Optimization of Microwave-Assisted Extraction for the Recovery of Bioactive Compounds from the Chilean Superfruit (Aristotelia chilensis (Mol.) Stuntz)

Abstract

Maqui berry (Aristotelia chilensis) is being explored in the food industry, and is considered to be one of the healthiest berries due to its bioactive components and high commercial value. Microwave-assisted extraction (MAE) was developed for the determination of total phenolic compounds and anthocyanins from maqui. A Box–Behnken experimental design was employed in conjunction with a response surface methodology to optimize the conditions based on 27 different experiments. The extractions were carried out with four factors (i.e., methanol percentage, pH, temperature, and solvent volume:sample mass ratio), and two responses—total phenolics and anthocyanins. Temperature and methanol percentage were found to be the most influential parameters for total phenolic compounds and anthocyanins, respectively. The optimum MAE conditions were: 65% MeOH in water at pH 2, temperature of 100 °C, and a ratio of 10:0.5 for total phenolics; and 60% MeOH in water at pH 2, temperature of 50 °C, and a ratio of 14:0.5 for anthocyanins. Kinetics assays were carried out and an optimum time of only 2 min was identified for the extractions. Repeatability and intermediate precision were also evaluated, and coefficients of variation below 5% were obtained. The new methods were successfully applied to a foodstuff made with maqui.

Ultrasound-Assisted Extraction of Two Types of Antioxidant Compounds (TPC and TA) from Black Chokeberry (Aronia melanocarpa L.): Optimization of the Individual and Simultaneous Extraction Methods

“…There are numerous studies that analyze only specific optimal extraction conditions for particular compounds in other matrices [39,40]. However, certain factors such as time and costs are very important for quality control and analytical laboratories, it is, therefore, necessary to determine optimum balanced conditions that allow us to satisfactorily extract TPC and TA at the same time.…”

“…As explained above for anthocyanins, before the identification and quantification of sugars, the influence of several factors that can affect their extraction was evaluated: temperature (10,20,30,40,50, 60, 70 • C), percentage of methanol (0, 10, 20, 40, 60%) and time (2, 5, 10, 15, 20, 25, 30 min). For each experiment 0.5 g of sample were weighed, UAE was performed, and then the extracts were filtered and placed in a 25 mL volumetric flask.…”

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 ].…”

Assessment of Ultrasound Assisted Extraction as an Alternative Method for the Extraction of Anthocyanins and Total Phenolic Compounds from Maqui Berries (Aristotelia chilensis (Mol.) Stuntz)

“…The results obtained by means of UAE were compared to those achieved by MAE methods. The samples were analyzed according to the optimal conditions determined in a previous work [61]. Approximately half of the commercial samples analyzed show statistically significant differences with regards to total phenolic compounds content.…”