RESUMO
New plant proteins with high nutritional quality and biological properties are actively searched worldwide. Moringa oleifera seed protein isolate was prepared from defatted flour and hydrolyzed using four proteases namely trypsin, pepsin, Alcalase, and thermolysin. Then, antioxidant activity and cellular glucose uptake properties of the hydrolysates were assessed. A high degree of hydrolysis was obtained for hydrolysate prepared using trypsin (60.07%), followed by pepsin (57.14%), Alcalase (50.68%), and thermolysin (45.45%). Thermolysin hydrolysate was the most antioxidant efficient (IC50 0.15 and 0.74 mg/mL for 2,2'-azino-bis(acide 3-ethylbenzothiazoline-6-sulfonique) diammonium salt (ABTS) and 2,2-Diphenyl-1-picrylhydrazyl (DPPH) scavenging activity, respectively). Trypsin hydrolysate stimulated high glucose uptake by yeast cells (12.34-35.28%). In the absence of insulin, Alcalase hydrolysate was the most efficient for glucose uptake by the muscle, with the rate ranging from 22.03% to 29.93% after 30 min, then from 29.55% to 34.6% after 60 min. The four hydrolysates improved glucose uptake by the muscle in the presence of insulin with the rate ranging from 46.88% to 58.03% after 30 min, and from 50% to 58.18% after 60 min. Therefore, Moringa oleifera seed proteins could be used to prepare peptides as components of functional foods for the management of type-2 diabetes.
RESUMO
Objective: This work evaluated the antihyperglycemic and antihyperlipidemic activities of pulp extracts of B. toxisperma fruits in rats. Methods: The regulatory ability of the extract on the secretory capacity of pancreatic beta cells (oral glucose tolerance test), and digestion and/or absorption of carbohydrates (starch and sucrose) were evaluated on normal Wistar rats. Diabetes was induced in Wistar rats by intravenous administration of streptozotocin (50 mg/kg), and the animals were treated by the administration of a single daily dose of 400 mg/kg BW of extract. The effect of the extract on blood glucose levels of diabetic rats was monitored 30 min, 2 h, and 5 h after administration, and on the 7th and 14th days of treatment. After 2 weeks of treatment, the rats were sacrificed, liver was preserved for the determination of glycogen content. The serum was prepared and markers for nephro and hepatotoxicity were assessed, as well as cardiovascular risk. Results: The hydroethanolic extract of B. toxisperma fruits significantly reduced glucose concentrations after administration of starch and sucrose in normoglycemic rats by limiting the glycemic peak (increasing of 19.67% vs 27.88% for positive control and 35.96% vs 43.97% for positive control, for starch and sucrose respectively). No effect was observed after glucose administration. B. toxisperma fruits significantly decreased glucose levels by 14.5% and 54.23% respectively 30 min after administration and 7th days of treatment respectively. The extract decreased plasma triglycerides and total cholesterol levels in diabetic rats; it also decreased the cardiovascular risk through the reduction of Cardiac Risk Ratio, Atherogenic Coefficient, and non-High-Density Lipoprotein Cholesterol. The extract also promoted renal function but not structural integrity of the liver. Conclusions: This study suggests that the hydroethanolic pulp extracts of B. toxisperma fruits are good antihyperglycemic and antihyperlipidemic properties agents and could be a potential source of compounds for diabetes management.
