The Chemical Composition Of Traditional Chinese Medicine (tcm) Caulis Spatholobi And Quality Control Method

Caulis Spatholobi is the dry vine of Spatholobus Suberectus Dunn.. It has been recorded in the edition 2005 of Pharmacopoeia of the PRC for treating anemia and irregular menstruation. In modern research, the studies on Spatholobus Suberectus Dunn. are mostly about its chemical compositions other than its quality assessment. Along more and more extensive application of Caulis Spatholobi, it is absolutely necessary and urgent to develop a novel quality standard to validly control its quality.The dry vine of Spatholobus Suberectus Dunn. (8 Kg) were extracted with 70% alcohol water solution into an alcoholic extract, which was extracted with ethyl acetate. The ethyl acetate fraction was chromatographed by silica gel, Sephadex LH-20 and polyacylamine chromatography, obtained eight compounds. They were elucidated on the basis of physi-chemical and spectral methods and identified as catechin, epicatechin, gallocatechin, epigallocatechin, formononetin, genistin,β-sitosterol and daucosterol. Among them, epigallocatechin and genistin are isolated from the plant for the first time.We established a method for the determination of catechin and epicatechin in the dry vine of Spatholobus Suberectus Dunn. by reversed phase high performance liquid chromatography (RP-HPLC). Chromatographic separations were achieved on Kromasil C18 (4.6mm×250 mm,5μm) with a gradient of acetonitrile and water as mobile phase at a flow rate of 0.8 mL·min-1 and UV detection at 280nm. The method was linear over the studied range of 15.00-480.0μg·mL-1 (r =0.9998) and 22.80-729.6μg·mL-1 (r=0.9995) for catechin and epicatechin, respectively. The mean recoveries were 97.5% and 97.9% for catechin and epicatechin, respectively. Using the optimized method, the contents of catechin and epicatechin in 8 batches of Spatholobus Suberectus Dunn. were analyzed.The protocatechuic acid in Spatholobus Suberectus Dunn.was determined by reversed phase high performance liquid chromatography (RP-HPLC) for the first time. The determination was performed on Kromasil C18 (4.6mm×250 mm,5μm) using methanol-0.5% aqueous acetic acid (7:93, v/v) as the mobile phase at a flow rate of 1.0 mL·min-1 with a UV detection setting at 260nm. The method was linear over the studied range of 0.44-14.08μg·mL-1 (r=0.9997). The mean recovery was 97.9%. Using the optimized method, the contents of protocatechuic acid in 8 batches of Spatholobus Suberectus Dunn. were analyzed.A simple RP-HPLC method was developed for determination of formononetin in Spatholobus Suberectus Dunn. for the first time. The determination was performed on Kromasil C18 (4.6mm×250 mm,5μm) using acetonitrile-water (35:65, v/v) as the mobile phase at a flow rate of 1.0 mL·min-1 with a UV detection setting at 254nm. The calibration curves of formononetin was linear over the studied range of 0.48-15.36μg·mL-1(r=0.9998). The mean recovery was 98.6%. Using the optimized method, the contents of formononetin in 8 batches of Spatholobus Suberectus Dunn. were analyzed.A simple RP-HPLC method has been established for the quanification of genistin in Spatholobus Suberectus Dunn. for first time. Chromatographic separations were achieved on Kromasil C18 (4.6mm×250 mm,5μm) with acetonitrile-water (15:85, v/v) as mobile phase at a flow rate of 1.0 mL·min-1 and UV detection at 260nm. The method was linear over the studied range of 0.40-12.80μg·mL-1(r=0.9999). The mean recovery was 96.8%. Using the optimized method, the contents of genistin in 8 batches of Spatholobus Suberectus Dunn. were analyzed.The results indicated that the developed HPLC assaies could be readily utilized as quality control methods for Spatholobus Suberectus Dunn..