One-pot bioconversion of sucrose to trehalose using enzymatic sequential reactions in combined cross-linked enzyme aggregates.

Amylosucrase (AS), maltooligosyltrehalose synthase (MTS), and maltooligosyltrehalose trehalohydrolase (MTH) were used in combined cross-linked enzyme aggregates (combi-CLEAs) to achieve one-step bioconversion of sucrose to trehalose. Combi-CLEAs of three enzymes were successfully established with acetone and glutaraldehyde (GA) as a precipitant and a cross-linker, respectively. The optimum enzyme ratio was 8:0.5:0.5 (AS, 4mg:MTS, 0.25mg:MTH, 0.25mg). To improve trehalose production, bovine serum albumin was co-aggregated with enzymes as a proteic feeder. The trehalose production yield of combi-CLEAs was about 8% in each cycle on the basis of substrate added up to 400mM. Finally, the combi-CLEAs used in this experiment showed reusability of about five cycles without any activity loss.