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RESUMEN : La explotación comercial del cacao, genera un volumen de residuos que puede utilizarse para la obtención de compuestos antioxidantes, entre otros usos. La cascarilla de cacao (tegu-mento), contiene un 23,3±0,4 mg GAE g-1, bajo la metodología estándar de extracción de polifenoles totales. Éste residuo fue seleccionado para desarrollar un protocolo de extracción asistido por enzimas, donde se evaluó celulasa, pectinasa y una mezcla de ambas enzimas en diferentes concentraciones (25-75 U mL-1). Otras variables como concentración de sustrato, pH y tiempo de reacción fueron evaluadas, mediante un diseño central compuesto. La celulasa en una concentración de 75 U mL-1, un pH de 6,6; una concentración de cascarilla de 185 g L-1 y un tiempo de reacción de 100 min, fueron las condiciones óptimas para obtener un extracto rico en polifenoles totales de 1,88 mg GAE mL-1, el cual fue validado posteriormente, obteniéndose una concentración de 1,527±0,013 mg GAE mL-1. ABSTRACT : Commercial exploitation of cocoa generates a volume of waste material that can be used to obtain antioxidant compounds, among others; Cocoa husk (tegument) contains 23.3±0.4 mg GAE g-1 under the standard methodology of total polyphenol extraction. This residue was selected to develop an extraction protocol assisted by enzymes, where cellulase, pectinase, and a mixture of both enzymes at different concentrations (25-75 U mL-1) were evaluated. Other variables such as substrate concentration, pH and reaction time were assessed by using a central composite design. The cellulase in a concentration of 75 U mL-1, pH 6.6, a husk concentration of 185 g L-1 and a reaction time of 100 min, were the optimal conditions to obtain an extract rich in polyphenols of 1.88 mg GAE mL-1, which was subsequently validated giving a concentration of 1.527±0.013 mg GAE mL-1. COL0066991

Biologically active compounds although being native constituents of food, are not consumed in a sufficient extent as a consequence of irregular and unbalanced diet. Therefore increasing interest arises in exploiting naturally derived plant products as sources of bioactive ingredients, in order to increase their intake and positive health effects. Among plant materials, carob (Ceratonia siliqua L.) and cocoa husk (Theobroma cocoa L.) have in common a high content of dietary fibres and polysaccharides, but a lack of information exists regarding their antioxidant capacity and polyphenolic profile. In this study the bioactive composition and antioxidant properties, as well as the content of dietary fibers and sugars in carob and cocoa husk, affected by different extraction techniques (hydrolysis, ultrasonic, conventional) and solvents (aqueous mixtures of acetone and ethanol) was evaluated using spectrophotometric and high performance liquid chromatography (HPLC) methods. Cocoa husk exhibited higher total dietary fibre content, but lower content of fructose and glucose, in comparison to carob, which was also characterized with a significant content of sucrose. Both acid and alkali hydrolysis of raw materials provided the highest content of polyphenolic compounds and antioxidant capacity, which could be attributed to interferences in the measurement procedure and non-selectivity of employed reagents. By comparing non-hydrolysed samples, the highest total phenol content (TPC) was determined in extracts prepared using 80% acetone (carob-15.2 mg gallic acid equivalents/g DM, cocoa husk-4.8 mg GAE/g DM). The ranking of samples according to their total flavonoid content and antioxidant capacity corresponds to their TPC order (80% acetone > 50% ethanol > 70% ethanol). HPLC analysis revealed the prevalence of methylxanthines in cocoa husk and gallic acid and its derivatives in carob. The evaluated plant materials represent rich sources of carbohydrates, as well as polyphenolic antioxidants, while the content of these compounds is dependent on the employed extraction technique and solvent.