Modeling and Optimization of Phenolic Compounds from Sage (Salvia fruticosa L.) Post-Distillation Residues: Ultrasound- versus Microwave-Assisted Extraction

Maria Irakli; Elisavet Bouloumpasi; Stamatia Christaki; Adriana Skendi; Paschalina Chatzopoulou

doi:10.3390/antiox12030549

Modeling and Optimization of Phenolic Compounds from Sage (Salvia fruticosa L.) Post-Distillation Residues: Ultrasound- versus Microwave-Assisted Extraction

Antioxidants (Basel). 2023 Feb 21;12(3):549. doi: 10.3390/antiox12030549.

Authors

Maria Irakli¹, Elisavet Bouloumpasi¹, Stamatia Christaki^{1

2}, Adriana Skendi^{1

3}, Paschalina Chatzopoulou¹

Affiliations

¹ Hellenic Agricultural Organization-DIMITRA, Institute of Plant Breeding and Genetic Resources, Thermi, 57001 Thessaloniki, Greece.
² Department of Food Science and Technology, School of Agriculture, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece.
³ Department of Food Science and Technology, International Hellenic University, 57400 Thessaloniki, Greece.

Abstract

The essential oil production of Salvia fruticosa L. generates considerable amounts of post-distillation solid residues (PRES) which are rich in phenolic compounds. In the present work, the recovery of phenolic antioxidants from PRES by using Microwave-Assisted Extraction (MAE) and Ultrasound-Assisted Extraction (UAE) were separately optimized, according to the Box-Behnken experimental design. The optimization was based on extraction yield, total phenolic content (TPC), total flavonoid content (TFC), rosmarinic acid (RMA), carnosol (CARO), carnosic acid (CARA), and antioxidant activity. The optimal processing parameters were 72% and 68% ethanol, a 15- and 10-min extraction time, a 40 °C and 47 °C extraction temperature, and a 1:30 and 1:10 solid-to-solvent ratio, for MAE and UAE, respectively. Results showed that the levels of RMA, CARO, and CARA in UAE extracts were influenced mainly by ethanol concentration, extraction time, and extraction temperature, while MAE extracts were only influenced by the first two factors. Experimenting with the optimal conditions revealed MAE as more effective than UAE in the recovery of RMA and CARA. The experimental values were in good agreement with the predicted ones, indicating model efficacy in MAE and UAE optimization to effectively extract phenolic compounds from PRES for their further application in food and pharmaceutical industries.

Keywords: Salvia fruticosa; antioxidant activity; carnosic acid; carnosol; microwave-assisted extraction; optimization; phenolic antioxidants; post-distillation; rosmarinic acid; ultrasound-assisted extraction.

Grants and funding

This research has been co-financed by the European Regional Development Fund of the European Union and Greek national funds through the Operational Program Competitiveness, Entrepreneurship and Innovation, under the call RESEARCH—CREATE—INNOVATE (project code: T2EDK-00946).