# Study on the Inhibitory Mechanisms of Native Cellulose, Microcrystalline Cellulose, and Soluble Cellodextrin on α-Amylase and Amyloglucosidase

## TL;DR

This study explores how different forms of cellulose inhibit digestive enzymes, which could help in creating foods that cause less blood sugar spikes.

## Contribution

The study reveals the specific quenching mechanisms and structural effects of cellulose variants on α-amylase and amyloglucosidase.

## Key findings

- SC at 3% reduced fluorescence intensity of α-amylase and amyloglucosidase by over 70% and 40%, respectively.
- SC decreased hydrophobicity around key amino acid residues in α-amylase.
- The findings suggest that structural modulation of cellulose can be used to design low-GI foods.

## Abstract

The inhibitory effects of natural cellulose (NC), microcrystalline cellulose (MC), and soluble fiber dextrin (SC) on amylase activity have been established; however, the underlying mechanisms remain poorly understood. This study employed fluorescence spectroscopy and fluorescence thermodynamics to investigate the quenching parameters, thermodynamic properties, and quenching mechanisms of cellulose interactions with α-amylase and amyloglucosidase. Structural alterations in both enzymes were examined using synchronous fluorescence and UV–visible absorption spectroscopy. The results indicated that NC, MC, and SC primarily induced static quenching of fluorophores in α-amylase and amyloglucosidase. When addition of SC reached 3%, SC reduced the fluorescence intensity of tyrosine and tryptophan residues in α-amylase by 70.9% and 86.8%, and in amyloglucosidase by 43.7% and 46.5%, respectively. Increasing SC levels also decreased hydrophobicity around tyrosine and tryptophan in α-amylase. These findings provide insights into designing cellulose-based amylase inhibitors through structural modulation for developing low-glycemic index (GI) foods.