SCREENING OF ULTRAVIOLET‐A AND ULTRAVIOLET‐B RADIATION IN MARINE GREEN MACROALGAE (CHLOROPHYTA) 1
SCREENING OF ULTRAVIOLET‐A AND ULTRAVIOLET‐B RADIATION IN MARINE GREEN MACROALGAE (CHLOROPHYTA) 1
复制标题
海洋绿藻（绿藻）中紫外线 A 和紫外线 B 辐射的筛查 1
DOI：
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发表时间：
2010
期刊：
影响因子：
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通讯作者：
W. Bilger
中科院分区：
文献类型：
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作者：
Frauke Pescheck;K. Bischof;W. Bilger
采用基于叶绿素荧光的体内检测技术，分析了海洋绿藻中大型藻类对紫外线的屏蔽能力。该方法最初用于评估高等植物叶片的表皮紫外线透过率，现已扩展到大型藻类。通过测量未受保护的样品(即来自六种藻类的分离的叶绿体)来验证该方法。结果表明，在所调查的71种绿藻中，只有40%和60%的绿藻对紫外线A(UVA)和紫外线B(UVB)有明显的屏蔽作用。一般说来，这些物种中的大多数筛选程度都很低。数据分析得到了一个清晰的系统发育模式，对特定物种的气候起源的影响很小。对于一些物种，可以在野外采集的样品和培养生长的样品之间进行比较。在现场收集的25种藻类中，只有11种的筛选效果明显高于在没有UVB辐射的情况下生长的藻类。首次证明了对枝角目的UVA和UVB进行非常有效的筛选。它们对UVB的屏蔽潜力在输入UVB辐射的40%到85%之间变化。然而，检测到的紫外线吸收化合物的性质和定位仍不清楚。长期的紫外光照射实验表明，紫外光屏蔽能力与紫外光诱导的光合作用效率抑制呈负相关。因此，具有明显屏蔽的物种比具有较低屏蔽的物种更耐紫外线。
Ultraviolet‐screening capacity of macrothalli from marine chlorophytes was analyzed using an in vivo technique based on chl fluorescence. The method, originally introduced to assess epidermal UV transmittance in leaves from higher plants, is extended to macroalgae. Validation of the method was obtained by measuring unprotected samples (i.e., isolated chloroplasts from six algal species). It is shown that in a total of 71 investigated green macroalgae, including cultured and field‐collected material from six systematic orders, only 40% or 60% displayed significant screening of ultraviolet‐A (UVA) or ultraviolet‐B (UVB) radiation, respectively. Generally, the extent of screening was low in most of these species. Data analysis resulted in a clear phylogenetic pattern with minor influence of climatic origin of a given species. For some species, comparison between field‐collected and culture‐grown samples was possible. Only in 11 of 25 species field collected algae had appreciably higher screening than those grown in the absence of UVB radiation. For the first time, very efficient UVA and UVB screening is demonstrated for the order of the Cladophorales. Their UVB‐screening potential varied between 40% and 85% of incoming UVB radiation. However, the nature and localization of the detected UV‐absorbing compounds are still unknown. Long‐term UV‐exposure experiments pointed to a negative correlation of UVB‐screening capacity and UV‐induced inhibition of photosynthetic efficiency. Thus, species with pronounced screening were more UV resistant than species with lower screening.