All the intermediates in the "carboalkoxy" pathway, and their interconversions giving complete catalytic cycles, for palladium-diphosphine-catalyzed hydroalkoxycarbonylation of alkenes, and for alkene-CO copolymerization, have been demonstrated using (31)P{(1)H} and (13)C{(1)H} NMR spectroscopy. The propagation and termination steps of the "hydride" cycles and the crossover between the hydride ...

Synthesis of biodiesel from various plant oils is realized by the transesterification triglycerides with methanol or a reaction usually defined as methanolysis. The usage low-quality oils, such waste cooking oil (WCO), followed undesirable side reactions result increased content free fatty acids (FFA), and water. presence FFA in WCO requires pretreatment stage before subjecting it to In present...

This paper deals with the effect of water and catalyst (KOH) amount on the quantity and quality of transesterification products of rapeseed oil by methanol, the methyl ester phase (i.e. yield, conversion), and the side-product, the glycerol phase (i.e. density, viscosity, the mass fraction of glycerol, esters, soaps). The dependencies were described by statistical models. The transesterificatio...

A method is described for analysis of gangliosides by GLC assay of the sialic acid component. Mild acid treatment in methanol converted the latter to methyl ketoside methyl ester, which was then chromatographed as the TMS derivative. The major methanolysis product was shown to be the beta-anomer, and its chromatographic peak was used for quantification. NANA and NGNA could be analyzed simultane...

The chemical structure of the major conjugate of bilirubin was unequivocally elucidated by structural analysis. The conjugated bilirubins were first separated from the lipid components of human duodenal aspirates or dog gall-bladder bile, and then resolved by t.l.c. into a series of tetrapyrroles. The major tetrapyrrole was then converted into its more stable dipyrrolic azo derivative for furth...

A rapid, accurate microtechnique has been developed for gas chromatographic determination of the fatty acid composition of small (2-3 micro l) samples of vegetable oils. This microtechnique combines transesterification and sample injection into a single operation. The fatty acid compositions of soybean, linseed, and safflower oils thus determined are compared with those obtained by the usual tw...

Isolated eyespot granules of Euglena gracilis Klebs var. bacillaris Pringsheim contained approximately 6% lipids (based on protein). Separation of the lipid extracts by thin layer chromatography revealed four major fractions: wax esters, triacylglycerols, free fatty acids, and phospholipids. Methanolysis of each fraction yielded between 27 and 29 different fatty acids ranging from 12:0 to 22:6....

A sulfated neolactotetraosylceramide has been isolated from the lipid extract of hog gastric mucosa. Isolation procedure involved extraction of lipids with 0.4 M sodium acetate in methanol/chloroform/water, alkaline methanolysis, column fractionation on DEAE-Sephadex, separation of the acetylated acidic glycolipids on silicic acid column, and thin layer chromatography. By partial acid hydrolysi...