The aim of this work was to study an approach for the preparation of high-purity xanthoxylin from Zanthoxylum bungeanum Maxim. Xanthoxylin was extracted by simultaneous distillation extraction (SDE), crude xanthoxylin was isolated using a silica gel column, and high-purity xanthoxylin was obtained by recrystallization. Nuclear magnetic resonance (NMR) and reversed phase high performance liquid chromatography (RP-HPLC) were used for qualitative and quantitative analysis, respectively. During the SDE, the following conditions were used: material to water ratio 1: 10; solvent volume 60 mL; extraction time 1.5 h. RP-HPLC analysis showed that the xanthoxylin content in the crude extract was 47.26%. Crude xanthoxylin was isolated using a silica gel column under the following conditions: eluent ratio (ethyl acetate: petroleum ether) 1: 15; diameter to height ratio 1:12; sample to silica gel ratio 1:40; eluent rate 4 mL/min. The purity of the isolated xanthoxylin was 81.79% and the recovery was 99.12%. Finally, high-purity xanthoxylin (98.23%) was obtained by recrystallization; the total recovery was 90.63% and the yield was 0.88%. NMR analysis showed that the isolated crystal was xanthoxylin. Thus, this approach could achieve the preparation of high-purity xanthoxylin, with high-recovery, from the leaves of Zanthoxylum bungeanum and serve as a reference for broadening the scope of Zanthoxylum bungeanum deep-processing.
