Hypoglycemic And Hypolipidemic Activity Of Peptides From The Meal Of Plukenetia Volubilis L.

As an imported oil crop,sacha inchi(Plukenetia volubilis L.)is abundant in protein and fatty acids,and the biological activities of its fatty acids has been extensively studied.However,little information is available about the pharmacological activities of sacha inchi protein and peptides.In present study,hypoglycemic and hypolipidemic activity of peptides from meal of sacha inchi meal(SIM)has been investigated and compared,which further expands the medicinal value of sacha inchi.The protein content of crude protein extracted from SIM using Ultrasonic alkali-dissolved acid extraction method was 74.00±0.43%.The degree of hydrolysis,peptide content,hydrophobicity and molecular weight distribution of the hydrolysate s were measured.The results showed SPr and SA1 possessed higher degree of hydrolysis and lower peptide content,the hydrolysates has a certain degree of hydrophobicity The molecular weight of that is mainly distributed within 0-1k D.The antioxidant activities results showed The hydrolysates have a higher scavenging rate for ABTS free radicals,the highest is SAl that ABTS free radicals can be completely eliminated at 5 mg/m L,however,it is difficult to eliminate DPPH free radicals.The hydrolysates showed a weaker inhibitory effect on?-amylase and significantly improves the activity of?-glucosidase.SPr and SA1 showed the strongest on DPP-IV with IC₅₀ values of 1.007 mg/m L and 2.130 mg/m L,respectively.The IC₅₀ values of the four components SPe,SPa,STr and SBr shown the strongest pancreatic lipase inhibitory activity were 34.96,25.40,24.49,22.90 mg/m L,respectively.According to the inhibitory reversibility of DPP-IV and pancrelipase by the hydrolysates of SIM,peptides identified from the hydrolysates and by ultrafiltration-affinity chromatography were screened to acquire potential 10 DPP-IV and 14 pancreatic lipase inhibitory peptides by molecular docking for solid-phase synthesis to verify their activities.The IC₅₀ values of the peptides GF-6,WH-4,AI-9,and FA-9 obtained from the hydrolysates of SIM with better inhibitory activity against DPP-IV were 75.75 m M,128.40 m M,209.50m M and 325.90 m M,respectively.The IC50 values of the peptides AQ-7,AV-9 and LY-6 with better inhibitory activity on DPP-IV screened by ultrafiltration-affinity chromatography were23.43 m M,53.11 m M and 79.92 m M,respectively.The inhibitory types of GF-6,WH-4,AQ-7,AV-9 and LY-6 against DPP-IV are competitive-based mixed-type inhibition,non-competitive-based mixed-type inhibition,non-competitive type,competitive inhibition and competitive inhibition.The interactions beteen of GF-6,AQ-7 and DPP-IV at the two binding sites respectively proceed spontaneously,which is driven by hydrogen bonds,van der Waals forces,hydrophobicity and electrostatic interactions.The IC₅₀ values of the peptides NV-7,WK-5,and WK-8 with better pancreatic lipase inhibitory activity selected from the hydrolysatea of SIM were 34.01 m M,246.50 m M,52.79 m M,respectively.The IC50 values of the peptides EY-8 and FK-9,which have the strongest inhibitory activity against pancreatic lipase,identified by ultrafiltration-affinity chromatography were 171.00 m M and 55.13 m M,respectively.The types of pancreatic lipase inhibited by NV-7,WK-5,WK-8,EY-8 and FK-9are competitive-based mixed inhibition,non-competitive-based mixed inhibition,non-competitive inhibition,competitive-based mixed inhibition and competitive inhibition,respectively.The spontaneous reaction of mutual binding at two binding sites is driven by enthalpy change between NV-7 and pancreatic lipase whose interaction forces were mainly involved in Hydrogen bond and van der Waals force.Hydrophobic and electrostatic interactions are the main driving forces for the binding of FK-9 to pancreatic lipase at the only binding site.The hydrolysates of SIM can significantly stimulated glucose consumption of IR-Hep G2,in which SPa,STr and SPr can effectively reduce the accumulation of lipid and TG content in Hep G2 cells induced by oleic acid.peptides GF-6,AQ-7,NV-7 and FK-9 exhibited worse efficacy on IR-Hep G2 glucose consumption,however,which showed potent Inhibition oleic-acid-induced the accumulation of lipid,intracellular TG and ROS level in Hep G2 cells.