Preparation of Cyclocarya paliurus leaves extracts and phytochemical analysis
Cyclocarya paliurus leaves extracts (CP)were provided by Chenzhou Ming run biological products Co. LTD Hunan, China. The license number of this product is QS431006011417.The leaves of C. paliurus has long been used as a bitter Traditional Chinese Medicine which has also been historically used as an herbal tea in the folk. Nowadays, the products derived from the leaves of C. paliurus have become a very popular health product in China (The composition of the C. paliurus leaves extracts was determined by high performance liquid chromatography (HPLC, Agilent 1200, USA) equipped with Agilent 5 TC-C18 (4.6 mm ×250 mm, 5μm). The system parameters were set as follows: injection volume, 5μL; the column temperature, 30°C; and the mobile phase flow rate, 0.8mL/min. The mobile phase consisted of two solvents: (A) 0.2% aqueous acetic acid and (B) acetonitrile. The elution conditions were as follows: 0–5min, gradient 5% B; 5–10 min, linear gradient 5–10% B; 10–15 min, linear gradient 10–25% B; 15–25 min, linear gradient 25–40% B; 25–30min, linear gradient 40–90% B. Peaks were detected at 254 nm. The quantification of different component monomers was based on the peak areas and calculated as equivalents of the standard compounds; all contents were expressed as mg/g component dry weight. The temperature of the column oven was set at 40 °C, the flow rate was set at 0.6 mL/ min and the injection volume was 5 µL.