Hydrolysate protein from brown macroalgae ( Sargassum ilicifolium ): Antioxidant, antitumor, antibacterial, and ACE inhibitory activities

Abstract

The aim of this study was to hydrolysate protein from Sargassum ilicifolium using alcalase and investigate its functional properties. The average molecular weight of hydrolysate protein from S. ilicifolium was estimated to be 4121 Da. Examination of amino acid composition by HPLC showed that this hydrolysate protein mainly contains glutamic acid, aspartic acid, lysine, phenylalanine, and leucine. The antioxidant activity of hydrolysate protein from S. ilicifolium at a concentration of 500 μg/ml for DPPH, ABTS, and FRAP assay were 74.57 ± 0.5%, 91.53 ± 1.58%, and 2.07 ± 0.01 mM, respectively. S. ilicifolium hydrolysate protein also had inhibitory activity against Salmonella typhimurium and Bacillus stearothermophilus. The S. ilicifolium hydrolysate protein had relatively good ACE inhibitory activity (IC50 = 1.28 mg/ml). The 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) assay showed that hydrolysate protein from S. ilicifolium inhibited the growth of carcinoma human lung (A549) cells in vitro with IC50 (the half maximal inhibitory concentration) value of 300.70 mg/ml. Novelty impact statement According to recent studies, high‐quality hydrolysate protein can be proposed as a suitable alternative for animal proteins. In addition to having a significant impact on human health, these compounds also prevent microbial growth and lipid oxidation in foods. Therefore, peptides and protein hydrolysates can be proposed as suitable replacement compounds for synthetic preservatives to increase the shelf life of food products. In this line, in recent years, extensive innovative research has been devoted to obtaining peptides and protein hydrolysates and investigating their bioactive properties.