Phoenix dactylifera L.seed protein hydrolysates as a potential source of peptides with antidiabetic and anti-hypercholesterolemic properties:An in vitro study

This study aimed to explore the effect of enzymatic hydrolysis conditions(enzyme types and hydrolysis time)of date seed protein hydrolysates(DSPH)on in-vitro inhibition of molecular markers related with diabetic and hypercholesteremia.The DSPH was prepared using alcalase,bromelain,papain,and protease at different hydrolysis time(HT)(2,4 and 6 h).Higher degree of hydrolysis was observed for papain at 6 h HT.The results showed that alcalase and bromelain generated DSPHs at 6 h HT greatly improved the pancreatic lipase inhibition activity while the cholesterol esterase inhibition activity was greatly enhanced with alcalase and protease at 6 h HT and papain generated DSPHs at 4 h HT.Bromelain generated DSPH displayed the highest inhibition of dipeptidyl peptidase-IV(DPP-IV)and amylase at 6 and 2 h hydrolysis time,respectively.All the enzymes at 2 h HT except that of papain showed the highestα-glucosidase inhibitory activities.These results revealed that the DSPH displayed enhanced inhibitory activities towards molecular markers related with diabetes and obesity and thus have promising potential to be used as health-promoting ingredients in the fabrication of functional foods.

Production and utilization of non-covalent dairy-based proteins complexed with date palm leave polyphenols for improving curcumin stability

This study provides insights into the non-covalent complexation of greent solvent extracted date leaf polyphenolic extracts(DLPE)with bovine and camel dairy proteins and their utilization for enhancing the photo and thermal stabilities of curcumin loaded into nano-emulsion.UV-Vis and fluorescence spectroscopies showed marked variation among bovine and camel dairy-DLPE complexes.Dairy protein-DLPE complexation improved the radical scavenging activities compared to unmodified milk proteins.Caseins-DLPE complexes showed higher total phenolic content(TPC)than whey-DLPE complexes with camel casein(CC)showing highest values.The formation of protein-polyphenol complexes was also predicted using molecular docking that suggested van der Waals interaction as a dominant force binding camel dairy protein with DLPE.Further,curcumin-loaded nanoemulsions were fabricated using dairy proteins-DLPE complexes as emulsifiers.The thermal stability of curcumin loaded in nanoemulsions was studied at different temperatures(55℃,75℃ and 95℃)for varying periods of time(0-6 h)while photostability was studied by exposure to UV light for a period of 120 min.The results showed that the thermal and photostability of curcumin improved when dairy protein-DLPE complexes were used for nanoemulsion production.Camel casein-DLPE stabilized nanoemulsions imparted the highest thermal and photostabilities to curcumin while camel whey-DLPE showed the lowest retention of curcumin in nanoemulsions.In vitro digestion showed complexation of caseins with DLPE improved the bioaccesibility of curcumin.Moreover,curcumin bioaccesibility was higher for CC-DLPE(69.25%)compared to CC(49.83%)stabilized emulsions.Overall,CC-DLPE complexes demonstrated the superior performance for stabilizing the emulsion and delivering the curcumin in simulated GI tract efficiently.