Metal Ion Chelating Activity Research Articles

PH-Dependent Extraction of Antioxidant Peptides from Red Seaweed Palmaria palmata: A Sequential Approach.

This study employed a diverse approach to extract antioxidant peptides from red seaweed Palmaria palmata, recognized for its comparatively high protein content. Initially, an aqueous extraction of the entire seaweed was performed, followed by enzymatic hydrolysis of the solid residues prepared from the first step. The effects of three different pH levels (3, 6, and 9) during the aqueous extraction were also examined. Results indicated that the solid fraction from the sequential extraction process contained significantly higher levels of proteins and amino acids than other fractions (p < 0.05). Furthermore, the solid fractions (IC50 ranging from 2.29 to 8.15 mg.mL-1) demonstrated significantly greater free radical scavengers than the liquid fractions (IC50 ranging from 9.03 to 10.41 mg.mL-1 or not obtained at the highest concentration tested) at both stages of extraction (p < 0.05). Among the solid fractions, those produced fractions under alkaline conditions were less effective in radical scavenging than the produced fractions under acidic or neutral conditions. The fractions with most effective metal ion chelating activity were the solid fractions from the enzymatic stage, particularly at pH 3 (IC50 = 0.63 ± 0.04 mg.mL-1) and pH 6 (IC50 = 0.89 ± 0.07 mg.mL-1), which were significantly more effective than those from the initial extraction stage (p < 0.05). Despite no significant difference in the total phenolic content between these solid fractions and their corresponding liquid fractions (3.79 ± 0.05 vs. 3.48 ± 0.02 mg.mL-1 at pH 3 and 2.43 ± 0.22 vs. 2.51 ± 0.00 mg.mL-1 at pH 6) (p > 0.05), the observed antioxidant properties may be attributed to bioactive amino acids such as histidine, glutamic acid, aspartic acid, tyrosine, and methionine, either as free amino acids or within proteins and peptides.

In Vitro Antioxidant and Hypocholesterolemic Potency of Melon (Cucumis melo L.) Seed Protein Hydrolysate

Protein hydrolysates have been reported to possess numerous bioactivities. However, research on melon (Cucumis melo L.) seed protein (MSP) hydrolysate is limited. This study aimed to analyze the antioxidant and hypocholesterolemic properties of MSP hydrolysate. Protein from melon seed was obtained by conventional alkaline extraction-isoelectric precipitation method. Enzymatic hydrolysis of MSP was carried out using three different proteases: pepsin, thermolysin, and trypsin, with the enzyme-to-substrate (E/S) ratio of 1:50 (w/w). The results showed that all hydrolysates exhibited antioxidant and hypocholesterolemic activity. The thermolysin-digested hydrolysate had significantly greater (p &lt; 0.05) radical scavenging properties, while trypsin produced the highest (p &lt; 0.05) metal ion chelating activity. At 2 mg/mL, thermolysin-derived MSP hydrolysate showed no significant difference (p &gt; 0.05) in HMGR inhibition activity compared to pravastatin. Additionally, the thermolysin hydrolysate had significantly higher (p &lt; 0.05) bile acid binding ability than other hydrolysates. Overall, the MSP hydrolysate produced by thermolysin exhibited stronger antioxidant and hypocholesterolemic activities when compared to those produced by pepsin and trypsin, suggesting its potential effectiveness in nutraceutical applications.

Phytochemical profile and antioxidant activity of torch ginger (Etlingera elatior) inflorescence extract after in vitro simulated digestion

Background: Torch ginger (Etlingera elatior) is an edible flower whose inflorescence is utlized for culinary purposes to enchance the taste of traditional dishes containing polyphenols and antioxidant compounds. However, investigation on the phytochemical profile and antioxidant activity of torch ginger inflorescence extract following simulated gastrointesinal digestion is still limited. Objective: This study aims to determine the phytochemical profile and evaluate the antioxidant activity of the inflorescence extract after in vitro simulated digestion. Methods: Torch ginger inflorescence (TGI) was extracted by ultrasound-assisted extraction with different solvents (water,50%, and 80% aqueous ethanol). Total phenolics content (TPC), total flavonoid content (TFC), and antioxidant activity were determined by ORAC, DPPH, FRAP, and metal ion (Fe2+) chelating activity. The solvent extraction that gave the highest value of TPC, TFC, and antioxidant activities was used for an in vitro digestion and identification of phytochemicals profile by LC-ESI-QTOF-MS/MS. Furthermore, the TPC, TFC, and antioxidant capacities of digested TGI extract were compared to those of undigested extract. Results: TGI contained 90.24% moisture. The 80% aqueous ethanol extract exhibited the highest antioxidant capacity, with an ORAC value of 1,156.61 ± 11.55 mM TE/g extract, DPPH radical scavenging capacity of 1,087.68 ± 14.37 mM TE/g extract, FRAP value of 799.30 ± 1.45 mM TE/g extract, and Fe2+ chelating capacity of 42.32 ± 3.48% /mg extract. The 39 phytochemicals were identified for 9 flavonoids and 5 phenolic acids. The putative bioactive compounds for antioxidant, anticancer, anti-inflammatory, and anticholesterol were detected in TGIE, such as catechin, 2-hydroxycinnamic acid, astragalin, chlorogenic acid, coumarin, and procyanidin B2. After passing through an in vitro simulated mouth, gastric, and intestinal digestion, the TGI extract exhibited higher values of TPC, TFC, and antioxidative capacities than the undigested extract. Conclusion: This study reviewed the phytochemical components presented in the 80% aqueous ethanol TGIE. The expressed antioxidant capacity was increased when the TGIE passed through the in vitro simulated digestion, which could potentially represent a promising source of endogenous antioxidants in food and nutraceutical applications. Keywords: Antioxidant, edible flower, gastrointestinal digestion, phytochemicals, Torch ginger inflorescence

Biosynthesis of Silver and Gold Nanoparticles Using Geum urbanum L. Rhizome Extracts and Their Biological Efficiency

AbstractThe present study evaluates the biosynthesis of AgNPs and AuNPs using aqueous and ethanolic Geum urbanum L. rhizome extracts. The biosynthesized metal nanoparticles (MNPs) were characterized using UV-Vis spectroscopy, FTIR, DLS, SEM, EDX, and TEM. The UV-Vis spectra confirmed the synthesis of AgNPs and AuNPs through peaks corresponding to the surface plasmon effect of metallic Ag (400–430 nm) and Au (530–570 nm). FTIR analysis indicated that alcohols, phenols, proteins, and carbohydrates from G. urbanum rhizome extracts composition are involved in MNPs synthesis. In DLS analysis, AgNPs (34.26–41.14 nm) showed smaller hydrodynamic diameters than AuNPs (46.26–70.29 nm). At the same time, all values for zeta potential were negative, between − 21 and − 13 mV, suggesting good stabilities for all the colloidal MNPs systems in dispersion. TEM analysis showed that the biosynthesized AgNPs had a spherical morphology, while AuNPs were quasi-spherical, polygonal, and triangular. According to TEM data, AgNPs synthesized using aqueous and ethanolic G. urbanum rhizome extracts were characterized by mean diameters of 9.82 ± 3.68 and 14.29 ± 3.46 nm, while AuNPs by 15.88 ± 6.28 and 24.89 ± 10.75 nm, respectively. EDX analysis confirmed the presence of metallic Ag and Au in the MNPs composition by detecting strong signals at 3 (AgNPs) and 2.2 keW (AuNPs). In disc diffusion assay, MNPs showed good antimicrobial activity against Gram-positive (S. aureus MSSA, S. aureus MRSA, S. epidermidis) and Gram-negative (E. coli, P. aeruginosa, K. pneumoniae) bacteria and yeasts (C. albicans). AgNPs and AuNPs were also characterized by a significant antioxidant potential, evaluated through in vitro assays (lipoxygenase inhibition, DPPH radical scavenging activity, metal ion chelating activity, and hydroxyl radical scavenging assays). An overall better activity was obtained for the ethanolic G. urbanum rhizome extract and its derived AgNPs (EC50 = 34.2 ± 1.86 mg/mL in lipoxygenase inhibition assay). Therefore, the G. urbanum rhizome extracts proved to be excellent sources for biologically active AgNPs and AuNPs.

Characterization of the structure, antioxidant activity and hypoglycemic activity of soy (Glycine max L.) protein hydrolysates

This study aimed to hydrolyze soy isolate protein (SPI) using five enzymes (alcalase, pepsin, trypsin, papain, and bromelain) in order to obtain five enzymatic hydrolysates and to elucidate the effect of enzymes on structural and biological activities of the resulting hydrolysates. The antioxidant and hypoglycemic activities of the soy protein isolate hydrolysates (SPIEHs) were evaluated through in silico analysis, revealing that the alcalase hydrolysate exhibited the highest potential, followed by the papain and bromelain hydrolysates. Subsequently, the degree of hydrolysis (DH), molecular weight distribution (MWD), amino acid composition, structure, antioxidant activities, and hypoglycemic activity in vitro of SPIEHs were analyzed. After enzymatic treatment, the particle size, polymer dispersity index (PDI), ζ-potentials, β-sheet content and α-helix content of SPIEHs was decreased, and the maximum emission wavelength of all SPIEHs exhibited red-shifted, which all suggesting the structure of SPIEHs was unfolded. More total amino acids (TAAs), aromatic amino acids (AAAs), and hydrophobic amino acids (HAAs) were found in alcalase hydrolysate. For 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, metal ion chelating activity, α-glucosidase inhibitory activity and α-amylase inhibitory activity, alcalase hydrolysate had the lowest IC50; alcalase hydrolysate and papain hydrolysate had the lowest IC50 for hydroxyl radical scavenging activity. Physiological activity of SPIEHs was evaluated thoroughly by 5-Axe cobweb charts, and the results revealed that alcalase hydrolysate exhibited the greatest biological activities.

Improving the functionality and biological properties of Iranian date palm (Phoenix dactylifera L) seeds protein with different proteases

In this study, date seeds as a major agricultural by-product were utilized for production of antioxidant peptides with techno-functional properties. Date seeds protein (DSP) was extracted and hydrolyzed by different enzymes (Alcalase, trypsin, pancreatin and pepsin). Then, the degree of hydrolysis (DH), amino acid composition, functional characteristics (e.g., solubility, and water- and oil-holding capacity), free radical inhibiting activity, reducing power, total antioxidant activity (TAA) and metal ion chelating activity of the hydrolysates (DSPHs) were examined. Chemical analysis of the obtained protein concentrate (∼ 65 %) indicated the presence of amide A and B regions. Also, amide I to III regions and secondary structures (α-helix, β-sheet, β-tern and random coils) were observed in the extracted DSP-protein. The DH and essential amino acids content of DSPHs were affected by enzyme type. The hydrolysis treatments resulted in a significant increase in the solubility of DSP, particularly in acidic pH levels and around its isoelectric point. In comparison to DSP, DSPHs also exhibited higher inhibitory activity against free radicals such as DPPH (72.5 %), ABTS (92.5 %), OH (64.5 %), and NO (57.9 %). Furthermore, DSPHs demonstrated greater reducing power (1.84), TAA (2.3), and enhanced chelating activity towards iron (73.2 %) and copper (40.1 %) transition ions. Various factors, including DH and the composition of amino acids, especially the amount of charged, hydrophobic, and antioxidant types, have played a crucial role in these outcomes. With their significant nutritive, functional, antioxidant, and metal ion chelating activities, DSPHs can serve as a natural additive to enhance the nutritional value and stability of various food products.

Optimization of Canolol Production from Canola Meal Using Microwave Digestion as a Pre-Treatment Method.

Canola meal, the by-product of canola oil refining, is a rich source of phenolic compounds and protein. The meal, however, is primarily utilized as animal feed but represents an invaluable source of nutraceuticals. Of particular interest are the sinapates, sinapine and sinapic acid, with the decarboxylation of the latter to form canolol. Extracting these phenolics has been carried out using a variety of different methods, although there is an urgent need for environmentally safe and sustainable methods. Microwave-assisted solvent extraction (MAE), as a green extraction method, is receiving considerable interest. Its ease of use makes MAE one of the best methods for studying multiple solvents. The formation of canolol, from sinapine and sinapic acid, is primarily dependent on temperature, which favors the decarboxylation reaction. The application of MAE, using the MultiwaveTM 500 microwave system with green extractants, was undertaken to assess its ability to enhance the yield of sinapates and canolol. This study examined the effects of different pre-treatment temperature-time combinations of 140, 150, 160, and 170 °C for 5, 10, 15, 20, and 30 min on the extraction of canolol and other canola endogenous phenolic compounds. Total phenolic content (TPC), total flavonoid content (TFC), as well as metal ion chelation (MIC) and DPPH radical activity of the different extracts were assessed. The results confirmed that extractability of canolol was optimized with methanol at 151 °C and with ethanol at 170 °C with pre-treatment times of 15.43 min and 19.31 min, respectively. Furthermore, there was a strong positive correlation between TPC and TFC (p &lt; 0.05) and a negative correlation between TFC and DPPH radical activity. Interestingly, no significant correlation was observed between MIC and DPPH. These results confirmed the effectiveness of MAE, using the novel MultiwaveTM 500 microwave instrument, to enhance the yield of canolol. This was accompanied by substantial improvements in the antioxidant activity of the different extracts and further established the efficacy of the current MAE method for isolating important natural phenolic derivatives for utilization by the nutraceutical industry.

Improved Extraction Efficiency and Antioxidant Activity of Defatted Canola Meal Extract Phenolic Compounds Obtained from Air-Fried Seeds.

This study investigated the efficacy of roasting pre-treatment by air frying to enhance the extraction and recovery of the predominant sinapic acid derivatives (SADs) from roasted canola meal and the antioxidant potential of the methanolic extracts. Canola meal was obtained by air frying canola seed at 160, 170, 180 or 190 °C for 5, 10, 15 or 20 min. Oil was extracted using the Soxhlet method, and the de-oiled meal fraction was air-dried. Phenolic compounds were isolated using ultrasound-assisted extraction with 70% (v/v) methanol and then quantified by high-performance liquid chromatography-diode array detection. The antioxidant potential of the defatted meal methanolic extracts was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), and metal ion-chelating activity (MIC) assays. The highest total phenolic content of 3.15 mg gallic acid equivalent/g dry weight was recorded in the defatted meal extract from seeds pre-treated with air frying at 190 °C for 15 min. Sinapine, sinapic acid and an unknown compound at a retention time (RT) of 26.6 min were the major sinapates identified in the defatted meal with the highest concentrations of 7572 ± 479.2 µg/g DW, 727 ± 43.45 µg/g DW and 1763 ± 73.5 µg/g DW, respectively, obtained at 160 °C for 5 min. Canolol (151.35 ± 7.65 µg/g DW) was detected after air frying at a temperature of 170 °C for 20 min. The FRAP and MIC correlated positively (r = 0.85) and generally decreased with increased air frying temperature-time conditions. The highest FRAP and MIC values of 0.53 mM and 80% were obtained at 160 °C for 5 and 20 min, respectively. The outcome of this study will contribute new knowledge that could improve the value addition and by-product utilization of canola seeds.

Exploiting bioderived humic acids: A molecular combination with ZnO nanoparticles leads to nanostructured hybrid interfaces with enhanced pro-oxidant and antibacterial activity

The waste-to-wealth strategy is encouraging the design of a plethora of new value-added materials, by exploiting the chemical and biological richness of biowastes. Humic Acids (HA) are mostly intriguing because of their amphiphilic supramolecular associations which are responsible for several assets, such as adsorption ability towards small molecules, metal ion chelation, redox behavior, and antibacterial activity. The molecular combination of HA with semiconductor nanoparticles represents a valuable strategy to obtain nanostructured hybrid materials and interfaces with advanced features. Concurrently, it permits to overcome intrinsic limits of such organic fraction, including poor stability, fast conformational dynamics, or rapid reactivity in aqueous media. Herein, hybrid HA/ZnO nanoparticles are synthetized through a bottom-up strategy, exerting an improved pro-oxidant behavior by generating Reactive Oxygen Species, even without light irradiation, favoring an enhanced photocatalytic and antimicrobial activity against different bacterial pathogens. Several techniques, including SEM/TEM, DLS, ζ-potential, XRD, FTIR, TGA/DSC, EPR and DRUV, allows to define the structure-property-function relationships, thus highlighting the crucial role of a fine conjugation amongst the metal oxide precursor and bioderived fraction to drive the pro-oxidant activity. This study provides strategic guidelines to easily produce low-cost organo-inorganic nanomaterials with redox and biocide properties, aimed at coping environmental and health issues.

Anti-Inflammatory Activity of Mulberry Leaf Flavonoids In Vitro and In Vivo.

Mulberry (Morus alba L.) is a flowering tree traditionally used in Chinese herbal medicine. Mulberry leaf flavonoids (MLFs) have been reported to exert important anti-inflammatory and antioxidant properties. The purpose of this study was to select the MLF with the best anti-inflammatory and antioxidative activities from MLFs eluted by different ethanol concentrations (30%, 50%, and 75%) and explore its pharmacological properties. Three types of MLFs inhibited the production of nitric oxide (NO), prostaglandin E2 (PGE2), inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and inflammatory cytokines in lipopolysaccharide (LPS)-induced RAW 264.7 cells. All MLFs boosted the antioxidative capacity by decreasing the reactive oxygen species (ROS) production and the scavenging of 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radicals and improving the metal ion chelating activity and reducing power. The results revealed that the MLFs eluted by 30% ethanol exhibited the best anti-inflammatory and antioxidative activities. A nontargeted metabolomic analysis was used to analyze 24 types of differential flavonoids between the MLFs. Quercetin, kaempferol, and their derivatives in 30%MLF were more abundant than the other two MLFs. Furthermore, we evaluated the pharmacological activities of 30%MLF in dextran sodium sulfate (DSS)-induced ulcerative colitis (UC) mice. The 30%MLF could alleviate the clinical symptoms, reduce the secretion of inflammatory cytokines, and inhibit the activation of the inflammatory pathway in DSS-induced colitis mice. This study will provide valuable information for the development of MLFs eluted by 30% ethanol as a functional food.

Effect of solvent concentrations on antioxidant activity and biochemical parameters of adzuki bean (Vigna angularis) sprouts at different germination times

In this study were determined DPPH radical scavenging power, metal-ion chelating activity, gamma aminobutyric acid and phytic acid levels, total phenolic substance content, extraction yield in water and various organic solvents (acetone, n-hexane and ethanol), concentrations (50, 70 and 90%) and germination times (0, 24, 48, 72, 96 and 120 h) of adzuki bean (Vigna angularis) sprouts. The extraction yield ranged from 11.47% (H3) to 28.55% (E1). The highest DPPH radical scavenging capacity was determined at E2 concentration (2.978 µmol/g DW) for 120 h (P&amp;lt;0.05). E3 (1.744 mg EDTA equivalent/100 g) and A3 (1.145 mg EDTA equivalent/100 g) showed the highest metal chelating activity after 48h of germination. This activity decreased in the germination period from 48 h to 120 h (P&amp;lt;0.05). When different solvent concentrations were compared no significant change (P&amp;gt;0.05) in gamma aminobutyric acid and phytic acid contents at 0, 24 and 48 h analyses. The highest gamma aminobutyric acid content was detected to A1 (67.29 mg/100 g DW) and H1 (69.17 mg/100 g DW) concentrations at 120 h (P&amp;lt;0.05). No significant changes were found in total phenol content in all solvent concentrations in 48 h (P&amp;gt;0.05). At the end of 120 h, total phenolic components were determined in the lowest levels in W and the highest concentrations in E2 (P&amp;lt;0.05). These results showed that adzuki bean seeds may be more effective in these parameters, depending on the increase in the activities of bioactive components and the decrease in anti-nutritional factors, and the concentration in water and aqueous organic solvents with the increase of germination time.

Preparation and characterization of lipophilic antioxidative peptides derived from mung bean protein

This study aimed to prepare and characterize antioxidative hydrolysate and its lipophilic peptides derived from mung bean protein. Our results indicated that the hydrolysate prepared with 120 min hydrolysis (MPH) possessed superb DPPH, ABTS radical scavenging activity and metal ion-chelating activity with IC50 values of 11.19 ± 0.02, 18.06 ± 0.18 and 3.78 ± 0.59 µg/mL, respectively. MPH could also effectively retard lipid oxidation for oil-in-water emulsion (up to 50%) and linoleic acid (up to 94%), as well as for bulk oil. Interestingly, the lipophilic peptide fraction (MPHP) extracted from MPH could suppress the formation of primary (up to 50%) and secondary oxidation products (up to 90%) in bulk oil. Ten lipophilic peptides identified from MPHP using LC-MS/MS possessed high amounts of hydrophobic amino acids and histidine, which might favor peptides interacting and/or forming hydrogen bonds with lipid radicals. These findings provide a new perspective for lipophilic peptides in fortifying lipids as natural antioxidants.

EFFECT OF SUPPLEMENTATION OF WHEAT BRAN ON NUTRITIONAL, FUNCTIONAL AND SENSORY QUALITY OF BREAD

In present study supplementation of wheat bran with refined wheat flour was done at various levels (control to 30%) for preparation of bread which were subjected to morphological, sensory and nutritional analysis to obtain the best formulation. Nine-point hedonic test was used for sensory evaluation of prepared bread which showed increasing trends on increasing the level of wheat bran. Bread obtained by incorporating 25% wheat bran showed highest scores in terms of overall acceptability. Nutritional evaluation of supplemented bread shows the increasing trends that were ranged from 3.46-8.4% moisture, 2.5–6 % crude fat, 1.13–9.81 % crude fibre, and 0.66–4.1% ash content, while protein content (10.5–4%) was decreased with increasing of wheat bran. The functional properties of the bread were analyzed in terms of water holding capacity (3.14–5.59 ml/g), oil holding capacity (2.20–4.34 ml/g), and swelling capacity (0.68–2.45ml/g) were increase from control to 30 % supplementation of bran while bulk density (13.34-9.57 g/ml) was reduced with increasing of bran. Antioxidant compounds and their properties (Total Phenolic content, metal ion chelating activity, free radical activity and reducing power) of prepared bread were also increased as the supplementation of wheat bran was increased. Texture analyses of bread were analyzed by texture analyzer TA-XT2i in terms of hardness, cohesiveness, chewiness, gumminess and springiness. Thus supplementation of wheat bran up to 20% level would improve the nutritional quality of bread without adversely affecting the sensory parameters.

Antioxidative hydrolysates from corn gluten meal may effectively reduce lipid oxidation and inhibit HepG2 cancer cell growth

Peptides hydrolyzed from food proteins are potentially healthy antioxidants for food applications. In this study, corn gluten meal (CGM) was hydrolyzed by different enzymes to obtain antioxidative hydrolysates. The CGM hydrolysates using Neutrase was further fractionated through membrane ultrafiltration, and the medium sized fraction (F3, 3–5 kDa) exhibited promising antioxidant capacities as measured by 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity, ABTS scavenging activity, and metal ion (Fe 2+ ) chelating activity. Addition of the F3 fraction into an oil-in-water emulsion system greatly reduced the formation of primary and secondary oxidation products during 15 days incubation, with an average reduction of 82.17 and 90.71%, respectively. The F3 fraction also resulted in 49.17% reduction of lipid oxidation when added to ground pork at 1000 mg/kg. Peptide composition of the F3 fraction was further identified through RP-HPLC followed by MALDI-TOF/TOF MS analysis. The toxicity and anticancer performance of the F3 fraction was evaluated in a human hepatocarcinoma HepG2 cell line at 50 and 200 μg/mL for 6 days, resulting a significant growth inhibition by 64.2 and 71.6%, respectively. However, cell viability remained the same, indicating that the F3 peptides are not toxic for food applications as antioxidant additives. This study demonstrated that the corn gluten meal hydrolysates could be effective as antioxidants in delaying lipid oxidation and inhibiting cancel cell growth. • Corn gluten meal (CGM) is a protein-rich coproduct from corn wet milling. . • Enzymatic hydrolysis of CGM produced hydrolysates with antioxidant properties. • Adding the hydrolysate fraction improved oxidation stability of emulsion and meat. • Adding the hydrolysate fraction effectively inhibited HepG2 cancel cell growth. • Adding the peptides did not affect cell viability, implying non-toxicity for foods.

Antioxidant and Antimicrobial Peptides Derived from Food Proteins.

Recently, the demand for food proteins in the market has increased due to a rise in degenerative illnesses that are associated with the excessive production of free radicals and the unwanted side effects of various drugs, for which researchers have suggested diets rich in bioactive compounds. Some of the functional compounds present in foods are antioxidant and antimicrobial peptides, which are used to produce foods that promote health and to reduce the consumption of antibiotics. These peptides have been obtained from various sources of proteins, such as foods and agri-food by-products, via enzymatic hydrolysis and microbial fermentation. Peptides with antioxidant properties exert effective metal ion (Fe2+/Cu2+) chelating activity and lipid peroxidation inhibition, which may lead to notably beneficial effects in promoting human health and food processing. Antimicrobial peptides are small oligo-peptides generally containing from 10 to 100 amino acids, with a net positive charge and an amphipathic structure; they are the most important components of the antibacterial defense of organisms at almost all levels of life—bacteria, fungi, plants, amphibians, insects, birds and mammals—and have been suggested as natural compounds that neutralize the toxicity of reactive oxygen species generated by antibiotics and the stress generated by various exogenous sources. This review discusses what antioxidant and antimicrobial peptides are, their source, production, some bioinformatics tools used for their obtainment, emerging technologies, and health benefits.

Effect of salicylic acid and methyl salicylate treatment on polyphenol metabolites and bioactive properties of mung bean (Vigna radiata) sprouts

Present study embodies investigation on the effect of elicitors, namely methyl salicylate (MeSA) and salicylic acid (SA), along with the phenolic precursor (L-phenylalanine) on the antioxidant potential and bioactive composition of mung bean sprouts. Results showed highest increase in total phenolic, flavonoid and condensed tannin content in sprouts treated with L-phenylalanine and 1.0% MeSA (2.0-fold, 4.02-fold, and 6.75-fold, respectively as compared to control). Elicited sprouts with the similar treatment showed highest DPPH radical scavenging activity, reducing power, ferric reducing antioxidant power and metal ion chelation activity. Furthermore, 4.40 fold, 2.90 fold, and 2.81 fold increase in PAL, TAL and peroxidase activity, respectively was also observed. It may be concluded that elicitation along with phenolic precursor treatment effectively increased the bioactive content and antioxidant capacity of mung bean sprouts.

Enzymatic Hydrolysis of Broken Rice Protein: Antioxidant Activities by Chemical and Cellular Antioxidant Methods.

Excessive reactive oxygen species (ROS) is an important cause of aging, and supplementing antioxidants through diet is one of the important ways to delay aging. Some studies have confirmed that rice protease hydrolysate has antioxidant activity, but was rarely been investigated on cells. Thus, commercial enzymes, alkaline enzyme, neutral enzyme, pepsin, chymotrypsin, and trypsin were selected to hydrolyze broken rice protein (BRP) to obtain the corresponding hydrolysates, which were A-broken rice protein hydrolysate (BRPH), N-BRPH, P-BRPH, C-BRPH, and T-BRPH, respectively. Then the antioxidant properties of BRPHs were evaluated by different chemical and cellular antioxidation. Molecular weight, peptide length distribution, and amino acid sequence were detected to insight into the antioxidant properties. Among BRPHs, the A-BRPH displayed the strongest hydroxyl radical scavenging activity (IC50 = 1.159 mg/ml) and metal ion-chelating activities (IC50 = 0.391 mg/ml). Furthermore, cellular antioxidation confirmed that A-BRPH significantly increased cell viability and inhibited the intracellular ROS release in both aging cells and cell-aging processes. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) results revealed that peptides with molecular weight <14.5 KDa were produced by enzymatic hydrolysis. Additionally, A-BRPH rich in low molecular weight (<3 kDa) and short-length peptides with some specific amino acids, such as aromatic and hydrophobic amino acids, contributes to the antioxidant properties. This study provided theoretical to the utilization of broken rice and confirmed that A-BRPH could be used in new anti-aging food and health products for human consumption.

In Vitro Anti-Epstein Barr Virus Activity of Olea europaea L. Leaf Extracts.

Olea europaea L. var. sativa (OESA) preparations are widely used in traditional medicine in the Mediterranean region to prevent and treat different diseases. In this research, olive extracts derived from the leaves of the OESA tree have been screened for antioxidant activity by two methods: the DPPH free radical scavenging assay (DPPH) and the Ferric reducing antioxidant power (FRAP) assay. The DPPH assay showed that OESA possesses a stronger antioxidant activity (84%) at 1 mg/mL while the FRAP method showed a strong metal ion chelating activity (90%) at 1 mg/mL. The low IC50 values, obtained by two different methods, implies that OESA has a noticeable effect on scavenging free radicals comparable to standards. During EBV infection, the free radicals increased triggering lipid oxidation. Therefore, the monitoring of the secondary lipid peroxidation products was done by measuring malonaldehyde (MDA) and conjugated dienes (DC). The simultaneous treatment of Raji cells with OESA and TPA, as an inductorof the lytic cycle, generated a significant decrease in MDA levels and DC (p < 0.05). Besides, Raji cells simultaneously exposed to TPA and OESA exhibited a percentage of EBV-positive fluorescence cells lower than TPA treated cells (**** p < 0.0001). This suggests that OESA treatment has a protective effect against EBV lytic cycle induction.

Antimicrobial and antioxidant activities and volatile constituents of Eurhynchium angustirete (Broth.) T. J. Kop. and Isothecium alopecuroides (Lam. ex Dubois) Isov. from Turkey

The aim of the present study was to determine the chemical analysis, antimicrobial and antioxidant effects of the Eurhynchium angustirete (Broth.) and Isothecium alopecuroides (Lam. Ex Dubois) essential oil obtained by distillation method (Clevenger apparatus hydrodistillation). Obtained volatile oils were identified by gas chromatography-mass spectrometry (GC/MS) which revealed the presence of twenty-two components analyzed in the essential oil of E. angustirete representing 95.7% of the total identified compounds and twenty compounds were determined in the essential oil of I. alopecuroides representing 94.3% of the total identified compounds. Trans-pinocarveol and myrtenal as major constituents were 23.0% and 14.1% in E. angustirete and the main components were: biformene (9.9%), α-pinene (9.1%), bornyl acetate (8.4%) in I. alopecuroides. The essential oils from E. angustirete and I. alopecuroides showed higher metal-ion chelating activities which were 65.93±0.39% and 31.01±2.75, respectively. There was no significant difference results DPPH activity of essential oils 16.8±6.98 and 22.8%±8.91, respectively. The antimicrobial activity was investigated by microdiution method. The isolated essential oils were showed effective antimicrobial activities against Escherichia coli ATCC25922, Enterococcus faecalis ATCC29212, Staphylococcus aureus ATCC25923, Pseudomonas aeruginosa ATCC2785 and Streptococcus mutans. Antimicrobial effect values were found ranging of 90.76-95.38%. According to antimicrobial effect value against to microorganism, essential oil of E. angustirete was higher than I. alopecuroides.

Chemical composition and antimicrobial and antioxidant activities of essential oils of Polytrichum commune (Hedw.) and Antitrichia curtipendula (Hedw.) Brid. grown in Turkey

The aim of this study is to analyze the volatile composition and antimicrobial and antioxidant activities of the essential oils of Polytrichum commune and Antitrichia curtipendula. The essential oils obtained by hydro-distillation (HD) from each species were identified by GC-MS/FID. The main components were biformene (13.06%), α-pinene (6.53%), and bornyl acetate (8.10%) in P. commune. Nonanal and tetradecanal as major compounds were 19.96% and 20.23% in A. curtipendula essential oils, respectively. Antioxidant activity of obtained essential oils was evaluated using in-vitro antioxidant models. There was no significant difference within the groups according to DPPH activity. Also, the essential oil from P. commune showed higher metal-ion chelating activities than that of the essential oil of A. curtipendula. Metal-ion chelating activities varied between 4.1% and 67.4% at the 800 µg/mL concentration, respectively. The antimicrobial activity was tested by a minimal inhibition concentration test. Each moss species showed good antimicrobial activity against microorganisms according to the results of minimal inhibition concentration experiments.