CIEL*a*b* color space predictive models for colorimetry devices--analysis of perfume quality.

Color perception plays a major role in the consumer evaluation of perfume quality. Consumers need first to be entirely satisfied with the sensory properties of products, before other quality dimensions become relevant. The evaluation of complex mixtures color presents a challenge even for modern analytical techniques.

Antifouling activity of meroditerpenoids from the marine brown alga Halidrys siliquosa.

Nine tetraprenyltoluquinol-related metabolites (1-9) have been isolated from the organic extract of the temperate brown alga Halidrys siliquosa that exhibits antifouling properties. The planar structure of compounds 1-9 was elucidated on the basis of extensive spectroscopic analysis and by comparison of the data with those of related metabolites. Antifouling and toxicity tests were conducted on these compounds: the most active (compounds 2, 6, and 9) inhibited both the growth of four strains of bacteria (MICs < 2.

Comparison of various extraction methods for identification and determination of volatile metabolites from the brown alga Dictyopteris membranacea.

Three different methods: hydrodistillation (HD), focused microwave-assisted hydrodistillation (FMAHD) and supercritical fluid extraction (SFE) have been applied, for the first time together, for the extraction of volatile metabolites of the brown alga Dictyopteris membranacea. The oils obtained were analyzed by GC-MS (identification and determination of metabolites) and the results were compared. The main chemical classes of compounds identified were C11 hydrocarbons for HD method, sesquiterpenes for FMAHD method and sulphur compounds for SFE method.

Polar acyclic diterpenoids from Bifurcaria bifurcata (Fucales, Phaeophyta).

From the lipophilic extract of the brown alga Bifurcaria bifurcata collected off the Atlantic coast of Southern Brittany (Quiberon, France), five polar linear diterpenoids have been isolated. These metabolites have been identified as hydroxylated derivatives of 13-oxo- and 13-hydroxygeranylgeraniol. Their structures were characterized on the basis of chemical and spectral evidence including two-dimensional NMR experiments and mass spectrometric techniques.

Trihydroxylated linear diterpenes from the brown alga Bifurcaria bifurcata.

Two novel polar diterpenes were isolated from the brown alga Bifurcaria bifurcata collected off the Atlantic coast of Morocco, and their structures established by spectral methods. Both compounds are trihydroxylated acyclic diterpenes derived from 12-hydroxygeranylgeraniol. They were tested in vitro for their cytotoxicity and proved to be active against the NSCLC-N6 cell line.