In this work, a high-speed countercurrent chromatography (HSCCC) method was established for the preparation of phorbol esters (PEs) from Jatropha curcas. n-Hexane–ethyl acetate–methanol–water (1.5:1.5:1.2:0.5, v/v) was selected as the optimum two-phase solvent system to separate and purify jatropha factor C1 (JC1) with a purity of 85.2%, as determined by HPLC, and to obtain a mixture containing four or five PEs. Subsequently, continuous semipreparative HPLC was applied to further purify JC1 (99.8% as determined by HPLC). In addition, UPLC–PDA and UPLC–MS were established and successfully used to evaluate the isolated JC1 and PE-rich crude extract. The purity of JC1 was only 87.8% by UPLC–UV. A peak (a compound highly similar to JC1) was indentified as the isomer of JC1 by comparing the characteristic UV absorption and MS spectra. Meanwhile, this strategy was also applied to analyze the PE-rich crude extract from J. curcas. It is interesting that there may be more than 15 PEs according to the same quasi-molecular ion peaks, highly similar sequence-specific fragment ions, and similar UV absorption spectrum.

As an important edible and medicinal material, tartary buckwheat (Fagopyrum tataricum Gaertn.) is commonly used as a kind of food or drug in eastern Asian countries. To investigate the pharmacokinetic profile of total quercetin after a single oral dose of tartary buckwheat extract in rats, a sensitive, simple, and accurate HPLC−UV method was developed to determine total quercertin following plasma enzyme hydrolysis with glucuronidase/sulfatase. Eighteen male Wistar rats were randomly assigned into three groups, which were given three different doses of tartary buckwheat extract. The pharmacokinetic results showed that the area under the plasma concentration−time curve (AUC) of total quercetin after single oral doses of tartary buckwheat extract presented a linear relationship. The peak plasma concentrations (Cmax) of total quercetin afte plasma enzyme hydrolysis with glucuronidase/sulfatase were 0.55 ± 0.26, 1.10 ± 0.53, and 2.05 ± 0.26 μg/mL; the peak times (Tmax) were 2.33 ± 1.94, 2.75 ± 3.67, and 2.50 ± 1.82 h; the areas under the curves (AUC0−36h) were 5.29 ± 1.35, 10.02 ± 4.43, and 22.51 ± 3.05 μg·mL−1·h−1 for three doses of tartary buckwheat extract (60, 120, and 240 mg/kg). The present study has provided a basic pharmacokinetic profile of total quercetin after a single oral dose of tartary buckwheat extract in rats.