Covalent Immobilization of Lipase on Bacterial Cellulose Membrane and Nanocellulose

Juliano Brisola,Cesar Augusto Tischer,Renato Marcio Ribeiro Viana,Sabrina Alves De Oliveira,Paula Cristina De Sousa Faria Tischer,Gabriel Jonathan Sousa Andrade

doi:10.1590/1980-5373-mr-2021-0350

Abstract

The cellulose from Komagataeibacter hansenii is synthesized as a thin film at the surface of glucose based media. Strong acid hydrolysis release sections of crystalline cellulose chains in nanometric scale that leads to persistent suspensions in water. The cellulose anhydro-glucose hydroxyls are suitable to receive functional groups as enzymes, and lipases have great economic value being a valuable model for protein immobilization. In this work both, the membrane of bacterial cellulose as well the nanocellulose produced trough acid hydrolysis, was functionalized with a lipase. The bacterial cellulose membranes were produced by Hestrin-Schramm medium, and nanocelluloses produced from the pristine material was characterized using techniques as 13C solid state NMR and transmission electron microscopy (TEM). The pristine membranes and nanocellulose were functionalized with succinic acid as linker, then lipase was conjugated using EDC (N-(3-Dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride), and NHS (N-Hydroxysuccinimide). The effectiveness of the chemical process was characterized, and the lipase activity were measured. The presence of the succinic acid and amide linkage, as well physical-chemical changes on the functionalized polysaccharide. Hence, we inferred that after immobilization the enzyme maintained its activity in both cellulose and the cellulose membrane.

Highlights

The anhydrous-glucose is the representative monomer for the linear cellulose chain, is constituted of two β-(1→4) linked glucose molecules, each rotated 180o relative to the neighboring molecule[1,2]
Cellulose polysaccharide is synthetized on cell membrane, packs on crystalline domains surrounded by paracrystalline chains and interleaved by amorphous regions
On comparing the FTIR data between native cellulose membrane (BC) and cellulose membrane functionalized with succinic acid (BC-s) (Figure 1A), we observed the appearance of the band at 1727 cm-1 on the succinylated membrane, for the C=O bond[30]

Summary

Introduction

The anhydrous-glucose is the representative monomer for the linear cellulose chain, is constituted of two β-(1→4) linked glucose molecules, each rotated 180o relative to the neighboring molecule[1,2]. The isolated ordered cellulose, formerly called cellulose whiskers, nowadays nanocellulose, or CNC,can be obtained on laboratory using sulfuric acid (30% to 60%) at mild temperature (45 ̊C), a process that hydrolysates the amorphous regions, leaving high ordered fibers that are resistant to the acidic attack due to their high structural organization. These structures presents 2 to 20 nm in diameter and range from 100 to 500 nm length, leading to an aspect ratio that varies according to the source of[5,6,7,8,9,10]

Methods

Results

Conclusion