| At present, the major quality control index of the Extract of bamboo leaves (EBL) is the total flavone glycoside content (TF) determined by A1(NO3)3~ NaNOs spectrophotometry taking rutin as a standard. In order to set up a high-standard quality assurance system, which can be accepted by international society, the quantitative analysis method of TF using by High Performance Liquid Chromatography (HPLC) should be inducted as early as possible. It is firstly faced with the separation, purification, preparation and structural identification of main flavonoids in EBL. In this studies, using high-speed countercurrent Chromatography (HSCCC) to pre-purify flavonoids in Eblg?!, preparative high performance liquid Chromatography (PHPLC) to prepare monomers, and HPLC-MS to identify structure, we gained two pure chemicals of C-glycosyl flavonoids of bamboo. At the same time, the measurement of trace elements in Eblgyi was also conducted using by 1.5th Differential Stripping Voltammetry. Results were reported as follows, respectively.1) Through investigating the distribution coefficient, delamination time, and volume ratio between two phases of six solvent systems, one mix-solvents that consists of petroleum, n-butanol and water (1:4:5, v/v) was selected for HSCCC. Its delamination time is 25s, volume ratio between upper and nether phases was 0.96. And the distribution coefficients of two main C-glycosyl flavones of bamboo in the mix-solvents were 3.80 and 4.44, respectively.2) Taking the upper of the mix-solvents as stationary phase and the nether as mobilephase, six eluted fractions, which include a part stayed in stationary phase, were obtained by HSCCC in 3 hours. The separating conditions were 800rpm rotate speed, 2.25ml/min flow rate, and 103 mg injection amount of Ebl971 sample. Two main C-glycosyl flavones were detected by HPLC in the fifth fraction, i.e. the biggest peak.3) The fifth fraction was purified by PHPLC under following condition: column temperature 30 C, flow rate 1.0 ml/min, injection volume 100uL, UV detection wavelength 330nm, and PDA detection wavelength 190-600nm. Two flavonoid monomers were prepared and both have the character UV absorbance. Their bandI and band II were located in the ranges of 300~400nm and 240~285nm, and absorbance intension also accords w ith the characteristic of flavonoids.4) The chemical configuration of two monomers was identified by HPLC-MS technology. Results showed that they all have the same molecular weight of 448, with same band I and different band II absorbance. Comparing with the standard samples bought from of America Indofinechemical Company, and testing by standard addition method of HPLC, two monomers were approved as orientin (8-C-glucosyl-luteotin) and isoorientin (6-C-glucosyl-luteolin), individually.5) Determination of trace elements of Cd, Pb, Zn, Cu by the 1.5th differential anode stripping voltammetry were conducted too. In the solvent medium of 0.01mol/L Potassium hydrogen tartrate and 0.045mol/L NaAc with pH5.78, all of four irons can produce very sensitive oxidation waves. The peak height is related linearly with iron concentration in the range of 10-8-10-6mol/L. This method has been successfully used to inspect the content of Cd, Pb, Zn and Cu of Ebl971, and results showed Pb at (1.69+0.06)ug /g and Zn at (6.09+0.57)ug /g in dry base. Method's variation coefficients were 3.38% and 9.31%, and the recovery rates were 84.7-108% and 85.2-105%, respectively. However, Cd and Cu in Ebl971 could not be determined here, due to their contents over the inspecting limit of thismethod.These studies revealed that the flavone glycosides in EBL could be separated and purified above 0.1g scales by HSCCC plus HPLC fast and effectively. It explored an effective route to prepare bamboo-leaf-flavonoid standards and settled down a foundation for setting up a high-standard quality assurance system of EBL. Meanwhile, the method application of the anode stripping voltammetry in continuous determination of trace amoun...
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