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.