Diterpenes from Euphorbia myrsinites and Their Anti-inflammatory Property

Euphorbia myrsinites is one of the oldest spurges described and used in folk medicine. It is characterized by blue-grey stems similar to myrtle, and it is spread in the Mediterranean region, Asia, and the USA. Chemical analysis of E. myrsinites collected in Turkey afforded the isolation of 4 diterpenes based on the so-called myrsinane skeleton being tetraesters of the tetracyclic diterpene alcohol myrsinol. In this study, the phytochemical analysis of this species collected in Italy has been undertaken to afford the isolation of a new atisane diterpene, named myrsatisane, 3 ingenol derivatives, along with the 4 tetraester derivatives previously found. A triterpene compound based on the euphane skeleton has also been isolated. Structural elucidation of the new myrsatisane was based on spectroscopic techniques, including HR-MS and 1- and 2-dimensional NMR experiments. Its relative configuration was determined by NOE correlations, while absolute stereochemistry was obtained by quantum-mechanical DFT studies. While diterpenes with the atisane skeleton are relatively common in Euphorbia species, this is the first report of an atisane diterpene from E. myrsinites. All the isolated terpenes were tested for anti-inflammatory activity on J774A.1 macrophages stimulated with lipopolysaccharide by evaluation of nitrite and pro-inflammatory cytokine Il-1β levels. Among tested compounds, the 3 ingenol diterpenes exhibited a dose-dependent (0.001 – 3 µM) significant activity, thus showing their potential as anti-inflammatory drug candidates.

Terpenoids in the Essential Oil and Concentrated Aromatic Products Obtained from Nicotiana glutinosa L. Leaves

N. glutinosa L. is a relatively less studied Nicotiana species (Solanaceae), although there are data about its importance as a model plant in viral control studies, as a gene donor in tobacco hybridization and as a source of agents with insecticidal or fungicidal effects. The biological activities of the species were associated mostly with the presence of leaf surface metabolites, in particular diterpenes and sucrose esters. The aim of this study was to identify the chemical composition of the essential oil (EO) and two aromatic extraction products (concrete and resinoid) obtained from N. glutinosa L. leaves. GC-MS analysis identified 26 components in the EO (representing 97.3% of total oil content), which contained mostly diterpene compounds with major components manool (14.2%), sclarene (8.4%) and manoyl oxide (8.1%). The number of compounds identified in the concrete was 37 (95.5% of the total content) and the major component was the diterpene alcohol sclareol (14.2%). In the resinoid, 30 volatile components (representing 95.1% of resinoid content) were identified, with major components nicotine (32.9%), α-tocopherol (8.2%), tridecanoin (6.9%), sclareol (6.9%), and solanone (6.9%). The group of bicyclic diterpenes had the largest share in the diterpene fraction of the products (57.3%, 91.7%, and 86.3%, respectively for the EO, concrete, and resinoid). Considering the abundance of sclareol in the aromatic products, the antimicrobial activity of the pure substance was determined. Sclareol was highly effective against a set of medicinally important yeasts; Candida albicans АТСС 10231, C. glabrata ATCC 90030, C. parapsilosis clinical isolate, and C. tropicalis NBIMCC 23, while being less effective against the studied Gram-positive and Gram-negative bacteria. Data from the study on N. glutinosa aromatic products composition may be of interest to the aroma industries for their possible use in perfumery and cosmetics.

18-Hydroxydolabella-3,7-diene synthase – a diterpene synthase from Chitinophaga pinensis

The product obtained in vitro from a diterpene synthase encoded in the genome of the bacterium Chitinophaga pinensis, an enzyme previously reported to have germacrene A synthase activity during heterologous expression in Escherichia coli, was identified by extensive NMR-spectroscopic methods as 18-hydroxydolabella-3,7-diene. The absolute configuration of this diterpene alcohol and the stereochemical course of the terpene synthase reaction were addressed by isotopic labelling experiments. Heterologous expression of the diterpene synthase in Nicotiana benthamiana resulted in the production of 18-hydroxydolabella-3,7-diene also in planta, while the results from the heterologous expression in E. coli were shown to be reproducible, revealing that the expression of one and the same terpene synthase in different heterologous hosts may yield different terpene products.

Isolation and Characterization of Phytol from Justicia gendarussa Burm. f.-An Anti-Inflammatory Compound

Justicia gendarussa burm.f. has become important source of Phytol which is associated with other phenolic,terpenoids,alkaloids. Diterpenes shows anti-inflammatory activity. Phytol is a acyclic diterpene alcohol found as essential oil in aromatic plants.oil is obtained by Keshav-Naren apparatus (patent no:2343/Mum/2013/A).Phytol separated from other oil part by fractional distillation. It separated at 204-2080C.Characterization of Phytol carried out by IR,NMR,and mass spectrometry. Phytol shows potent as Anti-inflammatory activity by releasing histamine (26.92%), serotin and bradykinin (49.90%), and prostaglandin (68.03%) as compared to standard (Dicolfenac 5mg/kg).

Presence of Phytol, a Precursor of Vitamin E in Chaetomorpha Antinnina

Phytol, a precursor of vitamin E was identified from green algae Chaetomorpha antinnina collected from Chullickal, Kochi Kerala coast, using GC-MS. Phytol is an acyclic diterpene alcohol that can be used as a precursor for the manufacture of synthetic forms of vitamin E and vitamin K1. The compound 3,7,11,15-tetramethylhexadec-2-en-1-ol also known as phytol which exist naturally only in single isomeric form having molecular formula C20H40O and molecular mass 296. From the total ion chromatogram more than twenty peaks were observed, the mass spectrum of the peak at Rt 21.53 was resolved and the major fragmentations were noted. Major fragmentation were m/z 71 the base peak, m/z 296 the molecular ion peak, m/z 43, m/z 57, m/z 81, m/z 95, and m/z 123. It was found that there are some other compounds apart from this identified phytol which are more complicated in structure and cannot be characterised using GC-MS. Phytol is reported to have both antimicrobial and anticancer activities. The green algae Chaetomorpha antinnina can be proposed to be a good natural source for production of phytol.

Combined Analysis by GC (RI), GC-MS and 13C NMR of the Supercritical Fluid Extract of Abies alba Twigs

Two samples (leaves and twigs) of Abies alba Miller from Corsica were extracted using supercritical CO2 and their chemical compositions were compared with those of the essential oils obtained from the same batch of plant material. In total 45 components were identified using combined analysis by GC (RI), GC-MS and 13C NMR. It was observed that the contents of monoterpenes (mainly represented by limonene, α-pinene and camphene) were significantly lower in the supercritical fluid extract (SFE) than in the essential oil (EO). Conversely, the proportions of sesquiterpenes were much higher in CO2 extracts than in essential oils (around 30% vs 4%). Cis-abienol, a diterpene alcohol, was identified only in SFE, and the proportions of this constituent (7.5% and 17.3%) were determined using quantitative 13C NMR since it was under estimated using the standard conditions of GC.