Recovery of natural polyphenols from spinach and orange by-products by pressure-driven membrane processes

Spinach and orange by-products are well recognized for their health benefits due to the presence of natural polyphenols with antioxidant activity. Therefore, the demand to produce functional products containing polyphenols recovered from vegetables and fruits has increased in the last decade. This work aims to use the integrated membrane process for the recovery of polyphenols from spinach and orange wastes, implemented on a laboratory scale. The clarification (microfiltration and ultrafiltration, i.e., MF and UF), pre-concentration (nanofiltration, NF), and concentration (reverse osmosis, RO) of the spinach and orange extracts were performed using membrane technology. Membrane experiments were carried out by collecting 1 mL of the permeate stream after increasing the flow rate in 1 mL/min steps. The separation and concentration factors were determined by HPLC-DAD in terms of total polyphenol content and by polyphenol families: hydroxybenzoic acids, hydroxycinnamic acids, and flavonoids. The results show that the transmembrane flux depended on the feed flow rate for MF, UF, NF, and RO techniques. For the spinach and orange matrices, MF (0.22 μm) could be used to remove suspended solids; UF membranes (30 kDa) for clarification; NF membranes (TFCS) to pre-concentrate; and RO membranes (XLE for spinach and BW30 for orange) to concentrate. A treatment sequence is proposed for the two extracts using a selective membrane train (UF, NF, and RO) to obtain polyphenol-rich streams for food, pharmaceutical, and cosmetic applications, and also to recover clean water streams

Recovery of natural polyphenols from spinach and orange by-products by pressure-driven membrane processes

Spinach and orange by-products are well recognized for their health benefits due to the presence of natural polyphenols with antioxidant activity. Therefore, the demand to produce functional products containing polyphenols recovered from vegetables and fruits has increased in the last decade. This work aims to use the integrated membrane process for the recovery of polyphenols from spinach and orange wastes, implemented on a laboratory scale. The clarification (microfiltration and ultrafiltration, i.e., MF and UF), pre-concentration (nanofiltration, NF), and concentration (reverse osmosis, RO) of the spinach and orange extracts were performed using membrane technology. Membrane experiments were carried out by collecting 1 mL of the permeate stream after increasing the flow rate in 1 mL/min steps. The separation and concentration factors were determined by HPLC-DAD in terms of total polyphenol content and by polyphenol families: hydroxybenzoic acids, hydroxycinnamic acids, and flavonoids. The results show that the transmembrane flux depended on the feed flow rate for MF, UF, NF, and RO techniques. For the spinach and orange matrices, MF (0.22 μm) could be used to remove suspended solids; UF membranes (30 kDa) for clarification; NF membranes (TFCS) to pre-concentrate; and RO membranes (XLE for spinach and BW30 for orange) to concentrate. A treatment sequence is proposed for the two extracts using a selective membrane train (UF, NF, and RO) to obtain polyphenol-rich streams for food, pharmaceutical, and cosmetic applications, and also to recover clean water streams

Estudio de la composición fitoquímica de la oleorresina de aji rocoto (Capsicum pubescens) procedente de el Valle de Tumbaco

The main objective of this investigation was to identify and quantify dihydrocapsaicin as the main chemical compound contained in the oleoresin of the Capsicum pubescens species. This species collected from four populations in El Valle de Tumbaco in Quito. Dihydrocapsaicin identifying oleoresin was done by Thin Layer Chromatography (TLC). These (oleoresins and capsaicinoids) were then compared with the standard of dihydrocapsaicin 98% purity. As for fluorescence, the presence dihydrocapsaicin was mild a wavelength of 254nm. The quantification of capsaicin was using High Performance Liquid Chromatography (HPLC). The samples of Puembo´s and Quinche´s location, presented the highest performance with an average of 20.63 mg/kg. Phytochemical show screening was performed mainly oleoresins finding: alkaloids, oils and fats, resins, phenolics, tannins, reducing sugars, saponins and bitter principles. According to the soil´s analysis of the four locations, Puembo and El Quinche contain higher amounts of phosphorus (P) and iron (Fe) than Pifo and Tumbaco, what it could mean increased production of this secondary metabolite.El objetivo del presente trabajo de investigación, fue identificar y cuantificar la dihidrocapsaicina contenida en la oleorresina de la especie Capsicum pubescens, colectada en cultivos de cuatro poblaciones de El Valle de Tumbaco en Quito. Se realizó la identificación y cuantificación de este compuesto mediante cromatografía en capa fina (TLC) y cromatografía líquida de alta resolución (HPLC) respectivamente, tanto en las oleorresinas como en solución extractiva utilizando estándar de dihidrocapsaicina de 98% de pureza, y como medio de detección a la radiación UV a una longitud de onda de 254nm. Las muestras colectadas en las localidades de Puembo y El Quinche, presentaron mayor concentración de dihidrocapsaicina con un promedio de 20,63mg/kg. Se realizó el tamizaje fitoquímico de las oleorresinas encontrando principalmente: alcaloides, aceites y grasas, resinas, compuestos fenólicos, taninos, azúcares reductores, saponinas y principios amargos. Se analizó muestras de suelo del lugar de recolección del material vegetal encontrando que los suelos de cultivo de esta especie en Puembo y El Quinche contienen mayores cantidades de fósforo (P) y hierro (Fe) que los suelos de cultivo de Pifo y Tumbaco lo que podría suponer la mayor producción de este metabolito secundario