Methods For Analysis Of Procyanidins In Hawthorn And Studies On Their Stability

Hawthorn(Crataegus) contains a large of procyanidin(PC) and is a sort of important latent resource. According to present studies on PC of Hawthorn, the paper established two analytic methods to determine the contents of Hawthorn materials, extract and products. By the two methods, the stability of PC in Hawthorn was evaluated and studied.Photometric assay was developed to determine the contents of PC in samples at 400 run absorption wavelength with ammonium molybdate as catalytic agent and epicatechin as reference standard. According to analysis step, there were excellent linearity correlation between the concentration and peak areas of four components with range from 30 to 70 μg/mL and correlation coefficient (r) was 0.9999. The average recovery ratio was 105.5% at 70-84 μg/mL adding level. The RSD (n=5) was 0.34%. The detection limit was 2.1 μg/mL.A suit of high performance liquid chromatographic(HPLC) method was established for analyzing the main active components of Hawthorn by homemade high performance liquid chromatographic apparatus. Column: Hypersil BDS C₁₈ (4.6 mm id × 250 mm, 5 μm) ; temperature: 20℃; mobile phase: methanol / acetonitrile / water = 21/2/77, including 500 ug/mL formic acid; flow: 0.8 mL/min; detection: UV at 280 nm; injection quantity: 10 μL. By the method, the main active components in Hawthorn, Epicatechin, Procyanidin B₂, Procyanidin C₁, Chlorogenic acid, were separated and determined well in 20 minutes. The external standard calibration curves were used in quantification. RSD of several components were 0.36%¹.52%. The detection limit was 0.144 ng⁰.309 ng. The linearity rang was 0.01-10.0 μg/mL. The correlation coefficient(r) was 0.9998-0.9999. Both methods were simple, rapid and precise. Ammonium molybdate photometric assay suits estimation of the total PC contents in Hawthorn and HPLC enables quantification of single PC in Hawthorn. The both methods complement each other and could be used for quality control and determination of PC in Hawthorn materials, extracts and preparations.The PC contents in Hawthorn fruits, powders and slices were obtained using photometric assay and HPLC, which indicated that the total contents of PC in dry products were 4-5 times as much as that in Hawthorn fruits and several main active...