Collaborative Research: Mixture synergy in Piper imides, iridoid glycosides, and furanocoumarins

植物次生代谢物以协同方式作为昆虫威慑物的例子并不常见，许多研究集中在天然产品的药物应用上，其中活性是偶然的，而不是进化的反应。该项目将测试植物产品在阻止昆虫方面的协同作用，它们表面上已经进化出了这种活动。将在三个系统中测试由单一植物物种产生的混合物中的化合物之间的协同作用（组内协同作用）：胡椒属物种（胡椒科，胡椒目）的酰亚胺、长叶车前（车前草科，唇形科）的环烯醚萜苷和Pastinaca sativa（伞形科，伞形目）的呋喃香豆素。帝国胡椒和黑枝胡椒的酰亚胺在结构上与来自新枝胡椒和瘤枝胡椒的酰亚胺和酰胺非常相似，最近已显示其对广泛的昆虫具有协同作用。这项拟议的工作测试的普遍性，组内协同作用的酰亚胺和酰胺属胡椒。为了测试组内协同作用是否普遍适用于其他类别的天然产物，环烯醚萜苷类化合物（单萜糖苷）和呋喃香豆素将被检查，因为它们在结构上与Piper酰胺/酰亚胺以及彼此无关，并且这两类化合物在植物昆虫相互作用中具有良好的记录中心作用。有机和高分子化学计划支持两位化学家和一位生态学家，教授克雷格D。Dodson和Joseph L.梅萨州立大学物理与环境科学系的理查兹和李A.杜兰大学生态学和进化生物学系的戴尔说。该提案中概述的方法将为化学生态学，生物测定和统计分析提供新的方法。它将提供严格的测试的重要假设，如何类内化合物协同作用，以阻止昆虫。这项工作将有助于一个长期的目标，以确定是否抗草食动物协同作用是广泛的植物次生代谢产物。如果协同作用被发现是普遍和普遍的活性测试时，对生态相关的昆虫食草动物，那么它是一致的一般假设，植物进化出多种化合物作为协同防御食草动物和病原体。这些结果也与控制作物上昆虫的方式直接相关。这项工作将延续两位化学家和一位生态学家之间长达十年的成功合作。该合作涉及一所本科院校和一所研究型大学，并成功地培养了大量研究生和本科生。目前的提案包括资助一名研究生和12名本科生。学生将在生物学和化学方面得到广泛的培训，合作者将继续参与杜兰大学为这些学生提供的重要培训计划，如本科生研究经验（REU），美国生态学会少数民族种子计划，路易斯安那州少数民族参与联盟，以及富布赖特的LASPAU计划培训来自其他国家的教师。

Examples of plant secondary metabolites acting in a synergistic fashion as insect deterrents are not common, and many studies focus on the pharmaceutical applications of natural products where activity is serendipitous and not an evolved response. This project will test for synergy between plant products in the deterrence of insects, the activity for which they have ostensibly evolved. Synergy between compounds in a mixture produced by a single plant species (intraclass synergy) will be tested in three systems: the imides of Piper species (Piperaceae, Piperales), the iridoid glycosides of Plantago lanceolata (Plantaginaceae, Lamiales), and the furanocoumarins of Pastinaca sativa (Apiaceae, Apiales). The imides of P. imperiale and P. melanocladum are structurally very similar to imides and amides from Piper cenocladum and P. tuberculatum which have recently been shown to act synergistically against a broad array of insects. This proposed work tests the generality of intraclass synergy for imides and amides of the genus Piper. To test if intraclass synergy is general to other classes of natural products, the iridoid glycosides (monoterpene glycosides) and furanocoumarins will be examined, since they are structurally unrelated to the Piper amides/imides and to each other, and both classes of compounds have a well documented central role in plant insect interactions.With the support of this linked collaborative award, the Organic and Macromolecular Chemistry Program is supporting the collaborative work of two chemists and an ecologist, Professors Craig D. Dodson and Joseph L. Richards, of the Department of Physical and Environmental Sciences at Mesa State College, and Professor Lee A. Dyer, of the Department of Ecology and Evolutionary Biology at Tulane University. The approach outlined in this proposal will provide novel methods for chemical ecology, bioassays, and statistical analyses. It will provide rigorous tests of important hypotheses on how intraclass compounds act synergistically to deter insects. The work will contribute to a long term goal to determine if antiherbivore synergy is widespread among plant secondary metabolites. If synergy is found to be general and widespread when testing for activity against ecologically relevant insect herbivores, then it is consistent with a general hypothesis that plants evolved multiple compounds as synergists for defense against herbivores and pathogens. These results are also directly relevant to the way insects are controlled on crops. The proposed work will continue a decade-long, successful collaboration between two chemists and an ecologist. The collaboration involves an undergraduate institution and a research university and has successfully trained a large number of graduate and undergraduate students. The current proposal includes funding for one graduate student and 12 undergraduates. Students will be broadly trained in both biology and chemistry, and the collaborators will continue to be involved with important training programs for these students at Tulane, such as Research Experience for Undergraduates (REU), the Ecological Society of America's SEEDS program for minorities, the Louisiana Alliance for Minority Participation, and Fulbright's LASPAU program for training faculty from other countries.