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1.
n-Decyl (C10), undecyl (C11), lauryl (C12) and myristyl (C14) alcohols induced nutritional encephalomalacia, when fed to one-day-old White Leghorn male chicks for 3 weeks, while n-heptyl (C7), n-octyl (C8), n-nonyl (C9), cetyl (C16) and stearyl (C18) alcohols did not. Esters of the former group, i.e. n-decyl acetate, lauryl stearate and dilauryl succinate, and aldehydes corresponding to the former group, i.e. n-decyl aldehyde and lauraldehyde, also had the ability to induce encephalomalacia. The disease can be completely prevented by dietary supplementation of dl-β-tocopheryl acetate. Median lethal dietary level of n-decyl and lauryl alcohols and lauraldehyde was estimated to be 20, 18, and 12% respectively.  相似文献   

2.
By using furfuryl mercaptan as the starting material, the following sulfides have been prepared: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, n-amyl, isoamyl, n-hexyl, n-octyl, n-decyl, allyl, prenyl (3-methyl-2-butenyl), benzyl, propargyl, β-hydroxyethyl furfuryl sulfides.

Most of these compounds showed grassy or spicy odor which is distinguishable from the roasted-coffee aroma of furfuryl mercaptan. The infrared spectra of furfuryl alcohol, furfuryl mercaptan and the furfuryl sulfides in carbon tetrachloride have also been compared to find the characteristic absorptions for furfuryl sulfides and a medium band has been detected at 1130 cm?1, which could be useful in identifying furfuryl sulfide group.  相似文献   

3.
《Molecular membrane biology》2013,30(3-4):323-327
An improved synthesis for the nonionic detergent n-octyl-β-D-glucoside (detergent 2) is described. The key modification over earlier methods is the utilization of n-octyl alcohol as the limiting reagent in the condensation between bromide 1 and n-octyl alcohol. A 60-70% overall yield of 2 is obtained without isolation of the intermediate. The β-configuration at the anomeric carbon atom of 2 was confirmed by 100 mHz NMR spectroscopy.  相似文献   

4.
Biological availability of 106 esters of alcohols and aliphatic mono-, di- and tri-carboxylic acids and diethylene glycol succinate was compared by the mini-test with chicks. Chicks can utilize methyl esters of saturated fatty acids of carbon chain from 10 to 14, ethyl esters of those from 9 to 12, propyl caprate, n-butyl esters of those from 8 to 12, n-amyl esters of those from 6 to 12, n-hexyl n-butyrate and i-vaterate, and n-octyl and n-decyl acetates. Only 3 dicarboxylates, i.e. di-octyl and di-lauryl succinates and di-methyl cis-cyclopropane-l,2-dicarboxylate, were available among the dicarboxylates tested. Availability of ethyl esters of succinic, fumaric and citric, acid was unexpectedly low.  相似文献   

5.
Susceptibility to hydrogen peroxide of the erythrocytes from chicks and rats fed dilauryl succinate and related compounds with and without supplementation of dl-α-tocopheryl acetate was determined.

Dilauryl succinate, lauryl alcohol, n-decyI alcohol, myristyl alcohol, and lauraldehyde were confirmed to make the erythrocytes from the chicks fragile. Supplemented dl-α-tocopheryl acetate of 200 mg per kg of diet completely prevented the hemolysis induced by these compounds. Dilauryl succinate also makes the rat’s erythrocytes fragile and supplemented dl-α-tocopheryl acetate prevented the hemolysis of the rats, but ethoxyquin was not. The symptoms of encephalomalacia in the chick is preceded by increased hemolysis value of the erythrocytes, and this hemolysis value dropped after the appearance of encephalomalacia.  相似文献   

6.
Low-boiling compounds escaping during steam distillation of Cryptotaenia japonica Hassk were collected and examined with chromatographies and by the preparation of their derivatives.

The following compounds were identified. Six paraffin hydrocarbons: n-pentane, n-hexane, n-heptane, n-octane, isooctane, n-nonane; seven carbonyl compounds: formaldehyde, acetaldehyde, propionaldehyde, n-butyraldehyde, isovaleraldehyde, acetone, 3-methyl-2-pentanone; three esters: n-propyl and isopropyl formates, n-propyl acetate; eight alcohols: methanol, ethanol, n-propanol, isopropanol, isobutanol, sec-butanol, isopentanol, n-octanol; two sulfides: dimethyl and methyl ethyl sulfides; six monoterpene hydrocarbons: α-pinene, camphene, β-pinene, sabinene, myrcene, limonene.  相似文献   

7.
The following steroids and steroidal alkaloids have been incubated with the blight fungus Phytophthora infestans: androst-4-ene-3,17-dione, cholesterol, cholesteryl acetate, cholesteryl myristate, cholesteryl palmitate,cholesteryl stearate, dehydroisoandrosterone, 6α-hydroxy-androst-4-ene-3,17-dione, 6β-hydroxyandrost-4-ene-3,17-dione, 11α-hydroxyprogesterone, pregnenolone, progesterone, sitosterol, sitosteryl acetate, solanidine, solanine, stigmasterol, stigmasteryl acetate and testosterone. No hydroxylation was observed, but the fungus is able to oxidize alcohol functions at C-3β, C-6α, C-11β and C-17β to carbonyl. In addition, hydrolysis of acetate to hydroxyl at C-3β, and of solanine to solanidine, was observed. The relationship between metabolism and the nature of substitution at C-17β is discussed.  相似文献   

8.
Summary In the final step of the pathway producing ethanol in anoxic crucian carp (Carassius carassius L.), acetaldehyde is reduced to ethanol by alcohol dehydrogenase. The presence of aldehyde dehydrogenase in the tissues responsible for ethanol production could cause an undesired oxidation of acetaldehyde to acetate coupled with a reduction of NAD+ to NADH. Moreover, acetaldehyde could competitively inhibit the oxidation of reactive biogenic aldehydes. In the present study, the distribution of aldehyde dehydrogenase (measured with a biogenic aldehyde) and alcohol dehydrogenase (measured with acetaldehyde) were studied in organs of crucian carp, common carp (Cyprinus carpio L.), rainbow trout (Salmo gairdneri Richardson), and Norwegian rat (Rattus norvegicus Berkenhout). The results showed that alcohol dehydrogenase and aldehyde dehydrogenase activities were almost completely spatially separated in the crucian carp. These enzymes occurred together in the other three vertebrates. In the crucian carp, alcohol dehydrogenase was only found in red and white skeletal muscle, while these tissues contained exceptionally low aldehyde dehydrogenase activities. Moreover, the low aldehyde dehydrogenase activity found in crucian carp red muscle was about 1000 times less sensitive to inhibition by acetaldehyde than that found in other tissues and other species. The results are interpreted as demonstrating adaptations to avoid a depletion of ethanol production, and possibly inhibition of biogenic aldehyde metabolism.Abbreviations ADH alcohol dehydrogenase - ALDH aldehyde dehydrogenase - DOPAL 3,4-dihydroxyphenylacetaldehyde - MAO monoamine oxidase - PCA perchloric acid  相似文献   

9.
Semisynthetic functionalized triterpenes (4α,14‐dimethyl‐5α,8α‐8,9‐epoxycholestan‐3β‐yl acetate; 4α,14‐dimethyl‐5α‐cholest‐8‐ene‐3,7,11‐trione; 4α,14‐dimethyl‐5α‐cholesta‐7,9(11)‐dien‐3‐one and 4α,14‐dimethyl‐5α‐cholest‐8‐en‐3β‐yl acetate), previously prepared from 31‐norlanostenol, a natural insecticide isolated from the latex of Euphorbia officinarum, have been subjected to oxidation with hydrogen peroxide (H2O2) and iodosobenzene (PhIO) catalyzed by porphyrin complexes (cytochrome P‐450 models) in order to obtain optimized derivatives with high regioselectivity. The main transformations were epoxidation of the double bonds and hydroxylations of non‐activated C–H groups and the reaction products were 25‐hydroxy‐4α,14‐dimethyl‐5α‐cholesta‐7,9(11)‐dien‐3β‐yl acetate (59 %), 25‐hydroxy‐4α,14‐dimethyl‐5α‐cholest‐8‐ene‐3,7,11‐trione (60 %), 4α,14‐dimethyl‐5α,7β‐7,8‐epoxycholest‐9(11)‐en‐3‐one (22 %), 8‐hydroxy‐4α,14‐dimethyl‐5α‐cholest‐9(11)‐ene‐3,7‐dione (16 %), 12α‐hydroxy‐4α,14‐dimethyl‐5α,7β‐7,8‐epoxycholest‐9(11)‐en‐3‐one (16 %), and 4α,14‐dimethyl‐5α,8α‐8,9‐epoxycholestan‐3β‐yl acetate (26 %), respectively. We also investigated the insect (Myzus persicae, Rhopalosiphum padi and Spodoptera littoralis) antifeedant and postingestive effects of these terpenoid derivatives. None of the compounds tested had significant antifeedant effects, however, all were more effective postingestive toxicants on S. littoralis larvae than the natural compound 31‐norlanostenol, with 4α,14‐dimethyl‐5α,8α‐8,9‐epoxycholestan‐3β‐yl acetate being the most active. The study of their structure–activity relationships points out at the importance of C3 and C7 substituents.  相似文献   

10.
The needle‐terpene profiles of two natural Pinus peuce populations from the Scardo‐Pindic mountain system (Mt. O?ljak and Mt. Pelister) were analyzed. Among the 90 detected compounds, 87 were identified. The dominant constituents were α‐pinene (45.5%), germacrene D (11.1%), β‐pinene (10.8%), and camphene (10.3%). The following eight additional components were found to be present in medium‐to‐high amounts (0.5–10%): bornyl acetate (5.0%), β‐phellandrene (3.4%), β‐caryophyllene (2.9%), β‐myrcene (0.9%), germacrene D‐4‐ol (0.9%), tricyclene (0.7%), (E)‐hex‐2‐enal (0.7%), and bicyclogermacrene (0.6%). Although the general needle‐terpene profiles of the populations from Mt. O?ljak and Mt. Pelister were found to be similar to those of the populations from Zeletin, Sjekirica, and Mokra Gora (Dinaric Alps), principle component analysis (PCA) of eight terpenes (α‐pinene, β‐myrcene, α‐terpinolene, bornyl acetate, α‐terpinyl acetate, β‐caryophyllene, transβ‐farnesene, and germacrene D) in 139 tree samples suggested a divergence between the two population groups, i.e., the samples from the Scardo‐Pindic mountain system and those from the Dinaric Alps. Genetic analysis of the β‐pinene content demonstrated a partial divergence between the two geographical groups. The profiles of both population groups differed from those published for populations from the Balkan‐Rhodope mountains system (literature results), which were characterized by high contents of bornyl acetate and citronellol (Greek populations) or δ‐car‐3‐ene (Bulgarian populations).  相似文献   

11.
α-Pinene, terpinolene, δ-elemene, α-copaene, α- and β-humulene, β-sesquiphellandrene, γ-cadinene, acetate of p-menthen-1-ol-9 and acetate of p-menthadien-1, 8(10)-ol-9 were newly identified as the volatile constituents of peel oil from C. Unshiu. Aroma characteristics of C. Unshiu are discussed on the basis of quantitative analysis.

Comparison of aroma patterns of peel oil among various citrus fruits was also carried out with head space analysis.  相似文献   

12.
We have found that some straight-chained α-amino acids are converted by yeast to the alcohols with correspondingly longer carbon chains in the alcoholic fermentation contrary to F. Ehrlich’s scheme, i.e., isobutyl alcohol from alanine and active amyl alcohol from α-amino-n-butyric acid or threonine.

In this report, we confirmed this fact in the alcoholic fermentation of many aliphatic amino acids by 2 yeast strains using gas chromatography. Moreover, n-propyl alcohol was proved to come from α-amino-n-butyric acid or threonine. Small quantities of n-propyl, isobutyl, active amyl and isoamyl alcohols were found in all the fermented solutions. There was some difference in the composition of higher alcohols of the alcoholic solutions fermented by different yeasts.  相似文献   

13.
The chemical composition of 50 samples of leaf oil isolated from Algerian Juniperus phoenicea var. turbinata L. harvested in eight locations (littoral zone and highlands) was investigated by GC‐FID (in combination with retention indices), GC/MS, and 13C‐NMR analyses. The composition of the J. phoenicea var. turbinata leaf oils was dominated by monoterpenes. Hierarchical cluster and principal component analyses confirmed the chemical variability of the leaf oil of this species. Indeed, three clusters were distinguished on the basis of the α‐pinene, α‐terpinyl acetate, β‐phellandrene, and germacrene D contents. In most oil samples, α‐pinene (30.2–76.7%) was the major compound, associated with β‐phellandrene (up to 22.5%) and α‐terpinyl acetate (up to 13.4%). However, five out of the 50 samples exhibited an atypical composition characterized by the predominance of germacrene D (16.7–22.7%), α‐pinene (15.8–20.4%), and α‐terpinyl acetate (6.1–22.6%).  相似文献   

14.
Neutral constituents of volatiles in the ether extract of cultured broth of Sporobolomyces odorus AHU 3246 were analyzed by gas chromatography-mass spectrometry and other methods.

Identified compounds were as follows: Methyl, ethyl, isobutyl, n-butyl, isoamyl, n-amyl, benzyl, and β-phenylethyl alcohol; formaldehyde, acetaldehyde, benzaldehyde, phenyl-acetaldehyde, acetone, and methyl ethyl ketone; ethyl formate, ethyl acetate, and di-n-butyl phthalate; γ-decalactone (4-decanolide) and 4-hydroxy-cis-dodecenoic acid γ-lactone (cis-6-dodecen-4-olide). Di-n-butyl phthalate and parts of methyl, ethyl, and n-butyl alcohol and ethyl acetate were thought to be contaminants. γ-Lactones produced by the yeast were determined by GLC.

Although nine strains of six species of carotenoid pigment accumulating yeasts were cultured under the same conditions, neither flavorful smelling nor γ-lactone production detected in their cultured broths.  相似文献   

15.
α-Hydroxyisobutyraldehyde, one of model compounds for α-aldol structure of streptose moiety of strpetomycin, was reduced at controlled-potential mercury cathode to give isobutyl alcohol and 1,1-dimethylethyleneglycol. Reduction ratio of α-hydroxyl group was dependent on the cathode potential and pH, as was seen in the reduction of streptomycin. Results of reduction of α-hydroxyisobutyraldehyde with sodium or aluminum amalgam suggests that their mode of action on the aldehyde is determined by the magnitudes of negative potential that they respectively retain in the reaction media, and by pH, as in the cases of electroreduction. Isobutyraldehyde was isolated as an intermediate product of reduction to isobutyl alcohol, in both cases.  相似文献   

16.
Summary An enriched mixed culture was successfully grown on model alkyl and aryl carbonates. These compounds were degraded by microorganisms at different rates.P-Chlorophenyl-2-octyl carbonate andp-nitrobenzyl-2-octyl carbonate were metabolized through the formation ofp-chlorophenol andp-nitrobenzyl alcohol respectively. A strain ofAcinetobacter calcoacefcus isolated from the mixed culture utilized phenyl-2-octyl carbonate by an intracellular hydrolase to phenol and 2-octanol which were further metabolized.  相似文献   

17.
Alcohol dehydrogenase is necessary for ethanol detoxification and metabolic utilization. It has been generally assumed that aldehyde oxidase (AO) produced by the Aldox locus (3–56.7) is necessary for a further transformation of acetaldehyde into acetate. We find that various mutant strains (ma-l or Aldox n) which do not produce an active enzyme show about the same tolerance to alcohol as do wild strains. This physiological paradox is probably to be explained by the discovery of another locus (not localized) which produced a small amount of AO in all tested strains. The adaptive significance of the genetically polymorphic Aldox locus is probably to be looked for in physiological pathways other than ethanol metabolism.  相似文献   

18.
《Process Biochemistry》2010,45(5):700-705
A highly thermostable recombinant xylanase from Thermotoga neapolitana was used as a catalyst for single-step synthesis of n-octyl xylobioside and n-octyl xylotrioside from xylan and n-octanol. Effect of xylan concentration, enzyme dose, reaction water content, reaction temperature and initial pH on the yield of these surfactants has been studied. The optimal conditions for n-octyl xylobioside and n-octyl xylotrioside synthesis are found to be different. The maximum n-octyl xylobioside and n-octyl xylotrioside yield were 120 and 38 mg/g of xylan, respectively. The n-octyl xylobioside yield achieved in this study was better than the yield achieved in all other enzymatic synthesis studies reported so far except what is achieved with the use of supercritical fluoroform under high pressure. The n-octyl xylotrioside yield is the highest ever achieved through enzymatic synthesis. An integrated system of production and recovery of n-octyl xylosides has improved the yield of n-octyl xylobioside and n-octyl xylotrioside by a factor of 1.7 and 2.4, respectively.  相似文献   

19.
20.
This study examined the effects of β‐carotene on antioxidant status in rats with chronic alcohol consumption. At the beginning of experiment (week 0), according to both the plasma aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities, rats (n = 24) were divided into 3 groups and fed with a standard diet (group C), a diet containing ethanol (group E), or a diet containing ethanol and β‐carotene (group E+B). After 10 weeks, plasma AST and ALT, fat accumulation in the liver, antioxidant enzyme activities in erythrocytes and the liver, malondialdehyde (MDA), and α‐tocopherol and retinol in plasma and hepatic samples were analyzed. The chronic alcohol diet significantly increased AST and ALT levels in plasma, and these changes were prevented by supplementing the diet with β‐carotene. Glutathione (GSH) in erythrocytes and in the liver was significantly elevated in rats fed with a diet containing β‐carotene. The results indicate that β‐carotene supplementation can prevent ethanol‐induced liver damage and increase GSH concentrations in erythrocytes and the liver. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

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