Study On Tea By Dual-Index Sequence Analysis Method For ~1HNMR Fingerprint Spectra And SEM Observation Of Leaf Epidermis

As a kind of healthy beverage and fashionable the world, tea is one of the three most important beverages in the world. Tea has many functions, such as promoting fluid relieving thirst, diuresis, removing toxin, antibacterial, anti-cancer and lipid-lowering. Its health function and medical mechanism have attracted many scientists' attention. Current studies of tea are mostly targeted chemical components analyses and determinations. The results can not reflect the inherent cooperation, efficacy and stability of tea. Therefore, analysis of comprehensive quality of tea is the inevitable tendency in the modern society.It is difficult to make clear all the complicated ingredients of the tea. If only taking a certain or several active (effective) ingredients as quality controlling index, it is not enough. Fingerprint spectra technique depends on the development of the modern analysis technology. It reflects the whole components information of the natural drugs but not confines to the content of a certain ingredient and is considered to be the symbol of modernization of quality control of natural drugs, integrity and fuzziness are the basic characters of the fingerprint spectra of natural drugs. ~1HNMR fingerprint spectra is investigated by dual-index sequence analysis method of common and variant peak ratio in this thesis, using the information of the tea to build multivariate space and to improve resolutions of analytical method and to set up scientific and reasonable multi-identification method, it reflects the integrity and individual difference of samples and therefore it is high reliability. This method can systematically solve discriminate the genus of tea, efficiency and quality of drugs and so on.The thesis consists of four parts:The first section introduces the importance of the study of tea, and explains the advancement of dual-index sequence analysis method of common and variant peak ratio study on ~1HNMR fingerprint spectra in discriminate the genus of tea and the quality control and differentiating function by using SEM in the observation of leaf epidermal characters to classification of the genus.The second section explains the reason why choose green tea and black tea to study and the distilling condition: under room temperature when distill by supersonic with 60% ethanol for 45 minutes and the preparation of tea extracts.The third section discusses that the ~1HNMR has the characteristics of the fingerprint spectra. It has a well corresponding relation between the fingerprint spectra and the genus of tea. ~1HNMR can be used in the genus differentiation and the study on chemical constituents. Dual-index sequence analysis method of common and variant peak ratio had been used in ~1HNMR fingerprint spectra of tea extracts to distinguish genus from the similarity discrepancy. It is concluded that in the range of 8.65ppm-4.97ppm, whether taking Longjing or other green or black tea as referent samples, it is clear that the same genus of tea has similar quality and Longjing tea has highly similarity with green tea. Longjing and other green tea have low similarity with black tea. Therefore they can be discriminated integrally and partially. Longjing is a famous brand in green tea. And they are different genus with black tea. Japanese green tea could be distinguished with china tea. The entire spectra could not be used to reflect quality difference of the genus of tea in ~1HNMR fingerprint spectra. When green tea as referent sample, it keeps greatest proportion in similarity in its genus. It is shows that it can be discriminated that green tea and black tea belongs to different genus in the entire spectra.The fourth section shows that leaf epidermal and stomata characters of tea are observed with scanning electron microscope (SEM). The results show that the leaf epidermis of Longjing, green and blank tea look like smooth, irregular regulate-ripple or rough and the stomata density are difference. But the shapes of inner margin of outer stomata ledge are contractile, round, elliptic or sinuate. The differences on leaf epidermal stomata characters provide a new evidence for the identification of the genus.The chief characteristics of this thesis are as follows:1. ~1HNMR fingerprint spectra of tea is investigated by dual-index sequence analysis method of common and variant peak ratio in this thesis. It can not only reflect the integrity of the sample but also the individual difference and therefore it is high reliability. 2. The leaf epidermal and stomata characters of tea are observed by using SEM, and in order to provide new scientific basis for identifying species. It is of high reference value for the classification of the tea in the genus. And combining the above analysis. The results are more persuasion.