RESUMEN
Objective:To develop a method for the determination of natural benzoic acid in Mesona chinensis Benth. with different production places and storage time. Methods:HPLC was adopted, the column was an Agilent ZORBAX SB-C18 (250 mm × 4. 6 mm, 5 μm) column, the mobile phase was methanol-0. 02 mol·L-1 ammonium acetate (5∶95) at the flow rate of 1. 0 ml·min-1 , the col-umn temperature was 35℃, the detection wavelength was 230 nm, and the injection vocume was 10μl. Results:Benzoic acid showed good linearity over the concentration range of 0. 1-10. 0 μg·ml-1(r=0. 999 9). The average recovery was 99. 59%(RSD=1. 57%, n=9). Natural benzoic acid in powered Mesona chinensis Benth. was different because of various production places. The maximum content of natural benzoic acid in Mesona chinensis Benth. was 141. 8 mg·kg-1, while the minimum content was 73. 8 mg·kg-1. The content of natural benzoic acid in Mesona chinensis Benth. stored for two years was declined obviously. Conclusion: The method with simple operation is accurate and reproducible. It can provide a basis for the further study of Mesona chinensis Benth. resources, and provide a reference for the content determination of natural benzoic acid in other plants.