Orange juice (OJ) contains a wide range of micronutrients and phytochemicals that have been found to exhibit preventive effects against the onset of several diseases. Moreover, alcoholic fermentation improves its content of bioactive antioxidant compounds. Thus, fermented orange juice (FOJ) with organic honey was finally investigated to obtain a demi-sec wine (dSW) and sec wine (SW). Sauro Giannini carried out this process at Cantina CITRO. Oxidative stress is responsible for the onset and progression of many chronic pathologies, including neurodegenerative diseases, cardiovascular diseases, cancer, diabetes, and obesity.

Thus, this study aimed to assess the antioxidant capacity of these new organic products to provide scientific evidence of their possible health benefits.

Using colorimetric assays, ferric reducing antioxidant power (FRAP) and ABTS radical scavenging activity (ARSA) were tested to provide information about the global antioxidant capacity. Moreover, the content of total polyphenols was evaluated. In addition, two principal polyphenols (tyrosol and hydroxytyrosol) were quantified by means of mass spectroscopy. Also, melatonin and its precursor tryptophan were quantified.

Although FOJ showed the best antioxidant capacity (FRAP: +24.30%; ARSA: +18.40%), SW increased the antioxidant activity (FRAP: +17.30%; ARSA: +6.20%), followed by dSW (FRAP: +16.60%; ARSA: +0.5%). This increase correlated positively with the polyphenol content (vs. FRAP: r = +0.872; vs. ABTS radical: r = −0.945). When polyphenols were quantified, both wines showed an increase in tyrosol (SW: 10.33 ng/mL; dSW: 12.57 ng/mL) and hydroxytyrosol (SW and dSW: 0.02 ng/mL) compared to the OJ. Finally, the fermentation consumed the tryptophan to synthesize the melatonin, whose values were maintained in both wines (≈ 20ng/mL). Melatonin is a ubiquitous molecule that is involved in numerous biological functions and is a well-known potent scavenger of reactive oxygen species.

In conclusion, these new wines from organic honey-fermented orange juice possess antioxidant capacity.

Beer, a widely consumed carbonated beverage, is made from malted cereal, hops, yeast, and water. Rich in carbohydrates, minerals, vitamins, amino acids, and polyphenols, it provides essential nutrients [1]. However, the brewing process generates significant solid waste, including hot trub, a slurry of wort, hop particles, and coagulated proteins formed during wort boiling [2]. Given the environmental impact of agro-industrial waste, sustainable methods to repurpose these by-products into bio-products are essential. The aim of this study was to evaluate the potential of transforming these by-products into biologically active extracts suitable for use as functional ingredients in cosmetic and pharmacological formulations. The prepared extracts included one alcoholic and one hydroalcoholic extract obtained through Soxhlet extraction, as well as a hydroalcoholic extract prepared via maceration. Antioxidant activity was assessed using the DPPH radical scavenging assay and the ferric reducing antioxidant power (FRAP) method. Additionally, the extracts were analysed for total flavonoid content using the aluminium chloride colorimetric method and total phenolic content using the Folin–Ciocalteu method. The results demonstrated that the different extracts exhibited antioxidant activity, with the alcoholic extract showing the best performance in both methods, obtaining a value of 61.31±0.39 mmol FeSO₄/g extract for the FRAP assay and a value of 11.74±0.57 mmol TE/g extract for the DPPH assay. Furthermore, the alcoholic extract displayed the highest levels of total phenolic content (3.66±0.17 mg GAE/g extract) and total flavonoid content (22.61±2.68 mg QE/g extract). These findings suggest that beer wastes could serve as a promising source of natural polyphenolic compounds, offering potential as an eco-friendly antioxidant ingredient. Such compounds could be incorporated into nutraceutical formulations or applied in pharmaceuticals and cosmetics, contributing to waste valorisation and sustainability.

1. Costa, Senna et al. (2021). DOI:10.1007/s12649-020-01163-6
2. Thiago, R. et al. (2014) DOI:10.5897/JBD2014.0043

Beer is a widely consumed carbonated beverage produced using natural ingredients such as malted cereals, hops, yeast, and water.¹ During the brewing process, large quantities of Brewers' Spent Grain (BSG), derived from barley malt, represent the residue left after wort extraction and before fermentation. Traditionally regarded as waste, BSG has primarily been used for applications such as animal feed, organic fertiliser, or brick production².

This study aims to evaluate the development of flour from BSG and assess its antioxidant properties to determine its functional benefits as a strategy to valorise this by-product, with potential applications in the food and nutraceutical industries. BSG samples were collected from the brewery Crafters (Sintra, Portugal) after the brewing process. The collected BSG was refrigerated and then dried in an oven with forced air circulation at 50°C, milled into flour, and sieved through a 400 µm mesh. The flour was subsequently packed, sealed in polyethylene bags to prevent exposure to oxygen, and stored at -20°C, away from light, until analysis. The antioxidant activity of the resulting BSG flour was evaluated using the DPPH radical scavenging assay and the ferric reducing antioxidant power (FRAP) method. The flour was analysed for total flavonoid and phenolic contents using the Folin–Ciocalteu method. The results showed that BSG flour has an antioxidant activity of 2.12 ± 0.37 µmol TE/g flour for the FRAP assay and 1.69 ± 0.16 µmol TE/g flour for the DPPH assay, with significant levels of total phenolics (1.27 ± 0.03 mg GAE/g flour) and flavonoids (3.05 ± 0.54 mg QE/g flour). These results highlight the potential of BSG as a valuable source of natural polyphenolic compounds. The developed flour could be used as an eco-friendly antioxidant ingredient with applications in the food and nutraceutical industries, improving product preservation and functional properties.

1. Senna Costa, F. et al. (2021). DOI: 10.1007/s12649-020-01163-6

2. Chetrariu, A., Dabija, A. (2023). DOI: 10.3390/foods12071533

Oxidative stress is a major factor in the development of diseases in Apis Mellifera. To assess the functionality of the antioxidant system in bees, total antioxidant status (TAS) serves as a critical indicator. Commonly, Vitamin C is used to enhance TAS, yet its effectiveness is limited by its relatively low antioxidant activity. In this study, we synthesized tris[N-(prop-2-en-1-yl)hydrazinecarbothioamide]cobalt(III) chloride, offering a novel alternative to Vitamin C for TAS enhancement. Notably, previous research has not explored coordination compounds for this purpose in bees.

The cobalt(III) complex was synthesized through the reaction of cobalt(II) hexahydrate with N-(prop-2-en-1-yl)hydrazinecarbothioamide in ethanol and hydrochloric acid at 50-55°C, yielding an octahedral complex cation, where the neutral bidentate ligands facilitated the oxidation of cobalt(II) to cobalt(III) with 87% efficiency. The characterization techniques included single crystal X-ray diffraction, FT-IR, ¹H NMR, ¹³C NMR, elemental analysis, and molar conductivity. Antioxidant activity was assessed via ABTS, DPPH, and ORAC assays, while toxicity was evaluated using Daphnia magna. The complex demonstrated significant antioxidant activity, with an IC₅₀ of 7.3±0.3 µM, and lower toxicity than expected, with an LC₅₀ of 56.3±3.1 µM.

The experimental results revealed that tris[N-(prop-2-en-1-yl)hydrazinecarbothioamide]cobalt(III) chloride increased TAS in the hemolymph of bees and larvae by up to 5 and 8 times, respectively. The IC₅₀ values were recorded at 2.5 mg/mL for bee hemolymph and 1.3 mg/mL for larval hemolymph, compared to control values of 13.6 mg/mL and 10.0 mg/mL, respectively.

The stimulatory effect of the tested compound on TAS surpassed the activity of Vitamin C by up to 5 times.

These findings suggest that increasing TAS levels in bees could enhance their immune systems, highlighting the potential of tris[N-(prop-2-en-1-yl)hydrazinecarbothioamide]cobalt(III) chloride as a beneficial additive in apicultural health practices.

This research was funded by the subprograms 010602 and 010701.

Many plant-derived compounds with high antioxidant activity are widely used in food applications. Among various methods for measuring antioxidant activity, such as FRAP, ORAC, ABTS, and ESR, DPPH (2,2-diphenyl-1-picrylhydrazyl) is the most commonly employed, despite the difficulties in comparing the results obtained with different DPPH concentrations across assays. To address this difficulty, Sherer and Godoy (2009) proposed using a new indicator, the Antioxidant Activity Index (AAI), calculated as the initial DPPH concentration divided by the EC50, accounting for the variation in the aforesaid DPPH concentration. In this study, we aimed to isolate and quantify antioxidant compounds from fruits and vegetables and compare them to known standards using the AAI index. For this purpose, extracts were prepared at 37°C using 1% HCl in ethanol. Samples were analyzed in triplicate, determining EC50 (ppm of dry sample needed to reduce the initial 50 ppm DPPH concentration by 50%) and calculating the Antioxidant Activity Index (AAI) as a ratio of the initial DPPH concentration to the EC50. AAI was assessed in extracts from various fruits, including grapes, apples, figs, peaches, plums, pears, and berries, along with standards such as gallic acid, ascorbic acid, ferulic acid, rutin, chlorogenic acid, and caffeic acid. Plums exhibited the highest AAI (1.06), followed by berries, with calafate (1.04) and maqui (0.96) standing out. Red grapes had an AAI of 0.59, apples and pears had lower values (0.33 and 0.29), and figs had the lowest (0.08). Standards showed significantly higher AAI values, ranging from 29.9 (gallic acid) to 6.23 (ferulic acid). These results suggest that these fruit and vegetable matrices could serve as sources of antioxidant compounds, adding value to local production and contributing to developing functional foods with health benefits beyond traditional nutritional requirements. Finally, we regard the usage of the AAI index as helpful when comparing results among assays and matrices.

Urtica dioica is a medicinal plant widely recognized for its therapeutic potential, particularly due to its potent antioxidant and anti-inflammatory properties. It has been traditionally used in various cultures for managing inflammatory disorders, metabolic syndromes, and neurodegenerative diseases. The plant’s pharmacological significance is largely attributed to its rich composition of bioactive compounds, including flavonoids, phenolic acids, and terpenoids, which contribute to its diverse biological activities.

The phytochemical composition of Urtica dioica extract was analyzed to determine its total phenolic and flavonoid content. Antioxidant activity was assessed using radical scavenging assays, ferric reducing antioxidant power (FRAP), ABTS•+ activity, and β-carotene bleaching inhibition. Pharmacokinetic properties were predicted in silico, evaluating drug-likeness based on Lipinski’s rule of five, gastrointestinal absorption, blood–brain barrier (BBB) permeability, interactions with P-glycoprotein (P-gp), and the inhibition of cytochrome P450 (CYP) isoforms.

Phytochemical analysis confirmed the presence of bioactive compounds contributing to the extract’s strong antioxidant potential, as demonstrated by its high radical scavenging capacity and inhibition of oxidative damage. Pharmacokinetic modeling indicated that the identified compounds exhibited good oral bioavailability, high gastrointestinal absorption, and the ability to cross the BBB, suggesting potential neuroprotective effects. Furthermore, none of the major compounds were substrates for P-gp, and they exhibited minimal inhibition of CYP isoforms, indicating a low risk of drug resistance and interactions.

Urtica dioica demonstrates promising pharmacological potential due to its antioxidant efficacy, favorable pharmacokinetic profile, and neuroprotective properties. These findings support its therapeutic application in oxidative stress-related disorders, including neurodegeneration and chronic inflammation. Further clinical studies are warranted to validate these results and explore its integration into pharmaceutical and nutraceutical formulations.

Macroalgae are a great source of antioxidants, which show valuable pharmacological properties and benefit human health [1]. The growing interest in marine algae is driven by their plentiful natural bioactive compounds, with biological benefits such as antioxidative, anti-inflammatory, antimicrobial, anticancer, and cardioprotective properties [2], which hold promise for the food and pharmaceutical industries [3,4]. The macroalgae species Fucus vesiculosus, Asparagopsis armata, Saccorhiza polyschides, and Stigeoclonium subsecundum were studied. The F. vesiculosus species represents a rich source of compounds such as polyphenols, and one particular group of polyphenols found in these brown algae are phlorotannins, which have a wide range of biological activities such as antibacterial, antioxidant, anti-tumor, anti-inflammatory, and anti-allergic activities [5]. The extracts were evaluated concerning their antioxidant activity, phenol concentration and antimicrobial activity. The results of the total phenol and antioxidant assays showed that Fucus vesiculosus extracted with acetone and water had the highest content of both total phenols and antioxidants. Additionally, we also evaluated how the Fourier Transform Infrared Spectroscopy (FTIR) spectra of the extracts could be correlated with their antioxidant properties. The results of FTIR showed that some of the species at specific concentrations had very similar chemistry properties after the analysis of their spectra, with the results of Partial Least Squares (PLS) indicating good correlation between the solvent and extract variables. Based on different solvents, it is possible to improve the extraction of the most suitable antioxidant compounds and consequently to develop a faster and more efficient model for analyzing their respective biomolecular effects, as well as classification models associated with machine learning techniques to save time and resources.

Essential oils are derived from aromatic plants and can be extracted from various parts, including flowers, leaves, bark, fruit, seeds, and other important parts of the plant. Historically, these oils have been utilized for their therapeutic properties and continue to be an integral part of folk medicine across diverse cultures, owing to their multifaceted and remarkable medicinal benefits, which encompass antioxidant, anti-inflammatory, analgesic, anti-cancer, liver-protective, and neuroprotective properties, among others. As part of the “Albread” project, supported by the Promove 2023 competition and titled “Aromatic plants from Alentejo, probiotics, and acorn flour in the development of functional bread”, this study aimed to investigate the antioxidant potential of essential oils marketed by companies in the Alentejo and Algarve regions of Portugal. A total of 21 essential oils were evaluated for their antioxidant capacity using two widely used methodologies: DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging and ABTS (2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) radical scavenging assays. The solvent employed for diluting the essential oils in this study was 70% ethanol, with Trolox serving as the standard, and all tests were conducted in triplicate. The results indicated a successful differentiation of the antioxidant potential of the essential oils across both methodologies. The DPPH method revealed antioxidant activity ranging from 0.039 to 0.518 mgTE/gEOW, while the ABTS method demonstrated a range of 0.21 to 3.08 mgTE/gEOW. It can be concluded that the 21 essential oils assessed from Portuguese companies exhibited variability in their antioxidant potential but maintained comparable patterns between the DPPH and ABTS methods. Essential oils 11, 12, and 13 exhibited the highest antioxidant activity, whereas oil 7 demonstrated the lowest potential.

Phenolic compounds (PCs) derived from plant sources have been increasingly studied in recent decades for their potent antioxidant capacities, which relate to their application in health, food, cosmetics, and other industries. Particularly, grape pomace is a well-recognized rich and sustainable source of PCs, especially flavanols, of which their content of flavan-3-ols (or tannins) are particularly high. To maximize the yields of extraction of these PCs from grape pomace, various optimizations approaches have been made, especially regarding conventional methods such as heat-assisted extraction (HAE), Soxhlet, andenzyme-assisted extraction (EAE), but also on more modern and sustainable technologies. The latter include ultrasound (UAE) and microwave-assisted extraction (MAE), pressurized liquid extraction (PLE), and pulse-electric fields (PEFs), among others. For instance, Merlot pomace has been reported to achieve yields of 65 mg gallic acid equivalents (GAE)/g dry extract (de) by HAE, 49 mg GAE/de by UAE, or 71 mg GAE/de by MAE. However, the effectiveness of an extraction method is not only measured in yield, but also in time, the use of solvents, and extraction yield, of which MAE, UAE, and other sustainable techniques stand out. Various parameters affect the extraction yield and PC composition, depending on the extraction method, i.e., temperature, time, solvent proportion, solvent choice, or method-inherent parameters, such as power or pressure. Moreover, grape variety has significance in PC composition and concentration. Considering these facts, an in-depth assessment of the optimum methods focusing on the yield of PCs from grape pomace should also consider the diversity of each grape's variety and origin. This work will present updated information onthe maximum yields achieved for grape pomace PCs (focusing on anthocyanins, resveratrol, and flavanols), and provide a comprehensive vision regarding the weight and effect of each method and their intrinsic parameters in PC extraction yields.

Lantana camara, which is used in Indian traditional medicine, was analysed to determine its phytochemicals and biological activities. The leaves were dried (250 g) and subjected to maceration and Soxhlet extraction techniques, employing solvents of increasing polarity. Chemical profiling was carried out using GC-MS, and the concentration of phenolics, flavonoids, alkaloids, and other bioactive compounds were determined using UV spectrophotometry. Preliminary phytochemical tests also indicated the existence of these compounds in considerable quantities, therefore recommending their utilization in treatments. Antioxidant activity was determined using DPPH, FRAP, ABTS, phosphomolybdate, H₂O₂, ^•OH, nitric oxide, and Fe²⁺-chelating methods. The extracts had a relatively high antioxidant capacity, which decreased the oxidative damage at 50, 100, 150, 200, and 250 µg/mL. Antidiabetic activity was confirmed by testing for α-amylase inhibition using starch azure as a substrate. The inhibition profile was assessed at 595 nm, indicating that inhibition was dependent on the extract concentrations (10-100 µg/mL). The antibacterial activity of the extract was assessed using the agar well diffusion method, showing activity against Escherichia coli, Bacillus subtilis, Staphylococcus aureus, and Klebsiella pneumonia. The presence of antifungal activity against bacterial types such as Candida albicans, Aspergillus niger, Aspergillus flavus, and Aspergillus fumigatus showed that the plant has antifungal properties supported by its high-spectrum antimicrobial property. The molecular docking analytical results showed high-affinity interactions between the bioactive compound and the target protein, which further validated the plant's antioxidant and antimicrobial potential. Based on these outcomes, it seems that Lantana camara extracts have potential for utilization in the pharmaceutical and nutraceutical industries as natural antioxidants and antidiabetic and antimicrobial compounds. More research has to be carried out on their toxicity, medical uses, and other forms of extraction methods in order to increase efficacy and minimize toxicities.