HYDROLYSIS OF CONCENTRATED SUCROSE SYRUPS BY INVERTASE IMMOBILIZED ON ANION-EXCHANGER WASTE COTTON THREAD

Yeast invertase was immobilized on polyethyleneimine-coated cotton thread by adsorption followed by crosslinking with glutaraldehyde. The thread-bound invertase was used as an easily retrievable system for the hydrolysis of 80% w/v commercial sucrose syrups. The immobilized enzyme was stable for over 90 days to a temperature of 50°C, only when stored in 80% sucrose solution. Above this temperature, inactivation of enzyme was observed. The cotton threads were used in a batch reactor for hydrolysis of sucrose in about 30 batches carried out over a period of 50 days without loss in activity. The threads could also be used in a packed bed reactor (1.5 l) for 97% hydrolysis of 80% sucrose syrups at 50°C at a rate of about 360 kg per month for a period of 3 months. © 1990.