Platelet activation is related to the psychopathology of major depression. We attempted to search and identify protein biomarkers from the platelets of patients with major depression. High resolution two-dimensional Differential Gel Electrophoresis (2D-DIGE), the matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), Western blot, and bioinformatic tools were applied to examine the platelet proteins of 10 patients with major depression and 10 healthy controls.

Slightly acidic electrolysed water (SlAEW) and acidic electrolysed water (AEW) have been demonstrated to effectively inactivate food-borne pathogens. However, the underlying mechanism of inactivation remains unknown. Therefore, in this study, a differential proteomic platform was used to investigate the bactericidal mechanism of SlAEW, AEW, and sodium hypochlorite (NaOCl) solutions against Vibrio parahaemolyticus. The upregulated proteins after SlAEW, AEW, and NaOCl treatments were identified as outer membrane proteins K and U. The downregulated proteins after the SlAEW, AEW, and NaOCl treatments were identified as adenylate kinase, phosphoglycerate kinase, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and enolase, all of which are responsible for energy metabolism. Protein synthesis-associated proteins were downregulated and identified as elongation factor Tu and GAPDH. The inhibitory effects of SlAEW and AEW solutions against V. parahaemolyticus may be attributed to the changes in cell membrane permeability, protein synthesis activity, and adenosine triphosphate (ATP) biosynthesis pathways such as glycolysis and ATP replenishment.

Bioactive peptides (BPs) released by proteases from different food protein sources are often served as antioxidants in food applications. This study aims to investigate 11 BPs derived from fish and egg white as potential natural antioxidants by antioxidant activity assays. The kinetic activity of the BPs against xanthine oxidase (XOD) and tyrosinase was also analyzed. The antioxidative capacity of the BPs indicated that VWWW (VW4, mackerel meat), followed by IRW (IW3, egg white) and VKAGFAWTANQQLS (VS14, tuna backbone protein), possessed the highest antioxidant activity in 1,1-diphenyl-2-picrylhydrazyl radical (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) and reducing power (RP) assays. Both the free-radical scavenging score predicted from the AnOxPePred algorithm and the DPPH, ABTS and RP results indicated that VW4 was the best antioxidant. Furthermore, the XOD and tyrosinase inhibition by three selected peptides exhibited competitive patterns of effective inhibition. The half maximal inhibitory concentrations (IC₅₀) of the peptides for XOD inhibition were 5.310, 3.935, and 1.804 mM for VW4, IW3, and VS14, respectively, and they could serve as competitive natural XOD inhibitors. The IC₅₀ of the peptides for tyrosinase inhibition were 1.254, 2.895, and 0.595 mM for VW4, IW3, and VS14, respectively. Overall, VW4, IW3, and VS14 are potential antioxidants and natural XOD inhibitors for preventing milk-fat oxidation, and anti-browning sources for inhibiting food-derived tyrosinase oxidation.

The aim of this study was to investigate the physicochemical characteristics and volatile flavor of fried tilapia skins under three frying methods. Conventional deep-fat frying usually increases the oil content of the fried fish skin and leads to lipid oxidation, which reduces the product quality. Alternative frying methods, such as air frying for 6 and 12 min under 180 °C (AF6, and AF12) and vacuum frying at 0.085 MPa for 8 and 24 min under 120 °C (VF8, and VF24) were compared to conventional frying for 2 and 8 min under 180 °C (CF2, and CF8) for tilapia skin. Physical properties of fried skin, such as the moisture content, water activity, L* values and breaking force decreased under all frying methods, while the lipid oxidation and a*, b* values increased with the increase in frying time. In general, VF offered higher hardness of product compared to AF which had a lower breaking force. Especially AF12 and CF8 had the lowest breaking force, which indicated higher crispness. For the oil quality inside the product, AF and VF reduced conjugated dienes formation and retarded oxidation compared to CF. The results of the flavor compositions of fish skin measured using gas chromatography mass spectrometry (GC/MS) with solid phase microextraction (SPME) showed that CF obtained higher unpleasant oily odor (nonanal, 2,4-decadienal, etc.), while AF presented greater grilling flavor (pyrazine derivatives). Because fish skin fried by AF only relied on hot air, Maillard reaction derived compounds, such as methylpyrazine, 2,5-dimethylpyrazine, and benzaldehyde were the leading flavors. This made the aroma profiles of AF very different from VF and CF. Among all the approaches, AF and VF developed lower oil content, mild fat oxidation and better flavor attributes, which proves their practical applications for frying tilapia fish skin.