On-line dialysis with HPLC for the automated preparation and analysis of amino acids, sugars and organic acids in grape juice and wines

A reproducible and high throughput technique is described for on-line clean-up and routine analysis of small molecules such as amino acids, sugars and organic acids in grape juice and wines. A fully automated sample processor (ASTED) provides an efficient way of preparing and cleaning-up raw liquid food samples. Following the usual preparation steps like dilution, addition of internal standards, mixing and derivatization, an on-line dialysis procedure is performed before HPLC analysis, to remove macromolecular and microparticulate interferents resulting from complex matrices. Eighteen amino acids, six organic acids, two sugars, ethanol and glycerol have been determined using two methods. Analytical data are provided both for a grape juice and a red wine

Protein hydrolysate from canned sardine and brewing by-products improves TNF-α-induced inflammation in an intestinal–endothelial co-culture cell model

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-alpha-treated and untreated cells. Results: Upon TNF-alpha 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-alpha-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