%0 Journal Article
%T Cloud-Point Extraction Combined with Liquid Chromatography for the Determination of Ergosterol, a Natural Product with Diuretic Activity, in Rat Plasma, Urine, and Faeces
%A Dan-Qian Chen
%A Jun-Min An
%A Ya-Long Feng
%A Ting Tian
%A Xiang-Yang Qin
%A Ying-Yong Zhao
%J Journal of Analytical Methods in Chemistry
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/479056
%X Ergosterol from many medicinal fungi has been demonstrated to possess a variety of pharmacological activities in vivo and in vitro. A new method based on cloud-point extraction has been developed, optimized and validated for the determination of ergosterol in rat plasma, urine and faeces by liquid chromatography. The non-ionic surfactant Triton X-114 was chosen as the extract solvent. The chromatographic separation was performed on an Inertsil ODS-3 analytical column with a mobile phase consisting of methanol and water (98£¿:£¿2, v/v) at a flow rate of 1£¿mL/min. The methodology was validated completely. The results indicated good performance in terms of specificity, linearity, detection and quantification limits, precision and accuracy. The method was successfully applied to the pharmacokinetic studies of ergosterol in rats. The results indicate that the ergosterol levels in feces are much higher than those in plasma and urine of the rat. 1. Introduction Ergosterol is one of the best-known steroids, which exists widely in many medicinal fungi such as Polyporus umbellatus, Cordyceps sinensis, and Hypsizigus marmoreus [1¨C3]. We have recently reported the ergosterol has diuretic activity from Polyporus umbellatus [4]. Ergosterol has also been reported to possess cytotoxic activity [5] and anti-inflammatory activity [3]. Despite the fact that ergosterol showed multiple pharmacological activities, several pharmacokinetic and biochemical aspects of this compound remain unclear. However, the final effect of the drug in vivo might be influenced by many factors, such as body-and/or cell-compartment distribution, drug metabolism, lipophilicity, membrane permeability, and protein binding. So, these multiple pharmacological activities of ergosterol make it worth carrying out further study on pharmacokinetic properties and elimination pathway of ergosterol. A number of methods have been reported for the quantification of ergosterol in raw materials, such as high performance liquid chromatography-ultraviolet detection (HPLC-UV) [1, 6¨C11], high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) [12, 13], and gas chromatography-mass spectrometry (GC-MS) [14¨C16]. To the best of our knowledge, there is no information describing the quantification of ergosterol in biological samples such as rat or human plasma, urine, and faeces. In addition, the effects on the elimination pathway of ergosterol have not been reported. In general, preclinical research including metabolism and pharmacokinetics of herbal medicine components are of great importance in
%U http://www.hindawi.com/journals/jamc/2013/479056/