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杀虫剂的例子并不常见，许多研究集中在天然产品的制药应用上，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之间在威慑昆虫方面的协同作用，而昆虫表面上是为了这种活动而进化的。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(类内协同作用)：胡椒科(胡椒科，胡椒目)的酰亚胺，车前草属(车前科，胡椒目)的环烯醚萜糖苷，以及意大利面属植物(杏科，胡椒目)的呋喃香豆素。帝国拟青霉和黑枝拟青霉的酰亚胺类化合物在结构上与胡椒和根瘤拟青霉的酰亚胺和酰胺类化合物非常相似，最近发现这两种化合物对多种昆虫具有协同作用。这项拟议的工作测试了胡椒属酰亚胺和酰胺类内协同作用的一般性。为了测试类内协同作用是否普遍适用于其他类别的天然产品，我们将研究环烯醚萜糖苷(单萜糖苷)和呋喃香豆素，因为它们在结构上与胡椒酰胺/亚胺无关，而且这两类化合物在植物昆虫相互作用中都有很好的核心作用。在这一相关合作奖的支持下，有机化学和高分子化学计划正在支持两位化学家和一位生态学家的合作工作，这两位教授是梅萨州立学院物理和环境科学系的克雷格·D·道德森和约瑟夫·L·理查兹教授，以及杜兰大学生态和进化生物系的李·A·代尔教授。本提案中概述的方法将为化学生态学、生物分析和统计分析提供新的方法。它将对关于类内化合物如何协同作用以威慑昆虫的重要假设进行严格的测试。这项工作将有助于确定抗草食动物协同作用是否在植物次生代谢产物中广泛存在的长期目标。如果在测试对生态相关的昆虫食草动物的活性时，发现协同作用是普遍和普遍的，那么这与一个普遍的假设是一致的，即植物进化出多种化合物作为协效剂来防御草食动物和病原体。这些结果也与作物上控制昆虫的方式直接相关。这项拟议的工作将继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，并成功培养了一大批研究生和本科生。目前的提案包括资助1名研究生和12名本科生。学生将接受生物和化学方面的广泛培训，合作者将继续参与杜兰大学针对这些学生的重要培训计划，如本科生研究经验(REU)、美国生态学会针对少数族裔的种子计划、路易斯安那州少数族裔参与联盟以及富布赖特的LASPAU计划，以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.