[Show abstract][Hide abstract] ABSTRACT: Simultaneous determination of polydatin and its metabolite in excrement samples using high-performance liquid chromatography (HPLC) with UV detection was accomplished. After extracted them by C18 solid phase extraction, the samples were separated on a reversed-phase column. Detection wave-lengths were set at 306 nm. The separation was carried out with a gradient elution. The mobile phase was acetonitrile-water (containing 0.1% formic acid) at a flow rate of 1.0 ml.min(-1). The identities of the peaks were accomplished by comparing retention times, UV and mass data with reference compounds under the same conditions. The standard curve was rectilinear in the range of 0.803-642.6 microg x ml(-1) (r=1.0000) for polydatin, 0.407-325.8 microg x ml(-1) (r=1.0000) for resveratrol. The recoveries of the markers listed above were 102.2% and 97.3%, respectively. The verified method can be used to determine the contents of two compounds in samples of stomach, small intestine, caecum, and large intestine (including excrement) of rats fed with polydatin. The analytical results demonstrated that the metabolism of polydatin is mainly processed in the intestines; polydatin can be transformed into resveratrol by de-sugaring process.
[Show abstract][Hide abstract] ABSTRACT: An RP-HPLC method was developed for the first time to simultaneously determine five major compounds in Polygonum cuspidatum, namely resveratrol, polydatin, anthraglycoside B, emodin and physcion with UV detection at 306nm. The column was an Agilent
Zorbax SB-C18 (250×4.6mm i.d., 5μm). The separation was carried out with a gradient program. The mobile phase was acetonitrile–water
(containing 0.1% formic acid) at a flow rate of 1.0mLmin−1. The standard curve was rectilinear in the range of 2.04–62.96μgmL−1 (r=0.9998) for resveratrol, 20.13–239.7μgmL−1 (r=0.9998) for polydatin, 7.19–71.92μgmL−1 (r=1.0000) for anthraglycoside B, 2.68–83.68μgmL−1 (r=0.9998) for emodin and 0.60–14.37μgmL−1 (r=0.9997) for physcion. The recoveries of the markers were 96.0, 106.5, 97.8, 97.9 and 98.1%, respectively. The relative standard
deviation of intra-day and inter-day were less than 5.0 and 2.3%. This method was simple, accurate and reproducible. The developed
method was successfully applied to analyze five compounds in P. cuspidatum of 20 commercial brands.