Red Fruits: Extraction of Antioxidants, Phenolic Content, and Radical Scavenging Determination: A Review

Abstract

Red fruits, as rich antioxidant foods, have gained over recent years capital importance for consumers and manufacturers. The industrial extraction of the phenolic molecules from this source has been taking place with the conventional solvent extraction method. New non-conventional extraction methods have been devised as environmentally friendly alternatives to the former method, such as ultrasound, microwave, and pressure assisted extractions. The aim of this review is to compile the results of recent studies using different extraction methodologies, identify the red fruits with higher antioxidant activity, and give a global overview of the research trends regarding this topic. As the amount of data available is overwhelming, only results referring to berries are included, leaving aside other plant parts such as roots, stems, or even buds and flowers. Several researchers have drawn attention to the efficacy of non-conventional extraction methods, accomplishing similar or even better results using these new techniques. Some pilot-scale trials have been performed, corroborating the applicability of green alternative methods to the industrial scale. Blueberries (Vaccinium corymbosum L.) and bilberries (Vaccinium myrtillus L.) emerge as the berries with the highest antioxidant content and capacity. However, several new up and coming berries are gaining attention due to global availability and elevated anthocyanin content.

Fruits of wild and semi‐domesticated Diospyros tree species have contrasting phenological, metabolic, and antioxidant activity profiles

“…However, the lower relative humidity recorded at this site in the 2015 winter 20 could have stimulated TPC and TF accumulation, similar to the increased phenolic content detected in chokeberries juice in response to reduced relative humidity. 48 It remains to be determined whether other factors not measured at the sampling site, 20 such as day/night growing temperature combinations, tree water intake, and degree of ripening at fruit harvest, also known to affect the accumulation of these compounds in red fruits, 49,50 were determining factors influencing the yearly fluctuation in TPC and TF content observed in D. rekoi fruits. The major soluble phenols found in Diospyros fruits include phenolic acids, catechins, and hydrolyzed tannins, whereas rutin is an abundant flavonoid.…”

Enzyme‐Assisted Extraction of Bioactive Compounds from Raspberry (Rubus idaeus L.) Pomace

“…The recovery of bioactive compounds from red fruits and their by-products has been recently reported by Hidalgo and Almajano (2017). In this study, eco-friendly extraction processes were proposed as alternatives to conventional maceration and organic solvent extraction methods.…”

Solvent and Rotating Bed Reactor Extraction with One- and Two-Phase Solvents Applied to Bilberries (Vaccinium myrtillus) for Isolating Valuable Antioxidants

“…Bilberries have been demonstrated as important resources for anthocyanidin (550-850 mg/100 g) (Heffels et al 2015;Hidalgo and Almajano 2017;Maatta-Riihinen et al 2004).…”

“…These are compared to each other and to classical extraction. Others have also used microwave extraction or supercritical CO 2 which we did not have available (Babova et al 2016;Eliasson et al 2017;Fidale et al 2016;Hidalgo and Almajano 2017).…”