'Biomarqueurs et Bioindicateurs Environnementaux', Institut Méditerranéen d'Ecologie et de Paléoécologie UMR-CNRS 6116, Case 97 Université de Provence 3, place Victor Hugo 13331 Marseille Cedex 3, France
• 1977 Assistant du centre associé au CNAM de ROUEN 3 mois • 1977-1979 Boursier DGRST à l ’ EA203 de l’Université de ROUEN • 1979-1981 Maître Assistant en Physiologie et Biochimie Végétale Université d’Es-Senia, Oran (Algérie) Dépt Botanique dans le cadre d ’accords interuniversitaires • 1981-1982 Stage de 1 mois à l’Institut Botanique de l ’Université de Munich, puis ingénieur de recherche en CDD à l’Université Technologique de Compiègne. • 1 Janvier 1983 Assistant à l’Université de Provence et Création du Laboratoire de Physiologie Cellulaire Végétale en septembre • 1 Septembre 1989 MCF 2°classe à l’Université de Provence • 1999 Association à l’équipe DYREVE en création, 1 Septembre MCF 1°classe à l’Université de Provence • 1 Mars-30 Août 2000 Congé pour recherche et/ou reconversion thématique-contingent CNU, session 1999. au « Colorado State University » et au « James Madison University » USA • 2004 MCF Restructuration des équipes et agrément de l’Equipe Biodiversité et Environnement. • 17 Novembre 2004 HDR à l’Université Technologique de Compiègne. • Janvier 2008 intégration à l’IMEP (Université de Provence)
Abstract: Grevillea exul var. exul, an endemic serpentinic Proteaceae of New Caledonia, was chosen to study the spatial distribution of Ni because this species supports strong content of metals, which can allow important absorptions thus detectable by microanalysis. Fine transversal sections of axenic G. exul var. exul plants grown during 15 days on nickel sulphate medium were examined by EDXS microanalysis. It showed that in Ni treated plants, Ni was concentrated mostly in the phloem compared to the xylem and the epidermis, either in roots or in the basal part of the stems and was mostly in the epidermis in the upper part of the stems and not detectable in the leaves. This metal took the place of P and K in the treated plants whereas the localization of these macroelements was quite uniform in control sections. We assume that a mechanism of phloem loading is implicated to restrict Ni accumulation in G. exul var. exul.
Abstract: Grevillea exul var exul (Proteaceae), a tree species native to serpentine soils in New Caledonia, is a reported manganese accumulator. Since the metal tolerance of this species remains unknown, its growth and metal accumulation were studied for seven heavy metals under controlled conditions. Brassica juncea, a popular species for metal phytoremediation, was used as a reference. G. exul seedlings were more tolerant to Cr, Zn, Ni, and Cu than B. juncea. There were no differences in Hg, and Cd tolerance between both species. B. juncea seedlings concentrated more Cd, Hg, and Cr in their shoot than G. exul seedlings, while Ni, Zn, and Mn levels were similar for both species. Comparison then focused on tolerance at toxic doses of Ni and Mn using older individuals of both species. No growth inhibition for G. exul plants was observed, whereas the growth of B. juncea was significantly inhibited at the higher metal concentrations. Shoot Mn and Ni concentrations were again lower in G. exul plants as compared to B. juncea, suggesting a mechanism of partial Ni and Mn exclusion in G. exul. In a subsequent study, 1-year-old G. exul plants favored Ni accumulation in roots while Mn accumulated preferentially in shoots.
Abstract: The aim of this study was to precise anatomical and morphological features of the species Styrax officinalis with the help of current microscopic techniques, those features being of interest as valuable taxonomic characters. Typical hairy structures were observed on all surfaces of the aerial organs and their location, density and size were specified. Moreover, we demonstrated the occurrence of secretory glands in the leaf blades. These structures were revealed for the first time for this species.
Abstract: Numerous original alkaloids are present in tubers of Arisarum vulgare Targ. a species belonging to the Araceae family known in Morocco for its toxicity. Some previous works deal with the activity of these natural compounds as R-irniine. As the enantioselective total synthesis of irniine has been realised, the R- and S-forms were obtained and this last one could be tested. Thus, a study of the cytotoxicity and the electrophysiological activity of S-irniine was carried out on human MRC-5 fibroblasts. A cytotoxic effect of S-irniine at 40 microg/mL was detected on MRC-5 fibroblasts. An electrophysiological study was also carried out on the MRC-5 cells by using the patch-clamp technique and no effect of this compound at this concentration on the outward potassium current of MRC-5 fibroblasts was observed. Thus, this study showed, as it was for R-irniine, that the cytotoxicity of S-irniine was not explained by an effect on the potassium currents.
Abstract: BACKGROUND AND AIMS: Serpentine soils are usually quite infertile, arid and toxic, mainly because they contain high levels of heavy metals such as Ni. The aim of the present work was to assess the effects of Ni on the germinating seeds of Grevillea exul var. rubiginosa, an endemic serpentine Proteaceae of New Caledonia. In addition, the distribution of macronutrients and the Ni levels in germinating seeds were examined. METHODS: Seeds were sown in glass Petri dishes and exposed to increasing concentrations of Ni (5 to 500 mg Ni L(-1)) using Ni chloride, Ni sulphate and Ni acetate. The germination percentage and root length were measured after 40 d. Longitudinal frozen sections of germinating seeds growing in the presence of Ni (500 mg L(-1) for all three salts) were used for X-ray microanalysis and X-ray elemental mapping using scanning electron microscopy (SEM). KEY RESULTS: Ni chloride resulted in the greatest reductions in germination and root growth, particularly at 500 mg L(-1), followed by Ni sulphate and Ni acetate. SEM images revealed Ca crystalline structures in the seed coat for all the samples. S/Ca and Mg/P/K/Mn were found to be distributed differently in Ni-treated samples, whereas they all followed the same pattern in the controls. For all three salts, the Ni added to the medium had accumulated in the seed coat, whereas the endosperm seemed to be devoid of Ni. CONCLUSIONS: It is assumed that the seed coat is able to reduce the amount of Ni entering the seed, and that a high level of Ni induced the mobilization of macronutrients.
Abstract: R-irniine is a natural 2-alkylpyrrolidine alkaloid extracted from Arisarum vulgare Targ., a species belonging to the Araceae family known in Morocco for its toxicity. Cytotoxic and electrophysiological studies of this compound on human MRC-5 fibroblasts were carried out. Cytotoxic potential of R-irniine was detected on MRC-5 fibroblasts at 40 microg/mL. We carried out the electrophysiological study of this compound on MRC-5 cells by using the technique of patch-clamp in "Whole cell" configuration. R-irniine showed no effect on the outward potassium current of the MRC-5 fibroblasts.
