Pancreatic lipase-inhibiting protein hydrolysate and peptides from seabuckthorn seed meal: Preparation optimization and inhibitory mechanism

摘要

Cost-effective natural lipase inhibitors as anti-obesity agents are highly demanded nowadays. This study demonstrated for the first time to produce porcine pancreatic lipase (PPL) inhibitory peptides from low-cost seabuckthorn seed meal by using response surface analysis. Results showed that the optimal conditions for the preparation of seabuckthorn seed protein hydrolysate (SSPH) by alcalase were: initial pH 10, temperature 50 degrees C, enzyme dosage 0.25 g/100 g protein and 8h of hydrolysis time. Under these conditions, SSPH inhibited PPL activity by similar to 35% in a non-competitive manner. Moreover, SSPH exhibited high thermal stability and insignificant difference (p < 0.05) on PPL inhibitory rate after in vitro gastrointestinal digestion. HPLC-MS/MS analysis revealed 22 arginine-containing peptides in SSPH, and six peptides (Glu-Glu-Ala-Ala-Ser-Leu-Arg, Phe-Arg, Arg-Asp-Arg, Ala-Pro-Tyr-Arg, Val-Arg, Asn-Leu-Leu-His-Arg) were predicted via molecular docking as anti-obesity peptides. The PPL-inhibiting actions of these peptides involved hydrophilic and hydrophobic interactions, hydrogen bonding, 7C-7C stacking and Van der Waals interactions. These interactive forces stabilized the peptidePPL complex while affecting PPL conformational change for accommodating the substrate.

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