Abstract: Feasibility and technology of recovering β-glucosidase from cellobiose hydrolysate by methods of ultrafiltration and acetone precipitation were studied respectively. The 30 ku membrane was selected for recovery of target enzyme when using ultrafiltration technique. From the first batch, β-glucosidase recovery rate and average permeation flux of membrane were 99.6%,118.6 L/(m²·]h), respectively. The amount of recovered β-glucosidase from the 20th batch of cellobiose hydrolysate could still be maintained 90% of initial total enzyme activity, and average permeation flux of membrane reached 79.2 L/(m²·h). When acetone precipitation technique was used for recovery, it was suitable to use acetone and cellobiose hydrolysate at volume ratio from 0.75:1 to 1:1. Temperature and precipitation time had great influence on enzyme recovery rate, which was up to 95.7% when using acetone at -20℃ for 2 h. The 50% enzyme activity could still be maintained from the 15th batch of acetone precipitation, which saved 79% amount of the required enzyme.

Key words: ultrafiltration, acetone precipitation, β-glucosidase, cellobiose hydrolysate