Amino Acid Composition, Antioxidant, α-Glucosidase and α-Amylase Inhibitory Activities of the Enzymic Polypeptide from Acer truncatum Seed Meal

As a new food raw material, Acer truncatum seed has been used in the production of edible oil. However, the research on the processing residue (seed meal) has not been reported. The Acer truncatum seed meal was hydrolyzed by seven enzymes and the enzymic polypeptides obtained were characterized by thermogravimetric analysis, gel permeation chromatography, fourier transform infrared spectroscopy and zeta pals dynamic light scattering. In addition, the degree of hydrolysis, amino acid composition, antioxidant activity, α-glucosidase inhibition activity and α-amylase inhibition activity of enzymatic polypeptide were evaluated. The results showed that the yields, average molecular weights, average particle sizes and zeta potentials of enzymic polypeptides obtained were 20.5–40.2%, 7.8–13.9 kDa, 288.3–997.5 nm and ( −)1.8 to ( −)36.4 mV, respectively. The bioactivity results showed that the enzymatic polypeptides not only had higher antioxidant activity, but also better α-glucosidase and α-amylase inhibition activities than the raw materials. Among the seven enzymatic polypeptides, the alkaline protease enzymatic polypeptide had the highest content of the eight essential amino acids (20.3%), the largest value of hydrolysis degree (15.4%) and the most significant bioactivity. The study will provide the data support for developing the new application of seed meal from Acer truncatum.