Characterization, antioxidant activity, and inhibitory effect on pancreatic lipase of extracts from the edible insects Acheta domesticus and Tenebrio molitor

Abstract

Extracts from the edible insects Acheta domesticus and Tenebrio molitor were obtained by ultrasound-assisted extraction (UAE) and pressurized-liquid extraction (PLE) using ethanol (E) or ethanol:water (E:W). Characterization by GC-MS was performed and total phenolic compounds (TPC), antioxidant activity (DPPH) and pancreatic lipase inhibitory capacity were assayed. Most extracts, mainly ethanolic extracts, predominantly presented lipids as free fatty acids, followed by aminoacids, organic acids, carbohydrates, hydrocarbons and sterols. The UAE-E:W extracts were different, being characterized by organic acids for A. domesticus, or aminoacids for T. molitor. All the extracts exhibited antioxidant activity, which correlated with TPC values, being the E:W extracts the most effective. All the extracts showed inhibitory activity of lipase, although those from T. molitor and extracted by PLE were the most effective. Therefore, bioactive insect extracts can be selectively obtained by advanced methods of extraction, being aqueous ethanol preferred for antioxidant activity and PLE for inhibitory lipase activity.

Keywords: Acheta dometicus; Antioxidant; Bioactive compounds; Edible insects; Pancreatic lipase; Pressurized-liquid extraction; Tenebrio molitor; Ultrasound-assisted extraction.