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Purpose: The anti-inflammatory activity of sardine protein hydrolysates (SPH) obtained by hydrolysis with proteases from brewing yeast surplus was ascertained.Methods: For this purpose, a digested and desalted SPH fraction with molecular weight lower than 10 kDa was investigated using an endothelial cell line (EA.hy926) as such and in a co-culture model with an intestinal cell line (Caco-2). Effects of SPH <10 kDa on nitric oxide (NO) production, reactive oxygen species (ROS) inhibition and secretion of monocyte chemoattractant protein 1 (MCP-1), vascular endothelial growth factor (VEGF), chemokine IL-8 (IL-8) and intercellular adhesion molecule-1 (ICAM-1) were evaluated in TNF-α-treated and untreated cells.Results: Upon TNF-α treatment, levels of NO, MCP-1, VEGF, IL-8, ICAM-1 and endothelial ROS were significantly increased in both mono- and co-culture models. Treatment with SPH <10 kDa (2.0 mg peptides/mL) significantly decreased all the inflammation markers when compared to TNF-α-treated control. This protective effect was more pronounced in the co-culture model, suggesting that SPH <10 kDa Caco-2 cells metabolites produced in the course of intestinal absorption may provide a more relevant protective effect against endothelial dysfunction. Additionally, indirect cross-talk between two cell types was established, suggesting that SPH <10 kDa may also bind to receptors on the Caco-2 cells, thereby triggering a pathway to secrete the pro-inflammatory compounds.Conclusion: Overall, these in vitro screening results, in which intestinal digestion, absorption and endothelial bioactivity are simulated, show the potential of SPH to be used as a functional food with anti-inflammatory properties. [ABSTRACT FROM AUTHOR]

Spent yeast is the second major by-product from brewing. Mechanical disruption of yeast cell wall can be used to obtain β-glucan rich ingredients and separate inner yeast content, both with potential applications as food and nutraceutical ingredients. In this work, the nutritional composition, including minerals and B-complex vitamins, together with the antioxidant activity and phenolic compounds profile of yeast extract, prepared by mechanic disruption of brewer’s spent yeast and removal of yeast cell wall, was investigated. The lyophilised yeast extract presented 64% of proteins with high proportion of essential amino acids and 4% of RNA; macrominerals (Na, K, Ca, Mg), trace elements such as Zn (11.9 mg/100 g dw), Fe (1.76 mg/100 g dw), and Mn (0.564 mg/100 g dw), and vitamins B3 (77.2 mg/100 mg dw), B6 (55.1 mg/100 g dw) and B9 (3.01 mg/100 g dw). Two phenolic compounds were quantified as free forms, gallic acid and (±) catechin, whereas other bounded phenolic compounds were also quantified. The nutrients content, antioxidant properties and phenolic composition of the lyophilised brewer’s spent yeast extract indicates that it can be an interesting food or nutraceutical ingredient. Thus, its recovery will be beneficial in terms of sustainability and environmental impact. [ABSTRACT FROM AUTHOR]