Assuntos
Doenças dos Bovinos/etiologia , Micotoxinas/toxicidade , Fosfatase Alcalina/sangue , Ração Animal/efeitos adversos , Animais , Aspartato Aminotransferases/sangue , Análise Química do Sangue , Proteínas Sanguíneas/análise , Bovinos , Doenças dos Bovinos/diagnóstico , Colesterol/sangue , L-Lactato Desidrogenase/sangue , Fosfatos/sangue , Intoxicação por Plantas/veterinária , Poaceae , Zea maysAssuntos
Doenças dos Bovinos/microbiologia , Fusarium/metabolismo , Micotoxinas/biossíntese , Animais , Bovinos , Feminino , MasculinoAssuntos
Lipase , Óleos , Fenômenos Químicos , Química , Glicerídeos , Cinética , Pâncreas/enzimologia , Plantas , Sementes , TriglicerídeosAssuntos
Benzopiranos/análise , Inseticidas/análise , Plantas/análise , Rotenona/análise , DensitometriaRESUMO
Coriolic [(R)-13-hydroxy-cis-9,trans-11-octadecadienoic] acid (III, R=Z=H) was isolated as the methyl ester from twoCoriaria seed oils in 66 and 68% yields. The double bonds and hydroxyl group were located by periodate-permanganate oxidation before, and chromic acid oxidation after, hydrogenation of the double bonds. Alternatively the positions of the functional groups were indicated by a convenient micro-ozonolysis-gas-liquid chromatographic procedure. Determination of products from partial hydrolysis of theCoriaria oils with pancreatic lipase (EC 3.1.1.3) revealed a preference of the corioloyl group for the 1,3-positions in triglyceride molecules. The possible significance of coriolic acid as an intermediate in the biogenetic conversion of linoleic acid to conjugated trienoic acids is discussed.
RESUMO
When bis(trimethylsilyl)acetamide is used to silylate lipolysates for gas-liquid chromatography, the pyridine solution containing the sample and silylating agent can be injected directly onto the column. Conversion of free fatty acids to methyl esters before silylation is unnecessary, since silyl esters elute as sharp gas-liquid chromatographic peaks.
Assuntos
Óleos/análise , Plantas/análise , Cromatografia Gasosa , Ácidos Graxos/análise , Métodos , Extratos Vegetais/análise , Sementes/análise , SiliconesRESUMO
New high-epoxy vegetable oils from nine species representing three plant families and four genera have been investigated. The epoxyacyl moiety in at least one oil from each genus was characterized and shown to be the (+)-vernoloyl (cis-12,13-epoxy-cis-9-octadecenoyl) group. Intraglyceride distribution studies revealed a general preference of the (+)-vernoloyl groups for the beta-position of triglyceride molecules. Interglyceride distribution of (+)-vernoloyl groups was studied in three oils and found not to agree with predictions based on either 1,2,3-random or 1,3-random-2-random distribution. A striking exception to the general intraglyceride distribution pattern was discovered in the monoepoxy triglyceride fraction fromEuphorbia lagascae seed oil.
RESUMO
A convenient and rapid procedure involving methylation, silylation, and temperature-programmed gas-liquid chromatography (GLC) is described for analyzing unfractionated products from the hydrolysis of triglycerides with pancreatic lipase. The conditions employed for GLC were selected to provide maximum and rapid separation of silylated monoglycerides in which the acyl moieties differ in chain length or degree of substitution with oxygen-containing functional groups. Derivatives differing only in the number of double bonds present were not separated. In the GLC curves obtained, peaks representing methyl esters are generally readily distinguishable from those of other components. Therefore, the extent of lipolysis and the composition (with respect to chain length and substitution of acyl groups) of monoglycerides formed are determined simultaneously. The accuracy of the new method was demonstrated with standard mixtures and by comparison of results for several lipolysis products with data obtained by conventional procedures.
