Sample records for acid composition dipeptide

  1. Dipeptide Sequence Determination: Analyzing Phenylthiohydantoin Amino Acids by HPLC

    NASA Astrophysics Data System (ADS)

    Barton, Janice S.; Tang, Chung-Fei; Reed, Steven S.

    2000-02-01

    Amino acid composition and sequence determination, important techniques for characterizing peptides and proteins, are essential for predicting conformation and studying sequence alignment. This experiment presents improved, fundamental methods of sequence analysis for an upper-division biochemistry laboratory. Working in pairs, students use the Edman reagent to prepare phenylthiohydantoin derivatives of amino acids for determination of the sequence of an unknown dipeptide. With a single HPLC technique, students identify both the N-terminal amino acid and the composition of the dipeptide. This method yields good precision of retention times and allows use of a broad range of amino acids as components of the dipeptide. Students learn fundamental principles and techniques of sequence analysis and HPLC.

  2. Density functional theory calculations on dipeptide gallic acid interaction

    NASA Astrophysics Data System (ADS)

    Madhan, B.; Parthasarathi, R.; Subramanian, V.; Raghava Rao, J.; Nair, Balachandran Unni; Ramasami, T.

    2003-02-01

    In the present investigation, an attempt has been made to study the interaction of dipeptides with gallic acid, using Becke3 parameter Lee Yang Parr (B3LYP) method employing 3-21G*, 6-31G* and 6-31+G* basis sets. The interaction energies of the dipeptide-gallic acid complexes are in the range of -5 to -18 kcal/mol depending on the mode of intermolecular complexation. Calculated molecular electrostatic potential (MESP) for the various intermolecular complexes revealed the electrostatic nature of the interaction. Qualitative estimations based on chemical hardness and chemical potential demonstrated fractional electron transfer from dipeptide to gallic acid.

  3. Density functional theory calculations on dipeptide–gallic acid interaction

    Microsoft Academic Search

    B. Madhan; R Parthasarathi; V Subramanian; J Raghava Rao; Balachandran Unni Nair; T Ramasami

    2003-01-01

    In the present investigation, an attempt has been made to study the interaction of dipeptides with gallic acid, using Becke3 parameter Lee Yang Parr (B3LYP) method employing 3-21G*, 6-31G* and 6-31+G* basis sets. The interaction energies of the dipeptide–gallic acid complexes are in the range of ?5 to ?18 kcal\\/mol depending on the mode of intermolecular complexation. Calculated molecular electrostatic

  4. iHyd-PseAAC: Predicting Hydroxyproline and Hydroxylysine in Proteins by Incorporating Dipeptide Position-Specific Propensity into Pseudo Amino Acid Composition

    PubMed Central

    Xu, Yan; Wen, Xin; Shao, Xiao-Jian; Deng, Nai-Yang; Chou, Kuo-Chen

    2014-01-01

    Post-translational modifications (PTMs) play crucial roles in various cell functions and biological processes. Protein hydroxylation is one type of PTM that usually occurs at the sites of proline and lysine. Given an uncharacterized protein sequence, which site of its Pro (or Lys) can be hydroxylated and which site cannot? This is a challenging problem, not only for in-depth understanding of the hydroxylation mechanism, but also for drug development, because protein hydroxylation is closely relevant to major diseases, such as stomach and lung cancers. With the avalanche of protein sequences generated in the post-genomic age, it is highly desired to develop computational methods to address this problem. In view of this, a new predictor called “iHyd-PseAAC” (identify hydroxylation by pseudo amino acid composition) was proposed by incorporating the dipeptide position-specific propensity into the general form of pseudo amino acid composition. It was demonstrated by rigorous cross-validation tests on stringent benchmark datasets that the new predictor is quite promising and may become a useful high throughput tool in this area. A user-friendly web-server for iHyd-PseAAC is accessible at http://app.aporc.org/iHyd-PseAAC/. Furthermore, for the convenience of the majority of experimental scientists, a step-by-step guide on how to use the web-server is given. Users can easily obtain their desired results by following these steps without the need of understanding the complicated mathematical equations presented in this paper just for its integrity. PMID:24857907

  5. Effect of Dipeptides on the Growth of Oenococcus oeni in Synthetic Medium Deprived of Amino Acids

    Microsoft Academic Search

    Pedro A. Aredes Fernández; Fabiana M. Saguir; María C. Manca de Nadra

    2004-01-01

    Oenococcus oeni has numerous amino acid requirements for growth and dipeptides could be important for its nutrition. In this paper the individual or combined effect of dipeptides on growth of O. oeni X 2L in synthetic media deficient in one or more amino acids with L-malic acid was investigated. Utilization of dipeptides, glucose, and L-malic acid was also analyzed. Dipeptides

  6. Kinetic studies of dipeptide-based and amino acid-based peritoneal dialysis solutions

    Microsoft Academic Search

    Andrzej Wery?ski; Jacek Waniewski; Tao Wang; Björn Anderstam; Bengt Lindholm; Jonas Bergström

    2001-01-01

    Kinetic studies of dipeptide-based and amino acid-based peritoneal dialysis solutions.BackgroundDipeptide-based peritoneal dialysis solutions may have potential advantages compared with the glucose or amino acid-based solutions. Dipeptides may hydrolyze in the peritoneal cavity, generating constituent amino acids and thereby increasing the osmolality of the dialysate. Dipeptides can also be a valuable source of amino acids, which are poorly soluble in water,

  7. Structure property relationships of amino acids and some dipeptides

    Microsoft Academic Search

    L. Pogliani

    1994-01-01

    A molecular connectivity model of the crystal densities and specific rotations of some natural amino acids and of the longitudinal relaxation rates of some natural amino acids and cyclic dipeptides is presented. While crystal densities and relaxation rates are better described by a set of three valence molecular connectivity indices {Dv,0Xv,1Xv}, specific rotations are better described by a set of

  8. Synthesis and antiproliferative activity of glutamic acid-based dipeptides.

    PubMed

    Silveira-Dorta, Gastón; Martín, Víctor S; Padrón, José M

    2015-08-01

    A small and focused library of 22 dipeptides derived from N,N-dibenzylglutamic acid ?- and ?-benzyl esters was prepared in a straightforward manner. The evaluation of the antiproliferative activity in the human solid tumor cell lines HBL-100 (breast), HeLa (cervix), SW1573 (non-small cell lung), T-47D (breast), and WiDr (colon) provided ?-glutamyl methionine (GI50 = 6.0-41 ?M) and ?-glutamyl proline (GI50 = 7.5-18 ?M) as lead compounds. In particular, glutamyl serine and glutamyl proline dipeptides were more active in the resistant cancer cell line WiDr than the conventional anticancer drugs cisplatin and etoposide. Glutamyl tryptophan dipeptides did not affect cell growth of HBL-100, while in T-47D cells, proliferation was inhibited. This result might be attributed to the inhibition of the ATB(0,+) transporter. PMID:25900811

  9. The effect of amino acids and dipeptides on sodium and water absorption in man

    Microsoft Academic Search

    M. D. Hellier; C. Thirumalai; C. D. Holdsworth

    1973-01-01

    A perfusion technique has been used to quantitate the effect of the amino acids glycine and alanine and the dipeptides glycyl-glycine and glycyl-L-alanine on sodium and water absorption from the human jejunum. Although no net absorption of sodium and water was seen in the absence of non-electrolytes, a significant stimulation occurred in the presence of both free amino acids and

  10. N-( p-Ethynylbenzoyl) derivatives of amino acid and dipeptide methyl esters - Synthesis and structural study

    NASA Astrophysics Data System (ADS)

    Eißmann, Frank; Weber, Edwin

    2011-11-01

    A series of N-( p-ethynylbenzoyl) derivatives ( 1-4) of the amino acids glycine and L-alanine as well as the dipeptides glycylglycine and L-alanylglycine has been synthesized via a two-step reaction sequence including the reaction of an appropriate N-( p-bromobenzoyl) precursor with trimethylsilylacetylene followed by deprotection of the trimethylsilyl protecting group, respectively. X-ray crystal structures of the amino acid and dipeptide methyl esters 1-4 are reported. The amide and peptide bonds within each molecular structure are planar and adopt the trans-configuration. The packing structures are governed by N sbnd H⋯O interactions leading to the formation of characteristic strand motifs. Further stabilization results from weaker C sbnd H⋯O and C sbnd H⋯? contacts.

  11. Free amino acid and dipeptide changes in the body fluids from Alzheimer’s disease subjects

    Microsoft Academic Search

    A. N. Fonteh; R. J. Harrington; A. Tsai; P. Liao; M. G. Harrington

    2007-01-01

    Summary.  Our aim was to determine changes in free amino acid (FAA) and dipeptide (DP) concentrations in probable Alzheimer’s disease\\u000a (pAD) subjects compared with control (CT) subjects using liquid chromatography and electrospray ionization tandem mass spectrometry\\u000a (LCMS2). We recruited gender- and age-matched study participants based on neurological and neuropsychological assessments. We measured\\u000a FAAs and DPs in cerebrospinal fluid (CSF), plasma and

  12. Synthesis of functional dipeptide carnosine from nonprotected amino acids using carnosinase-displaying yeast cells

    Microsoft Academic Search

    Chiaki Inaba; Shinsuke Higuchi; Hironobu Morisaka; Kouichi Kuroda; Mitsuyoshi Ueda

    2010-01-01

    Carnosine (?-alanyl-l-histidine) is one of the bioactive dipeptides and has antioxidant, antiglycation, and cytoplasmic buffering properties. In\\u000a this study, to synthesize carnosine from nonprotected amino acids as substrates, we cloned the carnosinase (CN1) gene and\\u000a constructed a whole-cell biocatalyst displaying CN1 on the yeast cell surface with ?-agglutinin as the anchor protein. The\\u000a display of CN1 was confirmed by immunofluorescent

  13. Synthesis and conformational analysis of hybrid ?/?-dipeptides incorporating S-glycosyl-?(2,2)-amino acids.

    PubMed

    García-González, Iván; Mata, Lara; Corzana, Francisco; Jiménez-Osés, Gonzalo; Avenoza, Alberto; Busto, Jesús H; Peregrina, Jesús M

    2015-01-12

    We synthesized and carried out the conformational analysis of several hybrid dipeptides consisting of an ?-amino acid attached to a quaternary glyco-?-amino acid. In particular, we combined a S-glycosylated ?(2,2)-amino acid and two different types of ?-amino acid, namely, aliphatic (alanine) and aromatic (phenylalanine and tryptophan) in the sequence of hybrid ?/?-dipeptides. The key step in the synthesis involved the ring-opening reaction of a chiral cyclic sulfamidate, inserted in the peptidic sequence, with a sulfur-containing nucleophile by using 1-thio-?-D-glucopyranose derivatives. This reaction of glycosylation occurred with inversion of configuration at the quaternary center. The conformational behavior in aqueous solution of the peptide backbone and the glycosidic linkage for all synthesized hybrid glycopeptides was analyzed by using a protocol that combined NMR experiments and molecular dynamics with time-averaged restraints (MD-tar). Interestingly, the presence of the sulfur heteroatom at the quaternary center of the ?-amino acid induced ? torsional angles close to 180° (anti). Notably, this value changed to 60° (gauche) when the peptidic sequence displayed aromatic ?-amino acids due to the presence of CH-? interactions between the phenyl or indole ring and the methyl groups of the ?-amino acid unit. PMID:25413453

  14. A concept of dietary dipeptides: a step to resolve the problem of amino acid availability in the early life of vertebrates

    Microsoft Academic Search

    Konrad Dabrowski; Bendik F. Terjesen; Yongfang Zhang; James M. Phang; Kyeong-Jun Lee

    2005-01-01

    The premise that a dietary dipeptide approach will improve the understanding of amino acid utilization in the fastest-growing vertebrate, the teleost fish, was tested by examining the muscle free amino acid (FAA) pool and enzyme activities, in concert with growth response, when dietary amino acids were provided in free, dipeptide or protein molecular forms. We present the first evidence in

  15. Lipoteichoic acid and muramyl dipeptide synergistically induce maturation of human dendritic cells and concurrent expression of proinflammatory cytokines

    Microsoft Academic Search

    Hye Jin Kim; Jae Seung Yang; Sang Su Woo; Sun Kyung Kim; Cheol-Heui Yun; Kack Kyun Kim; Seung Hyun Han

    2007-01-01

    Maturation is an important process by which dendritic cells (DC) develop the potent anti- gen-presentation capacity necessary for efficient activation of adaptive immunity. Here, we have investigated the ability of lipoteichoic acid (LTA) and muramyl dipeptide (MDP; the minimal struc- tural unit of peptidoglycan with immunostimulating activity) to induce maturation of human immature DC (iDC), derived from peripheral blood CD14-

  16. Dipeptide Formation from Amino Acid Monomer Induced by keV Ion Irradiation: An Implication for Physicochemical Repair by Radiation Itself

    NASA Astrophysics Data System (ADS)

    Wang, Wei; Yuan, Hang; Wang, Xiangqin; Yu, Zengliang

    2008-02-01

    An identification of Phe dipeptide from L-phenylalanine monomers after keV nitrogen and argon ion implantation, by using the HPLC (high performance liquid chromatography) and LC-MS(liquid chromatography mass spectrometer) methods is reported. The results showed a similar yield behavior for both ion species, namely: 1) the yield of dipeptides under alkalescent conditions was distinctly higher than that under acidic or neutral conditions; 2) for different ion species, the dose-yield curves tracked a similar trend which was called a counter-saddle curve. The dipeptide formation may implicate a recombination repair mechanism of damaged biomolecules that energetic ions have left in their wake. Accordingly a physicochemical self-repair mechanism by radiation itself for the ion-beam radiobiological effects is proposed.

  17. Enantioseparation of dansyl amino acids and dipeptides by chiral ligand exchange capillary electrophoresis based on Zn(II)-L-hydroxyproline complexes coordinating with ?-cyclodextrins.

    PubMed

    Mu, Xiaoyu; Qi, Li; Qiao, Juan; Yang, Xinzheng; Ma, Huimin

    2014-10-10

    A chiral ligand exchange capillary electrophoresis (CLE-CE) method using Zn(II) as the central ion and L-4-hydroxyproline as the chiral ligand coordinating with ?-cyclodextrin (?-CD) was developed for the enantioseparation of amino acids (AAs) and dipeptides. The effects of various separation parameters, including the pH of the running buffer, the ratio of Zn(II) to L-4-hydroxyproline, the concentration of complexes and cyclodextrins (CDs) were systematically investigated. After optimization, it has been found that eight pairs of labeled AAs and six pairs of labeled dipeptides could be baseline-separated with a running electrolyte of 100.0mM boric acid, 5.0mM ammonium acetate, 3.0mM Zn(II), 6.0mM L-hydroxyproline and 4.0mM ?-CD at pH 8.2. The quantitation of AAs and dipeptides was conducted and good linearity (r(2)?0.997) and favorable repeatability (RSD?3.6%) were obtained. Furthermore, the proposed method was applied in determining the enantiomeric purity of AAs and dipeptides. Meanwhile, the possible enantiorecognition mechanism based on the synergistic effect of chiral metal complexes and ?-CD was explored and discussed briefly. PMID:25220143

  18. Synthesis and application of dipeptides; current status and perspectives

    Microsoft Academic Search

    Makoto Yagasaki; Shin-ichi Hashimoto

    2008-01-01

    The functions and applications of l-?-dipeptides (dipeptides) have been poorly studied compared with proteins or amino acids. Only a few dipeptides, such as\\u000a aspartame (l-aspartyl-l-phenylalanine methyl ester) and l-alanyl-l-glutamine (Ala-Gln), are commercially used. This can be attributed to the lack of an efficient process for dipeptide production\\u000a though various chemical or chemoenzymatic method have been reported. Recently, however, novel methods

  19. Sequence-specific DNA cleavage by dipeptides disubstituted with chlorambucil and 2,6-dimethoxyhydroquinone-3-mercaptoacetic acid.

    PubMed

    Minnock, A; Lin, L S; Morgan, J; Crow, S D; Waring, M J; Sheh, L

    2001-01-01

    Two dipeptides, each containing a lysyl residue, were disubstituted with chlorambucil (CLB) and 2,6-dimethoxyhydroquinone-3-mercaptoacetic acid (DMQ-MA): DMQ-MA-Lys(CLB)-Gly-NH2 (DM-KCG) and DMQ-MA-beta-Ala-Lys(CLB)-NH2 (DM-BKC). These peptide-drug conjugates were designed to investigate sequence-specificity of DNA cleavage directed by the proximity effect of the DNA cleavage chromophore (DMQ-MA) situated close to the alkylating agent (CLB) inside a dipeptide moiety. Agarose electrophoresis studies showed that DM-KCG and DM-BKC possess significant DNA nicking activity toward supercoiled DNA whereas CLB and its dipeptide conjugate Boc-Lys(CLB)-Gly-NH2 display little DNA nicking activity. ESR studies of DMQ-MA and DM-KCG both showed five hyperfine signals centered at g = 2.0052 and are assigned to four radical forms at equilibrium, which may give rise to a semiquinone radical responsible for DNA cleavage. Thermal cleavage studies at 90 degrees C on a 265-mer test DNA fragment showed that besides alkylation and cleavage at G residues, reactions with DM-KCG and DM-BKC show a preference for A residues with the sequence pattern: 5'-G-(A)n-Pur-3' > 5'-Pyr-(A)n-Pyr-3' (where n = 2-4). By contrast, DNA alkylation and cleavage by CLB occurs at most G and A residues with less sequence selectivity than seen with DM-KCG and DM-BKC. Thermal cleavage studies using N7-deazaG and N7-deazaA-substituted DNA showed that strong alkylation and cleavage at A residues by DM-KCG and DM-BKC is usually flanked on the 3' side by a G residue whereas strong cleavage at G residues is flanked by at least one purine residue on either the 5' or 3' side. At 65 degrees C, it is notable that the preferred DNA cleavage by DM-KCG and DM-BKC at A residues is significantly more marked than for G residues in the 265-mer DNA; the strongest sites of A-specific reaction occur within the sequences 5'-Pyr-(A)n-Pyr-3'; 5'-Pur-(A)n-G-3' and 5'-Pyr-(A)n-G-3'. In pG4 DNA, cleavage by DM-KCG and DM-BKC is much greater than that by CLB at room temperature and at 65 degrees C. It was also observed that DM-KCG and DM-BKC cleaved at certain pyrimidine residues: C40, T66, C32, T34, and C36. These cleavages were also sequence selective since the susceptible pyrimidine residues were flanked by two purine residues on both the 5' and 3' sides or by a guanine residue on the 5' side. These findings strongly support the proposal that once the drug molecule is positioned so as to permit alkylation by the CLB moiety, the DMQ-MA moiety is held close to the alkylation site, resulting in markedly enhanced sequence-specific cleavage. PMID:11716676

  20. Microscale Synthesis and Analysis of a Dipeptide.

    ERIC Educational Resources Information Center

    Blatchly, Richard A.; And Others

    1989-01-01

    Described is a microscale chemistry laboratory in which a dipeptide is synthesized from its component amino acids and analyzed using chiral-phase thin-layer chromatography. Experimental procedures, and materials are discussed. Twelve references are listed. (CW)

  1. Highly purified lipoteichoic acid induced pro-inflammatory signalling in primary culture of rat microglia through Toll-like receptor 2: selective potentiation of nitric oxide production by muramyl dipeptide

    Microsoft Academic Search

    Agnieszka Kinsner; Monica Boveri; Lars Hareng; Guy C. Brown; Sandra Coecke; Thomas Hartung; Anna Bal-Price

    2006-01-01

    In contrast to the role of lipopolysaccharide from Gram-neg- ative bacteria, the role of Gram-positive bacterial components in inducing inflammation in the CNS remains controversial. We studied the potency of highly purified lipoteichoic acid and muramyl dipeptide isolated from Staphylococcus aureus to activate primary cultures of rat microglia. Exposure of pure microglial cultures to lipoteichoic acid triggered a significant time-

  2. Micellular Electrokinetic Capillary Chromatography in the Undergraduate Curriculum: Separation and Identification of the Amino Acid Residues in an Unknown Dipeptide Using FMOC Derivatization

    NASA Astrophysics Data System (ADS)

    Strein, Timothy G.; Poechmann, James L.; Prudenti, Mark

    1999-06-01

    This manuscript describes our efforts to introduce biochemistry students to micellar electrokinetic capillary chromatography (MEKC), a mode of capillary electrophoresis that employs micelles in the operating buffer. Unlike free solution capillary electrophoresis, MEKC is capable of resolving both charged and uncharged analytes because the micellar pseudo stationary phase allows for the separation of uncharged species. The experiment described herein includes a comparison of MEKC, employing sodium dodecyl sulfate (SDS) as the micelle-forming species, with reverse-phase HPLC. Both methods are used to determine the amino acid residues in an unknown dipeptide. Advanced undergraduate chemistry, biochemistry, and biology majors perform this experiment in the Biochemical Methods course at Bucknell University. The students cleave the peptide bond, derivatize the resultant amino acids with 9-fluorenylmethyl chloroformate (FMOC), and separate the FMOC-amino acid derivatives using HPLC and MEKC. This manuscript details the analytical procedures for the MEKC separation and presents typical student data obtained using this relatively new method.

  3. Probing gelation ability for a library of dipeptide gelators.

    PubMed

    Awhida, Salmah; Draper, Emily R; McDonald, Tom O; Adams, Dave J

    2015-10-01

    Functionalised dipeptides are a class of interesting and useful low molecular weight hydrogelators. Here, we report a significantly expanded library of materials, including dipeptides conjugated to carbazole, phenanthracene, anthracene, pyrene and substituted naphthalenes. We assess the effect of using two different gelation methods; a pH-switch and a solvent switch on the gelation behaviour and properties of the dipeptides. Importantly, we investigate the relationship between the structure of these dipeptides and their ability to form gels. From an analysis of the gelation ability of all these dipeptides, it is clear that those containing a phenylalanine as either of the constituent amino acids are much more likely to lead to a gelator being formed as opposed to using non-aromatic amino acids only. PMID:26047582

  4. Novel dipeptide nanoparticles for effective curcumin delivery

    PubMed Central

    Alam, Shadab; Panda, Jiban J; Chauhan, Virander S

    2012-01-01

    Background: Curcumin, the principal curcuminoid of the popular Indian spice turmeric, has a wide spectrum of pharmaceutical properties such as antitumor, antioxidant, antiamyloid, and anti-inflammatory activity. However, poor aqueous solubility and low bioavailability of curcumin is a major challenge in its development as a useful drug. To enhance the aqueous solubility and bioavailability of curcumin, attempts have been made to encapsulate it in liposomes, polymeric nanoparticles (NPs), lipid-based NPs, biodegradable microspheres, cyclodextrin, and hydrogels. Methods: In this work, we attempted to entrap curcumin in novel self-assembled dipeptide NPs containing a nonprotein amino acid, ?, ?-dehydrophenylalanine, and investigated the biological activity of dipeptide-curcumin NPs in cancer models both in vitro and in vivo. Results: Of the several dehydrodipeptides tested, methionine-dehydrophenylalanine was the most suitable one for loading and release of curcumin. Loading of curcumin in the dipeptide NPs increased its solubility, improved cellular availability, enhanced its toxicity towards different cancerous cell lines, and enhanced curcumin’s efficacy towards inhibiting tumor growth in Balb/c mice bearing a B6F10 melanoma tumor. Conclusion: These novel, highly biocompatible, and easy to construct dipeptide NPs with a capacity to load and release curcumin in a sustained manner significantly improved curcumin’s cellular uptake without altering its anticancer or other therapeutic properties. Curcumin-dipeptide NPs also showed improved in vitro and in vivo chemotherapeutic efficacy compared to curcumin alone. Such dipeptide-NPs may also improve the delivery of other potent hydrophobic drug molecules that show poor cellular uptake, bioavailability, and efficacy. PMID:22915849

  5. Nucleic acid detection compositions

    SciTech Connect

    Prudent, James R. (Madison, WI); Hall, Jeff G. (Madison, WI); Lyamichev, Victor I. (Madison, WI); Brow, Mary Ann (Madison, WI); Dahlberg, James L. (Madison, WI)

    2008-08-05

    The present invention relates to means for the detection and characterization of nucleic acid sequences, as well as variations in nucleic acid sequences. The present invention also relates to methods for forming a nucleic acid cleavage structure on a target sequence and cleaving the nucleic acid cleavage structure in a site-specific manner. The structure-specific nuclease activity of a variety of enzymes is used to cleave the target-dependent cleavage structure, thereby indicating the presence of specific nucleic acid sequences or specific variations thereof.

  6. Human renin inhibiting dipeptide.

    PubMed

    Toda, N; Miyazaki, M; Etoh, Y; Kubota, T; Iizuka, K

    1986-10-01

    KRI-1177, a dipeptide containing nor-statine inhibited renin activity in human and Japanese monkey plasma to a markedly greater extent than that in dog, rabbit and rat plasma. The systemic blood pressure of anesthetized monkeys was lowered by intravenous injections of this compound which also reduced plasma renin activity and concentration of angiotensins. KRI-1177 appears to selectively inhibit primate renin activity, thereby producing hypotension. PMID:3536533

  7. Discovery of Potent Cysteine-Containing Dipeptide Inhibitors against Tyrosinase: A Comprehensive Investigation of 20 × 20 Dipeptides in Inhibiting Dopachrome Formation.

    PubMed

    Tseng, Tien-Sheng; Tsai, Keng-Chang; Chen, Wang-Chuan; Wang, Yeng-Tseng; Lee, Yu-Ching; Lu, Chung-Kuang; Don, Ming-Jaw; Chang, Chang-Yu; Lee, Ching-Hsiao; Lin, Hui-Hsiung; Hsu, Hung-Ju; Hsiao, Nai-Wan

    2015-07-15

    Tyrosinase is an essential copper-containing enzyme required for melanin synthesis. The overproduction and abnormal accumulation of melanin cause hyperpigmentation and neurodegenerative diseases. Thus, tyrosinase is promising for use in medicine and cosmetics. Our previous study identified a natural product, A5, resembling the structure of the dipeptide WY and apparently inhibiting tyrosinase. Here, we comprehensively estimated the inhibitory capability of 20 × 20 dipeptides against mushroom tyrosinase. We found that cysteine-containing dipeptides, directly blocking the active site of tyrosinase, are highly potent in inhibition; in particular, N-terminal cysteine-containing dipeptides markedly outperform the C-terminal-containing ones. The cysteine-containing dipeptides, CE, CS, CY, and CW, show comparative bioactivities, and tyrosine-containing dipeptides are substrate-like inhibitors. The dipeptide PD attenuates 16.5% melanin content without any significant cytotoxicity. This study reveals the functional role of cysteine residue positional preference and the selectivity of specific amino acids in cysteine-containing dipeptides against tyrosinase, aiding in developing skin-whitening products. PMID:26083974

  8. [Design of the novel dipeptide neuropsychotropic drug preparations].

    PubMed

    Gudasheva, T A; Skoldinov, A P

    2003-01-01

    The paper considers a new strategy in the field of neuropsychotropic dipeptide drug design, the main points being as follows: (i) determination of the structural elements of dipeptides, such as fragments of amino acid side radicals and peptide bonds, in nonpeptide drugs; (ii) design of peptide analogs topologically close to the drug; (iii) synthesis and activity testing of these analogs; (iv) determination of the corresponding endogenous neuropeptide among the known neuropeptides or identification of the new neuropeptides in the brain of experimental animals. Using this approach, new pyroglutamyl- and prolyl-containing dipeptides were obtained based on the structure of the well-known classical nootropic drug piracetam. The new drugs exhibit nootropic activity in doses 100-10,000 times lower than those of piracetam. The structure of most active pyroglutamyl dipeptide pGlu-Asn-NH2 coincides with that of the N-end fragment of the endogenous memory peptide AVP(4-9). Noopept (N-phenylacetylprolylglycine ethyl ester), patented in Russia and USA as a new nootropic drug, is currently under stage 2 of successful clinical trials. The main metabolite of noopept, cyclo-Pro-Gly, is identical to the endogenous dipeptide designed in this work and is most close analog of piracetam with respect to pharmacological activity. The universal character of the proposed strategy is demonstrated by the design of active dipeptide analogs of an atypical neuroleptic drug sulpiride. As a result, a potential dipeptide neuroleptic dilept was obtained, which has been patented in Russia and now passes broad preclinical trials. PMID:12962042

  9. Gelled acidic well treating composition and process

    SciTech Connect

    Swanson, B.L.

    1981-01-13

    Gelled acidic compositions suitable for either matrix-acidizing or fracture-acidizing of subterranean formations comprising water , a water-dispersible polymer selected from cellulose ethers and polymers of acrylamides, an acid, an aldehyde, and a phenolic compound capable of causing gelation of an aqueous dispersion of the polymer, acid, aldehyde, and phenolic compound are provided. In another embodiment, guar gum, polyvinylpyrrolidone and biopolysaccharides can also be used as the polymeric component in said compositions.

  10. Compositions for acid treating subterranean formations

    SciTech Connect

    Clark, E. Jr.; Swanson, B.L.

    1991-03-05

    This patent describes a high viscosity acid composition. It comprises: an aqueous acid solution; one or more acrylamide polymers dissolved in the acid solution in an amount sufficient to increase the viscosity of the acid solution; a liquid hydrocarbon dispersed in the acid solution; and one or more nonionic surface active agents having at least one reactive hydroxyl group per molecule present in the composition in an amount sufficient to interact with the acrylamide polymer or polymers in the presence of the liquid hydrocarbon whereby the viscosity of the acid solution is further increased and stabilized.

  11. Composition for nucleic acid sequencing

    Microsoft Academic Search

    Jonas Korlach; Watt W. Webb; Michael Levene; Stephen Turner; Harold G. Craighead; Mathieu Foquet

    2008-01-01

    The present invention is directed to a method of sequencing a target nucleic acid molecule having a plurality of bases. In its principle, the temporal order of base additions during the polymerization reaction is measured on a molecule of nucleic acid, i.e. the activity of a nucleic acid polymerizing enzyme on the template nucleic acid molecule to be sequenced is

  12. A shape-persistent D,L-dipeptide building block for the assembly of rigidified oligopeptides.

    PubMed

    Hörger, Rolf; Geyer, Armin

    2006-12-21

    Mannuronic acid (5) was transformed into the densely functionalised D,L-dipeptide mimic 1 and subsequently inserted into the cyclic hexapeptide 3. The gulo-configurated seven-membered lactam 1 exhibits an inverted ring conformation compared to the previously described L,L-dipeptide mimic 2. In spite of this considerable difference, both prefer the same i to i + 1 positions of a beta-turn within a cyclic hexapeptide. PMID:17268645

  13. Dipeptide transport and hydrolysis in isolated loops of rat small intestine: effects of stereospecificity.

    PubMed Central

    Lister, N; Sykes, A P; Bailey, P D; Boyd, C A; Bronk, J R

    1995-01-01

    1. Isolated jejunal loops of rat small intestine were perfused by a single pass of bicarbonate Krebs-Ringer solution containing either D- or L-phenylalanine or one of eight dipeptides formed from D- or L-alanine plus D- or L-phenylalanine. 2. At 0.5 mM L-phenylalanyl-L-alanine increased serosal phenylalanine appearance to forty times the control rate giving a value similar to that found with 0.5 mM free L-phenylalanine. No serosal dipeptide could be detected. 3. Perfusions with the two mixed dipeptides with N-terminal D-amino acids (D-alanyl-L-phenylalanine and D-phenylalanyl-L-alanine) gave rise to the appearance of intact dipeptides in the serosal secretions although there were substantial differences in their rates of absorption and subsequent hydrolysis. 4. L-Alanyl-D-phenylalanine was absorbed from the lumen three to five times as fast as L-phenylalanyl-D-alanine. At 1 mM L-alanyl-D-phenylalanine transferred D-phenylalanine across the epithelial layer at more than seven times the rate found with the same concentration of the free D-amino acid. 5. Perfusions with D-alanyl-D-phenylalanine or D-phenylalanyl-D-alanine showed that these two dipeptides are poor substrates for both transport and hydrolysis by the rat small intestine. 6. Analysis of mucosal tissue extracts after perfusion with the two mixed dipeptides with N-terminal D-amino acids revealed that both dipeptides were accumulated within the mucosa and suggested that exit across the basolateral membrane was rate limiting for transepithelial dipeptide transport. Images Figure 5 PMID:7602518

  14. Synthesis and properties of N ? -lauroyl-L-arginine dipeptides from collagen-lauroyl-L-arginine dipeptides from collagen

    Microsoft Academic Search

    J. Molineroa; M. R. Juliao; P. Erraa; M. Roberlb; M. R. Infante

    1988-01-01

    In order to obtain protein-based amphoteric surfactants with antimicrobial properties, N\\u000a ?\\u000a -lauroyl arginine dipeptides have been prepared by condensation between N\\u000a ?\\u000a -lauroyl arginine and amino acids which come from a collagen hydrolysate. Some surfactant properties and the minimum inhibitory\\u000a concentration against Gram positive and Gram negative bacteria have been evaluated. All types of compounds presented a surfactant-like\\u000a behavior.

  15. Lactobacillus plantarum MiLAB 393 Produces the Antifungal Cyclic Dipeptides Cyclo(l-Phe-l-Pro) and Cyclo(l-Phe-trans-4-OH-l-Pro) and 3-Phenyllactic Acid

    PubMed Central

    Ström, Katrin; Sjögren, Jörgen; Broberg, Anders; Schnürer, Johan

    2002-01-01

    We have isolated a Lactobacillus plantarum strain (MiLAB 393) from grass silage that produces broad-spectrum antifungal compounds, active against food- and feed-borne filamentous fungi and yeasts in a dual-culture agar plate assay. Fusarium sporotrichioides and Aspergillus fumigatus were the most sensitive among the molds, and Kluyveromyces marxianus was the most sensitive yeast species. No inhibitory activity could be detected against the mold Penicillium roqueforti or the yeast Zygosaccharomyces bailii. An isolation procedure, employing a microtiter well spore germination bioassay, was devised to isolate active compounds from culture filtrate. Cell-free supernatant was fractionated on a C18 SPE column, and the 95% aqueous acetonitrile fraction was further separated on a preparative HPLC C18 column. Fractions active in the bioassay were then fractionated on a porous graphitic carbon column. The structures of the antifungal compounds cyclo(l-Phe-l-Pro), cyclo(l-Phe-trans-4-OH-l-Pro) and 3-phenyllactic acid (l/d isomer ratio, 9:1), were determined by nuclear magnetic resonance spectroscopy, mass spectrometry, and gas chromatography. MIC values against A. fumigatus and P. roqueforti were 20 mg ml?1 for cyclo(l-Phe-l-Pro) and 7.5 mg ml?1 for phenyllactic acid. Combinations of the antifungal compounds revealed weak synergistic effects. The production of the antifungal cyclic dipeptides cyclo(l-Phe-l-Pro) and cyclo(l-Phe-trans-4-OH-l-Pro) by lactic acid bacteria is reported here for the first time. PMID:12200282

  16. Synthesis of 1,5-benzothiazepine dipeptide mimetics via two CuI-catalyzed cross coupling reactions.

    PubMed

    Gan, Jiangang; Ma, Dawei

    2009-07-01

    CuI-catalyzed coupling of 4-methylphenyl bromide with amino acids gives N-aryl amino acids, which are converted into linear dipeptides via iodination and condensation with L-cysteine derived acyl chloride. Cyclization is achieved via a CuI/N,N-dimethylglycine catalyzed intramolecular coupling of aryl iodides with the liberated thiol to afford 1,5-benzothiazepine dipeptide mimetics. PMID:19480438

  17. Relative stability of major types of beta-turns as a function of amino acid composition: a study based on Ab initio energetic and natural abundance data.

    PubMed

    Perczel, András; Jákli, Imre; McAllister, Michael A; Csizmadia, Imre G

    2003-06-01

    Folding properties of small globular proteins are determined by their amino acid sequence (primary structure). This holds both for local (secondary structure) and for global conformational features of linear polypeptides and proteins composed from natural amino acid derivatives. It thus provides the rational basis of structure prediction algorithms. The shortest secondary structure element, the beta-turn, most typically adopts either a type I or a type II form, depending on the amino acid composition. Herein we investigate the sequence-dependent folding stability of both major types of beta-turns using simple dipeptide models (-Xxx-Yyy-). Gas-phase ab initio properties of 16 carefully selected and suitably protected dipeptide models (for example Val-Ser, Ala-Gly, Ser-Ser) were studied. For each backbone fold most probable side-chain conformers were considered. Fully optimized 321G RHF molecular structures were employed in medium level [B3LYP/6-311++G(d,p)//RHF/3-21G] energy calculations to estimate relative populations of the different backbone conformers. Our results show that the preference for beta-turn forms as calculated by quantum mechanics and observed in Xray determined proteins correlates significantly. PMID:12794897

  18. The smallest vertebrate, teleost fish, can utilize synthetic dipeptide-based diets.

    PubMed

    Dabrowski, Konrad; Lee, Kyeong-Jun; Rinchard, Jacques

    2003-12-01

    In vitro studies of brush-border intestinal transport of dipeptides and cytoplasmic hydrolysis in fish suggest that these processes could be key mechanisms in the absorption and utilization of nutrients for growth. However, in vivo experimentation to study the nutritional importance of these processes was needed. We compared three dietary formulations based on free, peptide and protein sources of amino acids. Our results were the first to show that a synthetic dipeptide (PP)-based diet could support growth in the early stages of ontogenesis of a teleost fish, rainbow trout (Oncorhynchus mykiss), whereas a free amino acid (FAA)-based diet failed. We found that fish fed an FAA-based diet had an increased rate of ammonia excretion [1.78 +/- 0.19 mmol NH(3)-N/(kg body wt.h)], compared with fish fed a PP-based diet [1.25 +/- 0.07 mmol NH(3)-N/(kg body wt.h)], suggesting that deamination is involved in the metabolism of dietary FAA. Teleost fish are known to obtain a high proportion of total energy from protein, compared with higher vertebrates. However, we found that feeding trout alevins a PP-based diet increased postprandial oxygen consumption for 2 to 24 h, whereas other treatments decreased 24-h postprandial metabolism. This may indicate that peptide metabolism is less efficient than protein metabolism. Juvenile rainbow trout differed from alevins in their response to FAA- and PP-based diets. These observations strongly suggest that intestinal dietary peptide transport and hydrolysis could support protein synthesis and growth in vertebrates that respond poorly to FAA-based diets. We conclude that nutrient administration may be improved by manipulating dietary peptide composition and peptide/protein ratios, leading to better utilization of synthetic peptides, with nutritional and therapeutic implications for all vertebrates. PMID:14652376

  19. Prebiotically plausible mechanisms increase compositional diversity of nucleic acid sequences

    E-print Network

    Nowak, Martin A.

    Prebiotically plausible mechanisms increase compositional diversity of nucleic acid sequences of life, the biological information of nucleic acid polymers must have increased to encode functional work suggests that prebiotically plausible chemical mechanisms of nucleic acid polymerization

  20. Dietary fat and the fatty acid composition of tissue lipids

    Microsoft Academic Search

    K. K. Carroll

    1965-01-01

    Some characteristics of the fatty acid composition of animal tissue lipids are described and the origins of tissue fatty acids\\u000a are discussed briefly. The effect of dietary fat on composition of tissue lipids is discussed. Types of dietary fatty acids\\u000a for which experimental work is described include polyunsaturated fatty acids, short-chain fatty acids, fatty acids with chain\\u000a length greater than

  1. 157 nm Photodissociation of a Complete Set of Dipeptide Ions Containing C-Terminal Arginine

    NASA Astrophysics Data System (ADS)

    He, Yi; Webber, Nathaniel; Reilly, James P.

    2013-05-01

    Twenty singly-charged dipeptide ions with C-terminal arginine were photodissociated with 157 nm light and their tandem mass spectra recorded. Many of the small product ions that were observed are standard peptide fragments that have been commonly seen in VUV photodissociation studies. However, the study of a library of dipeptides containing all 20 N-terminal amino acids enabled the recognition of trends associated with the occurrence of w-, v-, and immonium ions, the observation of competition between forming N- and C-terminal fragments in dipeptide RR, and the identification of some unusual fragment ions appearing at masses of 183, 187, 196, and 197 Da. A highly accurate internal calibration of the photodissociation TOF-TOF data enabled molecular formulae for these four product ions to be derived. Their proposed structures reflect the rather high-energy nature of this fragmentation phenomenon.

  2. Profiling histidine dipeptides in plasma and urine after ingesting beef, chicken or chicken broth in humans

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Reactive carbonyl species (RCS), oxidation products of polyunsaturated fatty acids, protein & sugars, play a role in the etiology of certain chronic diseases. Our previous studies revealed that histidine-dipeptides such as carnosine and anserine detoxify cytotoxic carbonyls such as 4-hydroxy-trans-...

  3. New potential renin inhibitors with dipeptide replacements in the molecule.

    PubMed

    Winiecka, Iwona; Dudkiewicz-Wilczy?ska, Jadwiga; Roman, Iza; Paruszewski, Ryszard

    2010-01-01

    A series of eight non-peptidic potential renin inhibitors have been designed and synthesized. All of them contain dipeptide replacement: (3S,4S)-4-amino-5-cyclohexyl-3-hydroxypentanoic acid (ACHPA) in their molecules. Four among them comprise two additional analogs of dipeptide: (3S,4S)-4-amino-3-hydroxy-5-phenylpentanoic acid (AHPPA) and (3S,4S)-4-amino-3-hydroxy-6-methylheptanoic acid (statine, Sta). All of the synthesized compounds contain also hydrophobic portions to receive a moderate lipophilicity of the molecules. Inhibitory activity of the compounds was measured in vitro by I-IPLC determination of Leu-Val-Tyr-Ser released from the N-acetyltetradecapeptide substrate by renin in the presence of the inhibitor. Asp-alpha(OEt)-(S,S)-ACHPA-epsilonAhx-Iaa (23) shows inhibitory activity (7%) at the concentration of 1.0 x 10(-2) M. The other synthesized compounds show no inhibitory activity up to this concentration. PMID:20635532

  4. Highly Cytotoxic Bioconjugated Gold(I) Complexes with Cysteine-Containing Dipeptides.

    PubMed

    Gutiérrez, Alejandro; Marzo, Isabel; Cativiela, Carlos; Laguna, Antonio; Gimeno, M Concepción

    2015-07-27

    Several gold(I) complexes with cysteine-containing dipeptides have been prepared starting from cystine by coupling different amino acids and using several orthogonal protections. The first step is the reaction of cystine, where the sulfur centre is protected as disulfide, with Boc2 O in order to protect the amino group, followed by coupling of an amino acid ester; finally the disulfide bridge is broken with mercaptoethanol to afford the dipeptide derivative. Further reaction with [AuCl(PPh3 )] gives the gold-dipeptide-phosphine species. Starting from these formally gold(I) thiolate-dipeptide phosphine complexes with the general formula [Au(SR)(PR3 )] different structural modifications, such as change in the type of the amino protecting group, the type of phosphine, the number of gold(I) atoms per molecule, or the use of a non-proteinogenic conformationally restricted amino acid ester, were introduced in order to evaluate their influence in the biological activity of the final complexes. The cytotoxic activity, in vitro, of these complexes was evaluated against different tumour human cell lines (A549, MiaPaca2 and Jurkat). The complexes show an outstanding cytotoxic activity with IC50 values in the very low micromolar range. Structure-activity relationship studies from the complexes open the possibility of designing more potent and promising gold(I) anticancer agents. PMID:26111275

  5. [Strategy for the development of dipeptide drugs].

    PubMed

    Gudasheva, T A

    2011-01-01

    The author describes an original approach to the development of dipeptide drugs based on the concept of the leading role of the beta-bend in the interaction of biologically active endogenous peptides with their receptors. The approach called "peptide-based drug design" includes both developments from the structure of a known psychotropic agent toward its topological peptide analog and developments from the active dipeptide site of a neuropeptide toward its mimetic. This strategy has been worked out at the V.V. Zakusov Research Institute of Pharmacology for 25 years. Results of investigations that discovered endogenous peptide prototypes of the known non-peptidic drugs (piracetam and sulpiride) are presented. They provided a basis for the creation of highly active non-toxic oral dipeptide preparations, such as nootrop Noopept, potential anti psychotic Dilept, and potential selective anxiolytic GB-115. PMID:21899085

  6. Muscle Histidine-Containing Dipeptides Are Elevated by Glucose Intolerance in Both Rodents and Men

    PubMed Central

    Stegen, Sanne; Everaert, Inge; Deldicque, Louise; Vallova, Silvia; de Courten, Barbora; Ukropcova, Barbara; Ukropec, Jozef; Derave, Wim

    2015-01-01

    Objective Muscle carnosine and its methylated form anserine are histidine-containing dipeptides. Both dipeptides have the ability to quench reactive carbonyl species and previous studies have shown that endogenous tissue levels are decreased in chronic diseases, such as diabetes. Design and Methods Rodent study: Skeletal muscles of rats and mice were collected from 4 different diet-intervention studies, aiming to induce various degrees of glucose intolerance: 45% high-fat feeding (male rats), 60% high-fat feeding (male rats), cafeteria feeding (male rats), 70% high-fat feeding (female mice). Body weight, glucose-tolerance and muscle histidine-containing dipeptides were assessed. Human study: Muscle biopsies were taken from m. vastus lateralis in 35 males (9 lean, 8 obese, 9 prediabetic and 9 newly diagnosed type 2 diabetic patients) and muscle carnosine and gene expression of muscle fiber type markers were measured. Results Diet interventions in rodents (cafeteria and 70% high-fat feeding) induced increases in body weight, glucose intolerance and levels of histidine-containing dipeptides in muscle. In humans, obese, prediabetic and diabetic men had increased muscle carnosine content compared to the lean (+21% (p>0.1), +30% (p<0.05) and +39% (p<0.05), respectively). The gene expression of fast-oxidative type 2A myosin heavy chain was increased in the prediabetic (1.8-fold, p<0.05) and tended to increase in the diabetic men (1.6-fold, p = 0.07), compared to healthy lean subjects. Conclusion Muscle histidine-containing dipeptides increases with progressive glucose intolerance, in male individuals (cross-sectional). In addition, high-fat diet-induced glucose intolerance was associated with increased muscle histidine-containing dipeptides in female mice (interventional). Increased muscle carnosine content might reflect fiber type composition and/or act as a compensatory mechanism aimed at preventing cell damage in states of impaired glucose tolerance. PMID:25803044

  7. Thermal properties of epoxy composites filled with boric acid

    NASA Astrophysics Data System (ADS)

    Visakh, P. M.; Nazarenko, O. B.; Amelkovich, Yu A.; Melnikova, T. V.

    2015-04-01

    The thermal properties of epoxy composites filled with boric acid fine powder at different percentage were studied. Epoxy composites were prepared using epoxy resin ED-20, boric acid as flame-retardant filler, hexamethylenediamine as a curing agent. The prepared samples and starting materials were examined using methods of thermal analysis, scanning electron microscopy and infrared spectroscopy. It was found that the incorporation of boric acid fine powder enhances the thermal stability of epoxy composites.

  8. Amino acid composition of humic substances in tundra soils

    NASA Astrophysics Data System (ADS)

    Vasilevich, R. S.; Beznosikov, V. A.

    2015-06-01

    Peripheral amino acid fragments of humic and fulvic acid molecules from tundra soils have been identified and quantified. A significant weight fraction of amino acids has been found in humic acid preparations, which exceeds their content in fulvic acids. Features of the amino acid composition of humic substances along the soil profile and depending on the degree of hydromorphism and the proportions of different (neutral, basic, acidic, cyclic) groups in amino acids have been revealed. The molar ratio between the hydroxy and heterocyclic amino acids reflects the degree of humification of the soil.

  9. ?-Mercaptoacyl dipeptides that inhibit angiotensin converting enzyme and neutral endopeptidase 24.11

    Microsoft Academic Search

    Shripad S. Bhagwat; Cynthia A. Fink; Candido Gude; Kenneth Chan; Ying Qiao; Yumi Sakane; Carol Berry; Raj D. Ghai

    1995-01-01

    ?-Mercaptoacyl dipeptides were prepared and found to inhibit angiotensin converting enzyme (ACE) and neutral endopeptidase 24.11 (NEP). Compounds with a proline as the C-terminal amino acid, and possessing the S-stereochemistry at the thiol bearing carbon were preferred for optimal ACE inhibition while, R-stereochemistry was preferred for optimal NEP inhibition. Compounds containing alternative amino acid residues at the C-terminal position displayed

  10. Influence of dietary essential fatty acid level on fatty acid composition in peripheral nerve and muscle

    E-print Network

    Paris-Sud XI, Université de

    Influence of dietary essential fatty acid level on fatty acid composition in peripheral nerve fed with diets containing different levels of essential unsaturated fatty acids, namely linoleic (18 :2 (n-6)) and linolenic (18 : 2 (n-3)) acid, in the oil. Nerve and muscle fatty acids were analyzed

  11. Syntheses of Norstatine, Its Analogs, and Dipeptide Isosteres by Means of ?-Lactam Synthon Method.

    PubMed

    Ojima, I; Delaloge, F

    1999-01-01

    Nonprotein amino acids are the amino acids that are not found in protein-main chains and mostly originate in plants, microorganisms, and marine products. Certain nonprotein amino acids exhibit biological activities by themselves, and many of them are important constituents of biologically active compounds of medicinal interest. For this reason, in addition to the naturally occurring nonprotein amino acids, synthetic nonprotein amino acids have been studied extensively, especially in connection with the design and synthesis of various enzyme inhibitors. Indeed, statine, norstatine, and their analogs, as well as a variety of dipeptide isosteres, have been developed and incorporated in various inhibitors of enzymes such as renin and HIV-1 protease with great success (1). These amino acid residues and their isosteres provide effective transition-state mimics of the substrates for peptidases that bind to these enzymes tightly and inhibit their actions. Although a number of methods has been reported for the synthesis of statine and its analogs (2-7), to date, only a few synthetic methods are available for norstatine and its analogs (8-12). The ?-lactam synthon method developed by these laboratories (13-17) can be effectively applied to the asymmetric synthesis of norstatine and its analogs, as well as various dipeptide isosteres. In this chapter, the preparation of 3-siloxy-?-lactams will be described first, followed by those of norstatine and its analogs, as well as dihydroxyethylene, hydroxyethylamine and other dipeptide isosteres. PMID:21380896

  12. Organic acids and sugars composition of harvested pomegranate fruits

    Microsoft Academic Search

    Pablo Melgarejo; Domingo Manuel Salazar; F. Artés

    2000-01-01

    For two consecutive seasons, 40 Spanish pomegranate cultivars (cvs) were analysed and their individual organic acids and\\u000a sugars compositions were examined. Intervarietal differences in acidity content reported by different authors were confirmed.\\u000a According to organoleptic characteristics and chemical compositions three groups of varieties were established: sweet (SWV),\\u000a soursweet (SSWV) and sour (SV). On average, for two seasons, total organic acids

  13. Isotope composition of carbon in amino acids of solid bitumens

    NASA Astrophysics Data System (ADS)

    Shanina, S. N.; Bushnev, D. A.

    2014-06-01

    Primary data are presented on the isotope composition of carbon in individual amino acids from solid bitumens and several biological objects. The amino acids of biological objects are characterized by wide variations of the isotope composition of carbon. This fact occurs owing to the difference in biochemical paths of metabolism resulting in the synthesis of individual amino acids. The ?13C values are somewhat decreased for individual amino acids in asphaltenes, varying from -7.7 to -31.7‰. The carbon of amino acids is weighted in kerits from Bad'el' compared to asphaltenes. All the natural bitumens retain the characteristic trend for natural substances: the isotopically heavy and light amino acids by carbon are glycine and leucine, respectively. The isotope composition of amino-acid carbon is lightened compared to natural bitumens in the samples formed under a pronounced thermal impact (asphalt-like crust and kirishite).

  14. Fatty acid composition of human milk in Western Iran

    Microsoft Academic Search

    G Bahrami; Z Rahimi

    2005-01-01

    Objective:To investigate the fatty acid composition of mature human milk in Western Iran with special focus on trans fatty acids.Design:Observational study.Methods:Milk samples were collected from 52 lactating mothers aging 19–39 y, from Western Iran. Subjects were asked to complete a diet questionnaire. Milk fatty acids were measured as 2-nitrophenylhydrazide derivatives by high-performance liquid chromatography.Results:Saturated fatty acids were the main fraction

  15. Fatty Acid Composition and Volatile Constituents of Protaetia brevitarsis Larvae

    PubMed Central

    Yeo, Hyelim; Youn, Kumju; Kim, Minji; Yun, Eun-Young; Hwang, Jae-Sam; Jeong, Woo-Sik; Jun, Mira

    2013-01-01

    A total of 48 different volatile oils were identified form P. brevitarsis larvae by gas chromatography/mass spectrometry (GC/MS). Acids (48.67%) were detected as the major group in P. brevitarsis larvae comprising the largest proportion of the volatile compounds, followed by esters (19.84%), hydrocarbons (18.90%), alcohols (8.37%), miscellaneous (1.71%), aldehydes (1.35%) and terpenes (1.16%). The major volatile constituents were 9-hexadecenoic acid (16.75%), 6-octadecenoic acid (14.88%) and n-hexadecanoic acid (11.06%). The composition of fatty acid was also determined by GC analysis and 16 fatty acids were identified. The predominant fatty acids were oleic acid (C18:1, 64.24%) followed by palmitic acid (C16:0, 15.89%), palmitoleic acid (C16:1, 10.43%) and linoleic acid (C18:2, 4.69%) constituting more than 95% of total fatty acids. The distinguished characteristic of the fatty acid profile of P. brevitarsis larvae was the high proportion of unsaturated fatty acid (80.54% of total fatty acids) versus saturated fatty acids (19.46% of total fatty acids). Furthermore, small but significant amounts of linoleic, linolenic and ?-linolenic acids bestow P. brevitarsis larvae with considerable nutritional value. The novel findings of the present study provide a scientific basis for the comprehensive utilization of the insect as a nutritionally promising food source and a possibility for more effective utilization. PMID:24471125

  16. Biliary lipid composition in idiopathic bile acid malabsorption

    PubMed Central

    Fracchia, M; Pellegrino, S; Secreto, P; Pera, A; Galatola, G

    1998-01-01

    Background—Chronic diarrhoea is the clinical hallmark of patients presenting with idiopathic bile acid malabsorption. Its pathogenesis is unknown; colonic water secretion can be induced by dihydroxy bile acids, but it is not known whether enrichment of the bile acid pool with these bile acids occurs in such patients. Furthermore, bile acid malabsorption is known to affect biliary lipid composition, but no information is available for the idiopathic type. ?Aims—To verify: (a) whether diarrhoea in patients with idiopathic bile acid malabsorption is associated with enrichment of the bile acid pool with dihydroxy bile acids; and (b) whether supersaturation with cholesterol of duodenal bile occurs in such patients as a result of chronic bile acid depletion. ?Patients—Thirteen patients with idiopathic bile acid malabsorption diagnosed according to abnormal 75SeHCAT test and absence of other organic diseases, and 23 control subjects. ?Methods—Bile rich duodenal fluid was collected during intravenous ceruletide infusion in the fasting state. Biliary lipids were analysed by enzymatic assays and bile acids by high performance liquid chromatography. ?Results—Patients with idiopathic bile acid malabsorption had a cholesterol saturation index similar to controls. Bile acid composition showed only a decrease in percentage cholic acid (29(2)% versus 36 (2)%; p<0.05); the dihydroxy:trihydroxy bile acid ratio was similar to controls. ?Conclusions—Patients with idiopathic bile acid malabsorption do not have an increased risk of forming cholesterol gallstones. The mechanism of diarrhoea does not seem to depend on an enrichment of the bile acid pool with dihydroxy bile acids. ?? Keywords: primary bile acid malabsorption; bile acids; diarrhoea; 75SeHCAT; biliary lipids; cholesterol saturation index PMID:9824609

  17. Genomic Regions Associated with Amino Acid Composition in Soybean

    Microsoft Academic Search

    D. R. Panthee; V. R. Pantalone; A. M. Saxton; D. R. West; C. E. Sams

    2006-01-01

    Soybean [Glycine max (L.) Merr.] is the single largest source of protein in animal feed. However, few studies have been conducted to evaluate\\u000a genomic regions controlling amino acid composition in soybean. It is important to study the genetics of amino acid composition\\u000a to achieve improvements through breeding. The objectives of this study were to determine the ratios between essential to

  18. FATTY ACID COMPOSITION OF EGGS ENRICHED WITH OMEGA -3 FATTY ACIDS ON THE MARKET

    Microsoft Academic Search

    Vekoslava STIBILJ; Mojca KOMAN; Antonija HOLCMAN

    1999-01-01

    The aim of our work was to determine fatty acid content in eggs enriched with omega-3 polyunsaturated fatty acids from various producers on the market. Due to simplicity, speed and reduced organic solvent usage, we used the in situ trans-esterification ISTE method for the determination of the fatty acid composition in eggs. The method was checked by the analysis of

  19. 4-Substituted boro-proline dipeptides: synthesis, characterization, and dipeptidyl peptidase IV, 8, and 9 activities.

    PubMed

    Wu, Wengen; Liu, Yuxin; Milo, Lawrence J; Shu, Ying; Zhao, Peng; Li, Youhua; Woznica, Iwona; Yu, Gengli; Sanford, David G; Zhou, Yuhong; Poplawski, Sarah E; Connolly, Beth A; Sudmeier, James L; Bachovchin, William W; Lai, Jack H

    2012-09-01

    The boroProline-based dipeptidyl boronic acids were among the first DPP-IV inhibitors identified, and remain the most potent known. We introduced various substitutions at the 4-position of the boroProline ring regioselectively and stereoselectively, and incorporated these aminoboronic acids into a series of 4-substituted boroPro-based dipeptides. Among these dipeptidyl boronic acids, Arg-(4S)-boroHyp (4q) was the most potent inhibitor of DPP-IV, DPP8 and DPP9, while (4S)-Hyp-(4R)-boroHyp (4o) exhibited the most selectivity for DPP-IV over DPP8 and DPP9. PMID:22853995

  20. Evidence for di-peptide uptake in Tetrahymena.

    PubMed

    Rasmussen, L; Zdanowski, M K

    1980-09-15

    We have established growth conditions in a synthetic nutrient medium in such a way that utilization of free phenylalanine, but not of phenylalanine-containing di-peptides, limits cell multiplication in species of the genus Tetrahymena (Ciliata). These results suggest that these cells take up intact di-peptides. PMID:6903157

  1. Bestatin induces specific changes in Trypanosoma cruzi dipeptide pool.

    PubMed

    Trochine, Andrea; Creek, Darren J; Faral-Tello, Paula; Barrett, Michael P; Robello, Carlos

    2015-05-01

    Proteases and peptidases in Trypanosoma cruzi are considered potential targets for antichagasic chemotherapy. We monitored changes in low-mass metabolites in T. cruzi epimastigotes treated with bestatin, a dipeptide metalloaminopeptidase inhibitor. After treatment, multiple dipeptides were shown to be increased, confirming in situ inhibition of the leucine aminopeptidase of T. cruzi (LAPTc) and probably other peptidases. PMID:25712359

  2. Wear performance of some phenolic composites with boric acid

    Microsoft Academic Search

    I. Mutlu; C. Oner; I. Cevik; F. Findik

    2007-01-01

    Purpose – The aim of the research is to investigate wear performance of some phenolic composites with boric acid. Design\\/methodology\\/approach – The brake lining which has new formulation has been produced by using various additive materials. Various techniques have been used in the production of brake lining. These phenolic composites were subjected to friction and wear tests under different loads,

  3. Thermal properties of poly (lactic acid)/milkweed composites

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Currently, most polymer composites utilize petroleum-based materials that are non-degradable and difficult to recycle or incur substantial cost for disposal. Green composites can be used in nondurable limited applications. In order to determine the degree of compatibility between Poly (lactic Acid...

  4. N-(L-2-aminopentanoyl)-L-phenylalanine dihydrate, a hydrophobic dipeptide with a nonproteinogenic residue.

    PubMed

    Görbitz, Carl Henrik; Yadav, Vitthal N

    2013-09-01

    The title dipeptide, better known as L-norvalyl-L-phenylalanine {systematic name: (S)-2-[(S)-2-aminopentanamido]-3-phenylpropanoic acid dihydrate}, C14H20N2O3·2H2O, has a nonproteinogenic N-terminal residue. In the solid state, it takes on a molecular conformation typical for one of the three classes of nanoporous dipeptides, but like two related compounds with a hydrophobic N-terminal residue and a C-terminal L-phenylalanine, it fails to form channels or pores. Instead, the crystal structure is divided into distinct hydrophobic and hydrophilic layers, the latter encompassing cocrystallized water molecules connecting the charged N- and C-terminal groups. PMID:24005523

  5. Gas-chromatographic separation of stereoisomers of dipeptides.

    PubMed

    Pätzold, Ralf; Theis, Christoph; Brückner, Hans

    2006-08-01

    Synthetic dipeptides comprising mixtures of enantiomers, diastereomers, or sequential isomers were converted into their N-perfluoroacetyl dipeptide esters (perfluoroacetyl: trifluoroacetyl, pentafluoroacetyl, heptafluorobutyryl; ester: methyl, 1-propyl, 2-propyl, 2,2,2-trifluoroethyl) and analyzed by GC-MS on the chiral stationary phases Chirasil-L-Val and Lipodex-E using helium as carrier gas. Further, dipeptides were converted into their N-trifluoroacetyl dipeptide S-(+)-2-butyl esters and separated on achiral phenylmethyl polysiloxane column (HP-5 MS). Derivatization of dipeptides was performed at ambient temperature in order to avoid formation of the corresponding diketopiperazines. The best separation of stereoisomers was achieved with TFA and PFP methyl esters on Chirasil-L-Val. PMID:16683229

  6. Evolutionary Conservation of Amino Acid Composition in Paralogous Insect Vitellogenins

    PubMed Central

    Hughes, Austin L.

    2010-01-01

    Comparison of paralogous vitellogenins in 10 insect species representing six orders showed a remarkable degree of conservation of amino acid composition in spite of sequence differences. For example, the correlation between the percentages of the 20 amino acids in two vitellogenins from the beetle Tribolium castaneum was 0.975, even though the two amino acid sequences differed from each other at 49.4% of sites. There was a positive correlation between the frequency of occurrence of reciprocal pairs of amino acids in more distantly related paralogs, and this correlation was generally strongest when both of the amino acids in the pair were nutritionally essential. These results imply that conservation of amino acid composition occurs through amino acid replacements that result in a balanced loss and gain of each amino acid each amino acid residue. Thus insect vitellogenins seem to be subject to an unusual kind of purifying selection, where the amino acid content is conserved rather than the sequence per se, selection apparently arising from the nutritional needs of the developing embryo appears to be responsible for maintaining the balance of amino acids. PMID:20655995

  7. Polyunsaturated fatty acid saturation by gut lactic acid bacteria affecting host lipid composition

    PubMed Central

    Kishino, Shigenobu; Takeuchi, Michiki; Park, Si-Bum; Hirata, Akiko; Kitamura, Nahoko; Kunisawa, Jun; Kiyono, Hiroshi; Iwamoto, Ryo; Isobe, Yosuke; Arita, Makoto; Arai, Hiroyuki; Ueda, Kazumitsu; Shima, Jun; Takahashi, Satomi; Yokozeki, Kenzo; Shimizu, Sakayu; Ogawa, Jun

    2013-01-01

    In the representative gut bacterium Lactobacillus plantarum, we identified genes encoding the enzymes involved in a saturation metabolism of polyunsaturated fatty acids and revealed in detail the metabolic pathway that generates hydroxy fatty acids, oxo fatty acids, conjugated fatty acids, and partially saturated trans-fatty acids as intermediates. Furthermore, we observed these intermediates, especially hydroxy fatty acids, in host organs. Levels of hydroxy fatty acids were much higher in specific pathogen-free mice than in germ-free mice, indicating that these fatty acids are generated through polyunsaturated fatty acids metabolism of gastrointestinal microorganisms. These findings suggested that lipid metabolism by gastrointestinal microbes affects the health of the host by modifying fatty acid composition. PMID:24127592

  8. Variation in amino acid and lipid composition of latent fingerprints.

    PubMed

    Croxton, Ruth S; Baron, Mark G; Butler, David; Kent, Terry; Sears, Vaughn G

    2010-06-15

    The enhancement of latent fingerprints, both at the crime scene and in the laboratory using an array of chemical, physical and optical techniques, permits their use for identification. Despite the plethora of techniques available, there are occasions when latent fingerprints are not successfully enhanced. An understanding of latent fingerprint chemistry and behaviour will aid the improvement of current techniques and the development of novel ones. In this study the amino acid and fatty acid content of 'real' latent fingerprints collected on a non-porous surface was analysed by gas chromatography-mass spectrometry. Squalene was also quantified in addition. Hexadecanoic acid, octadecanoic acid and cis-9-octadecenoic acid were the most abundant fatty acids in all samples. There was, however, wide variation in the relative amounts of each fatty acid in each sample. It was clearly demonstrated that touching sebum-rich areas of the face immediately prior to fingerprint deposition resulted in a significant increase in the amount of fatty acids and squalene deposited in the resulting 'groomed' fingerprints. Serine was the most abundant amino acid identified followed by glycine, alanine and aspartic acid. The significant quantitative differences between the 'natural' and 'groomed' fingerprint samples seen for fatty acids were not observed in the case of the amino acids. This study demonstrates the variation in latent fingerprint composition between individuals and the impact of the sampling protocol on the quantitative analysis of fingerprints. PMID:20413233

  9. Antioxidation status and histidine dipeptides content in broiler blood and muscles depending on protein sources in feed.

    PubMed

    Kope?, W; Jamroz, D; Wiliczkiewicz, A; Biazik, E; Hikawczuk, T; Skiba, T; Pud?o, A; Orda, J

    2013-06-01

    One-day-old chickens were fed mixtures containing different raw materials (fish by-products meal, porcine blood cells meal, blood meal, wheat gluten, fodder yeast), as a source of histidine and ?-alanine - components of carnosine. Control birds were administered a feed mixture, in which soy bean meal was the main protein source. The bodyweight, feed consumption and conversion, antioxidant characteristics and histidine dipeptides content in blood and muscles, and also amino acid composition of chicken meat on day?34 post-hatch were recorded. The best (p?acids content in feed mixtures and in meat were observed. PMID:22533382

  10. Metal array fabrication based on ultrasound-induced self-assembly of metalated dipeptides.

    PubMed

    Isozaki, Katsuhiro; Haga, Yusuke; Ogata, Kazuki; Naota, Takeshi; Takaya, Hikaru

    2013-12-01

    Pd- and Pt-bound bis-metalated peptides were synthesised by the condensation of Pd- or Pt-aldimine-complex-bound glutamic acids to afford the four possible metal isomers of bis-Pd and bis-Pt-homometalated dipeptides and PdPt- and PtPd-heterometalated dipeptides without metal disproportionation. Ultrasound-induced self-assembly of these bis-metalated peptides proceeded effectively to afford supramolecular gels that displayed well-ordered metal arrays. The formation of parallel ?-sheet type aggregates through interpeptide amide-amide hydrogen bonding was confirmed by IR, scanning electron microscopy (SEM), and synchrotron X-ray diffraction analyses (WAXS and SAXS). The mechanism of the ultrasound-induced self-assembly of the metalated dipeptides was elucidated via kinetic and association experiments by (1)H NMR, in which ultrasound-triggered dissociation of intramolecular hydrogen bonds between the chloride ligands of the Pd- and Pt-complexes and amides initially occurred. This was followed by the formation of intermolecular amide-amide hydrogen bonds, which afforded the corresponding oligomeric peptide self-assembly as the nucleus for supramolecular aggregation. The observed first-order relationship of the gelation rate versus the sonication frequency suggested that the microcavitation generated under sonication conditions acted as a crucial trigger and provided a reaction field for efficient self-assembly. PMID:23963158

  11. Tryptophan-containing dipeptides are C-domain selective inhibitors of angiotensin converting enzyme.

    PubMed

    Lunow, Diana; Kaiser, Susanne; Rückriemen, Jana; Pohl, Christoph; Henle, Thomas

    2015-01-01

    Somatic angiotensin-converting enzyme (ACE) contains two active sites, the C- and N-domain, from which the C-domain is supposed to play a major role in blood pressure regulation and is therefore a promising pharmacological target to reduce blood pressure without side-effects. We report for the first time that tryptophan-containing dipeptides such as Ile-Trp or Val-Trp, which were recently found in food protein hydrolysates, are selective and competitive inhibitors for the C-domain with a selectivity factor of 40 and 70, respectively. Structure-activity studies showed that an N-terminal aliphatic amino acid and a tryptophan moiety in the P2' position are favourable structures for C-domain inhibition in dipeptides. In contrast, the lactotripeptides Ile-Pro-Pro and Val-Pro-Pro, which were widely used as ingredients for hypotensive food, showed a slight selectivity for the N-domain. Hence, tryptophan containing dipeptides are interesting ingredients for functional foods as a natural prevention for hypertension with reduced side effects due to its selective inhibition of the C-domain. PMID:25053098

  12. Effets d'une carence en acides gras essentiels sur la composition en acides gras des muscle,

    E-print Network

    Paris-Sud XI, Université de

    of an essential fatty acid deficiency on the fatty acid composition of muscle, liver and adipose tissue in female trout (Salmo gairdneri) during sexual cycle. Fatty acid composition of adipose tissue, muscle and liver highly dependent on the nature of diet, in particular in LN fraction. In muscle and liver n-3 fatty acid

  13. Fatty acid composition in native and cultured human endothelial cells

    Microsoft Academic Search

    M. Lagarde; B. Sicard; M. Guichardant; O. Felisi; M. Dechavanne

    1984-01-01

    Summary  Endothelial cells from human umbilical veins were isolated by collagenase treatment. Cells were cultured in the presence of\\u000a either 20% fetal bovine serum (FBS) or 20% human serum (HS). At confluency, endothelial cell lipids were labeled with tracer\\u000a concentrations of tritiated arachidonic acid, then extracted and separated into lipid subclasses by thin layer chromatography.\\u000a The fatty acid composition of each

  14. Modification of the fatty acid composition of bovine tissues 

    E-print Network

    Chang, Joyce

    1990-01-01

    , quantitating the activity of the enzymes involved in the conversion of saturated to unsaturated fatty acids in intestine, liver, muscle and adipose tissue will be a second objective of this study. In addition, these enzyme systems will be studied... in liver and adipose tissue, thereby affecting the composition of 10 the fatty acids in those tissues. Along with physical activity, obesity seems to also play a role in the regulation of the desaturase enzyme. A suggested mechanism by which physical...

  15. Nucleic acids, compositions and uses thereof

    DOEpatents

    Preston, III, James F. (Micanopy, FL); Chow, Virginia (Gainesville, FL); Nong, Guang (Gainesville, FL); Rice, John D. (Gainesville, FL); St. John, Franz J. (Baltimore, MD)

    2012-02-21

    The subject invention provides at least one nucleic acid sequence encoding an aldouronate-utilization regulon isolated from Paenibacillus sp. strain JDR-2, a bacterium which efficiently utilizes xylan and metabolizes aldouronates (methylglucuronoxylosaccharides). The subject invention also provides a means for providing a coordinately regulated process in which xylan depolymerization and product assimilation are coupled in Paenibacillus sp. strain JDR-2 to provide a favorable system for the conversion of lignocellulosic biomass to biobased products. Additionally, the nucleic acid sequences encoding the aldouronate-utilization regulon can be used to transform other bacteria to form organisms capable of producing a desired product (e.g., ethanol, 1-butanol, acetoin, 2,3-butanediol, 1,3-propanediol, succinate, lactate, acetate, malate or alanine) from lignocellulosic biomass.

  16. Nucleic acid compositions and the encoding proteins

    DOEpatents

    Preston, III, James F.; Chow, Virginia; Nong, Guang; Rice, John D.; St. John, Franz J.

    2014-09-02

    The subject invention provides at least one nucleic acid sequence encoding an aldouronate-utilization regulon isolated from Paenibacillus sp. strain JDR-2, a bacterium which efficiently utilizes xylan and metabolizes aldouronates (methylglucuronoxylosaccharides). The subject invention also provides a means for providing a coordinately regulated process in which xylan depolymerization and product assimilation are coupled in Paenibacillus sp. strain JDR-2 to provide a favorable system for the conversion of lignocellulosic biomass to biobased products. Additionally, the nucleic acid sequences encoding the aldouronate-utilization regulon can be used to transform other bacteria to form organisms capable of producing a desired product (e.g., ethanol, 1-butanol, acetoin, 2,3-butanediol, 1,3-propanediol, succinate, lactate, acetate, malate or alanine) from lignocellulosic biomass.

  17. Marked difference in self-assembly, morphology, and cell viability of positional isomeric dipeptides generated by reversal of sequence.

    PubMed

    Kar, Sudeshna; Tai, Yian

    2015-02-01

    In this study two positional isomeric dipeptides Boc-m-ABA-Aib-OMe () and Boc-Aib-m-ABA-OMe () synthesized by reversal of the positions of two rigid amino acids (m-ABA: m-aminobenzoic acid, Aib: ?-aminoisobutyric acid) showed marked difference in morphology under the same environmental conditions. Investigation of single crystal structures reveals the difference in crystal packing and higher order self-assembly pattern for both the isomeric peptides, which might be the responsible factor for their different morphological patterns. Moreover, these isomeric dipeptides have produced different cellular viability effects towards normal bone cells. These two peptides would have utilities in the model study of isomeric peptides/proteins, where morphological difference under identical conditions brings changes in their individual bio-activities and where the reversal of sequence causes different cellular viability and generates health hazard. PMID:25574757

  18. THERMAL PROPERTIES OF POLY (LACTIC ACID) BASED BIO-COMPOSITES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The degree of compatibility between polylactic acid (PLA) and different bio-fillers was examined using thermal methods. The biofillers were fibers extracted from cuphea and lesquerella seeds. Cuphea and lasquerella are non-commercial seed crops. Bio-composites with PLA:Fiber ratios of 85:15, 70:3...

  19. Original article Variation in fatty acid composition of milk and

    E-print Network

    Paris-Sud XI, Université de

    of milk, and derived cheese, when dairy cows were grazed on different alpine vegetation types and cheeses varied with the type of vegetation. Milk and cheese derived from cows that were grazedOriginal article Variation in fatty acid composition of milk and cheese from cows grazed on two

  20. An Index to Deoxyribonucleic Acid Base Compositions of Bacterial Species

    Microsoft Academic Search

    L. R. Hill

    1966-01-01

    SUMMARY This paper consists of a reference list of bacterial species for which deoxyribonucleic acid base compositions are known. Culture-collection strain numbers have been included wherever possible. The compilation may also provide a basis for the inclusion of these data into species descriptions. the authors are given in parenthesis. The only exceptions are: 'Diplococcus' is included in Streptococcus; ' Coxiella'

  1. Oleuropein on lipid and fatty acid composition of rat heart

    Microsoft Academic Search

    Valentina Ruíz-Gutiérrez; Francisco J. G. Muriana; Roberto Maestro; Enrique Graciani

    1995-01-01

    Male rats of the Wistar strain were given oleuropein for 3 weeks at a dose of 25 or 50 mg\\/kg of body weight. Heart samples were analyzed for the lipid composition by the Iatroscan TLCFID technique and for the fatty acid profile of neutral and polar lipids by the capillary gas chromatography. In addition, the oleuropein, ?- and ?-tocopherol content

  2. Effects of Biomass in Polyethylene or Polylactic Acid Composites

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Previous studies have shown that compounding Polyethylene (PE) or Polylactic acid (PLA) with a dairy-based bioplastic resulted in composites with good mechanical properties. In this study, mass ratios of a dairy-protein-based material (DBP) ranging from 0, 5, 10 and 20 wt% replaced equivalent masse...

  3. Nanofiber composite membranes with low equivalent weight perfluorosulfonic acid polymers

    E-print Network

    Mather, Patrick T.

    Nanofiber composite membranes with low equivalent weight perfluorosulfonic acid polymers Jonghyun February 2010, Accepted 5th May 2010 DOI: 10.1039/c0jm00441c Two low equivalent weight perfluorosulfonic as little as 0.3 wt% of high molecular weight poly(ethylene oxide) as a carrier polymer. The electrospun

  4. SUGAR BEET PULP AND POLY (LACTIC ACID) GREEN COMPOSITES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biodegradable composite materials of sugar beet pulp (SBP) and poly (lactic acid)(PLA) were compounded using a twin-screw extruder, molded by injection molding and evaluated for structural, mechanical, and moisture resistant properties, as well as biodegradability. Microscopic analysis revealed tha...

  5. Deoxyribonucleic acid base compositions of dermatophytes.

    PubMed

    Davison, F D; Mackenzie, D W; Owen, R J

    1980-06-01

    DNA was extracted and purified from 55 dermatophyte isolates representing 34 species of Trichophyton, Microsporum and Epidermophyton. The base compositions of the chromosomal DNA were determined by CsCl density gradient centrifugation and were found to be in the narrow range of 48.7 to 50.3 mol % G + C. A satellite DNA component assumed to be of mitochondrial origin was present in most strains, with a G + C content ranging from 14.7 to 30.8 mol % G + C. Heterogeneity in microscopic and colonial characteristics was not reflected in differences in the mean G + C content of the chromosomal DNAs. Strains varied in the G + C contents of satelite DNA, but these did not correlate with traditional species concepts. PMID:7441200

  6. Group composition of carboxylic acids from West Siberian crude oils

    SciTech Connect

    Zhic'tsov, N.I.; Ershov, V.A.; Samokhvalova, G.I.

    1982-11-01

    Performs mass spectrometric analyses of carboxylic acids from crudes of different geologic ages using an MAT 111 chromatograph/mass spectrometer equipped with systems for direct sample introduction and temperature programming. Explains that as an analytical characteristic for determination of the group composition and molecular weight distribution of the carboxylic, the relative intensities of peaks of the ions (M-15)/sup +/ were selected in the mass spectra of their trimethylsilyl esters (TMSES), obtained at different temperatures of the sample in the ion source. Concludes that the results from an analysis of the group composition of the carboxylic acids in crude oils from 10 deposits of various geological ages indicate that as the metamorphism factor increases, there is a decrease in the content of naphthenic acids in the acid concentrates from the crudes. Offers the possibility that for higher reservoir temperatures and greater depths of occurrence of the oil-enclosing rock, the reducing factor dominates over the oxidizing factor in making up the composition of the petroleum acids.

  7. Total Fat Intake Modifies Plasma Fatty Acid Composition in Humans1

    Microsoft Academic Search

    Susan K. Raatz; Douglas Bibus; William Thomas; Penny Kris-Etherton

    Plasma fatty acid composition reflects dietary fatty acids. Whether the total fat content of the diet alters the fatty acid composition of plasma phospholipid, cholesteryl ester, triacylglycerol and free fatty acids is unknown. To evaluate the effects of low versus high fat diets on plasma fatty acids, a 12-wk, randomized, crossover, controlled feeding trial was conducted in healthy men and

  8. Pyrrolidinyl PNA with ?/?-Dipeptide Backbone: From Development to Applications.

    PubMed

    Vilaivan, Tirayut

    2015-06-16

    The specific pairing between two complementary nucleobases (A·T, C·G) according to the Watson-Crick rules is by no means unique to natural nucleic acids. During the past few decades a number of nucleic acid analogues or mimics have been developed, and peptide nucleic acid (PNA) is one of the most intriguing examples. In addition to forming hybrids with natural DNA/RNA as well as itself with high affinity and specificity, the uncharged peptide-like backbone of PNA confers several unique properties not observed in other classes of nucleic acid analogues. PNA is therefore suited to applications currently performed by conventional oligonucleotides/analogues and others potentially beyond this. In addition, PNA is also interesting in its own right as a new class of oligonucleotide mimics. Unlimited opportunities exist to modify the PNA structure, stimulating the search for new systems with improved properties or additional functionality not present in the original PNA, driving future research and applications of these in nanotechnology and beyond. Although many structural variations of PNA exist, significant improvements to date have been limited to a few constrained derivatives of the privileged N-2-aminoethylglycine PNA scaffold. In this Account, we summarize our contributions in this field: the development of a new family of conformationally constrained pyrrolidinyl PNA having a nonchimeric ?/?-dipeptide backbone derived from nucleobase-modified proline and cyclic ?-amino acids. The conformational constraints dictated by the pyrrolidine ring and the ?-amino acid are essential requirements determining the binding efficiency, as the structure and stereochemistry of the PNA backbone significantly affect its ability to interact with DNA, RNA, and in self-pairing. The modular nature of the dipeptide backbone simplifies the synthesis and allows for rapid structural optimization. Pyrrolidinyl PNA having a (2'R,4'R)-proline/(1S,2S)-2-aminocyclopentanecarboxylic backbone (acpcPNA) binds to DNA with outstanding affinity and sequence specificity. It also binds to RNA in a highly sequence-specific fashion, albeit with lower affinity than to DNA. Additional characteristics include exclusive antiparallel/parallel selectivity and a low tendency for self-hybridization. Modification of the nucleobase or backbone allowing site-specific incorporation of labels and other functions to acpcPNA via click and other conjugation chemistries is possible, generating functional PNAs that are suitable for various applications. DNA sensing and biological applications of acpcPNA have been demonstrated, but these are still in their infancy and the full potential of pyrrolidinyl PNA is yet to be realized. With properties competitive with, and in some aspects superior to, the best PNA technology available to date, pyrrolidinyl PNA offers great promise as a platform system for future elaboration for the fabrication of new functional materials, nanodevices, and next-generation analytical tools. PMID:26022340

  9. Fatty acid composition of Swedish bakery products, with emphasis on trans-fatty acids.

    PubMed

    Trattner, Sofia; Becker, Wulf; Wretling, Sören; Öhrvik, Veronica; Mattisson, Irene

    2015-05-15

    Trans-fatty acids (TFA) have been associated with increased risk of coronary heart disease, by affecting blood lipids and inflammation factors. Current nutrition recommendations emphasise a limitation of dietary TFA intake. The aim of this study was to investigate fatty acid composition in sweet bakery products, with emphasis on TFA, on the Swedish market and compare fatty acid composition over time. Products were sampled in 2001, 2006 and 2007 and analysed for fatty acid composition by using GC. Mean TFA levels were 0.7% in 2007 and 5.9% in 2001 of total fatty acids. In 1995-97, mean TFA level was 14.3%. In 2007, 3 of 41 products had TFA levels above 2% of total fatty acids. TFA content had decreased in this product category, while the proportion of saturated (SFA) and polyunsaturated (PUFA) fatty acids had increased, mostly through increased levels of 16:0 and 18:2 n-6, respectively. The total fat content remained largely unchanged. PMID:25577101

  10. U373MG cells express PepT2 and accumulate the fluorescently tagged dipeptide-derivative ?-Ala-Lys-N ?-AMCA

    Microsoft Academic Search

    Mathias Zimmermann; Kai Kappert; Alexandru Constantin Stan

    2010-01-01

    Aim of this study was to examine the dipeptide transport of ?-Ala-Lys-N?-AMCA in the human glioma cell line U373-MG and its potential regulation by diverse hormones and culture media. A mixed glial primary cell culture of the newborn rat served as reference cell system. ?-Ala-Lys-N?-AMCA (?-Ala-Lys-N?-7-amino-4-methyl-coumarin-3-acetic acid) is a highly specific reporter substrate to investigate the dipeptide transport system PepT2.

  11. Inter-domain linker prediction using amino acid compositional index.

    PubMed

    Shatnawi, Maad; Zaki, Nazar

    2015-04-01

    Protein chains are generally long and consist of multiple domains. Domains are distinct structural units of a protein that can evolve and function independently. The accurate and reliable prediction of protein domain linkers and boundaries is often considered to be the initial step of protein tertiary structure and function predictions. In this paper, we introduce CISA as a method for predicting inter-domain linker regions solely from the amino acid sequence information. The method first computes the amino acid compositional index from the protein sequence dataset of domain-linker segments and the amino acid composition. A preference profile is then generated by calculating the average compositional index values along the amino acid sequence using a sliding window. Finally, the protein sequence is segmented into intervals and a simulated annealing algorithm is employed to enhance the prediction by finding the optimal threshold value for each segment that separates domains from inter-domain linkers. The method was tested on two standard protein datasets and showed considerable improvement over the state-of-the-art domain linker prediction methods. PMID:25677918

  12. Chemical and isotopic compositions in acid residues from various meteorites

    NASA Technical Reports Server (NTRS)

    Kano, N.; Yamakoshi, K.; Matsuzaki, H.; Nogami, K.

    1993-01-01

    We are planning to carry out systematic isotopic investigations of Ru, Mg, etc., in primordial samples. The investigations will be pursued in the context of a study of the pre-history of the solar system. It is hoped that the study will yield direct evidence for processes of nucleosynthesis in the pre-solar stage and detection of extinct radioactive nuclides. In this paper, we present the results of chemical compositions of acid residues obtained from three types of meteorites: Canyon Diablo (IA), Allende (CV3), and Nuevo Mercuro (H5); and the preliminary results of Ru isotopic compositions.

  13. Jet Cooled Rotational Studies of Dipeptides

    NASA Astrophysics Data System (ADS)

    Cabezas, C.; Mata, M. Varela S.; López, J. C.; Alonso, J. L.

    2011-06-01

    Rotational spectra of Gly-Pro and Pro-Gly dipeptides have been examined with laser ablation molecular beam Fourier transform microwave (LA-MB-FTMW) spectroscopy. Three conformers for Gly-Pro and one for Pro-Gly have been unequivocally identified in the supersonic expansion by the comparison of the experimental rotational and 14N (I=1) nuclear quadrupole coupling constants with those predicted by ab initio methods. The quadrupole hyperfine structure of two 14N nuclei has been totally resolved and it allows to experimentally characterize the main intramolecular forces which stabilize the assigned conformers. The biomimetic molecule Ac-Ala-NH_2 has been also studied. The C_7 and C_5 peptide conformations (intramolecularly hydrogen-bonded seven- or five-membered cycle, respectively) have been unequivocally identified in the supersonic expansion. The ability to identify peptide conformations suggest that it soon may be possible to explore the structures of larger peptides using LA-MB-FTMW spectroscopy. J. L. Alonso, C. Pérez, M. E. Sanz, J. C. López, S. Blanco, Phys. Chem. Chem. Phys. 11,617-627 (2009)and references therein

  14. Polylactic acid (PLA)\\/banana fiber (BF) biodegradable green composites

    Microsoft Academic Search

    Yeng-Fong Shih; Chien-Chung Huang

    In this study, polylactic acid (PLA)\\/banana fiber (BF) composites were prepared by melt blending method. The BF was conjugated\\u000a onto PLA chains through the use of a coupling agent and chemical modification. Consequently, the thermal stability and mechanical\\u000a properties of the PLA were dramatically elevated through the incorporation of BF. Mechanical tests showed that the tensile\\u000a and flexural strengths of

  15. Comparing the fatty acid composition of organic and conventional milk.

    PubMed

    Ellis, K A; Innocent, G; Grove-White, D; Cripps, P; McLean, W G; Howard, C V; Mihm, M

    2006-06-01

    During a 12-mo longitudinal study, bulk-tank milk was collected each month from organic (n = 17) and conventional (n = 19) dairy farms in the United Kingdom. All milk samples were analyzed for fatty acid (FA) content, with the farming system type, herd production level, and nutritional factors affecting the FA composition investigated by use of mixed model analyses. Models were constructed for saturated fatty acids, the ratio of polyunsaturated fatty acids (PUFA) to monounsaturated fatty acids, total n-3 FA, total n-6 FA, conjugated linoleic acid, and vaccenic acid. The ratio of n-6:n-3 FA in both organic and conventional milk was also compared. Organic milk had a higher proportion of PUFA to monounsaturated fatty acids and of n-3 FA than conventional milk, and contained a consistently lower n-6:n-3 FA ratio (which is considered beneficial) compared with conventional milk. There was no difference between organic and conventional milk with respect to the proportion of conjugated linoleic acid or vaccenic acid. A number of factors other than farming system were identified which affected milk FA content including month of year, herd average milk yield, breed type, use of a total mixed ration, and access to fresh grazing. Thus, organic dairy farms in the United Kingdom produce milk with a higher PUFA content, particularly n-3 FA, throughout the year. However, knowledge of the effects of season, access to fresh grazing, or use of specific silage types could be used by producers to enhance the content of beneficial FA in milk. PMID:16702257

  16. Effects of glycyl-glutamine dipeptide supplementation on myocardial damage and cardiac function in rats after severe burn injury

    PubMed Central

    Zhang, Yong; Yan, Hong; Lv, Shang-Gun; Wang, Lin; Liang, Guang-Ping; Wan, Qian-Xue; Peng, Xi

    2013-01-01

    Glutamine decreases myocardial damage in ischemia/reperfusion injury. However, the cardioprotective effect of glutamine after burn injury remains unclear. Present study was to explore the protective effect of glycyl-glutamine dipeptide on myocardial damage in severe burn rats. Seventy-two Wistar rats were randomly divided into three groups: normal control (C), burned control (B) and glycyl-glutamine dipeptide-treated (GG) groups. B and GG groups were inflicted with 30% total body surface area of full thickness burn. The GG group was given 1.5 g/kg glycyl-glutamine dipeptide per day and the B group was given the same dose of alanine via intraperitoneal injection for 3 days. The serum CK, LDH, AST, and, blood lactic acid levels, as well as the myocardium ATP and GSH contents, were measured. The indices of cardiac contractile function and histopathological change were analyzed at 12, 24, 48, and 72 post-burn hours (PBH). The serum CK, LDH, AST and blood lactic acid levels increased, and the myocardium ATP and GSH content decreased in both burned groups. Compared with B group, the CK, LDH, AST and blood lactic acid levels reduced, myocardium ATP and GSH content increased in GG group. Moreover, the inhibition of cardiac contractile function and myocardial histopathological damage were reduced significantly in GG group. We conclude that myocardial histological structure and function were damaged significantly after burn injury, glycyl-glutamine dipeptide supplementation is beneficial to myocardial preservation by improving cardiocyte energy metabolism, increasing ATP and glutathione synthesis. PMID:23638213

  17. Relationships between fatty acid composition of body lipids and lipid mobilization in rat.

    E-print Network

    Paris-Sud XI, Université de

    of liver lipid metabolism during dietary energy res- triction. 1 ntroduction. The fatty acid composition « exogenous» fatty acids affect the fatty acid composi- tion of total liver lipids. Introducing trioleateRelationships between fatty acid composition of body lipids and lipid mobilization in rat. II

  18. Effects of Feeding Camelina (Seeds or Meal) on Milk Fatty Acid Composition and Butter Spreadability

    Microsoft Academic Search

    C. Hurtaud; J. L. Peyraud

    2007-01-01

    The nutritional and rheological properties of butter depend on the fatty acid composition of milk. There- fore, feeding oilseeds rich in unsaturated fatty acids is likely to affect butter properties. The aim of this trial was to examine to what extent feeding the linole- nic acid-rich cruciferous plant camelina can affect the fatty acid composition of dairy products and the

  19. Genetic parameters for intramuscular fatty acid composition and metabolism in pigs

    Microsoft Academic Search

    M. Ntawubizi; E. Colman; S. Janssens; K. Raes; N. Buys; S. De Smet

    2010-01-01

    The aim of this study was to estimate genetic parameters for pork intramuscular fatty acid composition and indices for desaturase and elongase activities involved in the n-3 and n-6 polyunsaturated fatty acid (PUFA) metabolism. Fatty acid composition of the longissimus muscle of 437 slaughter pigs was analysed and indices for enzyme activities were calculated from product to precursor fatty acid

  20. Modeling the Response of Fatty Acid Composition to Temperature in a Traditional Sunflower Hybrid

    Microsoft Academic Search

    Natalia G. Izquierdo; Luis A. N. Aguirrezábal; Fernando H. Andrade; Marcelo G. Cantarero

    2006-01-01

    Oil quality highly depends on its fatty acid composition. In tradi- tional sunflower (Helianthus annuus L.) hybrids, fatty acid composi- tion is affected by night temperature during grain filling. It is unknown if the increase of oleic acid concentration when night temperature increases saturates at a temperature threshold. Modeling the response of fatty acid composition to temperature could lead to

  1. A novel ceria–activated carbon composite for the catalytic ozonation of carboxylic acids

    Microsoft Academic Search

    P. C. C. Faria; J. J. M. Órfão; M. F. R. Pereira

    2008-01-01

    Ceria (Ce–O) and a novel ceria–activated carbon composite (AC0–Ce–O) were prepared and tested as catalysts in the ozonation of two selected carboxylic acids, oxalic acid and oxamic acid, at acid pH. Ce–O showed an interesting catalytic effect, especially in the ozonation of oxalic acid. A strong synergic effect was observed for the AC0–Ce–O composite in the case of oxalic acid,

  2. Amino acid compositional shifts during streptophyte transitions to terrestrial habitats.

    PubMed

    Jobson, Richard W; Qiu, Yin-Long

    2011-02-01

    Across the streptophyte lineage, which includes charophycean algae and embryophytic plants, there have been at least four independent transitions to the terrestrial habitat. One of these involved the evolution of embryophytes (bryophytes and tracheophytes) from a charophycean ancestor, while others involved the earliest branching lineages, containing the monotypic genera Mesostigma and Chlorokybus, and within the Klebsormidiales and Zygnematales lineages. To overcome heat, water stress, and increased exposure to ultraviolet radiation, which must have accompanied these transitions, adaptive mechanisms would have been required. During periods of dehydration and/or desiccation, proteomes struggle to maintain adequate cytoplasmic solute concentrations. The increased usage of charged amino acids (DEHKR) may be one way of maintaining protein hydration, while increased use of aromatic residues (FHWY) protects proteins and nucleic acids by absorbing damaging UV, with both groups of residues thought to be important for the stabilization of protein structures. To test these hypotheses we examined amino acid sequences of orthologous proteins representing both mitochondrion- and plastid-encoded proteomes across streptophytic lineages. We compared relative differences within categories of amino acid residues and found consistent patterns of amino acid compositional fluxuation in extra-membranous regions that correspond with episodes of terrestrialization: positive change in usage frequency for residues with charged side-chains, and aromatic residues of the light-capturing chloroplast proteomes. We also found a general decrease in the usage frequency of hydrophobic, aliphatic, and small residues. These results suggest that amino acid compositional shifts in extra-membrane regions of plastid and mitochondrial proteins may represent biochemical adaptations that allowed green plants to colonize the land. PMID:21153633

  3. Evaluation of fatty acid and amino acid compositions in okra (Abelmoschus esculentus) grown in different geographical locations.

    PubMed

    Sami, Rokayya; Lianzhou, Jiang; Yang, Li; Ma, Ying; Jing, Jing

    2013-01-01

    Okra has different uses as a food and a remedy in traditional medicine. Since it produces many seeds, distribution of the plant is also quite easy. Although seed oil yield is low (4.7%), since the linoleic acid composition of the seed oil is quiet high (67.5%), it can still be used as a source of (UNSAT) unsaturated fatty acids. In this study, samples of okra grown in four different locations were analyzed to measure fatty acid and amino acid compositions. The content of the lipid extraction ranged from 4.34% to 4.52% on a dry weight basis. Quantitatively, the main okra fatty acids were palmitic acid (29.18-43.26%), linoleic acid (32.22-43.07%), linolenic acid (6.79-12.34%), stearic acid (6.36-7.73%), oleic acid (4.31-6.98%), arachidic acid (ND-3.48%), margaric acid (1.44-2.16%), pentadecylic acid (0.63-0.92%), and myristic acid (0.21-0.49%). Aspartic acid, proline, and glutamic acids were the main amino acids in okra pods, while cysteine and tyrosine were the minor amino acids. Statistical methods revealed how the fatty acid and amino acid contents in okra may be affected by the sampling location. PMID:24171167

  4. Fatty acid composition and freeze-thaw resistance in lactobacilli.

    PubMed

    Gomez Zavaglia, A; Disalvo, E A; De Antoni, G L

    2000-05-01

    The fatty acid composition and freeze-thaw resistance of eight strains of thermophilic lactobacilli were studied. Seven of these contained the same polar and neutral lipids, the five major components making up 90% of the cellular fatty acid pool being 14:0, 16:0, 16:1, 18:1 and C19 cyclopropane (cyc19:0). Strain comparison by means of cluster analysis based on the fatty acid ratios using the overlap coefficient revealed two well defined clusters. One was formed by three strains of species Lactobacillus delbrueckii subsp. lactis and Lb. delbrueckii subsp. delbrueckii, the other included five strains of the species Lb. delbrueckii subsp. bulgaricus, Lb. acidophilus and Lb. helveticus. Resistance of strains with a high content of unsaturated fatty acids (66-70%) decreased with increasing cyc19:0 concentrations. In contrast, in strains with a low concentration of unsaturated fatty acids (42-49%), increasing cyc19:0 levels were associated with increased freeze-thaw resistance. PMID:10840678

  5. Structural distribution of dipeptides that are identified to be determinants of intracellular protein stability.

    PubMed

    Reddy, B V

    1996-10-01

    The dipeptides that had been previously implicated as determinants of in vivo protein stability (Guruprasad, K., Reddy, B.V.B. and Pandit, M.W., 1990. Protein Eng. 4, 155-161) have been reassessed on a latest data set and about 25% dipeptide combinations (102 dipeptides) were found to play significant role in determining the intracellular protein stability. These were classified as stabilizing dipeptides (Stb), destabilizing dipeptides (Dst) and normal dipeptides (Nor). By different theoretical approaches we have investigated the global localization of these dipeptides in a set of 303 best resolved (< or = 2.0A) non-homologous X-ray defined protein structures. The Dst dipeptides are found to be more of hydrophilic combinations where as Stb dipeptides are more of hydrophobic combinations. We observed a significant difference in overall frequency of occurrence of Stb and Dst dipeptides in different secondary structural regions. The sensitive dipeptides (Stb + Dst) are less in beta-strands and more in coils. A high frequency of occurrence of Stb are observed in the regions closer to the molecular surface compared to the Dst and Nor dipeptides. A significantly high dipole interactions are observed in the Dst dipeptides. The studies indicate that though the Dst dipeptides are more of hydrophilic nature they are localized significantly more in the buried regions of protein structures, on the other hand Stb are more of hydrophobic nature but relatively more accessible to the solvent. These dipeptides therefore increasing sensitivity of the protein to external environment, any alteration in their occurrence in the sequence could increase or decrease intracellular stability of the protein. These observations are useful to select mutations to alter intracellular stability of a given protein and therefore have implications in protein engineering. PMID:8913856

  6. Polylactic acid composites incorporating casein functionalized cellulose nanowhiskers

    PubMed Central

    2013-01-01

    Background Polylactic acid (PLA) is considered to be a sustainable alternative to petroleum-based polymers for many applications. Using cellulose fiber to reinforce PLA is of great interest recently due to its complete biodegradability and potential improvement of the mechanical performance. However, the dispersion of hydrophilic cellulose fibers in the hydrophobic polymer matrix is usually poor without using hazardous surfactants. The goal of this study was to develop homogenously dispersed cellulose nanowhisker (CNW) reinforced PLA composites using whole milk casein protein, which is an environmentally compatible dispersant. Results In this study, whole milk casein was chosen as a dispersant in the PLA-CNW system because of its potential to interact with the PLA matrix and cellulose. The affinity of casein to PLA was studied by surface plasmon resonance (SPR) imaging. CNWs were functionalized with casein and used as reinforcements to make PLA composites. Fluorescent staining of CNWs in the PLA matrix was implemented as a novel and simple way to analyze the dispersion of the reinforcements. The dispersion of CNWs in PLA was improved when casein was present. The mechanical properties of the composites were studied experimentally. Compared to pure PLA, the PLA composites had higher Young’s modulus. Casein (CS) functionalized CNW reinforced PLA (PLA-CS-CNW) at 2 wt% filler content maintained higher strain at break compared to normal CNW reinforced PLA (PLA-CNW). The Young’s modulus of PLA-CS-CNW composites was also higher than that of PLA-CNW composites at higher filler content. However, all composites exhibited lower strain at break and tensile strength at high filler content. Conclusions The presence of whole milk casein improved the dispersion of CNWs in the PLA matrix. The improved dispersion of CNWs provided higher modulus of the PLA composites at higher reinforcement loading and maintained the strain and stress at break of the composites at relatively low reinforcement loading. The affinity of the dispersant to PLA is important for the ultimate strength and stiffness of the composites. PMID:24341897

  7. Composition of Humic Acids of the Lake Baikal Sediments

    NASA Astrophysics Data System (ADS)

    Vishnyakova, O.; Chimitdorzhieva, G.; Andreeva, D.

    2012-04-01

    Humic substances are the final stage of the biogeochemical transformation of organic matter in the biosphere. Its natural compounds are found not only in soil, peat, coal, and sediments of basins. Chemical composition and properties of humic substances are determined by the functioning of the ecosystem as a whole. Therefore the study of the unique Lake Baikal sediments can provide information about their genesis, as well as the processes of organic matter transformation. For this purpose, preparations of humic acids (HA) were isolated by alkaline extraction method. The composition of HA was investigated by the elemental analyzer CHNS/O PerkinElmer Series II. Various located sediments of the Lake Baikal were the objects of the study: 1 - Chivyrkuisky Bay, 2 - Kotovo Bay, 3 - Selenga river delta near Dubinino village, 4 - Selenga river delta near Murzino village. Data on the elemental composition of HA in terms of ash-free portion show that the carbon content (CC) is of 50-53% with a maximum value in a sample 3, and minimum - in a sample 2. Such values are characteristic also for the soils with low biochemical activity. The hydrogen content is of 4,2-5,3%, a maximum value is in a sample 1. Data recalculation to the atomic percentages identified following regularities. The CC of HA is of 35-39 at. %. Hydrogen content is of 37-43 at. %. According to the content of these elements investigated substances are clearly divided into two groups: HA of the sediments of the Lake Baikal and river Selenga delta. The magnitude of the atomic ratio H/C can be seen varying degrees of condensation of the molecules of humic acids. The high atomic ratio H/C in HA of the former group indicates the predominance of aliphatic structures in the molecules. Humic acids of the later group are characterized by a low value H/C (<1), suggesting a large proportion of aromatic components in HA composition. In sediments of the Selenga river delta there is an addition of organic matter of terrigenous origin, the remains of higher plants are the most source of it. In the bays of the Lake Baikal the remains of aquatic animal organisms, other than algae, are the source of organic matter, that explain the marked differences in the HA composition. The nitrogen content in the studied HA is of 3,5-4,0 % (2 at. %), that corresponds to the lower boundary values for the soil HA. No significant differences in nitrogen content between preparations were found. HA of sediments vary widely in sulfur content: 0,5-4,6 %. Maximum sulfur content is observed in the HA of Chivyrkuy Bay, which is higher than this element content in the soil HA. Likely sources of organic matter in the sample 1 are enriched in sulfur-containing amino acids such as cystine, cysteine, methionine, which is reflected in the composition of HA. Oxygen content is about 33,8-39,1% (17-22 at. %). Data analysis of the elemental composition of humic acids of studied sediments indicates that the HA formed in subaqueous conditions of bays are slightly condensed, contain less carbon and more hydrogen, compared with HA of delta part sediments, which are more carbonized and enriched in aromatic components. Thus the last group of sediments is of mixed subaqueous and terrigenous origin.

  8. Structure-function relationship studies of PTH(1-11) analogues containing sterically hindered dipeptide mimetics.

    PubMed

    Fiori, Nereo; Caporale, Andrea; Schievano, Elisabetta; Mammi, Stefano; Geyer, Armin; Tremmel, Peter; Wittelsberger, Angela; Woznica, Iwona; Chorev, Michael; Peggion, Evaristo

    2007-08-01

    The N-terminal 1-34 fragment of parathyroid hormone (PTH) is fully active in vitro and in vivo and reproduces all biological responses characteristic of the native intact PTH. In order to develop safer and non-parenteral PTH-like bone anabolic agents, we have studied the effect of introducing conformationally constrained dipeptide mimetics into the N-terminal portion of PTH in an effort to generate miniaturized PTH-mimetics. To this end, we have synthesized and conformationally and biologically characterized PTH(1-11) analogues containing 3R-carboxy-6S-amino-7,5-bicyclic thiazolidinlactam (7,5-bTL), a rigidified dipeptide mimetic unit. The wild type sequence of PTH(1-11) is H-Ser-Val-Ser-Glu-Ile-Gln-Leu-Met-His-Asn-Leu-NH(2). The following pseudo-undecapeptides were prepared: [Ala(1), 7,5-bTL(3, 4), Nle(8), Arg(11)]hPTH(1-11)NH(2) (I); [Ala(1), 7,5-bTL(6, 7), Nle(8), Arg(11)]hPTH(1-11)NH(2) (II); [Ala(1), Nle(8), 7,5-bTL(9, 10), Arg(11)]hPTH(1-11)NH(2) (III). In aqueous solution containing 20% TFE, only analogue I exhibited the typical CD pattern of the alpha-helical conformation. NMR experiments and molecular dynamics calculations located the alpha-helical stretch in the sequence Ile(5)-His(9). The dipeptide mimetic unit 7,5-bTL induces a type III beta-turn, occupying the positions i - 1 and i of the turn. Analogue II exhibited an equilibrium between a type I beta-turn and an alpha-helix, and analogue III did not show any ordered structure. Biological tests revealed poor activity for all analogues (EC(50) > 0.1 mM). Apparently, the relative side-chain orientation of Val(2), Ile(5) and Met(8) can be critical for effective analogue-receptor interaction. Considering helicity as an essential property to obtain active PTH agonists, one must decorate the correctly positioned dipeptide mimetic azabicycloalkane scaffold with substitutions corresponding to the displaced amino acids. PMID:17617795

  9. Acid gas scrubbing by composite solvent-swollen membranes

    DOEpatents

    Matson, S.L.; Lee, E.K.L.; Friesen, D.T.; Kelly, D.J.

    1988-04-12

    A composite immobilized liquid membrane suitable for acid gas scrubbing is disclosed. The membrane is a solvent-swollen polymer and a microporous polymeric support, the solvent being selected from a class of highly polar solvents containing at least one atom selected from nitrogen, oxygen, phosphorus and sulfur, and having a boiling point of at least 100 C and a solubility parameter of from about 7.5 to about 13.5 (cal/cm[sup 3]-atm)[sup 1/2]. Such solvents are homogeneously distributed through the solvent-swollen polymer from 20% to 95% by weight. Also disclosed are methods of acid gas scrubbing of high- and low-Btu gas effluents with such solvent-swollen membranes. 3 figs.

  10. Acid gas scrubbing by composite solvent-swollen membranes

    DOEpatents

    Matson, Stephen L. (Harvard, MA); Lee, Eric K. L. (Acton, MA); Friesen, Dwayne T. (Bend, OR); Kelly, Donald J. (Bend, OR)

    1988-01-01

    A composite immobilized liquid membrane suitable for acid gas scrubbing is disclosed. The membrane is a solvent-swollen polymer and a microporous polymeric support, the solvent being selected from a class of highly polar solvents containing at least one atom selected from nitrogen, oxygen, phosphorous and sulfur, and having a boiling point of at least 100.degree. C. and a solubility parameter of from about 7.5 to about 13.5 (cal/cm.sup.3 -atm).sup.1/2. Such solvents are homogeneously distributed through the solvent-swollen polymer from 20% to 95% by weight. Also disclosed are methods of acid gas scrubbing of high- and low-Btu gas effluents with such solvent-swollen membranes.

  11. Effect of acute nitrogen dioxide exposure on the composition of fatty acid associated with phospholipids in alveolar lavage

    Microsoft Academic Search

    T. Kobayashi; T. Noguchi; M. Kikuno; K. Kubota

    1984-01-01

    In vivo exposure of rats to 10 ppm nitrogen dioxide (NOâ) for 12 h caused changes in fatty acids composition of alveolar lavage phospholipids. Among the fatty acid species, the relative ratio of palmitic acid, myristic acid and palmitoleic acid increased significantly. While the relative ratio of stearic acid, oleic acid, linoleic acid and arachidonic acid decreased significantly. Both the

  12. Conjugated linoleic acids alter the fatty acid composition and physical properties of egg yolk and albumen.

    PubMed

    Watkins, Bruce A; Feng, Shulin; Strom, Anna K; DeVitt, Amy A; Yu, Liangli; Li, Yong

    2003-11-01

    Effects of dietary conjugated linoleic acids (CLAs) and docosahexaenoic acid (DHA) on the fatty acid composition of different egg compartments after storage were studied. Four dietary treatments [supplemented with safflower oil (SAFF, control group), DHA, CLAs plus DHA (CAD), and CLAs alone] were administered to Single Comb White Leghorn (SCWL) laying hens. Eggs from the different treatment groups were collected and stored for 10 weeks at 4 degrees C before analysis. Fatty acids from the yolk (yolk granules and plasma), egg albumen, and vitelline membrane were analyzed by gas chromatography. The yolk of eggs from hens given CLAs had significantly higher amounts of saturated fatty acids, typically 16:0 and 18:0, but lower amounts of polyunsaturated fatty acids (PUFAs) compared to eggs from the control group (SAFF). CLA content was highest in the yolk and present in both neutral and polar lipids, with the greatest concentrations in neutral lipids. DHA was incorporated mainly into yolk polar lipids. Lipids in yolk plasma and granules contained similar amounts of CLAs. The fatty acid compositions of vitelline membrane and egg albumen mirrored that of the egg yolk. CLA supplementation resulted in hard and rubbery yolks when compared to hard-cooked eggs from the control group. This study showed that feeding CLAs to hens led to accumulation of the isomers in polar and neutral lipids of the egg yolk and that these isomers migrated into egg albumen. Because the sensory properties of hard-cooked eggs were negatively affected by the enrichment of a mixture of CLA isomers in this study, further research should be conducted to evaluate how the different isomers alter the properties of egg yolk and albumen so that the quality of designed eggs containing CLAs and DHA can be improved. PMID:14582988

  13. Fatty Acid\\/Expanded Graphite Composites as Phase Change Material for Latent Heat Thermal Energy Storage

    Microsoft Academic Search

    A. Sari; A. Karaipekli; K. Kaygusuz

    2008-01-01

    The fatty acid\\/expanded graphite (EG) composites as phase change material (PCM) for latent heat thermal energy storage were prepared by means of vacuum impregnation method and their thermal properties and heat charging\\/discharging characteristics were determined. In the composites, the fatty acids (capric, lauric, and myristic acids) act as a phase change latent heat storage material, and the EG serves like

  14. Fatty Acid Composition of Commercial Menhaden, Brevoortia spp., Oils, 1982 and 1983

    E-print Network

    Fatty Acid Composition of Commercial Menhaden, Brevoortia spp., Oils, 1982 and 1983 JEANNE D in the United States, has been analyzed for its fatty acid composi- tion by several investigators in recent information on fatty acid composition of menhaden oils, Ackman et al. (1981) showed that oils of this fish

  15. Fatty Acid Composition of Fish Oils UNITED STATES DEPART MENT OF THE INTERIOR

    E-print Network

    Fatty Acid Composition of Fish Oils UNITED STATES DEPART MENT OF THE INTERIOR FISH AND WILDLIFE SERVICE BUREAU OF COMMERCIAL FISHERIES #12;CHAPTER 1 Ed'" ., OG"",,. J.. IFatty Acid Composition INTRODUCTION I . of the chemical nature of fish-oil fatty acids and their dis- ~ arine life is important

  16. Three-Year Tracking of Fatty Acid Composition of Plasma Phospholipids in Healthy Children

    Microsoft Academic Search

    António Guerra; Hans Demmelmair; André Michael Toschke; Berthold Koletzko

    2007-01-01

    Objectives: The fatty acid composition of plasma phospholipids reflects the dietary fatty acid intake as well as endogenous turnover. We aimed at investigating the potential tracking of plasma phospholipid fatty acid composition in children that participated in a prospective cohort study. Methods: 26 healthy children participated in a longitudinal study on health risks and had been enrolled after birth. All

  17. Rapid and sensitive analysis of 27 underivatized free amino acids, dipeptides, and tripeptides in fruits of Siraitia grosvenorii Swingle using HILIC-UHPLC-QTRAP(®)/MS (2) combined with chemometrics methods.

    PubMed

    Zhou, Guisheng; Wang, Mengyue; Li, Yang; Peng, Ying; Li, Xiaobo

    2015-08-01

    In the present study, a new strategy based on chemical analysis and chemometrics methods was proposed for the comprehensive analysis and profiling of underivatized free amino acids (FAAs) and small peptides among various Luo-Han-Guo (LHG) samples. Firstly, the ultrasound-assisted extraction (UAE) parameters were optimized using Plackett-Burman (PB) screening and Box-Behnken designs (BBD), and the following optimal UAE conditions were obtained: ultrasound power of 280 W, extraction time of 43 min, and the solid-liquid ratio of 302 mL/g. Secondly, a rapid and sensitive analytical method was developed for simultaneous quantification of 24 FAAs and 3 active small peptides in LHG at trace levels using hydrophilic interaction ultra-performance liquid chromatography coupled with triple-quadrupole linear ion-trap tandem mass spectrometry (HILIC-UHPLC-QTRAP(®)/MS(2)). The analytical method was validated by matrix effects, linearity, LODs, LOQs, precision, repeatability, stability, and recovery. Thirdly, the proposed optimal UAE conditions and analytical methods were applied to measurement of LHG samples. It was shown that LHG was rich in essential amino acids, which were beneficial nutrient substances for human health. Finally, based on the contents of the 27 analytes, the chemometrics methods of unsupervised principal component analysis (PCA) and supervised counter propagation artificial neural network (CP-ANN) were applied to differentiate and classify the 40 batches of LHG samples from different cultivated forms, regions, and varieties. As a result, these samples were mainly clustered into three clusters, which illustrated the cultivating disparity among the samples. In summary, the presented strategy had potential for the investigation of edible plants and agricultural products containing FAAs and small peptides. PMID:25976704

  18. Fatty acid concentration, proximate composition, and mineral composition in fishbone flour of Nile Tilapia

    Microsoft Academic Search

    Maria Eugênia Petenuci; Flávia Braidoti Stevanato; Jeane Eliete; Laguila Visentainer; Makoto Matsushita; Edivaldo Egea Garcia; Nilson Evelázio de Souza; Vergilio Visentainer

    2008-01-01

    SUMMARY. Nile tilapia (Oreochormis niloticus) fishbone is a fish part with unknown composition. After elaboration of flour fishbone of tilapia it was analysede. The results in100g of flour were: moisture (14.2%), protein (40.8%), total lipids (25.3%), and ash (18.3%), and mineral (in 100g) was 2715.9mg (calcium), 1.3mg (iron), and 1132.7mg (phosphorus). A total of 22 fatty acids were detected in

  19. Effects of feeding bile acids and a bile acid sequestrant on hepatic bile acid composition in mice[S

    PubMed Central

    Zhang, Youcai; Klaassen, Curtis D.

    2010-01-01

    An improved ultra performance liquid chromatography-tandem mass spectrometry (UPLC/MS/MS) method was established for the simultaneous analysis of various bile acids (BA) and applied to investigate liver BA content in C57BL/6 mice fed 1% cholic acid (CA), 0.3% deoxycholic acid (DCA), 0.3% chenodeoxycholic acid (CDCA), 0.3% lithocholic acid (LCA), 3% ursodeoxycholic acid (UDCA), or 2% cholestyramine (resin). Results indicate that mice have a remarkable ability to maintain liver BA concentrations. The BA profiles in mouse livers were similar between CA and DCA feedings, as well as between CDCA and LCA feedings. The mRNA expression of Cytochrome P450 7a1 (Cyp7a1) was suppressed by all BA feedings, whereas Cyp7b1 was suppressed only by CA and UDCA feedings. Gender differences in liver BA composition were observed after feeding CA, DCA, CDCA, and LCA, but they were not prominent after feeding UDCA. Sulfation of CA and CDCA was found at the 7-OH position, and it was increased by feeding CA or CDCA more in male than female mice. In contrast, sulfation of LCA and taurolithocholic acid (TLCA) was female-predominant, and it was increased by feeding UDCA and LCA. In summary, the present systematic study on BA metabolism in mice will aid in interpreting BA-mediated gene regulation and hepatotoxicity. PMID:20671298

  20. Effects of dietary ?-linolenic acid deficiency during pregnancy and lactation on lipid fatty acid composition of liver

    E-print Network

    Paris-Sud XI, Université de

    fatty acids (n-3 PUFA) in liver and serum lipids, and particularly of 22 :6 n-3. This declineEffects of dietary ?-linolenic acid deficiency during pregnancy and lactation on lipid fatty acid composition of liver and serum in the rat Ph. GUESNET G. PASCAL G. DURAND Station de Recherches de

  1. Muramyl dipeptide and its derivatives: peptide adjuvant in immunological disorders and cancer therapy

    PubMed Central

    Ogawa, Chikako; Liu, Yuen-Joyce; Kobayashi, Koichi S.

    2011-01-01

    Muramyl dipeptide (MDP) is a synthetic immunoreactive peptide consisting of N-acetyl muramic acid attached to a short amino acid chain of L-Ala-D-isoGln. It was first identified in bacterial cell wall peptidoglycan as an active component in Freund’s complete adjuvant. In the cell, MDP is detected by NOD2, a cytoplasmic receptor belonging to the human innate immune system. NOD2 mutations are frequently observed in patients with Crohn’s disease, an autoimmune disorder, suggesting the significance of the MDP-NOD2 pathway in activating immunity. For this reason, structural modifications of MDP and its derivatives have been extensively studied in an attempt to increase adjuvant activity and boost the immune response effectively for clinical use in the treatment of cancer and other diseases. This review summarizes the synthetic chemistry of MDP and its derivatives and discusses their pharmacological action and stereoselective synthesis. PMID:22180736

  2. Nucleic acid compositions with scissile linkage useful for detecting nucleic acid sequences

    SciTech Connect

    Duck, P.; Bender, R.; Crosby, W.; Robertson, J.G.

    1989-10-24

    This patent describes a composition. It comprises the structure: S-L(NA{sub 1}-S-NA{sub 2}){sub n}M. NA{sub 1} and NA{sub 2} are nucleic acid sequences; -S- is a scissile linkage which is capable of being cleaved or disrupted without cleaving or disrupting the nuclei acid sequences of NA{sub 1} or NA{sub 2} or of a target nuclei acid sequence capable of hybridizing to the NA{sub 1} and NA{sub 2} sequences, or to the NA{sub 1} and NA{sub 2} sequences and the scissile linkage of the composition, wherein if the scissile linkage is a nuclei acid sequence it is RNA when both NA{sub 1} and NA{sub 2} are DNA sequences, or the scissile linkage is DNA when both NA{sub 1} and NA{sub 2} are RNA sequences; and n is an integer from 1 to 4. The solid lines represent chemical bonds; X is a solid support; L is a chemical entity which links NA{sub 1} to the solid support; and M is a marker.

  3. Adansonian Analysis and Deoxyribonucleic Acid Base Composition of Serratia marcescens

    PubMed Central

    Colwell, R. R.; Mandel, M.

    1965-01-01

    Colwell, R. R. (Georgetown University, Washington, D.C.), and M. Mandel. Adansonian analysis and deoxyribonucleic acid base composition of Serratia marcescens. J. Bacteriol. 89:454–461. 1965.—A total of 33 strains of Serratia marcescens were subjected to Adansonian analysis for which more than 200 coded features for each of the organisms were included. In addition, the base composition [expressed as moles per cent guanine + cytosine (G + C)] of the deoxyribonucleic acid (DNA) prepared from each of the strains was determined. Except for four strains which were intermediate between Serratia and the Hafnia and Aerobacter group C of Edwards and Ewing, the S. marcescens species group proved to be extremely homogeneous, and the different strains showed high affinities for each other (mean similarity, ¯S = 77%). The G + C ratio of the DNA from the Serratia strains ranged from 56.2 to 58.4% G + C. Many species names have been listed for the genus, but only a single clustering of the strains was obtained at the species level, for which the species name S. marcescens was retained. S. kiliensis, S. indica, S. plymuthica, and S. marinorubra could not be distinguished from S. marcescens; it was concluded, therefore, that there is only a single species in the genus. The variety designation kiliensis does not appear to be valid, since no subspecies clustering of strains with negative Voges-Proskauer reactions could be detected. The characteristics of the species are listed, and a description of S. marcescens is presented. PMID:14255714

  4. Incorporation of fatty acids by concanavalin A-stimulated lymphocytes and the effect on fatty acid composition and membrane fluidity.

    PubMed Central

    Calder, P C; Yaqoob, P; Harvey, D J; Watts, A; Newsholme, E A

    1994-01-01

    The fatty acid compositions of the neutral lipid and phospholipid fractions of rat lymph node lymphocytes were characterized. Stimulation of rat lymphocytes with the T-cell mitogen concanavalin A resulted in significant changes in the fatty acid composition of both neutral lipids and phospholipids (a decrease in the proportions of stearic, linoleic and arachidonic acids and an increase in the proportion of oleic acid). Membrane fluidity was measured using nitroxide spin-label e.s.r., and increased during culture with concanavalin A. Culturing the lymphocytes in the absence of mitogen did not affect fatty acid composition or membrane fluidity. The uptake and fate of palmitic, oleic, linoleic and arachidonic acids were studied in detail; there was a time-dependent incorporation of each fatty acid into all lipid classes but each fatty acid had a characteristic fate. Palmitic and arachidonic acids were incorporated principally into phospholipids whereas oleic and linoleic acids were incorporated in similar proportions into phospholipids and triacylglycerols. Oleic acid was incorporated mainly into phosphatidylcholine, palmitic and linoleic acids were incorporated equally into phosphatidylcholine and phosphatidylethanolamine, and arachidonic acid was incorporated mainly into phosphatidylethanolamine. Supplementation of the culture medium with particular fatty acids (myristic, palmitic, stearic, oleic, linoleic, alpha-linolenic, arachidonic, eicosapentaenoic or docosahexaenoic acid) led to enrichment of that fatty acid in both neutral lipids and phospholipids. This generated lymphocytes with phospholipids differing in saturated/unsaturated fatty acid ratio, degree of polyunsaturation, index of unsaturation and n - 6/n - 3 ratio. This method allowed the introduction into lymphocyte phospholipids of fatty acids not normally present (e.g. alpha-linolenic) or usually present in low proportions (eicosapentaenoic and docosahexaenoic). These three n - 3 polyunsaturated fatty acids replaced arachidonic acid in lymphocyte phospholipids. Fatty acid incorporation led to an alteration in lymphocyte membrane fluidity: palmitic and stearic acids decreased fluidity whereas the unsaturated fatty acids increased fluidity. It is proposed that the changes in lymphocyte phospholipid fatty acid composition and membrane fluidity brought about by culture in the presence of polyunsaturated fatty acids are responsible for the inhibition of lymphocyte functions caused by these fatty acids. PMID:8002957

  5. Effect of diet on plasma acid-base composition in normal humans

    Microsoft Academic Search

    Ira Kurtz; Terry Maher; Henry N Hulter; Morris Schambelan; Anthony Sebastian

    1983-01-01

    Effect of diet on plasma acid-base composition in normal humans. Steady-state plasma and urine acid-base composition was assessed in 19 studies of 16 normal subjects who ingested constant amounts of one of three diets that resulted in different rates of endogenous noncarbonic acid production (EAP) within the normal range. Renal net acid excretion (NAE) was used to quantify EAP since

  6. SCMHBP: prediction and analysis of heme binding proteins using propensity scores of dipeptides

    PubMed Central

    2014-01-01

    Background Heme binding proteins (HBPs) are metalloproteins that contain a heme ligand (an iron-porphyrin complex) as the prosthetic group. Several computational methods have been proposed to predict heme binding residues and thereby to understand the interactions between heme and its host proteins. However, few in silico methods for identifying HBPs have been proposed. Results This work proposes a scoring card method (SCM) based method (named SCMHBP) for predicting and analyzing HBPs from sequences. A balanced dataset of 747 HBPs (selected using a Gene Ontology term GO:0020037) and 747 non-HBPs (selected from 91,414 putative non-HBPs) with an identity of 25% was firstly established. Consequently, a set of scores that quantified the propensity of amino acids and dipeptides to be HBPs is estimated using SCM to maximize the predictive accuracy of SCMHBP. Finally, the informative physicochemical properties of 20 amino acids are identified by utilizing the estimated propensity scores to be used to categorize HBPs. The training and mean test accuracies of SCMHBP applied to three independent test datasets are 85.90% and 71.57%, respectively. SCMHBP performs well relative to comparison with such methods as support vector machine (SVM), decision tree J48, and Bayes classifiers. The putative non-HBPs with high sequence propensity scores are potential HBPs, which can be further validated by experimental confirmation. The propensity scores of individual amino acids and dipeptides are examined to elucidate the interactions between heme and its host proteins. The following characteristics of HBPs are derived from the propensity scores: 1) aromatic side chains are important to the effectiveness of specific HBP functions; 2) a hydrophobic environment is important in the interaction between heme and binding sites; and 3) the whole HBP has low flexibility whereas the heme binding residues are relatively flexible. Conclusions SCMHBP yields knowledge that improves our understanding of HBPs rather than merely improves the prediction accuracy in predicting HBPs. PMID:25522279

  7. Citric Acid-based Hydroxyapatite Composite Scaffolds Enhance Calvarial Regeneration

    PubMed Central

    Sun, Dawei; Chen, Yuhui; Tran, Richard T.; Xu, Song; Xie, Denghui; Jia, Chunhong; Wang, Yuchen; Guo, Ying; Zhang, Zhongmin; Guo, Jinshan; Yang, Jian; Jin, Dadi; Bai, Xiaochun

    2014-01-01

    Citric acid-based polymer/hydroxyapatite composites (CABP-HAs) are a novel class of biomimetic composites that have recently attracted significant attention in tissue engineering. The objective of this study was to compare the efficacy of using two different CABP-HAs, poly (1,8-octanediol citrate)-click-HA (POC-Click-HA) and crosslinked urethane-doped polyester-HA (CUPE-HA) as an alternative to autologous tissue grafts in the repair of skeletal defects. CABP-HA disc-shaped scaffolds (65 wt.-% HA with 70% porosity) were used as bare implants without the addition of growth factors or cells to renovate 4?mm diameter rat calvarial defects (n = 72, n = 18 per group). Defects were either left empty (negative control group), or treated with CUPE-HA scaffolds, POC-Click-HA scaffolds, or autologous bone grafts (AB group). Radiological and histological data showed a significant enhancement of osteogenesis in defects treated with CUPE-HA scaffolds when compared to POC-Click-HA scaffolds. Both, POC-Click-HA and CUPE-HA scaffolds, resulted in enhanced bone mineral density, trabecular thickness, and angiogenesis when compared to the control groups at 1, 3, and 6 months post-trauma. These results show the potential of CABP-HA bare implants as biocompatible, osteogenic, and off-shelf-available options in the repair of orthopedic defects. PMID:25372769

  8. Carbohydrate, Organic Acid, and Amino Acid Composition of Bacteroids and Cytosol from Soybean Nodules 1

    PubMed Central

    Streeter, John G.

    1987-01-01

    Metabolites in Bradyrhizobium japonicum bacteroids and in Glycine max (L.) Merr. cytosol from root nodules were analyzed using an isolation technique which makes it possible to estimate and correct for changes in concentration which may occur during bacteroid isolation. Bacteroid and cytosol extracts were fractionated on ion-exchange columns and were analyzed for carbohydrate composition using gas-liquid chromatography and for organic acid and amino acid composition using high performance liquid chromatography. Analysis of organic acids in plant tissues as the phenacyl derivatives is reported for the first time and this approach revealed the presence of several unknown organic acids in nodules. The time required for separation of bacteroids and cytosol was varied, and significant change in concentration of individual compounds during the separation of the two fractions was estimated by calculating the regression of concentration on time. When a statistically significant slope was found, the true concentration was estimated by extrapolating the regression line to time zero. Of 78 concentration estimates made, there was a statistically significant (5% level) change in concentration during sample preparation for only five metabolites: glucose, sucrose, and succinate in the cytosol and d-pinitol and serine in bacteroids. On a mass basis, the major compounds in bacteroids were (descending order of concentration): myo-inositol, d-chiro-inositol, ?,?-trehalose, sucrose, aspartate, glutamate, d-pinitol, arginine, malonate, and glucose. On a proportional basis (concentration in bacteroid as percent of concentration in bacteroid + cytosol fractions), the major compounds were: ?-aminoadipate (94), trehalose (66), lysine (58), and arginine (46). The results indicate that metabolite concentrations in bacteroids can be reliably determined. PMID:16665774

  9. Distribution and enantiomeric composition of amino acids in the Murchison meteorite

    NASA Technical Reports Server (NTRS)

    Engel, M. H.; Nagy, B.

    1982-01-01

    Studies of the amino acid contents and enantiomeric compositions of a single stone from the Murchison meteorite are reported. Water-extracted and 6M HCl-extracted samples from the meteorite interior of meteorite fragments were analyzed by gas chromatography and combined gas chromatography-chemical ionization mass spectrometry. Examination of the D/L ratios of glutamic acid, aspartic acid, proline, leucine and alanine reveals those amino acids extractable by water to be partially racemized, whereas the acid-extracted amino acids were less racemized. The amino acid composition of the stone is similar to those previously reported, including the absence of serine, threonine, tyrosine phenylalanine and methionine and the presence of unusual amino acids including such as isovaline, alpha-aminoisobutyric acid and pseudoleucine. It is concluded that the most likely mechanism accounting for the occurrence of nonracemic amino acid mixtures in the Murchison meteorite is by extraterrestrial stereoselective synthesis or decomposition reactions.

  10. Synthetic and enzyme inhibition studies of pepstatin analogues containing hydroxyethylene and ketomethylene dipeptide isosteres.

    PubMed

    Holladay, M W; Salituro, F G; Rich, D H

    1987-02-01

    Synthetic details for the preparation of a series of hydroxyethylene and ketomethylene dipeptide isosteres with control of stereochemistry at C(2) are described. Incorporation of the isosteres into peptide sequences derived from pepstatin afforded potent inhibitors of the aspartic protease porcine pepsin. When Leu-OH-Ala or Leu-OH-Phe was substituted for statine [3S,4S)-4-amino-3-hydroxy-6-methylheptanoic acid), inhibitors equipotent to the parent compound were obtained, whereas Leu-OH-Gly was a much less effective replacement for statine. A similar trend was evident in the corresponding ketones. The finding that structural features for good substrates do not closely parallel those for good inhibitors is discussed. PMID:3100803

  11. Texture of Butter from Cows with Different Milk Fatty Acid Compositions1

    Microsoft Academic Search

    G. Bobe; E. G. Hammond; A. E. Freeman; G. L. Lindberg; D. C. Beitz

    2003-01-01

    Milk fatty acid composition and textural properties of butter are known to be affected by the cows' diets. We examined the phenotypic variation in milk fatty acid composition among cows fed the same diet to see if the variation was sufficient to produce butter with different textural properties. Ten cows were selected that tested higher (n = 5) or lower

  12. In vivo milk digestion in the calf abomasum. III. Amino acid compositions of the digesta leaving

    E-print Network

    Paris-Sud XI, Université de

    In vivo milk digestion in the calf abomasum. III. Amino acid compositions of the digesta leaving different test meals : whole milk, skim milk, 3 % whole casein solution, 3 % whole casein in simulated milk the first 10 min following the ingestion of whole or skim milk, the amino acid composition of the sediment

  13. Effect of feeding different fat supplements on the fatty acid composition of goat milk

    Microsoft Academic Search

    S. K. Gulati; E. B. Byers; Y. G. Byers; J. R. Ashes; T. W. Scott

    1997-01-01

    The effect of feeding dietary fat supplements on the fatty acid composition of goat milk was examined. Inclusion of canola and soybean (8020; ww) oilseed supplement protected from ruminal hydrogenation, significantly increased the proportion of C18:1 (oleic acid), C18:2 (linoleic acid) and decreased the proportion of C16:0 (palmitic acid) and C14:0 (myristic acid), while there was a small increase in

  14. Composition of phenolic acids in sea buckthorn ( Hippophae rhamnoides L.) berries

    Microsoft Academic Search

    R. Zadernowski; M. Naczk; S. Czaplicki; M. Rubinskiene; M. Sza?kiewicz

    2005-01-01

    The composition of phenolic acids in several varieties of sea buckthorn berries was determined by GC and MS. In six cultivars\\u000a the total content of phenolic acids ranged from 3570282 to 4439405 mg per kg of berries, on a dry basis. Seventeen phenolic\\u000a acids were tentatively identified in the berries. Salicylic acid was the principal phenolic acid in sea buckthorn

  15. Heterocycle-substituted proline dipeptides as potent VLA4 antagonists

    Microsoft Academic Search

    Thomas S. Reger; Jasmine Zunic; Nicholas Stock; Bowei Wang; Nicholas D. Smith; Benito Munoz; Mitchell D. Green; Michael F. Gardner; Joyce P. James; Weichao Chen; Kenneth Alves; Qian Si; Kelly M. Treonze; Russell B. Lingham; Richard A. Mumford

    2010-01-01

    A variety of N-linked tertiary amines and heteroarylamines were examined at the 4-position of sulfonylated proline dipeptides in order to improve VLA-4 receptor off-rates and overcome the issue of CYP3A4 time-dependent inhibition of ester prodrugs. A tight-binding inhibitor 5j with a long off-rate provided sustained receptor occupancy despite poor oral pharmacokinetics.

  16. Ethanol-induced alterations in lipid composition of Saccharomyces cerevisiae in the presence of exogenous fatty acid

    Microsoft Academic Search

    Haruhiko Mizoguchi; Shodo Hara

    1997-01-01

    Ethanol-induced alterations in the lipid composition of Saccharomyces cerevisiae grown in the presence of exogenous fatty acids were studied. The addition of both palmitic acid and ethanol (4–8%) to the basal medium resulted in a striking increase in the palmitic acid content and decreases in the content of myristoleic, palmitoleic, and oleic acids in the phospholipid fatty acid composition, compared

  17. Statine-containing dipeptide and tripeptide inhibitors of human renin.

    PubMed

    Kokubu, T; Hiwada, K; Nagae, A; Murakami, E; Morisawa, Y; Yabe, Y; Koike, H; Iijima, Y

    1986-06-01

    Dipeptide and tripeptide derivatives containing a statine residue were synthesized as inhibitors of human renin. ES-305, bis[(1-naphthyl)methyl]acetyl(BNMA)-histidyl-statine 2(S)-methylbutylamide was found to be a highly potent inhibitor of human renin with a Ki value of 1.7 X 10(-9) M. Dipeptide derivatives with the BNMA group at the N-terminal (BNMA-Val-Sta-isoleucinol [ES-313], BNMA-Leu-Sta-isoleucinol [ES-316], and BNMA-Nle-Sta-isoleucinol [ES-317]) had potencies against human renin that were similar to the potency of ES-305. All these dipeptide derivatives competitively inhibited human renin. The inhibitors were also potent against monkey renin but were less effective against renins from pig, goat, dog, rabbit, and rat. ES-305 had little effect on cathepsin D and pepsin at the concentration of 10(-5) M. The other derivatives showed detectable inhibition of cathepsin D (IC50, 10(-6) - 10(-7) M) and pepsin (10(-5) - 10(-6) M). All the compounds had little or no effect on trypsin, chymotrypsin, angiotensin converting enzyme, and urinary kallikrein at the concentration of 10(-5) M. Our results indicate that ES-305 is a highly potent and specific inhibitor of human renin. This compound is superior to other, previously described statine-containing renin inhibitors with respect to molecular size and enzyme specificity. PMID:3087874

  18. Energetics of Cyclic Dipeptide Crystal Packing and Solvation

    PubMed Central

    Brady, G. Patrick; Sharp, Kim A.

    1997-01-01

    Calculations of the thermodynamics of transfer of the cyclic alanine-alanine (cAA) and glycine-glycine (cGG) dipeptides between the gas, water, and crystal phases were carried out using a combination of molecular mechanics, normal mode analysis, and continuum electrostatics. The experimental gas-to-water solvation free energy and the enthalpy of gas-to-crystal transfer of cGG are accurately reproduced by the calculations. The enthalpies of cGG and cAA crystal-to-water transfer are also close to the experimental values. A combination of experimental data and normal mode analysis of cGG provides an accurate estimate of the association entropy penalty (loss of rotational and translational entropy and gain in vibrational entropy) for “binding” in the crystalline phase of -14.1 cal/mol/K. This is a smaller number than most previous theoretical estimates, but it is similar to previous experimental estimates. Calculated entropies of the crystal phase under-estimate the experimental entropy by about 15 cal/mol/K because of neglect of longe-range lattice motions. Comparison of the intermolecular interactions in the crystals of cGG and cAA provides a possible explanation of the puzzling decrease in enthalpy, with increasing hydrophobicity seen previously for both cyclic dipeptide dissolution and protein unfolding. This decrease arises from a favorable long-range electrostatic interaction between dipeptide molecules in the crystals, which is attenuated by the more hydrophobic side chains. PMID:9017216

  19. Amino acid composition of early stages of cephalopods and effect of amino acid dietary treatments on Octopus vulgaris paralarvae

    Microsoft Academic Search

    R. Villanueva; J. Riba; C. Ru??z-Capillas; A. V. González; M. Baeta

    2004-01-01

    During the present study, we aimed to provide a first look at the amino acid composition of the early stages of cephalopods and follow possible effects of certain dietary treatments. Amino acid profiles of cuttlefish Sepia officinalis, squid Loligo vulgaris and octopus, Octopus vulgaris hatchlings and wild juveniles of L. vulgaris and O. vulgaris were analysed. Cephalopod hatchlings showed high

  20. Relationships between dietary fatty acid composition and either melting point or fatty acid profile of adipose tissue in broilers

    Microsoft Academic Search

    F. J. Bavelaar; A. C. Beynen

    2003-01-01

    Data on the fatty acid composition of the diet and that of the adipose tissue in broilers were collected from the literature. The linear regression between the dietary and the adipose tissue unsaturated to saturated fatty acids ratio (U\\/S ratio) was calculated because the U\\/S ratio of adipose tissue fat determines its melting point, which is an indicator of the

  1. The changes of fatty acid and amino acid compositions in sea bream ( Sparus aurata) during irradiation process

    NASA Astrophysics Data System (ADS)

    Erkan, Nuray; Özden, Özkan

    2007-10-01

    Aqua cultured fish (sea bream) were irradiated by Cobalt-60 at commercial irradiation facility at dose of 2.5 and 5 kGy at 2-4 °C. The proximate composition, fatty acid and amino acid composition changes of irradiated aqua cultured sea bream ( Sparus aurata) of Aegean Sea were investigated. Total saturated (28.01%) and total monounsaturated (28.42%) fatty acid contents of non-irradiated decreased content of 27.69-27.97% for 2.5 kGy irradiated groups and increased content of 28.33-28.56% for 5 kGy irradiated groups after irradiation process. Total polyunsaturated fatty acid content for irradiated samples was lower than that of non-irradiated samples. Aspartic acid, glutamic acid, serine, glycine, arginine, alanine, tyrosine, cystine, tryptophan, lysine and proline contents for 2.5 and 5 kGy irradiated sea bream are significantly different ( p<0.05).

  2. Soil amino acid composition quantified by acid hydrolysis and anion chromatography-pulsed amperometry.

    PubMed

    Martens, Dean A; Loeffelmann, Kevin L

    2003-10-22

    Soil organic N accounts for 95-98% of the total soil N content with amino acids (AAs) and amino sugars (ASs) identified as the major soil organic N compounds, but traditional 6 M HCl with reflux or sealed digestions for 24 h and various detection systems have accounted for only 30-40% of soil total N content as AA-N. This study compared traditional HCl extraction methodology with methanesulfonic acid (MSA) hydrolysis and nonderivatized AA and AS quantification by ion chromatography with pulsed amperometric detection for determination of the AA composition of plant litter and soils. MSA (4 M) gave AA-N recovery comparable to or better than 6 M HCl for plant AA digestions (16 h, 121 degrees C, 104 kPa). Use of 4 M MSA (0.5-1.5 h, 136 degrees C, 112 kPa) increased the total recovery of organic N as AAs, ASs, and NH(4)(+) by 46% from soils (n = 22) compared with 6 M HCl (12 h, 110 degrees C, reflux) with a MSA recovery rate of 85.6% of the total N content (n = 22 soils). The shorter MSA soil digestions (0.5-1.5 h) suggested that the majority of soil organic N was not present as protein forms found in plant litter analysis (16 h of digestion). MSA ion chromatographic analysis for soil AA/AS composition is a robust nonderivatization method requiring little sample preparation that can distinguish between small changes in soil AA composition during one growing season due to vegetation and tillage managements. PMID:14558773

  3. Preparation and characterization of polyaniline\\/manganese dioxide composites via oxidative polymerization: Effect of acids

    Microsoft Academic Search

    Ali H. Gemeay; Ikhlas A. Mansour; Rehab G. El-Sharkawy; Ahmed B. Zaki

    2005-01-01

    Polyaniline\\/manganese dioxide (PANI\\/MnO2) composites have been chemically prepared by oxidative polymerization of aniline in acidic medium containing MnO2 as an oxidant. The acids used were; H2SO4, HNO3, HCl, and H3PO4 The prepared composites were characterized by SEM, elemental analysis, FT-IR, XRD, TGA, and magnetic susceptibility. XRD measurements of the composites revealed that the crystal structure of incorporated MnO2 undergone a

  4. Hydrofluoric acid-resistant composite window and method for its fabrication

    DOEpatents

    Ostenak, C.A.; Mackay, H.A.

    1985-07-18

    A hydrofluoric acid-resistant composite window and method for its fabrication are disclosed. The composite window comprises a window having first and second sides. The first side is oriented towards an environment containing hydrofluoric acid. An adhesive is applied to the first side. A layer of transparent hydrofluoric acid-resistant material, such as Mylar, is applied to the adhesive and completely covers the first side. The adhesive is then cured.

  5. Development and Material Properties of Chitosan and Phosphomolybdic Acid-based Composites

    Microsoft Academic Search

    A. H. Bhat; Irshad-Ul-Haq Bhat; H. P. S. Abdul Khalil; R. K. Mishra; M. Datt; Ajit K. Banthia

    2011-01-01

    This work reports the development and characterization of chitosan\\/ phosphomolybdic acid-based composite membranes. The prepared composite membranes were characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), differential scanning calorimetry (DSC), tensile strength test, and thermogravimetric analysis (TGA). FTIR spectroscopy indicated the proper molecular interactions between chitosan and PMA. XRD spectroscopy indicated the semi crystalline nature of the composite

  6. Fabrication and Mechanical Properties of Completely Biodegradable Hemp Fiber Reinforced Polylactic Acid Composites

    Microsoft Academic Search

    Ruihua Hu; Jae-Kyoo Lim

    2007-01-01

    Biodegradable composite materials can be produced by the combination of biodegradable polymers and natural fibers. In this study, a new biodegradable composite of hemp fiber reinforced polylactic acid (PLA) was fabricated using the hot press method. Mechanical properties of composites with different fiber volume fractions were tested. The optimum fiber content was determined according to the test results. Effects of

  7. Amino Acids Composition of Teucrium Nutlet Proteins and their Systematic Significance

    PubMed Central

    JUAN, R.; PASTOR, J.; MILLÁN, F.; ALAIZ, M.; VIOQUE, J.

    2004-01-01

    • Background and Aims Plant species are considered as a good source of dietary proteins, although the nutritional quality of proteins depends on their amino acid composition. In this work the protein content and amino acid composition of nutlets of 21 Teucrium taxa (Lamiaceae) from Spain were analysed and their nutritional quality was compared with the minimum values established by the Food and Agriculture Organization of the United Nations (FAO). In addition, the amino acid composition was evaluated as a chemical character to clarify the taxonomic complexity in this genus. • Methods Amino acid content of nutlets was determined after derivatization with diethyl ethoxymethylenemalonate by high-performance liquid chromatography. Previously, nutlets samples were hydrolysed and incubated in an oven at 110 °C for 24 h. • Key Results The protein content was variable, ranging from 6·4 % in T. dunense to 43·8 % in T. algarbiense. According to the FAO values all taxa contain satisfactory amounts of leucine, threonine and valine and are deficient in lysine. The similarity analysis of Teucrium taxa using amino acid composition data did not clearly reflect the infrageneric classification of this genus. • Conclusions Annual species, such as T. spinosum, T. aristatum and T. resupinatum showed a better balanced amino acid composition. The dendrogram partly matched with the karyological complexity of Teucrium. No correlation between amino acid composition and habitat has been observed, showing that Teucrium nutlet amino acid composition may not be strongly influenced by the environment. PMID:15329333

  8. The fatty acid, amino acid, and mineral composition of Egyptian goose meat as affected by season, gender, and portion.

    PubMed

    Geldenhuys, Greta; Hoffman, Louwrens C; Muller, Nina

    2015-05-01

    With the current absence of scientific information on the nutritive aspects it is essential to investigate the fatty acid, mineral, and amino acid composition of Egyptian geese as well as the factors of influence. The forage vs. grain based diets of Egyptian geese during certain periods of the yr leads to variation in the content of the key fatty acids such as oleic acid, linoleic acid, and ?-linolenic acid. The differences in these fatty acids results in variation between the n-6/n-3 ratios of the seasons; the portions from winter (July) are within the recommendations (ratio <5) and those from summer (November) not. This study indicates that Egyptian goose meat does not only vary in nutritional composition but season may also have a substantial effect on the flavor profile and ultimate uniformity of the meat. The season and portion effects were, however, interlinked but the general tendency shows that the portions, especially the breast and thigh do differ concerning the major fatty acids. No substantial differences were found in the mineral composition of the breast portion on account of season and gender; however there were some variation in certain amino acids such as lysine and arginine due to season/diet. This research provides essential information that should be considered not only regarding the everyday consumption of Egyptian goose meat but the potential utilization and ultimate consistency of this meat product. PMID:25810407

  9. Manipulating the fatty acid composition of muscle and adipose tissue in beef cattle

    Microsoft Academic Search

    Nigel D. Scollan; Nag-Jin Choi; Esra Kurt; Alan V. Fisher; Mike Enser; Jeff D. Wood

    2001-01-01

    Enhancing the n-3 polyunsaturated fatty acid (PUFA) content of beef is important in view of the generally saturated nature of fatty acids in ruminant meats and the negative effect this can have on human health. This study examined the effects of different sources of dietary n-3 PUFA on the performance of steers and the fatty acid composition of m. longissimus

  10. Fatty acid composition including cis-9, trans-11 CLA of cooked ground lamb

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Little information is available on effect of cooking on beneficial fatty acids such as conjugated linoleic acid (CLA) and n-3 polyunsaturated fatty acids (PUFA). The objective of this study was to examine impact of cooking on the FA composition of ground lamb of two different muscles. Samples were p...

  11. EFFECTS OF DIFFERENT HARVEST TIME AND SULFUR FERTILIZATION ON AMINO ACID COMPOSITION OF LENTIL

    Microsoft Academic Search

    Yucel Kesli; M. Sait Adak

    2012-01-01

    The effects of sulfur (S) fertilization and harvest time on amino acid composition of seeds of field-grown lentil (Lens culinaris Medik.) at two different sites were studied. The aim of this study was to determine amino acid content of seed protein and to increase low levels of sulfur amino acids and trytophan in lentil seeds, which are major components for

  12. Hydrolysis of protein and model dipeptide substrated by attached and nonattached marine Pseudomonas sp. strain NCIMB 2021

    SciTech Connect

    Griffith, P.C.; Fletcher, M. (Univ. of Maryland System, Baltimore (USA))

    1991-08-01

    Rates of substrate hydrolysis by nonattached bacteria and by bacteria attached to particles derived from marine diatom frustules were estimated by using two substrates, a dipeptide analog and a protein. Adsorption of the two substrates onto the particles was also evaluated. Methyl-coumarinyl-amide-leucine (MCA-leucine) was used to estimate hydrolysis of dipeptides by measuring an increase in fluorescence as MCA-leucine was hydrolyzed to leucine and the fluorochrome methylcoumarin. To examine hydrolysis of a larger molecule, was prepared a radiolabeled protein by {sup 14}C-methylation of bovine serum albumin. The rate of protein hydrolysis in samples of particle-attached or nonattached bacteria was estimated by precipitating all nonhydrolyzed protein with cold trichloroacetic acid and then determining the trichloroacetic acid-soluble radiolabeled material, which represented methyl-{sup 14}C-peptides and -amino acids. About 25% of the MCA-leucine adsorbed to the particles. MCA-leucine was hydrolyzed faster by nonattached than attached bacteria, which was probably related to its tendency to remain dissolved in the liquid phase. In contrast, almost 100% of the labeled protein adsorbed to the particles. Accordingly, protein was much less available to nonattached bacteria but was rapidly hydrolyzed by attached bacteria.

  13. Protonated Dipeptide Losses from b 5 and b 4 Ions of Side Chain Hydroxyl Group Containing Pentapeptides

    NASA Astrophysics Data System (ADS)

    Atik, A. Emin; Yalcin, Talat

    2013-10-01

    In this study, C-terminal protonated dipeptide eliminations were reported for both b 5 and b 4 ions of side chain hydroxyl group (-OH) containing pentapeptides. The study utilized the model C-terminal amidated pentapeptides having sequences of XGGFL and AXVYI, where X represents serine (S), threonine (T), glutamic acid (E), aspartic acid (D), or tyrosine (Y) residue. Upon low-energy collision-induced dissociation (CID) of XGGFL (where X = S, T, E, D, and Y) model peptide series, the ions at m/z 279 and 223 were observed as common fragments in all b 5 and b 4 ion (except b 4 ion of YGGFL) mass spectra, respectively. By contrast, peptides, namely SMeGGFL-NH2 and EOMeGGFL-NH2, did not show either the ion at m/z 279 or the ion at m/z 223. It is shown that the side chain hydroxyl group is required for the possible mechanism to take place that furnishes the protonated dipeptide loss from b 5 and b 4 ions. In addition, the ions at m/z 295 and 281 were detected as common fragments in all b 5 and b 4 ion (except b 4 ion of AYVYI) mass spectra, respectively, for AXVYI model peptide series. The MS4 experiments exhibited that the fragment ions at m/z 279, 223, 295, and 281 entirely reflect the same fragmentation behavior of [M + H]+ ion generated from commercial dipeptides FL-OH, GF-OH, YI-OH, and VY-OH. These novel eliminations reported here for b 5 and b 4 ions can be useful in assigning the correct and reliable peptide sequences for high-throughput proteomic studies.

  14. Efficacy of Parenteral Nutrition Supplemented With Glutamine Dipeptide to Decrease Hospital Infections in Critically Ill Surgical Patients

    PubMed Central

    Estívariz, Concepción F.; Griffith, Daniel P.; Luo, Menghua; Szeszycki, Elaina E.; Bazargan, Niloofar; Dave, Nisha; Daignault, Nicole M.; Bergman, Glen F.; McNally, Therese; Battey, Cindy H.; Furr, Celeste E.; Hao, Li; Ramsay, James G.; Accardi, Carolyn R.; Cotsonis, George A.; Jones, Dean P.; Galloway, John R.; Ziegler, Thomas R.

    2011-01-01

    Background Nosocomial infections are an important cause of morbidity and mortality in the surgical intensive care unit (SICU). Clinical benefits of glutamine-supplemented parenteral nutrition may occur in hospitalized surgical patients, but efficacy data in different surgical subgroups are lacking. The objective was to determine whether glutamine-supplemented parenteral nutrition differentially affects nosocomial infection rates in selected subgroups of SICU patients. Methods This was a double-blind, randomized, controlled study of alanyl-glutamine dipeptide-supplemented parenteral nutrition in SICU patients requiring parenteral nutrition and SICU care after surgery for pancreatic necrosis, cardiac, vascular, or colonic surgery. Subjects (n = 59) received isocaloric/isonitrogenous parenteral nutrition, providing 1.5 g/kg/d standard glutamine-free amino acids (STD-PN) or 1.0 g/kg/d standard amino acids + 0.5 g/kg/d glutamine dipeptide (GLN-PN). Enteral feedings were advanced as tolerated. Nosocomial infections were determined until hospital discharge. Results Baseline clinical/metabolic data were similar between groups. Plasma glutamine concentrations were low in all groups and were increased by GLN-PN. GLN-PN did not alter infection rates after pancreatic necrosis surgery (17 STD-PN and 15 GLN-PN patients). In nonpancreatic surgery patients (12 STD-PN and 15 GLN-PN), GLN-PN was associated with significantly decreased total nosocomial infections (STD-PN 36 vs GLN-PN 13, P < .030), bloodstream infections (7 vs 0, P < .01), pneumonias (16 vs 6, P < .05), and infections attributed to Staphylococcus aureus (P < .01), fungi, and enteric Gram-negative bacteria (each P < .05). Conclusions Glutamine dipeptide-supplemented parenteral nutrition did not alter infection rates following pancreatic necrosis surgery but significantly decreased infections in SICU patients after cardiac, vascular, and colonic surgery. PMID:18596310

  15. Effect of acute nitrogen dioxide exposure on the composition of fatty acid associated with phospholipids in alveolar lavage

    SciTech Connect

    Kobayashi, T.; Noguchi, T.; Kikuno, M.; Kubota, K.

    1984-01-01

    In vivo exposure of rats to 10 ppm nitrogen dioxide (NO/sub 2/) for 12 h caused changes in fatty acids composition of alveolar lavage phospholipids. Among the fatty acid species, the relative ratio of palmitic acid, myristic acid and palmitoleic acid increased significantly. While the relative ratio of stearic acid, oleic acid, linoleic acid and arachidonic acid decreased significantly. Both the increase in the incorporation of palmitic acid in phosphatidylcholine which would be released into the alveoli and the increase in the release of phosphatidylcholine into the alveoli may account for the changes in the fatty acid composition of the present findings.

  16. Amino acid nitrogen isotopic composition patterns in lacustrine sedimenting matter

    NASA Astrophysics Data System (ADS)

    Carstens, Dörte; Lehmann, Moritz F.; Hofstetter, Thomas B.; Schubert, Carsten J.

    2013-11-01

    Amino acids (AAs) comprise a large fraction of organic nitrogen (N) in plankton and sedimenting matter. Aquatic studies of organic N compounds in general and of AAs in particular, mostly concentrate on marine environments. In order to study the cycling and fate of organic N and AAs in lakes, we measured the N isotopic composition (?15N) of bulk organic matter (OM) and of single hydrolysable AAs in sediment trap and sediment samples from two Swiss lakes with contrasting trophic state: Lake Brienz, an oligotrophic lake with an oxic water column, and Lake Zug a eutrophic, meromictic lake. We also measured the N isotopic composition of water column nitrate, the likely inorganic N source during biosynthesis in both lakes. The ?15N-AA patterns found for the sediment trap material were consistent with published ?15N-AA data for marine plankton. The AA composition and primary ?15N-AA signatures are preserved until burial in the sediments. During early sedimentary diagenesis, the ?15N values of single AAs appear to increase, exceeding those of the bulk OM. This increase in ?15N-AA is paralleled by a decreased contribution of AAs to the total OM pool with progressed degradation, suggesting preferential AA degradation associated with a significant N isotope fractionation. Indicators for trophic level based on ?15N-AAs were determined, for the first time in lacustrine systems. In our samples, the trophic AAs were generally enriched in 15N compared to source AAs and higher trophic ?15N-AA values in Lake Zug were consistent with a higher trophic level of the bulk biomass compared to Lake Brienz. Especially the difference between average trophic ?15N-AAs and average source ?15N-AAs was sensitive to the trophic states of the two lakes. A proxy for total heterotrophic AA re-synthesis (?V), which is strongly associated with heterotrophic microbial reworking of the OM, was calculated based on ?15N values of trophic AAs. Higher ?V in Lake Brienz indicate enhanced heterotrophic bacterial reworking of AAs under oligotrophic conditions. Despite changes in the ?15N-AA values within the sediments, the proxies based on these values were consistent over the studied sediment profile, indicating the preservation of trophic signatures; therefore, our results underscore that ?15N-AA analysis of sedimentary records represents a promising tool to assess trophic levels and bacterial re-synthesis in lakes.

  17. Gender Differences in Rat Erythrocyte and Brain Docosahexaenoic Acid Composition: Role of Ovarian Hormones and Dietary Omega-3 Fatty Acid Composition

    PubMed Central

    McNamara, Robert K.; Able, Jessica; Jandacek, Ronald; Rider, Therese; Tso, Patrick

    2009-01-01

    The two-fold higher prevalence rate of major depression in females may involve vulnerability to omega-3 fatty acid deficiency secondary to a dysregulation in ovarian hormones. However, the role of ovarian hormones in the regulation of brain omega-3 fatty acid composition has not been directly evaluated. Here we determined erythrocyte and regional brain docosahexaenoic acid (DHA, 22:6n-3) composition in intact male and female rats, and in chronically ovariectomized (OVX) rats with or without cyclic estradiol treatment (2 ?g/4 d). All groups were maintained on diets with or without the DHA precursor alpha-linolenic acid (ALA, 18:3n-3). We report that both male (?21%) and OVX (?19%) rats on ALA+ diet exhibited significantly lower erythrocyte DHA composition relative to female controls. Females on ALA+ diet exhibited lower DHA composition in the prefrontal cortex (PFC) relative males (?5%). OVX rats on ALA+ diet exhibited significantly lower DHA composition in the hippocampus (?6%), but not in the PFC, hypothalamus, or midbrain. Lower erythrocyte and hippocampus DHA composition in OVX rats was not prevented by estrogen replacement. All groups maintained on ALA? diet exhibited significantly lower erythrocyte and regional brain DHA composition relative to groups on ALA+ diet, and these reductions were greater in males but not in OVX rats. These preclinical data corroborate clinical evidence for gender differences in peripheral DHA composition (female>male), demonstrate gender differences in PFC DHA composition (male>female), and support a link between ovarian hormones and erythrocyte and region-specific brain DHA composition. PMID:19046819

  18. Original article Fatty acid composition of abdominal adipose tissue

    E-print Network

    Paris-Sud XI, Université de

    ). The palmitic and oleic acid proportions were comparable in the AAT of chickens fed with the different diets. The proportion of linoleic acid, obtained exclusively by the di- ets, was significantly higher in the chickens acids (UFA) similar to olive oil [14]). The major fatty acids (FA) in acorns are oleic (66.8%), palmitic

  19. Intramolecular condensation reactions in protonated dipeptides: carbon monoxide, water, and ammonia losses in competition.

    PubMed

    Pingitore, Francesco; Polce, Michael J; Wang, Ping; Wesdemiotis, Chrys; Paizs, Béla

    2004-07-01

    The elimination of carbon monoxide and water from a series of protonated dipeptides, [XxxYyy + H](+), is investigated by tandem mass spectrometry experiments and density functional theory. The combined results show that CO loss occurs on the a(1)-y(1) pathway, which begins by rearrangement of the added proton to the amide N-atom and creates the proton-bound dimer of an amino acid (Yyy) and an imine (that from Xxx residue). The loss of H(2)O is initiated from a tautomer in which the added proton has migrated to the hydroxyl group of the C-terminus, thereby promoting the formation of an ion with protonated oxazolone structure (a nominal b(2) ion). The highest yields of [XxxYyy + H - CO](+) and [XxxYyy + H - H(2)O](+) are observed at threshold energies. As the internal energy of the protonated dipeptides increases, these primary products are depleted by consecutive dissociations yielding mostly backbone fragments. Specifically, [XxxYyy + H - CO](+) decomposes to y(1) (protonated Yyy) and a(1) (immonium ion of Xxx residue), while [XxxYyy + H - H(2)O](+) produces a(2) and the immonium ions of residues Xxx (a(1)) and Yyy ("internal" immonium ion). Water loss takes place more efficiently when the more basic residue is at the C-terminal position. Increasing the basicity of the N-terminal residue enhances the extent of CO versus H(2)O loss and introduces the competitive elimination of NH(3). The dissociations leading to eliminations of small neutrals (CO, H(2)O, etc.) generally proceed over transition states that lie higher in energy than the corresponding dissociation products. The excess energy is disposed of either in translational or rovibrational modes of the products, depending on the stability of the incipient noncovalent assemblies emerging during the cleavage of the small neutrals. PMID:15234362

  20. Lipid composition of a newly isolated polyunsaturated fatty acid-producing fungus, Achlya sp. ma-2801

    Microsoft Academic Search

    Tsunehiro Aki; Yukimasa Matsumoto; Tsutomu Morinaga; Seiji Kawamoto; Seiko Shigeta; Kazuhisa Ono; Osamu Suzuki

    1998-01-01

    A polyunsaturated fatty acid-producing fungus, Achlya sp. ma-2801, was newly isolated from fresh-water samples obtained in Hiroshima Prefecture, Japan and was investigated with respect to its intracellular lipids and fatty acid composition under various cultural conditions. The eicosapentaenoic acid (EPA) and arachidonic acid (AA) contents reached 32.5 and 61.7 mg\\/g-dry cell weight, respectively, when grown in a medium consisting of

  1. Chromatographie analysis of seed oils. Fatty acid composition of castor oil

    Microsoft Academic Search

    R. G. Binder; T. H. Applewhite; G. O. Kohler; L. A. Goldblatt

    1962-01-01

    The fatty acid composition of a number of domestic and foreign castor oils was determined by consecutive column and gas-liquid\\u000a Chromatographic analysis. After saponification of the oils and removal of the unsaponifiables, the nonhydroxy, monohydroxy,\\u000a and dihydroxy acids were fractionated by partition chromatography on silicic acid. The amount of acid in each fraction was\\u000a determined by titration or weighing. Gravimetric

  2. Long-Chain Polyunsaturated Fatty Acid Composition of Breast Milk in Pre-Eclamptic Mothers

    Microsoft Academic Search

    Kamini D. Dangat; Savita S. Mehendale; Hemlata R. Yadav; Anitha S. Kilari; Asmita V. Kulkarni; Vaishali S. Taralekar; Sadhana R. Joshi

    2010-01-01

    Background: Maternal fatty acid nutrition during pregnancy and lactation determines the transfer of long-chain polyunsaturated fatty acids via the placenta and through human milk. Neural maturation of breast-fed infants is known to be linked to breast-milk long-chain polyunsaturated fatty acid concentrations. In spite of this, the fatty acid composition of breast milk in pre-eclamptic mothers is poorly understood. Objectives: To

  3. Preparation, morphology and properties of acid and amine modified multiwalled carbon nanotube\\/polyimide composite

    Microsoft Academic Search

    Siu-Ming Yuen; Chen-Chi M. Ma; Yao-Yu Lin; Hsu-Chiang Kuan

    2007-01-01

    The precursor of polyimide, polyamic acid, was prepared by reacting 4,4?-oxydianiline (ODA) with 3,3?,4,4?-benzophenone tetracarboxylic dianhydride (BTDA). Unmodified, acid-modified and amine-modified multiwall carbon nanotubes (MWCNT) were separately added to the polyamic acid and heated to 300°C to produce polyimide\\/carbon nanotube composite. Scanning electron microscopic (SEM) and transmission electron microscopic (TEM) microphotographs reveal that acid-modified MWCNT and amine-modified MWCNT were dispersed

  4. Observation of Single-File Diffusion in Dipeptide Nanotubes by Xenon-129 High Field NMR Diffusometry

    E-print Network

    Weston, Ken

    Observation of Single-File Diffusion in Dipeptide Nanotubes by Xenon-129 High Field NMR evidence for molecular single file diffusion of xenon gas confined inside model nanotube systems, i.e. L of xenon measured by Xe-129 PFG NMR in dipeptide nanotubes at 298 K. The experimental data in the figure

  5. Morphological Versatility in the Self-Assembly of Val-Ala and Ala-Val Dipeptides.

    PubMed

    Erdogan, Hakan; Babur, Esra; Yilmaz, Mehmet; Candas, Elif; Gordesel, Merve; Dede, Yavuz; Oren, Ersin Emre; Demirel, Gokcen Birlik; Ozturk, Mustafa Kemal; Yavuz, Mustafa Selman; Demirel, Gokhan

    2015-07-01

    Since the discovery of dipeptide self-assembly, diphenylalanine (Phe-Phe)-based dipeptides have been widely investigated in a variety of fields. Although various supramolecular Phe-Phe-based structures including tubes, vesicles, fibrils, sheets, necklaces, flakes, ribbons, and wires have been demonstrated by manipulating the external physical or chemical conditions applied, studies of the morphological diversity of dipeptides other than Phe-Phe are still required to understand both how these small molecules respond to external conditions such as the type of solvent and how the peptide sequence affects self-assembly and the corresponding molecular structures. In this work, we investigated the self-assembly of valine-alanine (Val-Ala) and alanine-valine (Ala-Val) dipeptides by varying the solvent medium. It was observed that Val-Ala dipeptide molecules may generate unique self-assembly-based morphologies in response to the solvent medium used. Interestingly, when Ala-Val dipeptides were utilized as a peptide source instead of Val-Ala, we observed distinct differences in the final dipeptide structures. We believe that such manipulation may not only provide us with a better understanding of the fundamentals of the dipeptide self-assembly process but also may enable us to generate novel peptide-based materials for various applications. PMID:26086903

  6. Controllable self-assembled laminated nanoribbons from dipeptide-amphiphile bearing azobenzene moiety

    E-print Network

    Huang, Jianbin

    Controllable self-assembled laminated nanoribbons from dipeptide-amphiphile bearing azobenzene nanostructures and biomaterials. In this paper, a dipeptide- amphiphile incorporated with an azobenzene moiety, Stupp has reported pH-induced self-assembly of a peptide-amphiphile to make nanostructured fibrous

  7. Growth temperature affects accumulation of exogenous fatty acids and fatty acid composition in Schizosaccharomyces pombe

    Microsoft Academic Search

    Virginia M. McDonough; Therese M. Roth

    2004-01-01

    The incorporation of exogenously supplied fatty acids, palmitic acid, palmitoleic acid, oleic acid and linoleic acid, was examined in the yeast Schizosaccharomyces pombe at two growth temperatures, 20 °C and 30 °C. Fatty acids supplied to S. pombe in the growth medium were found to be preferentially incorporated into the cells, becoming a dominant species. The relative increase in exogenous

  8. Predicting membrane protein types by fusing composite protein sequence features into pseudo amino acid composition.

    PubMed

    Hayat, Maqsood; Khan, Asifullah

    2011-02-21

    Membrane proteins are vital type of proteins that serve as channels, receptors, and energy transducers in a cell. Prediction of membrane protein types is an important research area in bioinformatics. Knowledge of membrane protein types provides some valuable information for predicting novel example of the membrane protein types. However, classification of membrane protein types can be both time consuming and susceptible to errors due to the inherent similarity of membrane protein types. In this paper, neural networks based membrane protein type prediction system is proposed. Composite protein sequence representation (CPSR) is used to extract the features of a protein sequence, which includes seven feature sets; amino acid composition, sequence length, 2 gram exchange group frequency, hydrophobic group, electronic group, sum of hydrophobicity, and R-group. Principal component analysis is then employed to reduce the dimensionality of the feature vector. The probabilistic neural network (PNN), generalized regression neural network, and support vector machine (SVM) are used as classifiers. A high success rate of 86.01% is obtained using SVM for the jackknife test. In case of independent dataset test, PNN yields the highest accuracy of 95.73%. These classifiers exhibit improved performance using other performance measures such as sensitivity, specificity, Mathew's correlation coefficient, and F-measure. The experimental results show that the prediction performance of the proposed scheme for classifying membrane protein types is the best reported, so far. This performance improvement may largely be credited to the learning capabilities of neural networks and the composite feature extraction strategy, which exploits seven different properties of protein sequences. The proposed Mem-Predictor can be accessed at http://111.68.99.218/Mem-Predictor. PMID:21110985

  9. Impact of dietary fatty acids on muscle composition, liver lipids, milt composition and sperm performance in European eel.

    PubMed

    Butts, Ian Anthony Ernest; Baeza, Rosa; Støttrup, Josianne Gatt; Krüger-Johnsen, Maria; Jacobsen, Charlotte; Pérez, Luz; Asturiano, Juan F; Tomkiewicz, Jonna

    2015-05-01

    In order for European eel aquaculture to be sustainable, the life cycle should be completed in captivity. Development of broodstock diets may improve the species' reproductive success in captivity, through the production of high-quality gametes. Here, our aim was to evaluate the influence of dietary regime on muscle composition, and liver lipids prior to induced maturation, and the resulting sperm composition and performance. To accomplish this fish were reared on three "enhanced" diets and one commercial diet, each with different levels of fatty acids, arachidonic acid (ARA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA). Neutral lipids from the muscle and liver incorporated the majority of the fatty acid profile, while phospholipids incorporated only certain fatty acids. Diet had an effect on the majority of sperm fatty acids, on the total volume of extractable milt, and on the percentage of motile sperm. Here, our results suggest that the total volume of extractable milt is a DHA-dependent process, as we found the diets with the highest DHA levels induced the most milt while the diet with the lowest DHA level induced the least amount of milt. The diet with the highest level of ARA induced medium milt volumes but had the highest sperm motility. EPA also seems important for sperm quality parameters since diets with higher EPA percentages had a higher volume of milt and higher sperm motility. In conclusion, dietary fatty acids had an influence on fatty acids in the tissues of male eel and this impacted sperm performance. PMID:25638567

  10. Purification and characterization of a novel imidazole dipeptide synthase from the muscle of the Japanese eel Anguilla japonica.

    PubMed

    Tsubone, Shiori; Yoshikawa, Naoko; Okada, Shigeru; Abe, Hiroki

    2007-04-01

    We have purified a novel enzyme from eel white muscle which catalyzes the syntheses of imidazole dipeptides, such as carnosine (beta-alanyl-L-histidine), anserine (beta-alanyl-pi-methyl-L-histidine), and balenine (ophidine; beta-alanyl-tau-methyl-L-histidine), directly from their precursors. The enzyme was purified 1130-fold from eel muscle by a series of column chromatographies. Although eel muscle contains a large amount of carnosine and only trace amounts of anserine and balenine, the anserine synthesizing activity was by far the highest. From gel permeation chromatography, the molecular mass of the enzyme was calculated to be 275kDa. SDS-PAGE of the purified enzyme represented a band around 43kDa, suggesting that the native enzyme is a hexamer or heptamer. The optimal pH and temperature were around 9.5 and 60 degrees C, respectively. K(m) values for beta-alanine and pi-methyl-L-histidine were 44 and 89mM, respectively. The enzyme was greatly activated by Zn(2+) and inhibited by EDTA. The N-terminal amino acid sequence of 25 residues of the purified enzyme showed 52% amino acid identity to 38-62 residues of zebrafish haptoglobin precursor. The purified enzyme also exhibited hydrolytic activity against these imidazole dipeptides. PMID:17261377

  11. Report-The fatty acid composition and physicochemical properties of the underutilised Cassia abbreviata seed oil.

    PubMed

    Dangarembizi, Rachael; Chivandi, Eliton; Dawood, Sumaya; Erlwanger, Kennedy Honey; Gundidza, Mazuru; Magwa, Michael Libala; Muredzi, Perkins; Samie, Amidou

    2015-05-01

    The fatty acid composition of the underutilised Cassia abbreviata seed oil was determined using gas chromatographic methods. C. abbreviata seeds yielded 9.53% of yellowish-green oil consisting mainly of oleic acid (37.8%), palmitic acid (26.5%), linoleic acid (26.7%), stearic acid (4.1%) and elaidic acid (2.1%). The oil was solid at room temperature, had a saponification value of 376.16 mg KOH/g and an iodine value of 26.48 g I2/100g oil. The fatty acid composition and saponification value of the C. abbreviata seed oil suggest that it may find application in both cosmetic and pharmaceutical natural product formulations. PMID:26004707

  12. Brain and liver fatty acid composition changes upon consumption of Lactobacillus rhamnosus LA68.

    PubMed

    Ivanovic, Nevena; Minic, Rajna; Djuricic, Ivana; Dimitrijevic, Ljiljana; Sobajic, Sladjana; Zivkovic, Irena; Djordjevic, Brizita

    2015-02-01

    Recent reports suggest that the metabolic activity of the enteric microbiota may influence the fatty acid composition of the host tissue. There are many studies dealing with the influence of lactobacilli on various pathological conditions, and some of the effects are strain-specific. This study was designed to test the effects of a particular Lactobacillus strain, Lactobacillus rhamnosus LA68 on fatty acid composition of the liver and the brain of C57BL/6 mice in the absence of an underlying pathological condition. Female mice were supplemented with live L. rhamnosus LA68 bacteria for the duration of 1 month. Serum biochemistry was analyzed and liver and brain fatty acid composition was assessed by gas-liquid chromatography. Significant changes in liver and brain fatty acid composition were detected. In the liver tissue we detected an increase in palmitoleic acid (p?=?0.038), while in the brain compartment we found an increase in palmitic (p?=?0.042), stearic (p?=?0.017), arachidonic acid (p?=?0.009) and docosahexaenoic acid (p?=?0.004) for control versus experimental group. These results show discrete changes caused by LA68 strain consumption. Even short duration of administration of LA68 influences the fatty acid composition of the host which adds to the existing knowledge about Lactobacillus host interaction, and adds to the growing knowledge of metabolic intervention possibilities. PMID:25431181

  13. Modifications prcoces de la composition en acides gras des cardiolipides

    E-print Network

    Paris-Sud XI, Université de

    to reach a level analogous to that of control rats. The diminution of linoleic acid in CL was brought about of palmitic acid in CL and in PLm during the first 3 days. In CL, this effect was reversed less than 2 days direction to that of palmitic acid in PLm. Introduction. Chez les animaux, les cardiolipides (CL), ou

  14. Growth temperature affects accumulation of exogenous fatty acids and fatty acid composition in Schizosaccharomyces pombe

    Microsoft Academic Search

    Virginia M. McDonough; Therese M. Roth

    2004-01-01

    The incorporation of exogenously supplied fatty acids, palmitic acid, palmitoleic acid, oleic acid and linoleic acid, was\\u000a examined in the yeast Schizosaccharomyces pombe at two growth temperatures, 20?C and 30?C. Fatty acids supplied to S. pombe in the growth medium were found to be preferentially incorporated into the cells, becoming a dominant species. The relative\\u000a increase in exogenous fatty acids

  15. Regional differences in fatty acid composition in common minke whales (Balaenoptera acutorostrata) from the North Atlantic

    E-print Network

    Ruzzante, Daniel E.

    Regional differences in fatty acid composition in common minke whales (Balaenoptera acutorostrata from 170 common minke whales (Balaenoptera acutorostrata) was used to study population structure can be used for studying population structure in minke whales. Potential variation in FA signatures

  16. Fatty acid composition as a tool for screening alternative feedstocks for production of biodiesel

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fatty acid (FA) composition was used as a screening tool for the selection of feedstocks high in monounsaturated content for evaluation as biodiesel. The feedstocks were ailanthus (Ailanthus altissima), anise (Pimpinella anisum), arugula (Eruca vesicaria), camelina (Camelina sativa), coriander (Cori...

  17. Changes in fatty acid and hydrocarbon composition of zooplankton assemblages related to environmental conditions

    SciTech Connect

    Lambert, R.M.

    1989-01-01

    Changes in zooplankton fatty acid and hydrocarbon patterns are described in relation to changes in environmental conditions and species composition. The regulation of zooplankton abundance by sea nettle-ctenophore interaction was examined in a small Rhode Island coastal pond. Sea nettles were nettles were able to eliminate ctenophores from the pond and subsequently zooplankton abundance increased. During one increase in zooplankton abundance, it was found that polyunsaturated fatty acids decreased while monounsaturated fatty acids increased. It was concluded that this shift in biochemical pattern was due to food limitation. In addition, zooplankton fatty acids were used in multivariate discriminant analysis to classify whether zooplankton were from coastal or estuarine environments. Zooplankton from coastal environments were characterized by higher monounsaturate fatty acids. Zooplankton hydrocarbon composition was affected by species composition and by pollution inputs. The presence of Calanus finmarchicus was detected by increased levels of pristane.

  18. Simultaneous determination of ascorbic acid and dopamine at a sol–gel composite electrode

    Microsoft Academic Search

    D. Ravi Shankaran; K. Iimura; T. Kato

    2003-01-01

    A new sol–gel composite electrode containing dispersed copper was fabricated using (3-mercaptopropyl)trimethoxysilane (MPS) and copper nitrate. The sensor exhibited excellent characteristics for simultaneous determination of ascorbic acid and dopamine owing to its combined features of sol–gel composite and copper catalysis. The peaks for the oxidation of ascorbic acid and dopamine were well resolved at the reduced potentials with good sensitivity.

  19. Boron-free fibers for prevention of acid induced brittle fracture of composite insulator GRP rods

    Microsoft Academic Search

    Daniel L. Armentrout; Maciej Kumosa; Terry S. McQuarrie

    2003-01-01

    An investigation was performed to determine whether corrosion resistant boron-free E-glass fibers could adequately prevent acid induced brittle fracture failures of high voltage composite insulator rods. Nine different rod compositions were tested at 45% of mechanical failure load in contact with 1 N nitric acid. Rods made out of commonly used E-glass fibers failed mechanically in less than 2 h

  20. Some applications of deoxyribonucleic acid base composition in bacterial taxonomy

    Microsoft Academic Search

    J. De Ley; J. Van Muylem

    1963-01-01

    The “melting point”Tm, the mean molar (guanine+cytosine) composition and the compositional distribution of purified DNA from several strains ofXanthomonas, Chromobacterium and yellow-pigmented marine bacteria have been determined. These groups were selected because they had been analyzed adansonially. Ten strains ofXanthomonas had an average molar (guanine+cytosine) composition within the range 66.0–68.2%, which was very close to that ofPseudomonas (60–68%), as expected.

  1. Cluster analysis identifies aminoacid compositional features that indicate Toxoplasma gondii adhesin proteins

    PubMed Central

    Arenas, Ailan F; Salcedo, Gladys E; Moncada, Diego M; Erazo, Diego A; Osorio, Juan F; Gomez-Marin, Jorge E

    2012-01-01

    Toxoplasma gondii invade host cells using a multi-step process that depends on the regulated secretion of adhesions. To identify key primary sequence features of adhesins in this parasite, we analyze the relative frequency of individual amino acids, their dipeptide frequencies, and the polarity, polarizability and Van der Waals volume of the individual amino acids by using cluster analysis. This method identified cysteine as a key amino acid in the Toxoplasma adhesin group. The best vector algorithm of non-concatenated features was for 2 attributes: the single amino acid relative frequency and the dipeptide frequency. Polarity, polarizability and Van der Waals volume were not good classificatory attributes. Single amino acid attributes clustered unambiguously 67 apicomplexan hypothetical adhesins. This algorithm was also useful for clustering hypothetical Toxoplasma target host receptors. All of the cluster performances had over 70% sensitivity and 80% specificity. Compositional aminoacid data can be useful for improving machine learning-based prediction software when homology and structural data are not sufficient. PMID:23144551

  2. Cluster analysis identifies aminoacid compositional features that indicate Toxoplasma gondii adhesin proteins.

    PubMed

    Arenas, Ailan F; Salcedo, Gladys E; Moncada, Diego M; Erazo, Diego A; Osorio, Juan F; Gomez-Marin, Jorge E

    2012-01-01

    Toxoplasma gondii invade host cells using a multi-step process that depends on the regulated secretion of adhesions. To identify key primary sequence features of adhesins in this parasite, we analyze the relative frequency of individual amino acids, their dipeptide frequencies, and the polarity, polarizability and Van der Waals volume of the individual amino acids by using cluster analysis. This method identified cysteine as a key amino acid in the Toxoplasma adhesin group. The best vector algorithm of non-concatenated features was for 2 attributes: the single amino acid relative frequency and the dipeptide frequency. Polarity, polarizability and Van der Waals volume were not good classificatory attributes. Single amino acid attributes clustered unambiguously 67 apicomplexan hypothetical adhesins. This algorithm was also useful for clustering hypothetical Toxoplasma target host receptors. All of the cluster performances had over 70% sensitivity and 80% specificity. Compositional aminoacid data can be useful for improving machine learning-based prediction software when homology and structural data are not sufficient. PMID:23144551

  3. The preferred conformation of dipeptides in the context of biosynthesis

    NASA Astrophysics Data System (ADS)

    Bywater, Robert P.; Veryazov, Valera

    2013-09-01

    Globular proteins are folded polypeptide structures comprising stretches of secondary structures (helical (?- or 310 helix type), polyproline helix or ?-strands) interspersed by regions of less well-ordered structure ("random coil"). Protein fold prediction is a very active field impacting inte alia on protein engineering and misfolding studies. Apart from the many studies of protein refolding from the denatured state, there has been considerable interest in studying the initial formation of peptides during biosynthesis, when there are at the outset only a few residues in the emerging polypeptide. Although there have been many studies employing quantum chemical methods of the conformation of dipeptides, these have mostly been carried out in the gas phase or simulated water. None of these conditions really apply in the interior confines of the ribosome. In the present work, we are concerned with the conformation of dipeptides in this low dielectric environment. Furthermore, only the residue types glycine and alanine have been studied by previous authors, but we extend this repertoire to include leucine and isoleucine, position isomers which have very different structural propensities.

  4. Contribution of Diet and Genes to Polyunsaturated Fatty Acid Composition

    Microsoft Academic Search

    Toshiko Tanaka

    2011-01-01

    Dietary recommendations for polyunsaturated fatty acids (PUFA) are based in part on results from epidemiologic studies to\\u000a determine the level of dietary PUFA required to maintain optimal health. There are many challenges to estimating consumption\\u000a of fatty acids through dietary surveys. PUFA measured in different biological samples have been used as biomarkers of fatty\\u000a acid consumption. In addition to diet,

  5. Sensitive Amino Acid Composition and Chirality Analysis with the Mars Organic Analyzer (MOA)

    NASA Technical Reports Server (NTRS)

    Skelley, Alison M.; Scherer, James R.; Aubrey, Andrew D.; Grover, William H.; Ivester, Robin H. C.; Ehrenfreund, Pascale; Grunthaner, Frank J.; Bada, Jeffrey L.; Mathies, Richard A.

    2005-01-01

    Detection of life on Mars requires definition of a suitable biomarker and development of sensitive yet compact instrumentation capable of performing in situ analyses. Our studies are focused on amino acid analysis because amino acids are more resistant to decomposition than other biomolecules, and because amino acid chirality is a well-defined biomarker. Amino acid composition and chirality analysis has been previously demonstrated in the lab using microfabricated capillary electrophoresis (CE) chips. To analyze amino acids in the field, we have developed the Mars Organic Analyzer (MOA), a portable analysis system that consists of a compact instrument and a novel multi-layer CE microchip.

  6. Oilseed Lipid Supplements and Fatty Acid Composition of Cow Milk: A Meta-Analysis

    Microsoft Academic Search

    F. Glasser; A. Ferlay; Y. Chilliard

    2008-01-01

    Numerous experiments have studied the use of oilseed supplements in cow diets to alter milk fatty acid (FA) composition, but no quantitative synthesis of these studies is currently available. This article re- ports a meta-analysis of the response of cow milk FA composition to oilseed lipid supplements from linseed, rapeseed, soybeans, and sunflower seed. First, from a database of 145

  7. EFFECT OF DIETARY FISH OIL ON THE FATTY ACID COMPOSITION AND PALATABILITY OF PIG TISSUES'

    E-print Network

    EFFECT OF DIETARY FISH OIL ON THE FATTY ACID COMPOSITION AND PALATABILITY OF PIG TISSUES' ROBERT R, such as fish meal, above a certain concentration in the diet. In this study, pigs were fed diets containing of composition to the taste of the meat. The principal findings of the study were: (1) The amount of the fish oil

  8. Starch/fiber/poly(lactic acid) foam and compressed foam composites

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Composites of starch, fiber, and poly(lactic acid) (PLA) were made using a foam substrate formed by dehydrating starch or starch/fiber gels. PLA was infiltrated into the dry foam to provide better moisture resistance. Foam composites were compressed into plastics using force ranging from 4-76MPa. Te...

  9. Fatty acid composition of intramuscular fat from pastoral yak and Tibetan sheep

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fatty acid (FA) composition of intramuscular fat from mature male yak (n=6) and mature Tibetan sheep (n=6) grazed on the same pasture in the Qinghai-Tibetan Plateau was analyzed by gas chromatograph/mass spectrometer to characterize fat composition of these species and to evaluate possible differenc...

  10. Relation between Fatty Acid Composition and Clinical Status or Genotype in Cystic Fibrosis Patients

    Microsoft Academic Search

    Stephanie Van Biervliet; Griet Vanbillemont; Jean-Pierre Van Biervliet; Dimitri Declercq; Eddy Robberecht; Armand Christophe

    2007-01-01

    Objective: To evaluate the relation of clinical parameters and genotype with the serum phospholipid fatty acid (FA) composition in cystic fibrosis (CF) patients. Methods: A blood sample was taken from CF patients with stable pulmonary disease for the determination of phospholipid FA composition and vitamin E concentration who had been followed for at least 6 months at our Cystic Fibrosis

  11. Sugar beet pulp and poly(lactic acid) composites using methylene diphenyl diisocyanate as coupling agent

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Composites from sugar beet pulp (SBP) and poly(lactic acid) (PLA) were extruded in the presence of polymeric methylene diphenyl diisocyanate (pMDI). SBP particles were evenly distributed within the PLA matrix phase as revealed by confocal fluorescence microscopic analysis. The resultant composites w...

  12. Proximate, mineral and fatty acid composition of fast foods consumed in Bahrain

    Microsoft Academic Search

    Abdulrahman O. Musaiger; Jassim H. Al-Jedah; Reshma Dsouza

    2008-01-01

    Purpose – The purpose of this paper is to evaluate the commonly consumed fast foods in Bahrain with respect to proximate, mineral, sterol composition and their fatty acid profile. Design\\/methodology\\/approach – Foods were purchased from the most frequented fast food outlets in Manama city, the capital of Bahrain. Similar types of foods were pooled into one sample. Proximate composition was

  13. Poly(lactic acid) and Osage Orange Wood Fiber Composites for Agricultural Mulch Films

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Osage orange wood was combined with poly(lactic acid) to form a polymer composite intendedfor use as an agricultural mulch film. The mechanical properties were comparable to existing products and had the advantage of being completely biodegradable through a single growing season. PLA-OO composites...

  14. EVALUATION OF POLY(LACTIC ACID) AND SUGAR BEET PULP GREEN COMPOSITES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Poly(lactic acid) and sugar beet pulp were compounded by twin-screw extrusion and injection molded into composite forms. Specific mechanical energy decreased with the addition of SBP during processing. PLA-SBP composites retained more tensile strength than expected based on the Nicolais-Narkis mod...

  15. Method and compositions for reducing corrosion in the removal of acidic gases from gaseous mixtures

    Microsoft Academic Search

    M. S. DuPart; D. C. Cringle; B. D. Oakes

    1984-01-01

    A corrosion inhibited composition containing a gas conditioning solution such as an alkanol amine with water or with organic solvents and with small amounts of soluble thiocyanate compounds, soluble trivalent bismuth compounds with or without soluble divalent nickel or cobalt compounds. The compositions are useful to separate acid gases such as carbon dioxide from hydrocarbon feed streams in gas conditioning

  16. Fatty acids, protein contents and metal composition of some feed crops from Turkey

    Microsoft Academic Search

    Adil Bakoglu; Eyüp Bagci; Harun Ciftci

    In the course of investigations of new sources of higher plant lipids, fatty acid and metal compositions of some feed crops -Vicia ervilia (bitter veitch), Lotus corniculatus, Onobrychis fallax, Trifolium aureum (golden clover), Trifolium repens (white clover) (Fabaceae)- from Turkey were investigated by using GC and ICP-OES system. All the legume crops showed the same pattern of fatty acids. The

  17. Effects of Sucking Acidic Candy on Whole-Mouth Saliva Composition

    Microsoft Academic Search

    T. Jensdottir; B. Nauntofte; C. Buchwald; A. Bardow

    2005-01-01

    Limited information is available on the effects of sucking acidic candies on saliva composition and the protective role of saliva in this relation. Therefore the aim of this study was to determine salivary effects of sucking acidic candies in vivo in relation to individual variations in whole-saliva flow rate (WSFR) and buffer capacity (WS?). Ten healthy young males (24 ±

  18. Plasma and neutrophil fatty acid composition in advanced cancer patients and response to fish oil supplementation

    Microsoft Academic Search

    V C Pratt; S Watanabe; E Bruera; J Mackey; M T Clandinin; V E Baracos; C J Field

    2002-01-01

    Metabolic demand and altered supply of essential nutrients is poorly characterised in patients with advanced cancer. A possible imbalance or deficiency of essential fatty acids is suggested by reported beneficial effects of fish oil supplementation. To assess fatty acid status (composition of plasma and neutrophil phospholipids) in advanced cancer patients before and after 14 days of supplementation (12±1 g day?1)

  19. Fatty Acid Composition of Mitochondrial Membrane Lipids in Cultivated ( Zea mays ) and Wild ( Elymus sibiricus ) Grasses

    Microsoft Academic Search

    S. P. Makarenko; Y. M. Konstantinov; S. V. Khotimchenko; T. A. Konenkina; A. Sh. Arziev

    2003-01-01

    The fatty acid composition of mitochondrial membrane lipids from seedlings of two grass species differing in their chilling tolerance, elymus (Elymus sibiricus) and maize (Zea mays), was studied by gas-liquid chromatography. An increased chilling tolerance of elymus, a perennial wild species, seems to be caused by a high content of unsaturated fatty acid residues in the total membrane lipids; linoleic

  20. Genetic regulation of bovine milk fatty acid composition: Improving the healthfulness of milk through selection

    Microsoft Academic Search

    Rafael Nafikov

    2010-01-01

    The current study was designed to identity polymorphisms in the genes involved in milk lipid biosynthesis to provide animal breeders with tools that allow selection of animals producing milk with healthier fatty acid composition. High concentrations of saturated fatty acids (SFA) in human diets are known to increase plasma cholesterol concentrations and, as a result, increase the risk of developing

  1. Milk fatty acid composition of indigenous goat and ewe breeds from Sindh, Pakistan

    Microsoft Academic Search

    Farah N. Talpur; M. I. Bhanger; Nusrat N. Memon

    2009-01-01

    The present study was undertaken to evaluate the breed influence on milk fatty acid (FA) composition, particularly on the concentration of conjugated linoleic acid (CLA) from two different indigenous breeds of goats (Pateri and Kamori; n=30 for each breed) and ewes (Kachi and Kooka; n=25 for each) from Sindh, Pakistan. All animals were managed together and received the same diet.

  2. Impact of potato psyllid (Hemiptera: Triozide) feeding on free amino acid composition in potato

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Foliage feeding impacts of potato psyllid (Bactericera cockerelli) on the free amino acids (FAAs) composition in potato leaf and tuber were determined under the greenhouse conditions. The free amino acids in plant extracts were separated by HPLC, and in both leaf and tuber samples, at least, 17 FAAs...

  3. Characterization of enzymatic saccharification for acid-pretreated lignocellulosic materials with different lignin composition

    Microsoft Academic Search

    Gia-Luen Guo; Deng-Chieh Hsu; Wen-Hua Chen; Wei-Hsi Chen; Wen-Song Hwang

    2009-01-01

    The enzymatic saccharification of three different feedstocks, rice straw, bagasse and silvergrass, which had been pretreated with different dilute acid concentrations, was studied to verify how enzymatic saccharification was affected by the lignin composition of the raw materials. There was a quantitatively inverse correlation between lignin content and enzymatic digestibility after pretreatment with 1%, 2% and 4% sulfuric acid. The

  4. The plant geneticist’ contribution toward changing lipid and amino acid composition of safflower

    Microsoft Academic Search

    P. F. Knowles

    1972-01-01

    Current research on the fatty acid composition of the seed oil of safflower (Carthamus tinctorius L.) has shown the following: (1) there is a possibility that the oleic acid content can be increased above 80%, though probably\\u000a not above 85%, by use of modifying genes and the major geneol; (2) wild species do not look very promising as a source

  5. Polylactic acid–phosphate glass composite foams as scaffolds for bone tissue engineering

    Microsoft Academic Search

    G. Georgiou; L. Mathieu; D. P. Pioletti; P.-E. Bourban; J.-A. E. Månson; J. C. Knowles; S. N. Nazhat

    2007-01-01

    Phosphate glass (PG) of the composition 0.46(CaO)- 0.04(Na2O)- 0.5(P2O5) was used as filler in poly-L-lactic acid (PLA) foams developed as degradable scaffolds for bone tissue engineering. The effect of PG on PLA was assessed both in bulk and porous composite foams. Composites with various PG content (0, 5, 10, and 20 wt %) were melt-extruded, and either compression-molded or foamed

  6. Morphology and properties of hybrid composites based on polypropylene\\/polylactic acid blend and bamboo fiber

    Microsoft Academic Search

    Zhang Ying-Chen; Wu Hong-Yan; Qiu Yi-Ping

    2010-01-01

    The design of new composites based on a polypropylene (PP)\\/polylactic acid (PLA) matrix and filler bamboo fiber (BF) leads to changes in process ability, morphology, and rheological properties of the raw thermoplastic. We have designed more environmentally friendly composites blended with PLA, filled with bamboo fiber. To refine dispersion of PLA and improve composite toughness, MAH-g-PP was included in the

  7. A comparative study on the chemical composition of humic acids from forest soil, agricultural soil and lignite deposit

    Microsoft Academic Search

    Béatrice Allard

    2006-01-01

    Base- and acid-hydrolysable fractions of humic acids (HAs) isolated from a forest soil, an agricultural soil and a lignite deposit were analysed, and comparisons were made between the base hydrolysable lipid (bound lipid), carbohydrate and amino acid signatures of the different humic acids.Bound lipids differ depending on the humic acid origin. Their composition were rather similar for the two soil

  8. Amino Acid and Vitamin Composition of Raw and Cooked Horse Mackerel

    Microsoft Academic Search

    Nuray Erkan; Arif Selçuk; Özkan Özden

    2010-01-01

    Amino acid, vitamin (A, E, B1, B2, B3 and B6), and proximate composition were determined in raw and cooked horse mackerel. The changes in amino acid, vitamin, and proximate\\u000a content were found to be significant for all cooking methods (frying, grilling, and steaming). Cooking did in general significantly\\u000a increase the contents of essential, semi-essential, and other amino acids compared to

  9. Effects of zinc deficiency and castration on fatty acid composition and desaturation in rats

    Microsoft Academic Search

    Sanda Clejan; Mariano Castro-Magana; Platon J. Collipp; Ernesto Jonas; Vaddanahally T. Maddaiah

    1982-01-01

    The effects of zinc deficiency and testosterone on fatty acid composition of plasma lipids and microsomes of liver, intestine\\u000a and testes were studied. The activities of fatty acid desaturase (?6 and ?5) in rat liver and testes were also measured. A\\u000a significant decrease in the level of arachidonic acid was observed in plasma of normal rats fed the zinc-deficient diet.

  10. Use of gas liquid chromatography for monitoring the fatty acid composition of canadian rapeseed

    Microsoft Academic Search

    J. K. Daun; P. B. Mazur; C. J. Marek

    1983-01-01

    Since 1972, Canadian rapeseed has been changing from high erucic acid types to low erucic acid types. In 1970, the Canadian\\u000a Grain Commission instituted a program to monitor the fatty acid composition of rapeseed at the farm level, in railway carlot\\u000a shipments and in export cargo shipments. Initially, in order to process up to 20,000 samples per year, a combined

  11. Oil content and fatty acid composition of promising Indian Brassica campestris L. (Toria) genotypes.

    PubMed

    Ahuja, K L; Batta, S K; Raheja, R K; Labana, K S; Gupta, M L

    1989-06-01

    Seeds of sixty four genotypes of Brassica campestris L. (Toria) were analyzed for oil content and fatty acid composition. Oil content varied from 38.9% to 44.6%. Major fatty acids viz. oleic, linoleic, linolenic, eicosenoic and erucic acids exhibited ranges from 10.1% to 17.3%, 5.9% to 14.5%, 5.2% to 15.0%, 7.7% to 13.7% and 39.6% to 59.9%, respectively. Compared to the standard cultivar ITSA, four genotypes contained 5 to 8% lower content of erucic acid; and six genotypes contained significantly higher content of linoleic acid. Oil was positively correlated with erucic acid. The observed inverse relationship between linoleic and erucic acid contents might be utilized in breeding nutritionally better Toria cultivars with both high linoleic and low erucic acid contents. PMID:2762244

  12. Fatty acid composition of larvae of the sand dollar Dendraster excentricus (Echinodermata) might reflect FA composition of the diets

    Microsoft Academic Search

    Sophie B. George; Colleen Fox; Stuart Wakeham

    2008-01-01

    Fatty acid (FA) requirements of echinoderm larvae were examined by a study of the FA composition, growth, and development of Dendraster excentricus larvae fed a microencapsulated diet, and two algal diets. Larvae were assigned to three treatments with three replicates per treatment, a microencapsulated diet, a single algal diet of Dunaliella tertiolecta and a mixed algal diet of Isochrysis galbana

  13. Composition and properties of acid tar and asphalt produced from acid tar

    Microsoft Academic Search

    A. F. Frolov; A. N. Aminov; S. D. Timrot

    1981-01-01

    Acid tar is a waste material that is produced in large volumes in treating petroleum oils with concentrated sulfuric acid. The acid tar contains up to 80% petroleum oils and tars and resins. In current practice, the acid tar Ss dumped into holding ponds that take up large areas of land; this practice leads to pollution of the ground, water,

  14. Group composition of carboxylic acids from West Siberian crude oils

    Microsoft Academic Search

    N. I. Zhil'tsov; V. A. Ershov; G. I. Samokhvalova

    1982-01-01

    with alkali [i]~ The physical and chemical properties of the crude oils from which the petroleum acids were obtained are listed in Table i, along with the results from chromatographic separation of the extracts into fractions of neutral substances, phenol, and carboxyiic acids. The deviation between results of parallel analyses was no greater than 15% (relative), and the losses in

  15. Natural fibres as reinforcement in polylactic acid (PLA) composites

    Microsoft Academic Search

    K. Oksman; M. Skrifvars; J.-F. Selin

    2003-01-01

    The focus in this work has been to study if natural fibres can be used as reinforcement in polymers based on renewable raw materials. The materials have been flax fibres and polylactic acid (PLA). PLA is a thermoplastic polymer made from lactic acid and has mainly been used for biodegradable products, such as plastic bags and planting cups, but in

  16. Ni(II)-mediated self-assembly of artificial beta-dipeptides forming a macrocyclic tetranuclear complex with interior spaces for in-line molecular arrangement.

    PubMed

    Miyake, Ryosuke; Tashiro, Shohei; Shiro, Motoo; Tanaka, Kentaro; Shionoya, Mitsuhiko

    2008-04-30

    Metal-mediated self-assembly of bioinspired molecular building blocks shows promise as an excellent strategy to provide well-defined metal arrays and nanoscopic metallo-architectures in a programmable way. Herein, we report Ni(II)-mediated self-assembly of artificial beta-dipeptides (1) which were prepared from a newly designed beta-amino acid bearing a propanediamine ligand as the side chain. The beta-dipeptide (1) has thus two sets of ligands, that is, each building block serves as a tridentate ligand with a bidentate propanediamine unit and an amide carbonyl group. Both C- and N-terminal tridentate ligands in 1 bind to two Ni(II) ions independently, and consequently, four beta-dipeptides are circularly arranged in a head-to-tail fashion to form a macrocyclic tetranuclear Ni(II) complex, Ni414(ClO4)8(H2O)10. The cyclic structure was determined by X-ray analysis and ESI-TOF mass spectrometry. The resulting unique twisted-boat structure allows the formation of isolated spaces for in-line hydrogen-bonded arrangement of water and anion molecules within a hole and two grooves rich in hydrogen bonding groups. PMID:18396868

  17. The fatty acid composition of Octopus vulgaris paralarvae reared with live and inert food: deviation from their natural fatty acid profile

    Microsoft Academic Search

    Juan C Navarro; Roger Villanueva

    2003-01-01

    The fatty acids of the mature ovary, late eggs and wild juveniles of Octopus vulgaris were analysed to establish, in accordance with the published data on the fatty acid composition of hatchlings, a theoretical framework of the ideal fatty acid profile, i.e. the “natural” fatty acid profile, during the early life of the species. The time course variation of the

  18. Influence of eicosapentaenoic to docosahexaenoic acid ratio ( EPA DHA ) of dietary lipids on growth and fatty acid composition of gilthead seabream ( Sparus aurata) juveniles

    Microsoft Academic Search

    C. Ibeas; J. R. Cejas; R. Fores; P. Badía; T. Gómez; A. Lorenzo Hernández

    1997-01-01

    A feeding experiment was conducted to investigate the influence of eicosapentaenoic acid (20:5n ? 3; EPA) to docosahexaenoic acid (22:6n ? 3; DHA) ratio (EPADHA) of dietary lipids on growth and fatty acid composition of gilthead seabream juveniles. Fish were fed three diets containing the same amount of total n ? 3 highly unsaturated fatty acids (n ? 3 HUFA)

  19. Effect of [alpha ]-linolenic acid[ndash ]rich Camelina sativa oil on serum fatty acid composition and serum lipids in hypercholesterolemic subjects

    Microsoft Academic Search

    Henna M. Karvonen; Antti Aro; Niina S. Tapola; Irma Salminen; Matti I. J. Uusitupa; Essi S. Sarkkinen

    2002-01-01

    Camelina sativa[ndash ]derived oil (camelina oil) is a good source of [alpha ]-linolenic acid. The proportion of [alpha ]-linolenic acid in serum fatty acids is associated with the risk of cardiovascular diseases. We studied the effects of camelina oil on serum lipids and on the fatty acid composition of total lipids in comparison to rapeseed and olive oils in a

  20. Carbon composite micro- and nano-tubes-based electrodes for detection of nucleic acids

    PubMed Central

    2011-01-01

    The first aim of this study was to fabricate vertically aligned multiwalled carbon nanotubes (MWCNTs). MWCNTs were successfully prepared by using plasma enhanced chemical vapour deposition. Further, three carbon composite electrodes with different content of carbon particles with various shapes and sizes were prepared and tested on measuring of nucleic acids. The dependences of adenine peak height on the concentration of nucleic acid sample were measured. Carbon composite electrode prepared from a mixture of glassy and spherical carbon powder and MWCNTs had the highest sensitivity to nucleic acids. Other interesting result is the fact that we were able to distinguish signals for all bases using this electrode. PMID:21711910

  1. Carbon composite micro- and nano-tubes-based electrodes for detection of nucleic acids.

    PubMed

    Prasek, Jan; Huska, Dalibor; Jasek, Ondrej; Zajickova, Lenka; Trnkova, Libuse; Adam, Vojtech; Kizek, Rene; Hubalek, Jaromir

    2011-01-01

    The first aim of this study was to fabricate vertically aligned multiwalled carbon nanotubes (MWCNTs). MWCNTs were successfully prepared by using plasma enhanced chemical vapour deposition. Further, three carbon composite electrodes with different content of carbon particles with various shapes and sizes were prepared and tested on measuring of nucleic acids. The dependences of adenine peak height on the concentration of nucleic acid sample were measured. Carbon composite electrode prepared from a mixture of glassy and spherical carbon powder and MWCNTs had the highest sensitivity to nucleic acids. Other interesting result is the fact that we were able to distinguish signals for all bases using this electrode. PMID:21711910

  2. Two-step one-pot synthesis of dihydropyrazinones as Xaa-Ser dipeptide isosteres through morpholine acetal rearrangement.

    PubMed

    Lenci, Elena; Innocenti, Riccardo; Menchi, Gloria; Faggi, Cristina; Trabocchi, Andrea

    2015-07-01

    The synthesis of the uncommon dihydropyrazinone ring was accomplished by a two-step one pot process taking advantage of the ring rearrangement of N-acylated morpholine acetal derived from serine under acidic treatment in the presence of 2,6-lutidine. The mechanism involves an N-acyl iminium intermediate resulting from morpholine acetal ring opening, which occurs after a nucleophilic attack of the amino acid nitrogen atom to the acetal carbonyl atom. X-Ray diffraction analysis of the dihydropyrazinone, which may be exploited as a constrained Xaa-Ser dipeptide isostere, showed a planar assembly and the internal side-chain in axial orientation with respect to the cyclic molecular scaffold. PMID:26030011

  3. Short communication: within-day variation in fatty acid composition of milk from cows in an automatic milking system.

    PubMed

    Larsen, M K; Weisbjerg, M R; Kristensen, C B; Mortensen, G

    2012-10-01

    Milk fatty acid composition is influenced by a range of conditions such as breed, feeding, and stage of lactation. Knowledge of milk fatty acid composition of individual cows would make it possible to sort milk at farm level according to certain fatty acid specifications. In the present study, 225 milk samples were taken from 84 cows in a herd equipped with an automatic milking system. Milk fat content varied depending on yield and time since last milking, whereas the milk fatty acid composition did not vary significantly within cow. It was concluded that random milk samples may be used for analysis of fatty acid composition. PMID:22901471

  4. Self-organization of dipeptide-grafted polymeric nanoparticles film: A novel method for surface modification

    Microsoft Academic Search

    Jingtian Han; Patrick Silcock; A. James McQuillan; Phil Bremer

    2010-01-01

    Novel dipeptide-grafted polymeric nanoparticles were prepared by grafting the dipeptide (Gly-Gly) to a block copolymer backbone, comprised of styrene-alt-(maleic anhydride) and styrene. In aqueous solution PSt130-b-P(St-alt-MAn)58-g-GlyGly26 formed stable dispersed spherical aggregates of ca. 75nm. The critical micelle concentration for the dipeptide-grafted block copolymer self-aggregates was 6.3×10?3mgmL?1. The zeta-potential of the aggregates was estimated experimentally. The dispersed polymer nanoparticles effectively self-organized

  5. Amino acid composition of cadmium-binding protein induced in a marine diatom

    SciTech Connect

    Maita, Y.; Kawaguchi, S. (Hokkaido Univ. (Japan))

    1989-09-01

    Organisms living in environments polluted with heavy metals develop tolerance against these contaminants. The tolerance has been attributed to the ability to synthesize metal binding substances. These recent findings imply metal binding complexes from animals and plants, although having very similar functional properties, may have entirely different amino acid compositions. Researchers reported that cadystin from fission yeast, Schizosaccharomyces pombe was composed of only glutamic acid, cysteine, and glycine. A year later, a heavy metal binding substance was isolated from Rauwolfia serpetina which contains only Glu, Cys, and Gly. Heavy metal binding complexes isolated from the water hyacinth and morning glory Datura innoxia also showed an amino acid composition similar to cadystin or phytochelatin. In this study, the cadmium binding protein induced in the marine diatom, Phaeodactylum tricornutum, was isolated and purified and its amino acid composition determined.

  6. The Amino Acid Composition of the Sutter's Mill Carbonaceous Chondrite

    NASA Technical Reports Server (NTRS)

    Glavin, D. P.; Burton, A. S.; Elsila, J. E.; Dworkin, J. P.; Yin, Q. Z.; Cooper, G.; Jenniskens, P.

    2012-01-01

    In contrast to the Murchison meteorite which had a complex distribution of amino acids with a total C2 to Cs amino acid abundance of approx.14,000 parts-per-billion (ppb) [2], the Sutters Mill meteorite was found to be highly depleted in amino acids. Much lower abundances (approx.30 to 180 ppb) of glycine, beta-alanine, L-alanine and L-serine were detected in SM2 above procedural blank levels indicating that this meteorite sample experienced only minimal terrestrial amino acid contamination after its fall to Earth. Carbon isotope measurements will be necessary to establish the origin of glycine and beta-alanine in SM2. Other non-protein amino acids that are rare on Earth, yet commonly found in other CM meteorites such as aaminoisobutyric acid (alpha-AIB) and isovaline, were not identified in SM2. However, traces of beta-AIB (approx.1 ppb) were detected in SM2 and could be" extraterrestrial in origin. The low abundances of amino acids in the Sutter's Mill meteorite is consistent with mineralogical evidence that at least some parts of the Sutter's Mill meteorite parent body experienced extensive aqueous and/or thermal alteration.

  7. Assessment of oil content and fatty acid composition variability in two economically important Hibiscus species.

    PubMed

    Wang, Ming Li; Morris, Brad; Tonnis, Brandon; Davis, Jerry; Pederson, Gary A

    2012-07-01

    The Hibiscus genus encompasses more than 300 species, but kenaf (Hibiscus cannabinus L.) and roselle (Hibiscus sabdariffa L.) are the two most economically important species within the genus. Seeds from these two Hibiscus species contain a relatively high amount of oil with two unusual fatty acids: dihydrosterculic and vernolic acids. The fatty acid composition in the oil can directly affect oil quality and its utilization. However, the variability in oil content and fatty acid composition for these two species is unclear. For these two species, 329 available accessions were acquired from the USDA germplasm collection. Their oil content and fatty acid composition were determined by nuclear magnetic resonance (NMR) and gas chromatography (GC), respectively. Using NMR and GC analyses, we found that Hibiscus seeds on average contained 18% oil and seed oil was composed of six major fatty acids (each >1%) and seven minor fatty acids (each <1%). Hibiscus cannabinus seeds contained significantly higher amounts of oil (18.14%), palmitic (20.75%), oleic (28.91%), vernolic acids (VA, 4.16%), and significantly lower amounts of stearic (3.96%), linoleic (39.49%), and dihydrosterculic acids (DHSA, 1.08%) than H. sabdariffa seeds (17.35%, 18.52%, 25.16%, 3.52%, 4.31%, 44.72%, and 1.57%, respectively). For edible oils, a higher oleic/linoleic (O/L) ratio and lower level of DHSA are preferred, and for industrial oils a high level of VA is preferred. Our results indicate that seeds from H. cannabinus may be of higher quality than H. sabdariffa seeds for these reasons. Significant variability in oil content and major fatty acids was also detected within both species. The variability in oil content and fatty acid composition revealed from this study will be useful for exploring seed utilization and developing new cultivars in these Hibiscus species. PMID:22703121

  8. Preparation and characterization of fatty acid ester\\/building material composites for thermal energy storage in buildings

    Microsoft Academic Search

    Ali Karaipekli; Ahmet Sar?

    2011-01-01

    In this study, fatty acid ester\\/building material composites as novel form-stable phase change materials (PCMs) were prepared by absorbing liquid fatty acid esters into porous network of conventional building materials. In the composite erythritol tetrapalmitate (ETP) and erythritol tetrastearate (ETS) esters were used as PCM for thermal energy storage, and cement and gypsum used as supporting material. The composite PCMs

  9. Rapid Procedure for the Approximate Determination of the Deoxyribonucleic Acid Base Composition of Micrococci, Staphylococci, and Other Bacteria

    Microsoft Academic Search

    SOLTI A. MEYER; KARL H. SCHLEIFER

    A simple and rapid procedure for the isolation of bacterial deoxyribonucleic acid is described. The deoxyribonucleic acid preparations are pure enough to determine the base composition by ultraviolet spectroscopy. Currently the most reliable test for the sepa- ration of staphylococci and micrococci is either an analysis of their deoxyribonucleic acid (DNA) base composition or the determination of their cell wall

  10. ZnO/carbon nano composite: Effective catalyst for the photo degradation of Acid Blue 113

    NASA Astrophysics Data System (ADS)

    Sunitha, S.; Rao, A. Nageswara; Karthikeyan, J.; Krithiga, T.

    2013-06-01

    Zinc oxide carbon composite (ZnO/C) was synthesized by self - propagating solution combustion method. This method enabled the addition of carbon insitu to the metal oxide. The composite synthesized were characterised by XRD, SEM and BET analysis. This composite was used for the removal of organic pollutants such as the dye Acid blue 113 by UV irradiation performed in a batch reactor. The influence of various experimental parameters such as the initial concentration of the dye, Concentration of the photocatalyst and the pH on the photo catalytic degradation under UV irradiation was studied. It has been observed that the degradation of the dye to be more pronounced in neutral medium. The degradation of acid blue 113 was found to increase with ZnO/C composites loading and decreases with decrease in concentration of the composite.

  11. Phospholipid fatty acid composition of hepatopancreatic brush-border membrane vesicles from the prawn Penaeus japonicus.

    PubMed

    Muriana, F J; Ruiz-Gutierrez, V; Blaya, J A; Bolufer, J

    1995-01-01

    Brush-border membrane vesicles (BBMV) were isolated from prawn hepatopancreas as we previously described (Muriana et al (1993) J Biochem 113, 625-629). The characterization of hepatopancreatic BBMV (hBBMV) by monitoring the activity of marker enzymes indicated a relatively pure apical membrane preparation reduced in basolateral contamination. Phospholipid composition of hBBMV was examined by the Iatroscan TLC/FID technique, whereas the fatty acid profile of phospholipids was examined by capillary gas chromatography. Phosphatidylcholine and phosphatidylethanolamine are the principal phospholipids of these membranes. The major fatty acids of phospholipids are palmitic (16:0), palmitoleic (16:1n-7), stearic (18:0), oleic (18:1n-9), eicosapentaenoic (20:5n-3) and docosapentaenoic (22:5n-3) acids. Individual phospholipids are characterized by distinct fatty acid compositions, but display a similar ratio of unsaturated-to-saturated fatty acids and a similar unsaturation index. PMID:7647111

  12. Fatty acid composition of some cellular membranes of fetal rat liver.

    PubMed

    Luit, H; Berger, R; Hommes, F A

    1975-01-01

    The fatty acid composition of lipids of inner mitochondrial membrane, rough and smooth endoplasmic reticulum of adult and fetal rat liver has been determined. Subcellular membranes of fetal liver show a higher content of palmitic acid and oleic acid and a lower content of stearic acid and arachidonic acid as compared to subcellular membranes of the adult liver. The activity of citrate lyase and acetyl-CoA carboxylase of rat liver cytosol has been determined as a function of age. It is concluded that the differences are due to a relative deficiency of the fatty acid elongation system. The higher degree of saturation of the fatty acids of the phospholipids of the fetal membranes may be the cause of altered permeability properties of these membranes, as illustrated by the slower rate of isoosmotic swelling in the presence of the ammonium salt of some of the Krebs cycle intermediates in fetal rat liver mitochondria. PMID:238669

  13. Determination of resin acid composition in rosin samples using cyclodextrin-modified capillary electrophoresis.

    PubMed

    Mckeon, Louise; Regan, Fiona; Burns, Barry; Leonard, Ray

    2014-10-01

    Rosins are used in a wide variety of industries in varnishes, adhesives, drug coatings, etc. In this project a novel capillary electrophoresis method was developed to investigate the resin acid composition of rosins. The acids were separated and the concentrations of individual acids present in gum rosin samples determined in order to investigate any links between the presence and concentration of these acids and the tendency of rosins to crystallize. The capillary electrophoresis method successfully separated nine resin acids in various rosin samples where previously they could not all be separated. Calibration curves were created to determine acid concentration. Abietic, dehydroabietic, neoabietic, pimaric, isopimaric, levopimaric, sandaracopimaric, palustric, and 7-oxo-dehydroabietic acids were separated using a 20 mM tris buffer at pH 9 containing 15% methanol 5 mM (2-hydroxypropyl)-?-cyclodextrin 10 mM sulfobutylether-?-cyclodextrin. Their concentrations in a crystallizing and a noncrystallizing rosin sample were determined. PMID:25066937

  14. Microbiota transplantation restores normal fecal bile acid composition in recurrent Clostridium difficile infection

    PubMed Central

    Weingarden, Alexa R.; Chen, Chi; Bobr, Aleh; Yao, Dan; Lu, Yuwei; Nelson, Valerie M.; Sadowsky, Michael J.

    2013-01-01

    Fecal microbiota transplantation (FMT) has emerged as a highly effective therapy for refractory, recurrent Clostridium difficile infection (CDI), which develops following antibiotic treatments. Intestinal microbiota play a critical role in the metabolism of bile acids in the colon, which in turn have major effects on the lifecycle of C. difficile bacteria. We hypothesized that fecal bile acid composition is altered in patients with recurrent CDI and that FMT results in its normalization. General metabolomics and targeted bile acid analyses were performed on fecal extracts from patients with recurrent CDI treated with FMT and their donors. In addition, 16S rRNA gene sequencing was used to determine the bacterial composition of pre- and post-FMT fecal samples. Taxonomic bacterial composition of fecal samples from FMT recipients showed rapid change and became similar to the donor after the procedure. Pre-FMT fecal samples contained high concentrations of primary bile acids and bile salts, while secondary bile acids were nearly undetectable. In contrast, post-FMT fecal samples contained mostly secondary bile acids, as did non-CDI donor samples. Therefore, our analysis showed that FMT resulted in normalization of fecal bacterial community structure and metabolic composition. Importantly, metabolism of bile salts and primary bile acids to secondary bile acids is disrupted in patients with recurrent CDI, and FMT corrects this abnormality. Since individual bile salts and bile acids have pro-germinant and inhibitory activities, the changes suggest that correction of bile acid metabolism is likely a major mechanism by which FMT results in a cure and prevents recurrence of CDI. PMID:24284963

  15. Electrophoretic deposition of hyaluronic acid and composite films for biomedical applications

    NASA Astrophysics Data System (ADS)

    Ma, R.; Li, Y.; Zhitomirsky, I.

    2010-06-01

    Hyaluronic acid (HYH) is a natural biopolymer, which has tremendous potential for various biomedical applications. Electrophoretic deposition (EPD) methods have been developed for the fabrication of HYH films and composites. New methods for the immobilization of drugs and proteins have been utilized for the fabrication of organic composites. Electrophoretic deposition enabled the fabrication of organic-inorganic composites containing bioceramics and bioglass in the HYH matrix. It was shown that the deposition yield, microstructure, and composition of the films can be controlled. Potential applications of EPD for the surface modification of biomedical implants and fabrication of biosensors are highlighted.

  16. Composition of antioxidants and amino acids in Stevia leaf infusions.

    PubMed

    Periche, Angela; Koutsidis, Georgios; Escriche, Isabel

    2014-03-01

    Stevia, a non-caloric natural sweetener with beneficial properties and considerable antioxidants and amino acids, is increasingly consumed as an infusion. This work evaluates the influence of the conditions (temperature: 50, 70 or 90 °C and time: 1, 5, 20 or 40 min) applied to obtain Stevia infusions, on antioxidants (total phenols, flavonoids and antioxidant activity) and amino acids. The total concentration of the eleven amino acids found was 11.70 mg/g in dried leaves and from 6.84 to 9.11 mg/g per gram of Stevia in infusions. However, infusions showed higher levels of certain amino acids (alanine, asparagine, leucine and proline), and greater values of the three antioxidant parameters in comparison with dry leaves. Temperature had more influence (minimum values at 50 °C and maximum at 90 °C) than time in the case of antioxidants. At 90 °C there were no important increases in the extraction of antioxidant compounds after 5 min; each gram of Stevia had 117 mg trolox (total antioxidant activity), 90 mg gallic acid (total phenols) and 56 mg catechin equivalents (flavonoids). Varying the temperature and time conditions no notable differences were observed in the concentrations of the majority of amino acids. However, the infusion treatment at 90 °C for 5 min was the best, as it gave the highest yield of 8 of the 11 amino acids. Therefore, with respect to the compounds analyzed in this study, the best way to obtain Stevia leaf infusions is the same as the domestic process, almost boiling water for a short time. PMID:24293005

  17. Fatty acid, amino acid, and mineral composition of four common vetch seeds on Qinghai-Tibetan plateau.

    PubMed

    Mao, Zhuxin; Fu, Hua; Nan, Zhibiao; Wan, Changgui

    2015-03-15

    The chemical composition of four common vetch (Vicia sativa L.) seeds was investigated to determine their nutrition value. The result shows that the seeds are low in lipid (1.55-2.74% of dry weight), and high in the unsaturated fatty acid (74.51-77.36% of total fatty acid). The ratio of essential amino acid to non-essential amino acid (0.62-0.69) is even higher than the amount (0.38) recommended by World Health Organization. Besides, the seeds are also found rich in Mg, Mn and Cu, but with a low ratio of Ca to P (0.24-0.73), which may increase the risk of the mineral element toxicity. The results indicate that the four common vetch seeds could be taken as an alternative food source, but the possible toxic effect should be taken into consideration. PMID:25308636

  18. Fatty acid, amino acid and trace mineral composition of Eleusine coracana (Pwana) seeds from northern Nigeria

    Microsoft Academic Search

    Diane R. Fernandez; Dorothy J. Vanderjagt; Mark Millson; Yung-Sheng Huang; Lu-Te Chuang; Andrzej Pastuszyn; Robert H. Glew

    2003-01-01

    In northern Nigeria the seeds of the cereal Eleusine coracana (finger millet), called ‘pwana’ by the Birom and ‘tamba’ by the Hausa, are used as a supplemental food taken in the form of tea or a porridge-like meal. Seeds were analyzed for fatty acid, amino acid and mineral contents. They contained 12 mg\\/g total fatty acid, 42% of which was

  19. Egg fatty acid composition from lake trout fed two Lake Michigan prey fish species.

    USGS Publications Warehouse

    Honeyfield, D.C.; Fitzsimons, J.D.; Tillitt, D.E.; Brown, S.B.

    2009-01-01

    We previously demonstrated that there were significant differences in the egg thiamine content in lake trout Salvelinus namaycush fed two Lake Michigan prey fish (alewife Alosa pseudoharengus and bloater Coregonus hoyi). Lake trout fed alewives produced eggs low in thiamine, but it was unknown whether the consumption of alewives affected other nutritionally important components. In this study we investigated the fatty acid composition of lake trout eggs when females were fed diets that resulted in different egg thiamine concentrations. For 2 years, adult lake trout were fed diets consisting of four combinations of captured alewives and bloaters (100% alewives; 65% alewives, 35% bloaters; 35% alewives, 65% bloaters; and 100% bloaters). The alewife fatty acid profile had higher concentrations of arachidonic acid and total omega-6 fatty acids than the bloater profile. The concentrations of four fatty acids (cis-13, 16-docosadienoic, eicosapentaenoic, docosapentaenoic, and docosahexaenoic acids) were higher in bloaters than in alewives. Although six fatty acid components were higher in lake trout eggs in 2001 than in 2000 and eight fatty acids were lower, diet had no effect on any fatty acid concentration measured in lake trout eggs in this study. Based on these results, it appears that egg fatty acid concentrations differ between years but that the egg fatty acid profile does not reflect the alewife-bloater mix in the diet of adults. The essential fatty acid content of lake trout eggs from females fed alewives and bloaters appears to be physiologically regulated and adequate to meet the requirements of developing embryos.

  20. Chemical composition and physicochemical and hydrogenation characteristics of high-palmitic acid solin (low-linolenic acid flaxseed) oil

    Microsoft Academic Search

    F. S. Hosseinian; G. G. Rowland; P. R. Bhirud; J. H. Dyck; R. T. Tyler

    2004-01-01

    The physicochemical characteristics and FA compositions were determined for refined-bleached-deodorized (RBD) high-palmitic\\u000a acid solin (HPS) oil, RBD solin oil, and degummed linseed oil. The predominant FA in HPS oil were palmitic (16.6%), palmitoleic\\u000a (1.4%), stearic (2.5%), oleic (11.3%), linoleic (63.7%), and linolenic (3.4%). HPS oil was substantially higher in palmitic\\u000a acid than either solin oil or linseed oil, and similar

  1. Chemical composition of acid rains in the Venezuelan savannah region

    Microsoft Academic Search

    E. Sanhueza; M. C. Arias; L. Donoso; N. Graterol; M. Hermoso; I. Martí; J. Romero; A. Rondón; M. Santana

    1992-01-01

    The chemical composition of rain events has been determined at 6 sites in the Venezuelan savannah region. The results indicate that precipitations are little affected by anthropogenic emissions and that rain concentrations of anions and cations are similar to those observed at \\

  2. Thermoformed protein based composites in presence of organic acids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    World industrialization has generated substantial quantities of petroleum-based plastics over many years, which are non biodegradable. There is a growing demand for the use of renewable agricultural sources to develop eco-friendly biobased composites. Agriculture-sourced proteins and starches are b...

  3. Persistent biases in the amino acid composition of prokaryotic proteins

    Microsoft Academic Search

    Géraldine Pascal; Claudine Médigue; Antoine Danchin

    2006-01-01

    Summary Correspondence analysis of 28 proteomes selected to span the entire realm of prokaryotes revealed universal biases in the proteins' amino acid distribution. Integral Inner Membrane Proteins always form an individual cluster, which can then be used to predict protein localisation in unknown proteomes, independently of the organism's biotope or kingdom. Orphan proteins are consistently rich in aromatic residues. Another

  4. Photoproducts of carminic acid formed by a composite from Manihot dulcis waste.

    PubMed

    Antonio-Cisneros, Cynthia M; Dávila-Jiménez, Martín M; Elizalde-González, María P; García-Díaz, Esmeralda

    2015-04-15

    Carbon-TiO2 composites were obtained from carbonised Manihot dulcis waste and TiO2 using glycerol as an additive and thermally treating the composites at 800 °C. Furthermore, carbon was obtained from manihot to study the adsorption, desorption and photocatalysis of carminic acid on these materials. Carminic acid, a natural dye extracted from cochineal insects, is a pollutant produced by the food industry and handicrafts. Its photocatalysis was observed under different atmospheres, and kinetic curves were measured by both UV-Vis and HPLC for comparison, yielding interesting differences. The composite was capable of decomposing approximately 50% of the carminic acid under various conditions. The reaction was monitored by UV-Vis spectroscopy and LC-ESI-(Qq)-TOF-MS-DAD, enabling the identification of some intermediate species. The deleterious compound anthracene-9,10-dione was detected both in N2 and air atmospheres. PMID:25466082

  5. Prebiotic syntheses of vitamin coenzymes: II. Pantoic acid, pantothenic acid, and the composition of coenzyme A

    NASA Technical Reports Server (NTRS)

    Miller, S. L.; Schlesinger, G.

    1993-01-01

    Pantoic acid can by synthesized in good prebiotic yield from isobutyraldehyde or alpha-ketoisovaleric acid + H2CO + HCN. Isobutyraldehyde is the Strecker precursor to valine and alpha-ketoisovaleric acid is the valine transamination product. Mg2+ and Ca2+ as well as several transition metals are catalysts for the alpha-ketoisovaleric acid reaction. Pantothenic acid is produced from pantoyl lactone (easily formed from pantoic acid) and the relatively high concentrations of beta-alanine that would be formed on drying prebiotic amino acid mixtures. There is no selectivity for this reaction over glycine, alanine, or gamma-amino butyric acid. The components of coenzyme A are discussed in terms of ease of prebiotic formation and stability and are shown to be plausible choices, but many other compounds are possible. The gamma-OH of pantoic acid needs to be capped to prevent decomposition of pantothenic acid. These results suggest that coenzyme A function was important in the earliest metabolic pathways and that the coenzyme A precursor contained most of the components of the present coenzyme.

  6. Determination of fatty acid composition of ?-irradiated hazelnuts, walnuts, almonds, and pistachios

    NASA Astrophysics Data System (ADS)

    Gecgel, Umit; Gumus, Tuncay; Tasan, Murat; Daglioglu, Orhan; Arici, Muhammet

    2011-04-01

    Hazelnut, walnut, almonds, and pistachio nuts were treated with 1, 3, 5, and 7 kGy of gamma irradiation, respectively. Oil content, free fatty acid, peroxide value, and fatty acid composition of the nuts were investigated immediately after irradiation. The data obtained from the experiments indicated that gamma irradiation did not cause any significant change in the oil content of nuts. In contrast, free fatty acid and peroxide value of the nuts increased proportionally to the dose (p<0.05). Among the fatty acids determined, the concentration of total saturated fatty acids increased while total monounsaturated and total polyunsaturated fatty acids decreased with the irradiation dose (p<0.05 and <0.01).

  7. Stable carbon isotopic compositions of organic acids in total suspended particles and dusts from Guangzhou, China

    NASA Astrophysics Data System (ADS)

    Ma, Shexia; Peng, Ping'an; Song, Jianzhong; Zhao, Jinping; He, Lulu; Sheng, Guoying; Fu, Jiamo

    2010-10-01

    Stable carbon isotopic compositions of individual organic acids were determined in total suspended particles and dusts from Guangzhou. The ? 13C values of high molecular weight n-alkanoic acids (C 20-C 28) varied from -34.1‰ to -32.4‰ and tended to be heavier in summer and lighter in winter. These ? 13C values indicate that high molecular weight n-alkanoic acids were derived mainly from emission by C 3 plants. Reduced biological synthesis of high molecular weight n-alkanoic acids in winter may be the reason for the light carbon isotopic composition. The ? 13C values of low molecular weight n-alkanoic acids (C 10-C 18) changed from -31.7‰ to -30.3‰ and exhibited a reverse seasonal trend, i.e., heavier in winter and lighter in summer. Slightly heavier ? 13C values of low molecular weight n-alkanoic acids than those of high molecular weight n-alkanoic acids suggested that they may be emitted from blended sources, e.g., anthropogenic sources and vegetation waxes. Lighter ? 13C values in summer may be attributed to relatively low anthropogenic sources and high botanic sources in summer. Dicarboxylic acids and aromatic acids have been proposed as secondary products from photochemical degradation. The average ? 13C values of dicarboxylic acids and aromatic acids were heavier, and ranged from -25.2‰ to -22.9‰ and from -30.0‰ to -27.6‰, respectively. Both dicarboxylic acids and aromatic acids displayed the same temporal variations in the ? 13C values, i.e., negative ? 13C in the summer samples and positive in the winter samples, which may be controlled by photochemical reactions; they are generally severe in winter in Guangzhou under the monsoon weather system. The heaviest ? 13C values were observed in dicarboxylic acids, indicating that dicarboxylic acids were formed by fast and more complete oxidation reactions. These results indicate that the stable carbon isotopic composition of organic acids may provide important information about sources and photochemical reactions of organic matter in the atmosphere.

  8. Effect of acidic solutions on the surface degradation of a micro-hybrid composite resin.

    PubMed

    Münchow, Eliseu A; Ferreira, Ana Cláudia A; Machado, Raissa M M; Ramos, Tatiana S; Rodrigues-Junior, Sinval A; Zanchi, Cesar H

    2014-01-01

    Composite resins may undergo wear by the action of chemical substances (e.g., saliva, alcohol, bacterial acids) of the oral environment, which may affect the material's structure and surface properties. This study evaluated the effect of acidic substances on the surface properties of a micro-hybrid composite resin (Filtek Z-250). Eighty specimens were prepared, and baseline hardness and surface roughness (KMN0 and Ra0, respectively) were measured. The specimens were subjected to sorption (SO) and solubility (SL) tests according to ISO 4049:2009, but using different storage solutions: deionized water; 75/25 vol% ethanol/water solution; lactic acid; propionic acid; and acetic acid. The acids were used in two concentrations: PA and 0.02 N. pH was measured for all solutions and final hardness (KMN1) and surface roughness (Ra1) were measured. Data were analyzed with paired t-tests and one-way ANOVA and Tukey's test (a=5%). All solutions decreased hardness and increased the Ra values, except for the specimens stored in water and 0.02 N lactic acid, which maintained the hardness. All solutions produced similar SO and SL phenomena, except for the 0.02 N lactic acid, which caused lower solubility than the other solutions. Ethanol showed the highest pH (6.6) and the 0.02 N lactic acid the lowest one (2.5). The solutions affected negatively the surface properties of the composite resin; in addition, an acidic pH did not seem to be a significant factor that intensifies the surface degradation phenomena. PMID:25250496

  9. Decreased hepatotoxic bile acid composition and altered synthesis in progressive human nonalcoholic fatty liver disease

    SciTech Connect

    Lake, April D. [University of Arizona, Department of Pharmacology and Toxicology, Tucson, AZ 85721 (United States); Novak, Petr [Biology Centre ASCR, Institute of Plant Molecular Biology, Ceske Budejovice 37001 (Czech Republic); Shipkova, Petia; Aranibar, Nelly; Robertson, Donald; Reily, Michael D. [Pharmaceutical Candidate Optimization, Bristol-Myers Squibb Co., Princeton, NJ 08543 (United States); Lu, Zhenqiang [The Arizona Statistical Consulting Laboratory, University of Arizona, Tucson, AZ 85721 (United States); Lehman-McKeeman, Lois D. [Pharmaceutical Candidate Optimization, Bristol-Myers Squibb Co., Princeton, NJ 08543 (United States); Cherrington, Nathan J., E-mail: cherrington@pharmacy.arizona.edu [University of Arizona, Department of Pharmacology and Toxicology, Tucson, AZ 85721 (United States)

    2013-04-15

    Bile acids (BAs) have many physiological roles and exhibit both toxic and protective influences within the liver. Alterations in the BA profile may be the result of disease induced liver injury. Nonalcoholic fatty liver disease (NAFLD) is a prevalent form of chronic liver disease characterized by the pathophysiological progression from simple steatosis to nonalcoholic steatohepatitis (NASH). The hypothesis of this study is that the ‘classical’ (neutral) and ‘alternative’ (acidic) BA synthesis pathways are altered together with hepatic BA composition during progression of human NAFLD. This study employed the use of transcriptomic and metabolomic assays to study the hepatic toxicologic BA profile in progressive human NAFLD. Individual human liver samples diagnosed as normal, steatosis, and NASH were utilized in the assays. The transcriptomic analysis of 70 BA genes revealed an enrichment of downregulated BA metabolism and transcription factor/receptor genes in livers diagnosed as NASH. Increased mRNA expression of BAAT and CYP7B1 was observed in contrast to decreased CYP8B1 expression in NASH samples. The BA metabolomic profile of NASH livers exhibited an increase in taurine together with elevated levels of conjugated BA species, taurocholic acid (TCA) and taurodeoxycholic acid (TDCA). Conversely, cholic acid (CA) and glycodeoxycholic acid (GDCA) were decreased in NASH liver. These findings reveal a potential shift toward the alternative pathway of BA synthesis during NASH, mediated by increased mRNA and protein expression of CYP7B1. Overall, the transcriptomic changes of BA synthesis pathway enzymes together with altered hepatic BA composition signify an attempt by the liver to reduce hepatotoxicity during disease progression to NASH. - Highlights: ? Altered hepatic bile acid composition is observed in progressive NAFLD. ? Bile acid synthesis enzymes are transcriptionally altered in NASH livers. ? Increased levels of taurine and conjugated bile acids are observed in NASH. ? Hepatic bile acid synthesis shifts toward the alternative pathway in NASH.

  10. Composites of manganese oxide with carbon materials as catalysts for the ozonation of oxalic acid.

    PubMed

    Orge, C A; Órfão, J J M; Pereira, M F R

    2012-04-30

    Manganese oxide and manganese oxide-carbon composites were prepared and tested as catalysts for the removal of oxalic acid by ozonation. Their performances were compared with the parent carbon material (activated carbon or carbon xerogel) used to prepare the composites. Oxalic acid degradation by carbon materials is slower than that attained with manganese oxide or manganese oxide-carbon composites. A complete degradation after 90 and 45 min of reaction was obtained for carbon materials and for the catalysts containing manganese, respectively. The ozonation in the presence of the prepared composites are supposed to occur mainly by surface reactions, following a direct oxidation mechanism by molecular ozone and/or surface oxygenated radicals. PMID:22341747

  11. Dependence of fatty-acid composition of edible oils on their enrichment in olive phenols.

    PubMed

    Girón, María Victoria; Ruiz-Jiménez, José; Luque de Castro, María Dolores

    2009-04-01

    Olive phenol extracts from waste from olive-oil production (alperujo) have been obtained by microwave-assisted extraction and used for edible oil enrichment. The extracts as such or after extractant removal were used to enrich edible oils of different fatty acid composition by liquid-liquid or solid-liquid extraction, respectively. The distribution ratios of the phenols in the different oils [olive-orujo (the waste of milled olives from which low-quality oil is obtained), sunflower, high oleic-acid content sunflower, coconut, and linseed] showed a given order as a function of phenol polarity and molecular weight, with higher distribution factors for more polar and lower molecular-weight phenols. Concerning oil composition, those oils with higher concentration of polyunsaturated fatty acids yielded higher phenol distribution factors; oils with higher concentrations of saturated fatty acids yielded lower distribution factors. PMID:19253972

  12. The effects of dietary trans, trans methyl octadecadienoate acid on composition and fatty acids of rat heart1'2

    Microsoft Academic Search

    Peter H. Yu; John E. Kinsella

    Traits, trans linoleate (18:2) as the sole source of dietary fat (10% of calories) for 12 weeks induced the typical symptoms of essential fatty acid deficiency in rats and markedly altered the gross and lipid composition of hearts. The cardiac protein and phospholipids were decreased compared to rats receiving adequate cis, cis linoleate, i.e., 180.0 and 18.5 versus 214.4 and

  13. Effects of dietary fish oil on fatty acid composition and flavor of channel catfish 

    E-print Network

    Haynes, Kellie Cecile

    1989-01-01

    EFFECTS OF DIETARY FISH OIL ON FATTY ACID COMPOSITION AND FLAVOR OF CHANNEL CATFISH A Thesis by KELLIE CECILE HAYNES Submitted to the Office of Graduate Studies of Texas A8M University in partial fulfilment of the requirements for the degree... of MASTER OF SCIENCE December 1989 Major Subject: Food Science and Technology EFFECTS OF DIETARY FISH OIL ON FATTY ACID COMPOSITION AND FLAVOR OF CHANNEL CATFISH A thesis by KELLIE CECILE HAYNES Approved as to style and content by: J myT Ke...

  14. Dietary n-3 polyunsaturated fatty acids modify fatty acid composition in hepatic and abdominal adipose tissue of sucrose-induced obese rats

    Microsoft Academic Search

    Alfonso Alexander-Aguilera; Silvia Berruezo; Guillermo Hernández-Diaz; Ofelia Angulo; Rosamaria Oliart-Ros

    The fatty acid profile of hepatocytes and adipocytes is determined by the composition of the dietary lipids. It remains unclear\\u000a which fatty acid components contribute to the development or reduction of insulin resistance. The present work examined the\\u000a fatty acid composition of both tissues in sucrose-induced obese rats receiving fish oil to determine whether the effect of\\u000a dietary (n-3) polyunsaturated

  15. General characteristics of Pinus spp. Seed fatty acid compositions, and importance of ?5-olefinic acids in the taxonomy and phylogeny of the genus

    Microsoft Academic Search

    Robert L. Wolff; Frédérique Pédrono; Elodie Pasquier; Anne M. Marpeau

    2000-01-01

    The ?5-unsaturated polymethylene-interrupted fatty acid (?5-UPIFA) contents and profiles of gymnosperm seeds are useful chemometric\\u000a data for the taxonomy and phylogeny of that division, and these acids may also have some biomedical or nutritional applications.\\u000a We recapitulate here all data available on pine (Pinus; the largest genus in the family Pinaceae) seed fatty acid (SFA) compositions, including 28 unpublished compositions.

  16. Development and characterization of chitosan and phosphomolybdic acid (PMA) based composites

    Microsoft Academic Search

    R. K. Mishra; S. Mondal; M. Datt; Ajit K. Banthia

    2010-01-01

    This work reports the development and characterization of chitosan\\/Phosphomolybdic acid (PMA) based composite membranes. The\\u000a prepared composite membranes were characterized by FTIR (Fourier transform infrared) spectroscopy, X ray diffraction (XRD),\\u000a differential scanning calorimetry (DSC), tensile strength test, and thermogravimetric analysis (TGA). FTIR spectroscopy indicated\\u000a the proper molecular interactions between chitosan and PMA. XRD spectroscopy indicated the semi crystalline nature of

  17. Fatty acid composition and its relationship with physicochemical properties of pecan ( Carya illinoensis ) oil

    Microsoft Academic Search

    J. F. Toro-Vazquez; M. A. Charó-Alonso; F. Pérez-Briceño

    1999-01-01

    The composition and physicochemical properties of pecan (Carya illinoensis) kernels and oils from different native trees of the central region of Mexico were investigated. The main compositional characteristic\\u000a of the kernel was the high lipid content (70–79% w\\/w on dry basis) with elevated concentration of oleic acid (55–75% w\\/w).\\u000a The results confirmed the relationship in the biosynthesis of linoleic and

  18. Effects of diet, age and gender on the polyunsaturated fatty acid composition of broiler anatomical compartments

    Microsoft Academic Search

    R. Poureslami; K. Raes; G. Huyghebaert; S. De Smet

    2010-01-01

    1.?The objective of this study was to investigate the effect of dietary fatty acid (FA) composition, age, and gender on the FA composition of different broiler anatomical compartments. Four dietary fat sources (palm fat, P; soybean oil, S; linseed oil, L; fish oil, F) were added to a wheat–soybean meal based diet at 30 g\\/kg in addition to 50 g\\/kg

  19. Structure and mechanical properties of jute—polylactic acid biodegradable composites

    Microsoft Academic Search

    Hongwei Ma; Chang Whan Joo

    2011-01-01

    In this study, biodegradable composites based on jute and polylactic acid (PLA) were prepared by a film-stacking process. The effect of jute fiber content, processing temperature, and alkali treatment on the structure and mechanical properties of jute—PLA composites were investigated. The interfacial structure between jute fibers and PLA was analysed by scanning electron microscope. The optimum tensile properties of jute—PLA

  20. Seasonal distribution and fatty acid composition of littoral microalgae in the Yenisei River

    Microsoft Academic Search

    Nadezhda N. Sushchik; Michail I. Gladyshev; Elena A. Ivanova; Elena S. Kravchuk

    2010-01-01

    We studied fatty acid (FA) composition of littoral microalgae in the fast-flowing oligotrophic river, the Yenisei, Siberia,\\u000a monthly for 3 years. Seasonal dynamics of species composition had similar patterns in all the studied years. In springs, a\\u000a pronounced dominance of filamentous green algae occurred, in summer and autumn diatoms were abundant, and in late autumn and\\u000a winter epilithic biofilms consisted primarily

  1. Organic matter characteristics in a Mediterranean stream through amino acid composition: changes driven by intermittency

    Microsoft Academic Search

    Irene YllaIsis; Isis Sanpera-Calbet; Isabel Muñoz; Anna M. Romaní; Sergi Sabater

    Amino acid composition (quality) and abundance (quantity) of organic matter (OM) in an intermittent Mediterranean stream were\\u000a followed during transitions from wet to dry and dry to wet conditions. Amino acids were analyzed in benthic material (epilithic\\u000a biofilms, sand sediments, leaf material) as well as in the flowing water (dissolved organic matter, DOM). A principal component\\u000a analysis and the estimation

  2. Nanocellulose reinforced PVA composite films: Effects of acid treatment and filler loading

    Microsoft Academic Search

    Sun-Young Lee; D. Jagan Mohan; In-Aeh Kang; Geum-Hyun Doh; Soo Lee; Seong Ok Han

    2009-01-01

    Nanocellulose was prepared by acid hydrolysis of microcrystalline cellulose (MCC) at different hydrobromic acid (HBr) concentrations.\\u000a Polyvinyl alcohol (PVA) composite films were prepared by the reinforcement of nanocellulose into a PVA matrix at different\\u000a filler loading levels and subsequent film casting. Chemical characterization of nanocelluloses was performed for the analysis\\u000a of crystallinity (Xc), degree of polymerization (DP), and molecular weight

  3. Tables of critical values for examining compositional non-randomness in proteins and nucleic acids

    NASA Technical Reports Server (NTRS)

    Laird, M.; Holmquist, R.

    1975-01-01

    A binomially distributed statistic is defined to show whether or not the proportion of a particular amino acid in a protein deviates from random expectation. An analogous statistic is derived for nucleotides in nucleic acids. These new statistics are simply related to the classical chi-squared test. They explicitly account for the compositional fluctuations imposed by the finite length of proteins, and they are more accurate than previous tables.

  4. Fatty acid composition of heart cells exposed to thermally oxidized fats

    Microsoft Academic Search

    R. P. Bird; J. C. Alexander

    1979-01-01

    Corn oil and olive oil were thermally oxidized, and the free fatty acids from the fresh fats, and from the distillable non-urea-adductable\\u000a (DNUA) fractions of the thermally oxidized fats were prepared. These were added as emulsions to the medium of primary cultures\\u000a of heart endothelial and muscle cells from neonatal rats. After exposure for 24 hr, the fatty acid composition

  5. Feeding feedlot steers fish oil alters the fatty acid composition of adipose and muscle tissue

    Microsoft Academic Search

    T. J. Wistuba; E. B. Kegley; J. K. Apple; D. C. Rule

    2007-01-01

    Sixteen steers (441±31.7kg initial body weight) consumed two high concentrate diets with either 0 or 3% fish oil to determine the impact of fish oil, an omega-3 fatty acid source, on the fatty acid composition of beef carcasses. Collected tissue samples included the Longissimus thoracis from the 6th to 7th rib section, ground 10th to 12th rib, liver, subcutaneous adipose

  6. Stearoyl-Coenzyme A Desaturase Gene Polymorphism and Milk Fatty Acid Composition in Italian Holsteins

    Microsoft Academic Search

    M. Mele; G. Conte; B. Castiglioni; S. Chessa; N. P. P. Macciotta; A. Serra; A. Buccioni; G. Pagnacco; P. Secchiari

    2007-01-01

    Milk fatty acid composition is a parameter of great interest for evaluation of nutritional quality of milk. Stearoyl-CoA desaturase (SCD) is a key enzyme in mammary lipid metabolism because it is able to add a double bond in the cis ?9-position in a large spectrum of medium- and long-chain fatty acids. A polymorphism with 2 alleles (A and V) in

  7. Dietary sandalwood seed oil modifies fatty acid composition of mouse adipose tissue, brain, and liver

    Microsoft Academic Search

    Yandi Liu; Robert B. Longmore

    1997-01-01

    Sandalwood (Santalum spicatum) seed oil, which occurs to about 50% of the weight of the seed kernels, contains 30–35% of total fatty acids (FA) as ximenynic\\u000a acid (XMYA). This study was designed to obtain basic information on changes in tissue FA composition and on the metabolic\\u000a fate of XMYA in mice fed a sandalwood seed oil (SWSO)-enriched diet. Female mice

  8. Effect of diet on the fatty acid and molecular species composition of dog retina phospholipids

    Microsoft Academic Search

    Isabelle Delton-Vandenbroucke; Maureen B. Maude; Huiming Chen; Gustavo D. Aguirre; Gregory M. Acland; Robert E. Anderson

    1998-01-01

    Dogs were born to mothers fed commercial diets low or enriched in n-3 fatty acids and raised on those diets until they were\\u000a about 50 d old. Retinas were removed, lipids were extracted, and total phospholipids were anlyzed for fatty acid and molecular\\u000a species composition. Animals from the low n-3 group had significantly lower retinal levels of 22?6n-3 and higher

  9. Effect of dietary selenium and omega-3 fatty acids on muscle composition and quality in broilers

    Microsoft Academic Search

    Anna Haug; Susanne Eich-Greatorex; Aksel Bernhoft; Jens P Wold; Harald Hetland; Olav A Christophersen; Trine Sogn

    2007-01-01

    BACKGROUND: Human health may be improved if dietary intakes of selenium and omega-3 fatty acids are increased. Consumption of broiler meat is increasing, and the meat content of selenium and omega-3 fatty acids are affected by the composition of broiler feed. A two-way analyses of variance was used to study the effect of feed containing omega-3 rich plant oils and

  10. Developmental changes in the fatty acid composition and cholesterol content of chicken heart plasma membrane

    Microsoft Academic Search

    Howard Kutchai; Thomas F. Ross; David M. Dunning; Marsha Martin; Susan L. King

    1978-01-01

    1.The fatty acid composition and cholesterol\\/phospholipid molar ratio of lipids extracted from subcellular fractions of 5–6, 10, and 20 day chick embryo heart and from adult chicken heart were determined.2.The fraction of saturated fatty acids decreases steadily during embryonic and post-hatching development.3.The cholesterol\\/phospholipid molar ratio decreases between 5–6 and 10 days of embryonic life, increases somewhat between 10 and 20

  11. Breeding for modified fatty acid composition via experimental mutagenesis in Camelina sativa (L.) Crtz

    Microsoft Academic Search

    A Büchsenschütz-Nothdurft; A Schuster; W Friedt

    1998-01-01

    Camelina sativa (L.) Crtz. is a potential oil crop for non-food industrial applications. Seeds of the German C. sativa cultivar Lindo were mutagenically treated with ethyl methanesulfonate (EMS) in order to modify the fatty acid composition in the seed oil and to select mutants with either reduced or increased linolenic acid (C18:3) content, respectively. The M2-generation was evaluated for fatty

  12. Glass Fiber Reinforced Epoxy Resin-m-Amino Benzoic Acid Composites

    Microsoft Academic Search

    J. R. Thakkar

    1995-01-01

    The curing behaviour of epoxy resin-m-amino benzoic acid, the condensation product of epoxy resin namely; diglycidyl ether of bisphenol-A (DGEBA) and m-amino benzoic acid (m-ABA) was studied by differential scanning calaorimetry (DSC). The resultant neat products of DGEBA-m-ABA were characterised by infrared (IR) spectral studies and thermogravimetric analysis (TGA). The glass fiber reinforced composites were prepared and evaluated for their

  13. The composition of coffee oil and its component fatty acids

    Microsoft Academic Search

    N. A. Khan; J. B. Brown

    1953-01-01

    Summary  A specimen of coffee oil has been examined with the objective of determining its composition in the light of possible uses\\u000a of the oil which is recoverable as a byproduct in the soluble coffee industry. The oil, as obtained by extraction of the coffee\\u000a grounds with solvent, contains over 5% of unique unsaponifiable material which, without preliminary removal, makes the

  14. Interaction of Dietary Protein and Alpha-Linolenic Acid on Polyunsaturated Fatty Acid Composition of Liver Microsomal Phospholipids and Eicosanoid Production in Streptozotocin-lnduced Diabetic Rats

    Microsoft Academic Search

    Akira Ikeda; Michihiro Sugano

    1993-01-01

    The effect of dietary protein, either casein (CAS) or soybean protein (SOY), on the polyunsaturated fatty acid (PUFA) composition of liver microsomal phospholipids and eicosanoid production was compared in normal and streptozotocin-induced diabetic rats fed diets containing perilla oil rich in ?-linolenic acid. In normal rats the linoleic acid desaturation index in liver microsomal phospholipids was significantly higher in the

  15. Fatty acid composition of resynthesized Brassica napus L., B. campestris L. and B. alboglabra Bailey with special reference to the inheritance of erucic acid content

    Microsoft Academic Search

    B Y Chen; W K Heneen

    1989-01-01

    The fatty acid composition of the oil of four resynthesized rapeseed (Brassica napus L.) lines resulting from crosses between B. campestris L. and B. alboglabra Bailey was compared with that of the mid-parent value. Low palmitic acid content was partially epistatic over high. High oleic acid content could be either partially hypostatic to or transgressively epistatic over low content of

  16. Amino acid composition and antioxidant activities of hydrolysates and peptide fractions from porcine collagen.

    PubMed

    Ao, Jing; Li, Bo

    2012-10-01

    The amino acid composition and antioxidant activities of different hydrolysates from porcine collagen were analyzed. The gelatin was hydrolyzed for antioxidative peptides with various proteases, namely papain, protease from bovine pancreas, protease from Streptomyces, and cocktail mixture of protease from bovine pancreas and protease from Streptomyces. The hydrolysates were assessed using methods of DPPH radical-scavenging ability, metal-chelating ability and lipid peroxidation inhibition activity. It was found that the collagen hydrolysates by different protease treatments had different amino acid compositions and antioxidant properties. However, the contents of Hyp and Pro were improved and the content of Gly was decreased in each collagen hydrolysate compared with collagen. The hydrolysate prepared with the cocktail mixture of proteases, which exhibited the highest antioxidant activity, was separated into 6 fractions by gel filtration chromatography. Fraction 2 was further separated by ion exchange chromatography. Fraction 2b with abundant basic amino acids and Fraction 2d which was slightly acidic fractions had higher radical-scavenging and metal-chelating activities, and both Fraction 2b and 2d contained more hydrophobic amino acids. The results confirmed that the antioxidative peptides were rich in Hyp, Pro and Gly, which accounted for half of amino acid composition. This article added further support to the preparation of natural antioxidative peptides from porcine skin collagen. PMID:23064526

  17. Influence of dietary lipid source and strain on fatty acid composition of Muscovy duck meat.

    PubMed

    Schiavone, A; Romboli, I; Chiarini, R; Marzoni, M

    2004-04-01

    A trial was conducted to study the effect of dietary 2% soya bean oil and dietary 2% fish oil (FO) on fatty acid composition of breast meat of two different Muscovy duck (Cairina moschata domestica L.) strains. The two strains were a broiler strain selected for meat production and an unselected rural strain. Fatty acid composition of breast muscle was deeply influenced by lipid source. Dietary FO improved the long chain polyunsaturated fatty acids (LC-PUFAs) of omega 3 series content, while the content of LC-PUFAs of omega 6 series was reduced. Differences in susceptibility in lipid manipulation were found between the two groups of animals suggesting the highest capability of animals belonging to the rural strain in stocking arachidonic acid in breast muscle. As the fatty acid profile of Muscovy duck meat can be considerably modified by changing the fatty acid composition of the diet, and dietary FO represents an easy way to reach this goal, human intake of healthy n-3 LC-PUFAs could be enhanced using this enriched poultry meat, even if the influence of FO on organoleptic characteristics (i.e. off-flavours) must be evaluated. PMID:15059231

  18. Effects of diets high in saturated fatty acids, canola oil, or safflower oil on platelet function, thromboxane B2 formation, and fatty acid composition of platelet phosphoIipids?3

    Microsoft Academic Search

    Jong-Sook Kwon; Jean T Snook; Gordon M Wardlaw; Daniel H Hwang

    Platelet function and fatty acid composition were investigated in 30 healthy male subjects who ate a con- trolled-saturated-fatty-acid (baseline) diet far 3 wk and then consumed either safflower oil or canola oil as a major fat source for 8 wk. Fatty acid composition of platelet phospholipids re- flected changes in dietary fatty acid composition. Compared with baseline a 35% decrease

  19. Dietary trans-10, cis-12-conjugated linoleic acid alters fatty acid metabolism and microbiota composition in mice.

    PubMed

    Marques, Tatiana M; Wall, Rebecca; O'Sullivan, Orla; Fitzgerald, Gerald F; Shanahan, Fergus; Quigley, Eamonn M; Cotter, Paul D; Cryan, John F; Dinan, Timothy G; Ross, R Paul; Stanton, Catherine

    2015-03-14

    The main aim of the present study was to investigate the effects of dietary trans-10, cis-12-conjugated linoleic acid (t10c12-CLA) on intestinal microbiota composition and SCFA production. C57BL/6 mice (n 8 per group) were fed a standard diet either supplemented with t10c12-CLA (0·5 %, w/w) (intervention) or with no supplementation (control), daily for 8 weeks. Metabolic markers (serum glucose, leptin, insulin and TAG, and liver TAG) were assessed by ELISA commercial kits, tissue long-chain fatty acids and caecal SCFA by GC, and microbial composition by 16S rRNA pyrosequencing. Dietary t10c12-CLA significantly decreased visceral fat mass (P< 0·001), but did not affect body weight (intervention), when compared with no supplementation (control). Additionally, lipid mass and composition were affected by t10c12-CLA intake. Caecal acetate, propionate and isobutyrate concentrations were higher (P< 0·05) in the t10c12-CLA-supplemented group than in the control group. The analysis of the microbiota composition following 8 weeks of t10c12-CLA supplementation revealed lower proportions of Firmicutes (P= 0·003) and higher proportions of Bacteroidetes (P= 0·027) compared with no supplementation. Furthermore, t10c12-CLA supplementation for 8 weeks significantly altered the gut microbiota composition, harbouring higher proportions of Bacteroidetes, including Porphyromonadaceae bacteria previously linked with negative effects on lipid metabolism and induction of hepatic steatosis. These results indicate that the mechanism of dietary t10c12-CLA on lipid metabolism in mice may be, at least, partially mediated by alterations in gut microbiota composition and functionality. PMID:25697178

  20. Discrimination of acidic and alkaline enzyme using Chou's pseudo amino acid composition in conjunction with probabilistic neural network model.

    PubMed

    Khan, Zaheer Ullah; Hayat, Maqsood; Khan, Muazzam Ali

    2015-01-21

    Enzyme catalysis is one of the most essential and striking processes among of all the complex processes that have evolved in living organisms. Enzymes are biological catalysts, which play a significant role in industrial applications as well as in medical areas, due to profound specificity, selectivity and catalytic efficiency. Refining catalytic efficiency of enzymes has become the most challenging job of enzyme engineering, into acidic and alkaline. Discrimination of acidic and alkaline enzymes through experimental approaches is difficult, sometimes impossible due to lack of established structures. Therefore, it is highly desirable to develop a computational model for discriminating acidic and alkaline enzymes from primary sequences. In this study, we have developed a robust, accurate and high throughput computational model using two discrete sample representation methods Pseudo amino acid composition (PseAAC) and split amino acid composition. Various classification algorithms including probabilistic neural network (PNN), K-nearest neighbor, decision tree, multi-layer perceptron and support vector machine are applied to predict acidic and alkaline with high accuracy. 10-fold cross validation test and several statistical measures namely, accuracy, F-measure, and area under ROC are used to evaluate the performance of the proposed model. The performance of the model is examined using two benchmark datasets to demonstrate the effectiveness of the model. The empirical results show that the performance of PNN in conjunction with PseAAC is quite promising compared to existing approaches in the literature so for. It has achieved 96.3% accuracy on dataset1 and 99.2% on dataset2. It is ascertained that the proposed model might be useful for basic research and drug related application areas. PMID:25452135

  1. Opportunities of deoxyribonucleic acid complexes composites for nonlinear optical applications

    NASA Astrophysics Data System (ADS)

    Sahraoui, B.; Pranaitis, M.; Gindre, D.; Niziol, J.; Kažukauskas, V.

    2011-10-01

    In this paper, we illustrate new functionalities for nonlinear optical applications of bio-molecular systems. This study presents DNA complex with new ionic surfactants. These surfactants enabled DNA solubility in solvents other than alcohols, like aromatic and chlorinated ones. Composites with two nonlinear optical (NLO) active dyes are subjects of the second and third harmonic generation experiments. The found effective nonlinear susceptibilities values are much higher than that for standard fused silica. We also demonstrate any influence of the surfactant on NLO properties.

  2. Modifying yolk fatty acid composition to improve the health quality of shell eggs 

    E-print Network

    Van Elswyk, Mary Elizabeth

    1990-01-01

    is the seed oil of plants such as corn and safflower. In both animals and humans, linoleic acid, through a process of elongation and desaturation, yields arachidonic acid (20:4n-6). Arachidonic acid serves as a precursor for the synthesis of eicosanoids... to improving the health quality of shell eggs. In this study, effects of a laying hen diet enriched with 3% menhaden oil (test diet) versus a control diet (no added fat) on egg yolk composition, egg production parameters, and egg sensory characteristics...

  3. The SNPs in the ACACA gene are effective on fatty acid composition in Holstein milk.

    PubMed

    Matsumoto, Hirokazu; Sasaki, Kenta; Bessho, Takuya; Kobayashi, Eiji; Abe, Tsuyoshi; Sasazaki, Shinji; Oyama, Kenji; Mannen, Hideyuki

    2012-09-01

    Fatty acid composition is an important economic trait for both dairy and beef cattle and controlled by genetic factors. Candidate genes controlling fatty acid composition may be found in fat synthesis and metabolism pathways. Acetyl-CoA carboxylase is the flux-determining enzyme in the regulation of fatty acid synthesis in animal tissues. One of two isozymes of this enzyme, acetyl-CoA carboxylase-? (ACACA), catalyses the first committed step of fatty acid synthesis in mammalian cytosol, leading to the biosynthesis of long-chain fatty acids. In the current study, the sequence comparison of the coding sequence (CDS) and two promoter regions (PIA and PIII) in bovine ACACA gene was performed between Japanese Black and Holstein cattle to detect nucleotide polymorphisms influencing fatty acid composition in milk and beef. Five single nucleotide polymorphisms (SNPs) were identified in the CDS region, 28 SNPs in the PIA region and three SNPs in the PIII region. Association study revealed that CCT/CCT type of PIII_#1, #2/PIA_#26 indicated a higher percentage of C14:0 in the milk of the Holstein cattle than CCT/GTC type (p = 0.050) and that a difference of the percentage of C16:0 was observed between CCT/CCT and GTC/GTC type (p = 0.023). CDS_#2 T/T type indicated a higher percentage of C18:0 than T/C type (p = 0.008). In addition, the Japanese Black cattle with CC/GT type of PIII_#1, #2 showed a higher percentage of C18:2 in the meat than those with GT/GT type (p = 0.025). Since PIII is the promoter specific to mammary gland during lactation, the altered expression of the ACACA gene owing to the SNPs in the PIII region may influence the fatty acid composition in the milk. PMID:22718502

  4. Total lipid and fatty acid composition of eight strains of marine diatoms

    NASA Astrophysics Data System (ADS)

    Liang, Ying; Mai, Kang-Sen; Sun, Shi-Chun

    2000-12-01

    Fatty acid composition and total lipid content of 8 strains of marine diatoms ( Nitzschia frustrula, Nitzschia closterium, Nitzschia incerta, Navicula pelliculosa, Phaeodactylum tricornutum, Synedra fragilaroides) were examined. The microalgae were grown under defined conditions and harvested at the late exponential phase. The major fatty acids in most strains were 14?0 (1.0% 6.3%), 16?0 (13.5 26.4%), 16?1n-7 (21.1% 46.3%) and 20?5n-3 (6.5% 19.5%). The polyunsaturated fatty acids 16?2n-4, 16?3n-4, 16?4n-1 and 20?4n-6 also comprised a significant proportion of the total fatty acids in some strains. The characteristic fatty acid composition of diatoms is readily distinguishable from those of other microalgal groups. Significant concentration of the polyunsaturated fatty acid 20?5n-3 (eicosapentaenoic acid) was present in each strain, with the highest proportion in B222 (19.5%).

  5. Mapping quantitative trait loci (QTLs) for fatty acid composition in an interspecific cross of oil palm

    PubMed Central

    Singh, Rajinder; Tan, Soon G; Panandam, Jothi M; Rahman, Rahimah Abdul; Ooi, Leslie CL; Low, Eng-Ti L; Sharma, Mukesh; Jansen, Johannes; Cheah, Suan-Choo

    2009-01-01

    Background Marker Assisted Selection (MAS) is well suited to a perennial crop like oil palm, in which the economic products are not produced until several years after planting. The use of DNA markers for selection in such crops can greatly reduce the number of breeding cycles needed. With the use of DNA markers, informed decisions can be made at the nursery stage, regarding which individuals should be retained as breeding stock, which are satisfactory for agricultural production, and which should be culled. The trait associated with oil quality, measured in terms of its fatty acid composition, is an important agronomic trait that can eventually be tracked using molecular markers. This will speed up the production of new and improved oil palm planting materials. Results A map was constructed using AFLP, RFLP and SSR markers for an interspecific cross involving a Colombian Elaeis oleifera (UP1026) and a Nigerian E. guinneensis (T128). A framework map was generated for the male parent, T128, using Joinmap ver. 4.0. In the paternal (E. guineensis) map, 252 markers (199 AFLP, 38 RFLP and 15 SSR) could be ordered in 21 linkage groups (1815 cM). Interval mapping and multiple-QTL model (MQM) mapping (also known as composite interval mapping, CIM) were used to detect quantitative trait loci (QTLs) controlling oil quality (measured in terms of iodine value and fatty acid composition). At a 5% genome-wide significance threshold level, QTLs associated with iodine value (IV), myristic acid (C14:0), palmitic acid (C16:0), palmitoleic acid (C16:1), stearic acid (C18:0), oleic acid (C18:1) and linoleic acid (C18:2) content were detected. One genomic region on Group 1 appears to be influencing IV, C14:0, C16:0, C18:0 and C18:1 content. Significant QTL for C14:0, C16:1, C18:0 and C18:1 content was detected around the same locus on Group 15, thus revealing another major locus influencing fatty acid composition in oil palm. Additional QTL for C18:0 was detected on Group 3. A minor QTL for C18:2 was detected on Group 2. Conclusion This study describes the first successful detection of QTLs for fatty acid composition in oil palm. These QTLs constitute useful tools for application in breeding programmes. PMID:19706196

  6. Influence of oxidation on fulvic acids composition and biodegradability.

    PubMed

    Kozyatnyk, Ivan; ?wietlik, Joanna; Raczyk-Stanis?awiak, Ursula; D?browska, Agata; Klymenko, Nataliya; Nawrocki, Jacek

    2013-08-01

    Oxidation is well-known process of transforming natural organic matter during the treatment of drinking water. Chlorine, ozone, and chlorine dioxide are common oxidants used in water treatment technologies for this purpose. We studied the influence of different doses of these oxidants on by-products formation and changes in biodegradable dissolved organic carbon (BDOC) and molecular weight distribution (MWD) of fulvic acids (FA) with different BDOC content. Chlorination did not significantly change the MWD of FA and disinfection by-products formation. However, higher molecular weight compounds, than those in the initial FA, were formed. It could be a result of chlorine substitution into the FA structure. Chlorine dioxide oxidized FA stronger than chlorine. During ozonation of FA, we found the highest increase of BDOD due to the formation of a high amount of organic acids and aldehydes. FA molecules were transformed into a more biodegradable form. Ozonation is the most preferable process among those observed for pre-treatment of FA before biofiltration. PMID:23746389

  7. The influence of feeding linoleic, gamma-linolenic and docosahexaenoic acid rich oils on rat brain tumor fatty acids composition and fatty acid binding protein 7 mRNA expression

    Microsoft Academic Search

    Javad Nasrollahzadeh; Fereydoun Siassi; Mahmood Doosti; Mohammad Reza Eshraghian; Fazel Shokri; Mohammad Hossein Modarressi; Javad Mohammadi-Asl; Khosro Abdi; Arash Nikmanesh; Seyed Morteza Karimian

    2008-01-01

    BACKGROUND: Experimental studies indicate that gamma linolenic acid (GLA) and docosahexaenoic acid (DHA) may inhibit glioma cells growth but effects of oral consumption of these fatty acids on brain tumor fatty acid composition have not been determined in vivo. METHODS: GLA oil (GLAO; 72% GLA), DHA oil (DHAO; 73% DHA) were fed to adult wistar rats (1 mL\\/rat\\/day) starting one

  8. COMPOSITION EN ACIDES AMINS DU LAIT DE TRUIE P.-H. DUE J. JUNG

    E-print Network

    Paris-Sud XI, Université de

    Josas RÉSUMÉ La composition en acides aminés des protéines du colostrum et du lait de 12 truies Lavge'azote, respectivement pour le colostrum et le lait, sont les suivantes : Par rapport au lait, le colostrum est plus lait : d'une part, au début de la lactation (qui correspond à la production de colostrum dont on sait

  9. Water deficit effects on caraway ( Carum carvi L.) growth, essential oil and fatty acid composition

    Microsoft Academic Search

    Bochra Laribi; Iness Bettaieb; Karima Kouki; Ali Sahli; Abdelaziz Mougou; Brahim Marzouk

    2009-01-01

    The Mediterranean region suffers of drought which affects plant behaviour regarding biochemical responses. Accordingly, the effects of water deficit on growth, essential oil and fatty acid composition of caraway (Carum carvi L.) seeds were investigated. Plants were treated with different levels of water deficit: control, moderate water deficit and severe water deficit. Plant growth (height, fresh and dry matter weight)

  10. EVALUATION OF POLY(LACTIC ACID) AND AGRICULTURAL COPRODUCTS AS GREEN COMPOSITE MATERIALS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Green composite materials of poly(lactic acid)(PLA) and agricultural coproducts such as sugar beet pulp(SBP), cuphea, lesquerella, and milkweed were compounded using a twin-screw extruder, molded by injection molding and evaluated for structural and mechanical properties using acoustic emission and ...

  11. Fatty Acid Composition of Subcutaneous Adipose Tissue from Male Calves at Different Stages of Growth1

    Microsoft Academic Search

    N. O. Huerta-Leidenz; H. R. Cross; J. W. Savell; D. K. Lunt; J. F. Baker; S. B. Smith

    The objective of this investigation was to compare fatty acid composition of calves from Bos taurus and Bos indicus cows across different stages of growth. Hereford ( H ) and Brahman ( B ) embryos were transferred to H or B cows (n = 58) to produce purebred Brahman (BB), purebred Hereford (HH), Hereford × Brahman (HB), and Brahman ×

  12. Prediction of Biodiesel Properties from Fatty Acid Composition using Linear Regression and ANN Techniques

    Microsoft Academic Search

    Madhu Agarwal; Kailash Singh; S. P. Chaurasia

    2010-01-01

    Biodiesel is currently the most widely accepted alternative fuel for diesel engines due to its various advantages. The fatty acid composition of vegetable oils affects the fuel properties of biodiesel, such as viscosity, flash point, fire point, cloud point, pour point, iodine value and saponification value. In the present work, biodiesel was prepared from different vegetable oils and its physical

  13. Preparation of poly(lactic acid) and pectin composite films intended for application in antimicrobial packaging

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Composite films of pectin and poly(lactic acid) (PLA) were compounded by extrusion. A model antimicrobial polypeptide, nisin, was loaded into the film by diffusion. The incorporation of pectin into PLA resulted in a heterogeneous biphasic structure as revealed by scanning electronic microscopy, co...

  14. Different Oilseed Supplements Alter Fatty Acid Composition of Different Adipose Tissues of Adult Ewes.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lamb and mutton are important dietary components in human diets in northwest China and throughout the world. Fatty acid composition is an important factor in the definition of meat quality due to its association with meat odor and flavor and nutritional value of fat for human consumption. Twenty-f...

  15. Ontogenetic change in the lipid and fatty acid composition of scleractinian coral larvae

    E-print Network

    Cohen, Michael F.

    REPORT Ontogenetic change in the lipid and fatty acid composition of scleractinian coral larvae J-Verlag 2012 Abstract Some scleractinian coral larvae have an extraordinary capacity to delay metamorphosis, and this is reflected in the large geographic range of many species. Coral eggs typically contain a high proportion

  16. Antimicrobial activity of nisin incorporated in pectin and polylactic acid composite films against Listeria monocytogenes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Extruded composite films from 20% pectin and 80% polylactic acids (PLA) were developed and nisin was loaded into films by a diffusion post extrusion. Inhibitory activities of the films against Listeria monocytogenes were evaluated in brain heart infusion (BHI) broth, liquid egg white and orange juic...

  17. Fatty acid composition of human milk in atopic Danish mothers1-3

    Microsoft Academic Search

    Lotte Lauritzen; Liselotte Brydensholt Halkjær; Tina B Mikkelsen; Sjurdur F Olsen; Kim F Michaelsen; Lotte Loland; Hans Bisgaard

    Background: Atopic dermatitis has been related to a disturbed metabolism of polyunsaturated fatty acids (PUFAs). Objective: We tested whether the PUFA composition of breast milk differs significantly between mothers with atopic dermatitis, moth- ers with other types of atopy, and nonatopic mothers. We also in- vestigated whether differences in diet can explain possible observed differences. Design: Mothers with current or

  18. Photoperiod affects daily torpor and tissue fatty acid composition in deer mice

    NASA Astrophysics Data System (ADS)

    Geiser, Fritz; McAllan, B. M.; Kenagy, G. J.; Hiebert, Sara M.

    2007-04-01

    Photoperiod and dietary lipids both influence thermal physiology and the pattern of torpor of heterothermic mammals. The aim of the present study was to test the hypothesis that photoperiod-induced physiological changes are linked to differences in tissue fatty acid composition of deer mice, Peromyscus maniculatus (˜18-g body mass). Deer mice were acclimated for >8 weeks to one of three photoperiods (LD, light/dark): LD 8:16 (short photoperiod), LD 12:12 (equinox photoperiod), and LD 16:8 (long photoperiod). Deer mice under short and equinox photoperiods showed a greater occurrence of torpor than those under long photoperiods (71, 70, and 14%, respectively). The duration of torpor bouts was longest in deer mice under short photoperiod (9.3 ± 2.6 h), intermediate under equinox photoperiod (5.1 ± 0.3 h), and shortest under long photoperiod (3.7 ± 0.6 h). Physiological differences in torpor use were associated with significant alterations of fatty acid composition in ˜50% of the major fatty acids from leg muscle total lipids, whereas white adipose tissue fatty acid composition showed fewer changes. Our results provide the first evidence that physiological changes due to photoperiod exposure do result in changes in lipid composition in the muscle tissue of deer mice and suggest that these may play a role in survival of low body temperature and metabolic rate during torpor, thus, enhancing favourable energy balance over the course of the winter.

  19. Composition en acides amins des aliments et des rsidus de fermentation in vitro

    E-print Network

    Paris-Sud XI, Université de

    Composition en acides aminés des aliments et des résidus de fermentation in vitro M. ANTONGIOVANNI in vitro fermentation with rumen inoculum, and of the faeces relative to an in vivo digestibility trial run fermentation in vitro comme l'ont fait Dennison et Philips (1983) et des fèces. Pour des raisons de place, nous

  20. Effects of hydroxyapatite dosage on mechanical and biological behaviors of polylactic acid composite materials

    Microsoft Academic Search

    Po-Liang Lin; Hsu-Wei Fang; Tiffany Tseng; Wun-Hsing Lee

    2007-01-01

    Due to the widespread use of bioresorbable polylactic acid (PLA) based materials in biomedical applications, there is an increasing need to obtain independent control of key properties such as mechanical strength, degradation rate and bioactivity in order to further enhance the performance of the PLA based medical implants. Because PLA composites containing hydroxyapatite (HAp) particles can augment cell growth and

  1. Changes in the fatty acid composition of goat milk fat after a 48-hour fast

    E-print Network

    Paris-Sud XI, Université de

    Changes in the fatty acid composition of goat milk fat after a 48-hour fast Anne-Marie MASSART, B-9000 Ghent, Belgium. Summary. Five lactating goats were milked twice daily. After a control period of 3 days, they were fasted for 48 hr. The milk was collected at each milking. At the end

  2. Effects on milk yield and composition of infusions of volatile fatty acids and caseinate into

    E-print Network

    Paris-Sud XI, Université de

    Effects on milk yield and composition of infusions of volatile fatty acids and caseinate Laitière, Saint-Gilles, 35590 L'Hermitage, France Changes in milk secretion and composi- tion, particularly concentrate and 7.5% soya bean meal. Duodenal infusion of casein increased milk yield (+ 1.9 kg

  3. FATTY ACID COMPOSITION OF THE ESTUARINE AMPHIPOD, MELITA PLUMULOSA (ZEIDLER): LINK BETWEEN DIET AND FECUNDITY

    Microsoft Academic Search

    Ross V. Hyne; Francisco Sánchez-Bayo; Ashley D. Bryan; Emma L. Johnston; Reinier M. Mann

    2009-01-01

    The influence of various diets on the survival, fecundity, and the polyunsaturated fatty acid (PUFA) composition of the benthic estuarine amphipod Melita plumulosa (Zeidler) in laboratory cultures were determined. Apart from a natural silty sediment, six commercial food supplements were examined: an omega-6 PUFA enriched Spirulina-based dry powder, Sera micron; a shrimp- based pellet food; an omega-3 PUFA enriched algal

  4. The amino acid composition of the Sutter's Mill CM2 carbonaceous chondrite

    NASA Astrophysics Data System (ADS)

    Burton, Aaron S.; Glavin, Daniel P.; Elsila, Jamie E.; Dworkin, Jason P.; Jenniskens, Peter; Yin, Qing-Zhu

    2014-11-01

    We determined the abundances and enantiomeric compositions of amino acids in Sutter's Mill fragment #2 (designated SM2) recovered prior to heavy rains that fell April 25-26, 2012, and two other meteorite fragments, SM12 and SM51, that were recovered postrain. We also determined the abundance, enantiomeric, and isotopic compositions of amino acids in soil from the recovery site of fragment SM51. The three meteorite stones experienced terrestrial amino acid contamination, as evidenced by the low D/L ratios of several proteinogenic amino acids. The D/L ratios were higher in SM2 than in SM12 and SM51, consistent with rain introducing additional L-amino acid contaminants to SM12 and SM51. Higher percentages of glycine, ?-alanine, and ?-amino-n-butyric acid were observed in free form in SM2 and SM51 compared with the soil, suggesting that these free amino acids may be indigenous. Trace levels of D+L-?-aminoisobutyric acid (?-AIB) observed in all three meteorites are not easily explained as terrestrial contamination, as ?-AIB is rare on Earth and was not detected in the soil. Bulk carbon and nitrogen and isotopic ratios of the SM samples and the soil also indicate terrestrial contamination, as does compound-specific isotopic analysis of the amino acids in the soil. The amino acid abundances in SM2, the most pristine SM meteorite analyzed here, are approximately 20-fold lower than in the Murchison CM2 carbonaceous chondrite. This may be due to thermal metamorphism in the Sutter's Mill parent body at temperatures greater than observed for other aqueously altered CM2 meteorites.

  5. Influence de l'axnie sur la composition en acides amins des fces chez le rat et l'agneau

    E-print Network

    Paris-Sud XI, Université de

    Influence de l'axénie sur la composition en acides aminés des fèces chez le rat et l. Fecal amino acid composition in germfree and conventional rats and lambs. Apparent dry matter, nitrogen rats. Faecal dry matter, nitro- gen and AA excretions were lower in gf than in cv environment for lambs

  6. Chronic risperidone treatment preferentially increases rat erythrocyte and prefrontal cortex omega-3 fatty acid composition: Evidence for augmented biosynthesis

    Microsoft Academic Search

    Robert K. McNamara; Jessica A. Able; Ronald Jandacek; Therese Rider; Patrick Tso

    2009-01-01

    Prior clinical studies suggest that chronic treatment with atypical antipsychotic medications increase erythrocyte and postmortem prefrontal cortex (PFC) omega-3 fatty acid composition in patients with schizophrenia (SZ). However, because human tissue phospholipid omega-3 fatty acid composition is potentially influenced by multiple extraneous variables, definitive evaluation of this putative mechanism of action requires an animal model. In the present study, we

  7. Comparative studies on fatty acid composition of the ovaries and hepatopancreas at different physiological stages of the Chinese mitten crab

    Microsoft Academic Search

    Xue-Ping Ying; Wan-Xi Yang; Yong-Pu Zhang

    2006-01-01

    The fatty acid composition of the ovary at different physiological stages (immature, mature, spawning, egg loss and abortion) of the Chinese mitten crab Eriocheir sinensis was investigated with capillary gas chromatograph. A total of 18 types of fatty acids were found in the ovary of E. sinensis. Three of them were major fatty acids: oleic acid (C18:1) (31.96–37.31%), palmitic acid

  8. Nonprotein amino acid composition of flatpea ( Lathyrus sylvestris L.) as affected by ethephon seed treatments and seedling fertilization

    Microsoft Academic Search

    David M. Orcutt; Joyce G. Foster

    1990-01-01

    Use of flatpea (Lathyrus sylvestris L.) as a forage is limited because of nonuniform seed germination and the potentially toxic effects of 2,4-diaminobutyric\\u000a acid (A2bu), a nonprotein amino acid found in seeds and vegetative tissues. The effects of ethephon (2-chloroethyl phosphonic acid)\\u000a on seed germination, amino acid leachates of seeds, and amino acid composition (particularly A2bu) of seedlings were investigated.

  9. Fatty acid composition and desaturase gene expression in flax (Linum usitatissimum L.).

    PubMed

    Thambugala, Dinushika; Cloutier, Sylvie

    2014-11-01

    Little is known about the relationship between expression levels of fatty acid desaturase genes during seed development and fatty acid (FA) composition in flax. In the present study, we looked at promoter structural variations of six FA desaturase genes and their relative expression throughout seed development. Computational analysis of the nucleotide sequences of the sad1, sad2, fad2a, fad2b, fad3a and fad3b promoters showed several basic transcriptional elements including CAAT and TATA boxes, and several putative target-binding sites for transcription factors, which have been reported to be involved in the regulation of lipid metabolism. Using semi-quantitative reverse transcriptase PCR, the expression patterns throughout seed development of the six FA desaturase genes were measured in six flax genotypes that differed for FA composition but that carried the same desaturase isoforms. FA composition data were determined by phenotyping the field grown genotypes over four years in two environments. All six genes displayed a bell-shaped pattern of expression peaking at 20 or 24 days after anthesis. Sad2 was the most highly expressed. The expression of all six desaturase genes did not differ significantly between genotypes (P?=?0.1400), hence there were no correlations between FA desaturase gene expression and variations in FA composition in relatively low, intermediate and high linolenic acid genotypes expressing identical isoforms for all six desaturases. These results provide further clues towards understanding the genetic factors responsible for FA composition in flax. PMID:24871199

  10. Multifaceted chitin/poly(lactic-co-glycolic) acid composite nanogels.

    PubMed

    Rejinold, N Sanoj; Biswas, Raja; Chellan, Gopi; Jayakumar, R

    2014-06-01

    Cyto-compatible, 80nm sized chitin/PLGA composite nanogels (chit/PLGA-comp NGs) were prepared by regeneration method and characterized. The multifaceted chit/PLGA-comp NGs were surface modified with Au, Fe3O4, CdTe/ZnTe-QDs and umbelliferone, respectively. 185nm sized Au-chit/PLGA-comp NGs, 170nm sized QD-chit/PLGA-comp-NGs and 160nm sized Fe3O4-chit/PLGA-comp-NGs showed RF heating. The QD-chit/PLGA-comp-NGs and 180nm sized umb-chit/PLGA-comp-NGs were well uptaken by Escherichia coli, Staphylococcus aureus and Candida albicans. The chit/PLGA-comp NGs could be useful for microbial monitoring and RF application for cancer therapy. The preliminary data showed that multifaceted chit/PLGA-comp-NGs could be useful for hyperthermia for cancer treatment and microbial labelling and imaging. PMID:24685461

  11. Polymorphisms in lipogenic genes and milk fatty acid composition in Holstein dairy cattle.

    PubMed

    Nafikov, Rafael A; Schoonmaker, Jon P; Korn, Kathleen T; Noack, Kristin; Garrick, Dorian J; Koehler, Kenneth J; Minick-Bormann, Jennifer; Reecy, James M; Spurlock, Diane E; Beitz, Donald C

    2014-12-01

    Changing bovine milk fatty acid (FA) composition through selection can decrease saturated FA (SFA) consumption, improve human health and provide a means for manipulating processing properties of milk. Our study determined associations between milk FA composition and genes from triacylglycerol (TAG) biosynthesis pathway. The GC dinucleotide allele of diacylglycerol O-acyltransferase 1:g.10433-10434AA >GC was associated with lower palmitic acid (16:0) concentration but higher oleic (18:1 cis-9), linoleic (18:2 cis-9, cis-12) acid concentrations, and elongation index. Accordingly, the GC dinucleotide allele was associated with lower milk fat percentage and SFA concentrations but higher monounsaturated FA and polyunsaturated FA (PUFA) concentrations. The glycerol-3-phosphate acyltransferase, mitochondrial haplotypes were associated with higher myristoleic acid (14:1 cis-9) concentration and C14 desaturation index. The 1-acylglycerol-3-phosphate acyltransferase 1 haplotypes were associated with higher PUFA and linoleic acid concentrations. The results of this study provide information for developing genetic tools to modify milk FA composition in dairy cattle. PMID:25304740

  12. During the first trial, we examined the postprandial amino acid composition of the contents collected during 12 consecutive hours. The samples collected during 3 hours were pooled together.

    E-print Network

    Paris-Sud XI, Université de

    During the first trial, we examined the postprandial amino acid composition of the contents were then hydrolyzed by 6 N hydrochloric acid for the amino acid determination. Variations in the amino acid compositions during the day are low, especially as regards the extraction residues. The amino acid

  13. Egg fatty acid composition from lake trout fed two Lake Michigan prey fish species.

    PubMed

    Honeyfield, Dale C; Fitzsimons, John D; Tillitt, Donald E; Brown, Scott B

    2009-12-01

    We previously demonstrated that there were significant differences in the egg thiamine content in lake trout Salvelinus namaycush fed two Lake Michigan prey fish (alewife Alosa pseudoharengus and bloater Coregonus hoyi). Lake trout fed alewives produced eggs low in thiamine, but it was unknown whether the consumption of alewives affected other nutritionally important components. In this study we investigated the fatty acid composition of lake trout eggs when females were fed diets that resulted in different egg thiamine concentrations. For 2 years, adult lake trout were fed diets consisting of four combinations of captured alewives and bloaters (100% alewives; 65% alewives, 35% bloaters; 35% alewives, 65% bloaters; and 100% bloaters). The alewife fatty acid profile had higher concentrations of arachidonic acid and total omega-6 fatty acids than the bloater profile. The concentrations of four fatty acids (cis-13, 16-docosadienoic, eicosapentaenoic, docosapentaenoic, and docosahexaenoic acids) were higher in bloaters than in alewives. Although six fatty acid components were higher in lake trout eggs in 2001 than in 2000 and eight fatty acids were lower, diet had no effect on any fatty acid concentration measured in lake trout eggs in this study. Based on these results, it appears that egg fatty acid concentrations differ between years but that the egg fatty acid profile does not reflect the alewife-bloater mix in the diet of adults. The essential fatty acid content of lake trout eggs from females fed alewives and bloaters appears to be physiologically regulated and adequate to meet the requirements of developing embryos. PMID:20218501

  14. Self-assembly of amphiphilic dendritic dipeptides into helical pores

    NASA Astrophysics Data System (ADS)

    Percec, Virgil; Dulcey, Andrés E.; Balagurusamy, Venkatachalapathy S. K.; Miura, Yoshiko; Smidrkal, Jan; Peterca, Mihai; Nummelin, Sami; Edlund, Ulrica; Hudson, Steven D.; Heiney, Paul A.; Duan, Hu; Magonov, Sergei N.; Vinogradov, Sergei A.

    2004-08-01

    Natural pore-forming proteins act as viral helical coats and transmembrane channels, exhibit antibacterial activity and are used in synthetic systems, such as for reversible encapsulation or stochastic sensing. These diverse functions are intimately linked to protein structure. The close link between protein structure and protein function makes the design of synthetic mimics a formidable challenge, given that structure formation needs to be carefully controlled on all hierarchy levels, in solution and in the bulk. In fact, with few exceptions, synthetic pore structures capable of assembling into periodically ordered assemblies that are stable in solution and in the solid state have not yet been realized. In the case of dendrimers, covalent and non-covalent coating and assembly of a range of different structures has only yielded closed columns. Here we describe a library of amphiphilic dendritic dipeptides that self-assemble in solution and in bulk through a complex recognition process into helical pores. We find that the molecular recognition and self-assembly process is sufficiently robust to tolerate a range of modifications to the amphiphile structure, while preliminary proton transport measurements establish that the pores are functional. We expect that this class of self-assembling dendrimers will allow the design of a variety of biologically inspired systems with functional properties arising from their porous structure.

  15. Effects of ileal resection on biliary lipids and bile acid composition in patients with Crohn's disease.

    PubMed Central

    Lapidus, A; Einarsson, K

    1991-01-01

    Biliary lipid composition, cholesterol saturation, and bile acid pattern were determined in fasting duodenal bile of 10 patients (four men and six women, mean age 41 years) with Crohn's disease and a history of ileal resection (mean 64 cm). The data were compared with corresponding values in a group of healthy subjects. None of the patients with Crohn's disease had supersaturated bile. Cholesterol saturation was significantly lower in the patients with Crohn's disease than in the healthy subjects. The molar percentage of cholesterol was also lower among the patients but there was no significant difference. The molar percentages of phospholipids and bile acids were normal. Bile acid composition in the patients with ileal resection was characterised by a significant decrease in the deoxycholic acid fraction and a pronounced increase in the ursodeoxycholic acid fraction compared with the healthy subjects. The surprisingly high percentage of ursodeoxycholic acid may contribute to the low degree of cholesterol saturation in bile. Based on these results patients with Crohn's disease should not have an increased risk of cholesterol gall stone formation. PMID:1773954

  16. Fatty acid composition of Juniperus species (Juniperus section) native to Turkey.

    PubMed

    Güvenç, Aysegül; Küçükboyaci, Nurgün; Gören, Ahmet Ceyhan

    2012-07-01

    Fatty acid compositions of seeds of five taxa of the Juniperus section of the genus Juniperus L. (Cupressaceae), i. e. J. drupacea Lab., J. communis L. var. communis, J. communis var. saxatilis Pall., J. oxycedrus L. subsp. oxycedrus, and J. oxycedrus subsp. macrocarpa (Sibth. & Sm.) Ball, were investigated. Methyl ester derivatized fatty acids of the lipophylic extracts of the five species were comparatively analyzed by capillary gas chromatography-mass spectrometry (GC-MS). Juniperus taxa showed uniform fatty acid patterns, among which linoleic (25.8 - 32.5%), pinolenic (11.9 - 24.1%) and oleic acids (12.4 - 17.2%) were determined to be the main fractions in the seed oils. Juniperonic acid was found to be remarkably high in J. communis var. saxatilis (11.4%), J. oxycedrus subsp. oxycedrus (10.4%), and J. communis var. communis (10.1%). To the best of our knowledge, the present work discloses the first report on the fatty acid compositions of seeds of this Juniperus section grown in Turkey. PMID:22908582

  17. Preparation of capric acid\\/halloysite nanotube composite as form-stable phase change material for thermal energy storage

    Microsoft Academic Search

    Dandan Mei; Bing Zhang; Ruichao Liu; Yatao Zhang; Jindun Liu

    2011-01-01

    A novel form-stable composite as phase change material (PCM) for thermal energy storage was prepared by absorbing capric acid (CA) into halloysite nanotube (HNT). The composite PCM was characterized by TEM, FT-IR and DSC analysis techniques. The composite can contain capric acid as high as 60wt% and maintain its original shape perfectly without any CA leakage after subjected to 50

  18. Molecular Cloning of a Gene Encoding a Seed-Specific Protein with Nutritionally Balanced Amino Acid Composition from Amaranthus

    Microsoft Academic Search

    Anjana Raina; Asis Datta

    1992-01-01

    An albumin with a well-balanced amino acid composition and high levels of the essential amino acids was purified to homogeneity from the mature seeds of Amaranthus hypochondriacus. The amino acid composition of this protein is comparable to the World Health Organization recommended values for a highly nutritional protein. The protein is a 35-kDa monomer with four isoforms that can be

  19. Using Grey Model GM(2,1) and Pseudo Amino Acid Composition to Predict Protein Subcellular Location

    Microsoft Academic Search

    Wei-Zhong Lin; Xuan Xiao

    2008-01-01

    Identifying the subcellular localization of proteins is particularly helpful in the functional annotation of gene products. Based on the concept of pseudo amino acid composition, a novel representation of protein sequence, grey pseudo amino acid (grey-PseAA) was introduced. The advantage by incorporating the grey-PseAA into the pseudo amino acid composition is that it can catch the essence of the overall

  20. Breast cancer risk and erythrocyte compositions of n-3 highly unsaturated fatty acids in Japanese.

    PubMed

    Kuriki, Kiyonori; Hirose, Kaoru; Wakai, Kenji; Matsuo, Keitaro; Ito, Hidemi; Suzuki, Takeshi; Hiraki, Akio; Saito, Toshiko; Iwata, Hiroji; Tatematsu, Masae; Tajima, Kazuo

    2007-07-15

    Dietary intake of fish rich in n-3 highly unsaturated fatty acids (HUFAs), such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), has been proposed to decrease cancer risk. In contrast to results from laboratory studies, however, protective effects for breast cancer have proved equivocal in epidemiological studies. In the present case-control study, we examined associations between breast cancer risk and fatty acid compositions in erythrocyte membranes as biomarkers for those intakes. Dietary information and blood samples were collected from 103 incident breast cancer cases and 309 non-cancer controls (matched by age and season) and erythrocyte fatty acids were measured using accelerated solvent extraction and gas-liquid chromatography. Dietary intake of n-3 HUFAs demonstrated a negative association with risk (the highest to the lowest tertile, odds ratio (OR), 0.51; 95% confidence interval (CI), 0.27-0.98; p(trend)<0.05), but there was no association with those of saturated fatty acids (SFAs) and meat. Moreover, risk was inversely associated with erythrocyte compositions of EPA (OR, 0.27; 95% CI, 0.14-0.53; p(trend)<0.0001), DHA (OR, 0.06; 95% CI, 0.02-0.16; p(trend)<0.0001) and n-3 HUFAs (OR, 0.11; 95% CI, 0.05-0.24; p(trend)<0.0001), and positively with that of SFAs (OR, 12.29; 95% CI, 4.94-30.57; p(trend)<0.0001) and the ratio of SFAs/n-3 HUFAs (OR, 14.65; 95% CI, 5.67-37.82; p(trend)<0.0001). In conclusion, we showed that erythrocyte compositions of specific fatty acids derived from fish intake, as biomarkers, are associated with lower risk of breast cancer, but further studies are needed to investigate mechanisms linked to the etiology. PMID:17354239

  1. Compositional and Temperature Effects of Phosphoric Acid Fractionation on ?47 Analysis and Implications for Discrepant Calibrations

    NASA Astrophysics Data System (ADS)

    Defliese, W.; Hren, M. T.; Lohmann, K. C.

    2014-12-01

    An essential procedure to increase the analytical efficiency of ?47 measurements requires raising the temperature of phosphoric acid digestion for carbonate materials. This temperature change introduces a fractionation offset in ?47 that must be accounted for prior to calculation of temperatures of carbonate formation and to allow interlaboratory comparison of results. We measured the phosphoric acid fractionation factor relative to reaction at 25 °C for calcite, aragonite, and dolomite across a temperature range from 25-90 °C. Significantly, all three minerals behave similarly during phosphoric acid digestion, allowing for a single temperature dependent acid fractionation relationship: 1000ln?𝐶𝑂2(𝐴𝑐𝑖𝑑)?𝛥47=(0.022434±0.001490)?10^6 𝑇2 ?(0.2524±0.0168) where ? is the phosphoric acid fractionation factor, and T is in degrees Kelvin. Mineralogical or isotopic compositional effects on the fractionation factor were not observed, suggesting that this acid fractionation factor may be valid for all carbonate minerals. We also present inorganic temperature calibrations for both calcite and aragonite at low temperatures (5-70 °C) and find them to agree with prior published data. Using the new acid fractionation factor, published ?47-temperature calibrations are recalculated. This analysis confirms a statistically significant ?47-temperature calibration difference between data analyzed at 25 °C versus higher temperatures. The origin of the discrepancy remains unknown, but it appears that the acid fractionation factor is not the cause.

  2. A mathematical relationship between the fatty acid composition of the diet and that of the adipose tissue in man

    Microsoft Academic Search

    A. C. Beynen; R. J. J. Hermus; J. G. A. J. Hautvast

    1980-01-01

    Based on literature data, the hypothesis is advanced that in human subjects a direct mathematical relationship exists between the average fatty acid composition of the habitual diet and that of the lipid stores of subcutaneous adipose tissue. Since the half-life of adipose tissue fatty acids in man is in the order of 600 days, the fatty acid pattern of depot

  3. Correlation of erythrocyte fatty acid composition and dietary intakes with markers of atherosclerosis in patients with myocardial infarction

    Microsoft Academic Search

    Yongsoon Park; Jeehyun Lim; Yongju Kwon; Jaeung Lee

    2009-01-01

    The purpose of this study was to examine the hypothesis that erythrocytes that are low in n-3 fatty acids and high in trans-fatty acids and nutrient intakes are associated with the risk of atherosclerosis. Fifty patients with acute nonfatal myocardial infarction were recruited to measure their dietary intake, erythrocyte fatty acid composition, intima medial thickness (IMT), and the Gensini score,

  4. Fouling of reverse osmosis and nanofiltration membranes by humic acid—Effects of solution composition and hydrodynamic conditions

    Microsoft Academic Search

    Chuyang Y. Tang; Young-Nam Kwon; James O. Leckie

    2007-01-01

    Fouling of reverse osmosis (RO) and nanofiltration (NF) membranes by humic acid, a recalcitrant natural organic matter (NOM), was systematically investigated. The membrane flux performance depended on both hydrodynamic conditions (flux and cross-flow velocity) and solution composition (humic acid concentration, pH, ionic strength, and calcium concentration), and was largely independent of virgin membrane properties. While increasing humic acid concentration and

  5. Survey of safflower (Carthamus tinctorius L.) germplasm for variants in fatty acid composition and other seed characters

    Microsoft Academic Search

    J. Fernández-Martinez; M. Rio; A. Haro

    1993-01-01

    Two hundred safflower accessions, originated in 37 countries, and multiplied in two environments, were evaluated for fatty acid composition of the seed oil and other seed characters. Overall mean values of stearic and palmitic acids were similar in both environments but differed for seed weight and oil content. Oleic and linoleic acids showed also similar overall mean content in both

  6. Fatty acid composition of habitual omnivore and vegetarian diets.

    PubMed

    Mann, Neil; Pirotta, Yvonne; O'Connell, Stella; Li, Duo; Kelly, Fiona; Sinclair, Andy

    2006-07-01

    High-fat diets are implicated in the onset of cardiovascular disease (CVD), cancer, and obesity. Large intakes of saturated and trans FA, together with low levels of PUFA, particularly long-chain (LC) omega-3 (n-3) PUFA, appear to have the greatest impact on the development of CVD. A high n-6:n-3 PUFA ratio is also considered a marker of elevated risk of CVD, though little accurate data on dietary intake is available. A new Australian food composition database that reports FA in foods to two decimal places was used to assess intakes of FA in four habitual dietary groups. Analysis using the database found correlations between the dietary intakes of LC n-3 PUFA and the plasma phospholipid LC n-3 PUFA concentrations of omnivore and vegetarian subjects. High meat-eaters (HME), who consumed large amounts of food generally, had significantly higher LC n-3 PUFA intakes (0.29 g/d) than moderate meat-eaters (MME) (0.14 g/d), whose intakes in turn were significantly higher than those of ovolacto-vegetarians or vegans (both 0.01 g/d). The saturated FA intake of MME subjects (typical of adult male Australians) was not different from ovolacto-vegetarian intakes, whereas n-6:n-3 intake ratios in vegetarians were significantly higher than in omnivores. Thus, accurate dietary and plasma FA analyses suggest that regular moderate consumption of meat and fish maintains a plasma FA profile possibly more conducive to good health. PMID:17069347

  7. GC constituents and relative codon expressed amino acid composition in cyanobacterial phycobiliproteins.

    PubMed

    Kannaujiya, Vinod K; Rastogi, Rajesh P; Sinha, Rajeshwar P

    2014-08-10

    The genomic as well as structural relationship of phycobiliproteins (PBPs) in different cyanobacterial species are determined by nucleotides as well as amino acid composition. The genomic GC constituents influence the amino acid variability and codon usage of particular subunit of PBPs. We have analyzed 11 cyanobacterial species to explore the variation of amino acids and causal relationship between GC constituents and codon usage. The study at the first, second and third levels of GC content showed relatively more amino acid variability on the levels of G3+C3 position in comparison to the first and second positions. The amino acid encoded GC rich level including G rich and C rich or both correlate the codon variability and amino acid availability. The fluctuation in amino acids such as Arg, Ala, His, Asp, Gly, Leu and Glu in ? and ? subunits was observed at G1C1 position; however, fluctuation in other amino acids such as Ser, Thr, Cys and Trp was observed at G2C2 position. The coding selection pressure of amino acids such as Ala, Thr, Tyr, Asp, Gly, Ile, Leu, Asn, and Ser in ? and ? subunits of PBPs was more elaborated at G3C3 position. In this study, we observed that each subunit of PBPs is codon specific for particular amino acid. These results suggest that genomic constraint linked with GC constituents selects the codon for particular amino acids and furthermore, the codon level study may be a novel approach to explore many problems associated with genomics and proteomics of cyanobacteria. PMID:24933001

  8. The degree of dietary fatty acid unsaturation affects torpor patterns and lipid composition of a hibernator.

    PubMed

    Geiser, F; McAllan, B M; Kenagy, G J

    1994-01-01

    Diets rich in unsaturated and polyunsaturated fatty acids have a positive effect on mammalian torpor, whereas diets rich in saturated fatty acids have a negative effect. To determine whether the number of double bonds in dietary fatty acids are responsible for these alterations in torpor patterns, we investigated the effect of adding to the normal diet 5% pure fatty acids of identical chain length (C18) but a different number of double bonds (0, 1, or 2) on the pattern of hibernation of the yellow-pine chipmunk, Eutamias amoenus. The response of torpor bouts to a lowering of air temperature and the mean duration of torpor bouts at an air temperature of 0.5 degree C (stearic acid C18:0, 4.5 +/- 0.8 days, oleic acid C18:1, 8.6 +/- 0.5 days; linoleic acid C18:2, 8.5 +/- 0.7 days) differed among animals that were maintained on the three experimental diets. The mean minimum body temperatures (C18:0, +2.3 +/- 0.3 degrees C; C18:1, +0.3 +/- 0.2 degree C; C18:2, -0.2 +/- 0.2 degrees C), which torpid individuals defended by an increase in metabolic rate, and the metabolic rate of torpid animals also differed among diet groups. Moreover, diet-induced differences were observed in the composition of total lipid fatty acids from depot fat and the phospholipid fatty acids of cardiac mitochondria. For depot fat 7 of 13 and for heart mitochondria 7 of 14 of the identified fatty acids differed significantly among the three diet groups. Significant differences among diet groups were also observed for the sum of saturated, unsaturated and polyunsaturated fatty acids.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7962785

  9. Relationship between cannabinoids content and composition of fatty acids in hempseed oils.

    PubMed

    Petrovi?, Marinko; Debeljak, Željko; Kezi?, Nataša; Džidara, Petra

    2015-03-01

    Hempseed oils acquired on the Croatian markets were characterised by cannabinoid content and fatty acid composition. The new method for determination of cannabinoid content was developed and validated in the range of 0.05-60 mg/kg, and the content of tetrahydrocannabinol varied between 3.23 and 69.5 mg/kg. Large differences among the samples were obtained for phenotype ratio suggesting that not all of analysed hempseed oils were produced from industrial hemp. Sample clustering based on cannabinoid content assigned samples to two groups closely related to the phenotype ratios obtained. The results of this study confirm that hempseed oil is a good source of polyunsaturated fatty acids, especially ?-linolenic and stearidonic acid, but the content varies a lot more than the omega-6/omega-3 ratio. The grouping of samples on fatty acid content assigned samples to two groups which were consistent with the groups obtained based on cannabinoid content clustering. PMID:25306338

  10. Alterations in lipid and fatty acid composition of the cyanobacterium Scytonema geitleri bharadwaja under water stress.

    PubMed

    Singh, M K; Rai, P K; Rai, A; Singh, S

    2014-01-01

    The composition of the glycerolipids [monogalactosyl diacylglycerol (MGDG), digalactosyl diacylglycerol (DGDG), sulfoquinovosyl diacylglycerol (SQDG) and phosphatidylglycerol (PG)] and alterations in their saturation and unsaturation levels in response to osmotic and matric water potential have been investigated in the cyanobacterium Scytonema geitleri Bharadwaja. The level of MGDG in S. geitleri was high followed by PG, DGDG and SQDG. Whereas, the amount of fatty acids namely palmitic, stearic, oleic, linoleic and linolenic acid were high, arachidic and behenic acid were, however, present in traces in the four glycerolipids. A significant reduction in the level of total lipid as well as individual class lipid was observed in S. geitleri in response to matric water potential to that of its total lipid and individual class lipid in response to osmotic water potential. The levels of polyunsaturated and unsaturated fatty acids also increased in response to matric water potential to that of osmotic water potential. PMID:25535713

  11. Antiamnesic effect of acyl-prolyl-containing dipeptide (GVS-111) in compression-induced damage to frontal cortex.

    PubMed

    Romanova, G A; Mirzoev, T K; Barskov, I V; Victorov, I V; Gudasheva, T A; Ostrovskaya, R U

    2000-09-01

    Antiamnestic effect of acyl-prolyl-containing dipeptide GVS-111 was demonstrated in rats with bilateral compression-induced damage to the frontal cortex. Both intraperitoneal and oral administration of the dipeptide improved retrieval of passive avoidance responses in rats with compression-induced cerebral ischemia compared to untreated controls. PMID:11177261

  12. Protein location prediction using atomic composition and global features of the amino acid sequence

    SciTech Connect

    Cherian, Betsy Sheena, E-mail: betsy.skb@gmail.com [Centre for Bioinformatics, University of Kerala, Kariyavattom Campus, Thiruvananthapuram, Kerala (India); Nair, Achuthsankar S. [Centre for Bioinformatics, University of Kerala, Kariyavattom Campus, Thiruvananthapuram, Kerala (India)] [Centre for Bioinformatics, University of Kerala, Kariyavattom Campus, Thiruvananthapuram, Kerala (India)

    2010-01-22

    Subcellular location of protein is constructive information in determining its function, screening for drug candidates, vaccine design, annotation of gene products and in selecting relevant proteins for further studies. Computational prediction of subcellular localization deals with predicting the location of a protein from its amino acid sequence. For a computational localization prediction method to be more accurate, it should exploit all possible relevant biological features that contribute to the subcellular localization. In this work, we extracted the biological features from the full length protein sequence to incorporate more biological information. A new biological feature, distribution of atomic composition is effectively used with, multiple physiochemical properties, amino acid composition, three part amino acid composition, and sequence similarity for predicting the subcellular location of the protein. Support Vector Machines are designed for four modules and prediction is made by a weighted voting system. Our system makes prediction with an accuracy of 100, 82.47, 88.81 for self-consistency test, jackknife test and independent data test respectively. Our results provide evidence that the prediction based on the biological features derived from the full length amino acid sequence gives better accuracy than those derived from N-terminal alone. Considering the features as a distribution within the entire sequence will bring out underlying property distribution to a greater detail to enhance the prediction accuracy.

  13. Fatty acid composition of lipids in pot marigold (Calendula officinalis L.) seed genotypes

    PubMed Central

    2013-01-01

    Background Calendula officinalis L. (pot marigold) is an annual aromatic herb with yellow or golden-orange flowers, native to the Mediterranean climate areas. Their seeds contain significant amounts of oil (around 20%), of which about 60% is calendic acid. For these reasons, in Europe concentrated research efforts have been directed towards the development of pot marigold as an oilseed crop for industrial purposes. Results The oil content and fatty acid composition of major lipid fractions in seeds from eleven genotypes of pot marigold (Calendula officinalis L.) were determined. The lipid content of seeds varied between 13.6 and 21.7 g oil/100 g seeds. The calendic and linoleic acids were the two dominant fatty acids in total lipid (51.4 to 57.6% and 28.5 to 31.9%) and triacylglycerol (45.7 to 54.7% and 22.6 to 29.2%) fractions. Polar lipids were also characterised by higher unsaturation ratios (with the PUFAs content between 60.4 and 66.4%), while saturates (consisted mainly of palmitic and very long-chain saturated fatty acids) were found in higher amounts in sterol esters (ranging between 49.3 and 55.7% of total fatty acids). Conclusions All the pot marigold seed oils investigated contain high levels of calendic acid (more than 50% of total fatty acids), making them favorable for industrial use. The compositional differences between the genotypes should be considered when breeding and exploiting the pot marigold seeds for nutraceutical and pharmacological purposes. PMID:23327299

  14. SCMCRYS: Predicting Protein Crystallization Using an Ensemble Scoring Card Method with Estimating Propensity Scores of P-Collocated Amino Acid Pairs

    PubMed Central

    Charoenkwan, Phasit; Shoombuatong, Watshara; Lee, Hua-Chin; Chaijaruwanich, Jeerayut; Huang, Hui-Ling; Ho, Shinn-Ying

    2013-01-01

    Existing methods for predicting protein crystallization obtain high accuracy using various types of complemented features and complex ensemble classifiers, such as support vector machine (SVM) and Random Forest classifiers. It is desirable to develop a simple and easily interpretable prediction method with informative sequence features to provide insights into protein crystallization. This study proposes an ensemble method, SCMCRYS, to predict protein crystallization, for which each classifier is built by using a scoring card method (SCM) with estimating propensity scores of p-collocated amino acid (AA) pairs (p?=?0 for a dipeptide). The SCM classifier determines the crystallization of a sequence according to a weighted-sum score. The weights are the composition of the p-collocated AA pairs, and the propensity scores of these AA pairs are estimated using a statistic with optimization approach. SCMCRYS predicts the crystallization using a simple voting method from a number of SCM classifiers. The experimental results show that the single SCM classifier utilizing dipeptide composition with accuracy of 73.90% is comparable to the best previously-developed SVM-based classifier, SVM_POLY (74.6%), and our proposed SVM-based classifier utilizing the same dipeptide composition (77.55%). The SCMCRYS method with accuracy of 76.1% is comparable to the state-of-the-art ensemble methods PPCpred (76.8%) and RFCRYS (80.0%), which used the SVM and Random Forest classifiers, respectively. This study also investigates mutagenesis analysis based on SCM and the result reveals the hypothesis that the mutagenesis of surface residues Ala and Cys has large and small probabilities of enhancing protein crystallizability considering the estimated scores of crystallizability and solubility, melting point, molecular weight and conformational entropy of amino acids in a generalized condition. The propensity scores of amino acids and dipeptides for estimating the protein crystallizability can aid biologists in designing mutation of surface residues to enhance protein crystallizability. The source code of SCMCRYS is available at http://iclab.life.nctu.edu.tw/SCMCRYS/. PMID:24019868

  15. Formation of titanium phosphate composites during phosphoric acid decomposition of natural sphene

    NASA Astrophysics Data System (ADS)

    Maslova, Marina V.; Rusanova, Daniela; Naydenov, Valeri; Antzutkin, Oleg N.; Gerasimova, Lidia G.

    2008-12-01

    Decomposition of mineral sphene, CaTiOSiO 4, by H 3PO 4 is investigated in detail. During the dissolution process, simultaneous calcium leaching and formation of titanium phosphate (TiP) take place. The main product of decomposition is a solid titanium phosphate-silica composite. The XRD, solid-sate NMR, IR, TGA, SEM and BET data were used to identify and characterize the composite as a mixture of crystalline Ti(HPO 4) 2·H 2O and silica. When 80% phosphoric acid is used the decomposition degree is higher than 98% and calcium is completely transferred into the liquid phase. Formation of Ti(HPO 4) 2·H 2O proceeds via formation of meta-stable titanium phosphate phases, Ti(H 2PO 4)(PO 4)·2H 2O and Ti(H 2PO 4)(PO 4). The sorption affinities of TiP composites were examined in relation to caesium and strontium ions. A decrease of H 3PO 4 concentration leads to formation of composites with greater sorption properties. The maximum sorption capacity of TiP is observed when 60% H 3PO 4 is used in sphene decomposition. The work demonstrates a valuable option within the Ti(HPO 4) 2·H 2O-SiO 2 composite synthesis scheme, to use phosphoric acid flows for isolation of CaHPO 4·2H 2O fertilizer.

  16. Lipid and fatty acid compositions of cod ( Gadus morhua), haddock ( Melanogrammus aeglefinus) and halibut ( Hippoglossus hippoglossus)

    NASA Astrophysics Data System (ADS)

    Zeng, Duan; Mai, Kangsen; Ai, Qinghui; Milley, Joyce E.; Lall, Santosh P.

    2010-12-01

    This study was conducted to compare lipid and fatty acid composition of cod, haddock and halibut. Three groups of cod (276 g ± 61 g), haddock (538 g ± 83 g) and halibut (3704 g ± 221 g) were maintained with commercial feeds mainly based on fish meal and marine fish oil for 12 weeks prior to sampling. The fatty acid compositions of muscle and liver were determined by GC/FID after derivatization of extracted lipids into fatty acid methyl esters (FAME). Lipids were also fractionated into neutral and polar lipids using Waters silica Sep-Pak?. The phospholipid fraction was further separated by high-performance thin-layer chromatography (HPTLC) and the FAME profile was obtained. Results of the present study showed that cod and haddock were lean fish and their total muscle lipid contents were 0.8% and 0.7%, respectively, with phospholipid constituting 83.6% and 87.5% of the total muscle lipid, respectively. Halibut was a medium-fat fish and its muscle lipid content was 8%, with 84% of the total muscle lipid being neutral lipid. Total liver lipid contents of cod, haddock and halibut were 36.9%, 67.2% and 30.7%, respectively, of which the neutral lipids accounted for the major fraction (88.1%-97.1%). Polyunsaturated fatty acids were the most abundant in cod and haddock muscle neutral lipid. Monounsaturated fatty acid level was the highest in halibut muscle neutral lipid. Fatty acid compositions of phospholipid were relatively constant. In summary, the liver of cod and haddock as lean fish was the main lipid reserve organ, and structural phospholipid is the major lipid form in flesh. However, as a medium-fat fish, halibut stored lipid in both their liver and muscle.

  17. Fatty acid composition of plasma lipids and erythrocyte membranes during simulated extravehicular activity

    NASA Astrophysics Data System (ADS)

    Skedina, M. A.; Katuntsev, V. P.; Buravkova, L. B.; Naidina, V. P.

    Ten subjects (from 27 to 41 years) have been participated in 32 experiments. They were decompressed from ground level to 40-35 kPa in altitude chamber when breathed 100% oxygen by mask and performed repeated cycles of exercises (3.0 Kcal/min). The intervals between decompressions were 3-5 days. Plasma lipid and erythrocyte membrane fatty acid composition was evaluated in the fasting venous blood before and immediately after hypobaric exposure. There were 7 cases decompression sickness (DCS). Venous gas bubbles (GB) were detected in 27 cases (84.4%). Any significant changes in the fatty acid composition of erythrocyte membranes and plasma didn't practically induce after the first decompression. However, by the beginning of the second decompression the total lipid level in erythrocyte membranes decreased from 54.6 mg% to 40.4 mg% in group with DCS symptoms and from 51.2 mg% to 35.2 mg% (p < 0.05) without DCS symptoms. In group with DCS symptoms a tendency to increased level of saturated fatty acids in erythrocyte membranes (16:0, 18:0), the level of the polyunsaturated linoleic fatty acid (18:2) and arachidonic acid (20:4) tended to be decreased by the beginning of the second decompression. Insignificant changes in blood plasma fatty acid composition was observed in both groups. The obtained biochemical data that indicated the simulated extravehicular activity (EVA) condition is accompanied by the certain changes in the blood lipid metabolism, structural and functional state of erythrocyte membranes, which are reversible. The most pronounced changes are found in subjects with DCS symptoms.

  18. Dietary fat in relation to erythrocyte fatty acid composition in men.

    PubMed

    Takkunen, Markus; Agren, Jyrki; Kuusisto, Johanna; Laakso, Markku; Uusitupa, Matti; Schwab, Ursula

    2013-11-01

    Erythrocyte membrane fatty acid (EMFA) composition is used in the validation of food frequency questionnaires (FFQ) and the evaluation of dietary fat quality. In this cross-sectional study we aimed to investigate associations of diet with EMFA. Altogether, 1,033 randomly selected Finnish men, aged from 47 to 75 years filled in a FFQ and their EMFA composition was analyzed. Marine polyunsaturated fatty acid (PUFA) intake correlated positively with erythrocyte eicosapentaenoic and docosahexaenoic acids (r(s) = 0.415 and r(s) = 0.340, respectively, P < 0.001) and inversely with all n-6 PUFA analyzed (P < 0.001). PUFA intake from spreads and cooking fats correlated positively with alpha-linolenic (ALA), linoleic (LNA) and nervonic acids (r(s) = 0.229, r(s) = 0.160 and r(s) = 0.143, respectively, P < 0.001). Milk fat intake was associated with myristic and behenic acids (r(s) = 0.186 and r(s) = 0.132, respectively P < 0.001). Butter users had lower ALA and LNA proportions (mol%) than non-users (0.16 ± 0.04 vs. 0.19 ± 0.05, P < 0.001 and 7.77 ± 1.02 vs. 8.12 ± 1.11, P = 0.001). Higher PUFA intake from meat was related to decreased long-chain n-3 (P < 0.001) and increased n-6 PUFA (P < 0.001) proportions. In conclusion, EMFA composition reflects particularly well the intakes of n-3 PUFA, whereas other associations remained lower. Yet, all main sources of dietary fat were related with EMFA. The dietary effect on the nervonic acid proportion was confirmed. PMID:23975575

  19. Oxidative damage of aromatic dipeptides by the environmental oxidants NO2? and O3.

    PubMed

    Gamon, L F; White, J M; Wille, U

    2014-11-01

    Irreversible oxidative damage at both aromatic side chains and dipeptide linkage occurs in the aromatic N- and C-protected dipeptides 7-11 upon exposure to the environmental pollutants NO2? and O3. The reaction proceeds through initial oxidation of the aromatic ring by in situ generated NO3?, or by NO2?, respectively, which leads to formation of nitroaromatic products. The indole ring in Phe-Trp undergoes oxidative cyclization to a pyrroloindoline. An important reaction pathway for dipeptides with less oxidisable aromatic side chains proceeds through fragmentation of the peptide bond with concomitant acyl migration. This process is likely initiated by an ionic reaction of the amide nitrogen with the NO2? dimer, N2O4. PMID:25207524

  20. Physicochemical analysis of Psophocarpus tetragonolobus (L.) DC seeds with fatty acids and total lipids compositions.

    PubMed

    Mohanty, Chandra Sekhar; Pradhan, Rama Chandra; Singh, Vinayak; Singh, Neha; Pattanayak, Rojalin; Prakash, Om; Chanotiya, Chandan Singh; Rout, Prasant Kumar

    2015-06-01

    Psophocarpus tetragonolobus (L.) DC. is a tropical legume with potential nutritional properties. In present study, the physical properties and proximate composition of the seeds were evaluated. Besides, the physico-chemical properties of fatty oil from fully mature seeds were also studied. The fatty oil compositions of immature, mature and fully mature seeds were evaluated by GC-FID, GC/MS and (1)H-NMR. The study revealed that, fatty oil from fully mature seeds contained high proportion of unsaturated fatty acids (75.5 %), whereas immature seeds contained higher percentage of saturated fatty acid (61.3 %). In addition, unsaponification matter (0.25 %) of fatty oil was identified as stigmasterol (66.4 %) and ?-sitosterol (25.1 %). Total lipids of fully mature seeds were extracted and isolated as neutral, glyco- and phospholipids. Overall, the fatty oil of fully mature seeds was enriched with mono-unsaturated fatty acids (38.6 %) and poly-unsaturated fatty acids (36.9 %) without trans-fatty acids, thus meeting the edible oil standard. PMID:26028749

  1. The Fatty Acid Composition of Phosphatidylglycerol and Sulfoquinovosyldiacylglycerol of Higher Plants in Relation to Chilling Sensitivity

    PubMed Central

    Kenrick, Janette R.; Bishop, David G.

    1986-01-01

    The fatty acid composition of phosphatidylglycerol and sulfoquinovosyldiacylglycerol has been measured in the leaves of 27 species of higher plants from six families whose members differed in their degrees of chilling sensitivity. The content of high melting point fatty acids (represented by the sum of hexadecanoic, trans-3-hexadecenoic and octadecanoic acids) in phosphatidylglycerols varied little between members of the same plant family and was not obviously related to the relative chilling sensitivity of members of that family. The saturated fatty acid content (hexadecanoic + octadecanoic acids) of sulfoquinovosyldiacylglycerols also appeared to be characteristic of a plant family, although some exceptions were found. In one case, (Carica papaya) the content of saturated fatty acids in sulfoquinovosyldiacylglycerol was sufficiently high to suggest that this lipid could undergo phase separations above 0°C. It is concluded that the content of high melting point fatty acids in leaf phosphatidylglycerol is not a direct indication of the chilling sensitivity of a plant, but rather may be a reflection of the genetic origin of that plant. PMID:16664962

  2. Phospholipid Analyses for Microbial Community Composition in Alpine Acid Rock Drainage

    NASA Astrophysics Data System (ADS)

    Webster, C. E.; Tapp, J. B.; Pfiffner, S. M.

    2008-12-01

    This project is examining factors of non-anthropogenic acid rock drainage that influence microbial community composition in the Peekaboo Gulch drainage basin (Sawatch Range, Colorado). At this site, natural acid rock drainage outflows from acidic springs (pH=2.6) on Red Mountain. The acid drainage converges with South Fork Lake Creek (pH ~ 7.0, prior to convergence) two miles down gradient. Sediment samples were collected across confluences with gradient of pH, temperature, conductivity and metal concentration. In-situ parameter measurements ranged from 2.3 to 7.9 of pH, 3.8 to 16.6 degree Celsius for temperature, and 34.9 to 1820 for conductivity. Biomass as measured by phospholipids ranged from 280 to 95,900 pmol/g sediment. The only relationship between the in situ parameters and the phospholipid profiles is a weak positive correlation between pH and branched monounsaturated fatty acid methyl esters in that at a pH greater than 5.0 these fatty acid methyl esters were detected. The phospholipid profiles were diverse across the samples. These profiles changed with respect to the spatial relationship within the drainage pattern. The highest alpine samples contained greater relative abundances of monounsaturated fatty acid methyl esters compared to the lower alpine samples. Microbial community profiles shifted at each confluence depending on water source chemistry. Continuing research is needed to determine other biogeochemical factors that may influence these community shifts.

  3. Effect of growth phase on the fatty acid compositions of four species of marine diatoms

    NASA Astrophysics Data System (ADS)

    Liang, Ying; Mai, Kangsen

    2005-04-01

    The fatty acid compositions of four species of marine diatoms ( Chaetoceros gracilis MACC/B13, Cylindrotheca fusiformis MACC/B211, Phaeodactylum tricornutum MACC/B221 and Nitzschia closterium MACC/B222), cultivated at 22°C±1°C with the salinity of 28 in f/2 medium and harvested in the exponential growth phase, the early stationary phase and the late stationary phase, were determined. The results showed that growth phase has significant effect on most fatty acid contents in the four species of marine diatoms. The proportions of 16:0 and 16:1n-7 fatty acids increased while those of 16:3n-4 and eicosapentaenoic acid (EPA) decreased with increasing culture age in all species studied. The subtotal of saturated fatty acids (SFA) increased with the increasing culture age in all species with the exception of B13. The subtotal of monounsaturated fatty acids (MUFA) increased while that of polyunsaturated fatty acids (PUFA) decreased with culture age in the four species of marine diatoms. MUFA reached their lowest value in the exponential growth phase, whereas PUFA reached their highest value in the same phase.

  4. Abnormalities in the fatty-acid composition of the serum phospholipids of stroke patients.

    PubMed Central

    Glew, Robert H.; Okolie, Henry; Huang, Yung-Sheng; Chuang, Lu-Te; Suberu, Ojo; Crossey, Michael; VanderJagt, Dorothy J.

    2004-01-01

    The incidence of cardiovascular diseases, stroke, and myocardial infarction is increasing in sub-Saharan Africa. Since dietary polyunsaturated fatty acids (PUFA) are protective of the cardiovascular system in humans, we were interested in the question of the PUFA status of adults in northern Nigeria who had experienced a recent stroke. We collected blood from 21 consecutive admissions for stroke (15 male patients, mean age 39.3 years and six females, mean age 40.7 years) to the Federal Medical Centre in Gombe, Nigeria and analyzed the fatty-acid composition of the serum phospholipids. Blood was collected from 30 healthy controls for comparison. The contribution palmitic acid made to the fatty-acid total was greatly decreased in the phospholipids of the stroke patients (29.2% versus 37.2 %, p < 0.001). However, the phospholipids of the stroke patients had significantly higher percentages of 20-, 22-, and 24-carbon saturated fatty acids, as well as higher proportions of the omega-6 fatty-acid, arachidonic acid (11.4 versus 8.14%, p < 0.001), and the omega-3 fatty-acid, docosahexaenoic acid (3.21 versus 1.80%, p < 0.001). Using the percentages and melting points of the individual fatty acids, we estimated that the acyl chains of the serum phospholipids of the stroke patients had a lower mean melting point than the controls (27.8 versus 34.6 degrees C, p < 0.001). Assuming that serum phospholipids are surrogates for tissue phospholipids, we conclude that the tissue membranes of the stroke patients may be considerably more fluid than those of the controls. PMID:15233494

  5. The effect of dietary docosahexaenoic acid on plasma lipoproteins and tissue fatty acid composition in humans

    Microsoft Academic Search

    G. J. Nelson; P. C. Schmidt; G. L. Bartolini; D. S. Kelley; David Kyle

    1997-01-01

    Normal, healthy male volunteers (n=6) were fed diets [high docosahexaenoic acid-DHA] containing 6 g\\/d of DHA for 90 d. The stabilization (low-DHA) diet contained\\u000a less than 50 mg\\/d of DHA. A control group (n=4) remained on the low-DHA diet for the duration of the study (120 d). Blood samples were drawn on study days 30 (end of\\u000a the stabilization period),

  6. Benzimidazole as corrosion inhibitor for heat treated 6061 Al- SiCp composite in acetic acid

    NASA Astrophysics Data System (ADS)

    Chacko, Melby; Nayak, Jagannath

    2015-06-01

    6061 Al-SiCpcomposite was solutionizedat 350 °C for 30 minutes and water quenched. It was then underaged at 140 °C (T6 treatment). The aging behaviour of the composite was studied using Rockwell B hardness measurement. Corrosion behaviour of the underaged sample was studied in different concentrations of acetic acid and at different temperatures. Benzimidazole at different concentrations was used for the inhibition studies. Inhibition efficiency of benzimidazole was calculated for different experimental conditions. Thermodynamic parameters were found out which suggested benzimidazole is an efficient inhibitor and it adsorbed on to the surface of composite by mixed adsorption where chemisorption is predominant.

  7. Recent developments in altering the fatty acid composition of ruminant-derived foods.

    PubMed

    Shingfield, K J; Bonnet, M; Scollan, N D

    2013-03-01

    There is increasing evidence to indicate that nutrition is an important factor involved in the onset and development of several chronic human diseases including cancer, cardiovascular disease (CVD), type II diabetes and obesity. Clinical studies implicate excessive consumption of medium-chain saturated fatty acids (SFA) and trans-fatty acids (TFA) as risk factors for CVD, and in the aetiology of other chronic conditions. Ruminant-derived foods are significant sources of medium-chain SFA and TFA in the human diet, but also provide high-quality protein, essential micronutrients and several bioactive lipids. Altering the fatty acid composition of ruminant-derived foods offers the opportunity to align the consumption of fatty acids in human populations with public health policies without the need for substantial changes in eating habits. Replacing conserved forages with fresh grass or dietary plant oil and oilseed supplements can be used to lower medium-chain and total SFA content and increase cis-9 18:1, total conjugated linoleic acid (CLA), n-3 and n-6 polyunsaturated fatty acids (PUFA) to a variable extent in ruminant milk. However, inclusion of fish oil or marine algae in the ruminant diet results in marginal enrichment of 20- or 22-carbon PUFA in milk. Studies in growing ruminants have confirmed that the same nutritional strategies improve the balance of n-6/n-3 PUFA, and increase CLA and long-chain n-3 PUFA in ruminant meat, but the potential to lower medium-chain and total SFA is limited. Attempts to alter meat and milk fatty acid composition through changes in the diet fed to ruminants are often accompanied by several-fold increases in TFA concentrations. In extreme cases, the distribution of trans 18:1 and 18:2 isomers in ruminant foods may resemble that of partially hydrogenated plant oils. Changes in milk fat or muscle lipid composition in response to diet are now known to be accompanied by tissue-specific alterations in the expression of one or more lipogenic genes. Breed influences both milk and muscle fat content, although recent studies have confirmed the occurrence of genetic variability in transcript abundance and activity of enzymes involved in lipid synthesis and identified polymorphisms for several key lipogenic genes in lactating and growing cattle. Although nutrition is the major factor influencing the fatty acid composition of ruminant-derived foods, further progress can be expected through the use of genomic or marker-assisted selection to increase the frequency of favourable genotypes and the formulation of diets to exploit this genetic potential. PMID:23031638

  8. Conjugated linoleic acid alters growth performance, tissue lipid deposition, and fatty acid composition of darkbarbel catfish (Pelteobagrus vachelli).

    PubMed

    Dong, Gui-Fang; Liu, Wen-Zuo; Wu, Lin-Zhou; Yu, Deng-Hang; Huang, Feng; Li, Peng-Cheng; Yang, Yan-Ou

    2015-02-01

    Fatty liver syndrome is a prevalent problem of farmed fish. Conjugated linoleic acid (CLA) has received increased attention recently as a fat-reducing fatty acid to control fat deposition in mammals. Therefore, the aim of the present study was to determine whether dietary CLA can reduce tissue lipid content of darkbarbel catfish (Pelteobagrus vachelli) and whether decreased lipid content is partially due to alterations in lipid metabolism enzyme activities and fatty acid profiles. A 76-day feeding trial was conducted to investigate the effect of dietary CLA on the growth, tissue lipid deposition, and fatty acid composition of darkbarbel catfish. Five diets containing 0 % (control), 0.5 % (CLA0.5), 1 % (CLA1), 2 % (CLA2), and 3 % (CLA3) CLA levels were evaluated. Results showed that fish fed with 2-3 % CLA diets showed a significantly lower specific growth rate and feed conversion efficiency than those fed with the control diet. Dietary CLA decreased the lipid contents in the liver and intraperitoneal fat with the CLA levels from 1 to 3 %. Fish fed with 2-3 % CLA diets showed significantly higher lipoprotein lipase and hepatic triacylglycerol lipase activities in liver than those of fish fed with the control, and fish fed with 1-3 % CLA diets had significantly higher pancreatic triacylglycerol lipase activities in liver than those of fish fed with the control. Dietary CLA was incorporated into liver, intraperitoneal fat, and muscle lipids, with higher percentages observed in liver compared with other tissues. Liver CLA deposition was at the expense of monounsaturated fatty acids (MUFA). In contrast, CLA deposition appeared to be primarily at the expense of MUFA and n-3 polyunsaturated fatty acids (PUFA) in the intraperitoneal fat, whereas in muscle it was at the expense of n-3 PUFA. Our results suggested that CLA at a 1 % dose can reduce liver lipid content without eliciting any negative effect on growth rate in darkbarbel catfish. This lipid-lowering effect could be in part due to an increment in the activity of lipid metabolism enzymes and an extensive interconversion of fatty acids. Although CLA deposition in muscle (0.66-3.19 % of total fatty acids) are higher than presented in natural sources of CLA, EPA (C20:5n-3) in fish muscle appears simultaneously expendable, when the fish fed with 2-3 % CLA. PMID:25362563

  9. Melt Rheological Behaviour and Thermal Properties of Low Density Polyethylene\\/Palm Kernel Shell Composites: Effect of Polyethylene Acrylic Acid

    Microsoft Academic Search

    H. Salmah; B. Y. Lim; P. L. Teh

    2012-01-01

    The melt flow behaviour and thermal properties of low density polyethylene (LDPE)\\/palm kernel shell (PKS) composites were studied. Polyethylene acrylic acid (PEAA) was used as compatibilizer in the composites. The results showed that the increasing of PKS loading had decreased MFI values of LDPE\\/PKS composites. The presence of PEAA increased the MFI values of the LDPE\\/PKS composites. The apparent viscosity

  10. Synthesis, characterization of novel silicotungstic acid incorporated SPEEK\\/PVA-co-ethylene-based composite membranes for fuel cell

    Microsoft Academic Search

    Baskar Ramaganthan; P. M. Sivakumar; Sangeetha Dharmalingam

    2011-01-01

    Sulfonated polyether ether ketone (SPEEK) is prepared by the sulfonation of polyether ether ketone (PEEK). Five of the composite\\u000a membranes (PSW1–PSW5) with various percentage compositions of the SPEEK, PVA-co-ethylene, and silicotungstic acid (SWA) were\\u000a prepared. The prepared composite membranes were characterized using Fourier transform infrared spectroscopy (FT-IR), X-ray\\u000a diffraction (XRD), and thermogravimetric analysis (TGA). Surface morphology of the composite membranes

  11. Effect of Conjugated Linoleic Acid or Oleic Acid Addition on Fatty Acid Composition Profiles of Poultry Meat 

    E-print Network

    Shin, Dae Keun

    2011-08-08

    and fish oil diet had a lower C20:4 (arachidonic acid, AA, n-6) deposition but showed a higher n-3/n-6 ratio in breast and thigh meat than those fed a flaxseed oil diet and CLA and flaxseed oil diet (P < 0.05). The C20:4 and n-3/n-6 ratio of breast...

  12. Poly(L-lactic acid)/poly(glycolic acid) microfibrillar polymer-polymer composites: Preparation and viscoelastic properties

    NASA Astrophysics Data System (ADS)

    Kimble, L. D.; Fakirov, S.; Bhattacharyya, D.

    2015-05-01

    Microfibrillar composites (MFCs) from petrochemical-derived polymers have been investigated for several years and the technique can result in significant improvements in mechanical properties when compared with the neat matrix material of the respective composite. The current work applies the technique to biodegradable, biocompatible polymers for potential applications in bioabsorbable medical devices. MFCs were prepared from melt blended poly(L-lactic acid) (PLLA) and poly(glycolic acid) (PGA) via cold drawing then compression molding of extruded yarn. These MFCs were shown to have higher Young's moduli than that of neat PLLA but for load-bearing applications the creep characteristics are of interest. The MFC sheets resulting from compression molding were subjected to tensile relaxation tests at 37°C in the fiber orientation direction. Specimens were also tested via dynamic mechanical thermal analysis (DMTA). Neat PLLA specimens were subjected to the same tests for comparison. Results indicate that at 37°C PLLA/PGA MFCs exhibit lower creep resistance than that of neat PLLA due to the more rapid relaxation of stress observed. DMTA results elucidate the loss modulus changes in PLLA/PGA MFCs which occur as the material approaches the glass transition temperature of PGA (˜45°C).

  13. Fatty acid composition of four potential aquatic weeds and their possible use as fish-feed neutraceuticals

    Microsoft Academic Search

    A. K. Mukherjee; P. Kalita; B. G. Unni; S. B. Wann; D. Saikia; P. K. Mukhopadhyay

    2010-01-01

    A study was conducted to explore the fatty acid composition of four aquatic weeds, namely Salvinia cuculata, Trapa natans, Lemna minor and Ipomoea reptans collected from water bodies of Assam, India. It has been observed that C24:1 (Cis-15 Tetracosenoic acid) followed by C16:1 n-3 (9-Hexadecenoic acid) are the predominant fatty acids in these aquatic weeds and among them, Ipomoea reptans

  14. Effects on plasma lipids and fatty acid composition of very low fat diets enriched with fish or kangaroo meat

    Microsoft Academic Search

    Andrew J. Slnclalra; Kerin O'Deab; Graeme Dunstana; Paul D. Irelandb; Maggie Nlallb

    1987-01-01

    The effects of very low fat diets (<7% energy) enriched with different sources of long chain (C20 and C22) polyunsaturated\\u000a fatty acids (PUFA) on plasma lipid levels and plasma fatty acids (PUFA) on plasma lipid levels and plasma fatty acid composition\\u000a were studied in 13 healthy volunteers. Three diets provided 500 g\\/day of tropical Australian fish (rich in arachidonic acid

  15. Effects of Prilled Fatty Acids and Calcium Salts of Fatty Acids on Rumen Fermentation, Nutrient Digestibilities, Milk Production, and Milk Composition1

    Microsoft Academic Search

    D. J. Schauff; J. H. Clark

    1989-01-01

    Lactating Holstein cows averaging 193 d postpartum and fitted with rumen can- nulae were used in two experiments to investigate the effects of supplementing Ca salts of fatty acids or prilled fatty acids to the diet on fermentation in the rumen, apparent total tract nutrient di- gestibility, milk production, and milk composition. Cows were fed ad libitum total mixed diets

  16. Effect of type of suckling and polyunsaturated fatty acid use on lamb production. 2. Chemical and fatty acid composition of raw and cooked meat

    Microsoft Academic Search

    Arcangelo Vicenti; Maria Antonietta Colonna; Marco Ragni; Francesco Toteda

    2010-01-01

    This study was carried out in order to examine the chemical and fatty acid composition of raw and cooked meat obtained from lambs raised under mothers or reared by artificial suckling with acidified milk replacers with or without polyunsaturated fatty acid (PUFA) supplementation. Meat samples were taken from twenty Gentile di Puglia male lambs subjected to the following feeding treatments:

  17. Structures and conformation of a benzo-12-crown-4 containing dipeptide.

    PubMed

    Tripathi, Garima; Ramanathan, Gurunath

    2015-05-01

    Crystal structures of the dipeptide Boc-12-Crown-4-l-DOPA-Gly-OMe (chi) and Boc-12-Crown-4-d/l-DOPA-Gly-OMe (rac) were solved by single crystal X-ray diffraction. Analysis of the packing differences in the crystal reveals that the presence of a water molecule in chi enables intermolecular contacts with the solvent that result in a different conformation of the dipeptide backbone itself. An uncommon N?H…N interaction stabilizes the peptide in its solid state. © 2015 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 104: 148-155, 2015. PMID:25645572

  18. Sterol regulatory element binding transcription factor 1 (SREBF1) polymorphism and milk fatty acid composition.

    PubMed

    Nafikov, R A; Schoonmaker, J P; Korn, K T; Noack, K; Garrick, D J; Koehler, K J; Minick-Bormann, J; Reecy, J M; Spurlock, D E; Beitz, D C

    2013-04-01

    Milk is known to contain high concentrations of saturated fatty acids-such as palmitic (16:0), myristic (14:0), and lauric (12:0) acids-that can raise plasma cholesterol in humans, making their presence in milk undesirable. The main objective of our candidate gene study was to develop genetic markers that can be used to improve the healthfulness of bovine milk. The sterol regulatory element binding transcription factor 1 (SREBF1) known to regulate the transcription of lipogenic genes together with SREBF chaperone and insulin induced gene 1 were the candidate genes. The results showed significant association of the overall SREBF1 haplotypes with milk production and variations in lauric (12:0) and myristic (14:0) acid concentrations in milk. Haplotype H1 of SREBF1 was the most desirable to improve milk healthfulness because it was significantly associated with lower lauric (12:0) and myristic (14:0) acid concentrations compared with haplotype H3 of SREBF1, and lower lauric acid (12:0) concentration compared with haplotype H2 of SREBF1. Haplotype H1 of SREBF1, however, was significantly associated with lower milk production compared with haplotype H3 of SREBF1. We did not detect any significant associations between genetic polymorphisms in insulin induced gene 1 (INSIG1) and SREBF chaperone and milk fatty acid composition. In conclusion, genetic polymorphisms in SREBF1 can be used to develop genetic tools for the selection of animals producing milk with healthier fatty acid composition. PMID:23403193

  19. Dietary effects on lipid and fatty acid composition of Clistoronia magnifica (Trichoptera: Limnephilidae)

    SciTech Connect

    Hanson, B.J.; Cummins, K.W.; Cargill, A.S. II; Lowry, R.R.

    1983-02-01

    Dietary influences on growth and biochemical composition of the caddisfly Clistoronia magnifica were examined with a variety of diets including wheat, microbially conditioned alder, and wheat plus alder. Larvae receiving wheat were able to override direct temperature effects, while those on alder could not. Based on larval growth rates, and pupal weights and lipid contents, the authors concluded that alder alone was a poor quality food for late instar C. magnifica. A diet of alder plus wheat allowed the most growth, and produced the largest pupae, however pupae from larvae given just wheat had the largest lipid stores. Among-treatment differences in protein and lipid content, and fatty acid composition verified the importance of fatty acids synthesized from dietary carbohydrate. It appears that a carbohydrate source for the metabolism of storage lipid is a major requirement for late instar C. magnifica.

  20. Detailed Dimethylacetal and Fatty Acid Composition of Rumen Content from Lambs Fed Lucerne or Concentrate Supplemented with Soybean Oil

    PubMed Central

    Alves, Susana P.; Santos-Silva, José; Cabrita, Ana R. J.; Fonseca, António J. M.; Bessa, Rui J. B.

    2013-01-01

    Lipid metabolism in the rumen is responsible for the complex fatty acid profile of rumen outflow compared with the dietary fatty acid composition, contributing to the lipid profile of ruminant products. A method for the detailed dimethylacetal and fatty acid analysis of rumen contents was developed and applied to rumen content collected from lambs fed lucerne or concentrate based diets supplemented with soybean oil. The methodological approach developed consisted on a basic/acid direct transesterification followed by thin-layer chromatography to isolate fatty acid methyl esters from dimethylacetal, oxo- fatty acid and fatty acid dimethylesters. The dimethylacetal composition was quite similar to the fatty acid composition, presenting even-, odd- and branched-chain structures. Total and individual odd- and branched-chain dimethylacetals were mostly affected by basal diet. The presence of 18?1 dimethylacetals indicates that biohydrogenation intermediates might be incorporated in structural microbial lipids. Moreover, medium-chain fatty acid dimethylesters were identified for the first time in the rumen content despite their concentration being relatively low. The fatty acids containing 18 carbon-chain lengths comprise the majority of the fatty acids present in the rumen content, most of them being biohydrogenation intermediates of 18?2n?6 and 18?3n?3. Additionally, three oxo- fatty acids were identified in rumen samples, and 16-O-18?0 might be produced during biohydrogenation of the 18?3n?3. PMID:23484024

  1. Effects of aluminum on organic acid, sugar and amino acid composition of the root system of sorghum (Sorghum bicolor L. Moench)

    Microsoft Academic Search

    J. Cambraia; F. R. Galvani; M. M. Estevão; R. SantAnna

    1983-01-01

    The effects of aluminum on the accumulation of sugars, amino acids and organic acids in two hybrid cultivars of sorghum were studied.The concentration of these organic compounds increased in the roots of the Al?treated plants, mainly in the tolerant cultivar. The composition of the organic acid fraction showed a significantly higher accumulation of trans?aconitate and malate in the tolerant cultivar

  2. Factors determining the hatching success of Antarctic krill Euphausia superba embryo: lipid and fatty acid composition

    Microsoft Academic Search

    Toshihiro Yoshida; Patti Virtue; So Kawaguchi; Peter D. Nichols

    The present study addresses the effect of maternal diet on hatching success and condition of embryos and larvae of Antarctic\\u000a krill Euphausia superba. Lipid and fatty acid content and composition were determined in field and laboratory samples. Developmental stages analyzed\\u000a in embryos included: multiple-cell, gastrula, and limb-bud stages. Larval stages analyzed included: nauplius I, nauplius II,\\u000a and metanauplius. Laboratory-reared embryos

  3. Oil concentration and fatty acid composition of achenes of Helianthus species (Asteraceae) from Canada

    Microsoft Academic Search

    Gerald J. Seiler; Mary E. Brothers

    1999-01-01

    The cultivated sunflower (Helianthus annuus) is one of the four most important annual crops in the world grown for its edible oil. Species of the genusHelianthus served as the ancestral stock for the present cultivated sunflower. The wild relatives are a valuable genetic reservoir for\\u000a improving the crop species. This study examined oil concentration and fatty acid composition in oil

  4. Fatty acid composition of sunflower ( Helianthus annuus L.) oil as influenced by seed position

    Microsoft Academic Search

    D. C. Zimmerman; G. N. Fick

    1973-01-01

    The variation in fatty acid composition of the oil from seeds located in different positions within an individual sunflower\\u000a head was determined. Each head was divided into three ring-shaped zones and four samples were taken from each zone. Ten heads\\u000a from an inbred line and ten from an open-pollinated variety were sampled. Position of the seed within the head had

  5. Polyaniline–poly(2-acrylamido-2-methyl-1-propanosulfonic acid) composite thin films: structure and properties

    Microsoft Academic Search

    Liliana Hechavarr??a; Hailin Hu; Marina E. Rincón

    2003-01-01

    Polyaniline (PANI)–poly(2-acrylamido-2-methyl-1-propanosulfonic acid) (PAMPS) composite thin films are obtained by a chemical bath deposition method on conductive glass substrates. The incorporation of the polyacid in PANI, demonstrated by atomic force microscopy, ultraviolet–visible spectroscopy and Fourier transform infrared spectroscopy studies, causes changes in the electronic structure of PANI and gives a different microstructure when compared to the unmodified PANI film. The

  6. Solid particle erosion behaviour of glass fibre reinforced boric acid filled epoxy resin composites

    Microsoft Academic Search

    Mehmet Bagci; Huseyin Imrek

    2011-01-01

    The tests which involved angular aluminium (Al2O3) particles with two different sizes of approximately 200 and 400?m were conducted at the operating conditions namely different impact velocities of approximately 23, 34 and 53m\\/s, two different fibre directions [0° (0\\/90) and 45° (45\\/?45)] and three different impingement angles of 30°, 60° and 90°. New composites with addition of Boric Acid filler

  7. Phylogenetic Analysis and In Situ Identification of Bacteria Community Composition in an Acidic Sphagnum Peat Bog

    Microsoft Academic Search

    Svetlana N. Dedysh; Timofei A. Pankratov; Svetlana E. Belova; Irina S. Kulichevskaya; Werner Liesack

    2006-01-01

    The Bacteria community composition in an acidic Sphagnum peat bog (pH 3.9 to 4.5) was characterized by a combination of 16S rRNA gene clone library analysis, rRNA-targeted fluorescence in situ hybridization (FISH), and cultivation. Among 84 environmental 16S rRNA gene clones, a set of only 16 cloned sequences was closely related (>95% similarity) to taxonomically described organisms. Main groups of

  8. Fatty acid content and composition of english beef, lamb and pork at retail

    Microsoft Academic Search

    M. Enser; K. Hallett; B. Hewitt; G. A. J. Fursey; J. D. Wood

    1996-01-01

    We have determined the fatty acid content and composition of retail samples of meat and assessed them with respect to UK dietary recommendations. Fifty beef sirloin steaks, pork chops and lamb chops were purchased from four supermarkets on separate occasions. The percentage of muscle (boneless basis) in the samples was 84.4 ± 4.3, 69.8 ± 7.7 and 78.9 ± 7.1

  9. Preparation and conductivity of PVA films composited with decatungstomolybdovanadogermanic heteropoly acid

    Microsoft Academic Search

    Wenqi Feng; Jiaqing Wang; Qingyin Wu

    2005-01-01

    In this work, the polyvinyl alcohol (PVA) films composited with decatungstomolybdovanadogermanic heteropoly acid (HPA) were prepared. Infrared (IR) spectra revealed that the Keggin structure characteristic of the GeW10MoVO405? anion was present in PVA films. At room temperature (20°C), the conductivity of the samples of different HPA content increased from 3.16×10?3 to 1.22×10?2Scm?1. The results indicated that they are new kind

  10. Preparation and conductivity of polyvinyl alcohol (PVA) films composited with molybdotungstovanadogermanic heteropoly acid

    Microsoft Academic Search

    Yanli Cui; Jianwei Mao; Qingyin Wu

    2004-01-01

    In this work, the polyvinyl alcohol (PVA) films composited with molybdotungstovanadogermanic heteropoly acid were prepared. Infrared spectra (IR) revealed that the Keggin structure characteristic of the GeMo2W9VO405? anion was present in PVA films. At room temperature (20°C), the conductivity of the samples of different HPA content increased from 2.46×10?3 to 9.92×10?3Scm?1. The results indicated that they are new kind of

  11. Pervaporation of fluoroethanol\\/water and methacrylic acid\\/water mixtures through PVA composite membranes

    Microsoft Academic Search

    Sang-Man Ahn; Jong-Wook Ha; Jeong-Hoon Kim; Yong-Taek Lee; Soo-Bok Lee

    2005-01-01

    2,2,2-Trifluoroethyl methacrylate (TFEMA) is used in the preparation of functional water-repellent paints and optical fiber coating agents, and is manufactured by esterification of 2,2,2-trifluoroethanol (TFEA) and methacrylic acid (MA) via a dehydration process using azeotropic distillation. To substitute for the hazardous dehydration process, composite-type PVA pervaporation membranes were prepared using glutaraldehyde on a porous polyethersulfone support and their basic pervaporation

  12. Synthesis and characterization of composite membranes based on ?-zirconium phosphate and silicotungstic acid

    Microsoft Academic Search

    M. Helen; B. Viswanathan; S. Srinivasa Murthy

    2007-01-01

    The functional properties of the composite membrane generated from polyvinyl alcohol, zirconium phosphate and silicotungstic acid are described. The fabricated membranes were characterized by using FT-IR, XRD, TGA, DSC and SEM techniques. These fabricated membranes showed reduced methanol cross over (for possible application in DMFC) relative to that of Nafion® 115. A maximum proton conductivity of 10?2Scm?1 at 60% RH

  13. The effect of low temperatures on fatty acid composition of crops with different cold resistance

    Microsoft Academic Search

    S. P. Makarenko; L. V. Dudareva; A. I. Katyshev; T. A. Konenkina; A. V. Nazarova; E. G. Rudikovskaya; N. A. Sokolova; V. V. Chernikova; Yu. M. Konstantinov

    2011-01-01

    The study was focused on fatty acid (FA) composition of lipids from the seedlings and roots of crops having different cold\\u000a resistance and grown at 27°C or 4°C. Biosynthesis of FA in the lipids of seedlings and roots of cold-susceptible maize (Zea mays L.) at both growth temperatures was controlled by chloroplast ?6 desaturase and microsomal ?6 desaturase, respectively. The

  14. Fatty-acid composition of the colostrum and serum of fullterm and preterm delivering Iraqi mothers

    Microsoft Academic Search

    Y Y Al-Tamer; AA Mahmood

    2004-01-01

    Objective: To determine the lipid components of colostrum and the fatty-acid (FA) composition of the colostrum and serum of Iraqi mothers, whether their delivery be fullterm (FT) or preterm (PT).Design: A collection of colostrum and serum samples of FT and PT delivering Iraqi mothers.Setting: Mosul province (in the north of Iraq).Subjects: Colostrum and blood samples were obtained from FT and

  15. Fatty Acid Composition of Milk from Genetically Normotensive and Hypertensive Rats1

    Microsoft Academic Search

    DAVID E. MILLS; RON P. WARD; ANDYUNG SHENG HUANG

    To assess milk fatty acid composition in genetically normotensive (Wistar Kyoto, WKY) and spontaneously hypertensive (SH) rats, WKY and SH dams (n = ID\\/strain) were milked under halothane anesthesia on d 5, 13 and 21 postpartum. Milk sam ples of 0.5-1.0 mL were then analyzed by gas-liquid chromatography. Additional WKYand SH dams (n = 2\\/strain) were milked on d 5

  16. Short Communication: Effect of Stearoyl-Coenzyme A Desaturase Polymorphism on Fatty Acid Composition of Milk

    Microsoft Academic Search

    B. Moioli; G. Contarini; A. Avalli; G. Catillo; G. De Matteis; G. Masoero; F. Napolitano

    2007-01-01

    The effect of the stearoyl-CoA desaturase (SCD) gene on milk fatty acid composition was tested. Cows of 3 breeds of northern Italy, Piedmontese, Valdostana, and Jersey, were genotyped at exon 5 of the SCD gene. This has been suggested as a primary candidate gene to change the proportion of saturated vs. unsaturated fattyacidsinmilk,whereinasinglenucleotidepolymor- phism (C\\/T) gives rise to a different

  17. Amino acid composition and functional properties of giant red sea cucumber ( Parastichopus californicus ) collagen hydrolysates

    Microsoft Academic Search

    Zunying Liu; Yicheng Su; Mingyong Zeng

    2011-01-01

    Giant red sea cucumber (Parastichopus californicus) is an under-utilized species due to its high tendency to autolysis. The aim of this study was to evaluate the functional\\u000a properties of collagen hydrolysates from this species. The degree of hydrolysis (DH), amino acid composition, SDS-PAGE, emulsion\\u000a activity index (EAI), emulsion stability index (ESI), foam expansion (FE), and foam stability (FS) of hydrolysates

  18. Oil concentration and fatty acid composition of achenes of North American Helianthus (Asteraceae) species

    Microsoft Academic Search

    Gerald J. Seiler

    1994-01-01

    Oil concentration and fatty acid composition were determined in achenes of two annual Helianthus species (112 populations)\\u000a and 11 perennial species (103 populations) from the Great Lakes region and the Central Great Plains of the U.S. The highest\\u000a average oil concentration was observed in annualH. petiolaris Nutt. with 28.8%, followedbyH. annuus L. with 25.4%. Among the perennial species,H. hirsutus Raf.

  19. Preparation and mechanical properties of polylactic acid composites containing hydroxyapatite fibers

    Microsoft Academic Search

    Toshihiro Kasuga; Yoshio Ota; Masayuki Nogami; Yoshihiro Abe

    2000-01-01

    Ceramic-polymer composite biomaterials were prepared by hot-pressing a mixture consisting of poly-l-lactic acid (PLA) and hydroxyapatite fibers (HAF) with dimensions of 40–150?m length and 2–10?m diameter, which were converted from ?-Ca(PO3)2 fibers. After PLA dissolved with methylene chloride was mixed with the fibers, the mixture was dried completely and subsequently hot-pressed uniaxially under a pressure of 40MPa at 180°C, resulting

  20. Differential Effects of Permeating and Nonpermeating Solutes on the Fatty Acid Composition of Pseudomonas putida

    Microsoft Academic Search

    LARRY J. HALVERSON; MARY K. FIRESTONE

    2000-01-01

    We examined the effect of reduced water availability on the fatty acid composition of Pseudomonas putida strain mt-2 grown in a defined medium in which the water potential was lowered with the permeating solutes NaCl or polyethylene glycol (PEG) with a molecular weight of 200 (PEG 200) or the nonpermeating solute PEG 8000. Transmission electron microscopy showed that 21.0-MPa PEG

  1. Modification of the fatty acid composition of L1210 murine leukemia cells

    Microsoft Academic Search

    C. Patrick Burns; DIANA G. LUTTENEGGERo; Shiao-Ping L. Wei; Arthur A. Spector

    1977-01-01

    We have compared the effect of diets containing 16% sunflower seed oil (polyunsaturated fat-rich) or 16% coconut oil (saturated\\u000a fat-rich) fed for 3–7 weeks on the composition of L1210 murine leukemia cells which were transplanted into the peritoneal\\u000a cavity during the final week of feeding. The L1210 phospholipids of mice fed the sunflower oil diet contained 43% polyenoic\\u000a fatty acids

  2. The fatty acid composition of the seed fat from Swietenia macrophylla

    Microsoft Academic Search

    M. M. Chakrabarty; D. K. Chowdhuri

    1957-01-01

    Summary  A light yellow oil was isolated in 50% yield from the decorticated seeds ofSwietenia macrophylla kina grown in India. The unrefined oil had a slightly bitter taste and an iodine value of 109.7. Other properties are reported.\\u000a \\u000a By means of spectrophotometry, fractional crystallization, and methyl ester distillation, the oil was found to have the following\\u000a fatty acid composition (as %):

  3. Influence des acides linolique (18:2 n-6) et ?-linolnique (18:3 n-3) sur la composition, la permabilit

    E-print Network

    Paris-Sud XI, Université de

    Influence des acides linoléique (18:2 n-6) et ?-linolénique (18:3 n-3) sur la composition, la, France. Summary. Influence of lnoleic acid and a-linolenic acid on the composition, permeabi7ity) with different linoleic and linolenic contents. Diet (L·) con- tained large amounts of linoleic acid (53

  4. Morphology and fatty acid composition of erythrocytes from monkeys exposed to ozone for one year

    SciTech Connect

    Larkin, E.C.; Goheen, S.C.; Rao, G.A.

    1983-12-01

    Monkeys (Macaca radiata) were exposed to a low dose (0.64 ppm) of ozone (O/sub 3/) for 8 hr each day over a 1-year period. Control monkeys were exposed to filtered air. The morphology of the red blood cell (RBC) from these monkeys was analyzed by scanning electron microscopy. Red cells from control monkeys had normal morphology with 69% having biconcave shape (discocytes). In O/sub 3/-exposed animals, blood contained only 35% discocytes. Knizocytes, stomatocytes, and spherocytes each have defined shape which are different from discocytes. The number of knizocytes and stomatocytes in O/sub 3/-exposed monkeys was that of controls. In addition, significant levels of spherocytes were observed while they were absent in the blood of controls. The fatty acid composition of RBC from control and O/sub 3/-exposed monkeys was the same. These were similar to that of human RBC. However, earlier reports of monkey RBC fatty acid composition differ from our results. These are discussed. The authors conclude that low-dose O/sub 3/ exposure changes the morphology, but not the fatty acid composition, of erthrocytes in vivo. 29 references.

  5. Dietary sandalwood seed oil modifies fatty acid composition of mouse adipose tissue, brain, and liver.

    PubMed

    Liu, Y; Longmore, R B

    1997-09-01

    Sandalwood (Santalum spicatum) seed oil, which occurs to about 50% of the weight of the seed kernels, contains 30-35% of total fatty acids (FA) as ximenynic acid (XMYA). This study was designed to obtain basic information on changes in tissue FA composition and on the metabolic fate of XMYA in mice fed a sandalwood seed oil (SWSO)-enriched diet. Female mice were randomly divided into three groups, each receiving different semisynthetic diets containing 5.2% (w/w) fat (standard laboratory diet), 15% canola oil, or 15% SWSO for 8 wk. The effects of SWSO as a dietary fat on the FA composition of adipose tissue, brain, and liver lipids were determined by analyses of FA methyl ester derivatives of extracted total lipid. The FA compositions of the liver and adipose tissue were markedly altered by the dietary fats, and mice fed on a SWSO-enriched diet were found to contain XMYA but only in low concentration (0.3-3%) in these tissues; XMYA was not detected in brain. Oleic acid was suggested to be a principal XMYA biotransformation product. The results were interpreted to suggest that the metabolism of XMYA may involve both biohydrogenation and oxidation reactions. PMID:9307938

  6. Analysis of the stable carbon isotope composition of formic and acetic acids.

    PubMed

    Lee, Xinqing; Zhang, Like; Huang, Daikuan; An, Ning; Yang, Fang; Jiang, Wei; Fang, Bin

    2013-05-15

    Formic and acetic acids are ubiquitous in the environment and in many biological processes. Analysis of the stable carbon isotope composition (?(13)C) of formic and acetic acids is important to understanding their biogeochemical cycles. However, it has been faced with poor accuracy and high detection limits due to their low carbon number, high hydrophilicity, and semi-volatility. Here we developed an analytical technique by needle trap and gas chromatography-isotope ratio mass spectrometry (GC-IRMS). The organic acids in aqueous solution were extracted using a NeedlEx needle through purge-and-trap and were analyzed by GC-IRMS for ?(13)C. The procedures incur no isotope fractionation. Defined as the point at which the mean ?(13)C is statistically the same as the given value and the analytical error starts rising, the method's detection limits are 200 and 100 mg/L for formic and acetic acids, respectively, with an uncertainty of approximately 0.5‰ in direct extraction and analysis. They were lowered to 1 mg/L with precision of 0.9‰ after samples were subjected to preconcentration. The method was successfully applied to natural samples as diverse as precipitation, vinegars, ant plasma, and vehicle exhaust, which vary considerably in concentration and matrix of the organic acids. It is applicable to the organic acids in not only aqueous solution but also gaseous phase. PMID:23395975

  7. Fatty acid composition of heart cells exposed to thermally oxidized fats.

    PubMed

    Bird, R P; Alexander, J C

    1979-10-01

    Corn oil and olive oil were thermally oxidized, and the free fatty acids from the fresh fats, and from the distillable non-urea-adductable (DNUA) fractions of the thermally oxidized fats were prepared. These were added as emulsions to the medium of primary cultures of heart endothelial and muscle cells from neonatal rats. After exposure for 24 hr, the fatty acid composition of the triacylglycerol (TC) and phospholipid (PL) fractions of the cells was determined. Reflecting the nature of the fat used, the corn oil treatment produced relatively higher concentrations of linoleic acid in the TG and PL fractions compared to the olive oil treatment, in which case the oleic acid level was influenced. Treatment of the cultured cells with components derived from oxidized corn oil or oxidized olive oil resulted in lower concentrations of linoleic an arachidonic acids in the PL moieties compared to the fresh fat controls. However, there were marked increases in arachidonic acid in the TG fractions of both the endothelial and muscle cells. These changes due to the DNUA from thermally oxidized fats indicate a distinct metabolic response to the derivatives formed during thermal oxidation of the fats. PMID:502761

  8. Feeding feedlot steers fish oil alters the fatty acid composition of adipose and muscle tissue.

    PubMed

    Wistuba, T J; Kegley, E B; Apple, J K; Rule, D C

    2007-10-01

    Sixteen steers (441±31.7kg initial body weight) consumed two high concentrate diets with either 0 or 3% fish oil to determine the impact of fish oil, an omega-3 fatty acid source, on the fatty acid composition of beef carcasses. Collected tissue samples included the Longissimus thoracis from the 6th to 7th rib section, ground 10th to 12th rib, liver, subcutaneous adipose tissue adjacent to the 12th rib, intramuscular adipose tissue in the 6th to 7th rib sections, perirenal adipose tissue, and brisket adipose tissue. Including fish oil in the diet increased most of the saturated fatty acids (P<0.01) and proportions of polyunsaturated fatty acids (P<0.06), and decreased (P<0.01) proportions of monounsaturated fatty acids. Dietary fish oil increased (P<0.01) levels of omega-3 fatty acids in sampled tissues, resulting in lower (P<0.01) omega-6:omega-3 ratios. The weight percentages of C20:5 and C22:6 in tissue may provide the recommended daily allowance for humans. Fish oil may have a role in beef niche marketing if there are no deleterious effects on consumer satisfaction. PMID:22061591

  9. Does membrane fatty acid composition modulate mitochondrial functions and their thermal sensitivities?

    PubMed

    Lemieux, H; Blier, P U; Tardif, J-C

    2008-01-01

    We investigated the effect of modifying fatty acid modification of heart mitochondrial membranes by dietary intervention on the functions and thermal sensitivity of electron transport system complexes embedded in the inner mitochondrial membrane. Four groups of rats were fed diets differing in their fat (coconut, olive or fish oil) and antioxidant (fish oil with or without probucol) contents. After 16 weeks of feeding, the coconut and olive oil groups had lower long-chain n-3 polyunsaturated fatty acids contents and a lower unsaturation index compared to both fish oil groups. These differences in fatty acid composition were not related to any differences in the mitochondrial respiration rate induced at Complexes I, II or IV, or to differences in their thermal sensitivity. The coconut oil group showed a lower mitochondrial affinity for pyruvate at 5 degrees C (k(mapp)=6.4+/-1.8) compared to any other groups (k(mapp)=3.8+/-0.5; 4.7+/-0.8; 3.6+/-1.1, for olive, fish oil and fish oil and probucol groups, respectively). At least in rat heart, our results do not support a major impact of the fatty acid composition of the mitochondrial membrane on the function of mitochondrial enzymatic complexes or on their temperature sensitivity. PMID:17993286

  10. Electrochemical Oxidation and Determination of Oxalic Acid at an Exfoliated Graphite-Polystyrene Composite Electrode

    PubMed Central

    Manea, Florica; Radovan, Ciprian; Corb, Ioana; Pop, Aniela; Burtica, Georgeta; Malchev, Plamen; Picken, Stephen; Schoonman, Joop

    2007-01-01

    An exfoliated graphite-polystyrene composite electrode was evaluated as an alternative electrode in the oxidation and the determination of oxalic acid in 0.1 M Na2SO4 supporting electrolyte. Using CV, LSV, CA procedures, linear dependences I vs. C were obtained in the concentrations range of oxalic acid between 0.5 to 3 mM, with LOD =0.05 mM, and recovery degree of 98%, without need of surface renewing between successive runs. The accuracy of the methods was evaluated as excellent comparing the detection results with that obtained using conventional KMnO4 titration method. In addition, the apparent diffusion coefficient of oxalic acid D was found to be around 2.89 · 10-8 cm2·s-1 by CA and CV.

  11. Isotope composition of sulphate in acid mine drainage as measure of bacterial oxidation

    USGS Publications Warehouse

    Taylor, B.E.; Wheeler, M.C.; Nordstrom, D.K.

    1984-01-01

    The formation of acid waters by oxidation of pyrite-bearing ore deposits, mine tailing piles, and coal measures is a complex biogeochemical process and is a serious environmental problem. We have studied the oxygen and sulphur isotope geochemistry of sulphides, sulphur, sulphate and water in the field and in experiments to identify sources of oxygen and reaction mechanisms of sulphate formation. Here we report that the oxygen isotope composition of sulphate in acid mine drainage shows a large variation due to differing proportions of atmospheric- and water-derived oxygen from both chemical and bacterially-mediated oxidation. 18O-enrichment of sulphate results from pyrite oxidation facilitated by Thiobacillus ferrooxidans in aerated environments. Oxygen isotope analysis may therefore be useful in monitoring the effectiveness of abatement programmes designed to inhibit bacterial oxidation. Sulphur isotopes show no significant fractionation between pyrite and sulphate, indicating the quantitative insignificance of intermediate oxidation states of sulphur under acid conditions. ?? 1984 Nature Publishing Group.

  12. Effect of soil acidity factors on yields and foliar composition of tropical root crops

    SciTech Connect

    Abruna-Rodriguez, F.; Vicente-Chandler, J.I. Rivera, E.; Rodriguez, J.

    1982-09-01

    Tropical root crops, a major source of food for subsistence farmers, varied in their sensitivity to soil acidity factors. Tolerance to soil acidity is an important characteristic of crops for the humid tropics where soils are often very acid and lime-scarce and expensive. Experiments on two Ultisols and an Oxisol showed that three tropical root crops differed markedly in sensitivity to soil acicity factors. Yams (Dioscorea alata L.) were very sensitive to soil acidity with yields on a Ultisol decreasing from 70% of maximum when Al saturation of the effective cation exchange capacity of the soil was 10 to 25% of maximum when Al saturation was 40%. On the other hand, cassava (Manihot esculenta Crantz) was very tolerant to high levels of soil acidity, yielding about 85% of maximum with 60% Al saturation. Taniers (Xanthosoma sp.) were intermediate between yams and cassava in their tolerance to soil acidity yielding about 60% of maximum with 50% Al saturation of the soil. Foliar composition of cassava was not affected by soil acidity levels and that of yams and taniers was also unaffected except for Ca content which decreased with decreasing soil pH and increasing Al saturation.Response of these tropical root crops to soil acidity components was far more striking on Ultisols than on the Oxisol. For yams, soils should be limed to about pH 5.5 with essentially no exhangeable Al/sup 3 +/ present whereas high yields of taniers can be obtained at about pH 4.8 with 20% exchangeable Al/sup 3 +/ and of cassava at pH as low as 4.5 with 60% exchangeable Al/sup 3 +/.

  13. ANALYTICAL VARIATION IN THE DETERMINATION OF THE FATTY ACID COMPOSITION OF STANDARD PREPARATIONS OF BRINE SHRIMP ARTEMIA: AN INTERLABORATORY EXERCISE

    EPA Science Inventory

    An international interlaboratory exercise was conducted to investigate the variability associated with the preparation and analysis of samples and the reporting of fatty acid composition data for tvo samples of Artemia supplied to the laboratories by the Artemia Reference Center ...

  14. Influence of dietary fat on the fatty acid composition of egg yolks and reproductive performance in the turkey 

    E-print Network

    Cornett, Bonita Manis

    1966-01-01

    INPLUENCE OF DIETARY FAT ON THE FATTY ACID COMPOSITION OF EGG YOLKS AND REPRODUCTIVE PERFORMANCE IN THE TURKEY A Thesis By BONITA MANIS CORNETT Submitted to the Graduate College of the Texas A&M University in partial fulfillpent... of the requirements for the degree of MASTER OF SCIENCE August 1966 Major Subject: Biochemistry and Nutrition INFLUENCE OF DIETARY FAT ON THE FATTY ACID COMPOSITION OF EGG YOLKS AND REPRODUCTIVE PERFORMANCE IN THE TURKEY A Thesis By BONITA MANIS CORNETT Appr...

  15. Fatty acid composition of spanish peanut oils as influenced by planting location, soil moisture conditions, variety, and season

    Microsoft Academic Search

    C. T. Young; R. E. Worthington; R. O. Hammons; R. S. Matlock; G. R. Waller; R. D. Morrison

    1974-01-01

    Nine varieties or strains of Spanish type peanuts were grown in the National Variety Test in Georgia and Oklahoma with and\\u000a without irrigation for two growing seasons. The oil of sound kernels was analyzed for fatty acid composition. Although no\\u000a consistent pattern was found, in general, variation in fatty acid composition due to variety was much less in Oklahoma than

  16. Liver transcriptome profile in pigs with extreme phenotypes of intramuscular fatty acid composition

    PubMed Central

    2012-01-01

    Background New advances in high-throughput technologies have allowed for the massive analysis of genomic data, providing new opportunities for the characterization of the transcriptome architectures. Recent studies in pigs have employed RNA-Seq to explore the transcriptome of different tissues in a reduced number of animals. The main goal of this study was the identification of differentially-expressed genes in the liver of Iberian x Landrace crossbred pigs showing extreme phenotypes for intramuscular fatty acid composition using RNA-Seq. Results The liver transcriptomes of two female groups (H and L) with phenotypically extreme intramuscular fatty acid composition were sequenced using RNA-Seq. A total of 146 and 180 unannotated protein-coding genes were identified in intergenic regions for the L and H groups, respectively. In addition, a range of 5.8 to 7.3% of repetitive elements was found, with SINEs being the most abundant elements. The expression in liver of 186 (L) and 270 (H) lncRNAs was also detected. The higher reproducibility of the RNA-Seq data was validated by RT-qPCR and porcine expression microarrays, therefore showing a strong correlation between RT-qPCR and RNA-Seq data (ranking from 0.79 to 0.96), as well as between microarrays and RNA-Seq (r=0.72). A differential expression analysis between H and L animals identified 55 genes differentially-expressed between groups. Pathways analysis revealed that these genes belong to biological functions, canonical pathways and three gene networks related to lipid and fatty acid metabolism. In concordance with the phenotypic classification, the pathways analysis inferred that linolenic and arachidonic acids metabolism was altered between extreme individuals. In addition, a connection was observed among the top three networks, hence suggesting that these genes are interconnected and play an important role in lipid and fatty acid metabolism. Conclusions In the present study RNA-Seq was used as a tool to explore the liver transcriptome of pigs with extreme phenotypes for intramuscular fatty acid composition. The differential gene expression analysis showed potential gene networks which affect lipid and fatty acid metabolism. These results may help in the design of selection strategies to improve the sensorial and nutritional quality of pork meat. PMID:23051667

  17. Effect of dietary fatty acid supplements, varying in fatty acid composition, on milk fat secretion in dairy cattle fed diets supplemented to less than 3% total fatty acids.

    PubMed

    Stoffel, C M; Crump, P M; Armentano, L E

    2015-01-01

    Dietary fatty acids can affect both milk fat yield and fatty acid (FA) composition. This relationship is well established when the dietary level of FA exceeds 3% of diet dry matter (DM). We could find no reports directly examining the effects of dietary FA profile on milk fat at levels below 3%. Twenty-four primiparous and 36 multiparous lactating cows were paired by production (1 high with 1 low, within parity) to form 30 experimental units. Pairs were fed 6 diets in five 6×6 balanced Latin squares with 21-d periods, and data were collected during the last 5d of each period. Two control diets were fed: a corn control diet (CC; 29% corn silage, 16% alfalfa silage, 19% corn grain, and 8% distillers grain on a DM basis) containing 1.8% FA; and a low-oil control diet (LOC; 9% corn silage, 35% alfalfa silage, 20% food-grade corn starch, and 8% corn gluten feed on a DM basis) containing 1.2% FA. A portion of the food-grade corn starch in LOC was replaced with 4 different FA supplements to create the 4 treatment diets. Treatments were 1.7% (DM basis) of a 50:50 blend of corn oil and high-linoleic safflower oil (LO), 1.7% high-oleic sunflower oil (OO), 1.7% palm oil (PO), or 1.8% calcium salts of palm fatty acids (PFA). The resultant diets were thus enriched in linoleic (LO), oleic (OO), or palmitic acid (PO and PFA). Dietary treatments did not affect dry matter intake. Addition of any of the fat sources to LOC resulted in increased milk yield, but milk fat yields and milk FA composition were variable for the different treatments. The LO treatment resulted in lower milk fat yield, fat concentration, and C16:0 yield but increased both trans-10 C18:1 and trans-10,cis-12 C18:2 yields compared with the other added FA treatments. Diets PO and PFA resulted in increased milk C16:0 yield and decreased total milk C18 yield compared with OO. Regression analysis revealed a negative coefficient for dietary linoleic acid content over basal (LOC) for both milk short-chain FA yield and C16:0 yield. Dietary linoleic acid content also had a positive coefficient for milk trans-10 C18:1 and trans-10,cis-12 conjugated linoleic acid yield. These results demonstrate that even when total dietary FA are below 3%, free oils rich in linoleic acid can reduce milk fat yield by reducing secretion of milk FA with fewer than 18 carbons. Fatty acid composition of fat supplements is important even at this low level of total dietary fat. PMID:25468700

  18. Effect of osmolyte or GdnHCl on volumetric properties of aqueous solutions containing cyclic dipeptides

    Microsoft Academic Search

    Pannur Venkatesu; Ming-Jer Lee; Ho-Mu Lin

    2008-01-01

    To understand the biomolecular interactions between osmolytes or guanidine hydrochloride (GdnHCl) with proteins, we have measured the densities (?) of a homologous series of cyclic dipeptides (CDs) in water and in aqueous solutions of osmolytes or GdnHCl through the high precision vibrating tube digital densitometer up to saturated state, as a function of solute concentrations at 25°C under atmospheric pressure.

  19. String Method with Collective variables from Normal Modes : Application to Alanine Dipeptide

    E-print Network

    Izaguirre, Jesús A.

    String Method with Collective variables from Normal Modes : Application to Alanine Dipeptide as the reaction coordinates. This choice is based on the observation that normal mode analysis can provide that the choice of the normal modes confers simplifications in the string method itself due to the linear

  20. Enantiomeric interactions between liquid crystals and organized monolayers of tyrosine-containing dipeptides.

    PubMed

    Bai, Yiqun; Abbott, Nicholas L

    2012-01-11

    We have examined the orientational ordering of nematic liquid crystals (LCs) supported on organized monolayers of dipeptides with the goal of understanding how peptide-based interfaces encode intermolecular interactions that are amplified into supramolecular ordering. By characterizing the orientations of nematic LCs (4-cyano-4'-pentylbiphenyl and TL205 (a mixture of mesogens containing cyclohexane-fluorinated biphenyls and fluorinated terphenyls)) on monolayers of l-cysteine-l-tyrosine, l-cysteine-l-phenylalanine, or l-cysteine-l-phosphotyrosine formed on crystallographically textured films of gold, we conclude that patterns of hydrogen bonds generated by the organized monolayers of dipeptides are transduced via macroscopic orientational ordering of the LCs. This conclusion is supported by the observation that the ordering exhibited by the achiral LCs is specific to the enantiomers used to form the dipeptide-based monolayers. The dominant role of the -OH group of tyrosine in dictating the patterns of hydrogen bonds that orient the LCs was also evidenced by the effects of phosphorylation of the tyrosine on the ordering of the LCs. Overall, these results reveal that crystallographic texturing of gold films can direct the formation of monolayers of dipeptides with long-range order, thus unmasking the influence of hydrogen bonding, chirality, and phosphorylation on the macroscopic orientational ordering of LCs supported on these surfaces. These results suggest new approaches based on supramolecular assembly for reporting the chemical functionality and stereochemistry of synthetic and biological peptide-based molecules displayed at surfaces. PMID:22091988

  1. Chromatographic retention and thermodynamics of adsorption of dipeptides on a chiral crown ether stationary phase.

    PubMed

    Asnin, Leonid; Sharma, Kavita; Park, Se Won

    2011-11-01

    The enantioselective adsorption of several dipeptides on the crown ether-based stationary phase ChiroSil RCA(+) was studied by means of the linear chromatography method. The retention of analytes was measured with acidified water-methanol mobile phases with varied concentration of methanol (from 60 to 90%, v/v) at different temperatures. Thermodynamic characteristics of adsorption were determined and analyzed applying extrathermodynamic relationships. A considerable difference in adsorption mechanisms of dipeptides with a chiral and achiral N-terminal fragment was proved. An explanation to this fact was proposed assuming that the enantiorecognition of the dipeptides of the first type occurred through the interaction of side groups of the N-terminus with the chiral cavity formed by the crown ether ring. The enantiorecognition of the dipeptides of the second type occurs through the interaction of the C-terminal residue with the side groups of the crown ether moiety. The study also demonstrates how extrathermodynamic concepts can be used for obtaining additional information about retention mechanisms from a limited amount of chromatographic data. PMID:21993964

  2. Enantiomeric Interactions between Liquid Crystals and Organized Monolayers of Tyrosine-Containing Dipeptides

    PubMed Central

    Bai, Yiqun; Abbott, Nicholas L.

    2011-01-01

    We have examined the orientational ordering of nematic liquid crystals (LCs) supported on organized monolayers of dipeptides with the goal of understanding how peptide-based interfaces encode intermolecular interactions that are amplified into supramolecular ordering. By characterizing the orientations of nematic LCs (4-cyano-4?-pentylbiphenyl (5CB) and TL205 (a mixture of mesogens containing cyclohexane-fluorinated biphenyls and fluorinated terphenyls)) on monolayers of either L-cysteine-L-tyrosine, L-cysteine-L-phenylalanine or L-cysteine-L-phosphotyrosine formed on crystallographically textured films of gold, we conclude that patterns of hydrogen bonds generated by the organized monolayers of dipeptides are transduced via macroscopic orientational ordering of the LCs. This conclusion is supported by the observation that the ordering exhibited by the achiral LCs is specific to the enantiomers used to form the dipeptide-based monolayers. The dominate role of the –OH group of tyrosine in dictating the patterns of hydrogen bonds that orient the LCs was also evidenced by the effects of phosphorylation of the tyrosine on the ordering of the LCs. Overall, these results reveal that crystallographic texturing of gold films can direct the formation of monolayers of dipeptides with long-range order, thus unmasking the influence of hydrogen bonding, chirality and phosphorylation on the macroscopic orientational ordering of LCs supported on these surfaces. These results suggest new approaches based on supramolecular assembly for reporting the chemical functionality and stereochemistry of synthetic and biological peptide-based molecules displayed at surfaces. PMID:22091988

  3. Analysis of the correlation between dipeptides and taste differences among soy sauces by using metabolomics-based component profiling.

    PubMed

    Yamamoto, Shinya; Shiga, Kazuki; Kodama, Yukako; Imamura, Miho; Uchida, Riichiro; Obata, Akio; Bamba, Takeshi; Fukusaki, Eiichiro

    2014-07-01

    Characterizing the relationships between the components and taste differences among soy sauces can help evaluate and improve the quality of soy sauces. Although previous studies have reported that certain taste-active dipeptides, the relationships between taste differences and dipeptides of soy sauces are unknown. Therefore, our objective in this study was to investigate the correlations between the dipeptides and the taste differences among soy sauces. To analyze the dipeptides, we constructed an analytical method using liquid chromatography/tandem mass spectrometry (LC/MS/MS) in multiple reaction monitoring mode. Based on this method, we detected 237 dipeptides, the largest number ever detected in soy sauce research. Next, orthogonal projections to latent structures regressions were performed. The data matrix of components, including dipeptides and other low-molecular-weight hydrophilic components obtained from gas chromatography/mass spectrometry (GC/MS), served as explanatory variables (366 in total), whereas a sensory data matrix obtained using quantitative descriptive analysis served as the response variable. The accuracy of models for the sweetness and saltiness differences constructed using the LC/MS/MS and GC/MS data matrix were higher than did models constructed using only the GC/MS data matrix. As a result of investigation of the correlation between the dipeptides and taste differences among soy sauces by using variable importance in the projection (VIP) score, many dipeptides showed the high correlation with taste differences. Specifically, Ile-Gln, Pro-Lys, Ile-Glu, Thr-Phe, and Leu-Gln showed the high VIP score on sweet differences. This study is the first report that reveals the correlations between the dipeptides and taste differences among soy sauces. PMID:24491915

  4. Terpene composited lipid nanoparticles for enhanced dermal delivery of all-trans-retinoic acids.

    PubMed

    Charoenputtakun, Ponwanit; Pamornpathomkul, Boonnada; Opanasopit, Praneet; Rojanarata, Theerasak; Ngawhirunpat, Tanasait

    2014-01-01

    In the present study, terpene composited lipid nanoparticles and lipid nanoparticles were developed and evaluated for dermal delivery of all-trans-retinoic acids (ATRA). Terpene composited lipid nanoparticles and lipid nanoparticles were investigated for size, size distribution, zeta potential, entrapment efficiency, photostability, and cytotoxicity. In vitro skin permeation of ATRA lipid formulations were also evaluated. To explore the ability of lipid nanocarriers to target the skin, the distribution of rhodamine B base in the skin was investigated using confocal laser scanning microscopy (CLSM). The results indicated that the physicochemical characteristics of terpene composited lipid nanoparticles influenced skin permeability. All lipid nanocarriers significantly protected ATRA from photodegradation and were non-toxic to normal human foreskin ?broblast cells in vitro. Solid lipid nanoparticles containing 10% limonene (10% L-SLN) had the highest ATRA skin permeability. Terpene composited SLN and nanostructured lipid carriers (NLC) showed higher epidermal permeation of rhodamine B across the skin based on CLSM image analysis. Our study suggests that terpene composited SLN and NLC can be potentially used as dermal drug delivery carriers for ATRA. PMID:24805206

  5. Characterization of lipid and fatty acids composition of Chlorella zofingiensis in response to nitrogen starvation.

    PubMed

    Zhu, Shunni; Wang, Yajie; Shang, Changhua; Wang, Zhongming; Xu, Jingliang; Yuan, Zhenhong

    2015-08-01

    Cellular biochemical composition of the microalga Chlorella zofingiensis was studied under favorable and nitrogen starvation conditions, with special emphasis on lipid classes and fatty acids distribution. When algal cells were grown in nitrogen-free medium (N stress), the increase in the contents of lipid and carbohydrate while a decrease in protein content was detected. Glycolipids were the major lipid fraction (50.7% of total lipids) under control condition, while neutral lipids increased to be predominant (86.7% of total lipids) under N stress condition. Triacylglycerol (TAG) content in N stressed cells was 27.3% dw, which was over three times higher than that obtained under control condition. Within neutral lipids fraction, monounsaturated fatty acids (MUFA) were the main group (40.6%) upon N stress, in which oleic acid was the most representative fatty acids (34.5%). Contrarily, glycolipids and phospholipids showed a higher percentage of polyunsaturated fatty acids (PUFA). Lipid quality assessment indicated the potential of this alga as a biodiesel feedstock when its neutral lipids were a principal lipid fraction. The results demonstrate that the neutral lipids content is key to determine the suitability of the microalga for biodiesel, and the stress cultivation is essential for lipid quality. PMID:25782619

  6. Polyunsaturated fatty acid composition of maternal diet and erythrocyte phospholipid status in Chilean pregnant women.

    PubMed

    Bascuñán, Karla A; Valenzuela, Rodrigo; Chamorro, Rodrigo; Valencia, Alejandra; Barrera, Cynthia; Puigrredon, Claudia; Sandoval, Jorge; Valenzuela, Alfonso

    2014-11-01

    Chilean diets are characterized by a low supply of n-3 polyunsaturated fatty acids (n-3 PUFA), which are critical nutrients during pregnancy and lactation, because of their role in brain and visual development. DHA is the most relevant n-3 PUFA in this period. We evaluated the dietary n-3 PUFA intake and erythrocyte phospholipids n-3 PUFA in Chilean pregnant women. Eighty healthy pregnant women (20-36 years old) in the 3rd-6th month of pregnancy were included in the study. Dietary assessment was done applying a food frequency questionnaire, and data were analyzed through the Food Processor SQL® software. Fatty acids of erythrocyte phospholipids were assessed by gas-liquid chromatography. Diet composition was high in saturated fat, low in mono- and PUFA, high in n-6 PUFA (linoleic acid) and low in n-3 PUFA (alpha-linolenic acid and DHA), with imbalance in the n-6/n-3 PUFA ratio. Similar results were observed for fatty acids from erythrocyte phospholipids. The sample of Chilean pregnant women showed high consumption of saturated fat and low consumption of n-3 PUFA, which is reflected in the low DHA content of erythrocyte phospholipids. Imbalance between n-6/n-3 PUFA could negatively affect fetal development. New strategies are necessary to improve n-3 PUFA intake throughout pregnancy and breast feeding periods. Furthermore, it is necessary to develop dietary interventions to improve the quality of consumed foods with particular emphasis on n-3 PUFA. PMID:25386693

  7. Characterization of the bovine gene LIPE and possible influence on fatty acid composition of meat

    PubMed Central

    Goszczynski, Daniel Estanislao; Mazzucco, Juliana Papaleo; Ripoli, María Verónica; Villarreal, Edgardo Leopoldo; Rogberg-Muñoz, Andrés; Mezzadra, Carlos Alberto; Melucci, Lilia Magdalena; Giovambattista, Guillermo

    2014-01-01

    LIPE is an intracellular neutral lipase, which is capable of hydrolyzing a variety of esters and plays a key role in the mobilization of fatty acids from diacylglycerols. The objectives of this study were to characterize the genetic polymorphism of bovine LIPE gene and to evaluate the possible association between three SNPs in the coding regions of this gene with the fatty acid composition of meat in a cattle population. Forty-three unrelated animals from different cattle breeds were re-sequenced and 21 SNPs were detected over approximately 2600 bp, five of these SNPs were novel. Three SNPs were selected, on the basis of evolutionary conservation, to perform validation and association studies in a crossbred cattle population. Our results may suggest a possible association of SNP1 with contents of oleic acid and total monounsaturated fatty acids (p < 0.01), and SNP2 and SNP3 with Heneicosylic acid content (p < 0.01), may be helpful to improve the quality of meat and improve health. PMID:25606458

  8. Diffusion dialysis. Effect of membrane composition on acid/salt separation

    SciTech Connect

    Narebska, A.; Warszawski, A. (Nicolaus Copernicus Univ., Torun (Poland))

    1992-05-01

    Diffusion dialysis is an energy-saving separation technique. In order to highlight the relationship between membrane composition and ability to separate acid/salt mixtures by diffusion dialysis, a few anion-exchange membranes were examined. Experiments on solubility/diffusivity phenomena were carried out in contact with hydrochloric acid and sodium chloride solutions (single- and two-solute experiments). Computations using Glueckauf and Tye models have indicated high nonuniformity in the distribution of fixed charged within the membranes and different accessibilities of the internal membrane volumes for the acid and salt. The Neosepta AFN-7 membrane (Tokuymam Soda Co.) has proved effective in differentiating the permeants by sorption (k{sub HCl}/k{sub NaCl} {approx} 2) and diffusivity ({bar D}{sub HCl}/{bar D}{sub NaCl} up to 10). This membrane is also the only one which, when in contact with two-solutes solutions, absorbs the acid preferentially to the salt. For this membrane the preferential sorption and transport of the acid depends not only on the physical structure of the membrane but also on the chemical nature of the polymer which contains pyridine moieties.

  9. Factors influencing cell fatty acid composition and A40926 antibiotic complex production in Nonomuraea sp. ATCC 39727.

    PubMed

    Jovetic, Srdjan; Feroggio, Marina; Marinelli, Flavia; Lancini, Giancarlo

    2008-10-01

    A40926 is a glycopeptide antibiotic complex consisting of several structurally related factors. It is produced by fermentation of Nonomuraea sp. ATCC 39727 and the complex components differ in the structure of the fatty acid moiety linked to the aminoglucuronic acid unit. In previous work, we observed that the production of single factors in glycopeptide antibiotic complexes could be selectively enhanced by the addition of suitable precursors to the culture medium. In this contribution, we examine the effects of branched amino acid addition to fermentation of Nonomuraea sp. in a chemically defined minimal medium. The changes in the composition of cell fatty acids correlate to the fatty acid distribution within the A40926 complex in diverse cultivation conditions. Nonomuraea sp. prefers isobutyric, butyric and propionic acids as initiators of fatty acid biosynthesis. The relative amount of the produced fatty acids is significantly influenced by the availability of intermediates or final products from the amino acid catabolic pathways. Antibiotic complex composition closely reflects the cell fatty acid pattern, in agreement with the assumption that the antibiotic fatty acid moieties are synthesized by shortening the chain of cell fatty acids. PMID:18651189

  10. Effects of ensiling processes and antioxidants on fatty acid concentrations and compositions in corn silages

    PubMed Central

    2013-01-01

    Background Corn silage is the main dietary component used for ruminant breeding in China and is an important dietary source of fatty acids for these animals. However, little is known regarding effective means to protect the fatty acid (FA) contents in silages. In this study, we examined the changes in FA contents and compositions during corn ensiling and screened several antioxidants for their inhibition of lipid oxidation during corn ensiling. Methods We conducted two different experiments. In Experiment 1, corn was ensiled in 30 polyethylene bottles (bottle volume: 1 L, silage density: 600 g/dm3) and three bottles were opened at 0.5 d, 1 d, 1.5 d, 2 d, 2.5 d, 3 d, 5 d, 7 d, 14 d, and 28 d after ensiling. In Experiment 2, corn was treated with various antioxidants: (1) No additives (CK); (2) BHA (Butylated hydroxyanisole); (3) TBHQ (Tertiary butyl hydroquinone); (4) TPP (Tea polyphenols); and (5) VE (Vitamin E). These treatments were applied at 50 mg/kg and 100 mg/kg of fresh weight with each treatment replicated 3 times. Results During ensiling in Experiment 1, saturated fatty acids (SFA; C16:0 and C18:0) and malondialdehyde (MDA) contents tended to increase, whereas unsaturated fatty acids (UFA; C18:1, C18:2 and C18:3) tended to decrease. However, these changes were only significant on the first 2 days of ensiling. In Experiment 2, all of the antioxidants tested affected the total FA contents and those of unsaturated fatty acids (C18:1, C18:2 and C18:3) and MDA. The effects of TBHQ and TPP were greater than those of the other antioxidants. Conclusions The reduced total FA contents in corn silages were due to unsaturated fatty acids’ oxidation during the early stages of ensiling. Adding an antioxidant could prevent fatty acids’ oxidation in corn silages. PMID:24304647

  11. Muramyl Dipeptide Enhances Lipopolysaccharide-Induced Osteoclast Formation and Bone Resorption through Increased RANKL Expression in Stromal Cells

    PubMed Central

    Ishida, Masahiko; Kimura, Keisuke; Sugisawa, Haruki; Aonuma, Tomo; Takada, Haruhiko; Takano-Yamamoto, Teruko

    2015-01-01

    Lipopolysaccharide (LPS) is bacterial cell wall component capable of inducing osteoclast formation and pathological bone resorption. Muramyl dipeptide (MDP), the minimal essential structural unit responsible for the immunological activity of peptidoglycans, is ubiquitously expressed by bacterium. In this study, we investigated the effect of MDP in LPS-induced osteoclast formation and bone resorption. LPS was administered with or without MDP into the supracalvariae of mice. The number of osteoclasts, the level of mRNA for cathepsin K and tartrate-resistant acid phosphatase (TRAP), the ratio of the bone destruction area, the level of tartrate-resistant acid phosphatase form 5b (TRACP 5b), and C-terminal telopeptides fragments of type I collagen as a marker of bone resorption in mice administrated both LPS and MDP were higher than those in mice administrated LPS or MDP alone. On the other hand, MDP had no effect on osteoclastogenesis in parathyroid hormone administrated mice. MDP enhanced LPS-induced receptor activator of NF-?B ligand (RANKL) expression and Toll-like receptor 4 (TLR4) expression in vivo and in stromal cells in vitro. MDP also enhanced LPS-induced mitogen-activated protein kinase (MAPK) signaling, including ERK, p38, and JNK, in stromal cells. These results suggest that MDP might play an important role in pathological bone resorption in bacterial infection diseases. PMID:26000311

  12. Self-etching primer vs phosphoric acid: an alternative concept for composite-to-enamel bonding.

    PubMed

    Hannig, M; Reinhardt, K J; Bott, B

    1999-01-01

    The purpose of this in vitro study was (1) to investigate the composite-to-enamel bond strength and (2) to analyze the marginal adaptation of resin composite restorations in class 2 cavities using three self-etching priming agents in comparison to conventional phosphoric acid etching and bonding application. In the first part of the study 24 extracted bovine incisors were embedded in acrylic resin and ground flat with 800-grit paper. The following three self-etching priming agents/composite resins were applied to the enamel surfaces of six teeth each: Clearfil Liner Bond 2/Clearfil AP-X (Group I), Etch & Prime 3.0/Degufill mineral (Group II), Resulcin AquaPrime + MonoBond/Ecusit (Group III). In Group IV Ecusit-Mono/Ecusit was used after enamel etching with phosphoric acid (37%). Shear bond strength values measured on a T22 K testing machine at a crosshead speed of 1 mm/min were: 24.2 +/- 3.0 MPa (Group I), 21.9 +/- 1.4 MPa (II), 34.0 +/- 3.6 MPa (III), and 26.3 +/- 1.8 MPa (IV). ANOVA revealed significant (P < 0.05) differences in shear bond strength between groups, except comparison of Group I and II, and Group I and IV. In the second part of the study 24 standardized class 2 cavity preparations with the approximal box extending 1 mm above the CEJ were prepared in extracted human molars. Enamel margins were beveled and the teeth were divided into four groups of six teeth each. Cavities were restored using the self-etching priming agents Clearfil Liner Bond 2 (Group I), Etch & Prime 3.0 (Group II), and Resulcin AquaPrime + MonoBond (Group III). In Group IV composite resin restorations were placed after 37% phosphoric acid etching and bonding application (Ecusit-Mono). Quantitative SEM analysis of the marginal adaptation of the restorations after thermocycling (5-55 degrees C, 2500 cycles) and mechanical loading (100 N, 500,000 cycles) revealed excellent, gap-free margins in 91.2% (Group I), 93.0% (Group II), 92.0% (Group III), and 92.5% (Group IV) of the restorations' approximal area. There were no statistically significant differences between the four groups (P < 0.05). In conclusion, results of the present in vitro study indicate that use of self-etching primers may be an alternative to conventional phosphoric acid pre-treatment in composite-to-enamel bonding restorative techniques. PMID:10530279

  13. Thermal properties of extruded injection-molded poly (lactic acid) and milkweed composites: degradation kinetics and enthalpic relaxation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Currently, most polymer composites utilize petroleum-based materials that are non-degradable and difficult to recycle or incur substantial cost for disposal. Green composites can be used in nondurable limited applications. In order to determine the degree of compatibility between Poly (lactic Acid...

  14. Influence of alkali treatment on the interfacial and physico-mechanical properties of industrial hemp fibre reinforced polylactic acid composites

    Microsoft Academic Search

    M. S. Islam; K. L. Pickering; N. J. Foreman

    2010-01-01

    The focus of this work was to produce short (random and aligned) and long (aligned) industrial hemp fibre reinforced polylactic acid (PLA) composites by compression moulding. Fibres were treated with alkali to improve bonding with PLA. The percentage crystallinity of PLA in composites was found to be higher than that for neat PLA and increased with alkali treatment of fibres

  15. Comparison of fatty acid composition in major lipid classes of the dominant benthic invertebrates of the Yenisei river

    Microsoft Academic Search

    N. N. Sushchik; M. I. Gladyshev; A. V. Moskvichova; O. N. Makhutova; G. S. Kalachova

    2003-01-01

    The composition and content of fatty acids (FAs) in total lipids, triacylglycerols (TAG) and polar lipids (PL) in dominant groups of benthic invertebrates: gammarids (Gammaridae, Amphipoda), chironomid larvae (Chironomidae, Diptera), caddisfly larvae (Trichoptera) and mayfly larvae (Ephemeroptera) were studied in the Yenisei river. For the first time data on the FA composition of species belonging to Trichoptera (Insecta) are presented.

  16. Efficacy of a Novel Whey Protein Gel Complex to Increase the Unsaturated Fatty Acid Composition of Bovine Milk Fat

    Microsoft Academic Search

    S. M. Carroll; E. J. DePeters; M. Rosenberg

    2006-01-01

    A novel whey protein emulsion gel (WPEG) complex was developed to protect dietary unsaturated fatty acids from rumen biohydrogenation with the goal of modifying the fatty acid composition of milk fat. Three experiments were conducted with WPEG complexes made from either whey protein concentrate containing 80% crude protein, whey protein isolate, or whey pro- tein concentrate high-gel capacity. Each experiment

  17. Chemical composition of acid–base fractions separated from biooil derived by fast pyrolysis of chicken manure

    Microsoft Academic Search

    Dharani D. Das; Morris I. Schnitzer; Carlos M. Monreal; Paul Mayer

    2009-01-01

    Our earlier investigations on the chemical composition of biooils derived by the fast pyrolysis of chicken manure revealed the presence of more than 500 compounds. In order to simplify this heterogeneous and complex chemical system, we produced four biooil fractions namely strongly acidic fraction A, weakly acidic fraction B, basic fraction C and neutral fraction D on the basis of

  18. The Fatty Acid Composition of Maternal Diet Affects the Response to Excitotoxic Neural Injury in Neonatal Rat Pups

    Microsoft Academic Search

    Pablo Valencia; Jane D Carver; Lance E Wyble; Valerie J Benford; Enid Gilbert-Barness; Doris A Wiener; Christopher Phelps

    1998-01-01

    Fatty acids and their derivatives play a role in the response to neural injury. The effects of prenatal and postnatal dietary fatty acid composition on excitotoxic neural injury were investigated in neonatal rat pups. Dams were fed during gestation and lactation a diet whose fat source was either corn oil or menhaden fish oil. On postnatal day 3, litters were

  19. A Biochemical GC-MS Application for the Organic Chemistry Laboratory: Determination of Fatty Acid Composition of Arabidopsis thaliana Lipids

    Microsoft Academic Search

    Jared D. Bender; Arthur J. Catino III; Kenneth R. Hess; Michael E. Lassman; Phyllis A. Leber; Michael D. Reinard; Neil A. Strotman; Carl S. Pike

    2000-01-01

    A biochemical application of GC-MS in which students determine the qualitative and quantitative lipid composition of plant leaf samples is described. There are four facets of this project: (i) synthesis and characterization of individual fatty acid methyl esters (FAMEs) as standards for GC-MS analysis, (ii) isolation of the fatty acids of Arabidopsis thaliana leaves, both wild type and mutants, as

  20. The influence of dietary fatty acid composition on the respiratory and cardiovascular physiology of Adriatic sturgeon (Acipenser naccarii): a review

    Microsoft Academic Search

    D. J. McKenzie; G. Piraccini; C. Agnisola; J. F. Steffensen; P. Bronzi; C. L. Bolis; B. Tota; E. W. Taylor

    1999-01-01

    Summary This paper reviews evidence that the fatty acid composition of dietary lipids influences the respiratory and cardiovascular physiology of Adriatic sturgeon (Acipenser naccarii) and, thereby, their tolerance of the stress of hypoxia. Sturgeon fed a commercial diet enriched in fish oil (menhaden oil as 15% of dry feed weight), with an elevated content of highly unsaturated fatty acids of

  1. Changes in Plasma Amino Acid Levels Do Not Predict Satiety and Weight Loss on Diets with Modified Macronutrient Composition

    Microsoft Academic Search

    Mikhail S. Koren; Jonathan Q. Purnell; Patricia A. Breen; Colleen C. Matthys; Holly S. Callahan; Kaatje E. Meeuws; Verna R. Burden; David S. Weigle

    2007-01-01

    Objective: Serotonin mediates satiety in the central nervous system. Brain serotonin content depends on the plasma ratio of tryptophan (Trp) to large neutral amino acids (LNAA) and may be affected by diet composition. We examined whether high-carbohydrate or high-protein diets induce satiety and weight loss by altering plasma concentrations of these amino acids. Methods: In study 1 (n = 16,

  2. Effect of different cooking methods on the oxidation, proximate and fatty acid composition of silver catfish ( Rhamdia quelen) fillets

    Microsoft Academic Search

    Jucieli Weber; Vivian C. Bochi; Cristiane P. Ribeiro; André de M. Victório; Tatiana Emanuelli

    2008-01-01

    The influence of seven cooking methods (boiling, conventional baking, microwave baking, grilling, deep-frying in soybean oil, canola oil, or partially hydrogenated vegetable oil) on the oxidation, proximate and fatty acid composition of silver catfish (Rhamdia quelen) fillets was evaluated. All the treatments reduced moisture and increased the protein content. The free fatty acid content of the fillets was significantly reduced

  3. Composition of fatty acids, triacylglycerols and polar compounds of different walnut varieties (Juglans regia L.) from Tunisia.

    PubMed

    Bouabdallah, I; Bouali, I; Martinez-Force, E; Albouchi, A; Perez Camino, M C; Boukhchina, S

    2014-01-01

    The chemical composition (total oil content, fatty acids, triacylglycerols (TAGs) and polar compounds) of six walnuts (Juglans regia L.) cultivars (Lauzeronne, Franquette, Hartley, Local pt, Local gd and Parisienne) collected from Mateur (north of Tunisia) was evaluated. The major fatty acids found in the walnut oils are linoleic acid (60.42-65.77%), oleic acid (13.21-19.94%) and linolenic acid (7.61-13%). The TAG species were mainly composed of trilinolein (LLL), dilinoleoyl-linolenoyl-glycerol, dilinoleoyl-oleoyl-glycerol and palmitoyl-dilinoleoyl-glycerol classes. The results revealed that Local pt variety has the highest level of oil (62.56%), linoleic acid (65.77%) and LLL (33.48%). Significant differences among oil samples were observed, therefore showing a great variability in the oil composition among cultivars. PMID:25142132

  4. Dissolution of cerium(IV)-lanthanide(III) oxides: Comparative effect of chemical composition, temperature, and acidity

    SciTech Connect

    Horlait, D.; Clavier, N.; Szenknect, S.; Dacheux, N.; Dubois, V. [ICSM, CEA CNRS UM2 ENSCM, UMR 5257, F-30207 Bagnols Sur Ceze, (France)

    2012-03-15

    The dissolution of Ce{sub 1-x}Ln{sub x}O{sub 2-x/2} solid solutions was undertaken in various acid media in order to evaluate the effects of several physicochemical parameters such as chemical composition, temperature, and acidity on the reaction kinetics. The normalized dissolution rates (R{sub L,0}) were found to be strongly modified by the trivalent lanthanide incorporation rate, due to the presence of oxygen vacancies decreasing the samples cohesion. Conversely, the nature of the trivalent cation considered only weakly impacted the R{sub L,0} values. The dependence of the normalized dissolution rates on the temperature then appeared to be of the same order of magnitude than that of chemical composition. Moreover, it allowed determining the corresponding activation energy (E{sub A} ? 60-85 kJ.mol{sup -1}) which accounts for a dissolution driven by surface-controlled reactions. A similar conclusion was made regarding the acidity of the solution: the partial order related to (H{sub 3}O{sup +}) reaching about 0.7. Finally, the prevailing effect of the incorporation of aliovalent cations in the fluorite-type CeO{sub 2} matrix on the dissolution kinetics precluded the observation of slight effects such as those linked to the complexing agents or to the crystal structure of the samples. (authors)

  5. Bulk, surface properties and water uptake mechanisms of salt/acid amorphous composite systems.

    PubMed

    Bianco, Stefano; Tewes, Frederic; Tajber, Lidia; Caron, Vincent; Corrigan, Owen I; Healy, Anne Marie

    2013-11-01

    Developing amorphous pharmaceuticals can be desirable due to advantageous biopharmaceutical properties. Low glass transition temperature (Tg) amorphous drugs can be protected from crystallisation by mixing with high Tg excipients, such as polymers, or with salt forms. However, both polymers and salts can enhance the water uptake. The aim of this study was to formulate physico-chemically stable amorphous materials, by co-processing different proportions of sulfathiazole and its sodium salt to produce an optimum ratio, characterised by the best physical stability and lowest hygroscopicity. Both sulfathiazole and salt amorphised upon spray drying. At room temperature, sulfathiazole crystallised within 1h at <5% relative humidity while the salt deliquesced when exposed to ambient humidity conditions. In the case of composite systems, FTIR spectroscopy, thermal and surface analysis suggested interactions with an acid:salt stoichiometry of 1:2. Increasing proportions of salt raised the Tg, enhancing the storage stability, however this was opposed by an enhanced hygroscopicity. The water uptake mechanism within the different amorphous systems, analysed by fitting the water sorption isotherms with the Young and Nelson equation, was dependent on the ratio employed, with the salt and the acid facilitating absorption and adsorption, respectively. Tuning the properties of amorphous salt/acid composites by optimising the ratio appears potentially promising to improve the physical stability of amorphous formulations. PMID:23948137

  6. Prediction of Aptamer-Target Interacting Pairs with Pseudo-Amino Acid Composition

    PubMed Central

    Huang, Guo-Hua; Cui, Wei-Ren; Zhang, Ning; Cai, Yu-Dong

    2014-01-01

    Aptamers are oligonucleic acid or peptide molecules that bind to specific target molecules. As a novel and powerful class of ligands, aptamers are thought to have excellent potential for applications in the fields of biosensing, diagnostics and therapeutics. In this study, a new method for predicting aptamer-target interacting pairs was proposed by integrating features derived from both aptamers and their targets. Features of nucleotide composition and traditional amino acid composition as well as pseudo amino acid were utilized to represent aptamers and targets, respectively. The predictor was constructed based on Random Forest and the optimal features were selected by using the maximum relevance minimum redundancy (mRMR) method and the incremental feature selection (IFS) method. As a result, 81.34% accuracy and 0.4612 MCC were obtained for the training dataset, and 77.41% accuracy and 0.3717 MCC were achieved for the testing dataset. An optimal feature set of 220 features were selected, which were considered as the ones that contributed significantly to the interacting aptamer-target pair predictions. Analysis of the optimal feature set indicated several important factors in determining aptamer-target interactions. It is anticipated that our prediction method may become a useful tool for identifying aptamer-target pairs and the features selected and analyzed in this study may provide useful insights into the mechanism of interactions between aptamers and targets. PMID:24466214

  7. Swelling and dye sorption studies of acrylamide\\/2-acrylamido-2-methyl-1-propanesulfonic acid\\/bentonite highly swollen composite hydrogels

    Microsoft Academic Search

    Semiha Kundakci; Ömer Bar?? Üzüm; Erdener Karada?

    2008-01-01

    Water uptake and the sorption properties of polyelectrolyte composite hydrogels made by the polymerization of acrylamide (AAm) with 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) and a clay such as bentonite (Bent) were investigated as a function of composition to find materials with swelling and dye sorption properties. Highly swollen AAm\\/AMPS hydrogels and AAm\\/AMPS\\/Bent composite hydrogels were prepared by free radical solution polymerization in

  8. Poly(acrylic acid)wrapped multi-walled carbon nanotubes composite solubilization in water: definitive spectroscopic properties

    Microsoft Academic Search

    Aihua Liu; Itaru Honma; Masaki Ichihara; Haoshen Zhou

    2006-01-01

    A non-conjugated polymeric poly(acrylic acid) (PAA) is shown to efficiently form a stable composite with multi-walled carbon nanotubes (MWNTs). The prepared PAA-wrapped MWNTs composite is readily soluble and stable in water. The PAA-MWNTs composite exhibits interesting optical properties. FT-IR spectra show that the characteristic peaks for MWNTs are unchanged, and new chemical bonds are not formed in PAA-MWNTs, indicating that

  9. The Effect of Arylboronic Acid Treatment of Carbon Fiber on the Mechanical and Tribological Properties of PA66 Composites

    Microsoft Academic Search

    Gang Tang; Daofang Chang; Gaofeng Wei; Houjun Lu; Wei Yan; Bingsheng Liu

    2012-01-01

    PA66 composites filled with surface-treated carbon fiber were prepared by twin-screw extruder in order to study the influence of carbon fiber surface arylboronic acid treatment on the mechanical and tribological behavior of the PA66 composites (CF\\/PA66). The mechanical property, friction and wear tests of the composites with untreated and treated carbon fiber were performed and the worn surface morphology was

  10. Chopped glass and recycled newspaper as reinforcement fibers in injection molded poly(lactic acid) (PLA) composites: A comparative study

    Microsoft Academic Search

    Masud S. Huda; Lawrence T. Drzal; Amar K. Mohanty; Manjusri Misra

    2006-01-01

    Natural\\/bio-fibers are replacing synthetic reinforcements traditionally used for the preparation of the environmentally friendly composites. Composite materials are also replacing conventional materials in various fields due to their ease of processability. Chopped glass fiber- and recycled newspaper cellulose fiber (RNCF)- reinforced poly(lactic acid) (PLA) composites were processed using a full size twin-screw extruder and an injection molder. Additionally, a glass-reinforced

  11. Chemometric discrimination among wild and cultured age-0 largemouth bass, black crappies, and white crappies based on fatty acid composition.

    PubMed

    Tritt, Kay L; O'Bara, Christopher J; Wells, Martha J M

    2005-06-29

    The potential to distinguish juvenile wild from cultured fishes and to discriminate among juvenile fishes by species based on fatty acid composition was demonstrated. Statistical approaches to data evaluation included analysis of variance, correlation analysis, principal component analysis (PCA), and quadratic discriminant analysis (QDA). Differences were determined between wild and cultured fishes both within and between species and between hatcheries. Fatty acid compositions were compared among individual (not composited) specimens of wild and cultured, age-0, freshwater species: largemouth bass Micropterus salmoides, black crappies Pomoxis nigromaculatus, white crappies P. annularis, and black-nose crappies. Four fatty acids were investigated: linoleic acid (18:2n-6), linolenic acid (18:3n-3), arachidonic acid (20:4n-6), and docosahexaenoic acid (22:6n-3). Linoleic acid was the primary fatty acid used to differentiate juvenile wild from cultured fishes. Concentrations of linoleic acid were significantly different (p < 0.05) in cultured largemouth bass and black crappies from the wild counterparts. Linolenic acid concentrations were not significantly different (p < 0.05) between wild and cultured largemouth bass but were significantly different between wild and cultured black crappies. Wild largemouth bass contained higher concentrations of arachidonic acid than the cultured bass, and concentrations of docosahexaenoic acid were twice as high in wild black crappies than cultured black crappies. On the basis of four signature fatty acids, 90 of 91 juvenile fishes were correctly classified as wild or cultured; 32 of 37 wild juvenile fishes originating from the same reservoir were differentiated by species. Data from the training set were used to classify a test set of fishes as to species, source, or origin with 100% accuracy. PMID:15969511

  12. Effects of the Headspace Gas Composition on Anaerobic Biotransformation of o-, m-, and p-Toluic Acid in Sediment Slurries

    Microsoft Academic Search

    Shiu-Mei Liu; Wei-Chiung Chi

    2003-01-01

    Composition of the headspace gas affected the biotransformation pattern of toluic acid isomers in anoxic sediment slurries. Under an N2 atmosphere, o- and m-, and p-toluic acid (20–25 mg L) were biotransformed in 100 days, 77 days, and 148 days, respectively, with a lag period of 50 days, 49 days, and 50 days, respectively. Under a CO2 atmosphere, the same toluic acid

  13. Nutritional Evaluation of Seasonal Changes in Muscle Fatty Acid Composition of Common Carp (Cyprinus carpio) in Karamik Lake, Turkey

    Microsoft Academic Search

    Sait Bulut; Kazim Uysal; Mustafa Cemek; Veli Gok; S. Feyza Ku?; Mehmet Karaçal?

    2012-01-01

    The present study aims to determine seasonal changes of nutritional value of common carp in Karam?k Lake by determining the fatty acid composition. The levels of saturated, monounsaturated, and polyunsaturated fatty acids in 100 g total fatty acid were found to be 28.73, 25.31, and 38.19 g in winter; 29.39, 24.06, and 35.75 g in spring; 31.05, 35.02, and 24.86

  14. Influence of Hygrothermal Ageing on the Physico-Mechanical Properties of Alkali Treated Industrial Hemp Fibre Reinforced Polylactic Acid Composites

    Microsoft Academic Search

    M. S. Islam; K. L. Pickering; N. J. Foreman

    2010-01-01

    30 wt% aligned untreated long hemp fibre\\/polylactic acid (AUL) and aligned alkali treated long hemp fibre\\/polylactic acid\\u000a (AAL) composites were produced by film stacking and subjected to hygrothermal ageing environment along with neat polylactic\\u000a acid (PLA). Hygrothermal ageing was carried out by immersing samples in distilled water at 25 and 50 °C over a period of 3 months.\\u000a It was found that both

  15. Fatty acid and cholesterol composition of camel’s ( Camelus bactrianus, Camelus dromedarius and hybrids) milk in Kazakhstan

    Microsoft Academic Search

    Gaukhar Konuspayeva; Émilie Lemarie; Bernard Faye; Gérard Loiseau; Didier Montet

    2008-01-01

    The fatty acid composition and cholesterol content of 22 camel’s milk samples from different regions of Kazakhstan were determined,\\u000a in different seasons and with different camel species (Bactrian, dromedary and hybrids). Camel milk fat differed from mammalian\\u000a fats by its high content of the long-chain fatty acids C14:0, C16:0, C18:0 and C18:l. Great differences in fatty acid composition\\u000a occurred between

  16. Molecular composition of dicarboxylic acids, ketocarboxylic acids, ?-dicarbonyls and fatty acids in atmospheric aerosols from Tanzania, East Africa during wet and dry seasons

    NASA Astrophysics Data System (ADS)

    Mkoma, S. L.; Kawamura, K.

    2013-02-01

    Atmospheric aerosol samples of PM2.5 and PM10 were collected during the wet and dry seasons in 2011 from a rural site in Tanzania and analysed for water-soluble dicarboxylic acids, ketocarboxylic acids, ?-dicarbonyls, and fatty acids using a gas chromatography/flame ionization detector (GC/FID) and GC/mass spectrometry. Here we report the molecular composition and sources of diacids and related compounds for wet and dry seasons. Oxalic acid (C2) was found as the most abundant diacid species followed by succinic and/or malonic acids whereas glyoxylic acid and glyoxal were the dominant ketoacid and ?-dicarbonyl, respectively in both seasons in PM2.5 and PM10. Mean concentration of C2 in PM2.5 (121 ± 47 ng m-3) was lower in wet season than dry season (258 ± 69 ng m-3). Similarly, PM10 samples showed lower concentration of C2 (169 ± 42 ng m-3) in wet season than dry season (292 ± 165 ng m-3). Relative abundances of C2 in total diacids were 65% and 67% in PM2.5 and 65% and 64% in PM10 in the wet and dry seasons, respectively. Total concentrations of diacids (289-362 ng m-3), ketoacids (37.8-53.7 ng m-3), and ?-dicarbonyls (5.7-7.8 ng m-3) in Tanzania are higher than those reported at a rural background site in Nylsvley (South Africa) but comparable or lower than those reported from sites in Asia and Europe. Diacids and ketoacids were found to be present mainly in PM2.5 in both seasons (total ?-dicarbonyls in the dry season), suggesting a production of organic acids from pyrogenic sources and photochemical oxidations. Averaged contributions of total diacids to aerosol total carbon were 1.4% in PM2.5 and 2.1% in PM10 during wet season and 3.3% in PM2.5 and 3.9% in PM10 during dry season whereas those to water-soluble organic carbon were 2.2% and 4.7% in PM2.5 during wet season and 3.1% and 5.8% in PM10 during dry season. The higher ratios in dry season suggest an enhanced photochemical oxidation of organic precursors probably via heterogeneous reactions on aerosols under strong solar radiation. Strong positive correlations were found among diacids and related compounds as well as good relations to source tracers in both seasons, suggesting a mixed source from natural biogenic emissions, biomass burning, biofuel combustion, and photochemical production.

  17. Predicting beef cuts composition, fatty acids and meat quality characteristics by spiral computed tomography.

    PubMed

    Prieto, N; Navajas, E A; Richardson, R I; Ross, D W; Hyslop, J J; Simm, G; Roehe, R

    2010-11-01

    The potential of X-ray computed tomography (CT) as a predictor of cuts composition and meat quality traits using a multivariate calibration method (partial least square regression, PLSR) was investigated in beef cattle. Sirloins from 88 crossbred Aberdeen Angus (AAx) and 106 Limousin (LIMx) cattle were scanned using spiral CT. Subsequently, they were dissected and analyzed for technological and sensory parameters, as well as for intramuscular fat (IMF) content and fatty acid composition. CT-PLSR calibrations, tested by cross-validation, were able to predict with high accuracy the subcutaneous fat (R2, RMSECV=0.94, 34.60 g and 0.92, 34.46 g), intermuscular fat (R2, RMSECV=0.81, 161.54 g and 0.86, 42.16 g), total fat (R2, RMSECV=0.89, 65.96 g and 0.93, 48.35 g) and muscle content (R2, RMSECV=0.99, 58.55 g and 0.97, 57.45 g) in AAx and LIMx samples, respectively. Accurate CT predictions were found for fatty acid profile (R2=0.61-0.75) and intramuscular fat content (R2=0.71-0.76) in both sire breeds. However, low to very low accuracies were obtained for technological and sensory traits with R2 ranged from 0.01 to 0.26. The image analysis evaluated provides the basis for an alternative approach to deliver very accurate predictions of cuts composition, IMF content and fatty acid profile with lower costs than the reference methods (dissection, chemical analysis), without damaging or depreciating the beef cuts. PMID:20655149

  18. Composition effects of FePt alloy nanoparticles on the electro-oxidation of formic acid.

    PubMed

    Chen, Wei; Kim, Jaemin; Sun, Shouheng; Chen, Shaowei

    2007-10-23

    The catalytic activities of FexPt100-x alloy nanoparticles at different compositions (x=10, 15, 42, 54, 58, and 63) in the electro-oxidation of formic acid have been investigated by using cyclic voltammetry (CV), chronoamperometry, and electrochemical impedance spectroscopy (EIS). It was observed that the electrocatalytic performance was strongly dependent on the FePt particle composition. In chronoamperometric measurements, the alloy particles at x approximately 50 showed the highest steady-state current density among the catalysts under study and maintained the best long-term stability. In addition, on the basis of the anodic peak current density, onset potentials, and the ratios of the anodic peak current density to the cathodic peak current density in CV studies, the catalytic activity for HCOOH oxidation was found to decrease in the order of Fe42Pt58>Fe54Pt46 approximately Fe58Pt42>Fe15Pt85>Fe10Pt90>Fe63Pt37. That is, within the present experimental context, the alloy nanoparticles at x approximately 50 appeared to exhibit the maximum electrocatalytic activity and stability with optimal tolerance to CO poisoning. Consistent responses were also observed in electrochemical impedance spectroscopic measurements. For the alloy nanoparticles that showed excellent tolerance to CO poisoning, the impedance in the Nyquist plots was found to change sign from positive to negative with increasing electrode potential, suggesting that the electron-transfer kinetics evolved from resistive to pseudoinductive and then to inductive characters. However, for the nanoparticles that were heavily poisoned by adsorbed CO species during formic acid oxidation, the impedance was found to be confined to the first quadrant at all electrode potentials. The present work highlights the influence of the molecular composition of Pt-based alloy electrocatalysts on the performance of formic acid electro-oxidation, an important aspect in the design of bimetal electrocatalysts in fuel cell applications. PMID:17892313

  19. Chemical taxonomy of the hinge-ligament proteins of bivalves according to their amino acid compositions.

    PubMed Central

    Kikuchi, Y; Tamiya, N

    1987-01-01

    The proteins in the hinge ligaments of molluscan bivalves were subjected to chemotaxonomic studies according to their amino acid compositions. The hinge-ligament protein is a new class of structure proteins, and this is the first attempt to introduce chemical taxonomy into the systematics of bivalves. The hinge-ligament proteins from morphologically close species, namely mactra (superfamily Mactracea) or scallop (family Pectinidae) species, showed high intraspecific homology in their compositions. On the other hand, inconsistent results were obtained with two types of ligament proteins in pearl oyster species (genus Pinctada). The results of our chemotaxonomic analyses were sometimes in good agreement with the morphological classifications and sometimes inconsistent, implying a complicated phylogenetic relationship among the species. PMID:3593265

  20. Chemical taxonomy of the hinge-ligament proteins of bivalves according to their amino acid compositions.

    PubMed

    Kikuchi, Y; Tamiya, N

    1987-03-01

    The proteins in the hinge ligaments of molluscan bivalves were subjected to chemotaxonomic studies according to their amino acid compositions. The hinge-ligament protein is a new class of structure proteins, and this is the first attempt to introduce chemical taxonomy into the systematics of bivalves. The hinge-ligament proteins from morphologically close species, namely mactra (superfamily Mactracea) or scallop (family Pectinidae) species, showed high intraspecific homology in their compositions. On the other hand, inconsistent results were obtained with two types of ligament proteins in pearl oyster species (genus Pinctada). The results of our chemotaxonomic analyses were sometimes in good agreement with the morphological classifications and sometimes inconsistent, implying a complicated phylogenetic relationship among the species. PMID:3593265

  1. Low pressure process for continuous fiber reinforced polyamic acid resin matrix composite laminates

    NASA Technical Reports Server (NTRS)

    Druyun, Darleen A. (inventor); Hou, Tan-Hung (inventor); Kidder, Paul W. (inventor); Reddy, Rakasi M. (inventor); Baucom, Robert M. (inventor)

    1994-01-01

    A low pressure processor was developed for preparing a well-consolidated polyimide composite laminate. Prepreg plies were formed from unidirectional fibers and a polyamic acid resin solution. Molding stops were placed at the sides of a matched metal die mold. The prepreg plies were cut shorter than the length of the mold in the in-plane lateral direction and were stacked between the molding stops to a height which was higher than the molding stops. The plies were then compressed to the height of the stops and heated to allow the volatiles to escape and to start the imidization reaction. After removing the stops from the mold, the heat was increased and 0 - 500 psi was applied to complete the imidization reaction. The heat and pressure were further increased to form a consolidated polyimide composite laminate.

  2. Activation of the Jasmonic Acid Plant Defence Pathway Alters the Composition of Rhizosphere Bacterial Communities

    PubMed Central

    Carvalhais, Lilia C.; Dennis, Paul G.; Badri, Dayakar V.; Tyson, Gene W.; Vivanco, Jorge M.; Schenk, Peer M.

    2013-01-01

    Jasmonic acid (JA) signalling plays a central role in plant defences against necrotrophic pathogens and herbivorous insects, which afflict both roots and shoots. This pathway is also activated following the interaction with beneficial microbes that may lead to induced systemic resistance. Activation of the JA signalling pathway via application of methyl jasmonate (MeJA) alters the composition of carbon containing compounds released by roots, which are implicated as key determinants of rhizosphere microbial community structure. In this study, we investigated the influence of the JA defence signalling pathway activation in Arabidopsis thaliana on the structure of associated rhizosphere bacterial communities using 16S rRNA gene amplicon pyrosequencing. Application of MeJA did not directly influence bulk soil microbial communities but significant changes in rhizosphere community composition were observed upon activation of the jasmonate signalling pathway. Our results suggest that JA signalling may mediate plant-bacteria interactions in the soil upon necrotrophic pathogen and herbivorous insect attacks. PMID:23424661

  3. Preparation and characterization of aligned carbon nanotubes/polylactic acid composite fibers

    NASA Astrophysics Data System (ADS)

    Kong, Yuxia; Yuan, Jie; Qiu, Jun

    2012-07-01

    Aligned functionalized multiwalled carbon nanotubes/polylactic acid (MWNTs-PCL/PLA) composite fibers were successfully prepared by electrospinning processing. The MWNTs bonded with the polycaprolactone chains exhibited excellent uniform dispersion in PLA solution by comparing with the acid-functionalized MWNTs and amino-functionalized MWNTs. Optical microscopy was used to study the aligned degree of the fibers and to investigate the influences of the electrodes distance on the alignment and structure of the fibers, and results showed that the best quality of aligned fibers with dense structure and high aligned degree were obtained at an electrodes distance of 3 cm. Moreover, the MWNTs embedded inside the MWNTs-PCL/PLA fibers displayed well orientation along the axes of the fibers, which was demonstrated by field emission scanning electron microscopy, transmission electron microscopy and Raman spectroscopy.

  4. Correlated Strontium and Barium Isotopic Compositions of Acid-Cleaned Single Silicon Carbides from Murchison

    E-print Network

    Liu, Nan; Gallino, Roberto; Davis, Andrew M; Bisterzo, Sara; Gyngard, Frank; Kaeppeler, Franz; Cristallo, Sergio; Dauphas, Nicolas; Pellin, Michael J; Dillmann, Iris

    2015-01-01

    We present strontium, barium, carbon, and silicon isotopic compositions of 61 acid-cleaned presolar SiC grains from Murchison. Comparison with previous data shows that acid washing is highly effective in removing both strontium and barium contamination. For the first time, by using correlated $^{88}Sr$/$^{86}Sr$ and $^{138}Ba$/$^{136}Ba$ ratios in mainstream SiC grains, we are able to resolve the effect of $^{13}C$ concentration from that of $^{13}C$-pocket mass on s-process nucleosynthesis, which points towards the existence of large $^{13}C$-pockets with low $^{13}C$ concentration in AGB stars. The presence of such large $^{13}$R-pockets with a variety of relatively low $^{13}C$ concentrations seems to require multiple mixing processes in parent AGB stars of mainstream SiC grains.

  5. Characterization of fatty acid composition in healthy and bleached corals from Okinawa, Japan

    NASA Astrophysics Data System (ADS)

    Bachok, Zainudin; Mfilinge, Prosper; Tsuchiya, Makoto

    2006-11-01

    Under bleaching conditions, corals lose their symbiotic zooxanthellae, and thus, the ability to synthesize fatty acids (FAs) from photosynthetically derived carbon. This study investigated the lipid content and FA composition in healthy and bleached corals from the Odo reef flat in Okinawa, southern Japan, following a bleaching event. It was hypothesized that the FA composition and abundance would change as algae are lost or die, and possibly microbial abundance would increase in corals as a consequence of bleaching. The lipid content and FA composition of three healthy coral species ( Pavona frondifera, Acropora pulchra, and Goniastrea aspera) and of partially bleached and completely bleached colonies of P. frondifera were examined. The FA composition did not differ among healthy corals, but differed significantly among healthy, partially bleached, and completely bleached specimens of P. frondifera. Completely bleached corals contained significantly lower lipid and total FA content, as well as lower relative amounts of polyunsaturated FAs and higher relative amounts of saturated FAs, than healthy and partially bleached corals. Furthermore, there was a significantly higher relative concentration of monounsaturated FAs and odd-numbered branched FAs in completely bleached corals, indicating an increase in bacterial colonization in the bleached corals.

  6. Preparation and characterization of a composite hydrogel with graphene oxide as an acid catalyst.

    PubMed

    Jiang, Ting; Sui, Zhu-Yin; Yang, Quan-Sheng; Zhang, Xuetong; Han, Bao-Hang

    2015-04-28

    In this study, a facile method for synthesizing a novel graphene oxide/pyrrole-formaldehyde (GOP-1) composite hydrogel was developed via in situ polymerization of pyrrole and formaldehyde in the presence of graphene oxide sheets without any additional catalyst. During the polymerization, graphene oxide can act as a two-dimensional template to regulate the aggregation state of polymer and as an acid catalyst to accelerate the reaction rate of pyrrole and formaldehyde. The morphology and microstructure were investigated by scanning electron microscopy, transmission electron microscopy, and X-ray diffraction, respectively. The chemical properties were analyzed via X-ray photoelectron spectroscopy, infrared spectroscopy, and Raman spectroscopy. The freeze-dried GOP-1 composite hydrogel exhibited a large specific surface area, high nitrogen content, and three-dimensional network structure. Based on the above features, the freeze-dried GOP-1 composite hydrogel used as a gas adsorbent showed a high carbon dioxide uptake capacity at 1.0 bar and 273 K (11.1 wt%), in sharp contrast to that of graphene oxide (7.4 wt%). Furthermore, the as-prepared composite hydrogel may possess attractive potential in the fields of electrode material, tissue engineering, and water treatment. PMID:25760407

  7. The isolation and amino acid composition of Cathepsins B and B' 

    E-print Network

    Moeller, Patrick Wayne

    1970-01-01

    , 1970 Fgajor Subject: Food Technology THF. ISOLATION AND AMINO ACID COMPOSITION OF CATHEPSI'NS B AND B' A Thesis by PATRICK WAYNF. MOELLER Approved as to sty1e and content by: / . j~, . 6~1'(4 Q~-"-t' r- (Chairman of Committee) !Head...-75 in the same buffer system. The structure of these enzymes was investigated with disc gel electrophoresis. Urea was used to attempt to separate any aggregates held together by hydrogen bondi, ng. The enzymes showed no breakdown into subunits...

  8. Unusual fatty acid composition of cerebrosides from the filamentous soil fungus Mortierella alpina

    Microsoft Academic Search

    S. G Batrakov; I. V Konova; V. I Sheichenko; S. E Esipov; L. A Galanina; L. N Istratova

    2002-01-01

    The cerebrosides produced by the soil filamentous fungus Mortierella alpina strain KG-1\\/95 account for about 13% of the total polar lipids extractable from lyophilised cells with chloroform\\/methanol mixtures. By means of 1H NMR and 13C NMR spectroscopy, matrix-assisted laser-desorption ionisation mass spectrometry, and chemical degradation experiment, they have been shown to be 1-O-?-d-glucopyranosyl-2-N-(2?-d-hydroxyalkanoyl)-9-methylsphinga-4(E),8(E)-dienines, the fatty acid composition of which is

  9. Poly(vinyl alcohol-co-lactic acid)\\/Hydroxyapatite Composites: Synthesis and Characterization

    Microsoft Academic Search

    Nita TudorachiAurica; Aurica P. Chiriac

    2011-01-01

    There is a wide range of applications where calcium phosphate and hydroxyapatite (HA) are used as biomaterials, e.g. as synthetic\\u000a bone grafts, coating on metal prostheses (like hip endoprostheses or dental implants) and drug carriers. In the study, the\\u000a design and synthesis of composites based on poly(vinyl alcohol-co-lactic acid)\\/hydroxyapatite (PVA-co-LA\\/HA) with potential\\u000a for biomedical applications, they are presented. The hydroxyapatite

  10. Effect of acid and TETA modification on mechanical properties of MWCNTs\\/epoxy composites

    Microsoft Academic Search

    Shuqin Li; Fang Wang; Ye Wang; Jingwen Wang; Jun Ma; Jun Xiao

    2008-01-01

    Acid treatment and triethylene-tetramine (TETA) modification of multi-walled carbon nanotubes (MWCNTs) purposing to attain\\u000a better dispersibility and stronger interfacial bonding between MWCNTs and epoxy matrix have been carried out in this paper.\\u000a The epoxy and MWCNTs\\/epoxy composites were produced by cast molding method. Stress–strain curves show that TETA-MWCNTs\\/epoxy\\u000a hold the greatest toughness of all samples with 0.5 wt.% nanoparticles. The Young’s

  11. Evaluation of microwave acid digestion for determination of fiber-volume contents in carbon-epoxy composites

    SciTech Connect

    Siegel, M.C.; McLaughlin, V.N.; El-Amin, L.; Ilias, S. [North Carolina A and T State Univ., Greensboro, NC (United States)

    1995-06-01

    The analysis of carbon-epoxy composites for fiber-volume contents is significant in determining the quality and strength of a given composite. The method commonly being used is acid digestion in a hot water bath, which takes about 2.5 hours for digestion alone. A study has been done using a new technique, what is known as Microwave Acid Digestion (MAD) for quick determination of fiber-volume contents of carbon-epoxy composites. This technique uses a specially designed teflon bomb for digestion. The bomb allows for temperatures up to 250 C and pressures up to 1,200 psi. Under such operating conditions, the MAD technique reduces digestion time to about 70 seconds. The study demonstrated that the microwave acid digestion (MAD) is an efficient means for determination of fiber-volume contents of carbon-epoxy composites.

  12. Predicting G-protein-coupled receptors families using different physiochemical properties and pseudo amino acid composition.

    PubMed

    Rehman, Zia-Ur; Mirza, Muhammad Tayyeb; Khan, Asifullah; Xhaard, Henri

    2013-01-01

    G-protein-coupled receptors (GPCRs) initiate signaling pathways via trimetric guanine nucleotide-binding proteins. GPCRs are classified based on their ligand-binding properties and molecular phylogenetic analyses. Nonetheless, these later analyses are in most case dependent on multiple sequence alignments, themselves dependent on human intervention and expertise. Alignment-free classifications of GPCR sequences, in addition to being unbiased, present many applications uncovering hidden physicochemical parameters shared among specific groups of receptors, to being used in automated workflows for large-scale molecular modeling applications. Current alignment-free classification methods, however, do not reach a full accuracy. This chapter discusses how GPCRs amino acid sequences can be classified using pseudo amino acid composition and multiscale energy representation of different physiochemical properties of amino acids. A hybrid feature extraction strategy is shown to be suitable to represent GPCRs and to be able to exploit GPCR amino acid sequence discrimination capability in spatial as well as transform domain. Classification strategies such as support vector machine and probabilistic neural network are then discussed in regards to GPCRs classification. The work of GPCR-Hybrid web predictor is also discussed. PMID:23374180

  13. Oxygen Consumption Constrains Food Intake in Fish Fed Diets Varying in Essential Amino Acid Composition

    PubMed Central

    Saravanan, Subramanian; Geurden, Inge; Figueiredo-Silva, A. Cláudia; Nusantoro, Suluh; Kaushik, Sadasivam; Verreth, Johan; Schrama, Johan W.

    2013-01-01

    Compromisation of food intake when confronted with diets deficient in essential amino acids is a common response of fish and other animals, but the underlying physiological factors are poorly understood. We hypothesize that oxygen consumption of fish is a possible physiological factor constraining food intake. To verify, we assessed the food intake and oxygen consumption of rainbow trout fed to satiation with diets which differed in essential amino acid (methionine and lysine) compositions: a balanced vs. an imbalanced amino acid diet. Both diets were tested at two water oxygen levels: hypoxia vs. normoxia. Trout consumed 29% less food under hypoxia compared to normoxia (p<0.001). Under both hypoxia and normoxia trout significantly reduced food intake by 11% and 16% respectively when fed the imbalanced compared to the balanced amino acid diet. Oxygen consumption of the trout per unit body mass remained identical for both diet groups not only under hypoxia but also under normoxia (p>0.05). This difference in food intake between diets under normoxia together with the identical oxygen consumption supports the hypothesis that food intake in fish can be constrained by a set-point value of oxygen consumption, as seen here on a six-week time scale. PMID:23991148

  14. Influence of the composition of monoacyl phosphatidylcholine based microemulsions on the dermal delivery of flufenamic acid.

    PubMed

    Hoppel, Magdalena; Ettl, Hanna; Holper, Evelyn; Valenta, Claudia

    2014-11-20

    Although microemulsions are one of the most promising dermal carrier systems, their clinical use is limited due to their skin irritation potential. Therefore, microemulsions based on naturally derived monoacyl phosphatidylcholine (MAPL) were developed. The influence of the water, oil and surfactant content on dermal delivery of flufenamic acid was systematically investigated for the first time. A water-rich microemulsion led to significantly higher in vitro skin penetration of flufenamic acid compared to other microemulsions. The superiority of the water-rich microemulsion over a marketed flufenamic acid containing formulation was additionally confirmed. Differences in drug delivery could be explained by alterations of the microemulsions after application. Evaporation of isopropanol led to crystal-like structures of MAPL on the skin surface from the surfactant- or oleic acid-rich microemulsions. In contrast, the formation of this additional barrier was hindered in case of the water-rich microemulsion. The skin penetration of MAPL was additionally analyzed by combined ATR-FTIR and tape stripping experiments, where MAPL itself penetrated only into the initial layers of the stratum corneum, independent of the microemulsion composition. Since a surfactant must penetrate the skin to cause irritation, MAPL can be presumed as a skin-friendly emulsifier with the ability to stabilize pharmaceutically acceptable microemulsions. PMID:25178824

  15. Effective amino acid composition of seaweeds inducing food preference behaviors in Aplysia kurodai.

    PubMed

    Nagahama, Tatsumi; Fujimoto, Kiyo; Takami, Shigemi; Kinugawa, Aiko; Narusuye, Kenji

    2009-07-01

    Aplysia kurodai feeds on Ulva but rejects Gelidium and Pachydictyon with distinct patterned jaw movements. We previously demonstrated that these movements are induced by taste alone. Thus some chemicals may contribute to induction of these responses. We explored the amino acids composition of Ulva, Gelidium and Pachydictyon extracts used during our taste-induced physiological experiments. These solutions contained many constituents. The concentrations of six amino acids (Asp, Asn, Glu, Gln, Phe, Tau) were obviously different in the three extract solutions. We explored patterned jaw movements following application of solutions containing a pure amino acid. We statistically compared the occurrence numbers of ingestion-like and rejection-like patterned jaw movements (positive and negative values, respectively) for each amino acid. Our results suggested that L-Asn tends to induce ingestion-like responses, likely resulting in a preference of Ulva. In contrast, L-Asp tends to induce rejection-like responses, likely resulting in aversion towards Pachydictyon. In addition, we demonstrated that L-Asn and L-Asp solutions were sufficient to induce muscle activity associated with ingestion-like or rejection-like responses in the jaw muscles of a semi-intact preparation. PMID:19447292

  16. Changes of amino acid composition and lysinoalanine formation in alkali-pickled duck eggs.

    PubMed

    Chang, H M; Tsai, C F; Li, C F

    1999-04-01

    Duck eggs were pickled in alkali for 20 days to prepare Pidan. The extent of the degradation of compositional amino acids, the formation of lysinoalanine (LAL) in Pidan, and the relationship between the formation of LAL and the racemization values of D-serine and D-aspartic acid in Pidan albumen during the pickling period were investigated. Results showed that the remaining percentages of Cys, Arg, Lys, Ser, and Thr in albumen were much lower than that of the corresponding amino acid in yolk. The formation of LAL in albumen in the first stage was due to the speedy increase in the pH and the abundant formation of dehydroalanine (DHA) from cysteine. However, the formation of LAL in the later pickling period was related much more to the alkali-treating time than to the pH factor. Among the amino acids, cysteine was observed to be the most sensitive to alkaline and contributed mostly to the formation of LAL throughout the pickling period. PMID:10564005

  17. Novel composite material polyoxovanadate@MIL-101(Cr): a highly efficient electrocatalyst for ascorbic acid oxidation.

    PubMed

    Fernandes, Diana M; Barbosa, André D S; Pires, João; Balula, Salete S; Cunha-Silva, Luís; Freire, Cristina

    2013-12-26

    A novel hybrid composite material, PMo10V2@MIL-101 was prepared by the encapsulation of the tetra-butylammonium (TBA) salt of the vanadium-substituted phosphomolybdate [PMo10V2O40](5-) (PMo10V2) into the porous metal-organic framework (MOF) MIL-101(Cr). The materials characterization by powder X-ray diffraction, Fourier transform infrared spectra and scanning electron microscopy confirmed the preparation of the composite material without disruption of the MOF porous structure. Pyrolytic graphite electrodes modified with the original components (MIL-101(Cr), PMo10V2), and the composite material PMo10V2@MIL-101 were prepared and their electrochemical responses were studied by cyclic voltammetry. Surface confined redox processes were observed for all the immobilized materials. MIL-101(Cr) showed one-electron reduction process due to chromium centers (Cr(III) ? Cr(II)), while PMo10V2 presented five reduction processes: the peak at more positive potentials is attributed to two superimposed 1-electron vanadium reduction processes (V(V) ? V(IV)) and the other four peaks to Mo-centred two-electron reduction processes (Mo(VI) ? Mo(V)). The electrochemical behavior of the composite material PMo10V2@MIL-101 showed both MIL-101(Cr) and PMo10V2 redox features, although with the splitting of the two vanadium processes and the shift of the Mo- and Cr- centered processes to more negative potentials. Finally, PMo10V2@MIL-101 modified electrode showed outstanding enhanced vanadium-based electrocatalytic properties towards ascorbic acid oxidation, in comparison with the free PMo10V2, as a result of its immobilization into the porous structure of the MOF. Furthermore, PMo10V2@MIL-101 modified electrode showed successful simultaneous detection of ascorbic acid and dopamine. PMID:24308331

  18. RNA Preservation Agents and Nucleic Acid Extraction Method Bias Perceived Bacterial Community Composition

    PubMed Central

    McCarthy, Ann; Chiang, Edna; Schmidt, Marian L.; Denef, Vincent J.

    2015-01-01

    Bias is a pervasive problem when characterizing microbial communities. An important source is the difference in lysis efficiencies of different populations, which vary depending on the extraction protocol used. To avoid such biases impacting comparisons between gene and transcript abundances in the environment, the use of one protocol that simultaneously extracts both types of nucleic acids from microbial community samples has gained popularity. However, knowledge regarding tradeoffs to combined nucleic acid extraction protocols is limited, particularly regarding yield and biases in the observed community composition. Here, we evaluated a commercially available protocol for simultaneous extraction of DNA and RNA, which we adapted for freshwater microbial community samples that were collected on filters. DNA and RNA yields were comparable to other commonly used, but independent DNA and RNA extraction protocols. RNA protection agents benefited RNA quality, but decreased DNA yields significantly. Choice of extraction protocol influenced the perceived bacterial community composition, with strong method-dependent biases observed for specific phyla such as the Verrucomicrobia. The combined DNA/RNA extraction protocol detected significantly higher levels of Verrucomicrobia than the other protocols, and those higher numbers were confirmed by microscopic analysis. Use of RNA protection agents as well as independent sequencing runs caused a significant shift in community composition as well, albeit smaller than the shift caused by using different extraction protocols. Despite methodological biases, sample origin was the strongest determinant of community composition. However, when the abundance of specific phylogenetic groups is of interest, researchers need to be aware of the biases their methods introduce. This is particularly relevant if different methods are used for DNA and RNA extraction, in addition to using RNA protection agents only for RNA samples. PMID:25798612

  19. The heparan and heparin metabolism pathway is involved in regulation of fatty acid composition.

    PubMed

    Jiang, Zhihua; Michal, Jennifer J; Wu, Xiao-Lin; Pan, Zengxiang; MacNeil, Michael D

    2011-01-01

    Six genes involved in the heparan sulfate and heparin metabolism pathway, DSEL (dermatan sulfate epimerase-like), EXTL1 (exostoses (multiple)-like 1), HS6ST1 (heparan sulfate 6-O-sulfotransferase 1), HS6ST3 (heparan sulfate 6-O-sulfotransferase 3), NDST3 (N-deacetylase/N-sulfotransferase (heparan glucosaminyl) 3), and SULT1A1 (sulfotransferase family, cytosolic, 1A, phenol-preferring, member 1), were investigated for their associations with muscle lipid composition using cattle as a model organism. Nineteen single nucleotide polymorphisms (SNPs)/multiple nucleotide length polymorphisms (MNLPs) were identified in five of these six genes. Six of these mutations were then genotyped on 246 Wagyu x Limousin F(2) animals, which were measured for 5 carcass, 6 eating quality and 8 fatty acid composition traits. Association analysis revealed that DSEL, EXTL1 and HS6ST1 significantly affected two stearoyl-CoA desaturase activity indices, the amount of conjugated linoleic acid (CLA), and the relative amount of saturated fatty acids (SFA) and monounsaturated fatty acids (MUFA) in skeletal muscle (P<0.05). In particular, HS6ST1 joined our previously reported SCD1 and UQCRC1 genes to form a three gene network for one of the stearoyl-CoA desaturase activity indices. These results provide evidence that genes involved in heparan sulfate and heparin metabolism are also involved in regulation of lipid metabolism in bovine muscle. Whether the SNPs affected heparan sulfate proteoglycan structure is unknown and warrants further investigation. PMID:21647334

  20. Effect of SCD and SREBP genotypes on fatty acid composition in adipose tissue of Japanese Black cattle herds.

    PubMed

    Ohsaki, Hideki; Tanaka, Atsuko; Hoashi, Shogo; Sasazaki, Shinji; Oyama, Kenji; Taniguchi, Masaaki; Mukai, Fumio; Mannen, Hideyuki

    2009-06-01

    Fatty acid composition of beef adipose tissue is one of important traits because high proportions of monounsaturated fatty acid are related to favorable beef flavor and tenderness. In this study, we investigated effects of genetic factors such as stearoyl-CoA desaturase (SCD) and sterol regulatory element binding protein (SREBP) on beef carcass traits including fatty acid composition using two cattle populations. Sire effect was significantly related to almost all traits except BMS, suggesting that the trait examined in this study is highly controlled by genetic factors. The effect of SCD genotype on fatty acid composition was detected remarkably in both cattle groups, especially on stearic and oleic acids. This result was consistent with our previous studies and suggests that SCD is associated with fatty acid composition. Unlike SCD genotyping, the effect of SREBP genotype was not identified in this study. Our results suggested that SCD genotype would contribute to improving beef quality in field populations. Further studies about the relationship among these factors will bring an insight into the molecular mechanism of fatty acid metabolism in cattle. PMID:20163629

  1. Microalgae for use in tropical aquaculture II: Effect of salinity on growth, gross chemical composition and fatty acid composition of three species of marine microalgae

    Microsoft Academic Search

    S. M. Renaud; D. L. Parry

    1994-01-01

    The influence of salinity on the growth, gross chemical composition and fatty acid composition of three species of marine microalgae,Isochrysis sp.,Nannochloropsis oculata andNitzschia (frustulum), was investigated. There was no significant change in growth rate ofIsochrysis sp. andN. (frustulum) over the experimental range of salinity (10–35 ppt), whileN. oculata had a significantly slower growth rate only at 35 ppt. The ash

  2. Synthesis of a conformationally constrained ?-amino acid building block.

    PubMed

    O'Reilly, Elaine; Pes, Lara; Ortin, Yannick; Müller-Bunz, Helge; Paradisi, Francesca

    2013-02-01

    Conformationally restricted amino acids are important components in peptidomimetics and drug design. Herein, we describe the synthesis of a novel, non-proteinogenic constrained delta amino acid containing a cyclobutane ring, cis-3(aminomethyl)cyclobutane carboxylic acid (ACCA). The synthesis of the target amino acid was achieved in seven steps, with the key reaction being a base induced intramolecular nucleophilic substitution. A small library of dipeptides was prepared through the coupling of ACCA with proteinogenic amino acids. PMID:22851051

  3. Interspecific variability of RAPD and fatty acid composition of some pomegranate cultivars ( Punica granatum L.) growing in Southern Anatolia Region in Turkey

    Microsoft Academic Search

    Sezai Ercisli; Guleray Agar; Emine Orhan; Nalan Yildirim; Yasemin Hizarci

    2007-01-01

    The interspecific variability of fatty acid (FA) composition and RAPD profiles was used to examine biochemical and genetic relationships among six pomegranate cultivars, which dominate pomegranate production in Southern Anatolia Region of Turkey. Fatty acid composition of pomegranate leaves was determined by using gas chromatography. Differences in the FA composition were found among cultivars. In particular, cv. kirli hanim had

  4. Importance de l'acide linolnique alimentaire sur la composition des membranes nerveu-ses, le contrle d'activits enzymatiques, l'amplitude de paramtres lectrophysio-

    E-print Network

    Paris-Sud XI, Université de

    Importance de l'acide linolénique alimentaire sur la composition des membranes nerveu- ses, le aux agressions, en particulier toxiques. Les acides gras alimentaires, et plus particulièrement les acides gras polyinsaturés, ont une influence directe sur la composition des membranes cérébrales, donc

  5. Isoleucine epimerization and amino acid composition in molecular-weight separations of Pleistocene Genyornis eggshell

    NASA Astrophysics Data System (ADS)

    Kaufman, Darrell S.; Miller, Gifford H.

    1995-07-01

    This study explores the geochronological utility and analytical reproducibility of separating the high-molecular-weight fraction (HMW) from eggshells of the extinct late Pleistocene ratite, Genyornis, using disposable, prepacked gel-filtration columns. The superior integrity of ratite eggshell for the retention of amino acids indicates that this biomineral is better suited for this type of investigation than previously studied molluscan shell. To evaluate the reproducibility of the gel-filtration technique, we analyzed triplicate subsamples of three eggshells of different ages. The reproducibility, based on the average intrashell variation (coefficient of variation; CV) in the extent of isoleucine epimerization (aIle/Ile) in the HMW (enriched in molecules ca. >10,000 MW) is 3%, well within the range appropriate for geochronological purposes. The average intrashell variation in the total amino acid concentration (?[aa]) of the HMW is 5%, somewhat better than for the total acid hydrolysate (TOTAL) of the same samples (7%). To evaluate the relation between molecular weight and the rate of isoleucine epimerization, three molecular-weight fractions were separated using gel filtration, plus the naturally hydrolyzed free fraction (FREE), for each of four fossil eggshells. AIle/Ile increases with decreasing molecular weight in all shells, with a ca. sixfold to ninefold difference in ratios between the HMW andFREE, and a ca. fivefold difference between the HMW andTOTAL. Although linear correlations between aIle/Ile measured in each molecular-weight fraction and in theTOTAL are all highly significant (r ? 0.951), the relation between the extent of epimerization in the HMW and in the TOTAL is best expressed as an exponential function (r = 0.951). This relation is consistent with the idea that, as the epimerization reaction approaches equilibrium in theTOTAL (ca. aIle/Ile > 1.1), its rate decreases beyond that of the HMW. The amino acid composition (relative percent of eight amino acids or combinations of amino acids) is more uniform in the HMW of the four samples compared to lower-molecular-weight fractions. The greater "compositional stability" of the HMW indicates that it contains a residuum of macromolecules that have not been affected by the diagenetically driven changes observed in lower-molecular-weight fractions.

  6. The role of lipid composition for insertion and stabilization of amino acids in membranes

    NASA Astrophysics Data System (ADS)

    Johansson, Anna C. V.; Lindahl, Erik

    2009-05-01

    While most membrane protein helices are clearly hydrophobic, recent experiments have indicated that it is possible to insert marginally hydrophobic helices into bilayers and have suggested apparent in vivo free energies of insertion for charged residues that are low, e.g., a few kcals for arginine. In contrast, a number of biophysical simulation studies have predicted that the bilayer interior is close to a pure hydrophobic environment with large penalties for hydrophilic amino acids—and yet the experimental scales do significantly better at predicting actual membrane proteins from sequence. Here, we have systematically studied the dependence of the free energy profiles on lipid properties, including tail length, saturation, headgroup hydrogen bond strength, and charge, both to see to whether the in vivo insertion can be explained in whole or part from lipid composition of the endoplasmic reticulum (ER) membranes, and if the solvation properties can help interpret how protein function depends on the lipids. We find that lipid charge is important to stabilize charged amino acids inside the bilayer (with implications, e.g., for ion channels), that thicker bilayers have higher solvation costs for hydrophilic side chains, and that headgroup hydrogen bond strength determines how adaptive the lipids are as a hydrophobic/hydrophilic solvent. None of the different free energy profiles are even close to the low apparent in vivo insertion cost, which suggests that regardless of the specific ER membrane composition the current experimental results cannot be explained by normal lipid-type variation.

  7. High-resolution food webs based on nitrogen isotopic composition of amino acids

    PubMed Central

    Chikaraishi, Yoshito; Steffan, Shawn A; Ogawa, Nanako O; Ishikawa, Naoto F; Sasaki, Yoko; Tsuchiya, Masashi; Ohkouchi, Naohiko

    2014-01-01

    Food webs are known to have myriad trophic links between resource and consumer species. While herbivores have well-understood trophic tendencies, the difficulties associated with characterizing the trophic positions of higher-order consumers have remained a major problem in food web ecology. To better understand trophic linkages in food webs, analysis of the stable nitrogen isotopic composition of amino acids has been introduced as a potential means of providing accurate trophic position estimates. In the present study, we employ this method to estimate the trophic positions of 200 free-roaming organisms, representing 39 species in coastal marine (a stony shore) and 38 species in terrestrial (a fruit farm) environments. Based on the trophic positions from the isotopic composition of amino acids, we are able to resolve the trophic structure of these complex food webs. Our approach reveals a high degree of trophic omnivory (i.e., noninteger trophic positions) among carnivorous species such as marine fish and terrestrial hornets.This information not only clarifies the trophic tendencies of species within their respective communities, but also suggests that trophic omnivory may be common in these webs. PMID:25360278

  8. Distinctive lipid composition of the copepod Limnocalanus macrurus with a high abundance of polyunsaturated fatty acids.

    PubMed

    Hiltunen, Minna; Strandberg, Ursula; Keinänen, Markku; Taipale, Sami; Kankaala, Paula

    2014-09-01

    We studied the copepod Limnocalanus macrurus for seasonal variation in the composition of fatty acids, wax esters and sterols in large boreal lakes, where it occurs as a glacial-relict. Vast wax ester reserves of Limnocalanus were accumulated in a period of only two months, and comprised mono- and polyunsaturated fatty acids (PUFA) and saturated fatty alcohols. In winter, the mobilization of wax esters was selective, and the proportion of long-chain polyunsaturated wax esters declined first. PUFA accounted for >50% of all fatty acids throughout the year reaching up to ca. 65% during late summer and fall. Long-chain PUFA 20:5n-3 and 22:6n-3 together comprised 17-40% of all fatty acids. The rarely reported C24 and C26 very-long-chain PUFA (VLC-PUFA) comprised 6.2 ± 3.4 % of all fatty acids in August and 2.1 ± 1.7% in September. The VLC-PUFA are presumably synthesized by Limnocalanus from shorter chain-length precursors because they were not found in the potential food sources. We hypothesize that these VLC-PUFA help Limnocalanus to maximize lipid reserves when food is abundant. Sterol content of Limnocalanus, consisting ca. 90% of cholesterol, did not show great seasonal variation. As a lipid-rich copepod with high abundance of PUFA, Limnocalanus is excellent quality food for fish. The VLC-PUFA were also detected in planktivorous fish, suggesting that these compounds can be used as a trophic marker indicating feeding on Limnocalanus. PMID:25092258

  9. Changes in lipid content, lipid class composition and fatty acid composition of developing eggs and unfed larvae of cod ( Gadus morhua )

    Microsoft Academic Search

    A. J. Fraser; J. C. Gamble; J. R. Sargent

    1988-01-01

    Changes in the lipid class and fatty acid composition of developing eggs and unfed larvae of cod (Gadus morhua L.) were studied with the objective of determining probable requirements of cod larvae for dietary lipid. The eggs were collected on 24 March 1985 from holding tanks containing cod which had been caught off the northwest coast of Scotland. Phosphatidylcholine (PC)

  10. Effects of sucking acidic candy on whole-mouth saliva composition.

    PubMed

    Jensdottir, T; Nauntofte, B; Buchwald, C; Bardow, A

    2005-01-01

    Limited information is available on the effects of sucking acidic candies on saliva composition and the protective role of saliva in this relation. Therefore the aim of this study was to determine salivary effects of sucking acidic candies in vivo in relation to individual variations in whole-saliva flow rate (WSFR) and buffer capacity (WSbeta). Ten healthy young males (24 +/- 2 years) sucked a rhubarb-flavoured acidic hard-boiled candy with tartaric acid available on the Danish market. The whole saliva was collected into a closed system, regarding CO2, at different times as follows: firstly, unstimulated saliva for 5 min (baseline), secondly stimulated saliva for 4 min upon sucking the candy, and finally post-stimulated saliva for 10 min. Saliva pH was determined on a blood gas analyser and WSbeta was estimated from the saliva bicarbonate concentration obtained by the analyser and by ionic balance calculation. The erosive potential of the candy in saliva was estimated from the saliva pH values and degree of saturation with respect to hydroxyapatite (DS(HAp)). The results showed that saliva pH dropped from 6.5 (baseline) down to 4.5 at the fourth minute of sucking the candy, and returned to pH 6.5 five minutes after stimulation (post-stimulated). DS(HAp) decreased upon sucking the candy and saliva from all subjects became undersaturated with respect to HAp. Significant positive correlations were obtained between pH and WSFR (r(s) = 0.47; p < 0.05) and between pH and WSbeta (r(s) = 0.65; p < 0.01). In relation to WSbeta we found that 70% of the buffer capacity originating from the bicarbonate buffer system upon sucking the candy was exerted as phase buffering. We conclude that sucking this type of acidic candies changes whole-mouth saliva composition so that it may have erosive potential and that high WSFR and WSbeta have protective effects against these salivary changes. PMID:16251790

  11. Effect of copper on performance, carcass characteristics, and muscle fatty acid composition of meat goat kids.

    PubMed

    Huang, Y L; Wang, Y; Spears, J W; Lin, X; Guo, C H

    2013-10-01

    An experiment was conducted to determine the effects of dietary Cu on performance, carcass characteristics, and muscle fatty acid composition in meat goats. Thirty five Jianyang Big-ear goat (JYB) kids (average BW 20.3 ± 0.6 kg and age 3 to 4 mo) were stratified by weight and randomly assigned to 1 of 7 experimental treatments (n = 5 goats per treatment). Treatments consisted of: 1) control (no supplemental Cu; 14.3 mg Cu/kg DM), 2) 20 mg supplemental Cu/kg DM, 3) 40 mg supplemental Cu/kg DM, 4) 80 mg supplemental Cu/kg DM, 5) 160 mg supplemental Cu/kg DM, 6) 320 mg supplemental Cu/kg DM, and 7) 640 mg supplemental Cu/kg DM. Copper was supplemented from CuSO4•5H2O (25.2% Cu). Goats were individually fed a concentrate-hay based diet for 96 d. Performance was not affected by Cu concentration. Liver Cu concentration was increased (P < 0.01) with Cu supplementation. Goats supplemented with 0 or 20 mg Cu/kg DM had lower (P < 0.01) liver Cu concentrations than the other treatments. Backfat depth (P < 0.01) and intramuscular fat (IMF) content (P < 0.01) were also increased with Cu supplementation. However, Cu-supplemented goats had lower (P = 0.04) longissimus muscle area (LMA) compared with control. Dietary Cu supplementation increased the percentage of C14:0 (P < 0.01), C20:4 (P < 0.01), and total polyunsaturated fatty acids (P = 0.03), decreased C18:1 trans (P = 0.04), and tended to decrease C18:0 (P = 0.08) in LM. Other fatty acids detected were not affected by dietary Cu supplementation (P > 0.10). These results indicate that JYB goats can tolerate up to 640 mg Cu/kg DM for 96 d without adverse effects on performance, but fat deposition and fatty acid composition in the body could be altered by Cu supplementation as low as 20 mg/kg of diet with high concentrate-hay. Copper supplementation increased backfat depth, IMF, and percentage of polyunsaturated fatty acids in LM and decreased LMA in the carcass of JYB goats. PMID:23893982

  12. Milk and Cheese Fatty Acid Composition in Sheep Fed Mediterranean Forages with Reference to Conjugated Linoleic Acid cis-9,trans-11

    Microsoft Academic Search

    M. Addis; A. Cabiddu; G. Pinna; M. Decandia; G. Piredda; A. Pirisi; G. Molle

    2005-01-01

    Two experiments were undertaken to evaluate the effect on milk and cheese fatty acid composition of feed- ing different fresh forages to dairy sheep both in winter (experiment 1, growing stage of the forages, early lac- tating ewes) and in spring (experiment 2, reproduction stage of the forages, midlactating ewes). Four forage species were compared: annual ryegrass (RY, Lolium rigidum

  13. Cesium Sorption from Concentrated Acidic Tank Wastes Using Ammonium Molybdophosphate-polyacrylonitrile Composite Sorbents

    SciTech Connect

    Todd, Terry Allen; Mann, Nicholas Robert; Tranter, Troy Joseph; Sebesta, F.; John, J.; Motl, A.,

    2002-10-01

    Ammonium molybdophosphate-polyacrylonitrile (AMP-PAN) composite sorbents have been evaluated for the removal of cesium from Idaho National Engineering and Environmental Laboratory (INEEL) concentrated acidic tank waste. Batch contacts were performed to qualitatively evaluate the effects of increased nitric acid, sodium and potassium. An equilibrium isotherm was generated with simulated concentrated tank waste solutions and fit to the Langmuir equation. Additional batch contact experiments were performed to determine if mercury, plutonium and americium would sorb onto AMP-PAN. Dynamic sorption was evaluated in column tests employing 1.5 cm3 columns operating at 5, 10 and 20 bed volumes of flow per hour. Results indicate, as expected, that dynamic cesium sorption capacity is reduced as the flowrate is increased. Calculated dynamic capacities for cesium were 22.5, 19.8 and 19.6 mg Cs/g sorbent, for 5, 10 and 20 bed volume per hour flows, respectively. The thermal stability of loaded AMP-PAN was evaluated by performing thermogrovimetric analysis (TGA) on samples of AMP, PAN (polymer), and AMP-PAN. Results indicate that AMP-PAN is stable to 400 °C, with less than a 10% loss of weight, which is at least partially due to loss of water of hydration. The evaluation of AMP-PAN indicates that it will effectively remove cesium from concentrated acidic tank waste solutions.

  14. Predicting the fatty acid composition of milk: a comparison of two Fourier transform infrared sampling techniques.

    PubMed

    Afseth, Nils Kristian; Martens, Harald; Randby, Ashild; Gidskehaug, Lars; Narum, Bjørg; Jørgensen, Kjetil; Lien, Sigbjørn; Kohler, Achim

    2010-07-01

    In the present study a novel approach for Fourier transform infrared (FT-IR) characterization of the fatty acid composition of milk based on dried film measurements has been presented and compared to a standard FT-IR approach based on liquid milk measurements. Two hundred and sixty-two (262) milk samples were obtained from a feeding experiment, and the samples were measured with FT-IR as dried films as well as liquid samples. Calibrations against the most abundant fatty acids, CLA (i.e., 18:2cis-9, trans-11), 18:3cis-9, cis-12, cis-15, and summed fatty acid parameters were obtained for both approaches. The estimation errors obtained in the dried film calibrations were overall lower than the corresponding liquid sample calibrations. Similar and good calibrations (i.e., R(2) ranges from 0.82 to 0.94 (liquid samples) and from 0.88 to 0.97 (dried films)) for short-chain fatty acids (6:0-14:0), 18:1cis-9, SAT, MUFA, and iodine value were obtained by both approaches. However, the dried film approach was the only approach for which feasible calibrations (i.e., R(2) ranges from 0.78 to 0.93) were obtained for the major saturated fatty acids 16:0 and 18:0, the minor fatty acid features 4:0, CLA (i.e., 18:2cis-9, trans-11), PUFA, and the summed 18:1 trans isomers. For the dried film approach, logical spectral features were found to dominate the respective fatty acid calibration models. The preconcentration step of the dried film approach could be expected to account for a major part of the prediction improvements going from predictions in liquid milk to predictions in dried films. The dried film approach has a significant potential for use in high-throughput applications in industrial environments and might also serve as a valuable supplement for determination of genetic and breeding factors within research communities. PMID:20615281

  15. Surface Chirality of Gly-Pro Dipeptide Adsorbed on a Cu(110) Surface.

    PubMed

    Cruguel, Hervé; Méthivier, Christophe; Pradier, Claire-Marie; Humblot, Vincent

    2015-07-01

    The adsorption of chiral Gly-Pro dipeptide on Cu(110) has been characterized by combining in situ polarization modulation infrared reflection absorption spectroscopy (PM-RAIRS) and X-ray photoelectron spectroscopy (XPS). The chemical state of the dipeptide, and its anchoring points and adsorption geometry, were determined at various coverage values. Gly-Pro molecules are present on Cu(110) in their anionic form (NH2 /COO(-) ) and adsorb under a 3-point binding via both oxygen atoms of the carboxylate group and via the nitrogen atom of the amine group. Low-energy electron diffraction (LEED) and scanning tunneling microscopy (STM) have shown the presence of an extended 2D chiral array, sustained via intermolecular H-bonds interactions. Furthermore, due to the particular shape of the molecule, only one homochiral domain is formed, creating thus a truly chiral surface. Chirality 27:411-416, 2015. © 2015 Wiley Periodicals, Inc. PMID:25847844

  16. 157 nm Photodissociation of Dipeptide Ions Containing N-Terminal Arginine

    NASA Astrophysics Data System (ADS)

    Webber, Nathaniel; He, Yi; Reilly, James P.

    2013-12-01

    Twenty singly-charged dipeptide ions with N-terminal arginine were photodissociated using 157 nm light in both a linear ion-trap mass spectrometer and a MALDI-TOF-TOF mass spectrometer. Analogous to previous work on dipeptides containing C-terminal arginine, this set of samples enabled insights into the photofragmentation propensities associated with individual residues. In addition to familiar products such as a-, d-, and immonium ions, m2 and m2+13 ions were also observed. Certain side chains tended to cleave between their ? and ? carbons without necessarily forming d- or w-type ions, and a few other ions were produced by the high-energy fragmentation of multiple bonds.

  17. Microiontophoretic application of muramyl-dipeptide upon single cortical, hippocampal and hypothalamic neurons in rats.

    PubMed

    Dougherty, P M; Dafny, N

    1990-11-01

    Muramyl-dipeptide (MDP), a metabolite of bacterial cell walls, has a variety of biological effects, including the induction of acute phase serum glycoproteins and fever, and the promotion of slow wave sleep. Muramyl-dipeptide and other products, derived from immune responses, may act directly in the CNS to recruit secondary autonomic and endocrine responses to disease. To test this hypothesis the properties of single neuron discharges, following local application (microiontophoresis) of MDP within the somatosensory cortex, the dorsal hippocampus and the medial basal hypothalamus were studied in rats. The results obtained from cortical (N = 30), hippocampal (N = 28) and hypothalamic (N = 32) neurons demonstrated a direct effect of MDP upon all three regions of the brain. In addition, MDP modified the responses of these same neurons to morphine. These results support a role of MDP in the process of neuro-immune modulation and further demonstrate an interaction between lymphoid agents and opioids in the CNS. PMID:1982342

  18. Stable emulsions formed by self-assembly of interfacial networks of dipeptide derivatives.

    PubMed

    Bai, Shuo; Pappas, Charalampos; Debnath, Sisir; Frederix, Pim W J M; Leckie, Joy; Fleming, Scott; Ulijn, Rein V

    2014-07-22

    We demonstrate the use of dipeptide amphiphiles that, by hand shaking of a biphasic solvent system for a few seconds, form emulsions that remain stable for months through the formation of nanofibrous networks at the organic/aqueous interface. Unlike absorption of traditional surfactants, the interfacial networks form by self-assembly through ?-stacking interactions and hydrogen bonding. Altering the dipeptide sequence has a dramatic effect on the properties of the emulsions formed, illustrating the possibility of tuning emulsion properties by chemical design. The systems provide superior long-term stability toward temperature and salts compared to with sodium dodecyl sulfate (SDS) and can be enzymatically disassembled causing on-demand demulsification under mild conditions. The interfacial networks facilitate highly tunable and stable encapsulation and compartmentalization with potential applications in cosmetics, therapeutics, and food industry. PMID:24896538

  19. Multicomponent dipeptide hydrogels as extracellular matrix-mimetic scaffolds for cell culture applications

    PubMed Central

    Liyanage, Wathsala; Vats, Kanika; Rajbhandary, Annada; Benoit, Danielle S. W.

    2015-01-01

    Fmoc-3F-Phe-Arg-NH2 and Fmoc-3F-Phe-Asp-OH dipeptides undergo coassembly to form two-component nanofibril hydrogels. These hydrogels support the viability and growth of NIH 3T3 fibroblast cells. The supramolecular display of Arg and Asp at the nanofibril surface effectively mimics the integrin-binding RGD peptide of fibronectin, without covalent connection between the Arg and Asp functionality. PMID:26081605

  20. The Utilization of Dipeptides Containing L-Arginine by Chicken Macrophages

    Microsoft Academic Search

    C.-L. SU; R. E. AUSTIC

    L-Arginine is the precursor of NO, a cytotoxic agent of macrophages. Studies were carried out to determine whether dipeptides containing arginine can be utilized by lipopolysaccharide (LPS)-activated avian macrophages for NO production. A chicken macrophage cell line, the HD11 cell, was used in all experiments. Peptidase activities were observed in fetal bovine serum (FBS) and macrophage serum free medium (Mac-SFM).

  1. Profiling histidine dipeptides in plasma and urine after ingesting beef, chicken or chicken broth in humans

    Microsoft Academic Search

    Kyung-Jin Yeum; Marica Orioli; Luca Regazzoni; Marina Carini; Helen Rasmussen; Robert M. Russell; Giancarlo Aldini

    2010-01-01

    The in vitro metabolic stability of histidine-dipeptides (HD), carnosine (CAR) and anserine (ANS), in human serum, and their\\u000a absorption kinetics after ingesting pure carnosine or HD rich foods in humans have been investigated. Healthy women (n = 4) went through four phases of taking one dose of either 450 mg of pure carnosine, 150 g beef (B), 150 g chicken (C), or\\u000a chicken broth (CB)

  2. Carnosine, the anti-ageing, anti-oxidant dipeptide, may react with protein carbonyl groups

    Microsoft Academic Search

    Alan R Hipkiss; Carol Brownson; Martin J Carrier

    2001-01-01

    Carnosine (?-alanyl-l-histidine) is a physiological dipeptide which can delay ageing and rejuvenate senescent cultured human fibroblasts. Carnosine's anti-oxidant, free radical- and metal ion-scavenging activities cannot adequately explain these effects. Previous studies showed that carnosine reacts with small carbonyl compounds (aldehydes and ketones) and protects macromolecules against their cross-linking actions. Ageing is associated with accumulation of carbonyl groups on proteins. We

  3. The effect of the synthetic neuroprotective dipeptide noopept on glutamate release from rat brain cortex slices

    Microsoft Academic Search

    K. S. Us; P. M. Klodt; V. S. Kudrin; A. Ya. Sapronova; R. U. Ostrovskaya; M. V. Ugryumov; K. S. Rayevsky

    2007-01-01

    The level of spontaneous and K+-stimulated release of endogenous glutamate was studied in experiments on slices of brain cortex of Wistar rats. Pronounced\\u000a spontaneous release of the neuromediator and its increase under conditions of stimulation were registered by high-performance\\u000a liquid chromatography with electrochemical detection. The effect of the nootropic and neuroprotective dipeptide Noopept (GVS-111)\\u000a on release of glutamate was investigated.

  4. Novel nootropic dipeptide Noopept increases inhibitory synaptic transmission in CA1 pyramidal cells

    Microsoft Academic Search

    Rodion V. Kondratenko; Vladimir I. Derevyagin; Vladimir G. Skrebitsky

    2010-01-01

    Effects of newly synthesized nootropic and anxiolytic dipeptide Noopept on inhibitory synaptic transmission in hippocampal CA1 pyramidal cells were investigated using patch-clamp technique in whole-cell configuration. Bath application of Noopept (1?M) significantly increased the frequency of spike-dependant spontaneous IPSCs whereas spike-independent mIPSCs remained unchanged. It was suggested that Noopept mediates its effect due to the activation of inhibitory interneurons terminating

  5. Influence of different histidine sources and zinc supplementation of broiler diets on dipeptide content and antioxidant status of blood and meat.

    PubMed

    Kope?, W; Jamroz, D; Wiliczkiewicz, A; Biazik, E; Pudlo, A; Hikawczuk, T; Skiba, T; Korzeniowska, M

    2013-01-01

    1. The objective of this study was to investigate how a diet containing spray-dried blood cells (SDBC) (4%) with or without zinc (Zn) would affect the concentration of two histidine heterodipeptides and the antioxidant status of broiler blood and breast muscles. 2. The study was carried out on 920 male Flex chickens randomly assigned to 4 dietary treatments: I - control, II - diet I with SDBC, III - diet I with SDBC and supplemented with Zn and IV - diet I supplemented with L-histidine. Birds were raised on floor littered with wood shavings, given free access to water and fed ad libitum. Performance indices were measured on d 1, 21 and 42. 3. The activity of antioxidant enzymes superoxide dismutase, catalase and glutathione peroxidase was analysed in plasma, erythrocytes and muscle tissue. The total antioxidant capacity of plasma and breast muscles was measured by 2,2-azinobis-(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging ability, as well as by ferric reducing antioxidant power (FRAP). Carnosine/anserine content of meat and plasma were determined using HPLC. Diets and breast muscles were analysed for amino acid profile and selected microelement content. 4. Histidine supplementation of the diet increased glutathione peroxidase activity in plasma and superoxide dismutase activity in erythrocytes. Moreover, the addition of SDBC or pure histidine in the diet increased histidine dipeptide content and activated enzymatic and non-enzymatic antioxidant systems in chicken blood and muscles. However, it led to lower growth performance indices. 5. The enrichment of broiler diets with Zn increased the antioxidant potential and the activity of superoxide dismutase in plasma, which was independent of the histidine dipeptide concentration. Zn supplementation combined with SDBC in a broiler diet led to the increase of superoxide dismutase and glutathione peroxidase activity, but it did not affect the radical-scavenging or ferric iron reduction abilities of muscles. PMID:23768017

  6. Daily and Seasonal Rhythms in Human Mucosa Phospholipid Fatty Acid Composition.

    PubMed

    Ruf, Thomas; Arnold, Walter

    2015-08-01

    Fatty acids (FAs) can exert important physiological effects: for example, as precursors of eicosanoids, as signaling molecules, and, in particular, as parts of phospholipids, the major constituents of cell membranes. Animals can remodel cell membranes in terms of their FA composition in response to environmental conditions, and even endothermic mammals exhibit seasonal cycles in the FA makeup of membranes. Previous evidence pointed to the existence of both seasonal and daily cycles in phospholipid composition of human cell membranes. Therefore, we used a noninvasive method to collect human mucosa cells over 1 year in 20 healthy subjects, and we determined seasonal and daily rhythmicity of phospholipid FA content. Our results show that significant daily rhythms were detectable in 11 of 13 FAs and were largely synchronous among subjects. Also, these daily rhythms showed stable phase relationships between different FAs within subjects. In contrast, yearly rhythms in phospholipid FA content were statistically significant in only ~50% of subjects and were asynchronous between subjects. These results support the view that while human physiology is still dominated by geophysical sunrise and sunset, resulting in strong daily cycles, seasonal rhythms are less well defined, at least in Western societies. We suggest that the main physiological function underlying rhythms in cell membrane composition is the regulation of the activity of transmembrane proteins, such as ion pumps, which can be strongly affected by the fatty acyl chains of phospholipids in the surrounding membrane bilayer. Hence, among a multitude of other functions, cycles in membrane FA composition may be involved in generating the daily rhythm of metabolic rate. Rhythms in certain membrane FAs, namely polyunsaturated and monounsaturated FAs that are known to affect health, could be also involved in daily and seasonal rhythms of diseases and death. PMID:26045067

  7. Surface-induced self-assembly of dipeptides onto nanotextured surfaces.

    PubMed

    Demirel, Gokhan; Buyukserin, Fatih

    2011-10-18

    There is an increasing interest for the utilization of biomolecules for fabricating novel nanostructures due to their ability for specific molecular recognition, biocompatibility, and ease of availability. Among these molecules, diphenylalanine (Phe-Phe) dipeptide is considered as one of the simplest molecules that can generate a family of self-assembly based nanostructures. The properties of the substrate surface, on which the self-assembly process of these peptides occurs, play a critical role. Herein, we demonstrated the influence of surface texture and functionality on the self-assembly of Phe-Phe dipeptides using smooth silicon surfaces, anodized aluminum oxide (AAO) membranes, and poly(chloro-p-xylylene) (PPX) films having columnar and helical morphologies. We found that helical PPX films, AAO, and silicon surfaces induce similar self-assembly processes and the surface hydrophobicity has a direct influence for the final dipeptide structure whether being in an aggregated tubular form or creating a thin film that covers the substrate surface. Moreover, the dye staining data indicates that the surface charge properties and hence the mechanism of the self-assembly process are different for tubular structures as opposed to the peptidic film. We believe that our results may contribute to the control of surface-induced self-assembly of peptide molecules and this control can potentially allow the fabrication of novel peptide based materials with desired morphologies and unique functionalities for different technological applications. PMID:21879773

  8. [Dipeptide nootropic agent GVS-111 prevents accumulation of the lipid peroxidation products during immobilization].

    PubMed

    Lysenko, A V; Uskova, N I; Ostrovskaia, R U; Gudasheva, T A; Voronina, T A

    1997-01-01

    Immobilization of rats in a narrow plastic chamber for 24 h caused a sharp increase in the level of diene conjugates and the content of schiff bases in the synaptosomes of the brain cortex as well as accumulation of extraerythrocytic hemoglobin in blood serum. The dipeptide nootropic agent GVS-111 (ethyl ether of phenylacetylprolylglycine), when administered 15 and particularly 60 min before immobilization reduced the accumulation of these products of lipid peroxidation in the brain and blood. GVS-111 demonstrated these signs of its antioxidant effect after a single i.p. injection in doses of 0.12 and 0.5 mg/kg. Pyracetam produced a similar effect on the listed parameters in injection in a dose of 300 mg/kg for three successive days. The protective effect of the new pyracetam dipeptide analog GVS-111 in relation to activation of free-radical processes induced by immobilization is additional proof of the antistress action of this dipeptide. PMID:9483398

  9. Nondestructive determination of oil content and fatty acid composition in perilla seeds by near-infrared spectroscopy.

    PubMed

    Kim, Kwan Su; Park, Si Hyung; Choung, Myoung Gun

    2007-03-01

    Near-infrared reflectance spectroscopy (NIRS) was used as a rapid and nondestructive method to determine the oil content and fatty acid composition in intact seeds of perilla [Perilla frutescens var. japonica (Hassk.) Hara] germplasms in Korea. A total of 397 samples (about 2 g of intact seeds) were scanned in the reflectance mode of a scanning monochromator, and the reference values for the oil content and fatty acid composition were measured by gravimetric method and gas-liquid chromatography, respectively. Calibration equations for oil and individual fatty acids were developed using modified partial least-squares regression with internal cross validation (n = 297). The equations for oil and oleic and linolenic acid had lower standard errors of cross-validation (SECV), higher R2 (coefficient of determination in calibration), and higher ratio of unexplained variance divided by variance (1-VR) values than those for palmitic, stearic, and linoleic acid. Prediction of an external validation set (n = 100) showed significant correlation between reference values and NIRS estimated values based on the standard error of prediction (SEP), r2 (coefficient of determination in prediction), and the ratio of standard deviation (SD) of reference data to SEP. The models for oil content and major fatty acids, oleic and linolenic acid, had relatively higher values of SD/SEP(C) and r2 (more than 3.0 and 0.9, respectively), thereby characterizing those equations as having good quantitative information, whereas those of palmitic, stearic, and linoleic acid had lower values (below 2.0 and 0.7, respectively), unsuitable for screening purposes. The results indicated that NIRS could be used to rapidly determine oil content and fatty acid composition (oleic and linolenic acid) in perilla seeds in the breeding programs for development of high-quality perilla oil. PMID:17288449

  10. Monitoring of ppm level humic acid in surface water using ZnO-chitosan nano-composite as fluorescence probe

    NASA Astrophysics Data System (ADS)

    Basumallick, Srijita; Santra, Swadeshmukul

    2015-05-01

    Surface water contains natural pollutants humic acid (HA) and fulvic acid at ppm level which form carcinogenic chloro-compounds during chlorination in water treatment plants. We report here synthesis of ZnO-chitosan (CS) nano-composites by simple hydrothermal technique and examined their application potential as fluorescent probe for monitoring ppm level HA. These ZnO-CS composites have been characterized by HRTEM, EDX, FTIR, AFM and Fluorescence Spectra. HRTEM images show the formation of ZnO-CS nano-composites of average diameter of 50-250 nm. Aqueous dispersions of these nano-composites show fluorescence emission at 395 nm when excited at 300 nm which is strongly quenched by ppm level HA indicating their possible use in monitoring ppm level HA present in surface water.

  11. The Role of Tetraether Lipid Composition in the Adaptation of Thermophilic Archaea to Acidity

    PubMed Central

    Boyd, Eric S.; Hamilton, Trinity L.; Wang, Jinxiang; He, Liu; Zhang, Chuanlun L.

    2013-01-01

    Diether and tetraether lipids are fundamental components of the archaeal cell membrane. Archaea adjust the degree of tetraether lipid cyclization in order to maintain functional membranes and cellular homeostasis when confronted with pH and/or thermal stress. Thus, the ability to adjust tetraether lipid composition likely represents a critical phenotypic trait that enabled archaeal diversification into environments characterized by extremes in pH and/or temperature. Here we assess the relationship between geochemical variation, core- and polar-isoprenoid glycerol dibiphytanyl glycerol tetraether (C-iGDGT and P-iGDGT, respectively) lipid composition, and archaeal 16S rRNA gene diversity and abundance in 27 geothermal springs in Yellowstone National Park, Wyoming. The composition and abundance of C-iGDGT and P-iGDGT lipids recovered from geothermal ecosystems were distinct from surrounding soils, indicating that they are synthesized endogenously. With the exception of GDGT-0 (no cyclopentyl rings), the abundances of individual C-iGDGT and P-iGDGT lipids were significantly correlated. The abundance of a number of individual tetraether lipids varied positively with the relative abundance of individual 16S rRNA gene sequences, most notably crenarchaeol in both the core and polar GDGT fraction and sequences closely affiliated with Candidatus Nitrosocaldus yellowstonii. This finding supports the proposal that crenarchaeol is a biomarker for nitrifying archaea. Variation in the degree of cyclization of C- and P-iGDGT lipids recovered from geothermal mats and sediments could best be explained by variation in spring pH, with lipids from acidic environments tending to have, on average, more internal cyclic rings than those from higher pH ecosystems. Likewise, variation in the phylogenetic composition of archaeal 16S rRNA genes could best be explained by spring pH. In turn, the phylogenetic similarity of archaeal 16S rRNA genes was significantly correlated with the similarity in the composition of C- and P-iGDGT lipids. Taken together, these data suggest that the ability to adjust the composition of GDGT lipid membranes played a central role in the diversification of archaea into or out of environments characterized by extremes of low pH and high temperature. PMID:23565112

  12. Fatty acid composition of retail cuts trimmed to different external fat levels from choice, select, and standard beef grade carcasses 

    E-print Network

    Sullivan, Dana Renee

    1988-01-01

    by about 20 percent (Coleman et al. , 1988) . The effect of cooking on the composition of beef cuts that are closely or completely trimmed of fat is unknown. In addition, the effects of different cooking methods and different degrees of doneness... grade, fat trim level, ard degree of doneness on the fatty acid composition of retail cuts of beef. Therefore, the objectives of this study were to compare these effects. MATERIALS AND METHODS Texas Agricultural Experiment Station personnel were...

  13. Changes of phospholipid fatty acid composition in the digestive gland of the mollusc Littorina saxatilis , caused by trematode larvae

    Microsoft Academic Search

    E. S. Arakelova; M. A. Chebotareva; S. A. Zabelinskii; E. P. Shukolyukova

    2007-01-01

    Lipids in the digestive gland of the mollusc Littorina saxatilis from the White and Barents Seas were studied. Changes of their biochemical composition are discussed in the connection with\\u000a different temperature of the habitat and with infestation with trematode larvae. Comparative analysis of the fatty acid (FA)\\u000a composition of each of the phospholipids in intact molluscs has revealed essential differences.

  14. Determination of hydrogen peroxide scavenging activity of phenolic acids by employing gold nanoshells precursor composites as nanoprobes

    Microsoft Academic Search

    Xiaoyuan Ma; Hui Li; Jian Dong; Weiping Qian

    2011-01-01

    A series of phenolic acids were tested for their ability to scavenge hydrogen peroxide (H2O2) by using a novel enzyme-free, spectrophotometry assay. Gold nanoshells (GNSs) precursor composites were selected as the optical nanoprobes. The approach was based on the H2O2-induced growth of GNSs, which combines nanoscience with food\\/health research as an innovative detection scheme. The addition of phenolic acids inhibits

  15. Lipid changes in maturing oil-bearing plants. II. Changes in fatty acid composition of flax and safflower seed oils

    Microsoft Academic Search

    R. P. A. Sims; W. G. McGregor; A. G. Plessers; J. C. Mes

    1961-01-01

    Changes in the fatty acids composition of the oil in flax and safflower seed that occur during the seed-ripening period have\\u000a been measured. Concentrations of lipid or of specific fatty acid, expressed on a weight-per-seed basis, have been plotted\\u000a as functions of days after fertilization and of percentage of oil development. Relations between these two independent variables\\u000a have been established,

  16. Characterization and chemical composition of fatty acids content of watermelon and muskmelon cultivars in Saudi Arabia using gas chromatography/mass spectroscopy

    PubMed Central

    Albishri, Hassan M.; Almaghrabi, Omar A.; Moussa, Tarek A. A.

    2013-01-01

    Background: The growth in the production of biodiesel, which is principally fatty acid methyl esters (FAME), has been phenomenal in the last ten years because of the general desire to cut down on the release of greenhouse gases into the atmosphere, and also as a result of the increasing cost of fossil fuels. Objective: Establish whether there is any relationship between two different species (watermelon and muskmelon) within the same family (Cucurbitaceae) on fatty acid compositions and enumerate the different fatty acids in the two species. Materials and Methods: Extraction of fatty acids from the two species and preparation the extract to gas chromatography/mass spectroscopy analysis to determine the fatty acids compositions qualitatively and quantitatively. Results: The analyzed plants (watermelon and muskmelon) contain five saturated fatty acids; tetrdecanoic acid, pentadecanoic acid, hexadecanoic acid, heptadecanoic acid and octadecanoic acid with different concentrations, while muskmelon contains an extra saturated fatty acid named eicosanoic acid. The watermelon plant contains five unsaturated fatty acids while muskmelon contains three only, the two plants share in two unsaturated fatty acids named 9-hexadecenoic acid and 9-octadecenoic acid, the muskmelon plant contains higher amounts of these two acids (2.04% and 10.12%, respectively) over watermelon plant (0.88% and 0.25%, respectively). Conclusion: The chemical analysis of watermelon and muskmelon revealed that they are similar in saturated fatty acids but differ in unsaturated fatty acids which may be a criterion of differentiation between the two plants. PMID:23661995

  17. Sulfuric acid doped poly diaminopyridine/graphene composite to remove high concentration of toxic Cr(VI).

    PubMed

    Dinda, Diptiman; Kumar Saha, Shyamal

    2015-06-30

    Sulfuric acid doped diaminopyridine polymers are synthesized in situ on graphene oxide surface via mutual oxidation-reduction technique. Exploiting large and highly porous surface, we have used this polymer composite as an adsorbent to remove high concentration of toxic Cr(VI) from water. It shows very high adsorption capacity (609.76 mg g(-1)) during removal process. The composite takes only 100 min to remove high concentration of 500 mg L(-1) Cr(VI) from water. Interesting features for this material is the enhancement of removal efficiency at lower acidic condition due to the formation of acid doped emeraldine salt during polymerization. XPS and AAS measurements reveal that our prepared material mainly follows reduction mechanism at higher acidic condition while anions exchange mechanism at lower acidic condition during the removal experiments. Good recycling ability with ? 92% removal efficiency after fifth cycle is also noticed for this material. Easy preparation, superior stability in acidic condition, remarkable removal efficiency and excellent recycling ability make this polymer composite an efficient material for modern filtration units in waste water purification. PMID:25771215

  18. Effect of unialgal diets on the composition of fatty acids and sterols in juvenile ark shell Tegillarca granosa Linnaeus.

    PubMed

    Xu, Jilin; Zhou, Haibo; Yan, Xiaojun; Zhou, Chengxu; Zhu, Peng; Ma, Bin

    2012-04-18

    This study has investigated the effects of six different unialgal diets ( Chaetoceros calcitrans , Platymonas helgolandica , Chlorella sp., Isochrysis galbana , Nannochloropsis oculata , and Pavlova viridis ) on the composition of fatty acids and sterols in juvenile ark shell Tegillarca granosa Linnaeus. The best feeding effects on the growth of shellfish were found in C. calcitrans, followed by I. galbana and P. viridis, whereas Chlorella sp. and N. oculata exhibited relatively poor effects. The fatty acid and sterol compositions in the six microalgae and the juvenile ark shell after feeding were analyzed, and 39 fatty acids and 18 sterols were identified. Although the results demonstrate a close correlation between the sterol compositions in algal species and juvenile ark shell, a similar correlation was not observed between fatty acids. In the juvenile ark shell fed microalgae, the ratio of total saturated fatty acids (SFA) rapidly decreases, whereas the proportion of total polyunsaturated fatty acids (PUFAs) increases considerably. The abundances of AA, EPA, and DHA increase most significantly in shellfish with better growth (fed C. calcitrans, I. galbana, and P. viridis). The number of sterol species is reduced, but the total sterol content in groups fed corresponding microalgae increases, and abundant plant sterols, instead of cholesterol, are accumulated in juvenile ark shell fed appropriate microalgae I. galbana and P. viridis. Therefore, to be more conducive to human health, I. galbana and P. viridis, of the six experimental microalgae, are recommended for artificial ark shell culture. PMID:22443233

  19. Fatty acid composition in tissues of the farmed Siberian sturgeon (Acipenser baerii).

    PubMed

    Nieminen, Petteri; Westenius, Eini; Halonen, Toivo; Mustonen, Anne-Mari

    2014-09-15

    The fatty acid (FA) compositions of the diet and diverse tissues of the farmed Siberian sturgeon (Acipenser baerii) were analyzed in detail to assess their nutritional quality. Twelve male fish were sampled for muscle, fat, liver, brain, gill, kidney and gonad and the tissue FA measured by gas-liquid chromatography. The FA profile of the diet diverged from the FA signatures of the tissues, where the sturgeons accumulated particular highly-unsaturated FA (HUFA). They were probably derived from the diet but, as previous studies have shown that fish can also have desaturase enzymes, endogenous synthesis of these FA cannot be excluded. The sturgeon muscle tissue contained HUFA in proportions comparable to those of other fish species that are considered good sources of n-3 polyunsaturated FA. The indices of atherogenicity and thrombogenicity were also within the values considered to be health-promoting. PMID:24767029

  20. Diatom valve distribution and sedimentary fatty acid composition in Larsen Bay, Eastern Antarctica Peninsula

    NASA Astrophysics Data System (ADS)

    Sañé, E.; Isla, E.; Pruski, A. M.; Bárcena, M. A.; Vétion, G.; DeMaster, D.

    2011-08-01

    During austral summer 2006-2007, five sediment cores were recovered from the Eastern Antarctic Peninsula (EAP) continental shelf. Microscopic observations and sediment fatty acid (FA) composition analyses were carried out to investigate whether the drastic changes at the sea surface in EAP may be reflected in the sedimentary record. A sharp decrease in the number of diatom valves was observed below 2 cm depth. This difference between the upper 2 cm of sediment and the deeper part of the sediment column was attributed to the drastic change in the upper water column conditions after the collapse of the ice shelves, which allowed the arrival of phytoplankton debris and fresh organic matter to the sea floor in EAP. The presence of bacterial-, zooplankton- and detrital-related FA throughout EAP cores suggests that there has been an input of older and more refractory organic matter into the region, presumably by lateral transport before the Larsen ice shelves disintegration.