Buffalo worm (Alphitobius diaperinus) proteins: Structural properties, proteomics and nutritional benefits

Biophysical methods such as circular dichroism (CD) and differential scanning calorimetry (DSC) have been minimally used to characterize insect-derived proteins. This study examines the insect Alphitobius diaperinus as a potential protein source. Techniques such as alkaline solubilization coupled to isoelectric precipitation and Osborne fractionation were used to obtain protein concentrates and fractions (albumins, globulins, prolamins, glutelins). SDS-PAGE results showed dominant protein bands at 78.3, 73.3, 49.3, 34.5, 32.0, and 10.3 kDa. All fractions had over 60 % α-helix and β-sheet structures, indicating stable conformations. Prolamins showed high surface hydrophobicity and thermal stability. Nutritionally, glutelins exhibited the highest concentration of essential amino acids (68.75 g/100 g protein), and demonstrated superior In vitro protein-digestibility (84.04 %) as well as the highest In vitro protein-digestibility corrected amino acid score (73.11 %). Therefore, this study characterized the structural-function relationship of A. diaperinus proteins and collectively assessed their suitability and safety for human consumption. [Display omitted] •A. diaperinus Osborne fractions are mainly composed of α-helix, β-sheet and β-turn.•Glutelin-rich protein fraction showed the best protein quality parameters.•Osborne fractionation effectively removes arginine kinase allergen from protein extracts.