# Fabrication of levan derived from Priestia koreensis HL12 into polyvinyl alcohol and gelatin based composite film for food packaging

## TL;DR

Researchers made edible food packaging films using levan from a bacteria, combining it with gelatin and polyvinyl alcohol to improve performance.

## Contribution

First integration of levan from Priestia koreensis HL12 into PVA/gelatin-based composite films for food packaging.

## Key findings

- PVA/GE/20%LV film showed highest elongation at break (166%) and lowest swelling index.
- SEM and FTIR confirmed successful crosslinking and film morphology.
- 20% levan content provided optimal mechanical and thermal properties for packaging.

## Abstract

This study presents the first report on the integration of levan produced by Priestia koreensis HL12 into PVA/gelatin-based composite films and provides a comprehensive characterization of the resulting edible films. The properties of PVA/gelatin composite films were enhanced by incorporating levan at different ratios (10, 20, 30, 40, and 50 wt% relative to PVA). A small amount of glycerol was added as a plasticizer, and the three components were crosslinked using genipin. The PVA/gelatin/levan composite films were fabricated via the solvent casting method. The fabricated films exhibited smooth surface morphologies and a gradual color transition from blue to violet with increasing levan content. Scanning electron microscopy (SEM) was used to examine film morphology, while Fourier transform infrared spectroscopy (FTIR) confirmed crosslinking interactions between genipin and gelatin in the PVA/gelatin/levan component. Thermogravimetric analysis (TGA) was employed to evaluate thermal stability, and tensile testing was conducted to determine mechanical strength as a function of levan content. Among the formulations, PVA/GE/20%LV film exhibited enhanced thermal stability (from 321 to 314 °C) compared to PVA/GE/0%LV, the highest elongation at break (166%), and the lowest swelling index. These findings highlight the potential of levan from P. koreensis HL12 as a functional biopolymer, with the PVA/GE/20%LV film identified as the most suitable formulation for edible food packaging applications.

Image 1

•Hydrogel based composite was successfully prepared from levan, gelatin and polyvinyl alcohol.•Genipin was chemically employed as a crosslinker agent for composite films formation.•Levan was successfully prepared from Priestia koreensis HL12.•The 20% levan composite film exhibited optimal mechanical and physicochemical properties for packaging applications.

Hydrogel based composite was successfully prepared from levan, gelatin and polyvinyl alcohol.

Genipin was chemically employed as a crosslinker agent for composite films formation.

Levan was successfully prepared from Priestia koreensis HL12.

The 20% levan composite film exhibited optimal mechanical and physicochemical properties for packaging applications.