Phila Raharivelomanana

Eudesmane sesquiterpenes from laggera alata

Two new eudesmane-type sesquiterpenoids (7-epi-γ-eudesmol and 7-epi-β-eudesmol) were isolated and characterized along with five other sesquiterpene compounds (β-selinene, 7-epi-α-eudesmol, isointermedeol, juniper camphor and β-dihydroagarofuran) from the essential oil of Laggera alata var. alata grown in Madagascar. The assigned structures were based on their spectral data.

Screening of anti-HIV-1 inophyllums by HPLC–DAD of Calophyllum inophyllum leaf extracts from French Polynesia Islands

Various pyranocoumarins, calophyllolide, inophyllums B, C, G(1), G(2) and P, from Calophyllum inophyllum (Clusiaceae) leaves of French Polynesia (Austral, Marquesas, Society and Tuamotu archipelagos) have been determined in 136 leaf extracts using a high pressure liquid chromatography-UV-diode array detection (HPLC-UV-DAD) technique. Results show a wide range in chemical composition within trees growing on eighteen islands. The use of multivariate statistical analyses (PCA) shows geographical distribution of inophyllums and indicate those rich in HIV-1 active (+)-inophyllums. Inophyllum B and P contents (0.0-39.0 and 0.0-21.8 mg kg(-1), respectively) confirm the chemodiversity of this species within the large area of French Polynesia. The study suggests the presence of interesting chemotypes which could be used as plant source for anti-HIV-1 drugs.

Nukuhivensiums, indolo[2,3-a]quinoliziniums from the Marquesan plant Rauvolfia nukuhivensis.

The first phytochemical inspection of the Marquesan endemic plant Rauvolfia nukuhivensis led to the isolation and structure characterization of two new indolo[2,3‑a]quinolizinium derivatives named nukuhivensium (1) and N12-methyl-nukuhivensium (2). They feature an aromatic indolo[2,3-a]quinolizinium core, substituted at C-2 by a n-propyl group, which is unusual in this family of alkaloid derivatives. The structure elucidation was performed on the basis of NMR spectroscopy and especially by interpretation of 2D HMBC correlations. A biosynthetic pathway is proposed on the basis of known enzymatic transformations for this family of natural products. These compounds exhibited low antimicrobial activities.

Indole alkaloids from the Marquesan plant Rauvolfia nukuhivensis and their effects on ion channels

In addition to the already reported nukuhivensiums 1 and 2, 11 indole alkaloids were isolated from the bark of the plant Rauvolfia nukuhivensis, growing in the Marquesas archipelago. The known sandwicine (3), isosandwicine (4), spegatrine (8), lochneram (9), flavopereirine (13) have been found in this plant together with the norsandwicine (5), isonorsandwicine (6), Nb-methylisosandwicine (7), 10-methoxypanarine (10), nortueiaoine (11), tueiaoine (12). The structure elucidation was performed on the basis of a deep exploration of the NMR and HRESIMS data as well as comparison with literature data for similar compounds. Norsandwicine, 10-methoxypanarine, tueiaoine, and more importantly nukuhivensiums, were shown to significantly induce a reduction of IKr amplitude (HERG current). Molecular modelling through docking was performed in order to illustrate this result.

Bisabolane sesquiterpenoids from Santalum austrocaledonicum

Abstract Two new sesquiterpenoids, 6,13-dihydroxybisabola-2,10-diene and 7,13-dihydroxybisabola-2,10-diene, were isolated, together with ( E )-anceol, from the heartwood of Santalum austrocaledonicum var. austrocaledonicum . The compounds were characterized by one- and two-dimensional NMR.

Two guaiane and eudesmane-type sesquiterpenoids from Neocallitropsis pancheri

Two new sesquiterpenoids with the guaiane and eudesmane carbon skeleton termed pancherione and eudesm-4(14)-en-3α, 11-diol, were isolated from the heartwood of Neocallitropsis pancheri and characterized by 1D and 2D NMR spectroscopy. Trans-dihydrocarissone and α-, β- and γ-costols were also obtained from this plant for the first time and their NMR parameters are given.

α-Santaldiol and β-santaldiol, two santalane sesquiterpenes from Santalum insulare

Two new sesquiterpene alcohols, β-santaldiol and α-santaldiol, have been isolated from the heartwood of Santalum insulare var. marchionense and, by means of two-dimensional NMR experiments, shown to have the β- and α-santalane skeleton, respectively.

Structure de deux nouvelles iminomycosporines isolées de Pocillopora eydouxi

Abstract Deux nouvelles molecules UV absorbantes de la famille des iminomycosporines a residu acides amines ont ete isolees et caracterisees a partir du corail recifal Pocillopora eydouxi : la palythine-serine ( 1 ) ( λ max = 320 nm) et la N-methylmycosporine-serine ( 2 ) ( λ max = 325 nm).

Volatile Constituents of Neocallitropsis pancheri (Carrière) de Laubenfels Heartwood Extracts (Cupressaceae)

ABSTRACT The chemical composition of the heartwood oil of Neocallitropsis pancheri (Cupressaceae) obtained by steam distillation, has been established using GC/MS, GC/FTIR, Kovats indices and NMR data. The major components were found to be α-eudesmol (13.26%), β-eudesmol (25.92%), γ-eudesmol (19.04%), guaiol (3.02%) elemol (4.99%), β-bisabolenol (4.93%) and bulnesol (3.69%). Almost 40 compounds have been identified, 32 of which, including three new sesquiterpenoids (β-bisabolenal, β-bisabolenol and β-acoradienol), are reported for the first time in this oil. Isolation of a concentrate of the volatiles from N. pancheri using different solvents, and steam distillation produced concentrates of different yields (6.96–12.9%) and chemical composition. Some components were found to be subject to quantitative variation in the different wood concretes.

The Wound Healing and Antibacterial Activity of Five Ethnomedical Calophyllum inophyllum Oils: An Alternative Therapeutic Strategy to Treat Infected Wounds.

Background Calophyllum inophyllum L. (Calophyllaceae) is an evergreen tree ethno-medically used along the seashores and islands of the Indian and Pacific Oceans, especially in Polynesia. Oil extracted from the seeds is traditionally used topically to treat a wide range of skin injuries from burn, scar and infected wounds to skin diseases such as dermatosis, urticaria and eczema. However, very few scientific studies reported and quantified the therapeutic properties of Calophyllum inophyllum oil (CIO). In this work, five CIO from Indonesia (CIO1), Tahiti (CIO2, 3), Fiji islands (CIO4) and New Caledonia (CIO5) were studied and their cytotoxic, wound healing, and antibacterial properties were presented in order to provide a scientific support to their traditional use and verify their safety. Methods The safety of the five CIO was ascertained using the Alamar blue assay on human keratinocyte cells. CIO wound healing properties were determined using the scratch test assay on human keratinocyte cells. CIO-stimulated antibacterial innate immune response was evaluated using ELISA by measuring β defensin-2 release in human derivative macrophage cells. CIO antibacterial activity was tested using oilogramme against twenty aerobic Gram- bacteria species, twenty aerobic Gram+ bacteria species, including a multi-drug resistant Staphylococcus aureus strain and two anaerobic Gram+ bacteria species e.g. Propionibacterium acnes and Propionibacterium granulosum. To detect polarity profile of the components responsible of the antibacterial activity, we performed bioautography against a Staphylococcus aureus strain. Results Based on Alamar Blue assay, we showed that CIO can be safely used on keratinocyte cells between 2.7% and 11.2% depending on CIO origin. Concerning the healing activity, all the CIO tested accelerated in vitro wound closure, the healing factor being 1.3 to 2.1 higher compared to control when keratinocytes were incubated after scratch with CIO at 0.1%. Furthermore, our results showed that CIO exhibit two distinct antibacterial effects: one against Gram+ bacteria by direct inhibition of mitotic growth and another potent effect against Gram- bacteria due to increased release of β-defensin 2 peptide by macrophages. Interestingly, the needed concentrations of CIO to inhibit bacteria growth and to promote wound healing are lower than concentrations exhibiting cytotoxic effects on keratinocyte cells. Finally, we performed bioautography assay against Staphylococcus aureus to determine polarity profile of the components responsible for CIO antibacterial activity. Our results showed for the five tested CIO that components responsible of the bacterial growth inhibition are the more polar one on the TLC chromatographic profile and are contained in the resinous fraction of the oil. Conclusions This study was conducted to evaluate cytotoxicity, wound healing and antibacterial properties of five CIO traditionally used to treat infected wounds. Using cell and bacteria cultures, we confirmed the pharmacological effects of CIO as wound healing and antimicrobial agent. Moreover, we showed that concentration of CIO needed to exhibit therapeutic effects are lower than concentrations exhibiting cytotoxic effects in vitro. For the first time, this study provides support for traditional uses of CIO. These wound healing and antibiotic properties make CIO a valuable candidate to treat infected wounds especially in tropical areas.