Guidelines for antioxidant assays for food components

Novel assaying method for the accurate and rapid analysis of antioxidant total capacity based on hexachloroiridate(IV)

We introduce a novel method, namely IrRAC, for assessing total antioxidant capacity utilizing the single electron oxidant hexachloroiridate(IV). This method leverages the 488 nm absorption band of [IrCl6]2- largely reducing interferences from antioxidants and their oxidation products. [IrCl6]2- is stable 6 h in phosphate-buffered saline (PBS) ensuring consistent and reproducible absorbance readings and rendering spectrophotometric determinations under physiological neutrality. Individual assessments of 23 antioxidants reveal a linear correlation between decreasing absorbance and increasing antioxidant concentration. When the IrRAC assay was compared with several established water-based methods, strong correlations were found. Importantly, [IrCl6]2- shows a minimal oxidation of non-antioxidative substances. Moreover, IrRAC performs well with synthetic antioxidant mixtures and real samples, highlighting that the nature of antioxidants dominates the assay without much disturbance. Commercial availability of K2[IrCl6] eliminates the need of pretreatment of the oxidant. Undoubtedly, the new method confers a compelling and cost-effective alternative to the existing electron transfer-based methodologies.

The Effects of Nitrogen Application and Varietal Variation on the Product Quality and In Vitro Bioaccessibility of Bioactive Compounds of Baby Spinach Varieties Grown in a Soilless Growth Medium

Baby spinach is becoming increasingly popular as a salad ingredient and needs high fertiliser rates to grow well and attain higher-quality leaves (dark green leaves). Chemical fertilisers, especially nitrogen (N), boost yields. There are many risks associated with nitrogen fertilisation. Additionally, spinach contains phenolic compounds and carotenoids. Nitrogen fertilisation affects growth, development, yield and metabolites. This study examined the impact of lower concentrations of N (0, 30, 60, 90, 120, 150 mg/L) on yield and colour properties [light intensity (L*) colour coordinates, unique for green colour (a*) and yellow colour (b*)], as well as the impact of varying N concentrations on the total phenolic content and p-coumaric acid, quercetin, ferulic acid, kaempferol, lutein, zeaxanthin, β-carotene and antioxidant activities in the baby spinach varieties 'Acadia', 'Crosstrek' and 'Traverse', and it was established that N fertilisation improves phytochemical bioaccessibility and antioxidant activity. In a split strip plot design, three baby spinach varieties were treated with different N concentrations, including 0, 30, 60, 90, 120 and 150 mg/L. For 40 days, three baby spinach varieties were grown on soilless Mikskaar Professional substrate 300. During both seasons, 'Crosstrek' had the highest fresh mass (921.4 g/m2, 856.3 g/m2) at 120 mg/L N, while 'Traverse' had the highest fresh mass at 554.8 g/m2 and at 564.3 g/m2 at 90 mg/L N and did not differ significantly from 90 to 150 mg/L N during either season. During both seasons, 'Acadia' at 90 mg/L N increased fresh mass to 599 g/m2 and 557.9 g/m2. The variety × N supply interaction significantly affected the leaf colour; chlorophyll content across seasons; the levels of bioactive compounds, p-coumaric acid, quercetin, ferulic acid, kaempferol, lutein, zeaxanthin and β-carotene in spinach varieties; the in vitro bioaccessibility; and the antioxidant activity. Varietal differences influenced the bioaccessibility of phenolic compounds and carotenoid components. The appropriate N levels can be used during plant cultivation to optimise the bioaccessibility of this spinach variety. Thus, fertilising 'Traverse' with 90 mg/N mL increased the in vitro bioaccessibility of β-carotene (35.2%), p-coumaric acid (7.13%), quercetin (8.29%) and ferulic acid (1.92%) without compromising the yield.

Chemical and Thermal Characteristics of PEF-Pretreated Strawberries Dried by Various Methods

By increasing the permeability of the cell membrane of the treated material, pulsed electric fields (PEF) enhance the internal transport of various chemical substances. Changing the distribution of these components can modify the chemical and thermal properties of the given material. This study aimed to analyze the impact of PEF (1 kV/cm; 1 and 4 kJ/kg) applied to strawberries prior to drying by various methods (convective, infrared-convective, microwave-convective, and vacuum) on the chemical and thermal properties of the obtained dried materials (sugars content, total phenolic content, and antioxidant capacity (ABTS and DPPH assays); thermal properties (TGA and DSC); and molecular composition (FTIR)). PEF could have induced and/or enhanced sucrose inversion because, compared to untreated samples, PEF-pretreated samples were characterized by a lower share of sucrose in the total sugar content but a higher share of glucose and fructose. Reduced exposure to oxygen and decreased drying temperature during vacuum drying led to obtaining dried strawberries with the highest content of antioxidant compounds, which are sensitive to these factors. All PEF-pretreated dried strawberries exhibited a lower glass transition temperature (Tg) than the untreated samples, which confirms the increased mobility of the system after the application of an electric field.

Antioxidant Properties of Green Plants with Different Vitamin K Contents

Vitamin K, as a natural protector of our blood, bones, kidneys, and brain, is essential for human health. It is also considered an effective anti-aging agent with comprehensive biological effects, including antifungal, antibacterial, anti-inflammatory, analgesic, and even antioxidant properties. Of these, the least is known about the antioxidant properties of natural vitamin K. To fill this gap, this study compared the antioxidant properties of extracts obtained from commonly consumed green plants with different vitamin K contents with the activity of vitamin K standard solutions at concentrations corresponding to the vitamin K contents in the extracts. Various measurement methods were used in the research (i.e., DPPH, FRAP, CUPRAC, and the β-carotene bleaching test). Among the tested methods, the β-carotene bleaching test is the most sensitive in the assessment of this unusual compound. In light of the data presented, the antioxidant response of vitamin K alone is dose-dependent. However, in extracts, the activity of this compound is modulated by other constituents present in them. As a result, the activity does not always correlate with vitamin K content. The presented data supplement the knowledge about the antioxidant properties with the contribution resulting from the presence of vitamin K in green plant extracts.

Nanozyme-Catalyzed Colorimetric Detection of the Total Antioxidant Capacity in Body Fluids by Paper-Based Microfluidic Chips

Total antioxidants play a crucial role in human health, and detection of the total antioxidant capacity (TAC) has broad application prospects in fields such as food safety, environmental assessment, and disease diagnosis. However, a long detection time, cumbersome steps, high cost, reliance on professional equipment, and nonportability still remain significant challenges. In this work, an efficient strategy of point-of-care testing (POCT) of the TAC in body fluids by nanozyme-catalyzed colorimetric paper-based microfluidic sensors is proposed. The paper-based microfluidic sensors coupled with a smartphone can reduce testing costs and provide portability. The nanozyme prepared by the solvothermal method presents Michaelis constants of 0.11 and 0.129 mM for H2O2 and TMB, respectively. A method for immobilizing nanozymes and chromogenic agents on a paper-based microfluidic chip is established. Based on smartphone photography and image grayscale extraction, the TAC can be qualitatively detected with a detection limit and linear range of 33.4 and 50-700 μM, respectively. Furthermore, the proposed sensor can realize the one-step quantitative analysis of the TAC in body fluids (blood, saliva, and sweat) within 15 min. The proposed nanozyme-catalyzed colorimetric paper-based microfluidic sensors presented in this study exhibit promising application prospects in the fields of biochemical analysis and POCT.

Effects of post-fermentation addition of green tea extract for sulfur dioxide replacement on Sauvignon Blanc wine phenolic composition, antioxidant capacity, colour, and mouthfeel attributes

This study examines the feasibility of replacing SO2 in a New Zealand Sauvignon Blanc wine with a green tea extract. The treatments included the control with no preservatives (C), the addition of green tea extract at 0.1 and 0.2 g/L (T1 and T2), and an SO2 treatment at 50 mg/L (T3). Five monomeric phenolic compounds were detected in the green tea extract used for the experiment, and their concentrations ranged in the order (-)-epigallocatechin gallate > (-)-epigallocatechin > (-)-epicatechin > (-)-epicatechin gallate > gallic acid. At the studied addition rates, these green tea-derived phenolic compounds contributed to ∼70% of the antioxidant capacity (ABTS), ∼71% of the total phenolic index (TPI), and ∼ 84% of tannin concentration (MCPT) of the extract dissolved in a model wine solution. Among wine treatments, T1 and T2 significantly increased the wine's colour absorbance at 420 nm, MCPT, gallic acid and total monomeric phenolic content. TPI and ABTS were significantly higher in wines with preservatives (i.e., T2 > T1 ≅ T3 > C, p < 0.05). These variations were observed both two weeks after the treatments and again after five months of wine aging. Additionally, an accelerated browning test and a quantitative sensory analysis of wine colour and mouthfeel attributes were performed after 5 months of wine aging. When exposed to excessive oxygen and high temperature (50 °C), T1 and T2 exhibited ∼29% and 24% higher browning capacity than the control, whereas T3 reduced the wine's browning capacity by ∼20%. Nonetheless, the results from sensory analysis did not show significant variations between the treatments. Thus, using green tea extract to replace SO2 at wine bottling appears to be a viable option, without inducing a negative impact on the perceptible colour and mouthfeel attributes of Sauvignon Blanc wine.

Chemical Composition and Antibacterial, Antioxidant, and Cytotoxic Activities of Essential Oils from Leaves and Stems of Aeschynomene indica L

The objective of this study was to analyze the chemical composition and evaluate the biological capabilities of the essential oils (EOs) extracted from leaves and stems of wild Aeschynomene indica L. plants by the hydrodistillation method. By using GC-FID/MS, fifty-six and fifty-five compounds, representing 95.1 and 97.6% of the essential oils in the leaves and stems, respectively, were characterized. The predominant constituents of A. indica EOs were (E)-caryophyllene, linalool, viridiflorol, phytol, hexadecanoic acid, trans-verbenol, and α-guaiene. The antibacterial and synergistic activities of the EOs were assessed by microdilution and checkerboard assays. The results revealed a potent inhibition and bactericidal activity against Staphylococcus aureus and Bacillus subtilis with MICs of 0.312-0.625 mg/mL. When combined with traditional antibiotics, the essential oils of A. indica possessed excellent synergistic effects against all tested bacteria. Additionally, the EOs of A. indica leaves showed higher antioxidant activity (IC50 = 0.11 ± 0.01 µg/mL) compared to the stem oil (IC50 = 0.19 ± 0.01 µg/mL) using the ABTS radical scavenging assay. The in vitro cytotoxicity of EOs against human cancer cell lines HepG2, MCF-7, A-549, and HCT-116 was examined, and MTT assays showed that the EOs possessed a significant cytotoxic potential against MCF-7 breast cancer cells, with IC50 values of 10.04 ± 1.82 and 15.89 ± 1.66 μg/mL, and a moderate cytotoxic activity against other tested cells. In conclusion, the A. indica EOs could be considered a potential source of pharmacologically active compounds.

Isolation, Characterization, and Functional Properties of Antioxidant Peptides from Mulberry Leaf Enzymatic Hydrolysates

Recent evidence suggests that mulberry leaves have good antioxidant activity. However, what the antioxidant ingredient is and how the ingredient works are still not well understood. In this study, we enzymatically hydrolyze mulberry leaf proteins (MLPs) using neutral protease and find that the mulberry leaf protein hydrolysates (MLPHs) have stronger antioxidant activity compared to MLPs. We separate the core antioxidant components in MLPHs by ion-exchange columns and molecular sieves and identify 798 antioxidant peptides by LC-MS/MS. Through bioinformatics analysis and biochemical assays, we screen two previously unreported peptides, P6 and P7, with excellent antioxidant activities. P6 and P7 not only significantly reduce ROS in cells but also improve the activities of the antioxidant enzymes SOD and CAT. In addition, both peptides are found to exert protective effects against H2O2-induced chromatin damage and cell apoptosis. Collectively, these results provide support for the application of mulberry leaf peptides as antioxidants in the medical, food and livestock industries.

Antioxidant, antiglycation, and antibacterial of copper oxide nanoparticles synthesized using Caesalpinia Sappan extract

Synthesis of metal nanoparticles using plant extracts is environmentally friendly and of increasing interest. However, not all plant extracts can meet successfully on the synthesis. Therefore, searching for the high potential extracts that can reduce the metal salt precursor in the synthesis reaction is essential. The present study explores the synthesis of copper oxide nanoparticles (CuONPs) using Caesalpinia sappan heartwood extract. Phytochemical analysis and determination of the total phenolic content of the extract were performed before use as a reducing agent. Under the suitable synthesized condition, a color change in the color of the solutions to brown confirmed the formation of CuONPs. The obtained CuONPs were confirmed using ultraviolet-visible spectroscopy, photon correlation spectroscopy, X-ray diffraction, scanning electron microscope, energy dispersive X-ray, and Fourier transform infrared analysis. The synthesized CuONPs investigated for antioxidant, antiglycation, and antibacterial activities. CuONPs possessed antioxidant activities by quenching free radicals with an IC50 value of 63.35 µg/mL and reducing activity with an EC range of 3.19-10.27 mM/mg. CuONPs also inhibited the formation of advanced glycation end products in the bovine serum albumin/ribose model with an IC50 value of 17.05 µg/mL. In addition, CuONPs showed inhibition of human pathogens, including Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli, and prevention of biofilm formation and biofilm eradication, with maximum inhibition of approx. 75%. Our findings suggest that C. sappan extract can be used to obtain highly bioactive CuONPs for the development of certain medical devices and therapeutic agents.

Antibacterial Activity Potential of Industrial Food Production Waste Extracts against Pathogenic Bacteria: Comparative Analysis and Characterization

The Food and Agricultural Organization estimates a 17% loss in the food production chain, making it imperative to adopt scientific and technological approaches to address this issue for sustainability. Industrial food production waste and its value-added applications, particularly in relation to a wide variety of pathogenic microorganisms and the health-related effects have not been thoroughly investigated. This study explores the potential of food production waste extracts-lemon peel (LP), hot trub (HT), and coffee silverskin (CSS) as sources of bioactive compounds. Extraction was conducted using hydro-methanolic extraction with yields in LP (482 mg/1 g) > HT (332 mg/1 g) > CSS (20 mg/1 g). The agar diffusion assay revealed the substantial antibacterial activity of all three extracts against Erwinia Amylovora, Escherichia coli, Bacillus subtilis, and Bacillus aquimaris. All extracts demonstrated activity against Gram-positive and Gram-negative bacteria, displaying minimum inhibitory concentrations effective against pathogenic bacteria like Listeria monocytogenes, Staphylococcus aureus, Vibrio parahaemolyticus, and Salmonella enterica. Total phenolic content (TPC in mg GAE/1g) was 100, 20, and 100 for CSS, HT, and LP, respectively. Antioxidant activity by ABTS indicated IC50 of 3.09, 13.09, and 2.61 for LP, HT, and CSS, respectively. Also, the antioxidant activity of the extracts was further confirmed by DPPH assay with the best activity in CSS (9.84 GAEg-1) and LP (9.77 mg of GAEg-1) rather than in HT (1.45 GAEg-1). No adverse cytotoxic effects on HaCaT cells were observed. Pancreatic amylase inhibition demonstrated antidiabetic potential, with LP showing the highest levels (92%). LC-MS characterization identified polyphenols as the main compounds in CSS, prenylated compounds in HT, and flavanols in LP. The findings imply the potential sustainable use of food production waste in industry.

Comparison of Polylactide-Based Active Films Containing Berberine and Quercetin as Systems for Maintaining the Quality and Safety of Blueberries

Polymeric thin films based on polylactide with an addition of poly(ethylene glycol) as a plasticizer and flavonoids in the form of quercetin and berberine were subjected to tests that were particularly relevant from the point of view of contact with food. A comparative analysis of the effect of individual flavonoids on the antioxidative properties of tested films and blueberry storage was carried out. The influence of active compounds on the water vapor permeability, as well as UV protection, of the obtained materials was investigated. Also, the specific migration of individual flavonoids from obtained materials to food simulants in the form of acetic acid and ethyl alcohol was determined. The crucial point of this study is the storage of blueberries. The obtained results indicate that the selection of packaging, containing individual active compounds, depends on the purpose and requirements that the packaging must meet for particular types of food.

Comparative analysis of antioxidant and fatty acid composition in avocado (Persea americana Mill.) fruits: Exploring regional and commercial varieties

On Madeira Island, Portugal, the avocado crop benefits from a Mediterranean climate, exhibiting exceptional phytochemical and biochemical properties. Aiming to evaluate the antioxidant quality and fatty acid composition with a commercial avocado, flours were obtained from five varieties (four regional and one commercial Hass) across different tissues (pulp and by-products) and cycles (years and on-tree maturation stages). Results showed that a regional variety with thin purple skin had the highest antioxidant qualities and lipid content, surpassing the other regional and commercial Hass varieties. Oleic acid prevailed in all samples, with regional avocados containing arachidonic acid which is an uncommon occurrence among higher plants. Variations in fatty acid content were influenced by the timing of harvest. These outcomes highlight the promising potential of avocados from Madeira Island.

Enhancing Phycocyanobilin Production Efficiency in Engineered Corynebacterium glutamicum: Strategies and Potential Application

Phycocyanobilin, an algae-originated light-harvesting pigment known for its antioxidant properties, has gained attention as it plays important roles in the food and medication industries and has surged in demand owing to its low-yield extraction from natural resources. In this study, engineered Corynebacterium glutamicum was developed to achieve high PCB production, and three strategies were proposed: reinforcement of the heme biosynthesis pathway with the introduction of two PCB-related enzymes, strengthening of the pentose phosphate pathway to generate an efficient cycle of NADPH, and fed-batch fermentation to maximize PCB production. Each approach increased PCB synthesis, and the final engineered strain successfully produced 78.19 mg/L in a flask and 259.63 mg/L in a 5 L bioreactor, representing the highest bacterial production of PCB reported to date, to our knowledge. The strategies applied in this study will be useful for the synthesis of PCB derivatives and can be applied in the food and pharmaceutical industries.

Improving the Antioxidant and Anti-Inflammatory Activity of Fermented Milks with Exopolysaccharides-Producing Lactiplantibacillus plantarum Strains

Exopolysaccharides (EPSs) producing lactic acid bacteria have been claimed to confer various health benefits to the host, including the ability to face oxidative and inflammatory-related stress. This study investigated the ability of food-borne Lactiplantibacillus (Lpb.) plantarum to improve the antioxidant activity of fermented milks by producing EPSs. Two Lpb. plantarum strains, selected as lower and higher EPSs producers, have been applied in lab-scale fermented milk production, in combination with conventional starters. Antioxidant activity was investigated in vitro using DPPH (1,1-diphenyl-2-picrylhydrazyl), ABTS (2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), and FRAP (ferric reducing antioxidant power) assays while the ability to modulate reactive oxygen species (ROS) level was evaluated in an intestinal healthy model, subjected to both oxidative and inflammatory stress. Furthermore, to verify whether digestion affects functionality, fermented milks were evaluated before and after in vitro-simulated INFOGEST digestion. The results showed an improved antioxidant activity of fermented milk enriched with Lpb. plantarum LT100, the highest EPSs producer. Furthermore, the data showed a different ROS modulation with a protective anti-inflammatory effect of samples enriched with Lpb. plantarum strains. Our data suggest the use of selected EPS-producing strains of Lpb. plantarum as a natural strategy to enrich the functionality of fermented milks in terms of ROS modulation and inflammatory-related stress.

Ethanolic Extract from Fruits of Pintoa chilensis, a Chilean Extremophile Plant. Assessment of Antioxidant Activity and In Vitro Cytotoxicity

Pintoa chilensis is a shrub with yellow flowers that reach up to two meters high, endemic of the Atacama Region in Chile. This species grows under special environmental conditions such as low altitude, arid areas, and directly sun-exposed habitats. In the present study, ethanolic extract was obtained from fruits of P. chilensis, and then partitioned in solvents of increasing polarity to obtain five fractions: hexane (HF), dichloromethane (DF), ethyl acetate (AF), and the residual water fraction (QF). The antioxidant activity of extracts was evaluated by using the DPPH, ABTS, and FRAP methods. The results show that the antioxidant capacity of P. chilensis is higher than that reported for other plants growing in similar environments. This effect is attributed to the highest content of flavonoids and total phenols found in P. chilensis. On the other hand, the cell viability of a breast cancer cell line (MCF-7) and a non-tumor cell line (MCF-10A) was assessed in the presence of different extract fractions. The results indicate that the hexane fraction (HF) exhibits the highest cytotoxicity on both cell lines (IC50 values equal to 35 and 45 µg/mL), whereas the dichloromethane fraction (DF) is the most selective one. The GC-MS analysis of the dichloromethane fraction (DF) shows the presence of fatty acids, sugars, and polyols as major components.

Valorization of a Local Italian Pear (Pyrus communis L. cv. 'Petrucina')

In recent decades, the food production chain has undergone transformations that have profoundly affected the way food is supplied, causing changes in the quality of the final products. Moreover, biodiversity is seriously threatened worldwide, and the valorization of local germplasm is a priority goal for most sectorial policies in Europe and elsewhere. Southern Italy and the Mediterranean basin present a vast heritage of fruit tree cultivars that is gradually being lost. Through this work, we aim to valorize a well-adapted local pear cultivar named Petrucina from the Salento area (southeastern Italy, Apulia region), which has never been studied before in detail. With this aim, the nutritional and nutraceutical features of pear flesh were characterized and compared with a reference pear cultivar that is widespread and well-known in Europe (cv. 'Conference'). Petrucina fruits have shown a peculiar aromatic compound profile, and a content of up to 398.3, 30.9, and 4.7 mg/100 g FW of malic acid, citric acid, and ascorbic acid, respectively, much higher than that of Conference fruits. Additionally, Petrucina flesh presents a more than triple total phenolic content and an antioxidant activity more than double that of Conference, making Petrucina a true functional food that deserves wide appreciation.

Untargeted metabolomics and molecular docking studies on green silver nanoparticles synthesized by Sarocladium subulatum: Exploring antibacterial and antioxidant properties

The biological synthesis of silver nanoparticles (Ag-NPs) with fungi has shown promising results in antibacterial and antioxidant properties. Fungi generate metabolites (both primary and secondary) and proteins, which aid in the formation of metal nanoparticles as reducing or capping agents. While several studies have been conducted on the biological production of Ag-NPs, the exact mechanisms still need to be clarified. In this study, Ag-NPs are synthesized greenly using an unstudied fungal strain, Sarocladium subulatum AS4D. Three silver salts were used to synthesize the Ag-NPs for the first time, optimized using a cell-free extract (CFE) strategy. Additionally, these NPs were assessed for their antimicrobial and antioxidant properties. Various spectroscopic and microscopy techniques were utilized to confirm Ag-NP formation and analyze their morphology, crystalline properties, functional groups, size, stability, and concentrations. Untargeted metabolomics and proteome disruption were employed to explore the synthesis mechanism. Computational tools were applied to predict metabolite toxicity and antibacterial activity. The study identified 40 fungal metabolites capable of reducing silver ions, with COOH and OH functional groups playing a pivotal role. The silver salt type impacted the NPs' size and stability, with sizes ranging from 40 to 52 nm and zeta potentials from -0.9 to -30.4 mV. Proteome disruption affected size and stability but not shape. Biosynthesized Ag-NPs using protein-free extracts ranged from 55 to 62 nm, and zeta potentials varied from -18 to -27 mV. Molecular docking studies and PASS results found no role for the metabolome in antibacterial activity. This suggests the antibacterial activity comes from Ag-NPs, not capping or reducing agents. Overall, the research affirmed the vital role of specific reducing metabolites in the biosynthesis of Ag-NPs, while proteins derived from biological extracts were found to solely affect their size and stability.

Berberis integerrima bioactive molecules loaded in chitosan-based electrospun nanofibers for soybean oil oxidative protection

Natural bioactive molecules such as phenolic acids and alkaloids play a crucial role in preserving the quality and safety of food products, particularly oils, by preventing oxidation. Berberis integerrima, a rich source of such antioxidants, has been explored in this study for its potential application in soybean oil preservation. Electrospun nanofibers, composed of polyvinyl alcohol and chitosan, were fabricated and loaded with an alcoholic extract of Berberis integerrima. The antioxidant activity of Berberis integerrima was evaluated, and the phenolic compounds contributing to its efficacy were identified and quantified. The physicochemical properties of the polyvinyl alcohol /chitosan/Berberis integerrima nanofibers, including morphology, crystallinity, functional groups, and thermal stability, were characterized. The results revealed that the polyvinyl alcohol/chitosan/Berberis integerrima nanofibers exhibited high antioxidant capacity and improved the stability of Berberis integerrima, indicating their potential as effective and biodegradable materials for food preservation. This study underscores the potential of harnessing natural antioxidants from Berberis integerrima in nanofibers to enhance the quality and safety of soybean oil.

Exploring the Wound Healing Potential of a Cuscuta chinensis Extract-Loaded Nanoemulsion-Based Gel

Cuscuta chinensis (C. chinensis) presents many pharmacological activities, including antidiabetic effects, and antioxidant, anti-inflammatory, and antitumor properties. However, the wound care properties of this plant have not yet been reported. Therefore, this research aimed to evaluate the antioxidant, anti-inflammatory, and antibacterial activities of ethanol and ethyl acetate C. chinensis extracts. The phytochemical markers in the extracts were analyzed using high-performance liquid chromatography (HPLC). Then, the selected C. chinensis extract was developed into a nanoemulsion-based gel for wound care testing in rats. The results showed that both of the C. chinensis extracts exhibited antioxidant activity when tested using 2,2-Diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), and lipid peroxidation inhibition assays. They reduced the expression of IL-1β, IL-6, and TNF-α in RAW264.7 cells induced with lipopolysaccharide (LPS). The ethyl acetate extract also had antibacterial properties. Kaempferol was found in both extracts, whereas hyperoside was found only in the ethanol extract. These compounds were found to be related to the biological activities of the extracts, confirmed via molecular docking. The C. chinensis extract-loaded nanoemulsions had a small particle size, a narrow polydispersity index (PDI), and good stability. Furthermore, the C. chinensis extract-loaded nanoemulsion-based gel had a positive effect on wound healing, presenting a better percentage wound contraction Fucidin cream. In conclusion, this formulation has the potential for use as an alternative wound treatment and warrants further study in clinical trials.

Synthesis, theoretical analysis, and biological properties of a novel tridentate Schiff base palladium (II) complex

Schiff base complexes play a crucial role in bioinorganic chemistry. A novel curcumin/phenylalanine tridentate Schiff base ligand and its palladium (II) complex were synthesized so that they were stable in aqueous buffer. The structure of the complex was investigated using a variety of methods, including DFT, NBO analysis, FMOs, and MESP. The interaction of the complex with a plasmid (pUC19) and CT-DNA was studied. The anticancer, antibacterial, and antioxidant activities of the complex were examined. The statistical analysis of the MTT assay was compared using the 1-way ANOVA and Tukey test. Results showed that the complexes were stable in aqueous buffer, pH 8. The extrinsic fluorescence emission of the plasmid and CT-DNA was quenched while interacting with the complex. The complex had an IC50 of 72.47 µM against MCF-7 cells. The ANOVA and Tukey analysis of MTT data demonstrated a statistically significant difference between groups (P < 0.0001). The minimum inhibitory concentrations (MIC) of the complex for E. coli and S. aureus were 300 and 200 µg/mL, with 96.3 and 95.2% biofilm growth inhibition at 250 µg/mL, respectively. The sample concentrations contributing to 50% radical inhibition in the 1,1-diphenyl-2-picrylhydrazyl (DPPH) test for curcumin, ligand, and palladium (II) complex were 33.62, 21.27, and 51.26 µM, respectively. The results suggest that the complex interaction with DNA is one of the potential mechanisms for eliminating cancer cells and bacteria in the planktonic and biofilm. On the other hand, while stability in an aqueous buffer at pH 8 increases, the modified curcumin antioxidant effect decreases.

Melanoidin-like carbohydrate-containing macromolecules from Shanxi aged vinegar exert immunoenhancing effects on macrophage RAW264.7 cells

Bioactive macromolecule mining is important for the functional chemome analysis of traditional Chinese vinegar. In this study, we isolated and characterized carbohydrate-containing macromolecules from Shanxi aged vinegar (CCMSAV) and evaluated their immunomodulatory activity. The isolation process involved ethanol precipitation, deproteinization, decolorization, and DEAE-650 M column chromatography, resulting in the acquisition of four sub-fractions. All sub-fractions exhibited a molecular weight range of 6.92 to 16.71 kDa and were composed of 10 types of monosaccharides. Comparative analysis of these sub-fractions with two melanoidins exhibited similarities in elemental composition, spectral signature, and pyrolytic characteristics. Immunological assays confirmed the significantly enhanced cell viability, phagocytic activity, and secretion of nitric oxide, tumor necrosis factor (TNF)-α and interleukin (IL)-6 in RAW264.7 cells by all four sub-fractions. Further investigation of the immunomodulatory mechanism revealed that SAV-RP70-X, the most potent purified sub-fraction, enhanced aerobic glycolysis in macrophages and activated Toll-like receptor 2 (TLR2), TLR4, mannose receptor (MR), scavenger receptor (SR), and the dendritic cell-associated C-type lectin-1 receptor (Dectin-1). Furthermore, the activation of macrophages was associated with the MyD88/PI3K/Akt/NF-κB signaling pathway. Methylation analysis revealed that 1,4-Xylp was the most abundant glycosidic linkage in SAV-RP70-X.

Chitosan hydrogels enriched with bioactive phloroglucinol for controlled drug diffusion and potential wound healing

We report a facile strategy to prepare chitosan (CS) hydrogels that eliminates the need for chemical crosslinking for advanced biomedical therapies. This approach gives controlled properties to the hydrogels by incorporating a natural bioactive phenolic compound, phloroglucinol (PG), into their microstructure. The adsorption of PG onto CS chains enhanced the hydrogels' antioxidant activity by up to 25 % and resulted in a denser, more entangled structure, reducing the pore size by 59 μm while maintaining porosity above 94 %. This allowed us to finely adjust pore size and swelling capacity. These structural properties make these hydrogels well-suited for wound healing dressings, promoting fibroblast proliferation and exhibiting excellent hemocompatibility. Furthermore, to ensure the versatility of these hydrogels, herein, we demonstrate their potential as drug delivery systems, particularly for dermal infections. The drug release can be controlled by a combination of drug diffusion through the swollen hydrogel and relaxation of the CS chains. In summary, our hydrogels leverage the synergistic effects of CS's antibacterial and antifungal properties with PG's antimicrobial and anti-inflammatory attributes, positioning them as promising candidates for biomedical and pharmaceutical applications, more specifically in advanced wound healing therapies with local drug delivery.

Biosynthesized silver nanoparticles prevent bacterial infection in chicken egg model and mitigate biofilm formation on medical catheters

Investigating the application of innovative antimicrobial surface coatings on medical devices is an important field of research. Many of these coatings have significant drawbacks, including biocompatibility, coating stability and the inability to effectively combat multiple drug-resistant bacteria. In this research, we developed an antibiofilm surface coating for medical catheters using biosynthesized silver nanoparticles (b-Cs-AgNPs) developed using leaves extract of Calliandra surinamensis. Various characterization techniques were employed to thoroughly characterize the synthesized b-Cs-AgNPs and c-AgNPs. b-Cs-AgNPs were compatible with human normal kidney cells and chicken embryos. It did not trigger any skin inflammatory response in in vivo rat model. b-Cs-AgNPs demonstrated potent zone of inhibition of 19.09 mm when subjected to the disc diffusion method in E. coli confirming strong antibacterial property. Different anti-bacterial assays including liquid growth curve, colony counting assay, biofilm formation assay supported the potent antimicrobial efficacy of b-Cs-AgNPs alone and when coated to medical grade catheters. Mechanistic studies reveal the presence of ferulic acid, that was important for the synthesis of b-AgNPs along with enhanced antibacterial effects of b-Cs-AgNPs compared to c-AgNPs, supported by molecular docking analysis. These results together demonstrated the effective role b-Cs-AgNPs in combating infections and mitigating biofilm formations, highlighting their need for further study in the field of biomedical applications.

The evaluation of catechins reducing heterocyclic aromatic amine formation: Structure-activity relationship and mechanism speculation

The favorable inhibitory effect of tea polyphenols on heterocyclic aromatic amines (HAAs) has been confirmed in many past studies. The objective of this study was to investigate the structure-activity relationship of catechins that act as inhibitors of HAA formation in chemical models. Two kinds of quantitative structure-activity relationship models for catechin-inhibiting-HAA were established. We chose two kinds of HAAs including 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) and 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), and five catechins including epigallocatechin gallate (EGCG), epicatechin gallate (ECG), epigallocatechin (EGC), epicatechin (EC), and catechin (C). The inhibitory effect of five catechins were in the following order: EGCG > ECG > EGC > C > EC. Thereinto, EGCG and ECG showed dramatically better inhibition on the formation of PhIP and MeIQx, especially EGCG. Further, the mechanisms of catechin-inhibiting-HAA were speculated by correlation analysis. The free radical-scavenging ability was predicted to be the most relevant to the inhibitory effect of ECG, EGC, EC and C on HAAs. Differently, the phenylacetaldehyde-trapping ability might be the more important mechanism of EGCG inhibiting PhIP in chemical model system. This study may bring a broader idea for controlling the formation of HAAs according to the structure of catechins.

Overproduction of Xanthophyll Pigment in Flavobacterium sp. JSWR-1 under Optimized Culture Conditions

Flavobacterium can synthesize xanthophyll, particularly the pigment zeaxanthin, which has significant economic value in nutrition and pharmaceuticals. Recently, the use of carotenoid biosynthesis by bacteria and yeast fermentation technology has shown to be very efficient and offers significant advantages in large-scale production, cost-effectiveness, and safety. In the present study, JSWR-1 strain capable of producing xanthophyll pigment was isolated from a freshwater reservoir in Wanju-gun, Republic of Korea. Based on the morphological, physiological, and molecular characteristics, JSWR-1 classified as belonging to the Flavobacterium species. The bacterium is strictly aerobic, Gram-negative, rod-shaped, and psychrophilic. The completed genome sequence of the strain Flavobacterium sp. JSWR-1 is predicted to be a single circular 3,425,829-bp chromosome with a G+C content of 35.2% and 2,941 protein-coding genes. The optimization of carotenoid production was achieved by small-scale cultivation, resulting in zeaxanthin being identified as the predominant carotenoid pigment. The enhancement of zeaxanthin biosynthesis by applying different light-irradiation, variations in pH and temperature, and adding carbon and nitrogen supplies to the growth medium. A significant increase in intracellular zeaxanthin concentrations was also recorded during fed-batch fermentation achieving a maximum of 16.69 ± 0.71 mg/l, corresponding to a product yield of 4.05 ± 0.15 mg zeaxanthin per gram cell dry weight. Batch and fed-batch culture extracts exhibit significant antioxidant activity. The results demonstrated that the JSWR-1 strain can potentially serve as a source for zeaxanthin biosynthesis.

De novo antioxidant peptide design via machine learning and DFT studies

Antioxidant peptides (AOPs) are highly valued in food and pharmaceutical industries due to their significant role in human function. This study introduces a novel approach to identifying robust AOPs using a deep generative model based on sequence representation. Through filtration with a deep-learning classification model and subsequent clustering via the Butina cluster algorithm, twelve peptides (GP1-GP12) with potential antioxidant capacity were predicted. Density functional theory (DFT) calculations guided the selection of six peptides for synthesis and biological experiments. Molecular orbital representations revealed that the HOMO for these peptides is primarily localized on the indole segment, underscoring its pivotal role in antioxidant activity. All six synthesized peptides exhibited antioxidant activity in the DPPH assay, while the hydroxyl radical test showed suboptimal results. A hemolysis assay confirmed the non-hemolytic nature of the generated peptides. Additionally, an in silico investigation explored the potential inhibitory interaction between the peptides and the Keap1 protein. Analysis revealed that ligands GP3, GP4, and GP12 induced significant structural changes in proteins, affecting their stability and flexibility. These findings highlight the capability of machine learning approaches in generating novel antioxidant peptides.

The Effects of Sunflower and Maize Crop Residue Extracts as a New Ingredient on the Quality Properties of Pork Liver Pâtés

The present study aimed to evaluate the antioxidant capacity of ethanolic extracts from post-harvest sunflower and maize stalk residues, and their impact on the chemical composition, physicochemical parameters, lipid oxidative stability, microbiological properties, and sensory characteristics of pork liver pâtés over a 90-day storage period. Four formulations were prepared: a control group (CON), a batch with butylated hydroxytoluene as a synthetic antioxidant (BHT), 1% ethanolic extract from sunflower residues (SSRE), and 1% ethanolic extract from maize residues (MSRE). The MSRE had a higher total phenol content and showed better antioxidant activity relative to the SSRE (p < 0.01). The addition of SSRE decreased the lightness and increased the redness in the pork liver pâtés, with these pâtés showing the highest total color difference compared to the control (p < 0.01). The crop extracts increased the n-6 and total PUFA contents in pâtés and improved the PUFA/SFA ratio (p < 0.01). Formulations containing crop residue extracts showed higher TBARs and POV values than the control and BHT group (p < 0.01), indicating a pro-oxidant effect and accelerated lipid oxidation in pâtés during storage. As far as microbiological quality, the presence of crop residue extracts decreased the total viable count, lactic acid bacteria, and psychotropic aerobic bacteria (p < 0.01). The incorporation of crop extracts in the pork pâtés impaired their sensory quality, particularly color, odor, aroma, and flavor, and decreased their overall acceptability. These results indicated that, while the crop residue extracts were not as effective as synthetic antioxidants in preserving the lipid stability of pâtés, they demonstrated potential for enhancing the microbial quality of this type of meat product.

Unlocking peach juice byproduct potential in food waste biorefineries: Phenolic compounds profile, antioxidant capacity and fermentable sugars

This work assesses an integrated pathway for the revalorization of peach byproduct (PB) within a biorefinery. PB was subjected to an oven-drying (OD) treatment for its evaluation as a storage treatment. It was compared to freeze-drying and untreated material in terms of antioxidant capacity (AOC), phenolic compounds (PC) profile and fermentable sugar production. OD reduced the water content to less than 15 % while preserving the bound hydrolysable polyphenols, which were the more abundant PC (≈64 %) with the highest AOC. Drying treatments hampered polysaccharide accessibility, but some enzyme preparations released 60-70 g/L of fermentable sugars at relatively high solids loading (10 %). This study proposes a novel enzyme-based strategy for the valorisation of fermentable sugars and antioxidant compounds from PB. The sugars can be fermented into several building blocks while the solid residue enriched in recalcitrant phenolic compounds and proteins could be used to develop novel functional products for food/feed sectors.

Exploring the antioxidant and antimicrobial potential of three common seaweeds of Saint Martin's Island of Bangladesh

Antioxidants, which have long been deemed an indispensable guardian of human health, play a pivotal role in bolstering the body's defense against a plethora of diseases. Three well-recognized seaweeds in Bangladesh, including Caulerpa racemosa, Padina tetrastromatica, and Hypnea musciformis, were subjected to meticulous analysis to reveal their phytochemical composition, antioxidant activity, and antimicrobial efficacy using advanced spectroscopic and disc diffusion methods. Intriguingly, we observed that C. racemosa emerges as frontrunners, possessing a substantial arsenal of phenol (143.08 ± 18.51 mg gallic acid equivalent g─1) and flavonoid (63.79 ± 2.16 mg rutin equivalent g─1). More fundamentally, C. racemosa exhibits a notable enrichment in the content of tannin (73.58 mg RE g─1) and chlorophyll (13.50 mg g─1), as well as, antioxidant capacity (4457.67 μg g─1). P. tetrastromatica, on the other hand, displayed commendable effectiveness in scavenging the DPPH radical, with percentages ranging from 53.98 to 62.17%. In terms of hydroxyl radical (OH•) scavenging activity, C. racemosa exhibited the highest efficacy at 400 g mL─1. Fascinatingly, C. racemosa exhibited an impressive antioxidant potential, as evidenced by its exceptionally low IC50 value of 5.58 μg mL-1 for OH• scavenging, whereas P. tetrastromatica showed impressively low value of 0.96 μg mL-1 for DPPH scavenging. Although the three seaweeds demonstrated limited efficacy against a spectrum of five human pathogenic bacteria, their potential as abundant sources of antioxidants remains unscathed. Notably, heatmap and PCA analysis revealed that C. racemosa and P. tetrastromatica emerge as the leading contender for studied antioxidant compounds, demonstrating their proclivity for antioxidant extraction, a trait that could be exploited for large-scale production of these valuable compounds.

Conjugation of lesser mealworm (Alphitobius diaperinus) larvae protein with polyphenols for the development of innovative antioxidant emulsifiers

Lesser mealworm protein concentrate (LMPC) was conjugated with chlorogenic acid (CA) or tannic acid (TA) using an alkaline method. The impact of polyphenol type and concentration on the physicochemical and structural characteristics, antioxidant, interfacial, and emulsifying properties of the LMPC-polyphenol conjugates were investigated. Under the conditions tested, TA demonstrated higher affinity for LMPC compared to CA. The conjugation of LMPC induced conformational changes as showed by intrinsic fluorescence and FT-MIR raw spectra analysis. The surface hydrophobicity of the conjugates was reduced, leading to increased interfacial tension values for LMPC-TA conjugates without impairment of the emulsifying activity. The antioxidant properties were significantly improved by the conjugation. Flaxseed oil-in-water (O/W) emulsions stabilized by the conjugates and LMPC remained physically stable for 12 days at 50 °C with a notable reduction of secondary oxidation products when conjugates were used. LMPC-TA and LMPC-CA exhibited potential to be used as novel antioxidant emulsifiers in O/W emulsions.

Synthesis of New Chiral β-Carbonyl Selenides with Antioxidant and Anticancer Activity Evaluation-Part I

A series of unsymmetrical phenyl β-carbonyl selenides with o-amido function substituted on the nitrogen atom with chiral alkyl groups was obtained. The compounds form a series of enantiomeric and diastereomeric pairs and present the first examples of this type of chiral Se derivatives. All obtained selenides were further evaluated as antioxidants and anticancer agents to define the influence of the particular stereochemistry of the attached functional groups on the bioactivity of the molecules. The highest H2O2 reduction potential was observed for N-(cis-2-hydroxy-1-indanyl)-2-((2-oxopropyl)selanyl)benzamide, and the best radical scavenging properties for N-(-1-hydroxy-2-butanyl)-2-((2-oxopropyl)selanyl)benzamide. Also, both enantiomers of the N-(1-hydroxy-2-butanyl) selenide expressed the highest cytotoxic potential towards human promyelocytic leukemia HL-60 cell line with similar IC50 values 14.4 ± 0.5 and 16.2 ± 1.1 µM, respectively. On the other hand, breast cancer cell line MCF-7 was most sensitive to N-((R)-(-)-1-hydroxy-2-butanyl)- 2-((2-oxopropyl)selanyl)benzamide (IC50 of 35.7 ± 0.6 µM). The structure-activity dependence of the obtained Se derivatives was discussed, and the most potent compounds were selected.

Development of safe and antioxidant COX-2 inhibitors; Synthesis, molecular docking analysis and biological evaluation of novel pyrrolizine 5-carboxamides

In the current study, a series of new pyrrolizine-5-carboxamide derivatives (5-8, 9a-d, 10a-d, 11a,b and 12a,b) were developed, synthesized and evaluated in terms of in vitro COX-2 enzyme inhibition. The in vivo anti-inflammatory evaluation was conducted on the most selective compounds (9a,b,d, 10b,c and 11a,b). For the most active five compounds (9a, 10b,c and 11a,b), ulcerogenic liability, histopathological examinations, physicochemical properties study and antioxidant activity were investigated. Also, nitric oxide donor activity was evaluated for compounds (6, 7, 10a-d and 12a,b), while, compounds (10c,d and 12a,b) showed a high significant result relative to the normal control. According to the findings of this study, 2,3-dihydro-1H-pyrrolizine-5-carboxamide (9a) demonstrated high antioxidant (highest beta-carotene concentration (10.825 µg/ml)) and anti-inflammatory activity (EIP = 63.6 %) with lower ulcerogenicity (ulcer index 13.67), presenting it as a promising candidate for treating inflammatory diseases which are complicated by oxidative tissue damage. Furthermore, MOE software tools docking software was used to carry out the in silico studies. Docking study for the most active compounds showed that all compounds made three to four H-bond interactions in COX-2 active site adopting excellent docking scores.

Antimicrobial and antioxidant activity of encapsulated tea polyphenols in chitosan/alginate-coated zein nanoparticles: a possible supplement against fish pathogens in aquaculture

Regulation of antibiotic use in aquaculture calls for the emergence of more sustainable alternative treatments. Tea polyphenols (GTE), particularly epigallocatechin gallate (EGCG), have various biological activities. However, tea polyphenols are susceptible to degradation. In this work, EGCG and GTE were encapsulated in zein nanoparticles (ZNP) stabilized with alginate (ALG) and chitosan (CS) to reduce the degradation effect. ALG-coated ZNP and ALG/CS-coated ZNP encapsulating EGCG or GTE were obtained with a hydrodynamic size of less than 300 nm, an absolute ζ-potential value >30 mV, and an encapsulation efficiency greater than 75%. The antioxidant capacity of the encapsulated substances, although lower than that of the free ones, maintained high levels. On the other hand, the evaluation of antimicrobial activity showed greater efficiency in terms of growth inhibition for ALG/CS-ZNP formulations, with average overall values of around 60%, reaching an inhibition of more than 90% for Photobacterium damselae. These results support encapsulation as a good strategy for tea polyphenols, as it allows maintaining significant levels of antioxidant activity and increasing the potential for antimicrobial activity, in addition to increasing protection against sources of degradation.

Antibacterial and antioxidant potential analysis of Verbascum sinaiticum leaf extract and its synthesized silver nanoparticles

The potential applications of plant extract and nanoparticles in antibacterial and antioxidant studies have garnered significant interest in recent times. Despite being utilized in Ethiopian traditional medicine, Verbascum sinaiticum (qetetina) constituents and its usage in nanoparticle synthesis remain relatively unexplored. This study explores the potential of the plant extract and its nanoparticles for antibacterial and antioxidant applications, with a focus on the leaf extracts and its silver nanoparticles. The leaf extract was analyzed using LC-MS and GC-MS and found to contain over 70 compounds, including glycosides, phenolic compounds, flavonoids, and fatty acids. The synthesized nanoparticles had a maximum absorbance of 408 nm, with a size range of 2-40 nm and showed a spherical shape. Using the agar well diffusion method, the extract and nanoparticles were evaluated against Gram-positive (Staphylococcus aureus ATCC 2592, Streptococcus agalactia ATCC12386) and Gram-negative bacteria (Acinetobacter baumannii ATCC19606, Pseudomonas aeruginosa ATCC27853) bacterial strains. In terms of antibacterial effects, both the silver nanoparticles and leaf extract displayed a greater impact on gram-positive bacterial strains over gram-negative bacterial strains. Additionally, the tests for lowest inhibitory and bactericidal concentration indicated similar outcomes. Notably, the silver nanoparticles exhibited greater antibacterial activity compared to the leaf extract alone. The DPPH (2, 2-diphenylpicrylhydrazyl) assay was conducted to investigate antioxidant activity. The results showed that the plant extract had an IC50 value of 143 μg/ml, while the synthesized nanoparticle had an IC50 value of 216 μg/ml, indicating that the plant extract had greater antioxidant activity than the synthesized silver nanoparticles.

Extracts with Nutritional Potential and Their Influence on the Rheological Properties of Dough and Quality Parameters of Bread

Formulating basic food to improve its nutritional profile is one potential method for food innovation. One option in formulating basic food such as bread is to supplement flours with specified amounts of non-bakery raw materials with high nutritional benefits. In the research presented here, we studied the influence of the addition of curcumin and quercetin extracts in amounts of 2.5% and 5% to wheat flour (2.5:97.5; 5:95). The analysis of the rheological properties of dough was carried out using a Mixolab 2. A Rheofermentometer F4 was used to assess the dough's fermentation, and a Volscan was used to evaluate the baking trials. The effect of the extracts on the rheological properties of dough was measured and found to be statistically significant, with curcumin shortening both dough development time and dough stability. Doughs made with greater quantities of extract had a greater tendency to early starch retrogradation, which negatively affects the shelf life of the end products. The addition of extracts did not significantly affect either the ability to form gas during fermentation or its retention, which is important because this gas is prerequisite to forming a final product with the required volume and porosity of crumb. Less favourable results were found on sensory evaluation, wherein the trial bread was significantly worse than the control wheat bread. The panel's decision-making might have been influenced by the atypical colour of the bread made with additives, and in case of a trial bread made with quercetin, by a bitter taste. From the technological point of view, the results confirmed that the composite flours prepared with the addition of extracts of curcumin and quercetin in amounts of 2.5% and 5% can be processed according to standard procedures. The final product will be bread with improved nutritional profile and specific sensory properties, specifically an unconventional and attractive colour.

Complementary nutritional and health promoting constituents in germinated and probiotic fermented flours from cowpea, sorghum and orange fleshed sweet potato

Germination and fermentation are age-long food processes that beneficially improve food composition. Biological modulation by germination and probiotic fermentation of cowpea, sorghum, and orange-fleshed sweet potato (OFSP) and subsequent effects on the physicochemical (pH and total titratable acidity), nutritional, antinutritional factors and health-promoting constituents/properties (insoluble dietary fibres, total flavonoid and phenolic contents (TFC and TPC) and antioxidant capacity) of the derived flours were investigated in this study. The quantification of targeted compounds (organic acids and phenolic compounds) on an ultra-high performance liquid chromatography (UHPLC) system was also done. The whole cowpea and sorghum were germinated at 35 °C for 48 h. On the other hand, the milled whole grains and beans and OFSP were fermented using probiotic mesophilic culture at 35 °C for 48 h. Among the resultant bioprocessed flours, fermented sorghum and sweet potato (FSF and FSP) showed mild acidity, increased TPC, and improved ferric ion-reducing antioxidant power. While FSF had better slowly digestible and resistant starches and the lowest oxalate content, FSP indicated better hemicellulose, lowest fat, highest luteolin, caffeic and vanillic acids. Germinated cowpea flour exhibited reduced tannin, better lactic acid, the highest crude fibre, cellulose, lignin, protein, fumaric, L-ascorbic, trans-ferulic and sinapic acids. The comparable and complementary variations suggest the considerable influence of the substrate types, followed by the specific processing-based hydrolysis and biochemical transitions. Thus, compositing the bioprocessed flours based on the unique constituent features for developing functional products from climate-smart edibles may partly be the driver to ameliorating linked risk factors of cardiometabolic diseases.

Chemical profile, antioxidant and antimicrobial activity of Pinus heldreichii Christ. Distributed in Bulgaria

Pinus heldreichii Christ. (Bosnian pine), a Tertiary relict and Balkan sub-endemic, has not been comprehensively studied for its essential oil (EO) profile and bioactivity of its different plant parts. This study aimed to determine the EO yield, composition and antimicrobial activity from different parts of P. heldreichii at three different populations (mountains) in Bulgaria. Furthermore, the study assessed the antioxidant activities of plant tissue, including leaves (needles), twigs wood, male and female cones. The EOs yield from different plant parts ranged from 0.09 % (leaves) to 0.74 % (wood of twigs), with monoterpenes being the predominant class. Limonene, α-pinene, β-caryophyllene, germacrene D, β-pinene, and β-myrcene were detected in the EO extracted from all analyzed trees. However, these compounds were not found in the EO extracted from all plant parts of the same trees. Four chemical groups (chemotypes) were identified for EO from twigs, and three chemotypes were identified for EO from leaves. The chemotypes were based on the percent ratio of the main EO constituents (>5 %). Leaves tissue showed the highest values in terms of polyphenols and flavonoids, as well as higher ABTS radical scavenging activity, while the highest antimicrobial activity against Staphylococcus aureus subsp. aureus was seen in the EOs obtained from twigs. This is the first study to identify several chemotypes based on leaf and twigs EO of P. heldreichii distributed in Bulgarian flora. Furthermore, the EO of twigs tips (TT), male cones (MC), and wood of one-two-year-old twigs (WT) of the same trees were reported for the first time. The total polyphenol, flavonoid content, and radical scavenging activity of tissues of annual twigs wood and biennial twigs wood, leaf tissue, MC tissue, and the twigs tips tissue is also reported for the first time in the accessible literature. These findings highlight the potential of P. heldreichii to provide EOs with varying compositions and bioactivities, making them suitable for nutraceutical, pharmacological, and potentially food additive applications. Furthermore, the identification of chemotype accessions in this study suggests their selection for the development of new forest crop as a source for natural products with desirable composition and bioactivity.

Effects of in vitro fecal fermentation on the metabolism and antioxidant properties of cyanidin-3-O-glucoside

Anthocyanins' potential health benefits have garnered significant interest. However, due to low bioavailability, the gut microbiota-associated metabolites are suspected to mediate their bioactivity. In this study, cyanidin-3-glucoside (C3G) was fermented with fecal inoculum to simulate colonic microbiota interaction in vitro. The metabolites and antioxidant properties of pre- (P-C3G) and post-fermentation (F-C3G) were determined. Fermentation significantly increased contents of five metabolites (cyanidin, protocatechuic acid, phloroglucinaldehyde, 4-hydroxybenzoic acid and 4-hydroxyphenylacetic acid). Additionally, F-C3G demonstrated superior radicals scavenging than P-C3G, as well as to alleviate H2O2-induced damage in HepG2 cell via increasing superoxide dismutase by 43.26% and catalase by 39.83%, reducing malonaldehyde by 16.40% and cellular ROS production, and activating Nrf2 pathway. Moreover, F-C3G significantly extended the survival rate by 20.67% of Caenorhabditis elegans under heat stress by antioxidation in vivo. This study suggested that anthocyanins metabolism by gut microbiota produce specific metabolites, which potentially exerts protection.

Metabolomic profiling and quantification of polyphenols from leaves of seven Acacia species by UHPLC-QTOF-ESI-MS

The genus Acacia (Fabaceae) comprises >1350 species and has been used in traditional medicine as infusions and decoctions to treat wounds, sores, headaches, diarrhea, and cough. The leaf methanolic extracts of seven Acacia species growing in Egypt namely: Acacia saligna, Acacia seyal, Acacia xanthophloea, Acacia tortilis subsp. raddiana., Acacia tortilis, Acacia laeta, Acacia albida were analyzed using UPLC-QTOF-ESI-MS. A total of 37 polyphenols were identified and discussed in detail. They included phenolic acids, flavonoids, and procyanidins, among which sixteen polyphenols were identified in Acacia for the first time. Folin-ciocalteau assay and ferric reducing antioxidant power, cupric reducing antioxidant capacity, 2,20 -azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) cation radical and the scavenging capacity against 2,2-diphenyl-1- picrylhydrazyl radical were performed to investigate the total phenolic content and the antioxidant activity of the Acacia extracts, respectively. Furthermore, the absolute quantification of eighteen polyphenols common to most of the species was performed using UPLC-MS. It was evident that the differences in the chemical composition among the species accounted for the difference in antioxidant activity which was in line together with the total phenolic content.

Assessing the effect of Maillard reaction products on the functionality and antioxidant properties of Amaranth-red seaweed blends

Plant-based proteins, represented by amaranth in our study, embrace a potential as an ingredient for the functional-food formulation. However, their efficacy is hindered by inherent limitations in solubility, emulsification, and antioxidant traits. The Maillard reaction, a complex chemical-process resulting in a diverse array of products, including Maillard conjugates and Maillard reaction products (MRPs), can employ variable effects on these specific attributes. To elucidate the influence of this reaction and the MRPs on the aforementioned properties, we used a complex blend of dehydrated seaweed Gracilaria and amaranth protein to create a conjugate-MRP blend. Our investigations revealed that the resultant incorporation enhanced solubility, emulsification, and antioxidant properties, while the intermediates formed did not progress to advanced glycation stages. This change is likely attributed to the dual effect of conjugates that altered the secondary protein structure, while the generation and/or preservation of MRPs post ultrasonication and spray drying enhanced its antioxidant potential.

Tuning the mechanical properties of pectin films with polyphenol-rich plant extracts

The mechanical properties of pectin films enhanced with polyphenol-rich fruit extracts were investigated. The scavenging and reducing activity of plant extracts incorporated into the pectin films were determined using bench assays, and their antioxidant activity was correlated with a high presence of polyphenols, which were predominantly comprised of flavonoids and anthocyanins. The pectin films generated from the extracts exhibited a range of mechanical properties; tensile strength (4.99 MPa - 6.91 MPa), elongation at break (45.8 % - 52.3 %), and stiffness (1835 g mm-1 - 2765 g mm-1). To investigate the underlying relationships between plant extract composition and mechanical properties, Projection to Latent Structures (PLS) models were developed. The PLS models revealed that extracts containing high sugar and polyphenol content increase the tensile strength and moisture content of films. The elongation at break of the films was improved or diminished depending on the profile of sugar, acids, and polyphenols in the fruit extracts. Furthermore, the structures and concentration of anthocyanins and flavonoids were identified to strongly influenced the elongation at break differences. By modifying the concentration of sugars, organic acids, and polyphenols, the mechanical properties of pectin-based films can be tuned for tailored applications as food packaging materials.

Unveiling the Potent Antiviral and Antioxidant Activities of an Aqueous Extract from Caesalpinia mimosoides Lamk: Cheminformatics and Molecular Docking Approaches

Our group previously demonstrated that Caesalpinia mimosoides Lamk exhibits many profound biological properties, including anticancer, antibacterial, and antioxidant activities. However, its antiviral activity has not yet been investigated. Here, the aqueous extract of C. mimosoides was prepared from the aerial parts (leaves, stalks, and trunks) to see whether it exerts anti-influenza (H1N1) effects and to reduce the organic solvents consumed during extraction, making it a desirable approach for the large-scale production for medical uses. Our plant extract was quantified to contain 7 g of gallic acid (GA) per 100 g of a dry sample, as determined using HPLC analysis. It also exerts potent antioxidant activities comparable to those of authentic GA. According to untargeted metabolomics (UPLC-ESI(-)-QTOF-MS/MS) with the aid of cheminformatics tools (MetFrag (version 2.1), SIRIUS (version 5.8.3), CSI:FingerID (version 4.8), and CANOPUS), the major metabolite was best annotated as "gallic acid", phenolics (e.g., quinic acid, shikimic acid, and protocatechuic acid), sugar derivatives, and dicarboxylic acids were deduced from this plant species for the first time. The aqueous plant extract efficiently inhibited an influenza A (H1N1) virus infection of MDCK cells with an IC50 of 5.14 µg/mL. Of equal importance, hemolytic activity was absent for this plant extract, signifying its applicability as a safe antiviral agent. Molecular docking suggested that GA interacts with conserved residues (e.g., Arg152 and Asp151) located in the catalytic inner shell of the viral neuraminidase (NA), sharing the same pocket as those of anti-neuraminidase drugs, such as laninamivir and oseltamivir. Additionally, other metabolites were also found to potentially interact with the active site and the hydrophobic 430-cavity of the viral surface protein, suggesting a possibly synergistic effect of various phytochemicals. Therefore, the C. mimosoides aqueous extract may be a good candidate for coping with increasing influenza virus resistance to existing antivirals.

Bioactive Properties of Tagetes erecta Edible Flowers: Polyphenol and Antioxidant Characterization and Therapeutic Activity against Ovarian Tumoral Cells and Caenorhabditis elegans Tauopathy

Tagetes erecta is an edible flower deeply rooted in traditional Mexican culture. It holds a central role in the most popular and iconic Mexican celebration, "the Day of the Dead". Furthermore, it is currently receiving interest as a potential therapeutic agent, motivated mainly by its polyphenol content. The present study aims to evaluate the biological activity of an extract synthesized from the petals of the edible flower T. erecta. This extract showed significant antioxidant scores measured by the most common in vitro methodologies (FRAP, ABTS, and DPPH), with values of 1475.3 μM trolox/g extr, 1950.3 μM trolox/g extr, and 977.7 μM trolox/g extr, respectively. In addition, up to 36 individual polyphenols were identified by chromatography. Regarding the biomedical aspects of the petal extract, it exhibited antitumoral activity against ovarian carcinoma cells evaluated by the MTS assay, revealing a lower value of IC50 compared to other flower extracts. For example, the extract from T. erecta reported an IC50 value half as low as an extract from Rosa × hybrida and six times lower than another extract from Tulbaghia violacea. This antitumoral effect of T. erecta arises from the induction of the apoptotic process; thus, incubating ovarian carcinoma cells with the petal extract increased the rate of apoptotic cells measured by flow cytometry. Moreover, the extract also demonstrated efficacy as a therapeutic agent against tauopathy, a feature of Alzheimer's disease (AD) in the Caenorhabditis elegans experimental model. Treating worms with the experimental extract prevented disfunction in several motility parameters such as wavelength and swimming speed. Furthermore, the T. erecta petal extract prevented the release of Reactive Oxygen Species (ROS), which are associated with the progression of AD. Thus, treatment with the extract resulted in an approximate 20% reduction in ROS production. These findings suggest that these petals could serve as a suitable source of polyphenols for biomedical applications.

Effect of Milk Origin and Seasonality of Yogurt Acid Whey on Antioxidant Activity before and after In Vitro Gastrointestinal Digestion

Yogurt acid whey (YAW) is a by-product of Greek strained yogurt production. The disposal of YAW constitutes an environmental problem, and given the increasing demand of Greek yogurt worldwide, its handling is a challenge. However, whey-derived peptides, resulting from microbial fermentation as well as those resulting from further hydrolysis during the digestion process, have been linked to enhanced biological activities. In this study, the antioxidant capacity of 33 samples of YAW obtained from Greek dairy companies of bovine, ovine or caprine origin was investigated using both cell-free and cell-based assays. The YAW samples, their in vitro digestion products (YAW-Ds) and a fraction of the digests (less than 3 kDa; YAW-D-P3) were assessed using four biochemical assays, namely ORAC, ABTS, FRAP and P-FRAP. Our data revealed a higher antioxidant capacity for digested samples compared with undigested samples, with all four methods. ORAC values after in vitro digestion were higher for the ovine samples compared to their bovine (YAW-D and YAW-D-P3) and caprine (YAW-D-P3) counterparts. Furthermore, the YAW-D-P3 fraction derived from samples collected in the summer months exhibited higher ORAC values when compared to the respective fraction from the winter months' samples. The cellular antioxidant activity of ovine YAW-D-P3 was improved in H2O2-treated HT29 cells compared to the control H2O2-treated cells. However, YAW-D-P3 could not trigger either the pathways involving the transcription factors NF-κB or NFE2L2 or the gene expression of SOD1, CAT and HMOX1 in LPS-challenged THP-1-derived macrophages. These results suggest that YAW, and particularly YAW from ovine origin, could be used as a natural source for its antioxidant potential in human and animal nutrition.

Detection of gallic acid in food using an ultra-sensitive electrochemical sensor based on glass carbon electrode modified by bimetal doped carbon nanopolyhedras

Gallic acid is widely used as an antioxidant in food because of its good antioxidant function, but excessive intake induces side effects in humans, so it is essential to devise a highly responsive technique for detecting gallic acid. In this work, we synthesized ZIF-67@FePc by the one-pot method. The synthesized material is more stable at high temperatures compared to ZIF-67 and maintains its original morphology during pyrolysis, when iron was introduced as a second metal active site during the synthesis process. Subsequently, Co/FeOX@NC-800 was employed to fabricate a GA sensor on a GCE. The developed sensor exhibited remarkable sensitivity towards GA, featuring a low LOD of 1.30 nM and a linear range spanning from 5 to 4500 nM. The electrochemical sensors we have prepared also showed good selectivity, stability, and reproducibility. It has been successfully employed for detecting GA in actual samples such as apples, grapes, tomatoes, and red wine.

In Vitro Anti-Diabetic, Anti-Inflammatory, Antioxidant Activities and Toxicological Study of Optimized Psychotria malayana Jack Leaves Extract

Psychotria malayana Jack (Family: Rubiaceae, local name: Salung) is a traditional herb used to treat diabetes. A previous study by our research group demonstrated that P. malayana methanolic and water extract exhibits significant potential as an effective agent for managing diabetes. Further research has been performed on the extraction optimization of this plant to enhance its inhibitory activity against α-glucosidase, a key enzyme associated with diabetes, and to reduce its toxicity. The objectives of this study are to evaluate the anti-diabetic, anti-inflammatory, and antioxidant properties of the optimized P. malayana leaf extract (OE), to evaluate its toxicity using a zebrafish embryo/larvae model, and to analyze its metabolites. The anti-diabetic effects were assessed by investigating α-glucosidase inhibition (AGI), while the inflammation inhibitory activity was performed using the soybean lipoxygenase inhibitory (SLOXI) test. The assessment of antioxidant activity was performed utilizing FRAP and DPPH assays. The toxicology study was conducted using the zebrafish embryo/larvae (Danio rerio) model. The metabolites present in the extracts were analyzed using GC-MS and LC-MS. OE demonstrated significant AGI and SLOXI activities, represented as 2.02 and 4.92 µg/mL for IC50 values, respectively. It exhibited potent antioxidant activities as determined by IC50 values of 13.08 µg/mL (using the DPPH assay) and 95.44 mmol TE/mg DW (using the FRAP assay), and also demonstrated an LC50 value of 224.29 µg/mL, which surpasses its therapeutic index of 111.03. OE exhibited a higher therapeutic index compared to that of the methanol extract (13.84) stated in the previous state of the art. This suggests that OE exhibits a lower level of toxicity, making it safer for use, and has the potential to be highly effective in its anti-diabetic activity. Liquid chromatography-mass spectrometry (LC-MS) and gas chromatography-mass spectrometry (GC-MS) demonstrated the presence of several constituents in this extract. Among them, several compounds, such as propanoic acid, succinic acid, D-tagatose, myo-inositol, isorhamnetin, moracin M-3'-O-β-D-glucopyranoside, procyanidin B3, and leucopelargonidin, have been reported as possessing anti-diabetic and antioxidant activities. This finding offers great potential for future research in diabetes treatment.

Ultrasound-assisted extraction of bioactive pigments from Spirulina platensis in natural deep eutectic solvents

Spirulina platensis biopigments have been documented as a potential source of nutritional, physiological, and pharmacological purposes due to the presence of bioactive pigments, total phenolic content (TPC) and the consequent antioxidant activity that these compounds present. Bioextracts market has increased in the last decades and is a key option for replacing fossil-derived products and promote the transition for a bio-based economy. To take advantage of these compounds more effectively, optimized extraction processes must be researched and used in biomass sources. The present study focused on optimizing the ultrasound-assisted extraction (UAE) using response surface methodology. Three factor and three level Box-Behnken design was used to optimize the extraction of bioactive pigments, and to investigate the effects of three independent variables, x 1: extraction temperature (40-60 °C), x 2: extraction cycle time (20-40 min), and x 3: solvent-to-biomass ratio (50-70 mL/mg) on total pigment yield, antioxidant assay, and TPC (dependent variables). A second-order polynomial model was used for predicting the responses. Statistically, the model was validated using an analysis of variance. Results revealed that ultrasound-assisted temperature, time, and solvent-to-biomass ratio had a significant (p < 0.05) influence on the total pigment yield, while temperature and solvent-to-biomass ratio had a significant influence in the antioxidant activity, and temperature significantly influenced the total pigment yield. For total pigment yield, antioxidant activity, and total phenol content, theR 2 values of the models generated were 0.8627, 0.8460, and 0.9003, respectively, indicating that the models developed based on second-order polynomials were satisfactorily accurate for analyzing interactions between parameters. Desirability functions showed that the optimal extraction parameters were temperature: 60 °C, extraction cycle time: 20 min; and a solvent-to-biomass ratio of 70 mL/mg. Under optimal conditions, experimental values for total pigment yield, total phenol content expressed as gallic acid equivalent (GAE), and antioxidant activity expressed as Trolox equivalent (TRE) were: 165.19 ± 1.01 mg/g Dry Matter (DM), 36.50 ± 0.98 mg GAE/g DM, and 37.98 ± 0.58 mg TRE/g DM, respectively. The experimental values showed a good agreement with the predicted values with residual standard low 1% under optimum conditions. This optimized ultrasound-assisted method in natural eutectic solvents is effective and scalable to a green extraction of the bioactive pigments from Spirulina platensis with potential application to food, pharmaceutical, functional materials, and packaging.

Synthesis, biological evaluation, and computational studies of N-benzyl pyridinium-curcumin derivatives as potent AChE inhibitors with antioxidant activity

A library of N-benzylpyridinium-based compounds, 7a-j and 8a-j, was designed and synthesised as potential acetylcholinesterase) AChE (inhibitors. An in vitro assay for the synthesised compounds showed that most compounds had significant AChE inhibitory activities at the nanomolar and submicromolar levels. The benzyl (8a) and fluoro (8b) derivatives were the most active, with IC50 values ≤56 nM. Compound 7f, which had a benzyl moiety, showed the highest potency among all the target compounds, with an IC50 value of 7.5 ± 0.19 nM against AChE, which was higher than that of the activities of tacrine (IC50 = 30 ± 0.2 nM) and donepezil (IC50 = 14 ± 0.12 nM). Compounds with vanillin moieties exhibited antioxidant activity. Among the tested compounds, four derivatives (7f, 7 g, 8f, and 8 g) exhibited superior AChE inhibitory activity, with Ki values of 6-16 nM, which were potent in the same range as the approved drug, donepezil. These compounds showed moderate antioxidant activities, as indicated by the results of the ABTS assay.

Iron(II)-cyclopentadienyl compounds are cytotoxic against colon adenocarcinoma cell lines: Ethylenebis(diphenylphosphane) vs. triphenylphosphane

Structure-activity studies aiming to understand the role of each coligand in the formulation of new metallodrugs is an important subject. In that frame, six new compounds with general formula [Fe(η5-C5H5)(dppe)(L)][CF3SO3] with L = benzonitriles (1-4) or carbon monoxide (5) and compound [Fe(η5-C5H5)(CO)(PPh3)2][CF3SO3] (6) were synthesized and compared with three other previously reported compounds [Fe(η5-C5H5)(CO)(L)(PPh3)][CF3SO3]. We were particularly interested in assessing the effect of dppe vs. (PPh3 + CO) for this set of compounds. For that, all compounds were tested against two human colon adenocarcinoma cell lines, Colo205 and the refractile Colo320 (expressing ABCB1, an efflux pump causing multidrug resistance), showing IC50 values in the micromolar range. The presence of dppe in the compound's coordination sphere over (PPh3 + CO) allows for more redox stable compounds showing higher cytotoxicity and selectivity, with improved cytotoxicity towards resistant cells that is not related to the inhibition of ABCB1. Further studies with GSH and H2O2 for selected compounds indicated that their antioxidant ability is not probably the main responsible for their cytotoxicity.

Variations in Composition, Antioxidant Profile, and Physical Traits of Goat Milk within the Semi-Intensive Production System in Mountainous Areas during the Post-Weaning to End-of-Lactation Period

Dairy products from mountain-origin milk are known for their superior composition and quality. This study aimed to examine changes in composition, nutritional quality, and antioxidant properties of milk from semi-intensively managed goats in mountainous regions during the post-weaning to end-of-lactation period. Bulk tank milk samples from 10 farms were collected bi-weekly in the period from March to September. The farms were situated in regions with an average altitude of 772.20 m above sea level. The results revealed significant variations in milk composition, with fluctuations in fat, protein, lactose, and total solids. Milk yield per doe showed seasonal differences, with the highest yield in April and the lowest in September. Fatty acid composition exhibited changes throughout the sampling period, with variations in polyunsaturated fatty acids. Nutritional indices, such as the atherogenicity index and thrombogenicity index, remained within the recommended values. Antioxidant properties, including total phenolic content, DPPH, FRAP, and ABTS, showed significant differences, with higher values toward the end of the study. Milk pH, electrical conductivity, brix value, and refractive index also exhibited variations, while density and freezing point remained relatively stable. The study provided valuable information that can be used to develop breeding and feeding plans to achieve uniform milk quality in mountainous regions.