The industrialization of potato and tomato produces large amount of wastes. Previous studies have demonstrated that these by-products are rich in antioxidant compounds. In this study, the composition and antioxidant efficacy of extracts from potato and tomato by-products were determined in order to evaluate their potential as food additives. Potato and tomato wastes showed to be good sources of fiber, protein and antioxidants. The antioxidant activity and total phenolic, carotenoid and lycopene contents were determined in methanol, ethanol and acetone extracts of the residues. Methanol was the best solvent for the extraction of phenolics while acetone was the best in the extraction of carotenoids in both residues. The greatest antioxidant activity (14.10 μmol Trolox/g) resulted when potato peels were extracted with ethanol. The oxidative stability of canola oil containing either ethanol extracts of potato and tomato wastes (200 and 400 mg/kg) or the synthetic antioxidant BHT (200 mg/kg), compared to oil without antioxidants, was evaluated by measuring their peroxide values, conjugated dienes and p-anisidine value after 72 and 144 h storage at 65 °C. The order of antioxidant efficacy was as follows: potato peels > BHT > tomato residues. The results showed that ethanol extracts of potato and tomato waste could be used as natural antioxidant additives in the protection of vegetable oils.

El tratamiento de residuos peligrosos que contienen acetonitrilo (ACN), generados por el uso de técnicas instrumentales como la cromatografía de líquidos de alta resolución son un desafío ambiental y económico para los laboratorios analíticos, este trabajo propone alternativas para reducir la dificultad en su manejo y los costos asociados a su disposición final. Se analizaron muestras provenientes de tres diferentes laboratorios analíticos que contenían distintas concentraciones de ACN, los tratamientos aplicados a dichas muestras fueron: hidrólisis ácida (H2SO4 concentrado), hidrólisis básica (NaOH al 40% m/v) y oxidación con ozono. El acetonitrilo se cuantificó mediante una adecuación al procedimiento analítico para disolventes residuales clase 1 y clase 2 capítulo Solventes Residuales de la USP vigente. En todas las muestras se observó una reducción >80% de ACN utilizando cualquiera de los tres tratamientos independientemente de su concentración inicial, la hidrólisis básica parece representar la mejor opción de frente a las demás, sin embargo, se determinó que la opción viable es la oxidación con ozono, ya que tiene mayores ventajas que incluyen: un costo menor, esto implica que si el proceso se lleva a una escala mayor se prescinde del empleo de tanques de oxígeno ya que este se tomaría del aire atmosférico, es un método más seguro ya que no involucra factores como la generación de calor, aunado a evitar el uso de reactivos potencialmente peligrosos, pero principalmente es un proceso de tratamiento amigable con el medio ambiente, ya que no genera nuevos residuos.

Grape pomace (GP), a major wine industry residue, contains substantial amounts of phenolic bioactive compounds whose valorization potential remains underexploited. In this study, pomaces from the Syrah, Malbec, Cabernet Sauvignon, Tempranillo, Nebbiolo-Sangiovese (blend), Cabernet Franc, Merlot, and Ensamble varieties were characterized in terms of total phenolic content (TPC), flavonoids, anthocyanins, tannins, and antioxidant capacity. Grape pomace flour (GPF) was obtained by drying, milling, and sieving (<250 µm) GP at 60 °C, and its functional properties were compared with GP and two commercial pomace flours (H1 and H2). The GPFs had a TPC of 3.48–12.06 mg gallic acid equivalents g⁻¹ dry basis (d.b.), flavonoid content of 11.78–71.65 mg quercetin equivalents g⁻¹ d.b., anthocyanin content of 41.46–291.85 mg cyanidin-3-glucoside equivalents g⁻¹ d.b., tannin content of 18.85–45.98 mg (+)-catechin equivalents g⁻¹ d.b., and antioxidant capacity of 304.2–768.3 μmol Trolox equivalents g⁻¹ d.b. The Malbec variety exhibited the best bioactive profile and was incorporated into a gelatin-based gummy matrix. Color and bioactive compound stability were measured over 30 days of storage at 40 °C and compared with a commercial flour (H1). The valorization of GP through drying and milling is a viable strategy for obtaining a flour with potential as a functional ingredient due to its bioactive composition and as a natural colorant in the food industry.

Indigo Blue dye is widely used in the textile industry for the dyeing of various garments, making it a frequent pollutant in textile effluents, being necessary to implement processes for its removal. For the study of photolytic degradation, a low-pressure mercury lamp (16 W) was employed. After exposing the dye in an aqueous solution at 30 mg/L for 3 days in a 6 L adapted bubbling column, no appreciable degradation was observed, which may be attributable to stabilizing compounds in the commercial dye that improve light fastness. For ozonolysis degradation, a medical-grade ozone generator was employed, which allows regulation of pure oxygen flow and ozone concentration; flow rates of 1/16 L/min (95 mg/L), 1/2 L/min (35 mg/L) and 3/4 L/min (26.2 mg/L) were applied for variable times. Each flow rate was injected into a 60 mL column containing variable dye concentrations between 210 and 1,100 mg/L, the residual ozone was carried into the ozone destructor incorporated in the ozone generator. It was observed that, regardless of the flow rate, reaction time and dye concentration utilized, while the dye/ozone ratio [mg/mg] is between 1.244 and 3.573, the decolorization efficiency ranges from 88.46 to 96.94% and the COD removal efficiency varies between 46.30 and 54.46% (with minor exceptions). When the dye/ ozone ratio is at least double, the decolorization efficiency decreases slightly, but the COD removal efficiency drops to 15.63%. Furthermore, analysis of dye concentration revealed a COD removal efficiency of 64.43% at a ratio of 1.427 mg/mg with a concentration of 1,168.29 mg/L.

The massive influx of Sargassum spp. into the Caribbean represents a major environmental, social and economic problem. In 2022, more than 24 million tons were recorded in the Atlantic, causing adverse impacts on tourism, coastal erosion, greenhouse gas emissions, the introduction of invasive species and high removal costs. Among the proposed mitigation strategies is the use of sargasso biomass as an agricultural substrate. The aim of this study was to valorize Sargassum spp. by employing it as a substrate for the cultivation of commercially relevant mushrooms and to assess its productive performance. Five gourmet species (Ganoderma lucidum, Hericium erinaceus, Pleurotus citrinopileatus, Pleurotus djamor and Trametes versicolor) were cultivated in triplicate solid-state fermentation under darkness at 26°C and 80-90% relative humidity, using Sargassum as the test substrate and straw as the control. Both substrates were subject pretreated and physicochemical characterization prior to inoculation. Sargassum exhibited a moisture retention capacity of 244%, an initial salinity of 1.002 °Baumé (°Bé) after the first wash (reduced to zero from the second wash onward and a pH of 5.9. Mycelial growth was observed in all species evaluated; however, only P. djamor completed fruiting. On Sargassum this species achieved higher biological efficiency (62.8%), productivity (1.1 days) and biodegradation rate (74%) compared to straw. It is concluded that Sargassum spp. is a suitable substrate for the cultivation of P. djamor, shortening production time and demonstrating high potential for the biological transformation of this marine residue into value-added fungal biomass.