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العنوان
Risk assessment of staphylococcus aureus enterotoxin a in meat /
الناشر
Heba Abdelmoneim Abdelbary Abdelghany ,
المؤلف
Heba Abdelmoneim Abdelbary Abdelghany
هيئة الاعداد
باحث / Heba Abdelmoneim Abdelbary Abdelghany
مشرف / Nabil Abdelgabar Yassien
مشرف / Hamdy Mohamed Bakry
مشرف / Khalid Shawky Tolba
تاريخ النشر
2019
عدد الصفحات
65 P. :
اللغة
الإنجليزية
الدرجة
الدكتوراه
التخصص
Food Animals
تاريخ الإجازة
9/10/2019
مكان الإجازة
جامعة القاهرة - كلية الطب البيطري - Food Hygiene and Control
الفهرس
Only 14 pages are availabe for public view

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from 131

Abstract

The Staphylococcus aureus enterotoxin A (SEA) is the toxin mostly involved in Staphylococcus aureus (S. aureus) food poisoning. In this study, the effect of different lactic acid (LA) concentrations (LA 1% and 2%), lysozyme concentrations (100 mg/ml and 200 mg/ml) and temperatures (4{u00B0}C, 25oC, and 37{u00B0}C) on S. aureus growth and relative sea expression in fresh meat cuts were studied. Real-Time PCR (RT-PCR) was used to determine relative sea expression. Fresh meat cuts were inoculated with 105 CFU/g of S. aureus producing enterotoxin A. Thus, S.aureus growth and relative sea expression were regularly tested for 48 hours. The growth of S. aureus was decreased by one log CFU/g than control sample using 1% LA and 2% LA (5.32 ± 3.76 log CFU/g, 4.38 ± 3.00 log CFU/g and 4.54 ± 3.18 log CFU/g respectively) while, the use of 100 mg/ml and 200 mg/ml lysozyme decreased the counts to be 4.95 ± 3.77 log CFU/g and 4.98 ± 3.99 log CFU/g, respectively. Relative expression of the sea gene in both lysozyme and LA concentrations was lower than control. Moreover,both lactic acid and lysozyme concentrations had an effect on relative sea gene expression at all examined hours, especially at 4{u00B0}Ccompared to control samples.The higher the lactic acid concentration, the lower the S. aureus enterotoxin A relative expression was, lysozyme as well