Biomedical subjects

Jean-Marie Bessière

Publications and source records attributed to Jean-Marie Bessière.

4 recordsLinked to original sources

PubMed2003

Composition and antimicrobial activity of the essential oil of Artemisia absinthium from Croatia and France.

The essential oils obtained by steam distillation from the aerial parts of two populations of Artemisia absinthium, from France and from Croatia, were analyzed by GC and GC-MS. The oils of A. absinthium of French origin contain (Z)-epoxyocimene and chrysanthenyl acetate as major components while the oils of Croatian A. absinthium contain mainly (Z)-epoxyocimene and beta-thujone. Analysis of oils before and after anthesis showed some quantitative differences. Analysis of separated leaves and flowering heads showed only few differences among these organs. As they contain no thujone, antimicrobial screening was performed on samples of French origin and showed that A. absinthium oil inhibited the growth of both tested yeasts (Candida albicans and Saccharomyces cerevisiae var. chevalieri).

Antifungal Agents↗

PubMed2002

Fig volatile compounds--a first comparative study.

We analysed the compounds of volatile blends released by receptive figs of twenty Ficus species to attract their specific pollinating wasps. In all, 99 different compounds were identified. The compounds are mainly terpenoids, aliphatic compounds and products from the shikimic acid pathway. In each species blend, there are few major compounds, which are generally common among floral fragrances. Most species blends also include rare compounds, but generally their proportion in the blend is low. A possible basis for species-specificity of Ficus-wasp interactions is discussed in relation to the patterns of volatiles found in this interspecies comparison.

Animals↗

PubMed2002

Composition of the essential oils of Hypericum perforatum L. from southeastern France.

The composition of the volatile oils from the aerial parts of Hypericum perforatum L. collected in six localities from southeastern France was analysed by GC-MS. Twenty-nine to 41 compounds have been identified in these volatile oils. The main constituents were sesquiterpene hydrocarbons, and minor variations were pointed out in the oil composition among the six populations. However, the composition of all the analysed oils greatly varied from that of the previous studies, carried out on H. perforatum essential oils from other localities, in which monoterpenoids were the major constituents, particularly, the alpha-pinene.

France↗

PubMed2002

Specific attraction of fig-pollinating wasps: role of volatile compounds released by tropical figs.

Floral scents often act as pollinator attractants. In the case of obligate and specific plant-pollinator relationships, the role of floral signals may be crucial in allowing the encounter of the partners. About 750 Ficus species (Moraceae) are involved in such interactions, each with a distinct species of pollinating wasp (Chalcidoidea, Agaonidae). Several species have been shown to release volatile compounds, but their role in pollinator attraction has rarely been simultaneously tested. We investigated the floral scents of four tropical fig species and combined chemical analysis with biological tests of stimulation of insects. Pollinators of three species were stimulated by the odor of their associated fig species and generally not by the odor of another species. The fourth actually comprised two distinct varieties. The main compound was often a different one in each species. Floral blends of different species always shared compounds, but ratios of these compounds varied among species.

Animals↗