Recovery of valuable soluble compounds from washing waters generated during small fatty pelagic surimi processing by membrane processes.

This work focuses on the treatment of washing waters coming from surimi manufacturing using ultrafiltration technology at a laboratory scale. Four membrane materials (poly-ether sulfone, polyacrilonytrile, poly vinylidene fluoride and regenerated cellulose) and 5 Molecular Weight Cut-Off (from 3 to 100 kDa) have been studied at bench laboratory scale using the pilot Rayflow 100, commercialised by Rhodia Orelis. The investigation deals with the ability for membranes to offer a high retention of biochemical compounds (proteins and lipids). Results obtained during adsorption tests showed that the regenerated cellulose material seems to be the most appropriate with regards to pore size reduction due to the protein-adsorption. During the ultrafiltration of the washing water, the regenerated cellulose material leads to the best results, followed by the polyacrylonitrile and poly-vinylidene fluoride materials. Poor results were obtained with polyether sulfone membrane. Compared to the other materials, the regenerated cellulose is the easiest to regenerate, with minimal cleaning water and no chemical treatment necessary. Biochemical characterization of the fractions generated during the ultrafiltration with the polyacrilonytrile, poly vinylidene fluoride and regenerated cellulose membranes showed that all the membranes provided a high recovery rate of the lipids and proteins. The 10 kDa regenerated cellulose membrane had the highest performance and was further evaluated. With such a treatment, the chemical oxygen demand was reduced by 75%. By performing hydrolysis followed by a centrifugation, biochemical composition of the sludge and liquid fraction were modified, producing an insoluble fraction containing fats and few proteins and a soluble fraction containing proteins and few fats. The sludge, initially insoluble, was mainly solubilized during hydrolysis, and lipids and peptides were concentrated by ultrafiltration.

Sulfated compounds from marine organisms.

More than 500 sulfated compounds have been isolated from marine organisms so far but most of them originate from two phyla only, Spongia and Echinodermata. The sulfated compounds are presented according to the phyla they have been identified from and to their chemical structures. Biological activities, when available, are also given. Macromolecules have also been included in this review but without structural details.

New unsaturated long-chain fatty acids in the phospholipids from the Axinellida sponges Trikentrion loeve and Pseudaxinella cf. lunaecharta.

In order to identify new structures and especially those involved as biosynthetic intermediates, the fatty acid composition of whole phospholipids from two Senegalese marine sponges from the order Axinellida, Trikentrion loeve and Pseudaxinella cf. lunaecharta, has been investigated by analytical gas chromatography and gas chromatography/mass spectrometry. Several new fatty acids were identified as methyl esters and N-acyl pyrrolidides, namely 16-eicosenoic, 11-tetracosenoic, 5-pentacosenoic, 11-hexacosenoic, 11-octacosenoic, 23-triacontenoic, 17,21-hexacosadienoic, 19,23-octacosadienoic, 9,23-triacontadienoic, 5,9,21-hexacosatrienoic, and 5,9,25-triacontatrienoic. Trikentrion loeve and P. cf. lunaecharta contain fifteen (25.7% of the total acid mixture) and thirteen (30.4%) delta 5,9 fatty acids, respectively. Based on gas chromatography/Fourier transform infrared experiments, the double bonds were assigned the (Z) configuration. Biosynthesis of dienoic and trienoic demospongic acids possessing an n-5 or an n-7 terminal double bond is discussed.

Phospholipid FA from Indian Ocean tunicates Eudistoma bituminis and Cystodytes violatinctus.

Two tunicates (Eudistoma bituminis and Cystodytes violatinctus, family Polycitoridae) were investigated for the FA content of their phospholipids. GC-MS analysis of their methyl esters and N-acyl pyrrolidides revealed 40 FA in E. bituminis, and 26 in C. violatinctus. In both cases, the most abundant FA were the saturated ones (C10 to C18). Cystodytes violatinctus contained considerable oleic acid (20%). Both E. bituminis and C. violatinctus contained phytanic acid and delta10-unsaturated FA, which had not previously been found in such organisms. The two tropical tunicates contained only trace amounts of PUFA, which are usually predominant in this phylum.

New branched-chain fatty acids from the Senegalese gorgonian Leptogorgia piccola (white and yellow morphs).

Fatty acids from total lipids of the gorgonian Leptogorgia piccola (white and yellow morphs), collected from the same area at two different periods with regard to the average water temperature, were studied. More than fifty fatty acids were identified as methyl esters and N-acyl pyrrolidides by gas chromatography and gas chromatography/mass spectrometry. Three new, branched-chain unsaturated fatty acids were identified in addition to the unusual 7-methyl-6-hexadecenoic acid, namely 10-methyl-6-hexadecenoic, 7,9-dimethyl-6-hexadecenoic, and 10-methyl-6,9-heptadecadienoic acids. Also 6,9-heptadecadienoic acid was identified. The fatty acid patterns of specimens harvested in colder waters were quite different from those harvested in warmer waters in that the former contained high amounts of methylene-interrupted polyunsaturated acids, including tetracosapolyenoic acids, especially 6,9,12,15,18-24:5 (up to 15.8% of the total acid mixture) and 6,9,12,15,18,21-24:6 (up to 5.3%). Arachidonic acid was, nevertheless, a major component in all the fatty acid mixtures studied (13.6-20.5%). Based on gas chromatography/Fourier transform infrared experiments, the double bonds were assigned the (Z) configuration. Several fatty aldehydes and their dimethyl acetals were also detected, of which the most abundant was octadecanal.