Study on chemical constituents and determination of cannabidiol (CBD) in hemp leaves of Heilongjiang province

Abstract:

The purpose of this research is to study the chemical constituents in the leaves of Heilongjiang han hemp and establish a method for the determination of cannabidiol (CBD). The ethyl acetate extract of hemp leaf was separated and purified by silica gel column chromatography, C18 reverse phase medium voltage column and semi preparative chromatography to obtain 5 monomer compounds. And the structure of these compounds was determined by nuclear magnetic (NMR) analysis. They were cannabidiol (CBD), cannabigerol (CBG), cannabinol (CBN), Δ9-Tetrahydrocannabinolic acid (Δ9-THCA) and cannabichromene (CBC). By using petroleum ether dichloromethane (1∶1) as the developing solvent, iodine and 1% Vanillin ethanol sulfuric acid (10∶1)were used to establish the TLC method for CBD respectively. High performance liquid chromatography (HPLC) detection method for CBD was also established by using acetonitrile 0.05% phosphoric acid solution (80∶20) as mobile phase and selecting the detection wavelength with high CBD absorption peak, which has a good linear relationship at 3.125~100μg/ mL (R2=0.9997), the average recovery rate is 103.69% and RSD is 1.32% (n=5).