Quantitative HPLC Analysis and Extraction of 2,6-dimethoxy-1,4-benzoquinone from Ficus foveolata Stems

An antibacterial benzoquinone, 2,6-dimethoxy-1,4-benzoquinone, isolated from Ficus foveolata stems was used as a standard marker for establishment of quantitative HPLC analysis for the stem extracts of F. foveolata. The method utilized a TSK-gel ODS-80Ts column (5 μm, 4.6 × 250 mm) with the mixture of methanol and 5% acetic acid in water (24:76, v/v) as the mobile phase at a flow rate of 1 mL/min, and quantitative detection at 289 nm. The parameters i.e. linearity, intraday and interday precision, accuracy, specificity and sensitivity of the method were evaluated for method validation. The recoveries of the method were 99.5 - 103.6% and good linearity (R² ≥ 0.9999) was obtained. A high degree of specificity, sensitivity as well as repeatability and reproducibility (RSD less than 2 and 5%, respectively) were also achieved. Chloroform was served as the most suitable solvent for extraction of 2,6-dimethoxy-1,4-benzoquinone. The optimised sample preparation and HPLC method can be practically used in the routine quality control process of F. foveolata stem extracts.