title: Application of Ultrasound in a Closed System: Optimum Condition for Antioxidants Extraction of Blackberry (Rubus fructicosus) Residues.
abstract: Blackberry processing generates up to 20% of residues composed mainly of peel, seeds and pulp that are abundant in flavonoids. The objective of this study was to optimize the ultrasound conditions, in a closed system, for antioxidants extraction, using the response surface methodology. Blackberry (Rubus fructicosus) residues were analyzed for total phenolics, total anthocyanins, and antioxidant activity by ABTS and DPPH. The selected independent variables were ultrasound amplitude (X₁: 80%-90%) and extraction time (X₂: 10-15 min), and results were compared with conventional extraction methods. The optimal conditions for antioxidants extraction were 91% amplitude for 15 min. The results for total phenolic content and anthocyanins and antioxidant activity by ABTS and DPPH were of 1201.23 mg gallic acid equivalent (GAE)/100 g dry weight basis (dw); 379.12 mg/100 g·dw; 6318.98 µmol Trolox equivalent (TE)/100 g·dw and 9617.22 µmol TE/100 g·dw, respectively. Compared to solvent extraction methods (water and ethanol), ultrasound achieved higher extraction of all compounds except for anthocyanins. The results obtained demonstrated that ultrasound is an alternative to improve extraction yield of antioxidants from fruit residues such as blackberry.
authors.affiliation: Instituto de Ciencias Agropecuarias, Universidad Aut&#243;noma del Estado de Hidalgo, Av. Universidad Km 1, Rancho Universitario, Tulancingo de Bravo, Hidalgo 43600, Mexico. zafhry@hotmail.com.
authors.forename: Quinatzin Y
authors.initials: QY
authors.lastname: Zafra-Rojas
authors.affiliation: Centro de Investigaci&#243;n Interdisciplinario, &#193;rea Acad&#233;mica de Nutrici&#243;n, Instituto de Ciencias de la Salud, Universidad Aut&#243;noma del Estado de Hidalgo, Circuito Actopan-Tilcuautla s/n. Ex hacienda La Concepci&#243;n, San Agust&#237;n Tlaxiaca, Hidalgo 42160, Mexico. ncruz@uaeh.edu.mx.
authors.forename: Nelly S
authors.initials: NS
authors.lastname: Cruz-Cansino
authors.affiliation: Instituto de Ciencias Agropecuarias, Universidad Aut&#243;noma del Estado de Hidalgo, Av. Universidad Km 1, Rancho Universitario, Tulancingo de Bravo, Hidalgo 43600, Mexico. auroraql@yahoo.com.mx.
authors.forename: Aurora
authors.initials: A
authors.lastname: Quintero-Lira
authors.affiliation: Centro de Investigaciones Qu&#237;micas, Instituto de Ciencias B&#225;sicas e Ingenier&#237;a, Universidad Aut&#243;noma del Estado de Hidalgo, Centro Universitario, Carretera Pachuca-Tulancingo Km 4.5, Mineral de la Reforma, Hidalgo 42183, Mexico. cgomeza@uaeh.edu.mx.
authors.forename: Carlos A
authors.initials: CA
authors.lastname: Gómez-Aldapa
authors.affiliation: Centro de Investigaci&#243;n Interdisciplinario, &#193;rea Acad&#233;mica de Nutrici&#243;n, Instituto de Ciencias de la Salud, Universidad Aut&#243;noma del Estado de Hidalgo, Circuito Actopan-Tilcuautla s/n. Ex hacienda La Concepci&#243;n, San Agust&#237;n Tlaxiaca, Hidalgo 42160, Mexico. ealanisg70@yahoo.com.mx.
authors.forename: Ernesto
authors.initials: E
authors.lastname: Alanís-García
authors.affiliation: Instituto de Ciencias Agropecuarias, Universidad Aut&#243;noma del Estado de Hidalgo, Av. Universidad Km 1, Rancho Universitario, Tulancingo de Bravo, Hidalgo 43600, Mexico. elizarraras.alice@yahoo.com.mx.
authors.forename: Alicia
authors.initials: A
authors.lastname: Cervantes-Elizarrarás
authors.affiliation: Instituto de Ciencias Agropecuarias, Universidad Aut&#243;noma del Estado de Hidalgo, Av. Universidad Km 1, Rancho Universitario, Tulancingo de Bravo, Hidalgo 43600, Mexico. njgv2002@yahoo.com.mx.
authors.forename: Norma
authors.initials: N
authors.lastname: Güemes-Vera
authors.affiliation: Centro de Investigaci&#243;n Interdisciplinario, &#193;rea Acad&#233;mica de Nutrici&#243;n, Instituto de Ciencias de la Salud, Universidad Aut&#243;noma del Estado de Hidalgo, Circuito Actopan-Tilcuautla s/n. Ex hacienda La Concepci&#243;n, San Agust&#237;n Tlaxiaca, Hidalgo 42160, Mexico. esther_ramirez@uaeh.edu.mx.
authors.forename: Esther
authors.initials: E
authors.lastname: Ramírez-Moreno
mesh_terms: D000872:Anthocyanins / Q000737:chemistry; D000975:Antioxidants / Q000737:chemistry* / Q000302:isolation & purification* / Q000494:pharmacology; D005591:Chemical Fractionation / Q000379:methods; D010636:Phenols / Q000737:chemistry; D010936:Plant Extracts / Q000737:chemistry* / Q000302:isolation & purification* / Q000494:pharmacology; D015203:Reproducibility of Results; D065856:Rubus / Q000737:chemistry*; D000069453:Ultrasonic Waves
chemical_list: D000872:Anthocyanins; D000975:Antioxidants; D010636:Phenols; D010936:Plant Extracts
keywords: antioxidants; blackberry; extraction; residues; ultrasound