Affinity screening of potential anti-obesity and anti-diabetic component from pomegranate peel by co-immobilization of lipase and α-amylase using carbon nanotube and hydrogel

Abstract

Lipase and α-amylase play a very important role in the screening of anti-obesity and anti-diabetic drugs. Here, bienzyme microspheres containing lipase and α-amylase were synthesized for simultaneous affinity screening of anti-obesity and anti-diabetic component from pomegranate peel. Lipase was immobilized by functionalized multi-walled carbon nanotube (MWCNT) coated with polyamide dendrimers to obtain MWCNT-lipase. Subsequently, MWCNT-lipase and α-amylase was encapsulated by sodium alginate (SA) hydrogel microspheres to form MWCNT/SA-bienzymes. Under the optimized reaction conditions, the immobilization rate of lipase and α-amylase was 65.16% and 95.79%, and the activities were 85.76% and 88.11% of free enzymes, respectively. Moreover, the enzyme activity conditions of MWCNT/SA-bienzymes were also optimized. The MWCNT/SA-bienzymes were more stable than two free enzymes at room temperature and can be reused. More importantly, in application, a compound (ellagic acid) was selectively screened from pomegranate peel extract by MWCNT/SA-bienzymes. In vitro activity determination confirmed that ellagic acid with IC50 of 369.83 ± 11.75 μg/mL and 672.81 ± 18.55 μg/mL can interact with two enzymes through non-competitive inhibition. The molecular docking showed that ellagic acid bound with α-amylase and lipase through hydrogen bonds, van der Waals forces, etc, resulting in the binding energies of − 8.54 kcal/mol and − 6.87 kcal/mol, respectively.