UV-B对两种藻光合色素和多糖含量的影响

本文研究了微绿球藻(Nanochloropsis sp.)和海洋原甲藻(prorocentrum micans)在不同辐射强度的UV-B照射下的光合色素和多糖含量的变化，结果表明微绿球藻比原甲藻有更强的抗紫外辐射能力。它的叶绿素a含量在UV照射下保持相对稳定，而原甲藻的叶绿素a含量明显下降。同时发现微绿球藻中的类胡萝卜素含量有十分显著的上升，由于类胡萝卜素具有保护功能，因此它很可能保护了叶绿素a免遭破坏，从而在微绿球藻的抗紫外辐射中起到重要作用。另外，紫外处理也促进了微绿球藻中多糖含量的升高，这也有利于提高它的抗UV能力，多糖可能作为一种保护机制，对保护藻类防止UV伤害方面有一定功能。原甲藻则因为这些机能较弱，对UV的抗性较低。

Effects of different intensity of UV-B irradiation enhancement on photosynthetic pigments and polysaccharide content in two algae

The effects of different intensity of UV-B irradiation enhancement on photosynthetic pigments (cholophyll a and carotenoids) and polysacchride content were studied in Nanochloropsis sp. and Prorocentrum micans. Results proved that Nanochloropsis sp. is higher in UV resistance than Prorocentrum micans. Chla content in Nanochloropsis sp. mantained stable relatively during UV-B treatment, while Chla content in Prorocentrum micans decreased obviously. On the other hand, the lower dosage of UV-B induced a marked increase in carotenoids content for Nanochloropsis sp., which may protect Chla from damage, hence played an important role for Nanochloropsis sp. in resisting of UV-B enhancement. Moreover, polysaccharide content in Nanochloropsis sp. increased during UV-B treatment. It indicated that polysaccharide may have some functions against UV-B. Prorocentrum micans showed more sensitive to UV-B enhancement, consistent with its weaker functions.