Foutami Isa Jafari, Mariager Trine, Rinnan Riikka, Barnes Christopher James, Rønsted Nina
Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran.
Terrestrial Ecology Section, Department of Biology, University of Copenhagen, Copenhagen, Denmark.
Front Plant Sci. 2018 Dec 18;9:1877. doi: 10.3389/fpls.2018.01877. eCollection 2018.
Herbarium samples are increasingly being recognized for their potential in answering a wide range of research questions. However, the suitability of herbarium samples for chemical analysis is largely unexplored as they are thought to be too degraded. The aim of this study was to explore terpenoid profiles across time and geographic space for four medicinal species of across the Mediterranean to assess the suitability of using herbarium specimens in chemical analyses. Herbarium samples of , and collected over 150 years across the Mediterranean were compared to modern samples using both targeted and untargeted gas chromatography-mass spectrometry analysis of terpene profiles. There was no effect of collection year on chemical composition, although the total concentration of the 20 assessed standards and two individual standards significantly decreased over time. Instead, chemical profiles were defined by species, with strong species effects identified on both the targeted and untargeted chemical composition. Geographic variation was a factor in regulating the untargeted chemical compositions, suggesting some underlying environmental effects. However, there was no effect of sample altitude on either the targeted or untargeted chemical compositions. Chemical composition of four species are predominantly defined by species, and there was a substantially smaller effect of year of sampling. Given these results herbarium collections may well represent a considerably underused resource for chemical analyses that can benefit biodiversity and other studies.
植物标本越来越被认为具有回答广泛研究问题的潜力。然而，植物标本用于化学分析的适用性在很大程度上尚未得到探索，因为人们认为它们已经过度降解。本研究的目的是探索地中海地区四种药用植物的萜类化合物谱随时间和地理空间的变化，以评估在化学分析中使用植物标本的适用性。使用萜烯谱的靶向和非靶向气相色谱 - 质谱分析，将在地中海地区150多年间收集的、和的植物标本与现代标本进行比较。尽管20种评估标准品和两种单一标准品的总浓度随时间显著降低，但采集年份对化学成分没有影响。相反，化学谱由物种定义，在靶向和非靶向化学成分上均发现了强烈的物种效应。地理变异是调节非靶向化学成分的一个因素，表明存在一些潜在的环境影响。然而，样品海拔对靶向或非靶向化学成分均无影响。四种植物的化学成分主要由物种决定，采样年份的影响要小得多。鉴于这些结果，植物标本收藏很可能是一种未得到充分利用的化学分析资源，可为生物多样性和其他研究带来益处。
