A novel layered cross-linked enzyme aggregates (CLEAs) of Candida sp. lipase was developed. In the preparation of the novel enzyme aggregates

nano-ZnO particles were modified and cross-linked

which were used as the core of the immobilized lipase

then enzyme molecules were cross-linked on the surface of the nanoparticles

which formed a layered structure. The obtained results showed the bovine serum albumin (BSA) was the suitable agent to modify nano-ZnO particles among the test agents. The other factors affecting the activity of nano layered CLEAs (BSA-N-LCLEAs)

such as ammonium sulfate saturation

concentration of glutaraldehyde

temperature and time for cross-linking reaction

were investigated. The optimum conditions were as follows:ammonium sulfate saturation 58%

glutaraldehyde concentration 3.5%

cross-linking temperature 0℃ and time 2 h. Compared with the traditional CLEAs

the recovered activity of BSA-N-LCLEAs increased about 196.5%. Scanning electron microscopy (SEM) characterization indicated that BSA-N-LCLEAs increased significantly compared to conventional CLEAs. Both pH stability and thermo stability of BSA-N-LCLEAs were improved. Furthermore

the layered CLEAs was used to synthesize astaxanthin succinate. The yields of astaxanthin were about 90%. The immobilized lipase could be reused for five batches

which indicated it had good operational stability.