Reciclagem de células de Saccharomyces cerevisae contendo alta atividade de invertase / Recycling of Saccharomyces cerevisae cells containing high invertase activity

RESUMO

Cold acetone treatment of commercial Saccharomyces cerivisiae resulted in a product called Yeast Dehidrated Cells (YDC) wich contained high invertase activity. The enzyme remained bound to yeast cells and showed maximum activity at pH 4,6 and 55§C. Stability during storage at room temperature (+- 25§C) or in freezer (-18C) by 11 months was above 95 per cent. Half-life under optimal temperature and pH conditions was estimated as being 45h. Additions of YDC (500mg/L) to a solution of sucrose (20 per cent) resulted in 100 per cent sugar hydrolysis, after two hours reaction at 55§C. In a concentration of 1000mg/L, it was possible to recycle YDC for 12 times, with 100 per cent hydrolysis of 20 per cent w/v sucrose, what indicates the potential of reutilization of the enzyme in industrial scale