Elemental, fatty acid, volatile and amino acid profiles coupled with antidiabetic, antioxidant, and enzyme inhibitory activities of selected edible insects from Uganda

Edible insects are traditionally consumed in Uganda and are increasingly recognized as nutritionally valuable and environmentally sustainable food resources. In this study, the nutritional composition, chemical profiles, biological activities, and safety of three commonly consumed edible insects—Ruspolia differens (green and brown morphs) and Macrotermes nigeriensis—were comprehensively evaluated. Extraction yields differed markedly among species, with R. differens morphs showing substantially higher methanolic yields (46.74–48.93%) than M. nigeriensis (22.57%). Fatty acid analysis revealed oleic acid as the predominant component (42.2–44.1%), followed by palmitic and linoleic acids, indicating a lipid profile rich in mono- and polyunsaturated fatty acids. Volatile profiling demonstrated species-specific aroma signatures, with M. nigeriensis characterized by acetic acid and pyrazines, while R. differens morphs exhibited high levels of isovaleric acid and diverse aromatic compounds. Amino acid analysis showed that methanolic extracts generally contained higher concentrations and broader profiles than aqueous extracts, with taurine, glutamic acid, alanine, and ethanolamine as the dominant components. Elemental analysis by ICP–MS indicated appreciable levels of essential minerals (K, Ca, Fe, Zn, and Se), while potentially toxic elements (As, Cd, Hg, and Pb) were detected at low and variable concentrations depending on species and morph. In enzyme inhibition assays, R. differens methanolic extracts exhibited strong α-glucosidase inhibition (up to 88.16%), comparable to acarbose, whereas α-amylase and cholinesterase inhibition remained limited. Antioxidant activity was moderate, with M. nigeriensis aqueous extract showing the highest DPPH• and ABTS•⁺ scavenging capacities among samples. Antimicrobial activity was generally weak to moderate, with methanolic extracts showing greater efficacy, particularly against Candida albicans. Cytotoxicity and genotoxicity assessments using human dermal fibroblasts and lymphocytes revealed no significant adverse effects at the tested concentrations, with cell viability remaining above 80% and chromosomal aberration indices comparable to negative controls. Overall, the results demonstrate that Ugandan edible insects possess favorable nutritional profiles, selective bioactivities, and an acceptable preliminary safety profile, supporting their potential as alternative food resources. However, controlled rearing, standardized processing, and further studies on bioavailability and long-term consumption are warranted. © The Author(s) 2026.