Sadgrove Nicholas J, Padilla-González Guillermo F, Telford Ian R H, Greatrex Ben W, Jones Graham L, Andrew Rose, Bruhl Jeremy J, Langat Moses K, Melnikovova Ingrid, Fernandez-Cusimamani Eloy
Jodrell Science Laboratory, Royal Botanic Gardens Kew, Richmond TW9 3DS, UK.
Botany and N.C.W. Beadle Herbarium, School of Environmental and Rural Science, University of New England, Armidale, NSW 2351, Australia.
Plants (Basel). 2020 Nov 13;9(11):1570. doi: 10.3390/plants9111570.
The highly aromatic Australian mint bushes from the genus Labill. produce a high yield of essential oil on hydrodistillation. Together with its rich history, horticultural potential, iconic flowers, and aromatic leaves, it achieves high ornamental and culinary value. Species in the genus express highly diverse and chemically unique essential oils that demonstrate intra- and inter-specific patterns that have inspired taxonomic reinterpretation for over a hundred years. Previous studies have conveyed that phenoplastic expression of volatiles creates chemotypes within taxa, adding complexity to chemophenetic exploration. The current study chemically characterised essential oils from 64 highly aromatic specimens, representative of 25 taxa, giving yields as high as >2% g/g. The chemical profiles of essential oils are diverse, but generally include 1,8-cineole and signatory compounds such as sesquiterpene oxides, caryophyllene oxide, kessane and cis-dihydroagarofuran; sesquiterpene alcohols, globulol, epiglobulol, maaliol, prostantherol, spathulenol and ledol; and monoterpene derivatives of common scaffolds, borneol, bornyl acetate, bornanone, linalool and linalyl acetate. As in previous studies, analysis of chemical data confirms that the chemistry strongly agrees with taxonomic classifications. Importantly, as in classical taxonomy, the current chemical study complemented morphological analysis but conveys chemovariation, obscuring the taxonomic agreement. Nevertheless, variation within taxa may be due to environmental factors, meaning that cultivation of species in gardens will create different chemical profiles as compared to those published here.
唇萼薄荷属的澳大利亚高芳香薄荷灌木丛经水蒸馏可高产精油。连同其丰富的历史、园艺潜力、标志性花朵和芳香叶片，它具有很高的观赏和烹饪价值。该属的物种表达高度多样且化学性质独特的精油，这些精油展示了种内和种间模式，一百多年来一直启发着分类学的重新诠释。先前的研究表明，挥发物的表型可塑性在分类群中产生化学型，增加了化学分类学探索的复杂性。本研究对代表25个分类群的64个高芳香标本的精油进行了化学表征，产率高达>2% g/g。精油的化学图谱各不相同，但通常包括1,8-桉叶素和标志性化合物，如倍半萜氧化物、石竹烯氧化物、克萨烷和顺式二氢agarofuran；倍半萜醇、球松醇、表球松醇、马阿里醇、香荆芥醇、匙叶桉油烯醇和ledol；以及常见骨架的单萜衍生物、冰片、乙酸冰片酯、龙脑酮、芳樟醇和乙酸芳樟酯。与先前的研究一样，化学数据分析证实化学性质与分类学分类高度一致。重要的是，与经典分类学一样，当前的化学研究补充了形态学分析，但传达了化学变异，模糊了分类学一致性。然而，分类群内的变异可能是由于环境因素，这意味着与这里发表的相比，在花园中种植物种将产生不同的化学图谱。
