Bioactivities of Mealworm (Alphitobius diaperinus L.) Larvae Hydrolysates Obtained from Artichoke (Cynara scolymus L.) Proteases

SIMPLE SUMMARY: Edible insects can provide an alternative and sustainable source of dietary protein to meet the future demand of the growing global population. Therefore, this study analysed the impact of mealworm (Alphitobius diaperinus L.) larvae hydrolysis using artichoke (Cynara scolymus L.) flower’s enzyme extract, on the production of peptide hydrolysates with potential bioactivity. The antioxidant capacity against the 1,1,-diphenil-2-picrylhydrazyl (DPPH) radical and the angiotensin-I-converting enzyme inhibitory activity of the hydrolysates were determined. Furthermore, the identification of the peptide sequences was conducted to detect the potential bioactive peptides in the hydrolysates. The results reveal that the water-soluble extract of artichoke flower could be suitable for producing bioactive peptides from mealworm larvae, and could be incorporated as an ingredient in future functional food products. ABSTRACT: In this study, we aimed to obtain hydrolysates with bioactive peptides from mealworm (Alphitobius diaperinus L.) larvae using an artichoke (Cynara scolymus L.) enzyme extract. Two types of substrates were used: the raw larvae flour (LF) and its protein extract (PE). The hydrolysis yield, considering the peptide concentration of the hydrolysates, was higher in PE hydrolysates than in LF hydrolysates (6.39 ± 0.59 vs. 3.02 ± 0.06 mg/mL, respectively). However, LF showed a higher antioxidant activity against the DPPH radical than PE (59.10 ± 1.42 vs. 18.79 ± 0.81 µM Trolox Eq/mg peptides, respectively). Regarding the inhibitory activity of angiotensin-I-converting enzyme (ACE), an IC(50) value of 111.33 ± 21.3 µg peptides/mL was observed in the PE. The identification of the peptide sequence of both hydrolysates was conducted, and LF and its PE presented 404 and 116 peptides, respectively, most with low molecular weight (<3 kDa), high percentage of hydrophobic amino acids, and typical characteristics of well-known antioxidant and ACE-inhibitory peptides. Furthermore, the potential bioactivity of the sequences identified was searched in the BIOPEP database. Considering the antioxidant and ACE-inhibitory activities, LF hydrolysates contained a larger number of sequences with potential bioactivity than PE hydrolysates.