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In this study we carried out the analysis of three varieties of unifloral honey of acacia (Robinia pseudoacacia), chestnut (Castanea sativa) and sulla (Hedysarum coronarium), in order to assess physicochemical and biochemical parameters, nutraucetical properties and antioxidant capacities. The three different varieties of unifloral honey showed clear differences in some parameters, such as the concentration of polyphenols, flavonoids, mineral elements, as well as different profiles of volatile molecules. These parameters allow differentiating the three varieties of unifloral honey investigated. The different concentration of polyphenols and flavonoids, the profile of volatile compounds and the presence of different concentration of some mineral elements allow discriminating different varieties of honey, and could be used as markers of product traceability. Moreover, the high concentration of some macro elements such as potassium, remarkably high in the chestnut honey, makes it especially useful in individuals with deficiency of these mineral or practicing sports.

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In this work, we intended to inhibit the biofilm synthesis and the metabolism of Gram-positive and Gram-negative bacteria using two highly available wastes (stem and marc) obtained after the manufacturing of Torrontes wine at Cafayate, Argentina. Wine wastes contain a significant amount of bioactive compounds, mainly phenolic compounds, which makes them a potential source of compounds with beneficial properties to human health, as they could inhibit the virulence of pathogenic bacteria or protect the tissue against oxidative stress. Marc and stem extracts of Torrontes wine were evaluated for their ability to inhibit the metabolism and biofilm production of Pseudomonas aeruginosa and Staphylococcus aureus strains. The phytochemical composition and antioxidant activity of these extracts were also determined. The methanol and ethyl acetate extracts, which contained the highest amount of total polyphenolic, exhibited the highest scavenging capacity of ABTS and nitric oxide and the strongest Fe3+ reducing power and exhibited the highest level of inhibition of the biofilm formation and of the metabolic activity in bacterial biofilm. We also noticed a positive correlation between phenolic compounds content, the antioxidant activity, and the anti-biofilm capacity of the winemaking wastes. These results display the potentiality of wine wastes to prevent or reduce the formation of biofilm. Moreover, their abundance makes them an attractive and affordable source of antibiofilm and antioxidant agents.

Staphylococcus aureus es un patógeno conocido que forma biopelículas en una amplia variedad de entornos y representa un riesgo severo de contaminación de los alimentos. El presente estudio se centró en la determinación de las capacidades antibiofilm de extractos de orujo procedentes de diferentes varietales de diferentes polaridades, procedentes de Cafayate, Argentina, frente a dos cepas de S. aureus. Se utilizaron orujos de tres varietales regionales (Bonarda, Tannat y Malbec) para inhibir la formación de biofilm (BF) o tratar una biopelícula formada. Se realizaron extracciones con solventes de polaridad creciente (cloroformo, acetato de etilo y etanol) y se enfrentaron 10 y 100 µg/mL de extractos a las cepas de S. aureus ATCC 6538 y LVP63. Los extractos acetato de etilo y etanólicos de orujo del varietal Tannat fueron los más efectivos para disminuir la formación de BF en S. aureus sin afectar el crecimiento planctónico. Respecto a los efectos sobre la biopelícula preformada, los extractos de los varietales Malbec y Tannat disminuyeron la actividad metabólica hasta un 70% y los extractos polares de Tannat y la mezcla de orujos disgregaron hasta un 65% el BF preformado por ambas cepas S. aureus. Por lo tanto, la reutilización de estos desechos agroindustriales se plantea como una alternativa natural para combatir bacterias patógenas en la industria alimentaria, disminuyendo el impacto de estos residuos agroindustriales en el ambiente y convirtiendo a estos desechos en un bioproducto, económicamente, rentable.