Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Caprylates”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 397 records · Page 22Linked to original sources
PubMedDate not supplied

Hemagglutination enhancement by bovine serum albumin is affected by octanoate, Reactive Blue 2 (Cibacron Blue), and polymer.

An AutoAnalyzer system was used to study factors that influence the albumin enhancement of agglutination of Rh(D)-positive red cells by IgG anti-D. An albumin consisting of trimer and higher oligomer was more efficient than a preparation composed mainly of monomer and dimer. Modification of the hemagglutination-enhancing property of albumin was obtained by the addition of ligands (octanoate [caprylate] and Reactive Blue 2 [Cibacron Blue]). Irrespective of the polymer content, neither ligand alone had any effect on low-fatty-acid albumins. However, when mixtures of octanoate and Cibacron Blue were added to the same albumins, hemagglutination was initially increased, and then diminished with increasing concentrations of ligands. The enhancing property of high-fatty-acid, nonpolymerized albumin was markedly reduced by the addition of octanoate or Cibacron Blue. On the other hand, only Cibacron Blue could produce the same inhibitory effect on a polymerized albumin with high fatty acid content. The implication is that the total free fatty acids bound and polymer content are two independent variables that can affect the performance of an albumin as a hemagglutination enhancer.

Drug Synergism↗
PubMed1995

Virucidal effects of the steam distillate from Houttuynia cordata and its components on HSV-1, influenza virus, and HIV.

The steam distillate prepared from fresh plants of Houttuynia cordata Thunb. (Saururaceae) was found to have direct inhibitory activity against herpes simplex virus type 1 (HSV-1), influenza virus, and human immunodeficiency virus type 1 (HIV-1) without showing cytotoxicity, but not against poliovirus and coxsackie-virus. The loss of viral infectivity was related to the duration of drug treatment. Three major components of the distillate, methyl n-nonyl ketone, lauryl aldehyde, and capryl aldehyde, also inactivated HSV-1, influenza virus, and HIV-1. These in vitro findings demonstrate that the essential oils provide virucidal activity against enveloped viruses by interfering with the function of virus envelope.

Animals↗
PubMed2003

Myocardial recovery from ischemia is impaired in CD36-null mice and restored by myocyte CD36 expression or medium-chain fatty acids.

Long-chain fatty acid uptake, which provides a large part of myocardial energy, is impaired in human and murine hearts deficient in the membrane fatty acid translocase, FAT/CD36. We examined myocardial function in CD36-null mice using the working heart. Fatty acid oxidation and stores of glycogen, triglycerides, and ATP were reduced in CD36-deficient hearts and were restored to WT levels by rescue of myocyte CD36. Under normal perfusion conditions, CD36-null hearts had similar cardiac outputs and end-diastolic pressures as WT or transgenic hearts. After 6 min of ischemia, cardiac output decreased by 41% and end diastolic pressure tripled for CD36-null hearts, with no significant changes in WT or transgenic hearts. Null hearts also failed more frequently after ischemia as compared with WT or transgenics. To dissect out contribution of fatty acid uptake, a perfusate-lacking fatty acids was used. This decreased cardiac output after ischemia by 30% in WT hearts as compared with 50% for CD36-deficient hearts. End diastolic pressure, a negative index of myocardial performance, increased after ischemia in all heart types. Addition to the perfusate of a medium-chain fatty acid (caprylic acid) that does not require CD36 for uptake alleviated poor ischemic tolerance of CD36-null hearts. In summary, recovery from ischemia is compromised in CD36-deficient hearts and can be restored by CD36 rescue or by supplying medium-chain fatty acids. It would be important to determine whether the findings apply to the human situation where polymorphisms of the CD36 gene are relatively common.

Animals↗
PubMed2006

Discrimination of esterase and peptidase activities of acylaminoacyl peptidase from hyperthermophilic Aeropyrum pernix K1 by a single mutation.

It has been shown that highly conserved residues that form crucial structural elements of the catalytic apparatus may be used to account for the evolutionary history of enzymes. Using saturation mutagenesis, we investigated the role of a conserved residue (Arg(526)) at the active site of acylaminoacyl peptidase from hyperthermophilic Aeropyrum pernix K1 in substrate discrimination and catalytic mechanism. This enzyme has both peptidase and esterase activities. The esterase activity of the wild-type enzyme with p-nitrophenyl caprylate as substrate is approximately 7 times higher than the peptidase activity with Ac-Leu-p-nitroanilide as substrate. However, with the same substrates, this difference was increased to approximately 150-fold for mutant R526V. A more dramatic effect occurred with mutant R526E, which essentially completely abolished the peptidase activity but decreased the esterase activity only by a factor of 2, leading to a 785-fold difference in the enzyme activities. These results provide rare examples that illustrate how enzymes can be evolved to discriminate their substrates by a single mutation. The possible structural and energetic effects of the mutations on k(cat) and K(m) of the enzyme were discussed based on molecular dynamics simulation studies.

Aeropyrum↗
PubMed2004

The effect of six different C18 fatty acids on body fat and energy metabolism in mice.

We studied the effects of five high-fat semi-purified diets varying at a 4% (w/w) level in either stearic, oleic, linoleic, alpha-linolenic, or gamma-linolenic acid on body fat and energy metabolism in BALB/c mice. A diet containing caprylic, capric, lauric, and myristic acid was used as a reference diet and a diet with 4% conjugated linoleic acid (CLA) was used as a positive control as it is known to effectively lower body fat in mice. The diets were fed for 35 d. Body fat was significantly lower in the CLA group than in the other groups but was not significantly different among the non-CLA groups. Among the non-CLA groups, the linoleic acid group tended to have the highest and the alpha-linolenic acid group the lowest proportion of body fat. In energy-balance studies, the percentage of energy intake that was stored in the body was significantly lower in the CLA group compared with the other dietary groups. The percentage of energy intake eliminated in excreta was highest in the stearic acid group followed by the gamma-linolenic acid group. These results were reflected in apparent fat digestibility, which was lowest in the stearic acid group. The percentage of energy intake expended as heat was highest in the CLA-fed mice. The results of the present study suggest that body fat and energy accretion in mice fed diets containing different C18 fatty acids is by far the lowest with CLA and that linoleic acid produced the highest fat intake and energy accretion.

Adipose Tissue↗
PubMed1999

Fatty acid composition of six varieties of dehulled African yam bean (Sphenostylis stenocarpa) flour.

The proximate and fatty acids compositions of dehulled African yam bean (Sphenostylis stenocarpa, Hochst ex A. Rich. Harms) flour were reported. The crude protein values ranged from 20.18 +/- 0.02 to 25.78 +/- 0.05 g/100 g; the ether extract values ranged from 1.93 +/- 0.05 to 10.18 +/- 0.04 g/100 g; crude fibre values ranged from 1.61 +/- 0.02 to 2.38 +/- 0.00 g/100 g; total ash ranged from 2.06 +/- 0.03 to 2.36 +/- 0.05 g/100 g and carbohydrate values ranged from 58.46 +/- 0.04 to 63.34 +/- 0.05 g/100 g. The values of the moisture content ranged from 3.20 +/- 0.03 to 7.10 +/- 0.02 g/100 g. Significant differences were found (P < 0.05) among the samples in the proximate compositions. The most concentrated fatty acids were palmitic acid (18.18 to 19.78%) < linoleic acid (28.33 to 35.16%) < stearic acid (29.01 to 36.71%). Caprylic, capric, lauric, myristic, palmitoleic, oleic, eicosenoic and erucic acids were present in small quantities with none of them recording up to 2.00% in any of the samples. However, the values of alpha-linolenic acid ranged from 2.01 to 2.96%. Significant differences were observed in the fatty acid compositions among the African yam bean dehulled seed cultivars.

Flour↗
PubMed1989

Cuphea: a new plant source of medium-chain fatty acids.

The plant genus Cuphea (family Lythraceae) promises to provide a new source of industrially and nutritionally important medium-chain fatty acids, especially of lauric acid now supplied exclusively by coconut and palm kernel oils from foreign sources. The seed lipids of Cuphea were first discovered in the 1960s to contain high percentages of several medium-chain fatty acids, including caprylic, capric, lauric, and myristic acid. Research is still in the early stages, but it is intensifying toward the goal of developing the genus into a new temperate climate crop for production of specialty oils. Given the diversity of Cuphea seed lipid composition and the wide ecological and distributional range of the genus, it may be possible to tailor crops to produce selected fatty acids on demand under a variety of growing conditions. Cuphea comprises about 260 species, most native to the New World tropics. Its morphology, classification, chromosome numbers, distribution, ecology, and folk uses are presented. Seed structure is described and seed lipid composition for 73 species is summarized. Problems in domestication and agronomic progress are reviewed. Knowledge of the biosynthetic mechanism controlling the lipids produced by Cuphea remains very limited. Future research in this area, and particularly successful employment of gene transfer techniques, may allow genes controlling the mechanism to be transferred to an already established seed oil producer such as rapeseed. Presently, both traditional plant breeding techniques and newer biotechnological methods are directed toward Cuphea oilseed development.

Fatty Acids↗
PubMed1991

Generation of monoclonal antibodies to bovine follicle-stimulating hormone and application in an enzyme immunoassay.

Twenty monoclonal antibodies (MAbs) to bovine follicle-stimulating hormone (bFSH) were generated by using the hybridoma technique. Twelve of the MAbs have been shown to bind specifically to bFSH and seven of them were purified from the respective ascitic fluids with the methods of caprylic acid precipitation and hydroxylapatite column chromatography. The purity of the MAbs was in the range of 86-95%. Three of the purified MAbs have been coupled to horseradish peroxidase (HRP). By using a matrix cross-matching procedure, two MAbs reacted with discrete antigenic determinants are selected for a double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA). The designed ELISA procedure could be performed within 60 min in a two-stage incubation and has a minimum sensitivity of 1ngFSH/ml. For serum samples, its mean intra- and inter-assay coefficients of variation were 3.4% and 7.3% respectively. The DAS-ELISA can be used to establish a complete FSH profile in the field of in vitro diagnosis.

Animals↗
PubMed1996

Production and characterization of the monoclonal antibody against SGP120, a novel serum protein.

A monoclonal antibody designated B1.9.E-2 was produced and characterized to facilitate study of the immunizing antigen-a serum glycoprotein of 120 kDa (sgp 120) of unknown function. The antibody, produced in mice, reacts with 1-2 epitopes located in the N-terminal region of the sgp 120 molecule. The affinity of the reaction, as determined by Scatchard analysis, is Ka = 1.13 x 10(10) I/M and is of a hydrophobic nature. The monoclonal antibody can be purified to a high degree by a modified caprylic acid method and by protein G FPLC chromatography column. B1.9.E-2 does not trigger the complement cascade, as determined by C3 RIA and immune complex solubilization assays. Both affinity purified (C4b Sepharose) and chromatographically isolated (using jacqualine agarose) sgp 120 were recognized by B1.9.E-2. The monoclonal antibody can be utilized for affinity purification of sgp 120, for detection of intact or cleaved sgp 120 in biological samples of healthy and ill individuals, and for the number of functional and neutralization assays aimed at resolving the physiologic role of sgp 120.

Amino Acid Sequence↗
PubMed1997

Dietary fat saturation effects on low-density-lipoprotein concentrations and metabolism in various animal models.

Saturated vegetable oils (coconut, palm, and palm kernel oil) and fats (butter and lard) are hypercholesterolemic relative to monounsaturated and polyunsaturated vegetable oils. The increase in plasma low-density-lipoprotein-cholesterol (LDL-C) concentrations associated with consumption of saturated vegetable oils and fats is largely explained by a decrease in hepatic LDL receptor activity and an increase in the LDL-C production rate. Hepatic LDL receptor activity may be regulated by the messenger RNA concentration of the LDL receptor. The decrease in hepatic LDL receptor activity with saturated fat feeding is associated with decreased hepatic sterol O-acyltransferase activity and, therefore, a reduced inert pool of cholesteryl ester. A putative regulatory pool of cholesterol is increased with saturated fat feeding and suppresses LDL receptor activity, possibly through hepatic messenger RNA regulation. For most studies, an independent effect of a vegetable oil or fat could not be ascertained because there was no neutral control and at least two of the test oils or fats were varied. Animal data for the effects of individual fatty acids on plasma LDL-C concentrations and metabolism are sparse. The evidence suggests that caproic acid (6:0), caprylic acid (8:0), and capric acid (10:0) are neutral with respect to their LDL-C-raising properties and their ability to modulate LDL metabolism. Lauric acid (12:0), myristic acid (14:0), and palmitic acid (16:0) are approximately equivalent in their LDL-C-raising potential by reducing hepatic LDL receptor activity and increasing the LDL-C production rate, apparently via modulation of sterol O-acyltransferase activity. Stearic acid (18:0) appears to be neutral in its LDL-C-raising potential and how it affects LDL metabolism.

Animals↗
PubMed2005

Transcriptome and proteome analysis identifies the pathways that increase hepatic lipid accumulation in zinc-deficient rats.

For identification of the underlying molecular changes in hepatic lipid metabolism in zinc deficiency, rats were force-fed a zinc-deficient diet. Subsequently DNA-microarray and proteome profiling was performed in combination with hepatic lipid analysis. Of 6200 target sequences analyzed, 268 transcripts showed altered expression levels in livers of zinc-deficient rats, with 43 genes thereof related to hepatic lipid metabolism. Northern blot analysis and quantitative real-time RT-PCR were employed to confirm changes in mRNA levels. Proteins involved in lipid metabolism were identified by proteome analysis. Functional gene clusters with uniform changes in transcript levels suggested that the pathways required for lipolysis and mitochondrial as well as peroxisomal fatty acid degradation were downregulated, whereas those needed for de novo fatty acid synthesis and triglyceride assembly were increased. Subsequent enzymatic analysis of liver tissues confirmed an almost 40% greater triacylglycerol concentration in zinc-depleted rats, as well as an altered fatty acid composition of the lipid fraction as determined by gas chromatography. Liver lipids of zinc-deficient rats had significantly greater proportions of cis-9-oleic acid, cis-11-vaccenic acid, caprylic acid, myristic acid, alpha-linolenic acid, and eicosapentaenoic acid, and significantly less stearic and arachidonic acids. These alterations in hepatic metabolism are discussed in the context of changes in mRNA and protein levels of enzymes and transporters responsible for fatty acid metabolism, sequestration, and their transcriptional control.

Animals↗
PubMed2002

Modifying the chain-length selectivity of the lipase from Burkholderia cepacia KWI-56 through in vitro combinatorial mutagenesis in the substrate-binding site.

The mature lipase of Burkholderia cepacia KWI-56 was synthesized in an enzymatically active form using an in vitro Escherichia coli S30 coupled transcription/translation system by expressing the mature lipase gene (rlip) in the presence of its specific activator. To investigate the substrate specificity of the lipase comprehensively, a large number of mutant lipases were constructed and analyzed in a high throughput manner by combining overlapping PCR and in vitro protein synthesis. In this paper, Phe119 and Leu167, which are located in the acyl portion of the substrate-binding pocket of the lipase of B.cepacia KWI-56, were substituted with six hydrophobic amino acid residues by the in vitro combinatorial mutagenesis. The wild-type and 35 mutant genes amplified by PCR were directly used as templates for the in vitro transcription/translation. The acyl chain-length selectivity of the in vitro expressed lipases against p-nitrophenyl butyrate, p-nitrophenyl caprylate and p-nitrophenyl palmitate, was compared by their relative hydrolysis rates. Two mutant lipases, L167V and F119A/L167M, which showed a significant shift in substrate selectivity were further expressed in vivo and refolded in vitro. It was found that L167V raised its preference for the short-chain ester, whereas F119A/L167M improved its selectivity for the long-chain ester.

Binding Sites↗
PubMed1981

Metabolism of normal and ischemically injured rabbit kidneys during perfusion for 48 hours at 10 C.

We report a study of the effects of perfusate composition on the 5'-adenine nucleotides of rabbit kidneys perfused continuously at 10 C for 24 or 48 hr. It was found that when glucose was the sole energy source and the pO2 was approximately 150 mm Hg, the total high-energy phosphate content was reduced to one-half and total adenine nucleotides to one-third after 48-hr perfusion of freshly isolated kidneys. At this pO2 the supplementation of glucose of additional energy substrates had no effect on adenine nucleotide reserves, but the inclusion of hypoxanthine did have a positive effect, although not sufficient to restore normal levels. Increasing the pO2 to approximately 650 mm Hg however, in combination with the provision of energy substrates and hypoxanthine, produced adenine nucleotide levels very close to normal after 48 hr of perfusion. Study of metabolites in the perfusate suggested that significant glycolysis occurred when the pO2 was 150 mm Hg: it was stimulated by caprylate and inhibited by raising the pO2 to 650 mm Hg. Kidneys exposed to 60 min of warm ischemia before perfusion had severely depleted adenine nucleotide levels (less than one-fifth of normal) but after 48-hr perfusion with hypoxanthine, energy substrates, and a high pO2, the total adenine nucleotides were restored to normal and only the ATP to ADP ratio was significantly less than that observed in kidneys perfused for 48 hr without prior warm ischemia. Study of metabolites in the perfusate suggested that a burst of aerobic respiration occurred after a lag period of 20 hr in these kidneys. It is clear that a remarkable recovery of adenine nucleotides can occur during perfusion, under appropriate conditions, of kidneys damaged by warm ischemia.

Adenosine Diphosphate↗
PubMed1989

Haemolysins and extracellular enzymes of Listeria monocytogenes and L. ivanovii.

Of 120 laboratory-maintained strains of Listeria monocytogenes and two of L. ivanovii examined for haemolytic and lipolytic activity, 62 exhibited haemolytic activity alone, 20 of these showed haemolytic and lipolytic activity and 40 had neither activity. The L. ivanovii strains showed both activities. The results indicated a relationship between haemolysin production and lipolytic activity which was not explained by the serotype of the organism. In addition, the following hydrolytic activities were detected in the cell-free growth media of strains L. monocytogenes Boldy and L. ivanovii (formerly L. monocytogenes) Type 5 (substrates acted upon are given in parentheses): acid phosphate (4-nitrophenylphosphate, naphthyl phosphate, glycerophosphate, phosphorylcholine and GTP); neutral phosphatase (4-nitrophenylphosphate, naphthyl phosphate, phosphorylcholine, NADP and UDPG); phosphodiesterase (bis-4-nitrophenylphosphate, ATP and NADP); NADase (NAD); phospholipase C (4-nitrophenylphosphoryl-choline, phosphatidyl choline and ethanolamine, and sphingomyelin); and lipase and esterase (triacetin, tributyrin, triolein, naphthyl-laurate,-myristate,-caprylate,-palmitate and -oleate, 4-nitrophenyl-acetate-laurate and Tween 80). The preparations also showed weak catalase activity. No evidence was found for the presence of RNAase, DNAase, peptidase/amidase, phosphoamidase, alpha-amylase, glucosidase, galactosidase, pyranosidase or glucose aminidase.

Culture Media↗
PubMed1990

Detection of diphtheria toxin in culture supernates of Corynebacterium diphtheriae and C. ulcerans by immunoassay with monoclonal antibody.

Monoclonal antibody (MAb) to diphtheria toxin was produced in mouse hybridomas, and shown by ELISA to be of sub-class IgG1. Hybridomas were inoculated into mice to produce ascitic fluid from which MAb was purified by caprylic acid. The MAb was shown by immunoblotting to be directed against the A fragment of the toxin and also against the intact toxin molecule. After conjugation with fluorescein isothiocyanate, it was used in an immunoassay to detect toxin in culture supernates of Corynebacterium diphtheriae and C. ulcerans. The assay correlated well with the Elek test and with virulence in guinea-pigs; but it gave occasional false positive results, probably by binding of MAb to defective toxin.

Animals↗
PubMed2005

The pimFABCDE operon from Rhodopseudomonas palustris mediates dicarboxylic acid degradation and participates in anaerobic benzoate degradation.

Bacteria in anoxic environments typically convert aromatic compounds derived from pollutants or green plants to benzoyl-CoA, and then to the C7 dicarboxylic acid derivative 3-hydroxypimelyl-CoA. Inspection of the recently completed genome sequence of the purple nonsulfur phototroph Rhodopseudomonas palustris revealed one predicted cluster of genes for the beta-oxidation of dicarboxylic acids. These genes, annotated as pimFABCDE, are predicted to encode acyl-CoA ligase, enoyl-CoA hydratase, acyl-CoA dehydrogenase and acyl-CoA transferase enzymes, which should allow the conversion of odd-chain dicarboxylic acids to glutaryl-CoA, and even-chain dicarboxylic acids to succinyl-CoA. A mutant strain that was deleted in the pim gene cluster grew at about half the rate of the wild-type parent when benzoate or pimelate was supplied as the sole carbon source. The mutant grew five times more slowly than the wild-type on the C14 dicarboxylic acid tetradecanedioate. The mutant was unimpaired in growth on the C8-fatty acid caprylate. The acyl-CoA ligase predicted to be encoded by the pimA gene was purified, and found to be active with C7-C14 dicarboxylic and fatty acids. The expression of a pimA-lacZ chromosomal gene fusion increased twofold when cells were grown in the presence of straight-chain C7-C14 dicarboxylic and fatty acids. These results suggest that the beta-oxidation enzymes encoded by the pim gene cluster are active with medium-chain-length dicarboxylic acids, including pimelate. However, the finding that the pim operon deletion mutant is still able to grow on dicarboxylic acids, albeit at a slower rate, indicates that R. palustris has additional genes that can also specify the degradation of these compounds.

Anaerobiosis↗
PubMed1980

Fatty acid patterns during plasma fractionation.

When albumin is prepared from human blood plasma by the cold ethanol method, nonesterified long chain fatty acids present in the plasma do not strictly copurify with albumin. About half of them are lost to the varioius globulin fractions precipitated in the first steps of the fractionation procedure. A different behavior is observed for the short chain fatty acid, caprylic acid. On the other hand, if fractionation of plasma proteins is done by ammonium sulfate precipitation, both long and short chain fatty acids remain with the albumin.

Ammonium Sulfate↗
PubMed1984

Thermal stability of human albumin measured by differential scanning calorimetry. II. Effects of isomers of N-acetyltryptophanate and tryptophanate, pH, reheating, and dimerization.

Thermal stability of undefatted human albumin preparations at 5% concentration and neutral pH in 145 mM Na+ was investigated by differential scanning calorimetry. At 30 and 4 mM N-acetyltryptophanate, the thermogram for previously unheated albumin monomer is independent of the stereochemistry of this ligand; thus, the affinity of the protein must be the same for the L- and D-isomers in the temperature range of thermal denaturation (62-86 degrees C). 26 mM L-tryptophanate bestows a slight increase in stability on previously unheated monomer, whereas 27 mM D-tryptophanate has no effect, a result consistent with the reported weaker binding of the D-isomer. Previously unheated albumin monomer shows slightly greater thermal stability at pH 6.4 than at pH 7.4. The tracing of differential heat capacity versus temperature (thermogram) for monomer from once heated albumin, i.e. once processed and once heated normal serum albumin (NSA), is almost identical to that for previously unheated monomer. Monomer prepared from outdated, multiply reprocessed, multiply reheated NSA (old monomer) had the same corresponding denaturation temperatures as previously unheated monomer; the corresponding dimer (old dimer) is slightly less stable. Thermograms for old monomer and old dimer, like those for previously unheated monomer, comprise two denaturation peaks (endotherms). Their endotherms, however, are very broad, reflecting the great heterogeneity of the old proteins. The thermogram for old monomer remains broad even in the presence of N-acetyltryptophanate and/or caprylate. Old dimer does not dissociate when undergoing thermal denaturation.

Calorimetry, Differential Scanning↗