Biomedical subjects

André-Michel Loiseau

Publications and source records attributed to André-Michel Loiseau.

3 recordsLinked to original sources

PubMed2006

Comparison of the amounts of volatile compounds in French protected designation of origin virgin olive oils.

Headspace solid-phase microextraction (HS-SPME) -gas chromatography using flame ionization detection and multivariate analysis were applied to the study of the specificity of protected designation of origin (PDO) virgin olive oils produced in a southern French region (Alpes-Maritimes) based on their volatile compounds. A total of 35 PDO olive oils from Nice, 6 commercial oils, and 12 other French PDO olive oils were analyzed. Recorded data were subjected to principal component analysis (PCA) and soft independent modeling of class analogy (SIMCA). The method developed here was able to perfectly distinguish different qualities of olive oils. Representative samples from each class obtained by chemometric treatment were analyzed by HS-SPME and GC-MS. PCA and SIMCA of chromatographic data were related to sensory analysis and led to a better understanding of the chemical features and observed sensory effects of olive oils.

Chromatography, Gas↗

PubMed2006

Enantiomer separation of 1,4-sulfanylalcohols by conventional and low-temperature gas chromatography.

Since 1990, the family of organosulfur molecules has assumed increasing importance in pheromone, flavour, and fragrance chemistry. Depending on the constitution of the functional groups, various volatile sulfur-containing compounds are chiral. However, hitherto it has been impossible to study the chirality of 1,4-sulfanylalcohols, since no adequate enantioselective analytical technique has been available. Here we report on the enantiomer separation of ten volatile 1,4-sulfanylalcohol homologues by applying an heptakis(6-O-tert-butyldimethylsilyl-2,3-di-O-methyl)-beta-cyclodextrin phase, involving in some cases the use of a low-temperature gas chromatographic (ltGC) technique. The results are expected to open research potential on the asymmetry of volatile organosulfur molecules, particularly in the fields of pheromone, flavour, and fragrance research.

Alcohols↗

PubMed2003

Comparison of static headspace, headspace solid phase microextraction, headspace sorptive extraction, and direct thermal desorption techniques on chemical composition of French olive oils.

Static headspace (SHS), headspace solid phase microextraction (HS-SPME), headspace sorptive extraction (HSSE), and direct thermal desorption (DTD) were applied to the analysis of four French virgin olive oils from Corsica. More than 60 compounds were isolated and characterized by GC-RI and GC-MS. SHS was not suited to the characterization of olive oil volatile compounds because of low sensitivity. The SPME and HSSE techniques were successfully applied to olive oil headspace analysis. Both methods allow the characterization of volatile compounds (mainly C(6) aldehydes and alcohols), which contribute significantly to the "green" flavor note of virgin olive oils. The PDMS stir bar showed a higher concentration capacity than a DVB/CAR/PDMS SPME fiber due to the higher volume of polymeric coating. DTD was a very good tool for extracting volatile and especially semivolatile compounds, such as sesquiterpenes, but requires a significant investment like that for HSSE. Finally, SPME may be a more appropriate technique for routine quality control due to its operational simplicity, repeatability, and low cost.

Chromatography, Gas↗