MICROWAVE-ASSISTED OBTAINING OPTIMIZATION OF HYDROALCOHOLIC EXTRACT FROM JUSTICIA PECTORALIS JACQ

Abstract

Justicia pectoralis Jacq., widely used in traditional Cuban medicine as sedative and anxiolytic. Its main components, coumarins, have a recognized sedative activity, are used as markers in various extracts obtained from this plant. The hydroalcoholic extract 30% is used as raw material in the preparation of syrup. Microwave assisted extraction is of recognized importance because of the speed and efficiency in obtaining phytoconstituents compared to conventional methods and Response Surface Methodology is an efficient statistical tool that has been successfully used in testing process parameters and their interactive effects. The objtetive of this work was optimize the obtaining of the hydroalcoholic extract 30% of Justicia pectoralis Jacq. by means of microwave energy through a Box-Behnken design under the response surface methodology. A Sanyo EM-T109SS modified domestic microwave oven was used. Three variables irradiation power (540 – 900 W), time (2-5 min), and liquid to solid ratio (10 -20 mL/g) were regarded as factors in the response surface design of Box-Behnken of 15 executions, including 3 center points. The yield of total coumarins was used as the response variable. The optimal conditions were 4 min at 540 W and a liquid to solid ratio of 20 ml/g for a predicted value of total coumarins of 0.48 mg/g. Compared to the traditional method by reflux (2 h and 0.42 mg/g), the EAM demonstrated significant time savings, with greater recovery of coumarins. The results showed that microwave-assisted extraction can be used as an efficient method to obtain hydroalcoholic extract of Justicia pectoralis Jacq.