Evaluation of ACE, α-glucosidase, and lipase inhibitory activities of peptides obtained by in vitro digestion of selected species of edible insects

Abstract

The objective of this study was to examine the inhibition of the activity of enzymes associated with development of the metabolic syndrome by peptide fractions received from simulated gastrointestinal digestion and absorption of heat-treated edible insects. The inhibitory activities of insect-derived peptides were determined against key enzymes relevant to the metabolic syndrome such as the angiotensin-converting enzyme (ACE), pancreatic lipase, and α-glucosidase. After the in vitro absorption process, all hydrolysates showed high inhibitory activity; however, the most effective metabolic syndrome-inhibitory peptides were received after separation on Sephadex G10. The best results were found for peptide fractions obtained from Schistocerca gregaria. The highest enzymes inhibitory activities were obtained for peptide fractions from S. gregaria: boiled for ACE (IC 50 3.95 µg mL −1), baked for lipase (IC 50 9.84 µg mL −1), and raw for α-glucosiadase (IC 50 1.89 µg mL −1) S. gregaria, respectively. Twelve sequences of peptides from the edible insects were identified and their chemical synthesis was carried out as well. Among the synthesized peptides, the KVEGDLK, YETGNGIK, AIGVGAIR, IIAPPER, and FDPFPK sequences of peptides exhibited the highest inhibitory activity. Generally, the heat treatment process applied to edible insects has a positive effect on the properties of the peptide fractions studied.

Nutritional, Physiochemical, and Antioxidative Characteristics of Shortcake Biscuits Enriched with Tenebrio molitor Flour

“…Numerous amino acid sequences from insects have been identified, which have been associated with in vitro bioactive properties [23,26,[40][41][42]. Proteins and peptides are also involved in the antioxidant properties of insects [25,26,43], and depending on the species of edible insects these proteins might change the DPPH • and ABTS •+ radical scavenging activity. Such changes might be depend on the molecular weight of protein or peptide in question, as well as the amino acid composition [44].…”

Current Trends of Bioactive Peptides—New Sources and Therapeutic Effect

“…They allow determination of the influence of diet compounds on enzyme activity, digestibility, bioavailability, release of bioactive compounds, and structural changes in food [ 42 ]. The model used depends on the food matrix and the aim of study [ 43 , 44 , 45 ].…”

“…The ACE-inhibitory peptides identified from protein of B. mori pupae were e.g., KHV [ 126 ], ASL [ 127 ], and GNPWM [ 124 ] ( Table 4 ). Peptides showing this activity were also identified in cricket ( Gryllodes sigillatus ), mealworm ( Tenebrio molitor ), and locust protein ( Schistocerca gregaria ) [ 44 , 128 ]. Peptides inhibiting the activity of other enzymes, e.g., DPP-IV [ 128 ], α-glucosidase [ 44 , 129 ], and lipase [ 44 ], were identified in insect protein as well.…”

“…Peptides showing this activity were also identified in cricket ( Gryllodes sigillatus ), mealworm ( Tenebrio molitor ), and locust protein ( Schistocerca gregaria ) [ 44 , 128 ]. Peptides inhibiting the activity of other enzymes, e.g., DPP-IV [ 128 ], α-glucosidase [ 44 , 129 ], and lipase [ 44 ], were identified in insect protein as well. Generally, insects are a source of bioactive peptides with in vitro inhibitory activity against selected enzymes such as ACE, lipase, and α-glucosidase, which may be involved in the pathogenesis of metabolic syndrome.…”

“…Generally, insects are a source of bioactive peptides with in vitro inhibitory activity against selected enzymes such as ACE, lipase, and α-glucosidase, which may be involved in the pathogenesis of metabolic syndrome. Moreover, the heat treatment of insects has a significant impact on the extraction of bioactive peptides through enzymatic hydrolysis [ 44 ].…”