Assisted extraction of rosemary antioxidants with green solvents

Abstract

The use of natural antioxidants in the food industry has increased in the last years and there is a growing interest in improving the extraction processes using GRAS (general recognize as safe) solvents. In this work the extraction of antioxidants from rosemary with ethanol and water as solvents has been studied using different extraction processes (conventional, microwave assisted – MAE – and ultrasound assisted – USAE –) and plant pretreatments (deoiled and milled, deoiled and fresh plant). Total phenolic compounds in the extracts were determined by the Folin–Ciocalteu assay and HPLC with UV detection was employed for the quantitation of the main antioxidant compounds: rosmarinic acid and carnosic acid. The antioxidant activity of the extract was determined by the DPPHradical dot scavenging assay. The double pretreatment, deoiling by solvent free microwave extraction (SFME) and milling, has shown to be essential to overcome inner mass transfer limitations. Extraction efficiency can be additionally enhanced by microwave and ultrasound assisted extraction process, being this latter more significant in aqueous extracts.Fil: Rodríguez Rojo, Soraya. Universidad de Valladolid. Escuela de Ingenierías Industriales; EspañaFil: Visentin, Alexis Nahuel. Universidad de Valladolid. Escuela de Ingenierías Industriales; España. Universidad Nacional de Rio Cuarto; ArgentinaFil: Maestri, Damian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Cocero, María J.. Universidad de Valladolid. Escuela de Ingenierías Industriales; Españ

Extraction of rosmarinic acid from Melissa officinalis L. by heat-, microwave- and ultrasound-assisted extraction techniques: A comparative study through response surface analysis

“…Due to the RA chemical structure, the use of different water-based solvent mixtures are generally used as the extraction solvent, where the combination of water with different contents of methanol, ethanol or acetone are applied [10,35,36]. Considering the principles of green chemistry, binary mixtures of ethanol with water were selected as the extraction solvent.…”

Solvent extraction effects on phytochemical constituents profiles, antioxidant and antimicrobial activities and functional group analysis of Ecballium elaterium seeds and peels fruits

“…Results of the current investigation show that acetone and diethyl ether extracts exhibited lower levels of antioxidant activity. Acetone is capable to provide high antioxidant activity due to its hydrogen-bonding ability, which is crucial for the extraction of antioxidant phenolic compounds (Rodríguez-Rojo et al, 2012). The efficiency of methanol was related to its intermediate polarity, which allows it to solvate low molecular weight organics compounds possessing protonatable functional groups such as CDDH and DH (Augusto et al, 2014;Nguyen et al, 2015).…”

Ultrasound versus microwave as green processes for extraction of rosmarinic, carnosic and ursolic acids from rosemary

“…Throughout literature, at a laboratory scale, extraction of RA and CA from rosemary leaves has been investigated using different technologies: conventional solvent extraction [10], microwave [11][12][13], ultrasound assisted extraction [12,[14][15][16], supercritical and subcritical fluid extraction [16][17][18] pressurized liquid extraction [18,19], deodorization by Instant Controlled Pressure drop [20] or extraction with ionic liquids [21]. Table 1 details the experimental conditions of the mentioned processes.…”