الكشف عن جراثيم Geobacillus stearothermophilus في بعض العينات الغذائية باستعمال التقانات الجزيئية وإنتاج الإنزيم أليف الحرارة

الموضوعات

علوم بحتة وطبيعية

روابط وملفات

التعريف والنوع

رقم الوثيقة

eea644e8-d4b9-4053-bf27-a8ddd3017f77

رقم العقد

0

نوع الوسائط

Crawler

نوع المحتوى

الرسائل العلمية

صيغة المصدر

رسائل ماجيستير

نوع الملف

pdf text

أسماء الملفات

1961166_1.pdf

بيانات النشر

ترجمة العنوان

Detection of Geobacillus stearothermophilus bacteria in some food samples using molecular technology and production of a thermophilic enzyme

ألقاب المؤلفين

[{"name_ar":"أيمن المريري","title_ar":"اشراف","title_en":"Supervision"},{"name_ar":"رشا محمد هادي الأبرص","title_ar":"اعداد","title_en":"Preparation"},{"name_ar":"كمال الأشقر","title_ar":"اشراف","title_en":"Supervision"}]

اللغة

Arabic

المصدر والدورية

اسم المصدر

الكشف عن جراثيم Geobacillus stearothermophilus في بعض العينات الغذائية باستعمال التقانات الجزيئية وإنتاج الإنزيم أليف الحرارة

المحتوى والصفحات

عدد الصفحات

0

ترجمة الملخص

Thermophilic Geobacillus spp. bacteria are widely distributed in nature and commonly associated with a variety of food products. Endospore formation provides these bacteria the resistance to sterilization and pasteurization treatments which made it the most important causes of food spoilage .Variable food samples including milk, canned food, tomato paste and ketchup were collected from Damascus City to isolate G.stearo thermophilus. 200 thermophilic bacterial isolates were detected due to their growth at 60 ºC, all these isolates were identified according to their morphological and cultural characteristics and biochemical tests.Results showed that 35 of these isolates were diagnosed as Geobcillus stearothermophilus with a percentage of 17.5%. Polymerase Chain Reaction (PCR) was used to assert these results using two primer pairs which were designed for the first time to amplify a specific conservedgenes like the 16S rRNA gene that identified the genus Geobcillus in length of 275 bpand recNgenethat identified of species within the genus 650 bp.29 bacterial isolates were cable to produce lipase enzyme using Tributyrinmedium containing 1% olive oil and forming clear zones around the colonies. The isolate 173 which showed the highest hydrolyses efficiency (200%) was chosen for optimization of lipase production by studying the effect of different parameters such as incubation period, temperature, initial medium pH, carbon and nitrogen sources and different concentration of olive oil. The results showed that the highest lipase production (71 U/ml) was after 48 h of incubation at temperature 50º C and initial medium pH 9.0,and using glucose as carbon source and peptone as a nitrogen source and the olive oil in the concentration of 2%. The expression of the recombinant lipase enzyme was done by the amplification of lipgene encoded lipase enzyme using PCR reaction and cloning it into expression vector pET-15b, then transformation this recombinant plasmid (pET-15b-lip) into E. coliBL21(DE3) after that, the expression method was done by adding the inducer IPTG (1mM) for (4-18-24 h) . This enzyme was purified by HIC chromatography using Hi-Trap Q-sepharose columin. SDS-PAGE analysis showed a single protein band with a molecular weight of 29 kD which referred to the purified enzyme.

إشراف وإعداد

الإشراف

أيمن المريري, كمال الأشقر

الإعداد

رشا محمد هادي الأبرص

الاقتباسات الببليوغرافية