| The microorganisms which can survive in extreme environment certainly own some special character, the common microorganisms don't have during long period of opposition and adaptation to extreme environment. Therefore, they have given rise to people's great attention since 1970's, and it becomes one of hot research fields. It is of not only greatly theoretical value to understanding life extreme, evolution and classification of microorganism by studying on extreme microorganism, but also important practical value to prevention and cure of environment pollution, reconstruction of environment and exploitation of new function of microorganism. As a matter of fact, Antarctic ice microalgae belong to one of extreme microorganisms with special character.Antarctic ice microalgae are one of main producer of primary production in marine ecology system of Antarctic pole region, they take up important status and play important role in Antarctic ecology system. With ozone destroyed seriously, influences of ultraviolet on ecology give rise to people's great attention. It is confirmed that UV-B is obviously harmful to algae, and the harmful aims are protein, DNA, and photosynthetic pigment, and so on. Meanwhile, algae have certain ability to adapt itself to UV-B enhancement. Especially, Antarctic ice microalgae, which live in strong UV-B irradiation environment under ozone hole of Antarctic region, have strong ability against UV-B irradiation. However, any more little UV-B enhancement will result in great influence on Antarctic ice microalgae, because there have been already strong UV-B irradiation in Antarctic. Consequently, take Antarctic ice microalgae as research target, we can understand its response to UV-B enhancement, influence and adaptation mechanisms of UV-B enhancement, composition and molecule structure of its active substances.In order to get up above aims, author isolated twenty species of Antarctic ice microalgae(their name showed in Tab.2.2) in five different phylum from Antarctic seawater and Antarctic ice samples. Then, according to different experimental aims, some representative algae species were selected and studied. The results are as follow.1. Two common methods of isolation and purification of microorganisms were improved so that they were suitable to be applied to Antarctic ice microalgae. Anyhow, twenty species of Antarctic ice microalgae in five different phylum, including fifteenspecies of Diatoms, two species of chlorophyceae, one species of Cyanophyceae, one species of Dinophyceae, one species of Chrysophyceae. Diatoms are superior species, while Cyanophyceae, Dinophyceae and Chrysophyceae are not easy to be gotten, because they are inferior species in Antarctic. Moreover, Cyanophyceae is discovered a second time in Antarctic seawater, which supports JANG Ying-hui's conclusion that there is Cyanophyceae in Antarctic region. Two methods combined with each other are very effective to the isolation of Antarctic ice microalgae. Compared with each other, capillary method can isolate Antarctic ice microalgae successfully at one time, and Antarctic ice microalgae grow more quickly; while plate method is simple and easy. Two methods of purification are applied to Antarctic ice microalgae. Only the method of UV irradiation is suitable to purification of Antarctic ice microalgae, but the method of antibiotics is not. Observation of 20 species of morphology of Antarctic ice microalgae is discovered that Antarctic ice microalgae get together closely by community, with good shape of geometry. In addition, it is maybe a survival mechanism against cold, high salinity and strong UV irradiation. In conclusion, tolerance to UV irradiation and symmetric geometric shape of Antarctic ice microalgae community are adaptive to Antarctic environment.2. In experiment, Antarctic ice microalgae grow more slowly than other common marine algae. Magnesium glycinate (Mg-Gly) as a new growth promoter was used in Antarctic ice microalgae (Biddulphia sp. H-1 and Pyramidomonas sp. L-1) culture, and it was tested to...
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