【摘要】 采用两种微藻分离方法对本实验室在第18次南极考察采集的南极海冰和海水样品进行南极冰藻分离,得到包括1株南极蓝藻在内的8种南极冰藻。该蓝藻(南极蓝藻-B)的生长曲线表明,0～6 d有一个明显的延滞期,第6天进入对数生长期,第20天达到生长稳定期。紫外辐射增强后,南极蓝藻的形态和超微结构都发生了显著变化:细胞个体明显增大、细胞壁变厚、片层结构更加明显、多糖和脂肪颗粒数目增多。并发现了紫外辐射后的蓝藻向培养液中大量分泌物质的现象。这些现象表明,虽然南极地区紫外线辐射很强,但南极蓝藻可以产生多种抗紫外辐射的活性物质来适应这种极端环境。更多还原

【Abstract】 Eight strains of Antarctic ice algae, including a strain of Antarctic Cyanophyceae (Cyanophyceae-B ), were isolated using two methods from samples of sea water and sea ices collected on the eighteenth Antarctic exploration. The growth curve of Cyanophyceae-B showed that there was an obvious lag phage in the first 6 days.The log phage then began on the 6th day and on the 20th day the stationary phage was reached. After exposure to UV-B (70 μW/cm), both morphology and ultrastructure changed. Cells enlarged with the cell wall becoming thicker. The laminar structure became more visible and an increased number of polysaccharide and fat granules were seen. Furthermore, after UV-B radiation some Cyanophyceae cells were seen secreting material into the culture.These changes suggest the possible prescence of active substances in the cells of Antarctic Cyanophyceae-B able to resist UV-B radiation.更多还原