Eco-friendly extraction and simultaneous determination of two coumarins in Justicia pectoralis (Acanthaceae)

Abstract

Justicia pectoralis (Acanthaceae) is employed in folk medicine for its analgesic, anti-inflammatory and sedative effects and to treat respiratory diseases. It is known for properties of its coumarins, 1,2-benzopyrone and umbelliferone. A green, simple, fast, and inexpensive ultrasound-assisted extractive (UAE) method for extracting umbelliferone and 1,2-benzopyrone from Justicia pectoralis was optimized. Additionally, a HPLC analytical method was developed and validated for the simultaneous determination of both coumarins. The Box-Behnken design and response surface methodology were used to evaluate the UAE process. Ethanol concentration, extraction time, plant-to-solvent ratio were the independent variables studied and the coumarin content was the dependent one. The HPLC-UV/VIS method was validated in terms of recovery, linearity, accuracy, precision and robustness, proving to be valuable for the quality control of Justicia pectoralis extract and in the development of its herbal products. Results show that the optimal UAE conditions were: ethanol concentration of 15% (w/w), extraction time of 34 min and plant-to-solvent ratio of 0.1 g/mL. The predicted values of coumarin contents (22.16 µg/mL - umbelliferone and 163.86 µg/mL - benzopyrone) were determined under the optimal UAE conditions and proved that UAE is an efficient and eco-friendly extractive process for the production of aerial part extracts from Justicia pectoralis.