Functional characterization of the cytochrome P450 monooxygenase CYP71AU87 indicates a role in marrubiin biosynthesis in the medicinal plant Marrubium vulgare.

BackgroundHorehound (Marrubium vulgare) is a medicinal plant whose signature bioactive compounds, marrubiin and related furanoid diterpenoid lactones, have potential applications for the treatment of cardiovascular diseases and type II diabetes. Lack of scalable plant cultivation and the complex metabolite profile of M. vulgare limit access to marrubiin via extraction from plant biomass. Knowledge of the marrubiin-biosynthetic enzymes can enable the development of metabolic engineering platforms for marrubiin production. We previously identified two diterpene synthases, MvCPS1 and MvELS, that act sequentially to form 9,13-epoxy-labd-14-ene. Conversion of 9,13-epoxy-labd-14-ene by cytochrome P450 monooxygenase (P450) enzymes can be hypothesized to facilitate key functional modification reactions in the formation of marrubiin and related compounds.ResultsMining a M. vulgare leaf transcriptome database identified 95 full-length P450 candidates. Cloning and functional analysis of select P450 candidates showing high transcript abundance revealed a member of the CYP71 family, CYP71AU87, that catalyzed the hydroxylation of 9,13-epoxy-labd-14-ene to yield two isomeric products, 9,13-epoxy labd-14-ene-18-ol and 9,13-epoxy labd-14-ene-19-ol, as verified by GC-MS and NMR analysis. Additional transient Nicotiana benthamiana co-expression assays of CYP71AU87 with different diterpene synthase pairs suggested that CYP71AU87 is specific to the sequential MvCPS1 and MvELS product 9,13-epoxy-labd-14-ene. Although the P450 products were not detectable in planta, high levels of CYP71AU87 gene expression in marrubiin-accumulating tissues supported a role in the formation of marrubiin and related diterpenoids in M. vulgare.ConclusionsIn a sequential reaction with the diterpene synthase pair MvCPS1 and MvELS, CYP71AU87 forms the isomeric products 9,13-epoxy labd-14-ene-18/19-ol as probable intermediates in marrubiin biosynthesis. Although its metabolic relevance in planta will necessitate further genetic studies, identification of the CYP71AU87 catalytic activity expands our knowledge of the functional landscape of plant P450 enzymes involved in specialized diterpenoid metabolism and can provide a resource for the formulation of marrubiin and related bioactive natural products

Cassane diterpenoids from lonchocarpus laxiflorus

This article examines cassane diterpenoids from lonchocarpus laxiflorus

Indole diterpenoid natural products as the inspiration for new synthetic methods and strategies.

Indole terpenoids comprise a large class of natural products with diverse structural topologies and a broad range of biological activities. Accordingly, indole terpenoids have and continue to serve as attractive targets for chemical synthesis. Many synthetic efforts over the past few years have focused on a subclass of this family, the indole diterpenoids. This minireview showcases the role indole diterpenoids have played in inspiring the recent development of clever synthetic strategies, and new chemical reactions

Enantioselective Total Synthesis of Macfarlandin C, a Spongian Diterpenoid Harboring a Concave-Substituted cis-Dioxabicyclo[3.3.0]octanone Fragment.

The enantioselective total synthesis of the rearranged spongian diterpenoid (-)-macfarlandin C is reported. This is the first synthesis of a rearranged spongian diterpenoid in which the bulky hydrocarbon fragment is joined via a quaternary carbon to the highly hindered concave face of the cis-2,8-dioxabicyclo[3.3.0]octan-3-one moiety. The strategy involves a late-stage fragment coupling between a tertiary carbon radical and an electrophilic butenolide resulting in the stereoselective formation of vicinal quaternary and tertiary stereocenters. A stereoselective Mukaiyama hydration that orients a pendant carboxymethyl side chain cis to the bulky octahydronapthalene substituent was pivotal in fashioning the challenging concave-substituted cis-dioxabicyclo[3.3.0]octanone fragment

Why do Euphorbiaceae tick as medicinal plants? : a review of Euphorbiaceae family and its medicinal features

Euphorbiaceae is among the large flowering plant families consisting of a wide variety of vegetative forms some of which are plants of great importance. Its classification and chemistry have of late been subjects of interest possibly because of the wide variety of chemical composition of its members, many of which are poisonous but useful. In this review, we have tried to demonstrate why Euphorbiaceae are important medicinal plants. Two important issues have come up. The worldwide distribution of the family exposes its members, to all sorts of habitats to which they must adapt, therefore inducing a large variety of chemicals (secondary substances) that are employed for survival/defense. Succulence and the CAM (crassulacean acid metabolism) pathway that characterize a good number of its members were quoted as some of the adaptations that aid colonization and survival to achieve this induction. We have also found out that medicinal properties of some of its species may be due to stress factors that characterize most habitats of the family. Varying stress factors like temperature, salinity, drought and others were seen to operate in tandem with genetic factors such as gene expression and mutation loads to bring about synthesis of a wide assemblage of secondary substances that may probably be responsible for the family's medicinal nature. It was concluded that the family is a good starting point for the search for plant-based medicines

Euphorbia-derived natural products with potential for use in health maintenance

Euphorbia genus (Euphorbiaceae family), which is the third largest genus of angiosperm plants comprising ca. 2000 recognized species, is used all over the world in traditional medicine, especially in the traditional Chinese medicine. Members of this taxa are promptly recognizable by their specialized inflorescences and latex. In this review, an overview of Euphorbia-derived natural products such as essential oils, extracts, and pure compounds, active in a broad range of biological activities, and with potential usages in health maintenance, is described. The chemical composition of essential oils from Euphorbia species revealed the presence of more than 80 phytochemicals, mainly oxygenated sesquiterpenes and sesquiterpenes hydrocarbons, while Euphorbia extracts contain secondary metabolites such as sesquiterpenes, diterpenes, sterols, flavonoids, and other polyphenols. The extracts and secondary metabolites from Euphorbia plants may act as active principles of medicines for the treatment of many human ailments, mainly inflammation, cancer, and microbial infections. Besides, Euphorbia-derived products have great potential as a source of bioactive extracts and pure compounds, which can be used to promote longevity with more health.Agência financiadora FCT/MCT, supporting the cE3c centre UID/BIA/00329/2013 UID/BIA/00329/2019 QOPNA research Unit (FCT) UID/QUI/00062/2019info:eu-repo/semantics/publishedVersio

Chemical composition, antibacterial and repellent activities of Azorella trifurcata, Senecio pogonias, and Senecio oreophyton essential oils

The antibacterial and insect-repellent activities of the essential oils (EOs) from Argentinian medicinal plants Azorella trifurcata (Gaertn.) Pers., Senecio cfr. oreophyton J. Remy and Senecio cfr. pogonias Cabrera, were investigated. All EOs showed good repellent properties against Triatoma infestans Klug, the vector of the Chagas disease, with percent repellence values between 60% and 70% at 24 hours compared with positive control N-N diethyl-m-methylbenzamide (DEET) and moderate activity against the bacteria tested with minimum inhibitory concentrations (MICs) values between 31.2 and 2000 μg/ml. The Azorella trifurcata, Senecio pogonias and S. oreophyton EOs, obtained by hydrodistillation, were characterized by GC-FID and GC/MS analyses. Spathulenol (38.2%), myrtenyl acetate (8.4%) and α-terpineol (4.5%), limonene (9.8%) and α-thujene (5.4%) were the main constituents in the EO of Azorella trifurcata. The Senecio pogonias and S. oreophyton EOs are characterized by a high content of monoterpenes hydrocarbons (92% and 95.1%, respectively) with α-pinene, the main component in both oils. To our knowledge, the essential oil composition from Andean medicinal plants A. trifurcata, Senecio pogonias and S. oreophyton collected in central Andean slopes are reported for first time.Fil: López, Sandra Beatriz. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Biotecnología; ArgentinaFil: Lima, Beatriz Viviana. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Agüero, María Belén. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: López, María Liza. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Hadad, Martín Ariel. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Zygadlo, Julio Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Caballero, Duilio. Provincia de San Juan. Hospital Marcial Quiroga; ArgentinaFil: Stariolo, Raúl Luis. Ministerio de Salud. Secretaría de Programas Sanitarios. Subsecretaría de Programas de Prevención y Promoción. Coordinación Nacional de Control de Vectores; ArgentinaFil: Suero, Eduardo. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Biotecnología; ArgentinaFil: Feresin, Gabriela Egly. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Tapia, Alejandro. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Biotecnología; Argentin