Karonen Maarit, Ossipov Vladimir, Ossipova Svetlana, Kapari Lauri, Loponen Jyrki, Matsumura Hideyuki, Kohno Yoshihisa, Mikami Chikako, Sakai Yasuko, Izuta Takeshi, Pihlaja Kalevi
Laboratory of Organic Chemistry and Chemical Biology, Department of Chemistry, University of Turku, Finland.
J Chem Ecol. 2006 Jul;32(7):1445-58. doi: 10.1007/s10886-006-9061-8. Epub 2006 May 23.
Proanthocyanidins (PAs) or condensed tannins are a major group of phenolic compounds in the leaves of birch trees and many other woody and herbaceous plants. These compounds constitute a significant allocation of carbon in leaves and are involved in plant responses to environmental stress factors, such as pathogens or herbivores. In some plants, PA concentrations are affected by atmospheric carbon dioxide (CO(2)) and ozone (O(3)) levels that may influence, for example, species fitness, community structure, or ecosystem nutrient cycling. Therefore, a study on the quantitative response of PAs to elevated concentrations of carbon dioxide (CO(2)) and ozone (O(3)) was undertaken in seedlings of Betula platyphylla, Betula ermanii, and Fagus crenata. Seedlings were exposed to ambient or elevated O(3) and CO(2) levels during two growing seasons in the Kanto district in Japan. Ten open-top chambers were used for five different treatments with two replicates: filtered air (FA), ambient air (ambient O(3), 43 ppb; ambient CO(2), 377 ppm), elevated O(3) (1.5 x ambient O(3), 66 ppb), elevated CO(2) (1.5 x ambient CO(2), 544 ppm), and elevated O(3) and CO(2) combined. In addition, seedlings growing in natural conditions outside of chambers were studied. Leaf samples were analyzed for total PA concentrations by butanol-HCl assay and for polymeric PA concentrations by normal-phase high-performance liquid chromatography. Total PA concentrations in leaves of all species were similarly affected by different treatments. They were significantly higher in seedlings treated with elevated CO(2) and O(3) combined, and in seedlings growing outside chambers compared with the FA controls. F. crenata contained only traces of polymeric PAs, but significant species x treatment interaction was observed in the polymeric PA concentrations in B. ermanii and B. platyphylla. In B. platyphylla, leaves treated with elevated CO(2) + O(3) differed significantly from all other treatments. It was suggested that the strongest effect of elevated CO(2) and O(3) combined on leaf PA contents resulted from the additive effect of these environmental factors on phenolic biosynthesis.
原花青素（PAs）或缩合单宁是桦树以及许多其他木本和草本植物叶片中主要的一类酚类化合物。这些化合物在叶片中占据了相当一部分的碳分配，并参与植物对环境胁迫因子（如病原体或食草动物）的响应。在一些植物中，原花青素的浓度会受到大气二氧化碳（CO₂）和臭氧（O₃）水平的影响，而这些水平可能会影响，例如，物种适应性、群落结构或生态系统养分循环。因此，对白桦、岳桦和日本花楸幼苗中原花青素对二氧化碳（CO₂）和臭氧（O₃）浓度升高的定量响应进行了研究。在日本关东地区的两个生长季节中，将幼苗暴露于环境或升高的O₃和CO₂水平下。使用十个开顶式气室进行五种不同处理，每种处理重复两次：过滤空气（FA）、环境空气（环境O₃，43 ppb；环境CO₂，377 ppm）、升高的O₃（1.5倍环境O₃，66 ppb）、升高的CO₂（1.5倍环境CO₂，544 ppm）以及升高的O₃和CO₂组合。此外，还研究了在气室外自然条件下生长的幼苗。通过正丁醇 - 盐酸法分析叶片样品中的总原花青素浓度，并通过正相高效液相色谱法分析聚合原花青素浓度。所有物种叶片中的总原花青素浓度受到不同处理的影响类似。与FA对照相比，在同时接受升高的CO₂和O₃处理的幼苗以及在气室外生长的幼苗中，总原花青素浓度显著更高。日本花楸仅含有痕量的聚合原花青素，但在岳桦和白桦的聚合原花青素浓度中观察到显著的物种×处理相互作用。在白桦中，接受升高的CO₂ + O₃处理的叶片与所有其他处理有显著差异。研究表明，升高的CO₂和O₃组合对叶片原花青素含量的最强影响是由于这些环境因子对酚类生物合成的叠加效应。
