Studies On The Chemical Constituents And Quality Control Of Cordate Pinellia Tuber

Cordate Pinellia Tuber is a traditional Chinese medicine and 5 batches of samples were collected. The chemical constituents of Cordate Pinellia Tuber and its processed pruducts with Glycyrrhiza, their quantitative analysis methods, and the HPLC fingerprint of this crude drug were investigated in detail.The chemical constituents of Cordate Pinellia Tuber were studied and 6 compounds were isolated by a combination of silica gel and Sephadex LH-20 column chromatography, preparative thin layer chromatography and high preparative performance liquid chromatography, their structures were identified asβ-sitosterol (Ⅰ), vanillic acid (Ⅱ), neoechinulin A (Ⅲ),ρ-hydroxybenzoic acid (Ⅳ), fumaric acid (Ⅴ) and thymine (Ⅵ); Meanwhile, the chemical constituents of Cordate Pinellia Tuber processed with Glycyrrhiza were studied and 4 compounds were isolated by similar chromatography skills, their structures were identified as 3-oxoglycyrrhetic acid (Ⅶ), licochalcone A (Ⅷ), isoliquiritigenin (Ⅸ) and glycyrrhetinic acid (Ⅹ). CompoundsⅠ-Ⅵare isolated from Cordate Tuber for the first time; CompoundsⅢ,Ⅳ,Ⅵwere firstly isolated from herbs of Pinellia; CompoundsⅦ～Ⅹbelong to chemical continents of Glycyrrhiza.An HPLC quantitative analysis of neoechinulin A in Cordate Pinellia Tuber was performed on a Diamonsil C18 column (250 mm×4.6 mm,5μm) with the mobile phase of methanol-0.1% phosphoric acid solution (63:37,v/v) and detective wavelength of 225 nm. The linear range of neoechinulin A was 2.0～40.0μg·mL-1 (r=0.9995) and the recovery was 98.8%(RSD=1.5%). An HPLC method was established for the simultaneous determination of glycyrrhetinic acid and 3-oxoglycyrrhetic acid in Cordate Pinellia Tuber processed with Glycyrrhiza. The separation was performed on a Diamonsil C18 column (250 mm×4.6 mm,5μm) with the mobile phase of acetonitrile and water contained 0.1% phosphoric acid solution (85:15, v/v) and detected at 254 nm. The linear ranges of glycyrrhetinic acid and 3-oxoglycyrrhetic acid were 0.0194～0.388 mg·mL－1 (r=0.9996) and 0.0143～0.286 mg·mL-1 (r=0.9992), respectively. The recoveries of the two components were 98.6%(RSD =0.9%) and 100.4% (RSD=1.1%), respectively. An HPLC quantitative analysis of licochalcone A in Cordate Pinellia Tuber processed with Glycyrrhiza was performed on a Diamonsil C18 column (250 mm×4.6 mm,5μm) with the mobile phase of methanol-0.1% phosphoric acid solution (78:22, v/v) and detective wavelength of 254 nm. The linear range of licochalcone A was 0.011～0.22 mg·mL-1 (r=0.9997) and the recovery was 100.1%(RSD= 1.5%). A quantitative analysis of total alkaloids in Cordate Pinellia Tuber was developed, which was performed by acid dye colorimetry, with determining wavelength at 416 nm. The linear range was 35～105μg·mL-1 (r=0.9970) and the recovery was 97.9%(RSD=2.3%).The HPLC fingerprint of Cordate Pinellia Tuber was estabilished on Dikma Diamonsil C18 column with a mixture liquid of methanol-acetonitrile-0.1% phosphate acid solution as mobile phase in gradient elution and detective wavelength at 254 nm, as well as the method was validated. The 5 batches of Cordate Pinellia Tuber were analyzed and 20 co-peaks were obtained. All samples were classified with hierarchical clustering analysis. The similarity evaluation was completed with angle cosine, correlation coefficient and euclidean distance as measurement.