عزل بكتريا Bacillus cereus من بعض عينات الغذاء == Isolation of Bacillus Cereus From Some Foods Samples
Author name:
ضحى عبد الله كاظم الظويهري
Supervisor name:
حبيب صاحب نهر
General topic:
Medicine
Specific topic:
Microbiology
Degree:
Master
University:
University of Babylon - Faculty Of Medicine - Department Of Microbiology
Language:
English
University location:
Babylon
First pages:
19T1120 - p.pdf
Abstract:
كائن Bacillus cereus موجود في كل مكان وهوممرض منقول بالاغذية والذي يمكن ان يسبب نوعين من امراض الجهاز الهضمي : القيء والاسهال. في هذه الدراسه, تم جمع 140 عينه غذائية شملت (الرز, اغذية الاطفال، الدقيق، منتجات الالبان، اللحوم، الحليب , التوابل) جمعت عشوائيا | Bacillus cereus is a ubiquitous organism and a potential foodborne pathogen that can cause two types of gastrointestinal diseases : emesis and diarrhea. In this study, a total of 140 food samples included (rice, infant food, flour, dairy products, meat, milk powder and spices) were collected randomly from restaurants, food stores and various sale points in the local markets of the Hilla province during the period of November 2014 to April 2015 in attempt to isolate of Bacillus cereus from these samples and detection the prevalence of diarrheal (hbl and nhe) and emetic (ces) enterotoxins genes by using Polymerase Chain Reaction (PCR). All bacterial isolates were identified by cultural, microscopic and biochemical examinations. The results showed that 56 (40%) of samples showed positive growth for Bacillus cereus. The antibiotic sensitivity test of some isolates to 10 antibiotics was studied. It has been found that all B. cereus isolates were resistant to Ampicillin, Ampiclox, Cefotaxime, and Cephalexin, while all isolates were sensitive to Gentamycin, Ciprofloxacine and Chloramphenicol, but most of them showed different rate of sensitivity to one or more of antibiotics such as Neomycin 90% and 80% for both Tetracycline and Erythromycin. Polymerase Chain Reaction technique (PCR) was used to detect the ability of bacterial isolates to encode two types of enterotoxin genes, diarrheal and emetic genes. The results showed that 4(7.14 %) of isolates harboured hblA gene, 16 (28.57%) hblC, 5(8.92 %) hblD, 46(82.14%) nheA, 24(42.85%) nhe B, 26 (46.42%) nheC and 3(5.35%) of the isolates harboured Ces gene. On the other hand, through using PCR it was found that nhe gene was present in most isolates, while hbl gene was variable among the studied isolates. Moreover, the Ces gene was found only in isolates being isolated from rice samples, while it was not found in other types of samples.
