Ultrasound-Assisted Extraction and Identification of Natural Antioxidants from the Fruit of Melastoma sanguineum Sims

Abstract

The fruit of Melastoma sanguineum Sims is an edible and sweet wild fruit. In our previous study, the fruit was found to have a strong antioxidant property. In this study, an ultrasound-assisted extraction (UAE) method was developed to extract natural antioxidants from the fruit of Melastoma sanguineum Sims, and a response surface methodology was used to optimize the conditions of UAE to maximize the extraction efficiency. The influence of five independent extraction parameters (ethanol concentration, solvent/material ratio, extracting time, temperature, and ultrasound power) on the extraction efficiency were investigated using a single factor experiment, and then a central composite rotatable design was used to investigate the interaction of three key parameters. The results showed that the optimal extraction conditions were 42.98% ethanol, 28.29 mL/g solvent/material ratio, 34.29 min extracting time, 60 °C temperature, and 600 W ultrasound power. Under these conditions, the Trolox equivalent antioxidant capacity (TEAC) value of the extracts was 1074.61 ± 32.56 μmol Trolox/g dry weight (DW). Compared with conventional maceration (723.27 ± 11.61 μmol Trolox/g DW) and Soxhlet extraction methods (518.37 ± 23.23 μmol Trolox/g DW), the UAE method improved the extraction efficiency, in a shorter period of time. In addition, epicatechin gallate, epicatechin, rutin, epigallocatechin, protocatechuic acid, chlorogenic acid, and quercetin, were identified and quantified in the fruit extracts of Melastoma sanguineum Sims by UPLC-MS/MS.

Characterization of pomegranate peel extracts obtained using different solvents and their effects on cell cycle and apoptosis in leukemia cells

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Microwave-Assisted Extraction of Natural Antioxidants from the Exotic Gordonia axillaris Fruit: Optimization and Identification of Phenolic Compounds

“…The phenolic components in the extract obtained under optimal condition was analyzed according to the method described previously by Zhou et al with slight modifications [ 62 ]. An AB SCIEX 4000 QTRAP LC-MS/MS system (SCIEX, Framingham, MA, USA) was used, equipped with an Acquity UPLC ® HSS T3 column (3.0 × 150 mm, 1.8 µm, Waters, Milford, MA, USA) for the separation of phenolic components at 40 °C.…”

Chemical Fingerprint of Free Polyphenols and Antioxidant Activity in Dietary Fruits and Vegetables Using a Non-Targeted Approach Based on QuEChERS Ultrasound-Assisted Extraction Combined with UHPLC-PDA

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