| Yunnan Pu'er tea is producted only in chinese,it is best-selling in domestic and foreign markets. It's has much health function, such as hypolipidemic, slimming, anti-arteriosclerosis, anti-cancer, protect stomach, anti-aging and many other health effects.Yunnan Pu'er tea is a fermentation tea which is producted by a large-leaved coarse tea through post-fermentation and artificial solid-state fermentation. The chemical substances are occurred a series of significant changes in the post-fermentation process to form the unique style and quality of health care functions, and its hypolipidemic effect was particularly marked. The major Hypolipidemic components are tea polyphenols, tea polysaccharide, tea pigments and lovastatin in Pu'er tea.In this paper, the best extraction conditions of tea polyphenols,tea polysaccharide and lovastatin are confirmed by experiments, then they are detected by different methods. The reasons that their contents are difference in various kinds of tea are explored in the end.Tea polyphenols are extracted by the ethanol of 75%. The best experimental extraction conditions of catechins and gallic acid is that the sample is treated by ethanol extraction for 90min and 120 min. The catechins and gallic acid in the leaching solution are detected by high-performance liquid chromatography with C18 column. The mobile phase is water:methanol:acetic acid (74:24:2, v/v /v), flow rate is 1mL/min, the column temperature keeps at 30℃. The content of catechins in various kinds of tea is green tea>black tea>Pu'er tea and gallic acid is Pu'er tea>black tea>green tea.The best extraction conditions of tea polysaccharide is that the sample is treated by water extracting for 75min. The tea polysaccharide in the leaching solution is detected by UV-Vis spectrophotometry and wavelength is 490nm. The content of tea polysaccharide in various kinds of tea is: Pu'er tea> black tea> green tea.In this paper, the high-performance liquid chromatography separation determination conditions of lovastatin in Pu'er tea is founded. The mobile phase is methanol-water(80:20,v/v), flow rate is 1mL/min, the column temperature keeps at 30℃.We inject 20μL and detect at 237nm.The results reveal that the main peak and impurity peak are well seprated.The calibration point is linear in the concentration range from 9.8μg/mL to 78.4μg/mL(R2=0.995), the accuracy and precision are good, extraction recovery is stable around 98.18%.Pu'er tea pretreatment—hydrolysis of lovastatin and solvents volatilization have great impact on testing of lovastatin. Lovastatin in Pu'er tea is extracted by ultrasonic extraction for the first time in this paper. This new method is better than the traditional extraction method. The best experimental extraction conditions of lovastatin is that the sample is treated by ethyl acetate ,solid-liquid ratio was 1:20, temperature of 25℃, time for 10 minutes.In this paper, it is evaluated various kinds of tea based the detection of different types of tea, such as black tea and green tea and Pu'er tea etc.It shows that there is no lovastatin in black tea and green tea, lovastatin is a special component in ripe Pu'er tea. It maybe related to Pile-fermentation during Pu'er tea processing. The content of lovastatin in Pu'er tea is changed with producing area and types of Pu'er tea. The content of lovastatin in various kinds of Pu'er tea is: bowl tea>cake tea>brick tea>loose tea; Old leaves Pu'er tea>tender Pu'er tea>normal cuspal Pu'er tea; Menghai Pu'er tea>Xiaguan Pu'er tea>Yiwu Pu'er tea.
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