Search results for "acids"
showing 10 items of 3520 documents
The Influence of Acetylcholine and Choline on the Incorporation of Phosphate into Phospholipids of Etiolated Bean Hypocotyl Hooks
1980
Summary Acetylcholine influenced the radiolabelling of phospholipids in vivo in etiolated hypocotyl tissue of dwarf beans in darkness. Under aerobic conditions the specific activity of the phospholipids was decreased and under anaerobic conditions increased. The biosynthesis of phospholipids was strongly increased by the bivalent cations calcium and manganese and decreased by 2,4-dinitrophenol, anaerobiosis, atropine and ascorbic acid. Magnesium stimulated the uptake of the radioactive phosphate but not the specific activity of the phospholipids. The results are discussed in comparison with the «phospholipid-effect» of acetylcholine in animal tissues.
Mixtures of lecithin with polymerizable derivatives of cholesterol. A monolayer film balance study.
1986
One of the best investigated binary lipid mixtures is the lecithin-cholesterol system. We show here that it is possible to modify the cholesterol in such a way that it can be polymerized without changing its behaviour in mixtures with lecithin. The polymerizable derivatives exhibit a very similar phase diagram in the mixture with dipalmitoyl-phosphatidylcholine as the cholesterol itself. This is demonstrated by filmbalance measurements.
Modular Small Diameter Vascular Grafts with Bioactive Functionalities.
2015
We report the fabrication of a novel type of artificial small diameter blood vessels, termed biomimetic tissue-engineered blood vessels (bTEBV), with a modular composition. They are composed of a hydrogel scaffold consisting of two negatively charged natural polymers, alginate and a modified chitosan, N,O-carboxymethyl chitosan (N,O-CMC). Into this biologically inert scaffold two biofunctionally active biopolymers are embedded, inorganic polyphosphate (polyP) and silica, as well as gelatin which exposes the cell recognition signal, Arg-Gly-Asp (RGD). These materials can be hardened by exposure to Ca(2+) through formation of Ca(2+) bridges between the polyanions, alginate, N,O-CMC, and polyP…
Identification by GC-FID and GC-MS of amino acids, fatty and bile acids in binding media used in works of art.
2001
GC-FID was used as single methodology for the identification and differentiation of proteins, lipids and ox bile from binders used in artistic paintings. The samples were hydrolyzed by HCl. Subsequently, the simultaneous formation of volatile derivatives of the amino, fatty and bile acids with ethyl chloroformate was performed quickly and safely in an aqueous medium. The derivatives were separated by capillary GC and characterized by GC-MS. The ageing of drying oils was studied, identifying pelargonic acid among other degradation products. Proteinaceous and lipoid binding media were characterized by means of the quotients between the areas of the peaks for each amino or fatty acid with resp…
Gas chromatographic and mass spectrometric characterization of the organic acids extracted from some preparations containing lyophilized royal jelly.
2009
Thirty-five aliphatic acids were identified by gas chromatography-mass spectrometry from the ether extract of commercial preparations containing lyophilized royal jelly. The article presents linear-programmed retention indices on capillary columns with non-polar and low-polar stationary phases and mass spectra for identified compounds which were not characterized earlier by these parameters. Nine compounds are reported for the first time as royal jelly constituents.
Role of dioxygenase α-DOX2 and SA in basal response and in hexanoic acid-induced resistance of tomato (Solanum lycopersicum) plants against Botrytis …
2015
Resistance of tomato (Solanum Lycopersicum) to the fungal pathogen Botrytis cinerea requires complex interplay between hormonal signalling. In this study, we explored the involvement of new oxylipins in the tomato basal and induced response to this necrotroph through the functional analysis of the tomato α-dioxygenase2 (α-DOX2)-deficient mutant divaricata. We also investigated the role of SA in the defence response against this necrotrophic fungus using SA-deficient tomato nahG plants. The plants lacking dioxigenase α-DOX2, which catalyses oxylipins production from fatty acids, were more susceptible to Botrytis, and hexanoic acid-induced resistance (Hx-IR) was impaired; hence α-DOX2 is requ…
Microstructure and characteristic properties of dogfish skin gelatin gels prepared by freeze/spray-drying methods
2020
International audience; The effects of two pretreatments (microwaves or oven-drying) on the dogfish (Squalus acanthias) skin as well as two drying processes (freeze-drying or spray-drying) on the extracted gelatins were studied. Thus six types of gelatins were obtained, three of which were freeze-dried (FG) and the others were spray-dried (SG), from the untreated skin (US), microwaves-pretreated skin (MS) and oven-pretreated skin (OS). The highest yield (8.67%) was obtained for the OSFG, while the lowest one (3.06%) was measured for the OSSG. Interestingly, all gelatins exhibited relatively high protein (84.02-89.53%), and low lipid (0.50-1.71%) and ash (3.05-7.17%) contents. In addition, g…
Evolution of Trans‐ fatty acid consumption in Thailand and strategies for its reduction
2020
Eliminating industrially produced trans-fatty acids (TFAs) from the food supply is one of the World Health Organization's (WHO's) priority targets to control and prevent non-communicable diseases. This review paper describes the strategies used to reduce TFA consumption in Thailand based on a situation analysis consisting of an assessment of TFA content in the national food supply, its intake, and stakeholder-based analysis of Strengths, Weaknesses, Opportunities, and Threats (SWOT). The analysis resulted in the drafting of a regulatory approach, which was then considered by stakeholders. Bakery products containing partially hydrogenated oils (PHOs) are the major sources of TFAs in Thailand…
Structural behaviour differences in low methoxy pectin solutions in the presence of divalent cations (Ca 2+ and Zn 2+ ): a process driven by the bind…
2014
International audience; In this paper, we compare the interactions between low methoxy pectin (LMP) and either Ca2+ or Zn2+ in semi-dilute solutions. Intrinsic viscosity and turbidity measurements reveal that pectin-calcium solutions are more viscous, but yet less turbid, than pectin-zinc ones. To get a molecular understanding on the origin of this rather unexpected behavior, we further performed isothermal titration calorimetry, small angle neutron scattering experiments, as well as molecular dynamics simulations. Our results suggest that calcium cations induce the formation of a more homogeneous network of pectin than zinc cations do. The molecular dynamics simulations indicate that this …
Biocatalyzed acidolysis of soybean oil triacylglycerols to increase oleic acid content
2004
Lipase catalyzed acidolysis of triacylglycerols (TAG) of soybean oil with oleic acid in organic solvent was studied; immobilized lipase from Rhizomucor miehei was used and the effects of reaction time, incubation temperature and enzyme load on TAG total and positional fatty acid (FA) percentage compositions were investigated. The results show that oleic acid incorporation was high after 24 and 48 h, while after 72 h a lower level of oleic acid in TAG was observed. Moreover, for the reactions carried out at 30 and 40 degrees C, it was observed that the oleic acid level was about 46.5% while ligtly higher values (about 49%) were observed at 50 degrees C; however, under this last condition, th…