Chrysophanol

All the six herbal medicines (HMR: RM130121-08; DH: 130524; BS: RM130128-11; KXR: RM121026-04; HP: RM121026-05; ZS: RM121210-11) contained in MZRW were supported and authenticated by PuraPharm Company, Nanning department (Nanning, China). The reference standards of gallic acid, amygdalin, paeoniflorin, hesperidin, neohesperidin, naringin, magnolol, honokiol, aloe emodin, physcion, chrysophanol were purchased from Shanghai Yuan-Ye Bio-technology company (Shanghai, China). Emodin, rhein, albiflorin were purchased from the National Institute for the Control of Pharmaceutical and Biological Products (Beijing, China). The purity of all these reference standards was ≥98.0% (HPLC). HPLC grade of acetonitrile, methanol and formic acid were purchased from Merck (Darmstadt, Germany). Deionized water was purified by the Millipore water purification system (Millipore, Milford, MA, United States). All other reagents used were of analytical grade. Twelve male Sprague-Dawley rats (220–250 g) were kindly provided by the Experimental Animal Center of Chinese University of Hong Kong (Hong Kong). The rats were bred in an environmentally controlled room (22 ± 2°C, relative humidity 50 ± 20%) with a natural light-dark cycle for 7 days before the experiment carried out. The animal study was carried out in accordance with the Guideline for Animal Experimentation of Hong Kong.