Lignin from bamboo shoot shells as an activator and novel immobilizing support for α-amylase

- Bamboo shoot shell (BSS) lignin is an activator to α-amylase.
- α-Amylase was immobilized on BSS lignin via adsorption.
- Immobilization enhanced α-amylase catalytic activity and storage stability.
- Immobilization did not change α-amylase working temperature and pH.
- Immobilized enzyme owned good reusability.

This study examined the feasibility of α-amylase activation and immobilization, using lignin from bamboo shoot shells (BSS). Our results demonstrated that BSS lignin is an excellent α-amylase activator and it elevated α-amylase activity more than two-fold at a concentration of 5 mg/ml. For immobilization of α-amylase via adsorption, BSS lignin was incubated in an α-amylase solution (5 mg/ml) for 20 min, and the maximum specific activity, amount of loaded protein and activity recovery were 92.4 U/mg, 19.0 mg/g and 111%, respectively. In contrast to its free counterpart, immobilized α-amylase improved the catalytic efficiency and storage stability, under comparable working conditions (temperature and pH). Regarding its convenient usage, immobilized enzyme can be suspended in advance, but a suspension incubated at 60 °C should be used within 30 min. The residual activity after 14 re-uses remained at a reasonable level (53.2%). In conclusion, this study reveals a novel support for enzyme immobilization.