Laboratoire de Biotechnologie, Environnement et Qualité (LABEQ), Département de Biologie, Faculté des Sciences, Université Ibn Tofaïl, BP 133, 14000 Kénitra, Morocco
Thirty high activity yeast strains saccharolytic and acidifying were isolated from sugar cane press juice and molasses from a sugar plant (grown on a solid semi-synthetic culture medium supplemented with 3 g of sucrose and incubated for 72 h at 40 ° C. the purification of the strains is verified by microscopic control after three subculture cycles in liquid medium and a passage on solid medium in a Petri dish 80 mm in diameter. the identification was carried out according to biochemical tests, physico-chemical and microscopic. These culture, purification and identification have isolated a strain which we named LES16 characterized by its temperature tolerance, which considerably increases during fermentation. This is a Candida sp which presents optimal conditions (pH 5, 3 g / l sucrose, 1 g / l (NH4) 2SO4 and 40 ° C) an enzyme activity of 4228 IU / l. has a major interest in the application of a technique primarily based on the use of a mixed starter containing lactic acid bacteria and yeast fermentation and strong acidifying power. Localization of beta-fructofuranosidase activity LES16 strain was obtained by culture on the semi-synthetic liquid medium supplemented with 3 g of sucrose. The centrifuge technology and cell lysis have produced more cell fractions to search for enzyme activity.