Divinyl sulfone (DVS) has been used to activate agarose beads. The DVS activated agarose resulted quite stable in the pH range 5-10 at 25 °C under wet conditions, and can react rapidly with α-amides ...of Cys and His, at pH 5-10, with Lys mainly at pH 10 and with Tyr in a much slower fashion. After blocking with different nucleophiles, the support lost all reactivity, confirming that this protocol could be useful as an enzyme-support reaction end point. Then, chymotrypsin was immobilized on this support at pH 5, 7 and 10. Even though the enzyme was immobilized at all pH values, the immobilization rate decreased with the pH value. The effect of the immobilization on the activity depended on the immobilization pH, at pH 7 the activity decreased (to 50%) more than at pH 10 (by a 25%), while at pH 5 the immobilization has no effect. Then, the effect of blocking with different reagents was analyzed. It was found that blocking with ethylenediamine improved the enzyme activity by 70% and gave the best stability. The stability of all enzyme preparations improved when 24 h incubation was performed at pH 10, but the qualitative stabilization depended on the inactivation conditions. The analysis of the amino acids of the preparation immobilized at pH 10 showed that Lys, Tyr and Cys residues were involved in the immobilization, involving a minimum of 10 residues (glyoxyl agarose gave 4 Lys involved in the immobilization). The new preparation was 4-5 fold more stable than glyoxyl agarose preparation, considered a very stable one, and in some instances was more active than the free enzyme (170% for the enzyme immobilized at pH 10). Thus, DVS activated supports are very promising to permit the multipoint covalent attachment of enzymes, and that way to improve their stability.
DVS supports are very suitable to stabilize enzymes
via
multipoint covalent attachment.
Chia seeds and chia flour could be used as ingredients to enrich foods owing to their high amount of nutrients. The goal of this investigation was to provide further information about how replacing ...wheat flour with chia ingredients (seeds, whole flour, semi-defatted, and low-fat flours) affects the nutritional and functional value of bread. The higher levels of proteins, lipids and minerals determined in raw chia flours directly affected the increase of these nutrients. High levels of phytates were found in chia ingredients (5.1-6.6 μmol/g d.b.), which affect Zn and Fe bioavailability, as predicted by phytate/mineral molar ratios. Bread with chia had a high amount of linoleic acid, especially in bread with chia seeds, owing to protection of seed integrity during baking. Chia ingredients did not show limiting essential amino acids such as lysine, which is deficient in cereals. Glycemic index was lower in bread with chia ingredients compared to control. The beneficial effects on glucose metabolism together with the nutritional and functional characteristics could be clinically important for prevention of metabolic diseases.
The use of quinoa could be a strategy for the nutritional improvement of bakery products. The inclusion of this pseudocereal, with its suitable balance of carbohydrates, proteins, lipids and ...minerals, could contribute to attaining the adequate intake values proposed by the FAO (Food and Agriculture Organization) and/or EFSA (European Food Safety Authority) for suitable maintenance and improvement of the population's health. Bakery products made with white, red or black royal quinoa significantly improved the contribution to an adequate intake of polyunsaturated fatty acids (linoleic and linolenic acids) and dietary fibre, which produced an improvement in the soluble/insoluble fibre ratio. There was also an increase in the contribution to the average requirement of Fe and Zn, although the increase in the phytate/mineral ratio would make absorption of them more difficult. Inclusion of flour obtained from the three quinoas studied slightly improved the protein quality of the products that were prepared and positively affected the reduction in their glycaemic index.
Enzyme immobilization by multipoint covalent attachment on supports activated with aliphatic aldehyde groups (e.g., glyoxyl agarose) has proven to be an excellent immobilization technique for enzyme ...stabilization. Borohydride reduction of immobilized enzymes is necessary to convert enzyme–support linkages into stable secondary amino groups and to convert the remaining aldehyde groups on the support into hydroxy groups. However, the use of borohydride can adversely affect the structure–activity of some immobilized enzymes. For this reason, 2-picoline borane is proposed here as an alternative milder reducing agent, especially, for those enzymes sensitive to borohydride reduction. The immobilization-stabilization parameters of five enzymes from different sources and nature (from monomeric to multimeric enzymes) were compared with those obtained by conventional methodology. The most interesting results were obtained for bacterial (R)-mandelate dehydrogenase (ManDH). Immobilized ManDH reduced with borohydride almost completely lost its catalytic activity (1.5% of expressed activity). In contrast, using 2-picoline borane and blocking the remaining aldehyde groups on the support with glycine allowed for a conjugate with a significant activity of 19.5%. This improved biocatalyst was 357-fold more stable than the soluble enzyme at 50 °C and pH 7. The results show that this alternative methodology can lead to more stable and active biocatalysts.
In this research, scallops (
) 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 (
) 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.
In this work, it has been evaluated how the performance of an electrolyzer, used to treat a clopyralid waste and directly powered without regulation by a battery, is influenced by the electrodes ...resistance. Electrolyzers were equipped with electrodes consisting of the same boron‐doped diamond (BDD) coating deposited on different substrate (Si, Ta and Nb). The results expose great differences despite using the same coating. Faster removal rates were attained with Ta‐ and Nb‐BDD electrodes. The amount of energy required to attain the same removal efficiency showed great differences. Up to 1.95 mg/Wh of pesticide were removed when using Si, compared to 2.14 mg/Wh removed with Ta. Furthermore, the quantity and strength of the generated oxidants were also quite different. 86.78 mmol of oxidants were needed to remove a gram of pesticide with Ta‐BDD and 30.57 mmol with Si‐BDD. Therefore, the electrode resistance is an important aspect that must be considered in order to get a suitable design of energy storage systems that allow the green photovoltaic powering of electrochemical technologies using conventional batteries as a booster to ensure a continuous operation.
Removal company: Conductive diamond electro‐oxidation (CDEO) treatments powered by a fully charged battery and equipped with boron‐doped diamond (BDD) electrodes supported on different substrates showed different performances. The Si‐BDD electrolyzer showed a higher resistance and higher overpotential. Despite the excellent efficiency showed by the Si‐BDD electrodes, the CDEO reactor assembled with Ta‐BDD electrodes exposed the highest removal per unit of energy.
Very rigid supports are useful for enzyme immobilization to design continuous flow reactors and/or to work in non-conventional media. Among them, epoxy-methacrylic supports are easily functionalized ...with glyoxyl groups, which makes them ideal candidates for enzyme stabilization via multipoint covalent immobilization. However, these supports present highly hydrophobic surfaces, which might promote very undesirable effects on enzyme activity and/or stability. The hydrophilization of the support surface after multipoint enzyme immobilization is proposed here as an alternative to reduce these undesirable effects. The remaining aldehyde groups on the support are modified with aminated hydrophilic small molecules (glycine, lysine or aspartic acid) in the presence of 2-picoline borane. The penicillin G acylase from Escherichia coli (PGA) and alcohol dehydrogenase from Thermus thermophilus HB27 (ADH2) were immobilized on glyoxyl-functionalized agarose, Relizyme and Relisorb. Despite the similar density of aldehyde groups displayed by functionalized supports, their stabilization effects on immobilized enzymes were quite different: up to 300-fold lower by hydrophobic supports than by highly hydrophilic glyoxyl-agarose. A dramatic increase in the protein stabilities was shown when a hydrophilization treatment of the hydrophobic support surface was done. The PGA immobilized on the glyoxyl-Relisorb hydrophilized with aspartic acid becomes 280-fold more stable than without any treatment, and it is even more stable than the PGA immobilized on the glyoxyl agarose.
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•GPETAFLR reduced TRAP activity and the expression of osteoclast marker genes.•GPETAFLR increased the release of anti-osteoclastogenic cytokines (IL-4 and IL-10).•Lupinus ...angustifolius L. may prevent osteoclast-related diseases.
The effect of GPETAFLR, a peptide isolated from Lupinus angustifolius L. protein hydrolysate (LPH), on osteoclastogenesis was investigated. Human osteoclasts generated from monocytes were used to analyse the effects of GPETAFLR (50–100 µg/mL) on osteoclastogenesis using TRAP reaction, RT-qPCR, and ELISA procedures. LPS enhanced TRAP activity and the expression of osteoclast marker genes (TRAP, OSCAR, RANK, and CATHK) while downregulated the expression of OPG gene in human monocyte-derived osteoclasts. These effects were reduced with GPETAFLR. Moreover, LPS increased the release of osteoclastogenic cytokines (TNF-α, IL-1β, and IL-6) meanwhile GPETAFLR increased the release of anti-osteoclastogenic cytokines (IL-4 and IL-10) in the medium of human monocyte-derived osteoclasts. For the first time, we show that plant peptides from lupine protein hydrolysates have anti-osteoclastogenic activity. These exciting findings open opportunities for developing nutritional strategies with Lupinus angustifolius L. as dietary source of plant proteins, notably GPETAFLR, to prevent development and progression of osteoclast-related diseases.
L. (Palmariaceae), commonly known as "dulse", is a red alga that grows on the northern coasts of the Atlantic and Pacific oceans, and is widely used as source of fiber and protein. Dulse is reported ...to contain anti-inflammatory and antioxidant compounds, albeit no study has investigated these effects in primary human neutrophils. Implication strategies to diminish neutrophil activation have the potential to prevent pathological states. We evaluated the ability of a phenolic dulse extract (DULEXT) to modulate the lipopolysaccharide (LPS)-mediated activation of primary human neutrophils. Intracellular reactive oxygen species (ROS) were measured by fluorescence analysis and nitric oxide (NO) production using the Griess reaction. Inflammatory enzymes and cytokines were detected by ELISA and RT-qPCR. The results show that DULEXT diminished the neutrophil activation related to the down-regulation of TLR4 mRNA expression, deceased gene expression and the LPS-induced release of the chemoattractant mediator IL-8 and the pro-inflammatory cytokines IL-1β, IL-6 and TNF-α. ROS, NO, and myeloperoxidase (MPO) were also depressed. The data indicated that DULEXT has the potential to disrupt the activation of human primary neutrophils and the derived inflammatory and prooxidant conditions, and suggest a new role for
L. in the regulation of the pathogenesis of health disorders in which neutrophils play a key role, including atherosclerosis.
Seeds from non-drug varieties of hemp (Cannabis sativa L.) have been used for traditional medicine, food, and fiber production. Our study shows that phytol obtained from hemp seed oil (HSO) exerts ...anti-inflammatory activity in human monocyte-macrophages. Fresh human monocytes and human macrophages derived from circulating monocytes were used to evaluate both plasticity and anti-inflammatory effects of phytol from HSO at 10–100 mM using FACS analysis, ELISA, and RT-qPCR methods. The quantitative study of the acyclic alcohol fraction isolated from HSO shows that phytol is the most abundant component (167.59 ± 1.81 mg/Kg of HSO). Phytol was able to skew monocyte-macrophage plasticity toward the anti-inflammatory non-classical CD14+CD16++ monocyte phenotype and toward macrophage M2 (CD200Rhigh and MRC-1high), as well as to reduce the production of IL-1β, IL-6, and TNF-α, diminishing the inflammatory competence of mature human macrophages after lipopolysaccharide (LPS) treatment. These findings point out for the first time the reprogramming and anti-inflammatory activity of phytol in human monocyte-macrophages. In addition, our study may help to understand the mechanisms by which phytol from HSO contributes to the constant and progressive plasticity of the human monocyte-macrophage linage.
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