Characterization of an easy-to-use method for the routine analysis of the central metabolism using an affordable low-resolution GC-MS system: application to Arthrospira platensis.

We developed an easy-to-use method for the routine analysis of the central metabolism using an affordable low-resolution GC-MS system run in SIM mode. The profiling approach was optimized for the derivatization protocol of some 60 targeted metabolites. The performance of two silylation reagents (MSTFA and BSTFA) that allowed the comprehensive derivatization of 42 key intermediary metabolites of the 60 initially targeted (organic acids, phosphate derivatives, monosaccharides and amino acids) was measured.

Kinetics modeling of alginate alkaline extraction from Laminaria digitata.

Alginates being depolymerized during their alkaline extraction, reducing extraction time could help producing higher rheological quality alginates. The purpose of the present work is to study fresh Laminaria digitata destructuration during alkaline extraction and its link to extraction kinetics. Both alginate extraction yield and mean diameter of algae particles were followed for different values of agitation level and initial size of algae pieces.

DECREASE IN DYNAMIC VISCOSITY AND AVERAGE MOLECULAR WEIGHT OF ALGINATE FROM LAMINARIA DIGITATA DURING ALKALINE EXTRACTION(1).

Alginates are natural polysaccharides that are extracted from brown seaweeds and widely used for their rheological properties. The central step in the extraction protocol used in the alginate industry is the alkaline extraction, which requires several hours. In this study, a significant decrease in alginate dynamic viscosity was observed after 2 h of alkaline treatment.

Anisotropic scattering of light in random media: incoherent backscattered spotlight.

We discuss the anisotropic scattering of unpolarized light in optically dense random media and the flux analysis of an incoherent backscattered spotlight. We present a classic statistical approach based on the photon-diffusion approximation and Monte Carlo simulations to describe the anisotropic propagation of ballistic and long-path photons in a semi-infinite random medium with internal reflections. An imagery technique with high gray-level resolution is used to measure the surface flux density in the incoherent backscattered spotlight.