Assessment of the Physicochemical, Antioxidant, in-vitro Anti-diabetic and Nutritional Characteristics of Pigeon Pea Protein Hydrolysates

Background and Objective: Cajanus cajan (pigeon pea) seeds include special characteristics that can serve as alternative vegan protein sources. The aim of this study was to investigate bioactive peptides in the pigeon pea using economically feasible method of acid and enzymatic hydrolysis. Material and Methods: In this study, pigeon pea was subjected to hydrolysis by two methods of acid and enzymatic hydrolysis. The generated hydrolysates were characterized by result analysis of the protein content and yield, degree of hydrolysis, anti -nutritional profile, Fourier transform infrared spectroscopy, antioxidant assay of 2,2-diphenyl-1-picryl hydrazyl, hydroxyl radical scavenging assay, metal chelating ion assay and reducing power. Moreover, antidiabetic effects were assessed using alpha -amylase inhibition assay . Results and Conclusion: Pigeon pea was digested by acid (pH 4) and enzyme hydrolysis, further subjected to membrane filtration to achieve peptide fractions with bioactive characteristics. The hydrolyzed pigeon pea showed good increased protein contents and degree of hydrolysis, compared with the control. Degree of hydrolysis were 62.7% for acid, 68.42% for enzyme and 34.32% for unhydrolyzed proportion. Hydrolyzed samples included Fourier transform infrared peaks at 3500 - 4000 cm -1 , showing amides I and II. The resulting peptides after the hydrolysis showed a higher range in acid hydrolysis (250 - 20 kDa), whereas the EH fractions showed a very low molecular weight of less than 15 kDa. Peptides produced by AH demonstrated considerable bioactive characteristics, compared to EH antioxidant and anti -diabetic characteristics against the standards. This study highlights production of pigeon pea protein hydrolysates using two methods of traditional (acid) and modern (enzymatic), showing that acid hydrolysate can be a cheap economical method for generating protein hydrolysate with good bioactive characteristics.