| Pu'er tea, made of Camellia sinensis (Linn.) var.assamiea (Masters) Kitmaura, distributed only in Yunnan province, with special fermentation process, is a special tea of China. Pu'er tea, with a lubricous taste, has the functions of reducing blood fat, lowering blood pressure, antibacterial, helping digestion, and detoxification and various health care effects. In addition, it also has a strong cultural foundation, thus it becomes more and more popular among the consumers, and has been recognized as a green healthy drinks. It is mainly produced in Yunnan province. Besides, there is a distribution in Guizhou, Guangxi, Fujian, Guangdong and Hainan provinces. Lincang, Pu'er and Xishuangbanna in Yunnan province is thought to be the origin. With the development of Pu'er tea industry, there are more and more imitation and inferior issues in Pu'er tea markets. Quality differences exist between Pu'er tea from different areas, different manufacturers, different brands, which seriously affect the healthy development of Pu'er tea market and the industry. Based on a sufficient investigation of the production places and markets of Pu'er tea, those from five different area, including Honghe, Xishangbanna, Dalixiaguan, Simao and Lincang, those of different storage time, that is 1 year and 3 years, and those of different processing technology, that is crude and processed, were chosen in this thesis. To determine the effects of different origin, different storage time and different processing technology on quality of Pu'er tea, their contents of total flavonoids, total polysaccharides and other active components were investigated, and their antioxidant activity, antifungal acitivity and reducing blood lipid activity were tested and compared. The main results were as follows:1. Along with the expansion of Pu'er tea market, its production areas also extend to the peripheral areas of origins. So far, there has been a large distribution of Pu'er tea in Honghe, Xishuangbanna, Dali, Simao, Lincang and other places. After years of development, Pu'er tea has been exported to Hong Kong, Macao, Taiwan, Southeast Asia and other countries around the world. And a number of well-known brands has formed, such as Jixing, Dayi, six big tea hill, and so on. But at present, there are a variety of shoddy, fake and bad ones in the Pu'er tea market to cheat customers, which has seriously affected the healthy development of Pu'er tea industry. To elucidate the effects of different origin, different storage time and different processing technology on tea quality impact from a theoretical point of view is urgent. 2. Pu'er tea produce in the five different areas including Honghe, Xishuangbanna, Dalixiaguan, Simao and Lincang were chosen, NaNO2-Al(NO3)3 method was used to determine the content of total flavonoids, sulphuric acid phenol method was used to determine the content of total polysaccharides, HPLC method was used to determine the content of gallic acid, caffeine and (+) catechins, it was found that Pu'er tea from Honghe was lowest in polysaccharide content, and highest in the content of caffeine and (+) catechins, that was respectively 4.33%,37.66 mg/g and 0.49 mg/g. That from Xishuangbanna was highest in the content of total flavonoids, that was 5.94%. That from Dalixiaguan was highest in the content of total polysaccharides and galic acid, that was 6.18% and 15.12 mg/g, respectively. That from Simao was lowest in the contents of total flavonoids, caffeine, galic acid and (+) catechins, that was 2.93%,24.76 mg/g,2.78 mg/g and 0.49 mg/g, respectively. The content of all components of Pu'er tea from Lincang were in the middle. DPPH method was used to compare the antioxidant activity of different origin, and it was found there were certain differences among different origins. And the result was Dalixiaguan> Xishuangbanna> Lincang> Honghe> Simao. MIC method was used to compare the antifungal activity of different origin, and it was found there were large differences among different origins. That from Dalixiaguan had the strongest antifungal activity and broad antifungal spectrum, that from Simao and Lincang had rare antifungal activity, while that from Honghe and Xishuangbanna had the moderate antifungal activity. Hyperlipidemia mice model induced by high fat feed was used to compare their hypolipidemic activity, and it was found their hypolipidemic activity were equal. Although there were some differences among their contents of active components, all tested pharmacological activities of them were equal. It is proved there were no quality difference among the Pu'er tea from Honghe, Xishuangbanna, Dalixiaguan, Simao, and Lincang.3. Pu'er tea of 1 year storage time and 3 years storage time from Honghe were chosen, NaNO2-Al(NO3)3 method was used to determine the content of total flavonoids, sulphuric acid phenol method was used to determine the content of total polysaccharides, HPLC method was used to determine the content of gallic acid, caffeine and (+) catechins. It was found that Pu'er tea of 3-year storage was higher in the content of total flavonoids and lower in the contents of total polysaccharides, caffeine, and (+) catechins than that of 1-year storage, while their content of galic acid was equal. DPPH method was used to compare their antioxidant activity of different origin, and it was found that the antioxidant activity of Pu'er tea of 1-year storage was much stronger than that of 3-year storage. MIC method was used to compare the antifungal activity of different origin, and it was found that both of them had no effect on Candida albicans and Phytophthora nicotianae, they had equal effect on Wheat red mildew, and Pu'er tea of 1-year storage had stronger effect on Tomato gray mould blight fungus than that of 3-year storage. Hyperlipidemia mice model induced by high fat feed was used to compare their hypolipidemic activity, and it was found there were no significant difference between their hypolipidemic activity, although most the index of Pu'er tea of 3 year storage were better. The chemical components of Pu'er tea changed a lot during the storage. With the extension of storage time, the content of total flavonoids increased, the contents of total polysaccharides, caffeine and (+) catechin decreased, while the content of some components such as gallic acid did not change significantly. Due to the variation of chemical composition, there were certain difference among their pharmacological activities. The antioxidant activity decreased and hypolipidemic activity increased along with the increation of storage time.4. Both crude and processed Pu'er tea of 3 year storage time from Honghe were chosen, NaNO2-Al(NO3)3 method was used to determine the content of total flavonoids, sulphuric acid phenol method was used to determine the content of total polysaccharides, HPLC method was used to determine the content of gallic acid, caffeine and (+) catechins, it was found that there were significant difference in their active components and their proportion. After procession, the contents of total polysaccharides and galic acid increased at an extent, while the contents of total flavonoids and (+) catechins decreased significantly. DPPH method was used to compare their antioxidant activity, and it was found that the antioxidant activity of crude Pu'er tea was much stronger. MIC method was used to compare the antifungal activity, and it was found that the crude Pu'er tea had stronger antifungal activity and broad antifungal spectrum. Hyperlipidemia mice model induced by high fat feed was used to compare their hypolipidemic activity, and it was found there were no significant difference between their hypolipidemic activity, however, most the index of processed Pu'er tea were better. 5. Infrared absorption spectrometry was used to compare the infrared absorption spectral differences of Pu'er tea of 5 different origin,2 different storage times and 2 different processed technologies, it was found that there were certain difference in the IR fingerprint spectrum of Pu'er tea of different sources. Producing area, storage life and process technology could be identified through the special region and special absorption in the IR fingerprint spectrum. IR fingerprint spectrum has a certain value in the quality supervision of Pu'er tea, and further study is needed for the establishment of the specific method.The main innovations of this thesis are as follows:(1) the first hand information of the development of Pu'er tea industry was achieved through the survey of the origin and market of Pu'er tea. (2) A variety of chemical analysis methods and multiple pharmacological models were used to compare the chemical constituents and pharmacological activities of Pu'er tea of different origins, different storage years, different processing technology, and the effect of each factor on the quality of Pu'er tea was system evaluated. (3) The results and data of this study provided important experimental basis for the health development of Pu'er tea industry.
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