Based on their composition, marine algae, and namely red seaweeds, are good potential functional foods. Intestinal mucosal barrier function refers to the capacity of the intestine to provide adequate containment of luminal microorganisms and molecules. Here, we will first outline the component of seaweeds and will summarize the effects of these on the regulation of mucosal barrier function. Special attention will be paid to unique components of red seaweeds: proteins and derived peptides (e.g., phycobiliproteins, glycoproteins that contain “cellulose binding domains”, phycolectins and the related mycosporine-like amino acids) together with polysaccharides (e.g., floridean starch and sulfated galactans, such as carrageenans, agarans and “dl-hybrid”) and minerals. These compounds have been shown to exert prebiotic effects, to regulate intestinal epithelial cell, macrophage and lymphocyte proliferation and differentiation and to modulate the immune response. Molecular mechanisms of action of peptides and polysaccharides are starting to be elucidated, and evidence indicating the involvement of epidermal growth factor receptor (EGFR), insulin-like growth factor receptor (IGFR), Toll-like receptors (TLR) and signal transduction pathways mediated by protein kinase B (PKB or AKT), nuclear factor-κB (NF-κB) and mitogen activated protein kinases (MAPK) will also be summarized. The need for further research is clear, but in vivo experiments point to an overall antiinflammatory effect of these algae, indicating that they can reinforce membrane barrier function.
1 December 2018 in International Journal of Food Science and Technology
A combination of soaking and extrusion processes of whole rice grain was studied. The effects of temperature (35-55 °C) and time (24-48 h) of soaking treatment on phytic acid (PA), protein and ashes losses using a factorial design were evaluated. Taking into account ash, protein and PA losses, whole rice was soaked 24 h at 45 °C and extruded using a Brabender single screw extruder. Effects of extrusion temperature (160-190 °C) and moisture content (14-19 g/100 g) on product characteristics were evaluated using surface response methodology. Values corresponding to the different responses were: Expansion (1.64-3.28), Specific Volume (5.68-11.06 cm(3)/g), Water absorption (3.41-4.43 mL/g) and Solubility (45.44-66.20 g/100 g). The content of PA was reduced from 740.09 to 163.47 mg/100 g (77%) after both processes, resulting in a higher mineral bio-accessibility, and a 7.3% decrease of protein digestibility. Total soluble phenolics and trolox equivalent antioxidant capacity (TEAC) were affected according to the treatment. Both treatments were important to obtain a nutritionally improved whole grain product.