A comparative study of the digestion behavior and functionality of protein from chia (Salvia hispanica L.) ingredients and protein fractions

The protein derived from chia (Salvia hispanica L.), recognized for its balanced amino acid profile, presents a promising, healthier, and more environmentally sustainable option for innovation in the plant-based food industry. This study hypothesized that the geographical location of chia seed cultivation and the processing techniques employed might influence protein digestion patterns, which could, in turn, impact the biological functions of the digestion products. To test this hypothesis, the gastrointestinal fate of degummed-defatted flour (DDF), protein concentrate (PC), and isolated albumin (Alb) and globulin (Glo) fractions from chia seeds was evaluated. Additionally, the antioxidant and anti-inflammatory activities of the resulting digesta using in vitro and cellular assays was compared. After gastrointestinal digestion, PCs sourced from Mexico and UK exhibited higher soluble protein levels (7.57% and 6.33%, respectively) and peptide content (24.8% and 27.9%, respectively), with larger molecular sizes compared to DDF, Alb, and Glo. Leu emerged as the predominant amino acid in all chia digesta. Notably, Mexican Alb displayed the highest ORAC and DPPH activities, with values of 572.23µM TE/g dw and 449.64µM TE/g dw, respectively. Concurrently, Mexican PC showed the highest ABTS activity at 759.77µM TE/g dw. In oxidative-stressed RAW264.7 macrophages, British Glo exerted the most significant ROS at 32.32%, whereas Mexican digesta exhibited superior ROS inhibition in Caco-2 cells. Both Mexican and British PCs released smaller peptides ( < 0.6 kDa) that exhibited strong nitric oxide inhibition potential (83.82% and 66.18%, respectively). Similarly, both Mexican and British Alb fractions displayed significant anti-inflammatory potential, with keratinocyte chemoattractant (KC) inhibition rates of 81.66% and 91.18%, respectively. Overall, the Mexican PC and Alb samples showed an enhanced capacity for mitigating oxidative stress and inflammatory responses in vitro. These findings underscore the potential of chia seeds as functional food ingredients, aligning with the preferences of health-conscious consumers for foods offer additional health benefits.