Vibrational spectroscopic investigations of hydrocarbon chain ordering in phosphatidylcholines (PCs) adsorbed from aqueous solution to a carbon tetrachloride-water interface presented here examine on a molecular level the organization pertinent to the surface characteristics displayed by these films. In a series of saturated symmetric and asymmetric chain PCs, both symmetric PCs with 16 or fewe...

Biosurfactant are surface active compounds produced by microorganisms. These molecules reduce surface tension between aqueous solutions and hydrocarbon mixtures. Hundred hydrocarbon saturated soil samples were collected from thirty different areas in Chennai, TamilNadu, India. Seventy two bacterial strains were isolated and cultured by enriching carbon (Glycerol) source. Each culture medium was...

Optimization of the light conditions for biofuel production by the microalga Botryococcus braunii BOT-22 (race B) was performed using monochromatic red light. The lipid and sugar contents were approximately 40% and 20-30% of the cell dry weight, respectively, and about half of the lipids were liquid hydrocarbons. The half-saturation intensities for the production rate of lipids, hydrocarbons, a...

A mechanism of the solute retention in gas-liquid chromatography has been studied in the nonpolar hydrocarbon solute-polar stationary liquid phase system. N,N,N',N'-tetrakis(2-hydroxyethyl)ethylene diamine (THEED) was used as a polar stationary liquid phase. A dependence of the retention volume of the solutes and of the specific surface area of the liquid-coated, modified alumina upon the liqui...

Lipids were extracted from cells of Pseudomonas aeruginosa grown on a pure hydrocarbon (tridecane), mixed hydrocarbons (JP-4 jet fuel), and on Trypticase Soy Broth. Total lipids produced from each substrate represented from 7.1 to 8.2% of cellular dry weight, of which 5.0 to 6.4% were obtained before cellular hydrolysis (free lipids) and 1.7 to 2.0% were extracted after cellular hydrolysis (bou...

Cell membranes contain small domains (on the order of nanometers in size, sometimes called rafts) of lipids whose hydrocarbon chains are more ordered than those of the surrounding bulk-phase lipids. Whether these domains are fluctuations, metastable, or thermodynamically stable, is still unclear. Here, we show theoretically how a lipid with one saturated hydrocarbon chain that prefers the order...

Strains of hydrocarbon-degrading microorganisms (bacteria and fungi) were isolated from an agricultural soil in France. In a field, a portion was treated with oily cuttings resulting from the drilling of an onshore well. The cuttings which were spread at the rate of 600 g HC m-2 contained 10% of fuel oil hydrocarbons (HC). Another part of the field was left untreated. Three months after HC spre...

The structural parameters of fluid phase bilayers composed of phosphatidylcholines with fully saturated, mixed, and branched fatty acid chains, at several temperatures, have been determined by simultaneously analyzing small-angle neutron and X-ray scattering data. Bilayer parameters, such as area per lipid and overall bilayer thickness have been obtained in conjunction with intrabilayer structu...