Essential Oil of Otanthus maritimus (L.) Hoffmanns. & Link from Algeria with High Content in (α/β)-Isocomene and α-epi Bisabolol.

Essential oils (EO) are a potential source of biologically active molecules. Knowing exactly the constituents of an EO is fundamental to verify its quality and to predict its biological potential and toxicity. Thus, the objective of this work is to determine the chemical constituents and the chemotype of the EO of Otanthus maritimus (L.

Citronellol biosynthesis in pelargonium is a multistep pathway involving progesterone 5β-reductase and/or iridoid synthase-like enzymes.

Citronellol is a pleasant-smelling compound produced in rose (Rosa spp.) flowers and in the leaves of many aromatic plants, including pelargoniums (Pelargonium spp.).

Erratum: Despinasse et al. Structure of the Chemical and Genetic Diversity of the True Lavender over Its Natural Range. 2020, , 1640.

As requested by the Editorial Office, the authors remove the scientific consortium "Camille Nous" from the author list and the Author Contributions section in the published paper [...

Structure of the Chemical and Genetic Diversity of the True Lavender over Its Natural Range.

The true lavender Miller is a Mediterranean aromatic shrub widely cultivated for its high quality essential oil used in perfumery and phytotherapy. Despite its economic importance, the intra-specific diversity among wild, non-cultivated plants remains poorly understood. We analyzed the structure of the chemical and genetic diversity of plants from 14 sites sampled over the entire native range of the true lavender.

Phytochemical analysis, cytotoxic and antioxidant activities of Myrtus communis essential oil from Morocco.

Background Myrtus communis L. is an aromatic evergreen plant common in Morocco. In addition to its culinary uses, it has been used medicinally as a disinfectant, an antiseptic or as a hypoglycemic agent.

Functional Analysis of Four Terpene Synthases in Rose-Scented Pelargonium Cultivars ( × ) and Evolution of Scent in the Genus.

genus contains about 280 species among which at least 30 species are odorant. Aromas produced by scented species are remarkably diverse such as rose, mint, lemon, nutmeg, ginger and many others scents. Amongst odorant species, rose-scented pelargoniums, also named pelargonium rosat, are the most famous hybrids for their production of essential oil (EO), widely used by perfume and cosmetic industries.

Linalool and linalool nerolidol synthases in roses, several genes for little scent.

Roses are widely appreciated for the appearance of their flowers and for their fragrance. This latter character results from the combination of different odorant molecules among which monoterpenes are often prevalent constituents. In this study, we report the cloning and characterization of three rose monoterpene synthases.

Virus-induced gene silencing of the two squalene synthase isoforms of apple tree (Malus × domestica L.) negatively impacts phytosterol biosynthesis, plastid pigmentation and leaf growth.

The use of a VIGS approach to silence the newly characterized apple tree SQS isoforms points out the biological function of phytosterols in plastid pigmentation and leaf development. Triterpenoids are beneficial health compounds highly accumulated in apple; however, their metabolic regulation is poorly understood. Squalene synthase (SQS) is a key branch point enzyme involved in both phytosterol and triterpene biosynthesis.

Bornyl-diphosphate synthase from Lavandula angustifolia: A major monoterpene synthase involved in essential oil quality.

Lavender essential oils (EOs) of higher quality are produced by a few Lavandula angustifolia cultivars and mainly used in the perfume industry. Undesirable compounds such as camphor and borneol are also synthesized by lavender leading to a depreciated EO. Here, we report the cloning of bornyl diphosphate synthase of lavender (LaBPPS), an enzyme that catalyzes the production of bornyl diphosphate (BPP) and then by-products such as borneol or camphor, from an EST library.

PLANT VOLATILES. Biosynthesis of monoterpene scent compounds in roses.

The scent of roses (Rosa x hybrida) is composed of hundreds of volatile molecules. Monoterpenes represent up to 70% percent of the scent content in some cultivars, such as the Papa Meilland rose. Monoterpene biosynthesis in plants relies on plastid-localized terpene synthases.

Functional characterization of terpene synthases and chemotypic variation in three lavender species of section Stoechas.

Lavandula pedunculata (Mill.) Cav. subsp.

Isolation and functional characterization of a τ-cadinol synthase, a new sesquiterpene synthase from Lavandula angustifolia.

In this paper we characterize three sTPSs: a germacrene D (LaGERDS), a (E)-β-caryophyllene (LaCARS) and a τ-cadinol synthase (LaCADS). τ-cadinol synthase is reported here for the first time and its activity was studied in several biological models including transiently or stably transformed tobacco species. Three dimensional structure models of LaCADS and Ocimum basilicum γ-cadinene synthase were built by homology modeling using the template structure of Gossypium arboreum δ-cadinene synthase.

Extracellular localization of the diterpene sclareol in clary sage (Salvia sclarea L., Lamiaceae).

Sclareol is a high-value natural product obtained by solid/liquid extraction of clary sage (Salvia sclarea L.) inflorescences. Because processes of excretion and accumulation of this labdane diterpene are unknown, the aim of this work was to gain knowledge on its sites of accumulation in planta.

Essential oils from wild populations of Algerian Lavandula stoechas L.: composition, chemical variability, and in vitro biological properties.

In an effort to develop local productions of aromatic and medicinal plants, a comprehensive assessment of the composition and biological activities of the essential oils (EOs) extracted from the aerial flowering parts of wild growing Lavandula stoechas L. collected from eleven different locations in northern Algeria was performed. The oils were characterized by GC-FID and GC/MS analyses, and 121 compounds were identified, accounting for 69.

Lavender inflorescence: a model to study regulation of terpenes synthesis.

We analysed VOC composition of complete inflorescences and single flowers of lavender during the flowering period. Our analyses, focused on the 20 most abundant terpenes, showed that three groups of components could be separated according to their patterns of variation during inflorescence ontogeny. These three groups were associated with three developmental stages: flower in bud, flower in bloom and faded flower.

Differential accumulation of volatile terpene and terpene synthase mRNAs during lavender (Lavandula angustifolia and L. x intermedia) inflorescence development.

Despite the commercial importance of Lavandula angustifolia Mill. and L. x intermedia Emeric ex Loisel floral essential oils (EOs), no information is currently available on potential changes in individual volatile organic compound (VOC) content during inflorescence development.

One-step identification of conserved miRNAs, their targets, potential transcription factors and effector genes of complete secondary metabolism pathways after 454 pyrosequencing of calyx cDNAs from the Labiate Salvia sclarea L.

The outermost floral whorl, composed of sepals, is generally thought to function in the protection of reproductive tissues. In the plant family Lamiaceae, sepals are fused into a tube that is densely covered by hairs for mechanical defence and contains secondary metabolites for chemical defence against insects and abiotic stresses. Despite the importance of this tissue in plant fitness, virtually no study has addressed the basic aspects of sepal development and functioning.

Production and emission of volatile compounds by petal cells.

We localized the tissues and cells that contribute to scent biosynthesis in scented and non-scented Rosa x hybrida cultivars as part of a detailed cytological analysis of the rose petal. Adaxial petal epidermal cells have a typical conical, papillate shape whereas abaxial petal epidermal cells are flat. Using two different techniques, solid/liquid phase extraction and headspace collection of volatiles, we showed that, in roses, both epidermal layers are capable of producing and emitting scent volatiles, despite the different morphologies of the cells of these two tissues.

Both the adaxial and abaxial epidermal layers of the rose petal emit volatile scent compounds.

The localization and timing of production and emission of scent was studied in different Rosa x hybrida cultivars, focusing on three particular topics. First, it was found that petals represent the major source of scent in R. x hybrida.

Role of petal-specific orcinol O-methyltransferases in the evolution of rose scent.

Orcinol O-methyltransferase (OOMT) 1 and 2 catalyze the last two steps of the biosynthetic pathway leading to the phenolic methyl ether 3,5-dimethoxytoluene (DMT), the major scent compound of many rose (Rosa x hybrida) varieties. Modern roses are descended from both European and Chinese species, the latter being producers of phenolic methyl ethers but not the former. Here we investigated why phenolic methyl ether production occurs in some but not all rose varieties.

Biosynthesis of the major scent components 3,5-dimethoxytoluene and 1,3,5-trimethoxybenzene by novel rose O-methyltransferases.

In Chinese rose species and in many modern varieties, two methylated phenolic derivatives, 3,5-dimethoxytoluene and 1,3,5-trimethoxybenzene, are major scent components. We show that cell-free extracts of rose petals catalyse the synthesis of 3,5-dimethoxytoluene and 1,3,5-trimethoxybenzene by methylation of precursor molecules. An expressed sequence tag approach was used to identify four highly similar O-methyltransferase sequences expressed specifically in petals and anthers.