RESUMEN

This study aimed to identify ellagitannins in black raspberry seeds (BRS) and to optimize accelerated solvent extraction of ellagitannins using an artificial neural network (ANN) coupled with genetic algorithm. Fifteen monomeric and dimeric ellagitannins were identified in BRS. For ANN modeling, extraction time, extraction temperature, and solvent concentration were set as input variables, and total ellagitannin content was set as output variable. The trained ANN had a mean squared error value of 0.0102 and a regression correlation coefficient of 0.9988. The predicted optimal extraction conditions for maximum total ellagitannin content were 63.7% acetone, 4.21 min, and 43.9 °C. The actual total ellagitannin content under the optimal extraction conditions was 13.4 ± 0.0 mg/g dry weight, and the prediction error was 0.75 ± 0.27%. This study is the first attempt to analyze the composition of ellagitannins in BRS and to determine optimal extraction conditions for maximum total ellagitannin content from BRS.

Asunto(s)

Nigella sativa , Rubus , Taninos Hidrolizables , Redes Neurales de la Computación , Semillas , Solventes

RESUMEN

This study aimed to determine bioactive components and radical scavenging capacity of black raspberry seed extracts as byproducts obtaining during the juice (FSE) and wine (WSE) making process. Cyanidin-3-O-rutinoside was identified as a major anthocyanin and the total anthocyanin contents of fresh and wine seed were 78.24 and 41.61 mg/100 g of dry weight, respectively. The total phenolic and flavonoid contents of FSE and WSE were 2.31 g gallic acid equivalent (GAE) and 360.95 mg catechin equivalent (CE), and 2.44 g GAE and 379.54 mg CE per 100 g dry weight, respectively. The oxygen radical absorbance capacity (ORAC) values were 1041.9 µM TE/g for FSE and 1060.4 µM TE/g for WSE. Pretreatment of the FSE and WSE inhibited the generation of intracellular reactive oxygen species (ROS), DNA and protein damage induced by hydroxyl radicals, and Fe(3+)/ascorbic acid-induced lipid peroxidation in a dose dependent manner. WSE more effectively protected from oxidative damage than FSE. Results from the current study suggest that black raspberry seeds as byproducts from juice and wine processing could be potential sources for natural antioxidants.