Multi-response optimization of cellulase-assisted hydrolysis for enhanced protein solubilization and bioactive compound release in defatted black sesame meal

Abstract

In this study, a byproduct of oil extraction, defatted black sesame meal, was utilized to obtain proteins and bioactive compounds using enzyme-assisted extraction. The study investigated the influence of three key factors (Enzyme concentration, temperature, and hydrolysis time). The response surface methodology was used to optimize the responses simultaneously. With high R² determination coefficients (0.9483 to 0.9956) and P values of lack-of-fit higher than 0.0005 (0.0785 to 0.5435), the obtained models showed high accuracy and could be used to predict changes in responses. The optimal values for the three investigated variables were found to be 1245 U/kg substrate, 49°C, and 7.25 hours, respectively. The extract obtained then contained 2.23% soluble dry solids, 1.886 g/100 mL soluble protein, 16.14 mg GAE/100 mL total phenolics, and 40.99 mg/100 mL lignans. Antioxidant activity was demonstrated by the IC₅₀ value of DPPH free radical scavenging ability, which was 35.52 mg DW/mL. Simultaneously, through Pearson correlation analysis and principal component analysis, the study proved that this antioxidant activity was mainly contributed to by the phenolics, especially the lignans. The extract obtained from defatted black sesame meal can be used to enhance the nutritional value of food products or, at a higher level, to be processed into functional foods.