Preparation of antibacterial holocellulose nanofibrils from bamboo via surface modification for efficient preservation of wampee.

Abstract

The main challenges in fruit preservation include extending storage duration while maintaining sensory quality and nutritional value. Holocellulose nanofibrils (HCNFs) were prepared in this work by sequential surface modification via sulfation, acetoacetylation, and enamination, coupled with homogenization. The resulting HCNFs were then successfully grafted with gentamicin sulfate groups, which endowed them with long-lasting antibacterial properties for use in wampee (Clausena lansium) preservation. Due to the presence of electrostatic force caused by sulfate half ester, the holocellulose fibers were easily disintegrated into single nanofibrils with an average height and length of about 2.1 nm and 1.1 μm, respectively. The nanofibrils exhibited significant concentration-dependent antibacterial effects against both Gram-negative bacteria (E. coli) and Gram-positive bacteria (S. aureus), with a maximum inhibition rate of 100%. The nanofibrils can effectively inhibit fruit decay, reduce weight loss and firmness decline, maintain the stability of total soluble solids and titratable acidity, and significantly extend the shelf life of the fruits. This work provides a new strategy for developing efficient and biodegradable antibacterial fresh-keeping materials.