Optimisation and Characterisation of the Protein Hydrolysate of Scallops (Argopecten purpuratus) Visceral By-Products.

In this research, scallops (Argopecten purpuratus) visceral meal (SVM) and defatted meal (SVMD) were analysed for their proximal composition, protein solubility, and amino acid profile. Hydrolysed proteins isolated from the scallop's viscera (SPH) were optimised and characterised using response surface methodology with a Box-Behnken design. The effects of three independent variables were examined: temperature (30-70 °C), time (40-80 min), and enzyme concentration (0.1-0.5 AU/g protein) on the degree of hydrolysis (DH %) as a response variable. The optimised protein hydrolysates were analysed for their proximal composition, yield, DH %, protein solubility, amino acid composition, and molecular profile. This research showed that defatted and isolation protein stages are not necessaries to obtain the hydrolysate protein. The conditions of the optimization process were 57 °C, 62 min and 0.38 AU/g protein. The amino acid composition showed a balanced profile since it conforms to the Food and Agriculture Organisation/World Health Organisation recommendations for healthy nutrition. The predominant amino acids were aspartic acid + asparagine, glutamic acid + Glutamate, Glycine, and Arginine. The protein hydrolysates' yield and DH % were higher than 90% and close to 20%, respectively, with molecular weight between 1-5 kDa. The results indicate that the protein hydrolysates of scallops (Argopecten purpuratus) visceral by product optimised and characterised was suitable a lab-scale. Further research is necessary to study the bioactivity properties with biologic activity of these hydrolysates.

Dietary Fatty Acids in Postprandial Triglyceride-Rich Lipoproteins Modulate Human Monocyte-Derived Dendritic Cell Maturation and Activation.

Dietary fatty acids have been demonstrated to modulate systemic inflammation and induce the postprandial inflammatory response of circulating immune cells. We hypothesized that postprandial triglyceride-rich lipoproteins (TRLs) may have acute effects on immunometabolic homeostasis by modulating dendritic cells (DCs), sentinels of the immunity that link innate and adaptive immune systems. In healthy volunteers, saturated fatty acid (SFA)-enriched meal raised serum levels of granulocyte/macrophage colony-stimulating factor GM-CSF (SFAs > monounsaturated fatty acids (MUFAs) = polyunsaturated fatty acids (PUFAs)) in the postprandial period. Autologous TRL-SFAs upregulated the gene expression of DC maturation (CD123 and CCR7) and DC pro-inflammatory activation (CD80 and CD86) genes while downregulating tolerogenic genes (PD-L1 and PD-L2) in human monocyte-derived DCs (moDCs). These effects were reversed with oleic acid-enriched TRLs. Moreover, postprandial SFAs raised IL-12p70 levels, while TRL-MUFAs and TRL-PUFAs increased IL-10 levels in serum of healthy volunteers and in the medium of TRL-treated moDCs. In conclusion, postprandial TRLs are metabolic entities with DC-related tolerogenic activity, and this function is linked to the type of dietary fat in the meal. This study shows that the intake of meals enriched in MUFAs from olive oil, when compared with meals enriched in SFAs, prevents the postprandial production and priming of circulating pro-inflammatory DCs, and promotes tolerogenic response in healthy subjects. However, functional assays with moDCs generated in the presence of different fatty acids and T cells could increase the knowledge of postprandial TRLs' effects on DC differentiation and function.

Evaluation of Anti-Inflammatory and Atheroprotective Properties of Wheat Gluten Protein Hydrolysates in Primary Human Monocytes.

Bioactive protein hydrolysates have been identified in several sources as possible agents in the prevention and treatment of many diseases. A wheat gluten (WG) concentrate was hydrolyzed by Alcalase under specific conditions. The resulting hydrolysates were evaluated by in vitro cell-free experiments leading to the identification of one bioactive WG protein hydrolysate (WGPH), which was used at 50 and 100 µg/mL on primary human monocytes. Reactive oxygen species (ROS) and nitrite levels and RT-qPCR and ELISA techniques were used to analyze the functional activity of WGPH. Our results showed that WGPH hydrolyzed in 45 min (WGPH45A) down-regulated gene expression of Interleukin (IL)-1ß, IL-6, IL-17, and Interferon gamma (IFNγ) and reduced cytokine release in lipopolysaccharide (LPS)-stimulated monocytes. In addition, WGPH45A down-regulated gene-related to atherosclerotic onset. Our results suggest that WGPH45A has a potent anti-inflammatory and atheroprotective properties, reducing the expression of gene-related inflammation and atherosclerosis that could be instrumental in maintaining cardiovascular homeostasis.

Hemp (Cannabis sativa L.) Protein Hydrolysates Promote Anti-Inflammatory Response in Primary Human Monocytes.

Hemp seeds have a wide variety of chemical compounds which present biological activity. Specifically, the focus on proteins and bioactive peptides are increasing as alternative sources of nutraceutical uses. In the literature, hemp protein products (HPPs) have reported antioxidant and anti-inflammatory properties. This study aimed to determine the inflammation-related modulatory effects of HPPs on lipopolysaccharide (LPS)-activated primary human monocytes. CD14+ cells were immunomagnetically isolated from buffy coats and the anti-inflammatory activity of hemp protein isolate (HPI) and hydrolysates (HPHs) was evaluated on LPS-stimulated human primary monocytes. The specific markers of inflammation, polarization, and chemoattraction were measured by RT-qPCR and ELISA assays. Our results showed that HPPs decreased the pro-inflammatory mediators (TNFα, IL-1ß, and IL-6) and increased the anti-inflammatory mediators (IL-10 and IL-4). In addition, M1 polarization marker gene expression (CCR7 and iNOS) was downregulated by HPPs and, M2 polarization marker gene expression (CD200R and MRC1) was upregulated. Finally, the mRNA expression of chemotaxis genes (CCR2 and CCL2) was downregulated by HPPs. In conclusion, this study suggests that HPPs may improve chronic inflammatory states and promote regenerative processes by reprogramming monocytes toward M2 polarization phenotype.

Neuroprotective protein hydrolysates from hemp (Cannabis sativa L.) seeds.

Hemp (Cannabis sativa L.) seeds are well known for their potential use as a source of nutrients, fiber, and bioactive compounds. A hemp protein isolate, prepared from defatted hemp flour, was hydrolyzed by alcalase and flavourzyme under specific conditions. The resulting hydrolysates were evaluated for the selection of potentially bioactive hemp protein hydrolysates (HPHs) owing to their DPPH scavenging and ferric reducing antioxidant power activity. In vitro cell-free experiments led to the identification of two bioactive HPHs, HPH20A and HPH60A + 15AF, which were used at 50 and 100 µg mL-1 on BV-2 microglial cells in order to evaluate the anti-neuroinflammatory activities. Our results showed that HPH20A and HPH60A + 15AF down-regulated TNF-α, IL-1ß, and IL-6 mRNA transcriptional levels in LPS-stimulated BV-2 microglial cells. In addition, HPH20A and HPH60A + 15AF up-regulated the gene expression of anti-inflammatory cytokine IL-10. This study suggests for the first time that HPHs may improve the neuroinflammatory and inflammatory states, supporting the nutraceutical value of hemp seeds.