Polypeptides from Hermetia illucens: a bio source for innovative materials in the framework of a circular economy model

Plastic waste reduction is one of the main challenges of the 21st century from an environmental and sustainability perspective. Still nowadays, relatively little plastic waste is collected for recycling (less than 10%) and a large fraction (approximately 20%) of Municipal Solid Waste (MSW) goes to landfill. At the global level, the generation of municipal solid waste (MSW) is estimated to be 2.5 billion tonnes per year, of which 30-55% is represented by the so-called organic fraction of municipal solid waste (OFMSW). While the use of alternative, plastic-like materials from natural sources could be one of the most appealing solutions, the massive occupation of agricultural soils for their supply is a big concern. In this scenario, waste valorization is gaining major relevance within the framework of circular economy models, with bio-conversion mediated from insects being one possible and effective answer. The project RICH (Turning Rubbish Into biobased materials: a sustainable CHain for the full valorization of organic waste) aims to develop an innovative and integrated circular economy chain, which, starting from the biotransformation of the organic fraction of municipal solid waste (OFMSW), allows the targeted production of biobased materials with high technological value, such as bioplastics and other advanced protein-based materials. In the present study, proteins and polypeptides were extracted from larvae of Hermetia illucens, also known as black soldier fly. Extracts were characterized by means of proteomics techniques such as BCA, SDSPAGE, and LC-MS analyses. Procedures were next defined to prepare materials such as films, tuning the mechanical properties, and investigating the correlation with the molecular structure. Elastic films were obtained and the elasticity was correlated with the chemical composition and the protocol for film preparation. The results so far obtained pave the way for the application of these materials in the biomedical and packaging fields, bringing us closer to the completion of a new circular economy model.