Structure and function of a new plant growth substance, lepidimoide.

在本研究中，我们从四个方面对新型化感物质来匹定的结构和功能进行了研究。研究结果如下：1)研究了化感物质来匹莫特在植物界的存在。在所研究的24种植物的分泌物中广泛存在Lepdimoide。2)通过下胚轴伸长实验研究了Lepidimoide及其类似物的构效关系。植物促生长活性的结构要求是α，β-不饱和羧酸上的糖醛酸衍生物通过α-葡萄糖苷键和糖醛酸中C-4，5位的双键键合在鼠李糖上。3)用高效液相色谱法和生物测定法测定发芽种子及其分泌物中来匹莫特的含量。萌发种子在吸胀后6h内开始渗出，4d内被降解和代谢。此外，吸收后还合成了部分渗出物。4)研究了利匹莫特对某些生理现象的影响。利培地莫特对叶绿素和5-氨基乙酰丙酸的合成有影响，并能抑制衰老(如衰老或脱落)。

In this research, we studied about the structure and function of a new allelopathic substance, lepidimoide at four other aspects. The results of this research are demonstrated as follows.1) The occurrence in the plant kingdom of the allelopathic substance, lepidimoide, was studied. Lepidimoide is widespread in the exudates from all plant species studied (24 species).2) The structure-activity relationship of lepidimoide and its analogues was investigated by means of Amaranthus hypocotyl elongation test. The structural requirements of lepidimoide for plant growth-promoting activities are the uronic acid derivatives on the alpha, beta-unsaturated carboxylate bonded to the rhamnose through an alpha-glucoside linkage and a double bond in the C-4,5 position in uronic acid.3) The contents of lepidimoide in the germinating seeds and their exudates were determined by HPLC and bioassay analysis during the germination period. The exudation of lepidimoide from germinating seeds began within 6 hr after imbibition and exuded lepidimoide degraded and/or metabolized within 4 days. Furthermore, a part of exuded lepidimoide was newly synthesized after imbibition.4) The effects of lepidimoide were studied on some physiological phenomena. Lepidimoide shows the effect for chlorophyll and 5-aminolevulinic acid synthesis and inhibition of aging (e.g.senescence or abscission).