Black Soldier Fly Promoted Bioconversion of Tomato Toxic Plant Biomass to Safe, Functional Animal Feed

The escalating demand for sustainable, nutrient-dense feeds underscores the need to valorize the agro-industrial byproducts utilizing innovative bioconversion strategies. In this context, we have studied the feasibility of incorporating tomato (Solanum lycopersicum) cultivation residues into Black Soldier Fly (BSF) larvae diets to produce high-protein insect meals. These residues are known to contain the naturally occurring toxic steroidal alkaloids tomatidine and α-tomatine, prohibiting their incorporation into human and animal diets. Herein, the tomato cultivation biomass was dried and mill-ground, and its varying volumes were incorporated into standard poultry feed (seven diet levels with 0-100% biomass inclusion) and tested in BSF-larvae-rearing trials to produce insect meals. The optimal results with respect to larvae growth, protein accumulation (highest value = 30.61%), lipid-fiber content, and antioxidant capacity were determined for insect meals obtained from BSF larvae reared with a ration composed of 40% tomato plant biomass. In addition, the toxicity of this insect meal was substantially low, as a consequence of the observed groundbreaking reduction in the contained toxic steroidal alkaloids α-tomatine and its aglycone tomatidine. The results herein reveal the efficacy of the BSF-larvae-rearing process in acting as a biological filter for the bioconversion of the toxic tomato cultivation waste into a functional, safe, and protein-rich livestock feed, supporting the principles of a circular economy.