Faculty of Biotechnology and Food Sciences in Nitra Journal of Microbiology, Biotechnology and Food Sciences 1338-5178 vol. 5 2016 2016-06-01 2016-06-01 AGRO-INDUSTRIAL WASTE BASED GROWTH MEDIA OPTIMIZATION FOR BIOSURFACTANT PRODUCTION BY ANEURINIBACILLUS MIGULANUS 578 583 EN Mohamed Sellami Mohamed Sellami Achref Khlifi Achref Khlifi Fakher Frikha Fakher Frikha Nabil Miled Nabil Miled Lassad Belbahri Lassad Belbahri Faouzi Ben Rebah Faouzi Ben Rebah The present work aimed to optimize a molasses and tuna-processing by-products based new economic medium for biosurfactant (BS) production by a promising strain of Aneurinibacillus migulanus. A culture medium based on a mixture of molasses and supernatants generated from tuna by-products supplemented with oligoelements solution was optimized using the mixture design methodology. Biosurfactant (BS) production and emulsification index (E24) were evaluated. Maximal BS of 2.95 g/l was obtained with a 95:5 (v:v) mixture of molasses and tuna by-product supernatant. However, higher level of E24 (62%) was recorded with medium containing the proportion 5:95 (v:v) of molasses and tuna by-product supernatant. The predicted responses from these mixture proportions were also validated experimentally. Interestingly, oligoelements supplements were not needed to prepare the culture medium. Molasses and tuna-by-product, non-conventional substrates, can be used efficiently for BS production by A. migulanus.