Bioconversion using insects is a promising strategy to convert organic waste (catering leftovers, harvest waste, food processing byproducts, etc.) into biomass that can be used for multiple applications, turned into high added-value products, and address environmental, societal and economic concerns. Due to its ability to feed on a tremendous variety of organic wastes, the black soldier fly (Hermetia illucens) has recently emerged as a promising insect for bioconversion of organic wastes on an industrial scale. A growing number of studies have highlighted the pivotal role of the gut microbiota in the performance and health of this insect species. This review aims to provide a critical overview of current knowledge regarding the functional diversity of the gut microbiota ofH. illucens, highlighting its importance for bioconversion, food safety and the development of new biotechnological tools. After providing an overview of the different strategies that have been used to outline the microbial communities ofH. illucens, we discuss the diversity of these gut microbes and the beneficial services they can provide to their insect host. Emphasis is placed on technical strategies and aspects of host biology that require special attention in the near future of research. We also argue that the singular digestive capabilities and complex gut microbiota ofH. illucensmake this insect species a valuable model for addressing fundamental questions regarding the interactions that insects have evolved with microorganisms. By proposing new avenues of research, this review aims to stimulate research on the microbiota of a promising insect to address the challenges of bioconversion, but also fundamental questions regarding bacterial symbiosis in insects.

Chicken production in Cameroon is steadily increasing, even in regions traditionally dominated by cattle and goat farming. A significant constraint to this growth is the high cost and limited availability of feed, which represents the largest portion of overall production costs. To enhance the sector’s contribution to population well-being, sustainable feed alternatives are essential. Black soldier fly larvae (BSFL, Hermetia illucens) present a promising solution by converting organic waste into nutrient-rich biomass, offering a sustainable method for waste management and producing high-quality proteins, lipids and micronutrients to help mitigate supply shortages of premix (vitamin concentrates) essential for feed formulation. To explore stakeholder acceptance of insect-based feed, a study was conducted in the Vina Division of the Adamawa region in Cameroon, from July to August 2023, involving 107 participants. The survey examined socioeconomic profiles of poultry farmers and poultry feed sellers, and afterwards focused on the acceptance of the use of BSFL as ingredient in poultry feed. Results indicated that poultry farmers were predominantly male, aged between 30 and 40 years. Most poultry farmers had attained a secondary education, while the majority of poultry feed sellers had only completed primary education and lacked formal qualifications in chicken breeding. Consequently, their skills are poor, less than five years of experience. The most important constraints identified were high costs of ingredients needed in the formulation of feed, product marketing difficulties and, disease management. Traditional protein sources like soybean, fishmeal, and groundnut cake were commonly used, but there was notable openness to insect-based feed. Around 76% of poultry farmers and 100% of poultry feed sellers were willing to use BSFL if they were cost-effective and beneficial for poultry health. The acceptance of insect meal indicates a promising future for its use in poultry feed formulations, pending further studies to confirm its efficacy and economic viability.