Compositional changes in preimaginal stages of black soldier fly (Hermetia illucens) reared on fermented water hyacinth with and without supplementation

Water hyacinth (WH) is one of the most rapidly spreading aquatic weeds in Egypt, with negative effects on environment and human beings. Numerous initiatives have been made to eradicate it. Alternatively, Black Soldier Fly (BSF, Hermetia illucens) have emerged as a promising bioconversion agent with the prospect of turning low-cost organic waste into high-value products either through fermentation and/or mixing improves nutrient content and palatability. In the current study, BSFL were reared on substrates generated from a combination of WH (FWH) and control diet (C diet). The BSFL growing diets were C diet, FWH, and a mixture of both C diet and FWH in ratios of 1:1, 1:2, and 1:3, respectively. The present study investigated the effects of water hyacinth on the nutritional composition of BSF preimaginal stages (larvae, prepuae, and pupae) under laboratory conditions. Chemical analyses [protein, carbohydrate, fat, free amino acids, total antioxidant activity, and heavy metals (Cd, Pb, Cu, and Zn)] were conducted on both the substrates and preimaginal stages. The supplementation of FWH with C diet significantly effects on several nutritional parameters of the immature stages. The highest nutritional values of preimaginal stages were generated in both C diet and mixture treatments compared to FWH treatment. Principal components analysis (PCA) revealed correlation between the substrate biochemical parameters and the biochemical components of BSFL. Overall, this study provides baseline knowledge on how BSF rearing could be a solution to managing and upcycling WH in an ecofriendly and economically sustainable way.