| Botanical extracts are extracted from plant using different organic solvents and vacuum-dried at different tempertures. Because of the effect of soil pollution, atmospheric environment pollution and self-metabolism, some harmful contents were also bioaccumulation in biotic fat during plant materials' growth. Although extracts contains main bio-active compounds, a few harmful constituents also exist in the extracts. Nowaday many analytical methods for determination of the harmful compounds in foods were proposed, but few methods are available for their detection in medicinal plant extract. So, it is significative to develop a series of analytical methods of the harmful compounds in herbal extracts. The efficient analytical method is a key to keep the safety of extracts. In this thesis, we concentrated ourselves on analysis of the harmful compounds in extracts by liquid chromatography and gas chromatography with different detector and developed their analysis methods, respectively. The studies included in this thesis are as follows:1. A method for analysis of benzopyrene in red clover extract by high performance liquid chromatography with spectrofluorescence detector was proposed. The sample was determinated by liquid chromatography using acetonitrile and water (70:30) as mobile phase, The excitation wavelength and emission wavelengh were 368 nm and 405 nm, respectively. The linear calibration curves was obtained in the range of 0.93～37.2 ng·mL-1, the resulted linear correation cofficient was higher than 0.992. The average recovery of benzopyrene was 85.2% . The method was convenient and accurate with good recovery.2. A multiresidue analytical method based on solid-phase extraction was developed for the simultaneous detection of 14 organochlorine pesticides (pentachlorobenzene, tecnazene, tetrachloroanilline, HCB, α-BHC,γ-BHC,β-BHC, pentachloroamlline,δ-BHC,. methyl-pentachlorophenyl sulfide (MPCPS), procymidone, p,p'-DDE, p,p'-DDD, o,p'-DDT) in ginseng extracts by GC-ECD. According to the result of analysis, we compared different technologies to remove the procymidone residue in ginseng extracts. At the same time, we monitored the ginsenosides in ginseng extracts before and after treatment. Results appproved that the removal technology of liquid-liquid extraction can remove 90% of the procymidone without ginsenosides loss in the treatment process.3. A headspace gas chromatography method for simultaneous determination of six residual solvents on red clover extract and Echinacea extract was set up. The result showed that the methed had good linear curves in the range of 0.0066～1.956 mg·mL-1 and average recoveries were higher than 97.61%. The new method was used for determination of residual solvents in commercial medicinal plant extracts. |
PDF Full Text Request