Comparison of selective media for the enumeration of sublethally heated food-poisoning strains of Staphylococcus aureus

1974 ◽  
Vol 20 (7) ◽  
pp. 1072-1075 ◽  
Author(s):  
D. L. Collins-Thompson ◽  
A. Hurst ◽  
B. Aris
Keyword(s):  
Staphylococcus Aureus ◽  
Phosphate Buffer ◽  
Food Poisoning ◽  
Potassium Phosphate ◽  
Egg Yolk ◽  
Potassium Phosphate Buffer ◽  
Mannitol Salt Agar ◽  
Selective Media

Staphylococcus aureus strains (19 food-poisoning strains) were heated at 52C for 15 min in 100 mM potassium phosphate buffer. The sublethally heated organisms were enumerated on seven selective media commonly used for quantitating S. aureus. Compared to trypticase soy agar, Baird-Parker agar was the only medium which was satisfactory with all cultures tested. The remaining selective media gave unsatisfactory recoveries with one or more of the strains tested and are listed in the following order of decreasing acceptability: tellurite glycine agar, egg yolk azide agar, phenolphthalein phosphate agar with polymyxin, mannitol salt agar, Vogel Johnson agar.

Repair of salt tolerance and recovery of lost D-alanine and magnesium following sublethal heating of Staphylococcus aureus are independent events

1981 ◽  
Vol 27 (6) ◽  
pp. 627-632 ◽  
Author(s):  
A. Hurst ◽  
A. Hughes
Keyword(s):  
Staphylococcus Aureus ◽  
Salt Tolerance ◽  
Phosphate Buffer ◽  
Synthetic Medium ◽  
Potassium Phosphate ◽  
Complex Media ◽  
Rich Medium ◽  
Potassium Phosphate Buffer ◽  
Heat Damage ◽  
Independent Events

Sublethal heating of Staphylococcus aureus S6 in potassium phosphate buffer caused loss of salt tolerance, D-alanine, and magnesium. During incubation in rich complex media all three of the damaged sites were repaired. Repair occurred more slowly but went to completion in a dilute synthetic medium (DSM), free of D-ala. DSM plus penicillin or D-cycloserine allowed repair of salt tolerance but recovery of normal levels of D-ala or Mg was prevented. When DSM-repaired cells were cultured into fresh rich medium they grew rapidly after a short lag. Cells which had acquired their salt tolerance in DSM plus cycloserine and were D-ala and Mg deficient grew slowly and had a lag of 3 h. We suggest that heat damage has two separate primary targets in S. aureus cells: the membrane, which is manifested by loss of salt tolerance, and a second site, possibly teichoic acids, manifested by loss of D-ala and Mg.

scholarly journals Identifikasi Staphylococcus aureus pada Daging Ayam yang Dijual di Pasar Besar Kota Palangka Raya

2019 ◽  
Vol 1 (1) ◽  
pp. 13-16
Author(s):  
Rahmawati Rahmawati ◽  
Eva Apriliana ◽  
Agus Agus
Keyword(s):  
Staphylococcus Aureus ◽  
High Temperatures ◽  
Staphylococcus Epidermidis ◽  
Food Poisoning ◽  
Chicken Meat ◽  
High Protein ◽  
Mannitol Salt Agar ◽  
Selective Media ◽  
Contaminated Food

Staphylococcus aureus can be a cause of food poisoning in humans. This type of bacteria can produce enterotoxins that cause contaminated food and poisoning in humans. The toxin produced is resistant in high temperatures, although the bacteria die by heating but the resulting toxin will not be damaged and can still change despite freezing or freezing. Staphylococcus aureus is commonly found in high-protein foods such as egg and chicken products. The purpose of this study was to investigate the contamination of Staphylococcus aureus bacteria in chicken meat sold in Pasar Besar Kota Palangka Raya in 2018. The examination using MSA media (Mannitol Salt Agar) because MSA media is different selective media to differentiate Staphylococcus aureus with Staphylococcus epidermidis. The results of analysis of chicken meat in Pasar Besar Kota Palangka Raya 20% positive contaminated Staphylococcus aureus bacteria in the first-day sample. In the second day, the sample found 13.3% positive contaminated Staphylococcus aureus bacteria.

scholarly journals COMPARATIVE EVALUATION OF SIX SELECTIVE MEDIA FOR THE DETECTION AND ENUMERATION OF STAPHYLOCOCCUS AUREUS IN FOODS

1974 ◽  
Vol 25 (4) ◽  
pp. 10
Author(s):  
Β. ΑΛΜΠΑΛΑΣ
Keyword(s):  
Staphylococcus Aureus ◽  
Comparative Evaluation ◽  
Egg Yolk ◽  
Mannitol Salt Agar ◽  
Selective Media ◽  
Pure Cultures ◽  
The Media ◽  
Coagulase Positive Staphylococci ◽  
The Ideal

Six selective media for the detection and enumeration of coagulase-positive staphylococci werl ctudied evaluated for their efficiency in the recovery and easy recognition of five strains of Staphylococcus aureus. They were Mannitol Salt agar (MS', Tellurite Polymyxine Egg Yolk agar (TPEY),Egg Yolk Azide Agar (EYAA), Egg yolk Tellurite Glycine Pyruvate Agar (ETGPA). Milk Salt Agar (MSA), in combination with Salt Egg Yolk Agar (SEYA), and Vogel-Johnson agar (VJ), after enrichement in Trypticase Soy Broth 10V» NaCl.The recovery of the used strains was evaluated in pure cultures and after inoculation in various foods. None of the tested media was proved to be the ideal one. The media TPEY, ETGRA. and EYAA were considered as the nost appropriate for the detection of S. aureus in foods. The selective ability of eash medium is greatly depended on the strain and the food involved The simultaneoue use of two selective media is suggested if that is possible.

Reliability of Selective Media for Recovery of Staphylococci from Cheese

1977 ◽  
Vol 40 (1) ◽  
pp. 11-16 ◽  
Author(s):  
M. E. STILES
Keyword(s):  
Staphylococcus Aureus ◽  
Significant Interaction ◽  
Egg Yolk ◽  
Selective Medium ◽  
Selective Agent ◽  
Mannitol Salt Agar ◽  
Selective Media ◽  
Cheese Ripening ◽  
Different Strains ◽  
Blood Agar Base

The reliability of 12 selective media for recovery of four different strains of Staphylococcus aureus inoculated at manufacture into three cheese types was determined. Selective medium and time of ripening had a highly significant effect (p < 0.001) on reliability of the staphylococcal count. In addition, highly significant interaction effects were observed. The most reliable medium in the overall analysis was mannitol salt agar. However, this medium was not equally reliable at all times during ripening, and use of both mannitol salt agar and Staphylococcus medium no. 110 is recommended. The tellurite- and azide-based selective media were generally unsatisfactory, however tellurite glycine agar, Vogel Johnson (VJ) agar, and azide blood agar base were totally unreliable. In general, the salt-based selective media were most reliable. This applied also to the egg yolk media that use salt as the selective agent. Salt egg yolk agar and Colbeck's egg yolk medium generally gave higher recoveries of S. aureus than did Baird-Parker medium, Crisley et al. tellurite polymyxin egg yolk agar, and Hopton egg yolk azide agar, except in the unripened cheeses. The debilitating effect of cheese ripening on the staphylococcal cells was not eliminated by the egg yolk tellurite and azide media.

scholarly journals Protecting ultra- and hyperhydrophilic implant surfaces in dry state from loss of wettability

2016 ◽  
Vol 2 (1) ◽  
pp. 557-560 ◽  
Author(s):  
Steffen Lüers ◽  
Markus Laub ◽  
Herbert P. Jennissen
Keyword(s):  
Dental Implants ◽  
Phosphate Buffer ◽  
Potassium Phosphate ◽  
Optimal System ◽  
Potassium Phosphate Buffer ◽  
Long Time ◽  
Optical Appearance

AbstractUltrahydrophilic titanium miniplates with sandblasted and acid etched (SLA) surfaces were protected from loss of hydrophilicity by an exsiccation layer of salt and stored in a dry state. Various salts in different concentrations were tested in respect to their conservation capacity and optical appearance. Potassium phosphate buffer in a specified composition appeared to be optimal. This optimal system was applied in a long time storage experiment showing no loss of hydrophilicity over years. It was also transferred with success to hyperhydrophilic dental implants.

scholarly journals An Elution Procedure for Visualization of Adult Hemoglobins in Human Blood Smears

Blood ◽  
1974 ◽  
Vol 43 (2) ◽  
pp. 239-242 ◽  
Author(s):  
David Kabat
Keyword(s):  
Cord Blood ◽  
Human Blood ◽  
Phosphate Buffer ◽  
Newborn Infants ◽  
Potassium Phosphate ◽  
Fetal Hemoglobin ◽  
Potassium Phosphate Buffer ◽  
Blood Smears

Abstract A procedure is described for visualization of normal and mutant adult hemoglobins in human blood smears. After extraction of blood smears with a concentrated potassium phosphate buffer (2.76 M, pH 7.2), erythrocytes that had adult hemoglobins stained bright red with erythrosin, whereas cells that had only fetal hemoglobin appeared as clear ghosts. Analyses of cord blood from newborn infants indicate that, although most erythrocytes contain only Hb F and a few contain only Hb A, many contain both hemoglobins A and F.

scholarly journals Studies on the growth and survival ofStaphylococcus aureusin corned beef

1983 ◽  
Vol 91 (3) ◽  
pp. 467-478 ◽  
Author(s):  
J. M. Mansfield ◽  
G. Farkas ◽  
Antonnette A. Wieneke ◽  
R. J. Gilbert
Keyword(s):  
Staphylococcus Aureus ◽  
Ambient Temperature ◽  
Uniform Distribution ◽  
Food Poisoning ◽  
Growth And Survival ◽  
Selective Media ◽  
Rate Of Spread

SUMMARYThe growth of an enterotoxin A producing strain ofStaphylococcus aureusin corned beef was investigated. In the inoculated 6 lb. canned product the bacteria spread throughout the meat and attained high numbers. The rate of spread of the organisms was related to the temperature and length of storage of the cans and the numbers of bacteria inoculated. Cans which had been stored for more than four months showed high counts of the bacteria throughout the meat. It was noted that with the long term contaminated product counts ofS. aureuson some selective media may give falsely low results.Numbers ofS. aureuson meat inoculated by handling after removal from the can were initially extremely variable. More uniform distribution and higher counts were attained only if the meat was exposed for some hours at ambient temperature or above. The significance of the results to the investigation of outbreaks of food poisoning suspected of being associated with canned corned beef is discussed.

scholarly journals Purification and general properties of δ-aminolaevulate dehydratase from Nicotiana tabacum L.

1969 ◽  
Vol 114 (2) ◽  
pp. 331-337 ◽  
Author(s):  
A. S. Shetty ◽  
G. W. Miller
Keyword(s):  
Activation Energy ◽  
Nicotiana Tabacum ◽  
Phosphate Buffer ◽  
Potassium Phosphate ◽  
Optimum Temperature ◽  
Thiol Groups ◽  
Potassium Phosphate Buffer ◽  
Tobacco Leaves ◽  
General Properties ◽  
Nicotiana Tabacum L

1. δ-Aminolaevulate dehydratase (EC 4.2.1.24) was purified 80-fold from tobacco leaves and its properties were studied. 2. The enzyme had optimum pH7·4 in potassium phosphate buffer, Km6·25×10−4m at 37° and pH7·4, optimum temperature 45° and an activation energy of 11100 cal./mole. 3. The enzyme lost activity when prepared in the absence of cysteine, and this activity was only partly restored by the later addition of thiols. Reagents for thiol groups inactivated the enzyme. 4. Mg2+ was essential for activity, and EDTA and Fe2+ were inhibitory; Mn2+ was an activator or an inhibitor depending on the concentration.

Factors that Influence Germination and Mycoherbicidal Activity ofAlternaria cassiae

1991 ◽  
Vol 5 (1) ◽  
pp. 82-86 ◽  
Author(s):  
Donald J. Daigle ◽  
Peter J. Cotty
Keyword(s):  
Relative Humidity ◽  
Phosphate Buffer ◽  
Potassium Phosphate ◽  
Tween 80 ◽  
Growth Chamber ◽  
Potassium Phosphate Buffer ◽  
Potato Dextrose Broth ◽  
Leaf Stage ◽  
True Leaf

The influences of pH, surfactants, and nutrients on germination were investigated to develop a basis for improvement ofAlternaria cassiaemycoherbicide formulations. In vitro results indicated that a formulation with a pH of approximately 6.5 containing 0.1 to 1% Tween 80, 0.02 M potassium phosphate buffer, and 1% dehydrated potato dextrose broth best promoted germination. Sicklepod plants at the 2 to 3 true-leaf stage were sprayed with test solutions, incubated in the dark at 100% relative humidity (28 C) for 6 h, and placed in a growth chamber maintained at 30 C. Assessment of the plants after 2 d indicated that the ability of the formulation components to induce germination ofAlternaria cassiaein vitro corresponded well with their ability to improve infection of sicklepod seedlings.

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