| Tea is a kind of traditional natural drink and it is rich in selenium, zinc and other various trace elements. The nutrition of trace element and biological activity is closely related to its chemical form. Ethanol extracts and aqueous extracts of selenium enriched green tea have antioxidant and anticancer.Selenium, zinc and trace elements can be supplemented through drinking and at the same time play a role in health care. In addition, using ethanol, water extraction solvent to further process the selenium-enriched and zinc-enriched tea to develop natural antioxidants can open up a new way in producting bioactivator in terms of the selenium-enriched and zinc-enriched tea. In view of the current situation concerning the selenium, zinc and and their interaction on chemical forms having not been reported, this thesis focuses on the spraying of foliar application of selenium and zinc and researches on spraying of different concentration s of selenium, zinc and their proportions in different seasons and under different harvesting time the changing of three types of the chemical forms of selenium and zinc. The main findings are as follows:(1) Selenium, zinc and Selenium-zinc interaction effected on the contents and distribution of selenium of alcohol-soluble,water-soluble,salt-soluble. Take the spring tea as the example, the influence of one selenium treatment on spring tea displayed that the contents of selenium increased with the increase of selenium concentration. The selenium with 200μg/mL～400μg/mL had good effect on improving the contents of the three chemical form of selenium, especially when spraying selenium concentration achieved 200μg/mL, the three chemical forms of selenium increased most which meant the three chemical forms of selenium in tea were accumulated at a certain level. With the further improvement of selenium concentration, the selenium accumulation tended to stabilize. Of all the proportion of the total of alcohol- soluble Se was the highest, and water-soluble was higher than salt-soluble when the spraying concentration of Se alone. Under Single zinc treatment, the distribution of selenium of spring tea was less than the majority control. The three forms did not differ much, even no significant difference. The cumulative effect of selenium at 0.2%～0.4% of zinc treated with relatively clear, indicating that increased zinc concentration of three chemical forms of selenium on accumulation and distribution have little effect. The content of Se of three kinds of chemical forms was increased obviously when spraying apply Se at 200～400μg/mL and Zn was 0.4%～0.8%.The hightest content of Se of three kinds of chemical forms were 2.0428,1.1304,0.6365 mg/kg. Selenium levels from 200μg/mL up to 400μg/mL, and different levels of zinc ,three forms of concentration had little increased, even down to three kinds of chemical form is cumulative effect was to balance. Selenium-zinc interaction effected on the distribution of three forms were as follows:The alcohol-soluble Se in general was dominant, but the alcohol to the water-soluble Se transfer, especially in low-selenium (50μg/mL) with different concentrations of Zn ratio. There was no obvious difference of the proportion of the total of Se between alcohol-soluble and water-soluble when spraying 50μg/mL Se and the different Zn, or water-soluble were higher than alcohol-soluble. This indicated that selenium-zinc interaction sprayed on the tea with the ratio of three chemical forms of distribution, although there are similarities with the single selenium treatment, but as with zinc, especially in low-selenium (50μg/mL) and Zn. Of all the proportion of the total of alcohol-soluble Se was the higher, the water-soluble condition proportion also gradually enhances at the same time. As the selenium concentrations to 200～400μg/mL, and the zinc complex, the alcohol-soluble, water-soluble selenium in the proportion of the total than controls had different degree of increase, indicating 200～400μg/mL of selenium in the spraying of zinc in the combined application on the increasing of alcohol-soluble, water-soluble of selenium was also significant.In the spring but different picking time, the single selenium, zinc and interactive processing of single selenium showed declining trend with time protracted. Three kind of shapes also presented the varying degree shift.Selenium concentrations in 200～400μg/mL, and the zinc was 0.2%, the alcohol to the water soluble Se transfer after sprayinga 16 days and the water to the salt-soluble Se transfer after sprayinga 24 days. This indicated that we could have more the alcohol and water soluble Se after spraying 8 days. Single selenium, Single zinc and interaction to the effect of the summer, the autumn tea in different time were similar with spring tea. The Se content in ethanol soluble, water soluble, salt soluble of tea leaves was the highest in spring, and it was higher in summer than autumn.(2) Zinc, selenium and Selenium-zinc interaction effected on the contents and distribution of zinc of alcohol-soluble, water-soluble and salt-soluble. Take the spring tea as the example, the zinc had good effect on improving the contents of the three chemical form of zinc of spring tea, especially when spraying zinc at 0.4%～1.2%.When spraying zinc concentration achieved 0.4%, the three chemical forms of zinc increased most which meant the three chemical forms of zinc in tea were accumulated at a certain level., but With further increase of zinc concentration, an increase of reduced zinc accumulation stabilized. Selenium at 50～100μg/mL on three forms of zinc of spring tea increased significantly, the remaining selenium concentrations, the three kinds of forms of zinc had no significant increase compared with control. Combined applying concentration of Zn (0.4%～1.2%) and Se (100～200μg/mL) significantly increased the three kinds of chemical forms of zinc content, particularly zinc(0.8%) and Se (100～200μg/mL) were the best. The hightest content of Zn of three kinds of chemical forms were 61.83,170.63,157.51 mg/kg. Single zinc, selenium treatments alone, three quarters the ratio of tea chemical forms present water-soluble>salt- soluble> alcohol-soluble, but the interactive processing, salt-soluble zinc increase the proportion of state, water-solubl of zinc had the obvious transfer trend.Whether single or interactive processing facilities, three quarters of three forms of zinc content in tea leaves were picked as the time was decreased in different extent. Spraying Single selenium and Single zinc, the protracting of time does not influnce much on the distribution of three kinds of chemical forms of spring tea. There was no obvious difference of the proportion of the total of Zn between water-soluble and salt-soluble when spraying zinc and selenium at 50μg/mL,400μg/mL, the water to the salt-soluble Zn transfer. This indicated that time extended, with selenium to change the three chemical forms of selenium in the allocation of the water 1 to salt the soluble Zn transfer. we could have more water-soluble Zn after spraying 8 days.and 16 days. Single selenium, Single zinc and interaction to the effect of the summer, the autumn tea in different time were similar with spring tea. The Zn content in alcohol-soluble, water- soluble, salt-soluble of tea leaves was the highest in spring, and it was higher in summer than autumn.
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