Résistance de souches bactériennes isolées de lait d’ânesse aux hostilités digestives simulées in vitro

الموضوعات

علوم بحتة وطبيعية

الملخص

The aim of this work was to characterize lactic strains isolated from donkey milk byidentifying them and testing their growth potential (at different salt concentrations anddifferent temperatures) and their ability to withstand in vitro simulated digestive hostilities asa criterion for eligibility for "probiotic" status. The results obtained showed that the nine lacticstrains isolated from the donkey milk used in this work keep growing at 10, 45 or 63.5 °C andin the presence of 2.4 and 6.5% (w / v) NaCl. They also display a differential resistancecapacity depending on the strain type under the conditions of the digestive tract simulated bysalivary α-amylase, acidity and gastric secretion, bile salts, lysozyme and pancreatic enzymes(pancreatin, lipase, amylase and proteases). Thus, the strains are initially sensitive to salivaryα-amylase but recover growth again after the first 30 minutes of exposure. All strains areslowed in their growth by simulated gastric acidity at levels between 25 and more than 40%.There were 2 strains (S1 and S2) out of 9 tested whose bile salt and lysozyme survival wassignificantly (p <0.05) reduced by 35%. Exposure of lactic acid strains for 5 hours topancreatic enzymes did not significantly alter their survival, the lowest (around 80%) wasrecorded for strains S1, S3 and S7 whereas other strains kept growing giving rise to more than100% of survival. It is the S8 strain that has the most resistance to proteases. S5 and S8 strainswere the most resistant strains to the digestive tract conditions, and therefore were selected formolecular identification by MALDI TOF, which revealed that they belong to the genusEnterococcus. Analysis of the MALDI TOF mass spectra have shown that the two strains (S5and S8) belong to the same species which is the species faecium with scores of 2.40 for S5and 2.36 for S8.

روابط وملفات

التعريف والنوع

رقم الوثيقة

eb719f73-87f8-4edf-a947-5c3552eff3cb

رقم العقد

0

نوع الوسائط

Crawler

نوع المحتوى

الرسائل العلمية

صيغة المصدر

ماستر (LMD)

نوع الملف

pdf text

أسماء الملفات

2056049_1.pdf

بيانات النشر

ألقاب المؤلفين

[{"name_ar":" A. Riazi ","title_ar":"اشراف","title_en":"Supervision"},{"name_ar":" Yasmina Haddad","title_ar":"اعداد","title_en":"Preparation"}]

اللغة

French

المصدر والدورية

اسم المصدر

Résistance de souches bactériennes isolées de lait d’ânesse aux hostilités digestives simulées in vitro

المحتوى والصفحات

عدد الصفحات

0

إشراف وإعداد

الإشراف

A. Riazi

الإعداد

Yasmina Haddad

الاقتباسات الببليوغرافية