Extraction of Anthocyanins and Total Phenolic Compounds from Açai (Euterpe oleracea Mart.) Using an Experimental Design Methodology. Part 3: Microwave-Assisted Extraction

Abstract

In this work, two methods based on microwave-assisted extraction techniques for the extraction of both anthocyanins and total phenolic compounds from açai have been developed. For that, a full factorial design (Box-Behnken design) has been used to optimize the following four variables: solvent composition (25–75% methanol in water), temperature (50–100 °C), pH (2–7), and sample/solvent ratio (0.5 g: 10 mL–0.5 g: 20 mL). The anthocyanins and total phenolic compounds content have been determined by ultra high-pressure liquid chromatography and Folin-Ciocalteu method, respectively. The optimum conditions for the extraction of anthocyanins were 38% MeOH in water, 99.63 °C, pH 3.00, at 0.5 g: 10 mL of ratio, while for the extraction of total phenolic compounds they were 74.16% MeOH in water, 99.14 °C, pH 5.46, at 0.5 g: 20 mL of ratio. Both methods have shown a high repeatability and intermediate precision with a relative standard deviation lower than 5%. Furthermore, an extraction kinetics study was carried out using extraction periods ranging from 2 min until 25 min. The optimized methods have been applied to açai-containing real samples. The results with such real samples have confirmed that both methods are suitable for a rapid and reliable extraction of anthocyanins and total phenolic compounds.

Anthocyanins: A Comprehensive Review of Their Chemical Properties and Health Effects on Cardiovascular and Neurodegenerative Diseases

“…Other good sources of anthocyanins include purple corn, cherries, plums, pomegranate, eggplant, wine, grapes, and red/purple vegetables such as black carrots, red cabbage and purple cauliflower which may contain from a few milligrams up to 200–300 mg/100 g of product [ 72 , 73 ]. More recently, anthocyanins have been identified in numerous berries whose production and consumption is steadily increasing, such as maqui [ 74 , 75 ], myrtle [ 76 , 77 ], and açai [ 78 , 79 , 80 ].…”

Optimization of a Novel Method Based on Ultrasound-Assisted Extraction for the Quantification of Anthocyanins and Total Phenolic Compounds in Blueberry Samples (Vaccinium corymbosum L.)

“…The injection volume was set at 3 µL. The chromatographic conditions used as well as the analysis conditions in the mass spectrometer (Q-ToF-MS) are those described by Aliaño et al [42].…”

“…Finally, the detection limit (0.198 mg L −1 ) and the quantification limit (0.662 mg L −1 ) were calculated as was described by Aliaño et al [42]. The UHPLC chromatogram representing the 14 anthocyanins is shown in Figure 1.…”

“…For this reason, the development of new methodologies that allow the extraction of these compounds from the blueberries in a fast, easy to use and reliable way is of great importance. Several analytical extraction techniques such as maceration [35][36][37], Soxhlet [38,39], pressurized liquid extraction [40,41], microwave-assisted extraction [42][43][44], have been employed to obtain rich anthocyanins and phenolic compound extracts from berries. Among them, ultrasound-assisted extraction (UAE) [45] and pressurized liquid extraction (PLE) [46,47] are the most commonly used for the extraction of both bioactive compounds in blueberries.…”

Extraction and Analysis of Natural Product in Plant

“…Aliaño-González et al optimized the extraction of individual anthocyanins and total phenolic compounds from açai (Euterpe oleracea Mart.) using several non-conventional extraction techniques such as ultrasound-assisted extraction (UAE) [2], microwave-assisted extraction (MAE) [3] and pressurized liquid extraction (PLE) [4]. These three studies also employed response surface designs (Box-Behnken) for the optimization of the different variables, including optimal extraction times and the validation of the methods themselves.…”