Stefi Aikaterina L, Nikou Theodora, Vassilacopoulou Dido, Skaltsounis Leandros-Alexios, Halabalaki Maria, Christodoulakis Nikolaos S
Department of Botany, Faculty of Biology, National and Kapodistrian University of Athens, 15701, Athens, Greece.
Division of Pharmacognosy and Natural Products Chemistry, Department of Pharmacy, National and Kapodistrian University of Athens, 15771, Athens, Greece.
Planta. 2021 Feb 18;253(3):70. doi: 10.1007/s00425-021-03588-2.
The quantitative profile of the biochemicals secreted by summer and winter leaves, present noticeable differences and appear to be qualitatively different from the biochemical profile of the commercially valuable mastic. The anatomy of the root and the primary and secondary shoot as well as that of the summer and winter leaves of P. lentiscus was thoroughly investigated. The secreting network was tracked throughout the plant axis, from the root to the leaves, and the active secreting cells of the duct epithelium were localized, while the secondary metabolites produced within the cells of the summer and winter leaf tissues were identified histochemically. Numerous phytochemicals were identified in the leaf extracts with UHPLC-qTOF MS analysis. The analyzed extracts from summer and winter leaves displayed similar qualitative profile, although quantitative differences were evident, since, during the summer, the leaves tend to synthesize the more complex amongst the identified compounds. The phytochemical profile of the leaf extracts turns to be completely different compared to that of the valuable mastic harvested from the injured trunks. Many of the compounds common in mastic were not detected in the analyzed leaves samples. The numerous secreting ducts either fail to form a unified network, so composition of the secreted material varies in the different organs of the plant or they compose a continuous network, but the biochemical profile of the secreted material differs along the plant axis. Such a detailed investigation of the secretion network of the mastic tree may assist the improvement of the yield and promote the production of valuable phytochemicals through in vitro cultures.
夏季和冬季叶片分泌的生化物质的定量特征存在明显差异，并且在质量上似乎与具有商业价值的乳香的生化特征不同。对乳香黄连木的根、初生和次生枝条以及夏季和冬季叶片的解剖结构进行了深入研究。追踪了从根到叶贯穿整个植物轴的分泌网络，定位了导管上皮的活跃分泌细胞，同时通过组织化学方法鉴定了夏季和冬季叶片组织细胞内产生的次生代谢产物。通过超高效液相色谱-四极杆飞行时间质谱分析在叶片提取物中鉴定出了多种植物化学物质。夏季和冬季叶片的分析提取物显示出相似的定性特征，尽管定量差异明显，因为在夏季，叶片倾向于合成已鉴定化合物中更复杂的化合物。与从受伤树干收获的珍贵乳香相比，叶片提取物的植物化学特征完全不同。在分析的叶片样品中未检测到乳香中常见的许多化合物。众多的分泌导管要么未能形成统一的网络，因此分泌物质的组成在植物的不同器官中有所不同，要么它们构成一个连续的网络，但分泌物质的生化特征沿植物轴不同。对乳香树分泌网络进行如此详细的研究可能有助于提高产量，并通过体外培养促进有价值的植物化学物质的生产。
