◽

Vol 3 (1) ◽

pp. 211-220

Author(s):

Krzysztof Kotwica ◽

Grzegorz Stopka

Keyword(s):

Rock Salt ◽

Room Temperature ◽

Underground Mines ◽

Effect Of Temperature ◽

Cutting Resistance ◽

The Road ◽

Salt Sample ◽

Mechanical Methods ◽

Different Temperatures ◽

Salt Deposits

AbstractCurrently over then 16 percent of the total worldwide salt production is excavated in underground mines. Salt deposits often lie at great depths up to 1000 m, where the temperature of the surrounding rocks reaches 50°C and even exceeds it. A large part of it is exploited using mechanical methods, mainly with the use of road headers and continuous miners. When excavating salt rock, the cutters of the road header mining head come into contact with the rock. This generate friction and in consequence a rise in temperature. In AGH University of Science and Technology the laboratory tests were carried out to determine the effect of temperature on cutting resistance and selected mechanical properties of rock salt. On the special laboratory test stand the rock salt sample was cutted at three different temperatures - 20, 50 and 80°C. The cuttability index and the side chipping angle were measured for each temperature. Additionally the same tests were performed in the case of salt sample after cooling to room temperature. The selected mechanical parameters of rock salt - compressive, tensile and shear strength were also measured for the same temperature values. The obtained results were compared and described in the paper.

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EFFECTS OF STORAGE CONDITIONS AND PRESENCE OF FRUITING BRACTS ON THE GERMINATION OF ATRIPLEX HALIMUS AND SALSOLA VERMICULATA

Experimental Agriculture ◽

10.1017/s0014479797000021 ◽

1997 ◽

Vol 33 (2) ◽

pp. 149-155 ◽

Cited By ~ 16

Author(s):

A. E. OSMAN ◽

F. GHASSALI

Keyword(s):

Seed Germination ◽

Cold Storage ◽

North Africa ◽

Room Temperature ◽

Storage Temperature ◽

Seed Storage ◽

Storage Conditions ◽

Shrub Species ◽

Atriplex Halimus ◽

Different Temperatures

Two shrub species, Atriplex halimus L. and Salsola vermiculata L., are considered useful for rehabilitation of degraded rangelands in west Asia and north Africa. They can be established from direct seeding and are capable of self-sowing. In this study, seed storage at different temperatures and the influence of fruiting bracts on seed germination were examined for the two species during two seasons. Fruits (utricles) were stored at 20–22°C (room temperature), 0°C or −22°C. Germination tests were carried out after 33, 56, 90, 152, 272 and 397 d in storage in the first season and after 44, 76, 104, 170, 288 and 412 d in the second season. Seeds were germinated in their fruiting bracts or after bract removal. Bract removal significantly improved seed germination of both shrubs regardless of storage temperature. For S. vermiculata the increase in germination was in the range of 1.3- to 14.7-fold compared with values for the intact fruit in Season 1 and 0.5 to 3.8 in Season 2. Similarly the ranges for A. halimus were 0.5- to 4.2-fold and 0.7- to 5.3-fold in the two seasons respectively. The effect of cold storage was greater on Salsola than on Atriplex. The reduction of the storage temperature from 21°C to 0°C and −22°C increased the longevity of S. vermiculata seeds by 2.8–46.6 times in Season 1 and by 2.9–2.6 times in Season 2. There was little or no effect on the longevity of A. halimus. A leachate prepared by soaking fruiting bracts from S. vermiculata significantly depressed germination (p < 0.01), the effect being greater on Salsola seeds (20% reduction) than on Atriplex seeds (8% reduction). A leachate from A. halimus produced a slight but non-significant reduction in germination.

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