Perspective on integrated biorefinery for valorization of biomass from the edible insect Tenebrio molitor

Background: The edible insect Tenebrio molitor (T. molitor) is a promising food source alternative since it is easily cultivated and its nutritional composition includes high added-value molecules, in particular proteins and lipids. Regarding minerals, iron and zinc contents are higher than chicken, pork, and cow. T. molitor proteins are composed of all the essential amino acids such as valine, leucine, lysine, and also saturated, polyunsaturated, and monosaturated fatty acids. In addition, peptides from T. molitor showed good Angiotensin-converting enzyme (ACE) inhibitory activity, effective in stabilizing blood pressure. Oleic and linoleic acids of T. molitor larvae were analyzed as inhibitors of BACE1 (beta-secretase) for the treatment of Alzheimer's disease. However, T. molitor biomass has been poorly studied and applied in the biorefinery concept, especially exploring green extraction methods, such as ultrasound-assisted, supercritical fluid, pressurized liquid, and microwave-assisted extraction. Scope and approach: This review correlates scientific data and trends between T. molitor and biorefinery approach, and the technologies adopted for the extraction, using unconventional methods, and recovery of products with high added value and their wide application possibilities. Key findings and conclusions: T. molitor biomass is composed of functional proteins with hepatoprotective, antithrombotic, antioxidant properties. It is also a lipid source rich in oleic, linoleic, and palmitic acids. Some biorefinery proposals - sequential extraction eco-friendly processes - are suggested, such as the supercritical fluid extraction for oleic, linoleic, and palmitic acids, followed by protein recovery to bioactive peptide production.