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Nonanoic Acid (nonanoic + acid)
Selected AbstractsChemInform Abstract: Efficient and Scalable Methods for ,-Functionalized Nonanoic Acids: Development of a Novel Process for Azelaic and 9-Aminononanoic Acids (Nylon-6,9 and Nylon-9 Precursors).CHEMINFORM, Issue 23 2001Livius Cotarca Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Nonanoic acid , an experimental irritantCONTACT DERMATITIS, Issue 3 2003Jan E. Wahlberg Irritant contact dermatitis is defined as a non-immunological skin reaction following exposure to various chemical, mechanical and physical factors. It is known that the skin response to irritants depends on the irritant applied and differs between chemically different irritants. Sodium lauryl sulfate (SLS) is an anionic detergent and the most frequently used substance in experimental irritant contact dermatitis. In 1980, it was suggested that nonanoic acid (NNA) could be used as a positive control when patch testing. Since then, NNA has been used as an experimental irritant in several studies and has been used as a chemically different substance compared to SLS. The present article presents a review of the application of NNA in studies on skin irritancy and experimental irritant contact dermatitis. [source] Metabolism of Deuterated erythro -Dihydroxy Fatty Acids in Saccharomyces cerevisiae: Enantioselective Formation and Characterization of HydroxylactonesHELVETICA CHIMICA ACTA, Issue 6 2008Leif-A. Abstract Epoxides of fatty acids are hydrolyzed by epoxide hydrolases (EHs) into dihydroxy fatty acids which are of particular interest in the mammalian leukotriene pathway. In the present report, the analysis of the configuration of dihydroxy fatty acids via their respective hydroxylactones is described. In addition, the biotransformation of (±)- erythro -7,8- and -3,4-dihydroxy fatty acids in the yeast Saccharomyces cerevisiae was characterized by GC/EI-MS analysis. Biotransformation of chemically synthesized (±)- erythro -7,8-dihydroxy(7,8- 2H2)tetradecanoic acid ((±)- erythro - 1) in the yeast S. cerevisiae resulted in the formation of 5,6-dihydroxy(5,6- 2H2)dodecanoic acid (6), which was lactonized into (5S,6R)-6-hydroxy(5,6- 2H2)dodecano-5-lactone ((5S,6R)- 4) with 86% ee and into erythro -5-hydroxy(5,6- 2H2)dodecano-6-lactone (erythro - 8). Additionally, the , -ketols 7-hydroxy-8-oxo(7- 2H1)tetradecanoic acid (9a) and 8-hydroxy-7-oxo(8- 2H1)tetradecanoic acid (9b) were detected as intermediates. Further metabolism of 6 led to 3,4-dihydroxy(3,4- 2H2)decanoic acid (2) which was lactonized into 3-hydroxy(3,4- 2H2)decano-4-lactone (5) with (3R,4S)- 5=88% ee. Chemical synthesis and incubation of (±)- erythro -3,4-dihydroxy(3,4- 2H2)decanoic acid ((±)- erythro - 2) in yeast led to (3S,4R)- 5 with 10% ee. No decano-4-lactone was formed from the precursors 1 or 2 by yeast. The enantiomers (3S,4R)- and (3R,4S)-3,4-dihydroxy(3- 2H1)nonanoic acid ((3S,4R)- and (3R,4S)- 3) were chemically synthesized and comparably degraded by yeast without formation of nonano-4-lactone. The major products of the transformation of (3S,4R)- and (3R,4S)- 3 were (3S,4R)- and (3R,4S)-3-hydroxy(3- 2H1)nonano-4-lactones ((3S,4R)- and (3R,4S)- 7), respectively. The enantiomers of the hydroxylactones 4, 5, and 7 were chemically synthesized and their GC-elution sequence on Lipodex®E chiral phase was determined. [source] COMPARISON OF HEADSPACE SOLID PHASE MICROEXTRACTION AND XAD-2 METHODS TO EXTRACT VOLATILE COMPOUNDS PRODUCED BY SACCHAROMYCES DURING WINE FERMENTATIONSJOURNAL OF FOOD QUALITY, Issue 1 2006JEFFRI C. BOHLSCHEID ABSTRACT A modified headspace solid phase microextraction (HS-SPME) method was compared with Amberlite® XAD-2 resin for the extraction of volatile compounds. In the HS-SPME method, volatiles were extracted using an 85 ,m polyacrylate fiber from wines that contained a standardized amount of ethanol (10% v/v), NaCl (0.325 g/mL) and internal standards (dodecanol and nonanoic acid). Both extraction procedures yielded high relative recoveries (>92%) and reproducibilities (coefficient of variations , 11%) for the different higher alcohols, esters and medium-chain fatty acids. Overall, limits of detection for the HS-SPME and XAD-2 methods were below sensory threshold concentrations. HS-SPME and XAD-2 performed similarly in the analysis of a Riesling wine; however, the HS-SPME method did not require organic solvents and was generally quicker to perform. In applying the HS-SPME method, differences in concentrations of volatile compounds produced in Riesling and Chenin blanc wines by 11 different yeast strains were noted. [source] | ||||||||||