# Amyloid-Like Self-Assembling of Black Soldier Fly Proteins and Development of Bioplastics

## TL;DR

Black soldier fly proteins can form amyloid-like fibrils used to create biodegradable plastics with good mechanical and barrier properties.

## Contribution

This study demonstrates the amyloid-like self-assembly of black soldier fly proteins into nanofillers for sustainable bioplastic films.

## Key findings

- BSF proteins form amyloid-like fibrils in alkaline conditions, confirmed via ThT fluorescence and TEM.
- Bioplastic films with BSF fibrils show thermal weldability and gas barrier properties comparable to conventional plastics.
- The use of BSF proteins offers a sustainable solution for bioplastic production and organic waste valorization.

## Abstract

The rising demand for sustainable materials has increased
interest
in biodegradable plastics. The black soldier fly (BSF) is a protein
source characterized by the ability to thrive on organic waste, rapid
development, and low environmental impact. This study shows that BSF
proteins can undergo amyloid-like aggregation in alkaline environments,
ultimately leading to amyloid fibrils suitable as reinforcing nanofillers
for bioplastic films. The fibrillization process was monitored through
Thioflavin-T (ThT) fluorescence assay and sodium dodecyl sulfate polyacrylamide
gel electrophoresis (SDS-PAGE). The fibrils’ structure was
studied by means of transmission electron microscopy (TEM) and one-dimensional/two-dimensional
(1D/2D) X-ray diffraction (XRD) analyses performed on films obtained
by casting. Bioplastic films were prepared by blending fibrillizated
BSF proteins with poly­(vinyl alcohol) (PVOH) and glycerol. They exhibited
thermal weldability and mechanical and gas barrier properties in line
with those of the traditional oil- and biobased plastics used for
packaging applications. Due to the current technological interest
in BSF as a bioconverter of organic matter, the BSF protein-based
materials presented in this work not only could help in mitigating
the pressure arising from the accumulation of nonbiodegradable plastics
but also provide tangible evidence about the valorization of municipal
organic waste.