Tissue Culture Of Anji White Tea And Its Tea Polyphenols

Anji Baicha is a stable genetic albino mutant variety of Camellia sinensis, which is originated in Anji County, Zhejiang Province. And it has been introduced to Jiangsu, Jiangxi, Henan, Sichuan, Chongqing, Guizhou and some other places. The new shoot Anji Baicha is very sensitive to high temperature, drought, low temperature, strong light irradiation at stage albinism in spring, so it is very difficult to grow it in other areas on a large scale. Because of the limited picking time and low production, the demand of Anji Baicha always exceeds supply. Consequently, the research of Anji Baicha can provide basic data and technical support for the development of the Anji Baicha.In this study, leaves of Anji Baicha are used as explants, studied the best induction and proliferation conditions of callus and the optimum plant growth regulator and concentrations in accumulation of tea polyphenolss in callus. In addition, the study determined the antioxidant activity of methanol extracts from callus cultured in different conditions and analyzed the chemical composition by GC-MS. The results are as following:1. The most suitable medium in callus induction is MS+TDZ1.0mg/L, with 90.21% callus induction rate,which appears to be red and little green, loose, vigorous growth, advantageous to subculture.2. The most suitable medium for callus proliferation is MS+TDZ0.5mg/L+IAA1.0mg/L, on which it can multiply 16.89 (fresh weight) and 20.75 (dry weight) after 45d. The best harvest time of callus is 45d, and showed an "S" type.3. The most suitable medium for accumulation of tea polyphenols in callus is MS+TDZ0.5mg/L+IAA1.0mg/L. Besides, The addition of phenylalanine in the culture medium, it can facilitate the accumulation of tea polyphenols, the optimum concentration of phenylalanine is 0.5mg/L.4. The antioxidant activities are evaluated by testing the clearance rates of DPPH, ABTS and ·OH. The results show that:the ICso of the clearance rates of DPPH, ABTS and ·OH of each sample extractions have negative correlation with the content of tea polyphenols. The correlation coefficients are-0.698 (DPPH),-0.688 (ABTS),-0.756 (·OH). The extractions of callus cultured in MS+TDZ0.5mg/L+IAA1.0mg/L eliminate DPPH and ·OH more strong than cultivar, but eliminate ABTS less strong than cultivar.5. This study analyzed chemical constituents of methanol extracts from callus cultured in different medium.70 compounds are identified and most of them are amino acids, polyphenols, sugars, esters, carboxylic acids, alcohols, amines, alkaloids.The abundance and the content of each component in the extracts are more than cultivars. The content of each sample have large difference ranging from 26 to 40. Epicatechin are detected in 12 samples and sinapic acid are detected in 12 samples.