静止和充气培养条件下短期紫外辐射对钝顶螺旋藻光化学效率的影响  

SHORT-TERM EFFECTS OF SOLAR ULTRAVIOLET RADIATION ON THE PHOTOCHEMICAL EFFICIENCY OF SPIRULINA PLATENSIS IN NON-AERATED AND AERATED CULTURES

作　　者：吴红艳[1] 高坤山[2] 渡辉夫 

机构地区：[1]中国科学院水生生物研究所,武汉430072 [2]汕头大学海洋生物研究所,汕头515063 [3]海南迪爱生微藻有限公司,海口570102

出　　处：《水生生物学报》2005年第6期673-677,共5页Acta Hydrobiologica Sinica

基　　金：日本DIC海南微藻有限公司资助项目;国家自然科学基金项目(批准号:30070582)

摘　　要：为了研究短期太阳紫外辐射对钝顶螺旋藻的影响,作者将静止和充气培养的藻体,暴露在全波长太阳辐射PAB(PAR+UVA+UVB),去除UVB辐射PA(PAR+UVA)及切断所有紫外辐射的光合有效辐射P(PAR)三种光处理条件下,测定了其光化学效率的变化.结果表明,紫外辐射(UVP)及光合有效辐射(PAR)均能导致钝顶螺旋藻的光化学效率降低,表现出了明显的光抑制,但是,UVR可导致更大程度的光抑制.充气培养条件下,与早晨(07:00)初始值相比,PAR导致了11%～20%的光抑制,而UVR(PAB-P)所产生的额外光抑制占9%～31%;静止培养条件下,UVR的存在使得螺旋藻的光化学效率趋近于零(无法检出).在两种培养条件下,藻细胞所受最大光抑制均发生在中午,下午(17:00)表现出不同程度的恢复.紫外辐射使得类胡萝卜素及藻蓝蛋白与叶绿素a含量的比例增大.与PAB和P相比,PA处理使得螺旋藻类胡萝卜素和藻蓝蛋白与叶绿素含量之比明显升高,UVA可能会诱导类胡萝卜素及藻蓝蛋白的合成.Continuous depletion of the stratospheric ozone layer results in increasing solar ultraviolet radiation（UVR） reaching the earth＇s surface. Which has been considered to affect living organisms. Solar UVR may also affect a variety of physiological and biochemical processes in the economic cyanobacterium, Spirulina platensis. However,little has been documented on this aspect. The present study evaluated the short-term effects of UVR on photochemical efficiency of S. platensis in aerated and non-aerated cultures while exposing it to full-spectrum solar radiation（ PAB）, solar radiation depleted of UVB（PA） and solar radiation deprived of total UV（ P： PAR） . It was found that both UVR and PAR inhibited the photochemical efficiency during noontime（ 11：00-13：00）, however, UVR ＋ PAR（PAB）resulted in higher inhibition. In aerated cultures, PAR resulted in 11% -20% compared to the initial value in the morning （07：00）, UVR（PAB-P） brought about 9 % - 31% extra photoinhibition. While in non-aerated cultures, the photochemical effeiency could not be detected when exposed to UVR. The greatest inhibition was observed at noontime, and the recovery was achieved in late afternoon（ 17：00） in both the aerated and non-aerated cultures. UVR increased the ratio of carotenoids or phycocyanin to chlorophyll a. Compared with PAB and P treatments, cells exposed to PA showed higher values of the pigment ratios,lndicating a possibility that UVA may enhance the synthesis of carotenoids and phycoeyanin. Although S. platensis was negatively affected by UVR, it tended to develop mechanisms counteracting the damaging effects of UVR during this short-term exposure period, such as down-regulation of the photosynthetic activity of accumulation of the carotenoids.

关 键 词：太阳紫外辐射 钝顶螺旋藻 光化学效率 色素 

分 类 号：Q945.79[生物学—植物学]