Green Hydrolysis for Proteins Extraction from Black Soldier Fly (BSF) and its Use for Bioplastics Production

Hermetia illucens. also known as Black Soldier Fly (BSF), is an insect of the Diptera order that is currently widespread and cosmopolitan and is often bred in pilot plants. BLS larvae have the great ability to bioconvert unused nutrients left in organic waste into lipids, proteins, and chitin which could be extracted to produce biobased materials for technical applications. In our study, proteins were extracted from defatted BSF larvae using superheated water, as a technique to intensify the protein extraction. Superheated water is a green solvent and it can be used as a replacement for existing solvents. Superheated water is defined as the liquid water under pressure in the range of atmospheric boiling point 100 °C and critical temperature 374 °C. It is highly effective in terms of hydrolysis or dissolution of proteins to get oligopeptides. Further advantages of using superheated water for protein extraction are that the proteins are extracted in water medium only at neutral pH and are sterilized so that they can be used without any further purification [1]. Proteins extracted were mixed with polyvinyl alcohol (PVA) in different proportions to obtain bioplastics. The term bioplastics refers to materials that possess a bio-based origin, i.e., the derivation, at least in part, from renewable resources and/or biodegradability i.e. the ability to degrade in natural environments or under specific industrial conditions. Traditional plastics, such as low-density polyethylene (LDPE), are widely used in agriculture for uses such as mulching or covering greenhouses. Although appreciated for their low cost and good mechanical and optical performance, during the degradation process, they break down into microscopic fragments that remain in the soil, making them impossible to remove. A solution can be found with the development of alternative materials such as bioplastics, designed not only to degrade completely without leaving harmful residues but also to release nutrients that enrich the soil and support crop growth [2].