Biocontrol Of Listeria Monocytogenes In A Model Cultured Milk (Lben) By In Situ Bacteriocin Production From Lactococcus Lactis Ssp Lactis

Bacteriocin-producing (Bac+) Lactococcus lactis ssp. lactis CCMM/IAV/BK1 isolated from traditional lben was used in the preparation of lben from pasteurized milk to assess its potential inhibitory activity against Listeria monocytogenes ATCC 7644. Production of bacteriocin (arbitrary units, AU) in MRS broth fortified with yeast extract (MRSY) in a fermentor under controlled and uncontrolled pH conditions was also investigated. This Bac+ strain yielded about 35 times more bacteriocin when the pH was maintained constant at 6.5 than under varying pH conditions. To test the effect of in situ bacteriocin production against L. monocytogenes, lben was made from cow's milk artificially contaminated with approximately 107 cfu/mL and fermented with a mixed mesophilic starter culture consisting of the lactococcal Bac+ organism and Lc. lactis ssp. lactis biovar diacetylactis 66, a diacetyl-producing strain, in a ratio of 1 : 1. Numbers of L. monocytogenes were monitored during fermentation and storage of lben at refrigeration temperature (c. 7°C) for up to 6 days. Performances of the Bac+ starter were compared to those of an isogenic Bac- derivative strain obtained from the Bac+ starter by curing with ethidium bromide. The results showed that the amount of L. monocytogenes decreased to below the detectable level in a 1-mL sample within 24 h of storage at 7°C in lben fermented with the Bac+ starter culture. On the contrary, L. monocytogenes survived for 6 days of storage at 7°C in lben made with the Bac- starter. The Bac+ wild strain of the starter studied could be adequately used to produce lben or similar indigenous fermented milks of improved hygienic quality on an industrial scale. Alternatively, it could be used as an adjunct in minimally processed products or in products obtained from raw milk to add a safety factor

Policy diffusion and transfer of the Bologna Process in Africa’s national, sub-regional and regional contexts

This article traces the process of diffusion and transfer of the European Bologna Process reforms in Africa's national, sub-regional and regional contexts and examines factors that drive these processes. Considering that African countries are not official signatories but are aligning their systems of education to the BP, and in the absence of a coordinated effort and the use of digital technology to produce and present data that documents and maps out progress, tracing the diffusion process in this context is challenging, which is the reason for limited research in this area. Based on a review of existing literature, this article argues that in Africa, the dissemination and transfer of BP-related reforms started as individual projects by national governments as early as 2000 before metamorphosing into sub-regional and regional initiatives. The article identifies economic, political and discursive factors as well as the selective and silent processes that shaped Bologna transfer at these different levels in Africa