Schimp., spreading earthmoss; Picea abies (L.) H. Karst; Norway spruce; Picea
Schimp., spreading earthmoss; Picea abies (L.) H. Karst; Norway spruce; Picea glauca (Moench) Voss; white spruce; Picea sitchensis (Bongard) Carri e; 1855; Sitka spruce; Pinus banksiana Lamb., jack pine; Pinus contorta Douglas; lodgepole pine; Pinus nigra J.F. Arnold; Austrian pine or black pine; Pinus nigra subsp. laricio (Poiret) Maire; Calabrian pine; Pinus pinaster Aiton; maritime pine; Pinus radiata D. Don; Monterey pine; Pinus taeda L., Hedgehog site loblolly pine; Pseudolarix amabilis (N. Nelson) Rehder; golden larch.Plants 2021, 10, 2391. doi/10.3390/plantsmdpi.com/journal/plantsPlants 2021, 10,two of1. Introduction Gymnosperms developed a range of physical and chemical defences against pathogens and herbivores, among which a single of the most considerable could be the production of terpenoid metabolites [1]. The complicated terpenoid defence mechanisms have persisted throughout the extended evolutionary history of gymnosperms and their decreasing geographical distribution during the Cenozoic era [5,6], but diversified into generally species-specific P2Y Receptor Antagonist list metabolite blends. For instance, structurally related labdane-type diterpenoids, such as ferruginol and derivative compounds, act as defence metabolites in numerous Cupressaceae species [3,7,8]. However, diterpene resin acids (DRAs), collectively with mono- and sesqui-terpenes, are the main components with the oleoresin defence program in the Pinaceae species (e.g., conifers), and have been shown to supply an efficient barrier against stem-boring weevils and related pathogenic fungi [92]. diterpenoids from gymnosperms are also crucial for their technological uses, getting employed inside the production of solvents, flavours, fragrances, pharmaceuticals and also a substantial collection of bioproducts [1,13], for example, amongst the lots of other examples, the anticancer drugs pseudolaric acid B, obtained from the roots with the golden larch (Pseudolarix amabilis) [14], and taxol, extracted from yew (Taxus spp.) [15], too as cis-abienol, developed by balsam fir (Abies balsamea), which can be a molecule of interest for the fragrance sector [16]. The diterpenoids of conifer oleoresin are largely members of 3 structural groups: the abietanes, the pimaranes, and the dehydroabietanes, all of that are characterized by tricyclic parent skeletons [2,17]. These diterpenoids are structurally comparable to the tetracyclic ent-kaurane diterpenes, which involve the ubiquitous gibberellin (GA) phytohormones. Each the oleoresin diterpenoids of specialized metabolism and the GAs of basic metabolism derive in the common non-cyclic diterpenoid precursor geranylgeranyl diphosphate (GGPP). In conifers, among the other gymnosperms, the structural diversity of diterpenoids benefits in the combined actions of diterpene synthases (DTPSs) and cytochrome P450 monooxygenases (CP450s) [2]. The former enzymes catalyse the cyclization and rearrangement on the precursor molecule GGPP into a selection of diterpene olefins, often referred to as the neutral elements of the oleoresins. Olefins are then functionalized at certain positions by the action of CP450s, through a sequential three-step oxidation very first for the corresponding alcohols, then to aldehydes, and finally to DRAs [2], which include abietic, dehydroabietic, isopimaric, levopimaric, neoabietic, palustric, pimaric, and sandaracopimaric acids, that are the big constituents of conifer oleoresins [2,17,18]. The chemical structures of the most-represented diterpenoids in Pinus spp. are reported in Figure S1. Dite.
