Development of a microwave-assisted extraction for the analysis of phenolic compounds from Rosmarinus officinalis

For potent biological activity natural phenols are considered as compounds with perspective of being isolated in their pure form from natural sources. For analytical purposes, as well as for potential industrial application, it is important to apply extraction procedure that allows efficient and time-consuming extraction of polyphenols. In this study a microwave-assisted extraction procedure has been optimized in respect to the recovery of rosemary polyphenols. The optimization was performed in respect to total polyphenols, flavonoids, total anthocyanins, monomeric and condensed anthocyanins. The efficiency of different solvents was investigated for different classes of polyphenols, as well as the influence of the magnetron power and the extraction time. The efficiency of the extraction using optimized extraction protocol for total phenolics was compared with that achieved by Soxhlet and ultrasound-assisted extraction. The present work proposes an optimal microwave-assisted extraction program for the determination of total polyphenolics, flavonoids, total anthocyanins, monomeric and condensed anthocyanins from rosemary.