Antioxidant and Anti-Inflammatory Activities of Hydrolysates and Peptide Fractions Obtained by Enzymatic Hydrolysis of Selected Heat-Treated Edible Insects

Abstract

This study investigated the effect of heat treatment of edible insects on antioxidant and anti-inflammatory activities of peptides obtained by in vitro gastrointestinal digestion and absorption process thereof. The antioxidant potential of edible insect hydrolysates was determined as free radical-scavenging activity, ion chelating activity, and reducing power, whereas the anti-inflammatory activity was expressed as lipoxygenase and cyclooxygenase-2 inhibitory activity. The highest antiradical activity against DPPH^• (2,2-diphenyl-1-picrylhydrazyl radical) was noted for a peptide fraction from baked cricket <i>Gryllodes sigillatus</i> hydrolysate (IC₅₀ value 10.9 µg/mL) and that against ABTS^•+ (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical) was the highest for raw mealworm <i>Tenebrio molitor</i> hydrolysate (inhibitory concentration (IC₅₀ value) 5.3 µg/mL). The peptides obtained from boiled locust <i>Schistocerca gregaria</i> hydrolysate showed the highest Fe²⁺ chelation ability (IC₅₀ value 2.57 µg/mL); furthermore, the highest reducing power was observed for raw <i>G. sigillatus</i> hydrolysate (0.771). The peptide fraction from a protein preparation from the locust <i>S. gregaria</i> exhibited the most significant lipoxygenase and cyclooxygenase-2 inhibitory activity (IC₅₀ value 3.13 µg/mL and 5.05 µg/mL, respectively).