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Edible insects represent a growing sector of the food industry and have a low carbon footprint. Noteworthy, insects can upcycle different leftovers and byproducts into high-quality nutrients. Herein, the larvae of the edible insect Tenebrio molitor (TML) were fed using local milk industry byproducts. Mozzarella whey and whey permeate obtained in cheese production were used to formulate three alternative diets. Both byproducts are rich in sugars, in particular the disaccharide lactose and the monosaccharides glucose and galactose. Two of the three diets did not interfere with biometric data and vitality, while the use of whey permeate alone significantly reduced development. At the end of the trial, the proximate composition of TML was strongly affected, with an increased protein content of up to +7% and a favorable fat composition. The analysis of secondary metabolites revealed the accumulation of different compounds, in particular monounsaturated fatty acids (MUFAs), amino acids, and the disaccharide trehalose, essential for the correct larval development and pupation. In conclusion, the present study demonstrates that milk industry byproducts can be upcycled as feed for TML, maintaining an optimal nutrient composition and favorably increasing the protein content.

In pre-hypertension, moderate control of blood pressure (BP) can be obtained by a nutritional approach. The effects of a diet enriched with defatted larvae of the mealworm Tenebrio molitor (Coleoptera: Tenebrionidae) (TM) endowed with ACE inhibitory activity was studied in both spontaneously hypertensive rats (SHR) and in the age-matched normotensive Wistar Kyoto strain. These were fed for 4 weeks with standard laboratory rodent chow supplemented with or without TM or captopril. In SHR, the TM diet caused a significant reduction in BP, heart rate and coronary perfusion pressure, as well as an increase in red blood cell glutathione/glutathione disulphide ratio. Rat brain slices of SHR were more resistant to oxidative stress and contained lower levels of inflammatory cytokines, while vascular and liver enzyme-activities were not affected. These results suggest that TM can be considered a new functional food that can lower BP in vivo and thus control cardiovascular-associated risk factors such as hypertension.

Protozoa, of the taxon Gregarinasina, are a heterogeneous group of Apicomplexa that includes ~1600 species. They are parasites of a large variety of both marine and terrestrial invertebrates, mainly annelids, arthropods and mollusks. Unlike coccidians and heamosporidians, gregarines have not proven to have a negative effect on human welfare; thus, they have been poorly investigated. This study focuses on the molecular identification and phylogeny of the gregarine species found in the midgut of two insect species that are considered as an alternative source of animal proteins for the human diet: the mealworm Tenebrio molitor, and the super-worm Zophobas atratus (Coleoptera: Tenebrionidae). Gregarine specimens were isolated from the gut of both larval and adult stages of T. molitor specimens, as well as from Z. atratus larvae. The morphological analyses were restricted to the identification of the different parasite morpho-types, likely corresponding either to different life-cycle stages or to alternative gregarine species. The samples were also used for the DNA extraction necessary for their genetic characterization. Finally, the efficiency of different molecular markers (i.e., 18S rDNA gene alone or combined with the Internal Transcribed Spacer 1) was assessed when applied either to gregarine species identification and to phylogenetic inference.