芦荟属植物叶内蒽醌类物质的分布与其化学防御的关系

芦荟属植物是一类生长在干旱或半干旱沙漠环境的肉质植物，木立芦荟和海藻芦荟的肉质叶的植物研究结果表明，叶内含高浓度的芦荟素，高那特芦荟素，芦荟苦素和芦荟宁等蒽醌类物质，其中，海莱芦荟整叶的蒽醌类物质总含量占其泌出物干重的44．89％。两种芦荟叶内蒽醌类物质的分布有共同的规律，即幼叶的含量高于老叶；叶上部的含量高于中，基部，叶缘则高于叶的中央。但由于木立芦荟和海莱芦荟的个体形态不同，蒽醌类物质的分布在种间还存在各自的特点，根据实验结果推测，蒽醌类物质在芦荟属植物体内的累积和分布与其化学防御机制有关。

Distribution of anthraquinones in leaves of two Aloe species and their defence strategy

Aloe plants are the succulents mainly distributed in arid or semi arid desert in South Africa.TLC analysis indicated that Aole arborescens and Aloe hereroensis contained the high concentration of phenolic derivative metabolites, anthraquinones such as barbaloin, homonataloin, aloeresin and aloenin.In younger leaf, L3 of A.hereroensis , the average content of 4 anthraquinones reached 44.9% of the dry weight of exudates. The similar distribution of the anthraquinones in the two species were found, which showed that the youngest leaves had the highest content, the top part of each leaf had the highest content,and the basal part had the lowest content. Along leaf margin, the content was higher than that of central parts. However, some different distributions were also revealed and compared between the two species. It was inferred that the special distribution of anthraquinones in Aloe was a chemical defense strategy for protection themselves.