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Detecting thermophilic proteins through selecting amino acid and dipeptide composition features.  


Detecting thermophilic proteins is an important task for designing stable protein engineering in interested temperatures. In this work, we develop a simple but efficient method to classify thermophilic proteins from mesophilic ones using the amino acid and dipeptide compositions. Since most of the amino acid and dipeptide compositions are redundant, we propose a new forward floating selection technique to select only a useful subset of these compositions as features for support vector machine-based classification. We test the proposed method on a benchmark data set of 915 thermophilic and 793 mesophilic proteins. The results show that our method using 28 amino acid and dipeptide compositions achieves an accuracy rate of 93.3% evaluated by the jackknife cross-validation test, which is higher not only than the existing methods but also than using all amino acid and dipeptide compositions. PMID:21547362

Nakariyakul, Songyot; Liu, Zhi-Ping; Chen, Luonan



ESLpred: SVM-based method for subcellular localization of eukaryotic proteins using dipeptide composition and PSI-BLAST  

Microsoft Academic Search

Automated prediction of subcellular localization of proteinsisanimportant stepinthefunctionalannota- tionofgenomes.Theexistingsubcellularlocalization prediction methods are based on either amino acid composition or N-terminal characteristics of the pro- teins.Inthispaper,supportvectormachine(SVM)has beenusedtopredictthesubcellularlocationofeukar- yotic proteins from their different features such as amino acid composition, dipeptide composition and physico-chemicalproperties.TheSVMmodulebased on dipeptide composition performed better than the SVM modules based on amino acid composition or physico-chemical properties. In addition,

Manoj Bhasin; G. P. S. Raghava



Density functional theory calculations on dipeptide gallic acid interaction  

NASA Astrophysics Data System (ADS)

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.

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



[Synthesis and biological activity of new glycyrrhizic acid conjugates with amino acids and dipeptides].  


New glycyrrhizic acid (GA) conjugates were synthesized with the use of tert-butyl esters of amino acids or benzyl esters of dipeptides; they contained two residues of L-amino acids (Met, Phe, Pro, and Ile or dipeptides Gly-Leu and Gly-Phe). Activation of GA carboxy groups was carried out with the help of N-hydroxysuccinimide, N,N'-dicyclohexylcarbodiimide, or N-hydroxybenzotriazole with dicyclohexylcarbodiimide. A proline-containing GA derivative is a low-toxic substance; it raises the level of agglutinins by 3.7 times in the blood of mice and 3 times that of hemolysins compared with the control. Dipeptide GA derivatives possess an expressed anti-HIV-1 activity in cultures of MT-4 cells and are 90-70 times less cytotoxic than azidothymidine. The selectivity index of the compounds exceeds those of GA by 110 and 34 times, respectively. PMID:19928060

Baltina, L A; Kondratenko, R M; Baltina, L A; Baschenko, N Zh; Pliasunova, O A


A Concentrated Mixture of Amino Acids and Dipeptides for Total Parenteral Nutrition  

Microsoft Academic Search

Summary Using a subhuman primate (baboon) we have investigated the utility of a 20 % mixture of amino acids and dipeptides as the nitrogen source for total parenteral nutrition. The mixture, besides containing all 8 essential amino acids and a number of non-essential amino acids (glutamate, aspartate, arginine, histidine, serine, ornithine and alanine), contained 6 dipeptides (Gly-Ile, Gly-Leu, Gly-Val, Gly-Tyr,

J. A. Vazquez; G. A. Paleos; H. Lochs; K. Langer; M. Brandl; S. A. Adibi



Method for the synthesis of phosphinic acids from hypophosphites V. The synthesis of pseudo-?,?-dipeptides  

Microsoft Academic Search

Summary. The method for the synthesis of 2-substituted 2-hydroxycarbonylethyl-1-aminoalkylphosphinic acids (I) (pseudo-?,?-dipeptides) from ammonium and potassium hypophosphites (II) is described. The proposed route to the synthesis of pseudo-?,?-dipeptides consists in addition hypophosphite to acrylic compounds and formation of the first phosphorus–carbon bond with following addition of aminoacid fragment and formation of the second phosphorus–carbon bond. The key intermediates of the

L. F. Rozhko; V. V. Ragulin



Addition of amino acids and dipeptides to fullerene C{sub 60} giving rise to monoadducts  

SciTech Connect

The authors have developed a general method for the direct addition of amino acids and dipeptides of various structures to fullerene C{sub 60}. In all cases the addition involves the amino group. The reaction proceeds when the solutions of fullerene and an amino acid (or dipeptide) are mixed at 50-100 {degrees}C. The fullerene derivatives of the following amino acids and dipeptides have been obtained: glycine, p-aminobenzoic acid, {omega}-aminocaproic acid, L-proline, L-alanine, L-alanyl-Lalanine, D,L-alanyl-D,L-alanine, glycyl-L-valine. The adduct of methyl L-ananinate with C{sub 60} was also prepared.

Romanova, V.S.; Tsyryapkin, V.A.; Vol`pin, M.E. [A.N. Nesmeyanov Institute of Organoelement Compounds, Moscow (Russian Federation)] [and others



The Synthesis of a Dipeptide from its Component Amino Acids: Protecting Groups in the Elementary Organic Laboratory.  

ERIC Educational Resources Information Center

|A simple, three-step procedure for synthesizing a dipeptide from its component amino acids is described. The dipeptide synthesized uses inexpensive amino acids having hydrocarbon side-chains and can be observed in E/Z forms by nuclear magnetic resonance spectroscopy. Each step in the synthesis produces white crystalline products using standard…

Young, Paul E.; Campbell, Andrew



Asymmetric catalysis of the Strecker amino acid synthesis by a cyclic dipeptide  

Microsoft Academic Search

A novel cyclic dipeptide —cyclo[(S)-His-(S)-NorArg] — has been prepared which catalyzes an enantioselective version of the Strecker amino acid synthesis. The catalyst, when present in 2 mol % quantity in methanol solution, catalyzes the addition of hydrogen cyanide toN-alkylimines to afforda-amino nitriles in high yield and high enantiomeric excess. Furthermore, acid hydrolysis ofN-benzhydryl-a-amino nitriles afforded the correspondinga-amino acids directly. This

M. S. Iyer; K. M. Gigstad; N. D. Namdev; M. Lipton



Reactions of An Aromatic ?,?-Biradical with Amino Acids and Dipeptides in the Gas Phase  

PubMed Central

Gas-phase reactivity of a positively charged aromatic ?,?-biradical (N-methyl-6,8-didehydroquinolinium) was examined toward six aliphatic amino acids and fifteen dipeptides by using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR) and laser-induced acoustic desorption (LIAD). While previous studies have revealed that H-atom and NH2 abstractions dominate the reactions of related monoradicals with aliphatic amino acids and small peptides, several additional, unprecedented reaction pathways were observed for the reactions of the biradical. For amino acids, these are 2H-atom abstraction, H2O abstraction, addition – CO2, addition – HCOOH and formation of a stable adduct. The biradical reacts with aliphatic dipeptides similarly as with aliphatic amino acids, but undergoes also one additional reaction pathway, addition/C-terminal amino acid elimination (addition – CO – NHCHRC). These reactions are initiated by H-atom abstraction by the biradical from the amino acid or peptide, or nucleophilic addition of an NH2 or a HO group of the amino acid or peptide at the radical site at C-6 in the biradical. Reactions of the unquenched C-8 radical site then yield the products not observed for related monoradicals. The biradical reacts with aromatic dipeptides with an aromatic ring in N-terminus (i.e., Tyr-Leu, Phe-Val and Phe-Pro) similarly as with aliphatic dipeptides. However, for those aromatic dipeptides that contain an aromatic ring in the C-terminus (i.e., Leu-Tyr and Ala-Phe), one additional pathway, addition/N-terminal amino acid elimination (addition – CO – NHCHRN), was observed. This reaction is likely initiated by radical addition of the biradical at the aromatic ring in the C-terminus. Related monoradicals add to aromatic amino acids and small peptides, which is followed by C?-C? bond cleavage, resulting in side-chain abstraction by the radical. For biradicals, with one unquenched radical site after the initial addition, the reaction ultimately results in the loss of the N-terminal amino acid. Similar to monoradicals, the C-S bond in amino acids and dipeptides was found to be especially susceptible to biradical attack.

Fu, Mingkun; Li, Sen; Archibold, Enada; Yurkovich, Michael J.; Nash, John J.; Kenttamaa, Hilkka I.



Chiral recognition of amino acids and dipeptides by a water-soluble zinc porphyrin.  


A chiral water-soluble zinc porphyrin was optically resolved on a chiral HPLC column, and the binding of chiral amino acids and peptides to each of the enantiomers was examined spectrophotometrically in basic aqueous solution. The binding data apparently indicated that the zinc porphyrin has chiral selectivity for amino acids and dipeptides. This was reasonably explained in terms of the triple cooperation of coordination, Coulomb, and steric interactions of the chiral amino carboxylates with the porphyrin. A compensatory relationship among the thermodynamic parameters for chiral recognition was also shown. PMID:14966952

Imai, Hiroyasu; Munakata, Hiroki; Uemori, Yoshio; Sakura, Naoki



Reactions of an aromatic ?,?-biradical with amino acids and dipeptides in the gas phase  

Microsoft Academic Search

Gas-phase reactivity of a positively charged aromatic ?,?-biradical (N-methyl-6,8-didehydroquinolinium) was examined toward six aliphatic amino acids and 15 dipeptides by using Fourier transform\\u000a ion cyclotron resonance mass spectrometry (FT-ICR) and laser-induced acoustic desorption (LIAD). While previous studies have\\u000a revealed that H-atom and NH2 abstractions dominate the reactions of related monoradicals with aliphatic amino acids and small peptides, several additional,\\u000a unprecedented

Mingkun Fu; Sen Li; Enada Archibold; Michael J. Yurkovich; John J. Nash; Hilkka I. Kenttämaa



The formation of dipeptides from amino acids and the 2?(3?)-glycyl ester of an adenylate  

Microsoft Academic Search

Summary The yields of dipeptide obtained from the reaction of 0.2M 2'(3')-O-(glycyl)-adenosine-5'-(O-methylphosphate) and 0.2M amino acid at pH 8.2 ranged from 0.1% to 35.5% for a group of 15 amino acids. The yields of glyser (35.3%), gly-cys (11.8%) and gly-thr (5.4%) were considerably greater than dipeptide yields obtained from any of the other 12 amino acids (? 1.7%). Aminolysis of

Arthur L. Weber; Leslie E. Orgel



Influence of lipid composition on physicochemical properties of nanoliposomes encapsulating natural dipeptide antioxidant l-carnosine.  


Natural dipeptide antioxidants (l-carnosine) are recieving increasing attention because of their noticeable potential as biopreservatives in food recent technology. Encapsulation of antioxidants by nanoliposomes could represent an ameliorative approach to overcome the problems related to the direct application of these antioxidant peptides in food. In this study, nanoliposomes prepared from different lipids (DOPC, POPC and DPPC) by thin film hydration method, were assessed by considering their size, ?-potential, phase transition temperature and fluidity. One important parameter of interest in this article was to compare the encapsulation efficacy of l-carnosine in three different nanoliposomes using a rapid and precise approach (1)H NMR without the need for physical separation of entrapped and non-entrapped l-carnosine. Furthermore, the morphology of small unilamellar nanoliposomes with different compositions on mica surface was investigated using Atomic Force Microscopy. PMID:23107672

Maherani, Behnoush; Arab-Tehrany, Elmira; Kheirolomoom, Azadeh; Cleymand, Franck; Linder, Michel



AminoAcid and Dipeptide Derivatives of 2-(6-ethyl-4-oxo-3-(4-phenyl-4 H -1,2,4-triazol-3-yl)-4 H -chromen-7-yloxy)acetic Acid  

Microsoft Academic Search

Chromones modified by triazole, amino acids, and dipeptides were prepared by condensation of the N-hydroxysuccinimide ester\\u000a of 2-(6-ethyl-4-oxo-3-(4-phenyl-4H-1,2,4-triazol-3-yl)-4H-chromen-7-yloxy)acetic acid with salts of amino acids or dipeptides.\\u000a The dipeptide derivatives were also synthesized by extending the chain of amino acids.

T. V. Shokol; V. V. Semenyuchenko; S. V. Shilin; A. V. Turov; A. S. Ogorodniichuk; V. P. Khilya



Amino acid specificity of glycation and protein–AGE crosslinking reactivities determined with a dipeptide SPOT library  

Microsoft Academic Search

Advanced glycation end products (AGEs) contribute to changes in protein conformation, loss of function, and irreversible crosslinking. Using a library of dipeptides on cellulose membranes (SPOT library), we have developed an approach to systematically assay the relative reactivities of amino acid side chains and the N-terminal amino group to sugars and protein–AGEs. The sugars react preferentially with cysteine or tryptophan

Dorothee Schicktanz; Andrea Behme; Manfred Gerlach; Peter Riederer; Dieter Palm; Reinhard Schinzel; Gerald Münch



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

Microsoft Academic Search

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-

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



Identification of amide bands in the FTIR spectra of protected amino acids and dipeptides. II. Solution spectra  

Microsoft Academic Search

Protected amino acids and dipeptides of the type Boc-X-NHCH3 and Boc-X-Y-NHCH3 (where X?Pro, Val, Y?Thr and Boc=t-butyloxycarbonyl) have been investigated by infrared spectroscopy in solution phase. The NH sretching and CO stretching regions of the spectra were studied by means of Fourier self-deconvolution and curve fitting to determine the number, frequency and intensity of band components. The results were interpreted

G. Jalsovszky; S. Holly; M. Hollósi



Structural and enzymatic characterization of BacD, an L-amino acid dipeptide ligase from Bacillus subtilis.  


BacD is an ATP-dependent dipeptide ligase responsible for the biosynthesis of L-alanyl-L-anticapsin, a precursor of an antibiotic produced by Bacillus spp. In contrast to the well-studied and phylogenetically related D-alanine: D-alanine ligase (Ddl), BacD synthesizes dipeptides using L-amino acids as substrates and has a low substrate specificity in vitro. The enzyme is of great interest because of its potential application in industrial protein engineering for the environmentally friendly biological production of useful peptide compounds, such as physiologically active peptides, artificial sweeteners and antibiotics, but the determinants of its substrate specificity and its catalytic mechanism have not yet been established due to a lack of structural information. In this study, we report the crystal structure of BacD in complex with ADP and an intermediate analog, phosphorylated phosphinate L-alanyl-L-phenylalanine, refined to 2.5-Å resolution. The complex structure reveals that ADP and two magnesium ions bind in a manner similar to that of Ddl. However, the dipeptide orientation is reversed, and, concomitantly, the entrance to the amino acid binding cavity differs in position. Enzymatic characterization of two mutants, Y265F and S185A, demonstrates that these conserved residues are not catalytic residues at least in the reaction where L-phenylalanine is used as a substrate. On the basis of the biochemical and the structural data, we propose a reaction scheme and a catalytic mechanism for BacD. PMID:22407814

Shomura, Yasuhito; Hinokuchi, Emi; Ikeda, Hajime; Senoo, Akihiro; Takahashi, Yuichi; Saito, Jun-ichi; Komori, Hirofumi; Shibata, Naoki; Yonetani, Yoshiyuki; Higuchi, Yoshiki



Arginyl-Glutamine Dipeptide or Docosahexaenoic Acid Attenuates Hyperoxia-induced Small Intestinal Injury in Neonatal Mice  

PubMed Central

Background and Objective Supplementation studies of glutamine, argi-nine, and docosahexaenoic acid (DHA) have established the safety of each of these nutrients in neonates; however, the potential for a more stable and soluble dipeptide, arginyl-glutamine (Arg-Gln) or DHA with anti-inflammatory properties, to exert benefits on hyperoxia-induced intestinal injury has not been investigated. Arg-Gln dipeptide has been shown to prevent retinal damage in a rodent model of oxygen-induced injury. The objective of the present study was to investigate whether Arg-Gln dipeptide or DHA could also attenuate markers of injury and inflammation to the small intestine in this same model. Methods Seven-day-old mouse pups were placed with their dams in 75% oxygen for 5 days. After 5 days of hyperoxic exposure (P7–P12), pups were removed from hyperoxia and allowed to recover in atmospheric conditions for 5 days (P12–P17). Mouse pups received Arg-Gln (5 g · kg–1 · day–1) or DHA (5 g · kg–1 · day–1) or vehicle orally started on P12 through P17. Distal small intestine (DSI) histologic changes, myeloperoxidase (MPO), lactate dehydrogenase (LDH), inflammatory cytokines, and tissue apoptosis were evaluated. Results Hyperoxic mice showed a greater distortion of overall villus structure and with higher injury score (P < 0.05). Arg-Gln dipeptide and DHA supplementation groups were more similar to the room air control group. Supplementation of Arg-Gln or DHA reduced hyperoxia-induced MPO activity (P < 0.05). Supplementation of Arg-Gln or DHA returned LDH activity to the levels of control. Hyperoxia induced apoptotic cell death in DSIs, and both Arg-Gln and DHA reversed this effect (P < 0.05). Conclusions Supplementation with either Arg-Gln or DHA may limit some inflammatory and apoptotic processes involved in hyperoxic-induced intestinal injury in neonatal mice.

Li, Nan; Ma, Liya; Liu, Xueyan; Shaw, Lynn; Calzi, Sergio Li; Grant, Maria B.; Neu, Josef



A Molecular Dynamics Simulation Study of Two Dipeptide Based Molecular Micelles: Effect of Amino Acid Order  

PubMed Central

Molecular dynamics (MD) simulations were used to compare the structures of the chiral molecular micelles (MM) poly-(sodium undecyl-(L,L)-leucine-valine) (poly(SULV)) and poly-(sodium undecyl-(L,L)-valine-leucine) (poly (SUVL)). Both MM contained polymerized surfactant monomers tenninated by chiral dipeptide headgroups. The study was undertaken to investigate why poly(SULV) is generally a better chiral selector compared to poly(SUVL) in electrokinetic chromatography separations. When comparing poly(SULV) to poly(SUVL), poly(SULV) had the more conformational flexible dipeptide headgroup and hydrogen bond analyses revealed that the poly(SULV) headgroup conformation allowed a larger number of intramolecular hydrogen bonds to form between monomer chains. In addition, a larger number of water molecules surrounded the chiral centers of the poly(SULV) molecular micelle. Poly(SULV) was also found to have a larger solvent accessible surface area (SASA) than poly(SUVL) and fluctuations in the poly(SULV) SASA during the MD simulation allowed dynamic monomer chain motions expected to be important in chiral recognition to be identified. Finally, approximately 50% of the Na+ counterions were found in the first three solvation shells surrounding both MM, with the remainder located in the bulk. Overall the MD simulations point to both greater headgroup flexibility and solvent and analyte access to the chiral centers of the dipeptide headgroup as factors contributing to the enhanced chiral selectivity observed with poly(SULV).

Morris, Kevin F.; Billiot, Eugene J.; Billiot, Fereshteh H.; Lipkowitz, Kenny B.; Southerland, William M.; Fang, Yayin



Branched-chain amino acid-containing dipeptides, identified from whey protein hydrolysates, stimulate glucose uptake rate in L6 myotubes and isolated skeletal muscles.  


In earlier studies we showed that dietary whey protein increased skeletal muscle and liver glycogen content in exercise-trained rats. However, little is known about whether ingredients of whey protein stimulate skeletal muscle glycogen accumulation. The aim of this study was to identify bioactive peptides in whey protein hydrolysates (WPH) which stimulated glucose uptake and glycogen synthesis rate in skeletal muscles. Branched-chain amino acid (BCAA)-containing dipeptides in WPH were identified using LC/MS/MS. L6 myotubes and isolated epitrochlearis muscles were used for the glucose uptake assays. The myotubes and muscles were incubated with or without 1 mM dipeptides, LY294002 a phosphoinositide 3-kinase (PI3-kinase) inhibitor, or GF102903X an atypical protein kinase C (aPKC) inhibitor, followed by measurement of 2-deoxyglucose uptake. Isolated muscles were incubated for 3 h with or without 1 mM Ile-Leu to determine glycogen synthesis rate. The BCAA-containing dipeptides, Ile-Val, Leu-Val, Val-Leu, Ile-Ile, Leu-Ile, Ile-Leu, and Leu-Leu were detected in the WPH by LC/MS/MS. These dipeptides caused significant stimulation in glucose uptake rate in the L6 myotubes. Ile-Leu, the main component in WPH, also stimulated glucose uptake in isolated skeletal muscles. Stimulation of glucose uptake by Ile-Leu was completely inhibited by treatment with either LY294002, or GF109203X in both L6 cells and isolated muscles. Ile-Leu increased glycogen contents in isolated muscles. These results suggest that BCAA-containing bioactive dipeptides in WPH stimulate glucose uptake in skeletal muscles via the PI3-kinase and aPKC pathways, resulting in increased skeletal muscle glycogen contents. PMID:19352067

Morifuji, Masashi; Koga, Jinichiro; Kawanaka, Kentaro; Higuchi, Mitsuru



[Analgesic activity of dipeptide Tyr-Pro].  


The effect of dipeptide Tyr-Pro, present in representatives of most families of opioid peptides, and two its analogs, Tyr-Pro-NH2 and Tyr-Pro-OMe, on analgesic activity was studied in different tests (tail-flick test, tail pinch (Haffner's) test, formalin test, and acetic acid writing test) describing different organization levels of pain sensitivity. Intraperitoneal administration of the dipeptide decreased the pain threshold in all above-mentioned tests. Coadministration of the dipeptide and naloxone or naloxone methiodide insignificantly decreased the dipeptide analgesic effect in the tail-flick and acetic acid writing tests. Its analogs Tyr-Pro-NH2 and Tyr-Pro-OMe demonstrated a similar analgesic activity in the tail-flick test and a higher activity in the acetic acid writing test. Administration of individual amino acids (Tyr or Pro) or their mixture had no effect on the pain threshold. PMID:18491563

Guzevatykh, L S; Voronina, T A; Emel'ianova, T G; Andreeva, L A; Alfeeva, L Iu; Seredenin, S B; Miasoedov, N F


Effect of a dipeptide-enriched diet in an adult Drosophila melanogaster laboratory strain.  


Here we present free amino acid profiles for Drosophila melanogaster adults. Imidazol dipeptides anserine and carnosine, which are abundant in mammalian muscle tissue, are not present in Drosophila. Dipeptide-enriched food altered the amino acid balance, suggesting that the free amino acid content is nutrition-dependent and probably mediated by dipeptides. PMID:23563531

Shiotani, Shigenobu; Yanai, Nobuya; Suzuki, Takanori; Tujioka, Shiho; Sakano, Yurie; Yamakawa-Kobayashi, Kimiko; Kayashima, Yasunari



Phenyl Radical-Induced Damage to Dipeptides  

PubMed Central

Laser-induced acoustic desorption (LIAD) incorporated with Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR) has been utilized to investigate phenyl radical-induced damage to dipeptides in the gas phase. Based on the product branching ratios measured for the reactions of two different positively-charged phenyl radicals with seventeen different dipeptides, the overall order of susceptibility to attack of the different sites in the dipeptides was determined to be: heteroaromatic side chain ? S atom in SCH3 group > H atom in SH group > H atom in CH group > aromatic side chain > S atom in SH group > NH2 in side chain > N-terminal NH2 > COOH in side chain ? C-terminal COOH. The amino acid sequence also influences the selectivity of these reactions. As expected, the ability of a phenyl radical to damage dipeptides increases as the electrophilicity of the phenyl radical increases.

Li, Sen; Fu, Mingkun; Habicht, Steven C.; Pates, George O.; Nash, John J.; Kenttamaa, Hilkka I.



A dipeptide and an amino acid present in whey protein hydrolysate increase translocation of GLUT-4 to the plasma membrane in Wistar rats.  


Whey protein hydrolysate (WPH) is capable of increasing muscle glycogen reserves and of concentrating the glucose transporter in the plasma membrane (PM). The objective of this study was to determine which WPH components could modulate translocation of the glucose transporter GLUT-4 to the PM of animal skeletal muscle. Forty-nine animals were divided into 7 groups (n=7) and received by oral gavage 30% glucose plus 0.55 g/kg body mass of the following WPH components: (a) control; (b) WPH; (c) L-isoleucine; (d) L-leucine; (e) L-leucine plus L-isoleucine; (f) L-isoleucyl-L-leucine dipeptide; (g) L-leucyl-L-isoleucine dipeptide. After receiving these solutions, the animals were sacrificed and the GLUT-4 analysed by western blot. Additionally, glycogen, glycaemia, insulin and free amino acids were also determined by standard methods. Of the WPH components tested, the amino acid L-isoleucine and the peptide L-leucyl-L-isoleucine showed greater efficiency in translocating GLUT-4 to the PM and of increasing glucose capture by skeletal muscle. PMID:23561181

Morato, P N; Lollo, P C B; Moura, C S; Batista, T M; Carneiro, E M; Amaya-Farfan, J



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)

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.

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



Novel dipeptide nanoparticles for effective curcumin delivery  

PubMed Central

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.

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



From macrocycle dipeptide lactams to azabicyclo[X.Y.0]alkanone amino acids: a transannular cyclization route for peptide mimic synthesis.  


[reaction: see text] Macrocyclic and fused bicyclic dipeptides are complementary motifs for mimicry of different types of beta-turn geometry. Macrocyclic dipeptide mimics have served as precursors for the synthesis of their bicyclic counterparts using electrophilic transannular cyclizations of 9- and 10-membered ring lactams 9-12 to form azabicyclo[4.3.0]- and -[5.3.0]alkanone amino esters 13-16. PMID:16774273

Surprenant, Simon; Lubell, William D



Dipeptides in nutrition and therapy: cyanophycin-derived dipeptides as natural alternatives and their biotechnological production  

Microsoft Academic Search

The numerous physiological functions of the nonessential amino acid L-aspartate, the semi-essential amino acid L-arginine,\\u000a and the essential amino acid L-lysine, made them attractive for a wide range of nutritional and\\/or therapeutic applications.\\u000a Furthermore, the administration of these amino acids as mixtures or as dipeptides for higher bioavailability is scientifically\\u000a approved, and various commercial products of these forms are already

Ahmed Sallam; Alexander Steinbüchel



Bradykinin antagonists modified with dipeptide mimetic beta-turn inducers.  


Bradykinin (BK) is involved in a wide variety of pathophysiological processes. Potent BK peptide antagonists can be developed introducing constrained unnatural amino acids, necessary to force the secondary structure of the molecule. In this paper, we report a structure-activity relationship study of two peptide analogues of the potent B2 antagonist HOE 140 by replacing the D-Tic-Oic dipeptide with conformationally constrained dipeptide mimetic beta-turn inducers. PMID:16504505

Alcaro, Maria C; Vinci, Valerio; D'Ursi, Anna M; Scrima, Mario; Chelli, Mario; Giuliani, Sandro; Meini, Stefania; Di Giacomo, Marcello; Colombo, Lino; Papini, Anna Maria



Inhibition of LiCl-induced conditioning of anticipatory nausea in rats following immune system stimulation: comparing the immunogens lipopolysaccharide, muramyl dipeptide, and polyinosinic: polycytidylic acid.  


The effects of the bacterial endotoxins, lipopolysaccharide (LPS) and muramyl dipeptide (MDP; Experiment 1), and the viral mimetic, polyinosinic: polycytidylic acid (poly I:C; Experiment 2), on the acquisition of "conditioned gaping" behavior in the rodent model of LiCl-induced anticipatory nausea were examined. Experimentally naïve adult male Long-Evans rats were injected (intraperitoneal, i.p.) with either 200 ?g/kg LPS, 1.6 mg/kg MDP, or 0.9% saline (Experiment 1), or 4.0 mg/kg poly I:C or 0.9% saline (Experiment 2), 90 min prior to treatment with 127 mg/kg LiCl or saline control and immediately placed into a distinctive context for 30 min (repeated over 4 conditioning days, spaced 72 h apart). On a drug-free test day (72 h following conditioning day 4), each animal was re-exposed to the context for 10 min, and orofacial and aversive behavioral responses were video recorded and analyzed. The results showed that pre-treatment with LPS, MDP (Experiment 1), or poly I:C (Experiment 2) prior to LiCl+context conditioning significantly impaired the establishment of conditioned gaping behavior, thus blocking the acquisition of anticipatory nausea. Results varied in regards to peripheral acute-phase response sickness behaviors, with significantly reduced weight loss in LPS-treated animals, less robust weight loss in poly I:C-treated animals, and no significant reductions in body weight in MDP-treated animals. The learning impairments observed in the current study suggest that endotoxin treatment with bacterial and viral endotoxin may have stronger central effects on learning and memory behavior, relative to peripheral effects on body weight and other sickness-related responses. PMID:22342813

Cloutier, Caylen J; Rodowa, Melinda-Sue; Cross-Mellor, Shelley K; Chan, Melissa Y T; Kavaliers, Martin; Ossenkopp, Klaus-Peter



Design, synthesis, and application of azabicyclo[X.Y.0]alkanone amino acids as constrained dipeptide surrogates and peptide mimics.  


Azabicyclo[X.Y.0]alkanone amino acids are challenging synthetic targets and useful tools for studying structure-activity relationships of native peptide ligands. They have been employed to increase potency and stability in conformationally rigid enzyme inhibitors and receptor ligands. Since last reviewed in 1997, activity in their synthesis and application has increased significantly and access is now available to a wider diversity of these peptide mimics. This review focuses on recent syntheses of these heterocyclic amino acids and their application in the investigation of biologically active peptides and peptide mimics. PMID:15795926

Cluzeau, Jérôme; Lubell, William D



Confirmation of D-aspartic acid in the novel dipeptide beta-aspartylglycine isolated from tissue extract of Aplysia kurodai.  

PubMed Central

A novel o-phthalaldehyde-reactive compound was found in the h.p.l.c. chromatogram of Aplysia kurodai extract. This compound was isolated by ion-exchange chromatography and preparative high-voltage paper electrophoresis. It was shown by optical-rotatory-dispersion spectrum and optical-resolution h.p.l.c. analysis that this compound consisted of equimolar amounts of D-aspartic acid and glycine. This compound resisted cleavage in the Edman reaction. This peptide was inferred to be beta-D-aspartylglycine, and this was confirmed by synthesis. beta-D-Aspartylglycine was detected in all tissues of Aplysia kurodai, with especially high concentrations in body wall (skin and muscle) and gill.

Sato, M; Yamaguchi, T; Kanno, N; Sato, Y



Muramyl dipeptide synergizes with Staphylococcus aureus lipoteichoic acid to recruit neutrophils in the mammary gland and to stimulate mammary epithelial cells.  


Staphylococcus aureus, a major pathogen for the mammary gland of dairy ruminants, elicits the recruitment of neutrophils into milk during mastitis, but the mechanisms are incompletely understood. We investigated the response of the bovine mammary gland to muramyl dipeptide (MDP), an elementary constituent of the bacterial peptidoglycan, alone or in combination with lipoteichoic acid (LTA), another staphylococcal microbial-associated molecular pattern (MAMP). MDP induced a prompt and marked influx of neutrophils in milk, and its combination with LTA elicited a more intense and prolonged influx than the responses to either stimulus alone. The concentrations of several chemoattractants for neutrophils (CXCL1, CXCL2, CXCL3, CXCL8, and C5a) increased in milk after challenge, and the highest increases followed challenge with the combination of MDP and LTA. MDP and LTA were also synergistic in inducing in vitro chemokine production by bovine mammary epithelial cells (bMEpC). Nucleotide-binding oligomerization domain 2 (NOD2), a major sensor of MDP, was expressed (mRNA) in bovine mammary tissue and by bMEpC in culture. The production of interleukin-8 (IL-8) following the stimulation of bMEpC by LTA and MDP was dependent on the activation of NF-?B. LTA-induced IL-8 production did not depend on platelet-activating factor receptor (PAFR), as the PAFR antagonist WEB2086 was without effect. In contrast, bMEpC and mammary tissue are known to express Toll-like receptor 2 (TLR2) and to respond to TLR2 agonists. Although the levels of expression of the inflammatory cytokines tumor necrosis factor alpha (TNF-?) and IL-1? were increased by LTA and MDP at the mRNA level, no protein could be detected in the bMEpC culture supernatant. The level of induction of IL-6 was low at both the mRNA and protein levels. These results indicate that MDP and LTA exert synergistic effects to induce neutrophilic inflammation in the mammary gland. These results also show that bMEpC could contribute to the inflammatory response by recognizing LTA and MDP and secreting chemokines but not proinflammatory cytokines. Overall, this study indicates that the TLR2 and NOD2 pathways could cooperate to trigger an innate immune response to S. aureus mastitis. PMID:20826612

Bougarn, Salim; Cunha, Patricia; Harmache, Abdallah; Fromageau, Angélina; Gilbert, Florence B; Rainard, Pascal



Dipeptide frequency/bias analysis identifies conserved sites of nonrandomness shared by cysteine-rich motifs.  


This report describes the application of a simple computational tool, AAPAIR.TAB, for the systematic analysis of the cysteine-rich EGF, Sushi, and Laminin motif/sequence families at the two-amino acid level. Automated dipeptide frequency/bias analysis detects preferences in the distribution of amino acids in established protein families, by determining which "ordered dipeptides" occur most frequently in comprehensive motif-specific sequence data sets. Graphic display of the dipeptide frequency/bias data revealed family-specific preferences for certain dipeptides, but more importantly detected a shared preference for employment of the ordered dipeptides Gly-Tyr (GY) and Gly-Phe (GF) in all three protein families. The dipeptide Asn-Gly (NG) also exhibited high-frequency and bias in the EGF and Sushi motif families, whereas Asn-Thr (NT) was distinguished in the Laminin family. Evaluation of the distribution of dipeptides identified by frequency/bias analysis subsequently revealed the highly restricted localization of the G(F/Y) and N(G/T) sequence elements at two separate sites of extreme conservation in the consensus sequence of all three sequence families. The similar employment of the high-frequency/bias dipeptides in three distinct protein sequence families was further correlated with the concurrence of these shared molecular determinants at similar positions within the distinctive scaffolds of three structurally divergent, but similarly employed, motif modules. PMID:11455605

Campion, S R; Ameen, A S; Lai, L; King, J M; Munzenmaier, T N



The hydrolysis by thermolysin of dipeptide derivatives that contain substituted cysteine  

PubMed Central

1. The preparation of protected dipeptides of the form acetylglycylamino acid amides is described, where the amino acid is phenylalanine, leucine, valine, alanine, S-methylcysteine, S-ethylcysteine, S-benzylcysteine and S-phenylcysteine. 2. Kinetic parameters for the thermolytic hydrolysis of these blocked dipeptides are reported. The rate of hydrolysis was fastest when the amino acid was leucine or phenylalanine, slower when it was S-methylcysteine, valine or S-ethylcysteine, much slower when it was alanine, and negligible for S-phenylcysteine or S-benzylcysteine. 3. The results are compared with those for similar dipeptide derivatives with benzyloxycarbonyl and furylacryloyl blocking groups, which are hydrolysed faster.

Damoglou, A. P.; Lindley, H.; Stapleton, I. W.



Surface nucleated growth of dipeptide fibres.  


We report the surface nucleated growth of self-assembled dipeptide films. The seeding-layer was a thin dipeptide film with a globular structure. Placing the seeding-layer in contact with dipeptide led to growth of fibres overnight. Active enzymes were incorporated into the gel by adding them to the growth solution. PMID:23955276

Johnson, Eleanor K; Chen, Lin; Kubiak, Peter S; McDonald, Shane F; Adams, Dave J; Cameron, Petra J



Nearest-Neighbor Interactions and Their Influence on the Structural Aspects of Dipeptides  

PubMed Central

In this theoretical study, the role of the side chain moiety of C-terminal residue in influencing the structural and molecular properties of dipeptides is analyzed by considering a series of seven dipeptides. The C-terminal positions of the dipeptides are varied with seven different amino acid residues, namely. Val, Leu, Asp, Ser, Gln, His, and Pyl while their N-terminal positions are kept constant with Sec residues. Full geometry optimization and vibrational frequency calculations are carried out at B3LYP/6-311++G(d,p) level in gas and aqueous phase. The stereo-electronic effects of the side chain moieties of C-terminal residues are found to influence the values of ? and ? dihedrals, planarity of the peptide planes, and geometry around the C7?? ?-carbon atoms of the dipeptides. The gas phase intramolecular H-bond combinations of the dipeptides are similar to those in aqueous phase. The theoretical vibrational spectra of the dipeptides reflect the nature of intramolecular H-bonds existing in the dipeptide structures. Solvation effects of aqueous environment are evident on the geometrical parameters related to the amide planes, dipole moments, HOMOLUMO energy gaps as well as thermodynamic stability of the dipeptides.

Das, Gunajyoti; Mandal, Shilpi



Hydroxyapatite–collagen–hyaluronic acid composite  

Microsoft Academic Search

The new composite biomaterial made from hydroxyapatite and collagen conjugated with hyaluronic acid has been studied. The structure evaluation of the composite showed more dense arrangement due to the formation of collagen–hyaluronic acid conjugate, and particles of inorganic component are closely anchored in the structure. Mechanical properties and model swelling of this composite are compared with properties of hydroxyapatite–collagen composite

D. Bakoš; M. Soldán; I. Hernández-Fuentes



Well acidizing compositions and method  

SciTech Connect

This patent describes a concentrate which forms an acid internal microemulsion well treatment composition when added to an acid treatment fluid. It comprises in the range of from about 20% to about 98% by weight of a hydrocarbon carrier fluid; in the range of from about 1% to about 50% by weight of an alkyl alcohol having in the range of from about 4 to 18 carbon atoms; and in the range of from about 1% to about 50% by weight of an emulsifying agent comprising at least one compound selected from the group consisting of amine salts having ester or amide linkages and propoxylated alcohols, each of the components being different compounds or different mixtures of compounds.

Gardener, T.R.; Dill, W.R.; Ford, W.G.F.; King, K.L.



Self-assembled nanoparticles based on modified cationic dipeptides and DNA: novel systems for gene delivery  

PubMed Central

Background Gene therapy is most effective when delivery is both efficient and safe. However, it has often proven difficult to find a balance between efficiency and safety in case of viral or polymeric vectors for gene therapy. Peptide based delivery systems may be attractive alternatives but their relative instability to proteolysis is a major concern in realizing their potential application in biomedical sciences. In this work we report gene delivery potential of nanoparticles (Nps) synthesized from cationic dipeptides containing a non-protein amino acid ?, ?-dehydrophenylalanine (?Phe) residue. Methods Dipeptides were synthesized using solution phase peptide synthesis method. Nps were formed using self-assembly. Nps were characterized using light scattering, electron microscopy. Transfection efficiency was tested in hepatocellular carcinoma (HuH 7) cells. Results The cationic dipeptides condensed plasmid DNA into discrete vesicular nanostructures. Dipeptide Nps are non-cytotoxic, protected the condensed DNAs from enzymatic degradation and ferried them successfully inside different types of cells. GFP encoding plasmid DNA loaded dipeptide Nps showed positive transfection and gene expression in HuH 7 cells. Conclusions The cationic dipeptide Nps can successfully deliver DNA without exerting any cytotoxic effect. Owing to their simple dipeptide origin, ease of synthesis, enhanced enzymatic stability as well unmatched biocompatibility, these could be successfully developed as vehicles for effective gene therapy.



A comprehensive library of blocked dipeptides reveals intrinsic backbone conformational propensities of unfolded proteins.  


Despite prolonged scientific efforts to elucidate the intrinsic peptide backbone preferences of amino-acids based on understanding of intermolecular forces, many open questions remain, particularly concerning neighboring peptide interaction effects on the backbone conformational distribution of short peptides and unfolded proteins. Here, we show that spectroscopic studies of a complete library of 400 dipeptides reveal that, irrespective of side-chain properties, the backbone conformation distribution is narrow and they adopt polyproline II and ?-strand, indicating the importance of backbone peptide solvation and electronic effects. By directly comparing the dipeptide circular dichroism and NMR results with those of unfolded proteins, the comprehensive dipeptides form a complete set of structural motifs of unfolded proteins. We thus anticipate that the present dipeptide library with spectroscopic data can serve as a useful database for understanding the nature of unfolded protein structures and for further refinements of molecular mechanical parameters. PMID:22223291

Oh, Kwang-Im; Lee, Kyung-Koo; Park, Eun-Kyung; Jung, Youngae; Hwang, Geum-Sook; Cho, Minhaeng



The discovery of sulfonylated dipeptides as Potent VLA4 antagonists  

Microsoft Academic Search

Directed screening of a carboxylic acid-containing combinatorial library led to the discovery of potent inhibitors of the integrin VLA-4. Subsequent optimization by solid-phase synthesis afforded a series of sulfonylated dipeptide inhibitors with structural components that when combined in a single hybrid molecule gave a sub-nanomolar inhibitor as a lead for medicinal chemistry. Preliminary metabolic studies led to the discovery of

William K Hagmann; Philippe L Durette; Thomas Lanza; Nancy Jo Kevin; Stephen E de Laszlo; Ihor E Kopka; David Young; Plato A Magriotis; Bing Li; Linus S Lin; Ginger Yang; Theodore Kamenecka; Linda L Chang; Jonathan Wilson; Malcolm MacCoss; Sander G Mills; Gail Van Riper; Ermengilda McCauley; Linda A Egger; Usha Kidambi; Kathryn Lyons; Stella Vincent; Ralph Stearns; Adria Colletti; Johannes Teffera; Sharon Tong; Judy Fenyk-Melody; Karen Owens; Dorothy Levorse; Philip Kim; John A Schmidt; Richard A Mumford



Amino Acid Composition of Germinating Cotton Seeds  

PubMed Central

Total and free amino acid composition of germinating cotton seeds (Gossypium hirsutum L.) was determined. The germinating seeds were separated into cotyledon and developing axis fractions daily and the composition of each tissue was summed to get the whole seed composition. By separating the developing seeds into these two tissue fractions, and determining total and free amino acids, a balance sheet was developed for each amino acid. This technique allowed changes in distribution with time of each amino acid to be followed in each tissue. Data for total content and amount in protein of each amino acid are presented. Asparagine increased in the whole seed, and most of this increase was found in the free pool of the developing axis. Other amino acids (e.g. arginine, glutamic acid) increased in the free pool but showed an over-all decrease, indicating that they were being metabolized. Amino acid contents of storage and nonstorage protein isolates were determined.

Elmore, C. Dennis; King, Earl E.



Composition for nucleic acid sequencing  


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 followed in real time. The sequence is deduced by identifying which base is being incorporated into the growing complementary strand of the target nucleic acid by the catalytic activity of the nucleic acid polymerizing enzyme at each step in the sequence of base additions. A polymerase on the target nucleic acid molecule complex is provided in a position suitable to move along the target nucleic acid molecule and extend the oligonucleotide primer at an active site. A plurality of labelled types of nucleotide analogs are provided proximate to the active site, with each distinguishable type of nucleotide analog being complementary to a different nucleotide in the target nucleic acid sequence. The growing nucleic acid strand is extended by using the polymerase to add a nucleotide analog to the nucleic acid strand at the active site, where the nucleotide analog being added is complementary to the nucleotide of the target nucleic acid at the active site. The nucleotide analog added to the oligonucleotide primer as a result of the polymerizing step is identified. The steps of providing labelled nucleotide analogs, polymerizing the growing nucleic acid strand, and identifying the added nucleotide analog are repeated so that the nucleic acid strand is further extended and the sequence of the target nucleic acid is determined.

Korlach, Jonas (Ithaca, NY); Webb, Watt W. (Ithaca, NY); Levene, Michael (Ithaca, NY); Turner, Stephen (Ithaca, NY); Craighead, Harold G. (Ithaca, NY); Foquet, Mathieu (Ithaca, NY)



Amino acid composition of some Mexican foods.  


Knowledge of the amino acid composition of foods is essential to calculate their chemical score, which is used to predict protein quality of foods and diets. Though amino acid composition of many foods is reasonably well established, better knowledge is needed on native foods consumed in different regions and countries. This paper presents the amino acid composition of different presentations of raw and processed foods produced and consumed in Mexico. The amino acid composition was determined using Beckman amino acid analyzers (models 116 and 6300). Tryptophan was determined using the Spies and Chambers method. Of the different foods analyzed, some comments are made on native or basic foods in Mexico: Spirulin, where lysine is the limiting amino acid, with a chemical score of 67%, is a good source of tryptophan (1.16g/16 gN); amaranth contains high levels of sulphur amino acids (4.09 to 5.34 g/16gN), with a protein content of 15 g/100g; and pulque, a Pre-Hispanic beverage that contains high levels of tryptophan (2.58 g/16 gN) and sulphur amino acids (2.72 g/16 gN). Finally, insects are good sources of sulphur amino acids and lysine. PMID:16335228

Morales de León, Josefina; Camacho, M Elena; Bourges, Héctor



Relationships between mucosal hydrolysis and transport of two phenylalanine dipeptides.  

PubMed Central

In order to investigate the source of free amino acids found in the gut lumen during absorption of dipeptides, as well as evaluating the role of brush border peptidases in the mucosal hydrolysis of dipeptides during absorption, rates of dipeptide disappearance and appearance of hydrolytic products were measured during perfusion of rat jejunum and ileum in vivo with buffered and unbuffered 10 mM solutions of glycl-L-phenylalanine (Gly-Phe) and L-phenylalanyl-glycine (Phe-Gly). Mucosal brush border peptidase activity was then measured in the perfused segments in vitro at luminal pH and at two substrate concentrations. In addition cytosol peptidase activity in the perfused segments was measured at pH 7-4 and at 10 mM substrate concentrations. In the jejunum, there was a relationship between rates of free phenylalanine appearance in vivo (Phe-Gly greater than Gly-Phe) and rates of brush border (Phe-Gly greater than Gly-Phe) rather than cytosol (Gly-Phe greater than Phe-Gly) peptidase activities. No constant relationship between free phenylalanine appearance and hydrolysis of the dipeptides by either brush border or cytosol peptidases was observed in the ileal studies. These findings suggest that, in the jejunum, hydrolytic products originate from the surface of the cell whereas, in the ileum, hydrolytic products originate from both the intracellular compartment as well as from the surface of the mucosal cell. In the jejunum, in vitro rates of brush border hydrolysis of Gly-Phe were always less than in vivo disappearance rates, whereas rates of Phe-Gly brush border hydrolysis always exceeded luminal disappearance rates. These data imply that Gly-Phe is predominantly transported intact and hydrolysed by cytosol peptidases, In contrast, brush border peptidases play an importnat role in the mucosal hydrolysis of Phe-Gly.

Silk, D B; Nicholson, J A; Kim, Y S



Method and composition for acidizing subterranean formations  

SciTech Connect

The present invention relates to a method of acidizing a subterranean formation or well bore employing an acidic solution containing a stabilized corrosion inhibitor composition comprising an inhibiting effective amount of an acetylenic alcohol, a quaternary ammonium compound, an aromatic hydrocarbon, an antimony compound, and a stabilizer which substantially prevents precipitation of solubilized antimony-containing compounds from aqueous solutions.

Walker, M. L.



Method and composition for acidizing subterranean formations  

SciTech Connect

The present invention relates to a method of acidizing a subterranean formation or well bore employing an acidic solution containing a corrosion inhibitor composition comprising an inhibiting effective amount of an acetylenic alcohol, a quaternary ammonium compound, an aromatic hydrocarbon and an antimony compound.

Walker, M. L.



Antimicrobial activity of selected cyclic dipeptides.  


Cyclic dipeptides are products of rational drug design, which may exhibit both antimicrobial and antitumor properties. The aim of this study was to investigate both the antimicrobial effects of the cyclic dipeptides cyclo(L-phenylalanyl-L-prolyl), cyclo(L-tyrosyl-L-prolyl), cyclo(L-tryptophanyl-L-prolyl) and cyclo(L-tryptophanyl-L-tryptophanyl) and the effects of these cyclic dipeptides on the gastrointestinal epithelium in vitro. Furthermore, a relevant solvent for the possible pharmaceutical application of the products was sought concurrently. The antimicrobial effect of the cyclic dipeptides was assayed using the Kirby-Bauer disc diffusion assay against Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphylococcus aureus, Bacillus subtilis, Streptococcus pneumoniae, Candida albicans, Aspergillus niger and Penicillium notatum. The effect of the cyclic dipeptides on the gastrointestinal epithelium was assessed by changes in alkaline phosphatase expression of HT-29 cells. Cyclo(Pro-Trp) and cyclo(Phe-Pro) show broad spectrum antibacterial properties and cyclo(Trp-Pro) and cyclo(Trp-Trp) show broad spectrum antifungal properties. The maturation of the gastrointestinal cells was enhanced by cyclo(Phe-Pro), cyclo(Tyr-Pro), cyclo(Trp-Trp) and cyclo(Trp-Pro). The activity of these cyclic dipeptides thus indicates potential application of these compounds as pharmacological agents. PMID:10563376

Graz, M; Hunt, A; Jamie, H; Grant, G; Milne, P



Thermodynamic properties of peptide solutions: 7. Partial molar isentropic pressure coefficients of some dipeptides in aqueous solution  

Microsoft Academic Search

The partial molar isentropic pressure coefficients at infinite dilution, KS,2o, have been determined for a number of dipeptides in aqueous solution at 25°C. For a series of dipeptides of sequence gly-X, where X is an amino acid with a neutral side chain, the KS,2o values are all more negative than that for diglycine. The results are discussed in terms of

Gavin R. Hedwig; Harald Høiland



Chemical composition of acid fog  

Microsoft Academic Search

Fog water collected at three sites in Los Angeles and Bakersfield, California, was found to have higher acidity and higher concentrations of sulfate, nitrate, and ammonium than previously observed in atmospheric water droplets. The pH of the fog water was in the range of 2.2 to 4.0. the dominant processes controlling the fog water chemistry appear to be the condensation

J. M. Waldman; J. W. Munger; D. J. Jacob; R. C. Flagan; J. J. Morgan; M. R. Hoffmann



The fatty acid composition of human colostrum  

Microsoft Academic Search

Summary   We reviewed 15 studies reporting on the fatty acid composition of colostrum lipids from 16 geographic regions: 11 European\\u000a studies and one study each from Central America, the Caribbean, Australia and Asia. The contents of essential fatty acids,\\u000a saturates and polyunsaturates were similar in the southern European countries Spain, Slovenia and France. Colostrum of St.\\u000a Lucian women was high

Natasa Fidler; Berthold Koletzko



Microporous organic materials from hydrophobic dipeptides.  


In the last few years dipeptides with two hydrophobic residues (hydrophobic dipeptides) have emerged as an unexpected source of stable microporous organic materials. Supramolecular self-assembly of the rather small building blocks is dictated by stringent demands on the hydrogen-bond formation by the peptide main chains and the aggregation of hydrophobic entities in the side chains. A systematic survey of structures derived from single-crystal X-ray diffraction studies has revealed the existence of two large classes of structures, differing in the dimensionality of the hydrogen-bonding patterns in the crystals and the nature of the channels. The present review summarizes the structural properties of the microporous dipeptides and discusses their potential applications. PMID:17200919

Görbitz, Carl Henrik



The amino acid composition of mammalian and bacterial cells  

Microsoft Academic Search

Summary High performance liquid chromatography was used to analyze the amino acid composition of cells. A total of 17 amino acids was analyzed. This method was used to compare the amino acid compositions of the following combinations: primary culture and established cells, normal and transformed cells, mammalian and bacterial cells, andEscherichia coli andStaphylococcus aureus. The amino acid compositions of mammalian

T. Okayasu; M. Ikeda; K. Akimoto; K. Sorimachi



Nitrogen15 NMR studies of solid dipeptides  

Microsoft Academic Search

The first part of this study deals with the systematic determination of the ¹⁵N chemical shift tensor for the series of dipeptides N-acetyl(1-¹³C)-glycyl-(¹⁵N)-X-amide (GlyX: X = alanine, glycine, tyrosine), (1-¹³C)-glycyl(¹⁵N)-glycine\\/center dot\\/HCL and (1-¹³C)-ananyl-(¹⁵N)-alanine (AlaAla). The principal values and polar angles relating the chemical shift tensor to the peptide C-N bond are given for all dipeptides studied. The isotropic values for




Using pseudo amino acid composition to predict protein subcellular location: approached with amino acid composition distribution  

Microsoft Academic Search

Summary.  In the Post Genome Age, there is an urgent need to develop the reliable and effective computational methods to predict the\\u000a subcellular localization for the explosion of newly found proteins. Here, a novel method of pseudo amino acid (PseAA) composition,\\u000a the so-called “amino acid composition distribution” (AACD), is introduced. First, a protein sequence is divided equally into\\u000a multiple segments. Then,

J.-Y. Shi; S.-W. Zhang; Q. Pan; G.-P. Zhou



Cellular Fatty Acid Compositions of Moraxella anatipestifer and Legionella pneumophila  

Microsoft Academic Search

In contrast to results from a recent study, we found the fatty acid composition of Legionella pneumophila to be distinct from the fatty acid composition of Moraxella anatipestifer. M. anatipestifer contained large amounts (50%) of 13-methyltetradecanoic acid and smaller amounts (5 to 22%) of branched-chain hydroxy acids, whereas L. pneumophila contained 14-methylpentadecanoic acid as the major component (30%), with no



Ocular Sustained Release Nanoparticles Containing Stereoisomeric Dipeptide Prodrugs of Acyclovir  

PubMed Central

Abstract Purpose The objective of this study was to develop and characterize polymeric nanoparticles of appropriate stereoisomeric dipeptide prodrugs of acyclovir (L-valine-L-valine-ACV, L-valine-D-valine-ACV, D-valine-L-valine-ACV, and D-valine-D-valine-ACV) for the treatment of ocular herpes keratitis. Methods Stereoisomeric dipeptide prodrugs of acyclovir (ACV) were screened for bioreversion in various ocular tissues, cell proliferation, and uptake across the rabbit primary corneal epithelial cell line. Docking studies were carried out to examine the affinity of prodrugs to the peptide transporter protein. Prodrugs with optimum characteristics were selected for the preparation of nanoparticles using various grades of poly (lactic-co-glycolic acid) (PLGA). Nanoparticles were characterized for the entrapment efficiency, surface morphology, size distribution, and in vitro release. Further, the effect of thermosensitive gels on the release of prodrugs from nanoparticles was also studied. Results L-valine-L-valine-ACV and L-valine-D-valine-ACV were considered to be optimum in terms of enzymatic stability, uptake, and cytotoxicity. Docking results indicated that L-valine in the terminal position increases the affinity of the prodrugs to the peptide transporter protein. Entrapment efficiency values of L-valine-L-valine-ACV and L-valine-D-valine-ACV were found to be optimal with PLGA 75:25 and PLGA 65:35 polymers, respectively. In vitro release of prodrugs from nanoparticles exhibited a biphasic release behavior with initial burst phase followed by sustained release. Dispersion of nanoparticles in thermosensitive gels completely eliminated the burst release phase. Conclusion Novel nanoparticulate systems of dipeptide prodrugs of ACV suspended in thermosensitive gels may provide sustained delivery after topical administration.

Jwala, Jwala; Boddu, Sai H.S.; Shah, Sujay; Sirimulla, Suman; Pal, Dhananjay



Method and compositions for acidizing and fracturing wells  

SciTech Connect

Gelled-acid compositions suitable for matrix-acidizing or fracture-acidizing of subterranean formations and methods of using the composition in these operations are provided wherein the compositions comprise water, water-dispersible acrylamide-derived polymer, an acid and an aldehyde precursor which hydrolyzes in aqueous acid media to produce aldehydes which in turn react with the polymer and gels the resulting mixture.

Josephson, C. B.



Method of and composition for acidizing subterranean formations  

Microsoft Academic Search

A composition and method for acid treating a subterranean formation are described. It has been discovered that the addition of various chemical additives such as formic acid, or acetic acid or the alkali metal or ammonium salt of formic acid or acetic acid, or hexamethylenetetramine (HMTA) will slow the rate of formation of a free acid when an aldehyde reacts




Dietary fat and the fatty acid composition of tissue lipids  

Microsoft Academic Search

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

K. K. Carroll



Amino Acid Composition and Terminal Amino Acids of Staphylococcal Enterotoxin B.  

National Technical Information Service (NTIS)

The amino acid composition of purified staphylococcal enterotoxin B was determined by means of an automatic amino acid analyzer. All of the naturally occurring amino acids were found with no indication of any unusual amino acids. Extraordinarily high valu...

L. Spero D. Stefanye P. I. Brecher H. M. Jacoby E. J. Schantz



Mechanism of action of anticandidal dipeptides containing inhibitors of glucosamine-6-phosphate synthase.  

PubMed Central

The mechanism of anticandidal action of novel synthetic dipeptides containing N3-(4-methoxyfumaroyl)-L-2,3-diaminopropanoic acid (FMDP) residues was shown to be consistent with the "warhead delivery" concept. FMDP dipeptides were shown to be transported into Candida albicans cells by the di-tripeptide permease and subsequently hydrolyzed by intracellular peptidases, especially aminopeptidase. The anticandidal activity of the particular FMDP dipeptide was influenced by the rate of its transport and, to a lower extent, by the intracellular cleavage rate. A high transport rate accompanied by a high cleavage rate resulted in the high anticandidal activity of L-norvalyl-FMDP. The strong growth-inhibitory effect of this compound was the consequence of inhibition of the enzyme glucosamine-6-phosphate synthase by the released FMDP. The action of L-norvalyl-FMDP on exponentially growing C. albicans cells resulted in a sharp decrease of incorporation of 14C label from [14C]glucose into chitin, mannoprotein, and glucan. This effect, as well as the growth-inhibitory effect, was fully reversed by exogenous N-acetyl-D-glucosamine. Glucosamine-6-phosphate synthase was proved to be the only essential target for FMDP dipeptides. Scanning electron microscopy of C. albicans cells treated with L-norvalyl-FMDP revealed highly distorted, wrinkled, and collapsed forms. Cells formed long, bulbous chains, and partial lysis occurred. Images

Milewski, S; Andruszkiewicz, R; Kasprzak, L; Mazerski, J; Mignini, F; Borowski, E



Fatty acid composition of 15 species of marine microalgae  

Microsoft Academic Search

The fatty acid composition of 15 marine microalgal species, belonging to the Chlorophyceae, Prasinophyceae, Bacillariophyceae, Prymnesiophyceae, Dinophyceae, Eustigmatophyceae, Crytophyceae, Rhodophyceae, and cultured under comparable conditions has been studied. It is shown that each class of microalgae is characterized by a specific fatty acid profile. It is proposed that uncommon acids, some typical acids and the ratio of acids are useful

Natalia V. Zhukova; Nina A. Aizdaicher



Human Blood-Brain Differential Gene-Expression Correlates with Dipeptide Frequency of Gene Products  

Microsoft Academic Search

Differential gene expression in different tissues is largely considered to be the specific property of individual genes. In\\u000a this work a relationship between overall dipeptide composition of proteins encoded by genes on the one hand and the difference\\u000a in their expression level in two of the most important human organs i. e. blood and brain have been studied. Study is

Shandar Ahmad



Amino Acid Composition of Crystalline Botulinum Toxin, Type A.  

National Technical Information Service (NTIS)

The amino acid composition of botulinum toxin, type A, was determined with the aid of the automatic amino acid analyzer. The results are compared with an earlier largely microbiological analysis. (Author)

D. Stefanye



Nonenzymatic glycosylation of the dipeptide l-carnosine, a potential anti-protein-cross-linking agent  

Microsoft Academic Search

The dipeptide carnosine (?-alanyl-l-histidine) was readily glycosylated non-enzymatically upon incubation with the sugars glucose, galactose, deoxyribose and the triose dihydroxyacetone. Carnosine inhibited glycation of actyl-Lys-His-amide by dihydroxyacetone and it protected ?-crystallin, superoxide dismutase and catalise against glycation and cross-linking mediated by ribose, deoxyribose, dihydroxyacetone, dihydroxyacetone phosphate and fructose. Unlike certain glycated amino acids, glycated carnosine was non-mutagenic. The potential biological

Alan R. Hipkiss; Jürgen Michaelis; Petros Syrris



Evolutionary changes reflected by the cellular amino acid composition  

Microsoft Academic Search

Summary Comparison of the amino acid composition of cell-proteins using 17 amino acids has been used to investigate the biological evolution of organisms such as bacteria, blue-green alga, green alga, fungi, slime mold, protozoa and vertebrates. The degree of difference in the amino acid ratios between any two groups reflects the degree of divergency in biological evolution. The amino acid

K. Sorimachi



Effect of diet on fatty acid compositions in Sciaenops ocellatus  

Microsoft Academic Search

The role of dietary polyunsaturated fatty acids (PUFAs) on the fatty acid composition of juvenile red drum Sciaenops ocellatus was investigated. Individuals (n ¼ 435) were fed three natural diets (Gulf menhaden Brevoortia patronus, brown shrimp Farfantapenaeus aztecus and Atlantic brief squid Lolliguncula brevis) that had significantly different proximate composi- tion, energy density and PUFA compositions for 40 days. Diets




Self-assembly and gelation properties of glycine/leucine Fmoc-dipeptides.  


Self-assembly of aromatic peptide amphiphiles is known to be driven by a combination of ?-? stacking of the aromatic moieties and hydrogen bonding between the peptide backbones, with possible stabilisation from the amino acid side chains. Phenylalanine-based Fmoc-dipeptides have previously been reported for their characteristic apparent pKa transitions, which were shown to coincide with significant structural and morphological changes that were peptide sequence dependent. Here, phenylalanine was replaced by leucine and the effect on the self-assembling behaviour of Fmoc-dipeptides was measured using potentiometry, fluorescence and infrared spectroscopy, transmission electron microscopy, X-ray scattering and shear rheometry. This study provides additional cues towards the elucidation of the sequence-structure relationship in self-assembling aromatic peptide amphiphiles. PMID:24085660

Tang, Claire; Ulijn, Rein V; Saiani, Alberto



[Identification of a functionally important dipeptide in sequences of atypical opioid peptides].  


The occurrence of individual amino acids and dipeptide fragments in the sequences of 60 known atypical opioid peptides was analyzed. An expressed predominance of Tyr-Pro fragment suggested a high probability of analgesic activity for this dipeptide, and it was experimentally studied. It was shown on somatic and visceral pain sensitivity models that, on the i.p. administration of Tyr-Pro at doses of 1.0-10 mg/kg of body mass, it exhibits an analgesic activity eliminated by naloxone and naloxone methiodide. However, in tests on ileum preparations of guinea pig and mouse vas deferens in vitro, Tyr-Pro was devoid of opioid activity, which proved its indirect influence on opioid receptors. PMID:19060934

Guzevatykh, L S


Fluosilicate solubilities affect HF acid compositions  

SciTech Connect

The purpose of this work was to determine the solubilities of sodium and potassium fluosilicate over a broad range of HCl concentrations, ionic strengths, and temperatures. These data were required for determining optimum or safe HCl/HF treating-fluid compositions for acidizing sandstone formations containing feldspars. Solubilities of sodium and potassium fluosilicate were determined over a temperature range of 150 to 300 F. Analysis of the solubility data indicated that the solids formed were not simply Na[sub 2]SiF[sub 6] and K[sub 2]SiF[sub 6]. Regression analyses indicated that the sodium salt could best be described as NaHSiF[sub 6] [center dot] 0.52HCl. Regression analyses indicated that the potassium salt could best be described as KHSiF[sub 6] [center dot] 0.41 KCl. The solubility data were then included in a HF-spending simulator to determine regions where possible precipitation of the fluosilicates could occur. Optimum HCl/HF concentrations were then determined for specific mineral and temperature conditions.

Gdanski, R.D. (Halliburton Services Research Center, Duncan, OK (United States). Stimulation Research and Engineering Dept.)



Altered fatty acid desaturation and microsomal fatty acid composition in the streptozotocin diabetic rat  

Microsoft Academic Search

Streptozotocin diabetes in the rat diminishes the synthesis of both monounsaturated and polyunsaturated fatty acids. Rat liver\\u000a microsomal fatty acid composition and fatty acid desaturation were studied in the streptozotocin diabetic rat. The major alterations\\u000a in fatty acid composition found in the diabetic rat were decreased proportions of palmitoleic, oleic and arachidonic acids\\u000a and an increased proportion of linoleic and

Fred H. Faas; William J. Carter



Amino acid composition in Isoparorchis hypselobagri  

Microsoft Academic Search

Summary The free amino acids of Isoparorchis hypselobagri have been determined by the chromatographic method (two-dimensional ascending). These are: leucine, valine, proline, alanine, glycine, glutamic acid and aspartic acid.

Meenakshi Srivastava; S. P. Gupta



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

PubMed Central

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.

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



Fatty acid composition of Costa Rican foods including trans fatty acid content  

Microsoft Academic Search

To further understand the fatty acid–disease relationships in an epidemiologic context, detailed composition tables are required. The composition of the major saturated, monounsaturated, and polyunsaturated fatty acids that are most abundant in the diet, is available for numerous foods in many countries, but data on the content of individual fatty acids with relative low abundance are scarce. We conducted a

Ana Baylin; Xinia Siles; Amy Donovan-Palmer; Xinia Fernandez; Hannia Campos



Organic acids and sugars composition of harvested pomegranate fruits  

Microsoft Academic Search

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

Pablo Melgarejo; Domingo Manuel Salazar; F. Artés



Fatty acid composition of two Athamanta turbith subspecies  

Microsoft Academic Search

The fruit oils of Athamanta turbith ssp. hungarica and Athamanta turbith ssp. haynaldii were obtained by Soxhlet extraction using petroleum ether. The fatty acid composition of oils was determined by GC in the\\u000a methyl ester form. Considering the composition and content of fatty acids, the examined oils were very similar. Petroselinic\\u000a acid was the principal one (45.6 and 46.2%, respectively),

A. Tomic; S. Petrovic; M. Pucarevic; S. Sobajic; M. Ristic; M. Niketic



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


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

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



Fatty acid composition of wild anthropoid primate milks  

Microsoft Academic Search

Fatty acids in milk reflect the interplay between species-specific physiological mechanisms and maternal diet. Anthropoid primates (apes, Old and New World monkeys) vary in patterns of growth and development and dietary strategies. Milk fatty acid profiles also are predicted to vary widely. This study investigates milk fatty acid composition of five wild anthropoids (Alouatta palliata, Callithrix jacchus, Gorilla beringei beringei,

Lauren A. Milligan; Stanley I. Rapoport; Michael R. Cranfield; Wolfgang Dittus; Kenneth E. Glander; Olav T. Oftedal; Michael L. Power; Christopher A. Whittier; Richard P. Bazinet



Soil amino acid composition across a boreal forest successional sequence  

Microsoft Academic Search

Soil amino acids are important sources of organic nitrogen for plant nutrition, yet few studies have examined which amino acids are most prevalent in the soil. In this study, we examined the composition, concentration, and seasonal patterns of soil amino acids across a primary successional sequence encompassing a natural gradient of plant productivity and soil physicochemical characteristics. Soil was collected

Nancy R. Werdin-Pfisterer; Knut Kielland; Richard D. Boone



Amino acid composition of proteins reduces deleterious impact of mutations.  


The evolutionary origin of amino acid occurrence frequencies in proteins (composition) is not yet fully understood. We suggest that protein composition works alongside the genetic code to minimize impact of mutations on protein structure. First, we propose a novel method for estimating thermodynamic stability of proteins whose sequence is constrained to a fixed composition. Second, we quantify the average deleterious impact of substituting one amino acid with another. Natural proteome compositions are special in at least two ways: 1) Natural compositions do not generate more stable proteins than the average random composition, however, they result in proteins that are less susceptible to damage from mutations. 2) Natural proteome compositions that result in more stable proteins (i.e. those of thermophiles) are also tuned to have a higher tolerance for mutations. This is consistent with the observation that environmental factors selecting for more stable proteins also enhance the deleterious impact of mutations. PMID:24108121

Hormoz, Sahand



Amino acid composition of proteins reduces deleterious impact of mutations  

NASA Astrophysics Data System (ADS)

The evolutionary origin of amino acid occurrence frequencies in proteins (composition) is not yet fully understood. We suggest that protein composition works alongside the genetic code to minimize impact of mutations on protein structure. First, we propose a novel method for estimating thermodynamic stability of proteins whose sequence is constrained to a fixed composition. Second, we quantify the average deleterious impact of substituting one amino acid with another. Natural proteome compositions are special in at least two ways: 1) Natural compositions do not generate more stable proteins than the average random composition, however, they result in proteins that are less susceptible to damage from mutations. 2) Natural proteome compositions that result in more stable proteins (i.e. those of thermophiles) are also tuned to have a higher tolerance for mutations. This is consistent with the observation that environmental factors selecting for more stable proteins also enhance the deleterious impact of mutations.

Hormoz, Sahand



Amino acid composition of proteins reduces deleterious impact of mutations  

PubMed Central

The evolutionary origin of amino acid occurrence frequencies in proteins (composition) is not yet fully understood. We suggest that protein composition works alongside the genetic code to minimize impact of mutations on protein structure. First, we propose a novel method for estimating thermodynamic stability of proteins whose sequence is constrained to a fixed composition. Second, we quantify the average deleterious impact of substituting one amino acid with another. Natural proteome compositions are special in at least two ways: 1) Natural compositions do not generate more stable proteins than the average random composition, however, they result in proteins that are less susceptible to damage from mutations. 2) Natural proteome compositions that result in more stable proteins (i.e. those of thermophiles) are also tuned to have a higher tolerance for mutations. This is consistent with the observation that environmental factors selecting for more stable proteins also enhance the deleterious impact of mutations.

Hormoz, Sahand



Fatty acid compositions of six wild edible mushroom species.  


The fatty acids of six wild edible mushroom species (Boletus reticulatus, Flammulina velutipes var. velutipes, Lactarius salmonicolor, Pleurotus ostreatus, Polyporus squamosus, and Russula anthracina) collected from different regions from Anatolia were determined. The fatty acids were identified and quantified by gas chromatography and studied using fruit bodies. Fatty acid composition varied among species. The dominant fatty acid in fruit bodies of all mushrooms was cis-linoleic acid (18 : 2). Percentage of cis-linoleic acid in species varied from 22.39% to 65.29%. The other major fatty acids were, respectively, cis-oleic, palmitic, and stearic acids. Fatty acids analysis of the mushrooms showed that the unsaturated fatty acids were at higher concentrations than saturated fatty acids. PMID:23844377

Günç Ergönül, Pelin; Akata, Ilgaz; Kalyoncu, Fatih; Ergönül, Bülent



Fatty Acid Compositions of Six Wild Edible Mushroom Species  

PubMed Central

The fatty acids of six wild edible mushroom species (Boletus reticulatus, Flammulina velutipes var. velutipes, Lactarius salmonicolor, Pleurotus ostreatus, Polyporus squamosus, and Russula anthracina) collected from different regions from Anatolia were determined. The fatty acids were identified and quantified by gas chromatography and studied using fruit bodies. Fatty acid composition varied among species. The dominant fatty acid in fruit bodies of all mushrooms was cis-linoleic acid (18?:?2). Percentage of cis-linoleic acid in species varied from 22.39% to 65.29%. The other major fatty acids were, respectively, cis-oleic, palmitic, and stearic acids. Fatty acids analysis of the mushrooms showed that the unsaturated fatty acids were at higher concentrations than saturated fatty acids.

Gunc Ergonul, Pelin; Akata, Ilgaz; Kalyoncu, Fatih; Ergonul, Bulent



Amino acid composition and antioxidant capacity of Spanish honeys.  


The amino acid composition of 53 honey samples from Spain, consisting of 39 floral, 5 honeydew, and 9 blend honeys, has been determined. Physicochemical characteristics, polyphenolic content, amino acid composition, and estimation of the radical scavenging capacity against the stable free radical DPPH of the honey samples were analyzed. The resulting data have been statistically evaluated. The results showed that pH, acidity, net absorbance, electrical conductivity, and total polyphenolic contents of the honeys showed a strong correlation with the radical scavenging capacity. The correlation between the radical scavenging capacity of honey and amino acid contents was high with 18 of the 20 amino acids detected, with correlation values higher than those obtained for polyphenolic content. These results suggest that the amino acid composition of honey is an indicator of the sample's scavenging capacity. PMID:17227066

Pérez, Rosa Ana; Iglesias, María Teresa; Pueyo, Encarnación; Gonzalez, Montserrat; de Lorenzo, Cristina



Mechanism and energetics of dipeptide transport in membrane vesicles of Lactococcus lactis.  

PubMed Central

Alanyl-alpha-glutamate transport has been studied in Lactococcus lactis ML3 cells and in membrane vesicles fused with liposomes containing beefheart cytochrome c oxidase as a proton-motive-force-generating system. The uptake of Ala-Glu observed in de-energized cells can be stimulated 26-fold upon addition of lactose. No intracellular dipeptide pool could be detected in intact cells. In fused membranes, a 40-fold accumulation of Ala-Glu was observed in response to a proton motive force. Addition of ionophores and uncouplers resulted in a rapid efflux of the accumulated dipeptide, indicating that Ala-Glu accumulation is directly coupled to the proton motive force as a driving force. Ala-Glu uptake is an electrogenic process and the dipeptide is transported in symport with two protons. In both fused membranes and intact cells the same affinity constant (0.70 mM) for Ala-Glu uptake was found. Accumulated Ala-Glu is exchangeable with externally added alanyl-glutamate, glutamyl-glutamate, and leucyl-leucine, while no exchange occurred upon addition of the amino acid glutamate or alanine. These results indicate that the Ala-Glu transport system has a broad substrate specificity.

Smid, E J; Driessen, A J; Konings, W N



A molecular dynamics study of the dielectric properties of aqueous solutions of alanine and alanine dipeptide  

NASA Astrophysics Data System (ADS)

Molecular dynamics simulations were used to compute the frequency-dependent dielectric susceptibility of aqueous solutions of alanine and alanine dipeptide. We studied four alanine solutions, ranging in concentration from 0.13-0.55 mol/liter, and two solutions of alanine dipeptide (0.13 and 0.27 mol/liter). In accord with experiment we find a strong dielectric increment for both solutes, whose molecular origin is shown to be the zwitterionic nature of the solutes. The dynamic properties were analyzed based on a dielectric component analysis into solute, a first hydration shell, and all remaining (bulk) waters. The results of this three component decomposition were interpreted directly, as well as by uniting the solute and hydration shell component to a ``suprasolute'' component. In both approaches three contributions to the frequency-dependent dielectric properties can be discerned. The quantitatively largest and fastest component arises from bulk water [i.e., water not influenced by the solute(s)]. The interaction between waters surrounding the solute(s) (the hydration shell) and bulk water molecules leads to a relaxation process occurring on an intermediate time scale. The slowest relaxation process originates from the solute(s) and the interaction of the solute(s) with the first hydration shell and bulk water. The primary importance of the hydration shell is the exchange of shell and bulk waters; the self-contribution from bound water molecules is comparatively small. While in the alanine solutions the solute-water cross-terms are more important than the solute self-term, the solute contribution is larger in the dipeptide solutions. In the latter systems a much clearer separation of time scales between water and alanine dipeptide related properties is observed. The similarities and differences of the dielectric properties of the amino acid/peptide solutions studied in this work and of solutions of mono- and disaccharides and of the protein ubiquitin are discussed.

Boresch, Stefan; Willensdorfer, Martin; Steinhauser, Othmar



Bile acid composition in brown pigment stones.  


The bile acids in brown pigment stones and gallbladder bile were fractionated into free acids, glycine and taurine conjugates, and sulfates using diethylaminohydroxypropyl Sephadex LH-20 (DEAP-LH-20) column chromatography and were quantitated by gas chromatography. Twenty-eight cases of brown pigment stones were studied and divided into two groups: those with and those without bacteria possessing bile acid-deconjugating activity. In the former, free bile acid amounted to 62 +/- 34% of the total bile acid, while in the latter, only 0.1% of total bile acid was free bile acid. The fraction of total bile acid made up of free bile acids was found to be consistently higher in brown pigment stones than in the corresponding bile, irrespective of the presence or absence of biliary infection. Free bile acid is present in negligible amounts in normal bile. Total bile acid concentration in the bile of patients with brown pigment stones was significantly less than that of controls (13 vs 50 mg/ml). Biliary infection is almost always present in cases with brown pigment stones. These findings suggest that bacterial infection is present at the initiation of brown pigment stone formation as well as during the period of ensuing stone growth. PMID:2295290

Akiyoshi, T; Nakayama, F



Amino Acid Composition of Crystalline Botulinum Toxin, Type a.  

National Technical Information Service (NTIS)

The amino acid composition of the crystalline material was investigated using chromatographic techniques. The results of this analysis are presented, and some of the implications they have upon the subunit structure of the toxin are discussed.

D. Stefanye E. J. Schantz L. Spero



Carnosine-related dipeptides in the mammalian brain  

Microsoft Academic Search

Carnosine and structurally related dipeptides are a group of histidine-containing molecules widely distributed in vertebrate organisms and particularly abundant in muscle and nervous tissue. Although many theories have been proposed, the biological function(s) of these compounds in the nervous system remains enigmatic.The purpose of this article is to review the distribution of carnosine-related dipeptides in the mammalian brain, with particular

L. Bonfanti; P. Peretto; S. De Marchis; A. Fasolo



Antimonic acid and sulfonated polystyrene proton-conducting polymeric composites  

Microsoft Academic Search

Polymer composites formed of a proton conductor and polyvinylidene fluoride (PVDF) are prepared. Sulfonated polystyrene (SPS) and antimonic acid (AAc) are used as organic and inorganic proton conductor, respectively. PVDF is the insulating matrix used as a binder to improve the mechanical stability of the composites compared with the pure proton conductors. The effect of the SPS and\\/or AAc on

J. M Amarilla; R. M Rojas; J. M Rojo; M. J Cubillo; A Linares; J. L Acosta



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

NASA Astrophysics Data System (ADS)

We analyzed the amino acid composition of a fragment of the Sutter's Mill meteorite (SM2) using liquid chromatography time of flight mass spectrometry. In contrast to other CM meteorites, only trace levels of amino acids were detected in SM2.

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



Fatty acid composition of serum lecithin in healthy children  

Microsoft Academic Search

Serum concentrations of cholesterol, triglycerides, phospholipids and the fatty acid composition of lecithin were determined in 107 children aged 1–15 years. The major aim of the study was to find out the normal ranges of the proportions of the essential fatty acids in lecithin for further studies of nutritional and metabolic disorders. The population contained partly children admitted for general

C. Alling; B. Westerberg




Technology Transfer Automated Retrieval System (TEKTRAN)

Sugar beet pulp and poly(lactic acid) composites were prepared by compression-heating. The resultant thermoplastics had a lower density, but they had similar or better tensile strength than pure poly(lactic acid) specimens as well as the same geometric properties. Tensile properties also depended ...


Carbon-deuterium vibrational probes of peptide conformation: Alanine dipeptide and glycine dipeptide  

NASA Astrophysics Data System (ADS)

The utility of ?-carbon deuterium-labeled bonds (C?-D) as infrared reporters of local peptide conformation was investigated for two model dipeptide compounds: C?-D labeled alanine dipeptide (Adp-d1) and C?-D2 labeled glycine dipeptide (Gdp-d2). These model compounds adopt structures that are analogous to the motifs found in larger peptides and proteins. For both Adp-d1 and Gdp-d2, we systematically mapped the entire conformational landscape in the gas phase by optimizing the geometry of the molecule with the values of ? and ?, the two dihedral angles that are typically used to characterize the backbone structure of peptides and proteins, held fixed on a uniform grid with 7.5° spacing. Since the conformations were not generally stationary states in the gas phase, we then calculated anharmonic C?-D and C?-D2 stretch transition frequencies for each structure. For Adp-d1 the C?-D stretch frequency exhibited a maximum variability of 39.4 cm-1 between the six stable structures identified in the gas phase. The C?-D2 frequencies of Gdp-d2 show an even more substantial difference between its three stable conformations: there is a 40.7 cm-1 maximum difference in the symmetric C?-D2 stretch frequencies and an 81.3 cm-1 maximum difference in the asymmetric C?-D2 stretch frequencies. Moreover, the splitting between the symmetric and asymmetric C?-D2 stretch frequencies of Gdp-d2 is remarkably sensitive to its conformation.

Miller, C. S.; Ploetz, E. A.; Cremeens, M. E.; Corcelli, S. A.



Effect of sulfuric acid in wood plastic composite  

NASA Astrophysics Data System (ADS)

Wood plastic composite was prepared with simul and MMA in the presence of methanol used as swelling agent at different proportions. Sulfuric acid was incorporated into the impregnating solution to investigate its effect on the polymer loading and tensile strength of the composite. 1% Acid solution induces the highest polymer loading. Effect of additives like NVP, TPGDA and TMPTA was also investigated. Corrosion or leaching effect of the acid on the wood samples was studied. Uptake of the impregnating solution by the samples over a period of time was determined.

Husain, M. M.; Khan, Mubarak A.; Ali, K. M. Idriss; Mustafa, A. I.



Chiral Analysis of Amino Acids Using Electrochemical Composite Bienzyme Biosensors  

Microsoft Academic Search

The construction and performance of bienzyme amperometric composite biosensors for the selective determination of l- or d-amino acids is reported. d- or l-Amino acid oxidase, horseradish peroxidase, and the mediator ferrocene were coimmobilized by simple physical inclusion into the bulk of a graphite–70% Teflon electrode matrix. Working conditions including amino acid oxidase loading and pH were optimized. Studies on the

R. Dom??nguez; B. Serra; A. J. Reviejo; J. M. Pingarrón



Effects of conservation method on fatty acid composition of silage  

Microsoft Academic Search

This experiment was conducted to investigate effects of wilting and additives on the fatty acid (FA) composition of grass silage. The crop used was timothy (Phelum pratense L., cv. Grindstad), and the additives were Proens™ (formic acid and propionic acid, 60–66g\\/100g and 25–30g\\/100g, respectively), the bacterial inoculant Siloferm® Plus (Pediococcus acidilactici and Lactobacillus plantarum) and water (control). The wilted material

K. Arvidsson; A.-M. Gustavsson; K. Martinsson



Compositions and method for controlling precipitation when acidizing sour wells  

SciTech Connect

This patent describes an acidizing composition for treating a sour well. It comprises: a base acid solution having an initial ph below 1.9; an iron sequestering agent to combine with iron present in the solution comprising at least one compound selected from the group consisting of aminopolycarboxylic acids, hydroxycarboxylic acids, cyclic polyethers and derivatives of the acids and ethers present in an amount of from about 0.25 to about 5 percent by weight of the acid solution; and a sulfide modifier to combine with sulfides present in the solution comprising at least one member selected from the group consisting of an aldehyde, acetal, hemiacetal and any other compound capable of forming an aldehyde in solution, present in an amount of from about 1 to about 4 percent by weight of the acid solution, whereby precipitation of ferric hydroxide, ferrous sulfide and elemental sulfur is inhibited as acid spending occurs.

Dill, W.R.; Walker, M.L.



Is the fatty acid composition of Daphnia galeata determined by the fatty acid composition of the ingested diet?  

Microsoft Academic Search

1. The fatty acid (FA) composition of Daphnia galeata and their algal food was analysed and showed many similarities, however, some significant differences were also found in the relative abundance of the FA C16:4 omega 3 and docosahexaenoic acid (DHA). Their relative abundances were much lower in daphnids than in their algal diet. 2. When daphnids were fed three distinct

Weers M. M. P; K. Siewertsen; R. D. Gulati



Fatty acid composition of French butters, with special emphasis on conjugated linoleic acid (CLA) isomers  

Microsoft Academic Search

Conjugated linoleic acids (CLA) are fatty acids primarily found in dairy products. These fatty acids may have potential biological properties interesting for human health. Update of French food composition data banks was needed to determine CLA levels in French dairy products and to evaluate CLA intake by the French population. As part of this investigation, we analyzed 54 butters from

Martial Ledoux; Jean-Michel Chardigny; Mariannick Darbois; Yvette Soustre; Jean-Louis Sébédio; Laurent Laloux



CE-PLoc: an ensemble classifier for predicting protein subcellular locations by fusing different modes of pseudo amino acid composition.  


Precise information about protein locations in a cell facilitates in the understanding of the function of a protein and its interaction in the cellular environment. This information further helps in the study of the specific metabolic pathways and other biological processes. We propose an ensemble approach called "CE-PLoc" for predicting subcellular locations based on fusion of individual classifiers. The proposed approach utilizes features obtained from both dipeptide composition (DC) and amphiphilic pseudo amino acid composition (PseAAC) based feature extraction strategies. Different feature spaces are obtained by varying the dimensionality using PseAAC for a selected base learner. The performance of the individual learning mechanisms such as support vector machine, nearest neighbor, probabilistic neural network, covariant discriminant, which are trained using PseAAC based features is first analyzed. Classifiers are developed using same learning mechanism but trained on PseAAC based feature spaces of varying dimensions. These classifiers are combined through voting strategy and an improvement in prediction performance is achieved. Prediction performance is further enhanced by developing CE-PLoc through the combination of different learning mechanisms trained on both DC based feature space and PseAAC based feature spaces of varying dimensions. The predictive performance of proposed CE-PLoc is evaluated for two benchmark datasets of protein subcellular locations using accuracy, MCC, and Q-statistics. Using the jackknife test, prediction accuracies of 81.47 and 83.99% are obtained for 12 and 14 subcellular locations datasets, respectively. In case of independent dataset test, prediction accuracies are 87.04 and 87.33% for 12 and 14 class datasets, respectively. PMID:21864791

Khan, Asifullah; Majid, Abdul; Hayat, Maqsood



Apple juice composition: sugar, nonvolatile acid, and phenolic profiles.  


Apples from Michigan, Washington, Argentina, Mexico, and New Zealand were processed into juice; the 8 samples included Golden Delicious, Jonathan, Granny Smith, and McIntosh varieties. Liquid chromatography was used for quantitation of sugars (glucose, fructose, sucrose, and sorbitol), nonvolatile acids (malic, quinic, citric, shikimic, and fumaric), and phenolics (chlorogenic acid and hydroxymethylfurfural [HMF]). Other determinations included pH, 0Brix, and L-malic acid. A number of compositional indices for these authentic juices, e.g., chlorogenic acid content, total malic - L-malic difference, and the HMF:chlorogenic ratio, were at variance with recommended standards. The phenolic profile was shown to be particularly influenced by gelatin fining, with peak areas decreasing by as much as 50%. The L-malic:total malic ratio serves as a better index for presence of synthetic malic acid than does the difference between the 2 determinations. No apparent differences in chemical composition could be attributed to geographic origin. PMID:3417603

Lee, H S; Wrolstad, R E


Deoxyribonucleic acid base composition of Micrococcus roseus  

Microsoft Academic Search

The percentage guanine + cytosine (GC) in the DNA of 13 strains ofMicrococcus roseus has been determined. Two methods were used to analyse the base composition, namely determination of Tm value and determination of the ratio E260\\/E280 at pH 3. The percentage GC in the strains ofM. roseus ranged from 66.2 to 73.8 and was in agreement with their present

J. Bohá?ek; M. Kocur; T. Martinec



Analysis of Fatty Acid content and composition in microalgae.  


A method to determine the content and composition of total fatty acids present in microalgae is described. Fatty acids are a major constituent of microalgal biomass. These fatty acids can be present in different acyl-lipid classes. Especially the fatty acids present in triacylglycerol (TAG) are of commercial interest, because they can be used for production of transportation fuels, bulk chemicals, nutraceuticals (?-3 fatty acids), and food commodities. To develop commercial applications, reliable analytical methods for quantification of fatty acid content and composition are needed. Microalgae are single cells surrounded by a rigid cell wall. A fatty acid analysis method should provide sufficient cell disruption to liberate all acyl lipids and the extraction procedure used should be able to extract all acyl lipid classes. With the method presented here all fatty acids present in microalgae can be accurately and reproducibly identified and quantified using small amounts of sample (5 mg) independent of their chain length, degree of unsaturation, or the lipid class they are part of. This method does not provide information about the relative abundance of different lipid classes, but can be extended to separate lipid classes from each other. The method is based on a sequence of mechanical cell disruption, solvent based lipid extraction, transesterification of fatty acids to fatty acid methyl esters (FAMEs), and quantification and identification of FAMEs using gas chromatography (GC-FID). A TAG internal standard (tripentadecanoin) is added prior to the analytical procedure to correct for losses during extraction and incomplete transesterification. PMID:24121679

Breuer, Guido; Evers, Wendy A C; de Vree, Jeroen H; Kleinegris, Dorinde M M; Martens, Dirk E; Wijffels, René H; Lamers, Packo P



Manipulating Membrane Fatty Acid Compositions of Whole Plants with Tween-Fatty Acid Esters 1  

PubMed Central

This paper describes a method for manipulating plant membrane fatty acid compositions without altering growth temperature or other conditions. Tween-fatty acid esters carrying specific fatty acids were synthesized and applied to various organs of plants growing axenically in glass jars. Treated plants incorporated large amounts of exogenous fatty acids into all acylated membrane lipids detected. Fatty acids were taken up by both roots and leaves. Fatty acids applied to roots were found in leaves, while fatty acids applied to leaves appeared in both leaves higher on the plant and in roots, indicating translocation (probably in the phloem). Foliar application was most effective; up to 20% of membrane fatty acids of leaves above the treated leaf and up to 40% of root membrane fatty acids were exogenously derived. Plants which took up exogenous fatty acids changed their patterns of fatty acid synthesis such that ratios of saturated to unsaturated fatty acids remained essentially unaltered. Fatty acid uptake was most extensively studied in soybean (Glycine max [L.] Merr.), but was also observed in other species, including maize (Zea mays L.), mung beans (Vigna radiata L.), peas (Pisum sativum L.), petunia (Petunia hybrida L.) and tomato (Lycopersicon esculentum Mill.). Potential applications of this system include studying internal transport of fatty acids, regulation of fatty acid and membrane synthesis, and influences of membrane fatty acid composition on plant physiology. Images Figure 2

Terzaghi, William B.



Amino acid composition of organic matter associated with carbonate and non-carbonate sediments  

Microsoft Academic Search

Amino acids comprise from 15 to 36% by weight of humic substances from carbonate and non-carbonate sediments. Humic and fulvic acids extracted from carbonate sediments are characterized by an amino acid composition consisting primarily of the acidic amino acids, aspartic and glutamic acid. Humic substances from non-carbonate sediments have a distinctly different amino acid composition consisting primarily of glycine and

Paul W. Carter; Richard M. Mitterer



Influence of two glutamine-containing dipeptides on growth of mammalian cells  

Microsoft Academic Search

Summary  The instability of the amino acid glutamine prompted us to investigate substitute compounds appropriate for culture conditions.\\u000a The effect of two glutamine-containing dipeptides, alanylglutamine (Ala-Gln) and glycylglutamine (Gly-Gln), on the growth\\u000a behavior of a hematopoietic cell line in culture (K562) was investigated. Growth rates and [3H]thymidine incorporation rates of cells cultivated in sterile-filtrated media, containing glutamine (Gln) or Ala-Gln or

E. Roth; G. Ollenschlager; A. Simmel; K. Langer; W. Fekl; R. Jakesz



Solution-phase submonomer diversification of aza-dipeptide building blocks and their application in aza-peptide and aza-DKP synthesis.  


Aza-peptides have been used as tools for studying SARs in programs aimed at drug discovery and chemical biology. Protected aza-dipeptides were synthesized by a solution-phase submonomer approach featuring alkylation of N-terminal benzophenone semicarbazone aza-Gly-Xaa dipeptides using different alkyl halides in the presence of potassium tert-butoxide as base. Benzophenone protected aza-dipeptide tert-butyl ester 31c was selectively deprotected at the C-terminal ester or N-terminal hydrazone to afford, respectively, aza-dipeptide acid and amine building blocks 36c and 40c, which were introduced into longer aza-peptides. Alternatively, removal of the benzophenone semicarbazone protection from aza-dipeptide methyl esters 29a-c led to intramolecular cyclization to produce aza-DKPs 39a-c. In light of the importance of aza-peptides and DKPs as therapeutic agents and probes of biological processes, this diversity-oriented solution-phase approach may provide useful tools for studying peptide science. PMID:20474040

Bourguet, Carine B; Proulx, Caroline; Klocek, Sophie; Sabatino, David; Lubell, William D



Nucleic acids, compositions and uses thereof  


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.

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)



Fatty acid composition of selected macrophytes.  


The content of total lipids and the fatty acid (FA) profile were determined for eight macroalgae (Cystoseira abies-marina, Fucus spiralis, Chaetomorpha pachynema, Codium elisabethae, Porphyra sp., Osmundea pinnatifida, Pterocladiella capillacea and Sphaeroccoccus coronopifolius). Total lipids were extracted using a solvent mixture of methanol/chloroform (2/1, v/v) and further derivatised to FA methyl esters (FAME). The analyses of FAME samples were performed by gas chromatography coupled to a flame ionisation detector. The total lipid content ranged from 0.06 to 3.54?g (per 100?g). The most abundant saturated FA were palmitic (C16:0) and myristic (C14:0), while oleic (C18:1?n-9) was the dominant monounsaturated acid. All seaweeds contained linoleic FA (C18:2?n-6). The ?-linolenic (C18:3?n-3) and eicosapentaenoic (20:5?n-3) acids were present only in Porphyra sp. (3.34%?±?0.13) and C. pachynema (0.47%?±?0.12), respectively. The n-6/n-3 and h/H ratios were low, suggesting a high nutritional value of the algae studied. PMID:22591127

Patarra, R F; Leite, J; Pereira, R; Baptista, J; Neto, A I



Modified alginate composite membranes for the dehydration of acetic acid  

Microsoft Academic Search

Alginate composite membranes cross-linked with 1,6-hexanediamine (HDM) or poly(vinyl alcohol) (PVA) were prepared by casting an aqueous solution of alginate and HDM or PVA on a hydrolyzed microporous polyacrylonitrile (PAN) membrane and characterized by pervaporation separation of acetic acid\\/water mixtures. The influence of hydrolysis of PAN support layer and HDM content in dense layer on separation performance of the composite

Xin-Ping Wang



Variation in amino acid and lipid composition of latent fingerprints.  


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

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



Cod liver oil: feed oil influences on fatty acid composition  

Microsoft Academic Search

The influence of feed oils on fatty acid compositions of cod liver oils was examined to investigate how fatty acid profiles\\u000a are modified, and to provide estimates of feed oil compositions needed to give liver oils meeting production guidelines [3–11%\\u000a 18:2n?6, 7–16% 20:5n?3 (EPA) and 6–18% 22:6n?3 (DHA)]. Attention was directed to examination of cod liver oil contents of n?6

Malcolm Jobling; Odd Leknes



Characterization of active dipeptide transport by germinating barley embryos: Effects of pH and metabolic inhibitors  

Microsoft Academic Search

A sensitive new fluorescent method is outlined for the study of peptide and amino acid transport processes. Studies on dipeptide transport in germinating barley (Hordeum vulgare.) embryos have provided evidence for accumulation of substrate against a concentration gradient, saturation kinetics, a pH optimum at pH 3.8, and inhibition by a variety of metabolic inhibitors. Acetate also inhibits transport, possibly by

C. F. Higgins; J. W. Payne



Dipeptide Synthesis by an Aminopeptidase from Streptomyces septatus TH-2 and Its Application to Synthesis of Biologically Active Peptides  

Microsoft Academic Search

Dipeptide synthesis by aminopeptidase from Streptomyces septatus TH-2 (SSAP) was demonstrated using free amino acid as an acyl donor and aminoacyl methyl ester as an acyl acceptor in 98% methanol (MeOH). SSAP retained its activity after more than 100 h in 98% MeOH, and in the case of phenylalanyl-phenylalanine methyl ester synthesis, the enzyme reaction reached equilibrium when more than

Jiro Arima; Yoshiko Uesugi; Misugi Uraji; Masaki Iwabuchi; Tadashi Hatanaka



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


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

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



Electron attachment to the dipeptide alanyl-glycine  

NASA Astrophysics Data System (ADS)

Dissociative electron attachment (DEA) to the simplest hetero dipeptide (alanyl-glycine) is studied by means of a beam experiment. The results are compared with those previously obtained from the single compounds alanine and glycine from which the dipeptide is formed. In addition to the resonances and DEA products formed from the single molecules, alanyl-glycine exhibits new resonant features right at threshold (?0 eV energy) and additional fragments which arise from the cleavage of the peptide and N-C? bond. A further strong reaction leads to the loss of a neutral water molecule. These results clearly demonstrate that the dipeptide is considerably more sensitive towards low energy electrons than its components, which is of particular relevance with respect of radiation damage of biomolecular systems.

Kopyra, Janina; König-Lehmann, Constanze; Illenberger, Eugen



Effect of altered fatty acid composition on soybean oil stability  

Microsoft Academic Search

During the last 15 years, hybridization and induced mutation breeding of soybeans have been successful in producing an altered\\u000a fatty acid composition in the extracted oil. The objective of those investigations was to produce a low-linolenic acid soybena\\u000a oil. Crude oils extracted from the seeds of three such genotypes were processed in laboratory simulations of commercial procedures\\u000a to finished deodorized

T. L. Mounts; K. Warner; G. R. List; R. Kleiman; W. R. Fehr; E. G. Hammond; J. R. Wilcox



Fatty acid composition of breast milk lipids of Nigerian women  

Microsoft Academic Search

Breast milk lipids from 13 lactating women in Southern Nigeria who were moderate to severely malnourished and whose mean body mass index (BMI) was 20.2 (± 1.9) and (16.4 (± 1.2)), respectively were separated into various neutral lipid and phospholipid fractions and analyzed for their fatty acid compositions. There were no differences in the content of free fatty acids, diglycerides,

Robert H. Glew; Jackson A. Omene; Sylvia Vignetti; Mark D'Amico; Rhobert W. Evans



Oxidative stability of soybean oils with altered fatty acid compositions  

Microsoft Academic Search

The oxidative stabilities of one canola oil and six soybean oils of various fatty acid compositions were compared in terms\\u000a of peroxide values, conjugated dienoic acid values and sensory evaluations. Two of the soybean oils (Hardin and BSR 101) were\\u000a from common commercial varieties. The other four soybean oils were from experimental lines developed in a mutation breeding\\u000a program at

Hui-Rong Liu; Pamela J. White



Fatty Acid Composition of Pistachio Nuts in Turkey  

Microsoft Academic Search

In this study oil yields and fatty acid compositions in the kernels of two varieties (Uzun and Siirt) of pistachio grown in different region of Turkey were investigated. Kernel oils were obtained by Soxhlet extraction using petroleum ether. The yields were found to be 57.1-58.9% and 56.1-62.6 respectively for the Uzun and Siirt varieties, on a moisture-free basis. Fatty acid

F. Satil; N. Azcan; K. H. C. Baser



Fatty acid composition of melon seed oil lipids and phospholipids  

Microsoft Academic Search

Fatty acid compositions of crude melon seed oil from two different sources were compared. Melon seeds fromCitrullus vulgaris (syn.C. lanatus) contained phosphatidylcholine (PC), lysophosphatidylcholine (LPC) and phosphatidylserine (PS), whereas melon seeds fromCitrullus colocynthis contained only PC and LPC, but not PS. Analysis of the total lipids revealed that the major fatty acid of the oils was 18:2n-6.Citrullus vulgaris seed oil

Casimir C. Akoh; Chigozie V. Nwosu



Predict mycobacterial proteins subcellular locations by incorporating pseudo-average chemical shift into the general form of Chou's pseudo amino acid composition.  


Mycobacterium tuberculosis (MTB) is a pathogenic bacterial species in the genus Mycobacterium and the causative agent of most cases of tuberculosis (Berman et al., 2000). Knowledge of the localization of Mycobacterial protein may help unravel the normal function of this protein. Automated prediction of Mycobacterial protein subcellular localization is an important tool for genome annotation and drug discovery. In this work, a benchmark data set with 638 non-redundant mycobacterial proteins is constructed and an approach for predicting Mycobacterium subcellular localization is proposed by combining amino acid composition, dipeptide composition, reduced physicochemical property, evolutionary information, pseudo-average chemical shift. The overall prediction accuracy is 87.77% for Mycobacterial subcellular localizations and 85.03% for three membrane protein types in Integral membranes using the algorithm of increment of diversity combined with support vector machine. The performance of pseudo-average chemical shift is excellent. In order to check the performance of our method, the data set constructed by Rashid was also predicted and the accuracy of 98.12% was obtained. This indicates that our approach was better than other existing methods in literature. PMID:22459701

Fan, Guo-Liang; Li, Qian-Zhong



Eicosapentaenoic Acid Supplementation Changes Fatty Acid Composition and Corrects Endothelial Dysfunction in Hyperlipidemic Patients  

PubMed Central

We investigated the effects of purified eicosapentaenoic acid (EPA) on vascular endothelial function and free fatty acid composition in Japanese hyperlipidemic subjects. In subjects with hyperlipidemia (total cholesterol ?220?mg/dL and/or triglycerides ?150?mg/dL), lipid profile and forearm blood flow (FBF) during reactive hyperemia were determined before and 3 months after supplementation with 1800?mg/day EPA. Peak FBF during reactive hyperemia was lower in the hyperlipidemic group than the normolipidemic group. EPA supplementation did not change serum levels of total, HDL, or LDL cholesterol, apolipoproteins, remnant-like particle (RLP) cholesterol, RLP triglycerides, or malondialdehyde-modified LDL cholesterol. EPA supplementation did not change total free fatty acid levels in serum, but changed the fatty acid composition, with increased EPA and decreased linoleic acid, ?-linolenic acid, and dihomo-?-linolenic acid. EPA supplementation recovered peak FBF after 3 months. Peak FBF recovery was correlated positively with EPA and EPA/arachidonic acid levels and correlated inversely with dihomo-?-linolenic acid. EPA supplementation restores endothelium-dependent vasodilatation in hyperlipidemic patients despite having no effect on serum cholesterol and triglyceride patterns. These results suggest that EPA supplementation may improve vascular function at least partly via changes in fatty acid composition.

Yamakawa, Ken; Shimabukuro, Michio; Higa, Namio; Asahi, Tomohiro; Ohba, Kageyuki; Arasaki, Osamu; Higa, Moritake; Oshiro, Yoshito; Yoshida, Hisashi; Higa, Tohru; Saito, Taro; Ueda, Shinichiro; Masuzaki, Hiroaki; Sata, Masataka




Technology Transfer Automated Retrieval System (TEKTRAN)

Soybean (Glycine max (L.) Merr.) oil accounts for nearly half of the edible vegetable oil production worldwide. The fatty acid composition of soybean seed oil affects its nutritional value and physical and chemical characteristics. In recent years, there has been an increasing demand to produce soy...


Oleuropein on lipid and fatty acid composition of rat heart  

Microsoft Academic Search

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

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




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...


Analysis of Sucrose Fatty Acid Esters Composition by HPLC  

Microsoft Academic Search

Two procedures for quantitative analysis of sucrose fatty acid esters composition using HPLC are described. A reversed-phase column (RP-18) was used. The mobile phases consist of: a) methanol (95%) and isopropanol (5%); b) methanol and water (5%) using UV and RI detectors.

V. R. Kaufman; N. Garti



Ontogenic changes of amino acid composition in planktonic crustacean species  

Microsoft Academic Search

Changes in amino acid composition (AAC) during ontogeny of some planktonic crustacean species commonly found in fresh and brackish coastal waters were compared. For these comparisons two calanoid copepods (Eurytemora velox and Calanipeda aquae-dulcis), two cyclopoid copepods (Diacyclops bicuspidatus odessanus and Acanthocyclops robustus) and two Daphnia (Daphnia pulicaria and Daphnia magna) species were selected. A discriminant analysis was performed to

Sandra Brucet; Dani Boix; Rocìo López-Flores; Anna Badosa; Xavier D. Quintana



Effect of undecanoic acid on lipid composition of Trichophyton rubrum  

Microsoft Academic Search

Phospholipid and neutral lipid composition of undecanoic acid (UDA) resistant mutant of Trichophyton rubrum were compared with those of the UDA sensitive parent strain of this dermatophyte. When grown in glucose-peptone broth under identical conditions, contents of neutral and phospholipids in UDA resistant mutant were nearly double of those in the UDA sensitive parent strain. Glyceride, sterol, sterol ester and

S. K. Das; A. B. Banerjee




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...


Purification and amino acid composition of monomeric and polymeric collagens  

PubMed Central

The preparations and amino acid compositions of highly purified tropocollagen and insoluble polymerized collagen are described. These collagens appear to be very suitable for comparative studies in an investigation of the cross-linkages that are introduced into tropocollagen during the formation of polymerized collagen. ImagesPlate 1Plate 2Plate 3

Steven, F. S.; Jackson, D. S.



Proximate, amino acid, fatty acid and mineral composition of raw and cooked camel (Camelus dromedarius) meat  

Microsoft Academic Search

Purpose – The purpose of the paper is to study the effects of cooking on proximate composition, amino acids, fatty acids, minerals and total, heme and non-heme iron content of camel meat. Design\\/methodology\\/approach – A total of ten longissimus thoracis muscles (500 grams) were collected between the tenth and twelfth ribs of the left side. Samples were randomly collected from

I. T. Kadim; M. R. Al-Ani; R. S. Al-Maqbaly; M. H. Mansour; O. Mahgoub; E. H. Johnson



Method of preparing and using and composition for acidizing subterranean formations  

SciTech Connect

A composition and method of acidizing or fracturing a subterranean formation comprises contacting the formation with a composition comprising an acid, urea, and a selected gelling agent. The urea is present in an amount sufficient to extend the viscous stability of the gelled acid composition in comparison to the acid and gelling agent alone.

Dill, W.R.



trans fatty acids. 4. Effects on fatty acid composition of colostrum and milk  

Microsoft Academic Search

trans Isometric fatty acids of partially hydrogenated fish oil (PHFO) consist oftrans 20?1 andtrans 22?1 in addition to thetrans isomers of 18?1, which are abundant in hydrogenated vegetable oils, such as in partially hydrogenated soybean oil (PHSBO).\\u000a The effects of dietarytrans fatty acids in PHFO and PHSBO on the fatty acid composition of milk were studied at 0 (colostrum) and

Jan Pettersen; Johannes Opstvedt



Determination of Fatty Acid Composition and Total Trans Fatty Acids in Cereal-Based Turkish Foods  

Microsoft Academic Search

The fatty acid composition and trans fatty acids of 13 cereal-based foods produced by Turkish companies were analysed by capillary gas-liquid chromatography. The total fat contents of the samples ranged from 1.8 to 37.9%. Traditional Turkish white bread and bulgur had the lowest fat content (1.8% and 2.3% respectively) and wafer the highest (37.9%). The major fatty acids in the


Cyclopropenoid fatty acid content and fatty acid composition of crude cottonseed oils from successive solvent extractions  

Microsoft Academic Search

The fatty acid composition and properties of six fractions of oil successively extracted from cottonseed meats has been investigated.\\u000a The cyclopropenoid fatty acid concn increased regularly from 0.30–1.06%, a 3.5-fold increase. This suggests that the cyclopropenoid\\u000a constituents of the oil in the seed are less accessible to the solvent. The linoleic acid concn decreased from 56.3–53.1%\\u000a accounting for a slight

A. V. Bailey; W. A. Pons; E. L. Skau



Engineered polymer nanoparticles containing hydrophobic dipeptide for inhibition of amyloid-? fibrillation.  


Protein aggregation into amyloid fibrils is implicated in the pathogenesis of many neurodegenerative diseases. Engineered nanoparticles have emerged as a potential approach to alter the kinetics of protein fibrillation process. Yet, there are only a few reports describing the use of nanoparticles for inhibition of amyloid-? 40 (A?(40)) peptide aggregation, involved in Alzheimer's disease (AD). In the present study, we designed new uniform biocompatible amino-acid-based polymer nanoparticles containing hydrophobic dipeptides in the polymer side chains. The dipeptide residues were designed similarly to the hydrophobic core sequence of A?. Poly(N-acryloyl-L-phenylalanyl-L-phenylalanine methyl ester) (polyA-FF-ME) nanoparticles of 57 ± 6 nm were synthesized by dispersion polymerization of the monomer A-FF-ME in 2-methoxy ethanol, followed by precipitation of the obtained polymer in aqueous solution. Cell viability assay confirmed that no significant cytotoxic effect of the polyA-FF-ME nanoparticles on different human cell lines, e.g., PC-12 and SH-SY5Y, was observed. A significantly slow secondary structure transition from random coil to ?-sheets during A?(40) fibril formation was observed in the presence of these nanoparticles, resulting in significant inhibition of A?(40) fibrillation kinetics. However, the polyA-FF-ME analogous nanoparticles containing the L-alanyl-L-alanine (AA) dipeptide in the polymer side groups, polyA-AA-ME nanoparticles, accelerate the A?(40) fibrillation kinetics. The polyA-FF-ME nanoparticles and the polyA-AA-ME nanoparticles may therefore contribute to a mechanistic understanding of the fibrillation process, leading to the development of therapeutic strategies against amyloid-related diseases. PMID:22897679

Skaat, Hadas; Chen, Ravit; Grinberg, Igor; Margel, Shlomo



Modified dipeptide-based nanoparticles: vehicles for targeted tumor drug delivery.  


Aim: Different nanoparticles have been investigated to deliver chemotherapeutic agents, but complex synthesis procedures and biocompatibility issues raise concerns in developing them for safe human usage. The aim of this work is to develop ?,?-dehydrophenylalanine-containing, self-assembled, amphipathic dipeptide nanoparticles for tumor-targeted drug delivery and therapy. Material & methods: Solution-phase peptide synthesis was used to synthesize dipeptides. Nanoparticles were prepared by molecular self-assembly. A tumor distribution study was carried out using a radiolabeling method. Tumor regression studies were carried out in murine ascitic tumors in BALB/c mice and breast tumor xenografts in nude mice. Results: Arg-?,?-dehydrophenylalanine formed self-assembled nanoparticles that could be easily derivatized with folic acid. Folic acid-derivatized nanoparticles showed enhanced cellular uptake and, when loaded with doxorubicin, showed enhanced tumor regression compared with underivatized nanoparticles or native drug, without any adverse side effects, both in vitro and in vivo. Original submitted 20 April 2012; Revised submitted 9 November 2012. PMID:23398497

Panda, Jiban J; Kaul, Ankur; Kumar, Santosh; Alam, Shadab; Mishra, Anil K; Kundu, Gopal C; Chauhan, Virander S



Artificial rearing with docosahexaenoic acid and n-6 docosapentaenoic acid alters rat tissue fatty acid composition.  


Docosahexaenoic acid (DHA; 22:6n-3) and n-6 docosapentaenoic acid (DPAn-6; 22:5n-6) are components of enriched animal feed and oil derived from Schizochytrium species microalgae. A one generation, artificial rearing model from day 2 after birth onward (AR) and a dam-reared control group (DAM) were used to examine DPAn-6 feeding on the fatty acid composition of various rat tissues at 15 weeks of age. Four AR diets were based on an n-3 fatty acid-deficient, 18:2n-6-based artificial milk with 22:6n-3 and/or 22:5n-6 added: AR-LA, AR-DHA, AR-DPAn-6, and AR-DHA+DPAn-6. The 22:6n-3 levels for the DAM, AR-DHA, and AR-DHA+DPAn-6 groups tended to be similar and higher than in the AR-LA and AR-DPAn-6 groups. The levels of 22:5n-6 tended to be higher only in the absence of dietary 22:6n-3. Adipose levels of 22:5n-6 was the only exception, as 22:5n-6 was significantly higher in AR-DHA+DPAn-6 than was observed in either the DAM or the AR-DHA group. There were no differences in 20:4n-6 levels within the tissues examined. In conclusion, 22:5n-6 replaces 22:6n-3 in the absence of 22:6n-3 only and does not appear to compete with 22:6n-3 in the presence of dietary 22:6n-3, suggesting that oils containing 22:5n-6 and 22:6n-3 may be a good dietary source of 22:6n-3. PMID:17703057

Stark, Ken D; Lim, Sun-Young; Salem, Norman



Deoxyribonucleic Acid Base Composition of Some Members of the Micrococcaceae  

PubMed Central

Auletta, Angela E. (Catholic University, Washington, D.C.), and E. R. Kennedy. Deoxyribonucleic acid base composition of some members of the Micrococcaceae. J. Bacteriol. 92:28–34. 1966.—Thirty-seven strains from the genera Micrococcus, Staphylococcus, Gaffkya, and Sarcina were examined for deoxyribonucleic acid base composition and biochemical activity. Organisms were tested for production of catalase, coagulase, deoxyribonuclease, oxidase, phosphatase, hydrogen sulfide, indole, and acetoin; nitrate reduction; gelatin, starch, and urea hydrolysis; citrate and ammonium phosphate utilization; NaCl tolerance; growth at 10 and 45 C, and growth in litmus milk. They were tested for production of acid from dextrose and mannitol under anaerobic conditions, and for aerobic production of acid from dextrose, mannitol, lactose, sucrose, raffinose, maltose, xylose, and glycerol. Organisms could be divided into two groups on the basis of guanine-cytosine (GC) content. Group I had an average GC content of 32%, and included all organisms which produced acid from dextrose. Group II had an average GC content of 62%, and included those organisms incapable of producing acid from dextrose under anaerobic conditions. Sarcina ureae had a GC content of 43%.

Auletta, Angela E.; Kennedy, E. R.



Synthesis of acid-functionalized composite via surface deposition of acid-containing amorphous carbon  

NASA Astrophysics Data System (ADS)

A synthetic procedure, including two steps: a hydrothermal treatment using H2SO4 solution and a thermal treatment with concentrated H2SO4 in Teflon-lined stainless autoclaves was developed to synthesize acid-functionalized composite. In this process, the carbonization of glucose which contributed to the formation of carbon species with acid functional groups occurred on the silica surface. The resultant composite, investigated by powder XRD, low temperature N2 sorption and TEM, possessed well-defined mesostructure. And it was determined by XPS that amorphous carbon was deposited at the silica surface of SBA-15. The presence of multi-functional groups in the composite was confirmed by FT-IR results. Furthermore, carboxylic and sulfonic groups could be incorporated into the composite material via the covalent bond. The composite was employed as the catalyst for the acetalization of carbonyl compounds. It was suggested that acid sites were well dispersed, which was responsible for the good performance in the catalytic test. According to these facts, a synthesis route for mesostructured composite with acid functional groups has been proposed.

Du, Bin; Zhang, Xuan; Lou, Lan-Lan; Dong, Yanling; Liu, Gaixia; Liu, Shuangxi



Asymmetric synthesis of chiral organofluorine compounds: use of nonracemic fluoroiodoacetic acid as a practical electrophile and its application to the synthesis of monofluoro hydroxyethylene dipeptide isosteres within a novel series of HIV protease inhibitors.  


Two stereoselective routes to a series of diastereomeric inhibitors of HIV protease, monofluorinated analogues of the Merck HIV protease inhibitor indinavir, are described. The two routes feature stereoselective construction of the fluorinated core subunits by asymmetric alkylation reactions. The first-generation syntheses were based on the conjugate addition of the lithium enolate derived from pseudoephedrine alpha-fluoroacetamide to nitroalkene 12, a modestly diastereoselective transformation. A more practical second-generation synthetic route was developed that is based on a novel method for the asymmetric synthesis of organofluorine compounds, by enolate alkylation using optically active fluoroiodoacetic acid as the electrophile in combination with a chiral amide enolate. Resolution of fluoroiodoacetic acid with ephedrine provides either enantiomeric form of the electrophile in > or = 96% ee. Alkylation reactions with this stable and storable chiral fluorinated precursor are shown to proceed in a highly stereospecific manner. With the development of substrate-controlled syn- or anti-selective reductions of alpha-fluoro ketones 44 and 45 (diastereomeric ratios 12:1-84:1), efficient and stereoselective routes to each of the four targeted inhibitors were achieved. The optimized synthetic route to the most potent inhibitor (syn,syn-4, K(i) = 2.0 nM) proceeded in seven steps (87% average yield per step) from aminoindanol hydrocinnamide 40 and (S)-fluoroiodoacetic acid, and allowed for the preparation of more than 1 g of this compound. The inhibition of HIV-1 protease by each of the fluorinated inhibitors was evaluated in vitro, and the variation of potency as a function of inhibitor stereochemistry is discussed. PMID:11472148

Myers, A G; Barbay, J K; Zhong, B



Effects of fibric acid derivatives on biliary lipid composition.  


Fenofibrate, a potent analogue of clofibrate, causes changes in biliary lipid composition similar to those seen with clofibrate and other derivatives of fibric acid, although there is a suggestion that the increase in cholesterol content may be accompanied by an increase in phospholipid content as well as a decrease in bile acid content. This may favor liquid crystal formation, and fenofibrate may have less propensity to cause gallstones than would other derivatives. Many other factors are also important in determining whether supersaturated bile will result in gallstone formation, and the use of this compound should be monitored in the future to determine the clinical importance of these findings. PMID:3318452

Palmer, R H




Technology Transfer Automated Retrieval System (TEKTRAN)

Corn oil, a by-product of the wet-milling industry, is found mainly in the germ of corn seeds. Typical dent corn oil has the following fatty acid composition: 61.9 % linoleic acid, 24.1 % oleic acid, 11.0 % palmitic acid, 2.0 % stearic acid, 0.7 % linolenic acid, and traces of other fatty acids, wit...


Analysing the substrate multispecificity of a proton-coupled oligopeptide transporter using a dipeptide library  

PubMed Central

Peptide uptake systems that involve members of the proton-coupled oligopeptide transporter (POT) family are conserved across all organisms. POT proteins have characteristic substrate multispecificity, with which one transporter can recognize as many as 8,400 types of di/tripeptides and certain peptide-like drugs. Here we characterize the substrate multispecificity of Ptr2p, a major peptide transporter of Saccharomyces cerevisiae, using a dipeptide library. The affinities (Ki) of di/tripeptides toward Ptr2p show a wide distribution range from 48?mM to 0.020?mM. This substrate multispecificity indicates that POT family members have an important role in the preferential uptake of vital amino acids. In addition, we successfully establish high performance ligand affinity prediction models (97% accuracy) using our comprehensive dipeptide screening data in conjunction with simple property indices for describing ligand molecules. Our results provide an important clue to the development of highly absorbable peptides and their derivatives including peptide-like drugs.

Ito, Keisuke; Hikida, Aya; Kawai, Shun; Lan, Vu Thi Tuyet; Motoyama, Takayasu; Kitagawa, Sayuri; Yoshikawa, Yuko; Kato, Ryuji; Kawarasaki, Yasuaki



Analysing the substrate multispecificity of a proton-coupled oligopeptide transporter using a dipeptide library.  


Peptide uptake systems that involve members of the proton-coupled oligopeptide transporter (POT) family are conserved across all organisms. POT proteins have characteristic substrate multispecificity, with which one transporter can recognize as many as 8,400 types of di/tripeptides and certain peptide-like drugs. Here we characterize the substrate multispecificity of Ptr2p, a major peptide transporter of Saccharomyces cerevisiae, using a dipeptide library. The affinities (Ki) of di/tripeptides toward Ptr2p show a wide distribution range from 48?mM to 0.020?mM. This substrate multispecificity indicates that POT family members have an important role in the preferential uptake of vital amino acids. In addition, we successfully establish high performance ligand affinity prediction models (97% accuracy) using our comprehensive dipeptide screening data in conjunction with simple property indices for describing ligand molecules. Our results provide an important clue to the development of highly absorbable peptides and their derivatives including peptide-like drugs. PMID:24060756

Ito, Keisuke; Hikida, Aya; Kawai, Shun; Lan, Vu Thi Tuyet; Motoyama, Takayasu; Kitagawa, Sayuri; Yoshikawa, Yuko; Kato, Ryuji; Kawarasaki, Yasuaki



Mechanistic investigations into the asymmetric transfer hydrogenation of ketones catalyzed by pseudo-dipeptide ruthenium complexes.  


The combination of N-Boc-protected alpha-amino acid hydroxyamides (pseudo-dipeptides) and [{Ru(p-cymene)Cl(2)}(2)] resulted in the formation of superior catalysts for the asymmetric transfer hydrogenation (ATH) of non-activated aryl alkyl ketones in propan-2-ol. The overall kinetics of the ATH of acetophenone to form 1-phenylethanol in the presence of ruthenium pseudo-dipeptide catalysts were studied, and the individual rate constants for the processes were determined. Addition of lithium chloride to the reaction mixtures had a strong influence on the rates and selectivities of the processes. Kinetic isotope effects (KIEs) for the reduction were determined and the results clearly show that the hydride transfer is rate-determining, whereas no KIEs were detected for the proton transfer. From these observations a novel bimetallic outer-sphere-type mechanism for these ATH process is proposed, in which the bifunctional catalysts mediate the transfer of a hydride and an alkali metal ion between the hydrogen donor and the substrate. Furthermore, the use of a mixture of propan-2-ol and THF (1:1) proved to enhance the rates of the ATH reactions. A series of aryl alkyl ketones were reduced under these conditions in the presence of 0.5 mol % of catalyst, and the corresponding secondary alcohols were formed in high yields and with excellent enantioselectivities (>99% ee) in short reaction times. PMID:19388029

Wettergren, Jenny; Buitrago, Elina; Ryberg, Per; Adolfsson, Hans



Microalgal fatty acid composition: implications for biodiesel quality  

Microsoft Academic Search

The fuel properties of microalgal biodiesel are predicted using published microalgal fatty acid (FA) compositions and predictive\\u000a fuel models. Biodiesels produced from the microalgae investigated are predicted to have extremely poor oxidative stabilities\\u000a and the majority also have poor cold-flow properties. The cetane number in most cases is out of specification, but less so\\u000a than the oxidative stability and cold

Graham Robert Stansell; Vincent Myles Gray; Stuart David Sym


Conifer seeds: Oil content and fatty acid composition  

Microsoft Academic Search

The seed oils from twenty-five Conifer species (from four families—Pinaceae, Cupressaceae, Taxodiaceae, and Taxaceae) have\\u000a been analyzed, and their fatty acid compositions were established by capillary gas-liquid chromatography on two columns with\\u000a different polarities. The oil content of the seeds varied from less than 1% up to 50%. Conifer seed oils were characterized\\u000a by the presence of several ?5-unsaturated polymethylene-interrupted

Robert L. Wolff; Laurent G. Deluc; Anne M. Marpeau



Fatty Acid Composition of Rat Liver Lipids during Choline Deficiency  

Microsoft Academic Search

The fatty acid compositions of whole liver triglycérides,diglycerides, total phospholipids, and lecithin, and mitochondrial total phospholipids and lecithin were determined on rats which had developed fatty livers after they had been fed a low protein, choline-deficient diet for 10 or 28 days. Experiments were conducted with either a hydrogenated vegetable oil or safflower oil as the source of dietary fat.




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

Microsoft Academic Search

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

Yeng-Fong Shih; Chien-Chung Huang


Genetic Regulation of Unsaturated Fatty Acid Composition in C. elegans  

Microsoft Academic Search

Delta-9 desaturases, also known as stearoyl-CoA desaturases, are lipogenic enzymes responsible for the generation of vital components of membranes and energy storage molecules. We have identified a novel nuclear hormone receptor, NHR-80, that regulates delta-9 desaturase gene expression in Caenorhabditis elegans. Here we describe fatty acid compositions, lifespans, and gene expression studies of strains carrying mutations in nhr-80 and in

Trisha J Brock; John Browse; Jennifer L Watts



Flax Fibers as Reinforcement in Poly (Lactic Acid) Biodegradable Composites  

Microsoft Academic Search

\\u000a In our research, poly (lactic acid) (PLA) film was used in combination with flax fibers as reinforcement to generate biodegradable\\u000a composites by a film stacking technique and hot-press. The research of the relationship between the main process parameters\\u000a and the performance of the board are done by the orthogonal experiments, then the various factors to influence the performance\\u000a were analyzed

Yuan Yuan; Minghui Guo; Yong Wang




PubMed Central

Falkow, Stanley (Walter Reed Army Institute of Research, Washington D.C.), I. R. Ryman, and O. Washington. Deoxyribonucleic acid base composition of Proteus and Providence organisms. J. Bacteriol. 83:1318–1321. 1962.—Deoxyribonucleic acids (DNA) from various species of Proteus and of Providence bacteria have been examined for their guanine + cytosine (GC) content. P. vulgaris, P. mirabilis, and P. rettgeri possess essentially identical mean GC contents of 39%, and Providence DNA has a GC content of 41.5%. In marked contrast, P. morganii DNA was found to contain 50% GC. The base composition of P. morganii is only slightly lower than those observed for representatives of the Escherichia, Shigella, and Salmonella groups. Aerobacter and Serratia differ significantly from the other members of the family by their relatively high GC content. Since a minimal requirement for genetic compatibility among different species appears to be similarity of their DNA base composition, it is suggested that P. morganii is distinct genetically from the other species of Proteus as well as Providence strains. The determination of the DNA base composition of microorganisms is important for its predictive information. This information should prove of considerable value in investigating genetic and taxonomic relationships among bacteria.

Falkow, Stanley; Ryman, I. R.; Washington, O.



Amino Acid Composition-Dependent Elasticity of SPIDER Silk  

NASA Astrophysics Data System (ADS)

Spider silk exhibits excellent mechanical features in both toughness and extensibility. In recent years considerable investigations have focused on it. The understanding of spider silk protein is important for the development bionic silk. In this paper, we study by Monte Carlo simulation the force-of-extension property of spider silk proteins as a function of the residue composition for major and minor ampullate glands of typical Araneid orb weaver as well as that for one artificial spider silk. The results are also compared with those from a designed protein whose amino acid composition is uniform. The results clearly show that the major and minor ampullate gland proteins are much tougher than the designed protein, whereas the artificial protein, as a model of a nature spider silk, does have good mechanical properties. Our simulation reveals that mechanical property of a spider silk protein is dependent on its amino acid composition and that an excellent result of natural evolution is manifest in the composition of the spider silk protein.

Zhang, Yong; Dai, Luru; Ou-Yang, Zhong-Can


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


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

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



Evaluation of table grape genetic resources for sugar, organic acid, and amino acid composition of berries  

Microsoft Academic Search

Variations in the sugar, organic acid, and amino acid composition of table grape berries were determined in three successive\\u000a years in 129 grape cultivars. Three regional groups were represented among these cultivars; European, North American, and\\u000a Japanese. All cultivars are conserved at the Fukuoka Agricultural Research Center in Japan. Three representative ripe average-sized\\u000a bunches were selected from one vine per

Mikio Shiraishi; Hiroyuki Fujishima; Hiroyuki Chijiwa



The effect of conjugated linoleic acid on plasma lipoproteins and tissue fatty acid composition in humans  

Microsoft Academic Search

Conjugated linoleic acid (CLA) has been suggested by some animal studies to possess antiatherogenic properties. To determine,\\u000a in humans, the effect of dietary CLA on blood lipids, lipoproteins, and tissue fatty acid composition, we conducted a 93-d\\u000a study with 17 healthy female volunteers at the Metabolic Research Unit of the Western Human Nutrition Research Center. Throughout\\u000a the study, subjects were

P. Benito; G. J. Nelson; D. S. Kelley; G. Bartolini; P. C. Schmidt; V. Simon



Effects of neurotensin dipeptide analog dilept on dopamine metabolism and synthesis in the nucleus accumbens of Wistar rats.  


We studied the effects of neurotensin dipeptide analog Dilept (N-caproyl-L-prolyl-L-tyrosine methyl ester) on dopamine metabolism and synthesis in the nucleus accumbens of Wistar rats. Dilept increased the levels of dopamine and its metabolites (homovanillic acid and dioxyphenylalanine) and stimulated dopamine turnover in this structure. Dilept accelerated dopamine synthesis under conditions of pulsed activity blockade in dopaminergic neuron by injection of ?-butyrolactone combined with inhibition of aromatic acid decarboxylase with 3-hydroxybenzylhydrazine. The spectrum of pharmacological activities of Dilept towards the dopaminergic system of the nucleus accumbens was similar to that of atypical neuroleptics and neurotensin (endogenous antipsychotic). PMID:23113260

Shubenina, E V; Kudrin, V S; Klodt, P M; Narkevich, V B; Kuznetsova, E A; Gudasheva, T A; Ostrovskaya, R U



Compositional and source characterization of base progressively extracted humic acids using pyrolytic gas chromatography mass spectrometry  

Microsoft Academic Search

Cyclic base extraction is a commonly used method for the isolation of humic acids from soils and sediments. However, every extract may differ in chemical composition due to the complex nature of humic acids. To better understand the chemical composition of each extract, the heterogeneous property of humic acids and their speciation in environmental samples, eight fractions of humic acids

Li Li; Wanglu Jia; Ping’an Peng; Guoying Sheng; Jiamo Fu; Weilin Huang



Taxonomy of the Neisseriae: Deoxyribonucleic Acid Base Composition, Interspecific Transformation, and Deoxyribonucleic Acid Hybridization  

Microsoft Academic Search

Deoxyribonucleic acid (DNA) base composition, intergenic transformation efficiency, and DNA hybridization were used to determine the relatedness of a variety of established or proposed species of Neisseria and Branhamella. These studies indicated that these bacteria form three genetic groupings. Group I, comprised of N. meningitidis, N. gonorrhoeae, N. subflava, N. flava, N. perflava, N. sicca, N. mucosa, N. cinerea, N.




U373-MG cells express PepT2 and accumulate the fluorescently tagged dipeptide-derivative ?-Ala-Lys-N(?)-AMCA.  


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. We were able to demonstrate that U373-MG cells express PepT2-mRNA and translocate ?-Ala-Lys-N(?)-AMCA via PepT2 into the cytoplasm. Previous results demonstrated that ?-Ala-Lys-N(?)-AMCA specifically accumulates in differentiated and dedifferentiated astrocytes but neither in differentiated nor dedifferentiated oligodendrocytes and in neurons. U373-MG cells were incubated with estradiol, testosterone, thyronine, dexamethasone, dibutyryl cyclic adenosine monophosphate and tetradecanoylphorbol acetate in order to detect potential substance-dependent changes in dipeptide uptake. There was no significant increase or decrease of ?-Ala-Lys-N(?)-AMCA-uptake after stimulation. Northern blot analyses confirmed that PepT2-mRNA is expressed in U373-MG and glial cells but showed no regulation of PepT2-mRNA expression in both cell types. Future investigations might offer the opportunity of an anti-tumor therapy with cytotoxic agents linked to a dipeptide-derivative such as ?-Ala-Lys. PMID:20868728

Zimmermann, Mathias; Kappert, Kai; Stan, Alexandru Constantin



Fragmentation of protonated dipeptides containing arginine. Effect of activation method  

Microsoft Academic Search

The fragmentation reactions of the protonated dipeptides Gly-Arg and Arg-Gly have been studied using collision-induced dissociation\\u000a (CID) in a quadrupole ion trap, by in-source CID in a single-quadrupole mass spectrometer and by CID in the quadrupole cell\\u000a of a QqTOF mass spectrometer. In agreement with earlier quadrupole ion trap studies (Farrugia, J. M.; O’Hair, R. A. J., Int. J. Mass

Matthew W. Forbes; Rebecca A. Jockusch; Alex B. Young; Alex G. Harrison



Energetics of Cyclic Dipeptide Crystal Packing and Solvation  

PubMed Central

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.

Brady, G. Patrick; Sharp, Kim A.



An amino acid composition criterion for membrane active antimicrobials  

NASA Astrophysics Data System (ADS)

Membrane active antimicrobials (AMPs) are short amphipathic peptides with broad spectrum anti microbial activity. While it is believed that their hydrophobic and cationic moieties are responsible for membrane-based mechanisms of action, membrane disruption by AMPs is manifested in a diversity of outcomes, such as pore formation, blebbing, and budding. This complication, along with others, have made a detailed, molecular understanding of AMPs difficult. We use synchrotron small angle xray scattering to investigate the interaction of model bacterial and eukaryotic cell membranes with archetypes from beta-sheet AMPs (e.g. defensins) and alpha-helical AMPs (e.g. magainins). The relationship between membrane composition and peptide induced changes in membrane curvature and topology is examined. By comparing the membrane rearrangement and phase behavior induced by these different peptides we will discuss the importance of amino acid composition on AMP design.

Schmidt, Nathan; Hwee Lai, Ghee; Mishra, Abhijit; Bong, Dennis; McCray, Paul, Jr.; Selsted, Michael; Ouellette, Andre; Wong, Gerard



Quantitative effects of dietary polyunsaturated fats on the composition of fatty acids in rat tissues  

Microsoft Academic Search

A method combining data on fatty acid composition into subsets is used to illustrate general relative competitive selectivities\\u000a in the metabolic and transport events that maintain fatty acid compositions in tissue lipids and to minimize differences among\\u000a tissues or species in the amount of individual fatty acids. Fatty acid compositions of triglycerides and phospholipids in\\u000a several tissues of the rat

William E. M. Lands; Anna Morris; Bozena Libelt



Acid gas scrubbing by composite solvent-swollen membranes  


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 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.

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



Acid gas scrubbing by composite solvent-swollen membranes  


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.

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



Growth medium affects the cellular fatty acid composition of Pasteurellaceae.  


We studied the cellular fatty acid composition of 10 Actinobacillus (A.) and Pasteurella (P.) reference strains grown on 2 types of agar by the MIDI Microbial Identification System (MIS). A. capsulatus, A. equuli, A. lignieresii, A. ureae, A. dagmatis, P. gallinarum, P. haemolytica, P. multocida, P. pneumotropica biotypes Heyl and Jawetz were grown on GC agar supplemented with ascitic fluid and X and V factor (Levinthal's agar = LA agar) or GC agar supplemented with vitox and hemoglobin (VH agar) on 3 to 7 and 7 to 16 occasions respectively and fatty acid methylester (FAME) profiles were submitted to principal component analysis (PCA). All Pasteurellaceae strains showed FAME profiles typical for the family. Maximum coefficients of variation of the percentage of the 3 major FAMEs 14:0, 16:0, and 16:1 cis were 0.03, 0.03 and 0.03 for Pasteurellaceae strains grown on VH agar and 0.09, 0.17 and 0.09 respectively for strains grown on LA agar. PCA of FAME profiles obtained with growth from LA agar generally did not allow species separation of the Pasteurellaceae but most species were clearly discriminated by PCA when they were grown on VH agar. Our findings indicate that the growth medium had a significant effect on the reproducibility of fatty acid profiling in Pasteurellaceae and that PCA of fatty acid data obtained under standardized growth conditions may discriminate Pasteurellaceae species. PMID:10096162

Boot, R; Thuis, H C; Reubsaet, F A



IR-LD spectroscopic characterization of L-Tryptophan containing dipeptides.  


IR-spectroscopic and stereo-structural analysis of aromatic l-Tryptophan containing dipeptides l-Tryptophan-l-Tryptophan (Trp-Trp), l-Tyrosine-l-Tryptophan (Tyr-Trp) and cyclo(Trp-Trp) have been carried out by means of solid-state linear-dichroic infrared (IR-LD) spectroscopy of oriented as suspension in nematic liquid crystal solids. The experimental data have been compared with analogous ones of the simple amino acids l-Tyrosnine (l-Tyr) and l-Tryptophan (l-Trp). In cyclo(Trp-Trp), the IR-spectral changes towards the IR-ones of acyclic Trp-Trp have been determined. A theoretical analysis of Tyr-Trp at Hartree-Fock level of theory and 6-31G** basis set is also applied. PMID:16488186

Ivanova, Bojidarka B



Effects of gamma-linolenic acid and docosahexaenoic acid in formulae on brain fatty acid composition in artificially reared rats.  


This study evaluated the effects of dietary supplementation with gamma-linolenic acid (GLA, 18:3n-6) and docosahexaenoic acid (DHA, 22:6n-3) on the fatty acid composition of the neonatal brain in gastrostomized rat pups reared artificially from days 5-18. These pups were fed rat milk substitutes containing fats that provided 10% linoleic acid and 1% alpha-linolenic acid (% fatty acids) and, using a 2x3 factorial design, one of two levels of DHA (0.5 and 2.5%), and one of three levels of GLA (0.5, 1.0, and 3.0%). A seventh artificially reared group served as a reference group and was fed 0.5% DHA and 0.5% arachidonic acid (AA, 20:4n-6); these levels are within the range of those found in rat milk. The eighth group, the suckled control group, was reared by nursing dams fed a standard American Institute of Nutrition 93M chow. The fatty acid composition of the phosphatidylethanolamine, phosphatidylcholine, and phosphatidylserine/phosphatidylinositol membrane fractions of the forebrain on day 18 reflected the dietary composition in that high levels of dietary DHA resulted in increases in DHA but decreases in 22:4n-6 and 22:5n-6 in brain. High levels of GLA increased 22:4n-6 but, in contrast to previous findings with high levels of AA, did not decrease levels of DHA. These results suggest that dietary GLA, during development, differs from high dietary levels of AA in that it does not lead to reductions in brain DHA. PMID:10580333

Ward, G R; Huang, Y S; Xing, H C; Bobik, E; Wauben, I; Auestad, N; Montalto, M; Wainwright, P E



Physical and sensory properties of dairy products from cows with various milk fatty acid compositions.  


Dairy products from milk of cows fed diets rich in polyunsaturated fatty acids have a more health-promoting fatty acid composition and are softer but often have oxidized flavors. Dairy products made from cow's milk that has more- or less-unsaturated fatty acid compositions were tested for differences in texture and flavor from those made from bulk-tank milk. The milk was manufactured into butter, vanilla ice cream, yogurt, Provolone cheese, and Cheddar cheese. The products were analyzed for fatty acid composition, physical properties, and flavor. Milk of cows with a more monounsaturated fatty acid composition yielded products with a more monounsaturated fatty acid composition that were softer and had a satisfactory flavor. Thus, selection of cows for milk fatty acid composition can be used to produce dairy products that are probably more healthful and have a softer texture. PMID:15161209

Chen, She; Bobe, Gerd; Zimmerman, Shelly; Hammond, Earl G; Luhman, Cindie M; Boylston, Terri D; Freeman, Albert E; Beitz, Donald C



Diet-induced changes in lipid and fatty acid composition of Artemia salina  

Microsoft Academic Search

The influence of diet on lipid and fatty acid composition of the brine shrimp Artemia salina nauplii was investigated. Various diets with different lipid composition and fatty acid profiles were fed to nauplii for 2 weeks. The lipid composition of microalgal diets, Isochrysis galbana, Phaeodactylum tricornutum and Nannochloropsis oculata and baker’s yeast was analyzed. Newly hatched nauplii were examined before

Natalia V Zhukova; Andrey B Imbs; Lia Fa Yi



Adansonian Analysis and Deoxyribonucleic Acid Base Composition of Serratia marcescens  

PubMed Central

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.

Colwell, R. R.; Mandel, M.



Colorectal cancer cell growth inhibition by linoleic acid is related to fatty acid composition changes  

PubMed Central

Polyunsaturated fatty acids (PUFAs) possess anti-cancer action both in vitro and in vivo. In the present study, we detected cell viability with methyl thiazolyl tetrazolium (MTT) assay and cell membrane permeability with propidium iodide (PI) fluorescence dyeing, and calculated cell membrane fluidity change as fluorescence anisotropy. Fatty acid content in cells was measured by gas chromatography/mass spectroscopy (GC/MS), and the relationship between fatty acid composition and cell viability was studied. We observed that n-6 PUFA linoleic acid (LA) inhibited tumor cell growth at high concentrations (?300 µmol/L), while low concentrations (100–200 µmol/L) seemed to promote cell proliferation. Analyses of cell membrane permeability, cell membrane fluidity, and cell fatty acid composition suggested that the anti-cancer action of LA could be related to changes in the ratio of n-6 to n-3 PUFAs. We observed that pre-incubation of cancer cells with 100 µmol/L LA for 24 h enhanced cell sensitivity to the cytotoxic action of LA, whereas undifferentiated cell line LoVo seemed to have a distinct path in LA-induced death. These results showed that one of the mechanisms by which supplementation of LA induces cancer cell death could be altering the ratio of n-6/n-3 PUFAs, and this may be related to cell differentiation status.

Lu, Xiao-feng; He, Guo-qing; Yu, Hai-ning; Ma, Qi; Shen, Sheng-rong; Das, Undurti N.




Microsoft Academic Search

Summary. In the present study we have examined the influence of single spraying with simulated acid rain (pH 1.8) on the content of main lipid classes and their fatty acid composition in the thylakoid membranes of bean plants. Acid stress caused considerable changes in the investigated parameters. A decline in the content of linolenic acid, a highly unsatureted fatty acid

Violeta Velikova; Albena Ivanov; Ivan Yordanov


Effect of provenance on free amino acid and chemical composition of Scots pine needles  

Microsoft Academic Search

Free amino acid (16 amino acids) and chemical composition (N, P, K, Mg, Ca, S, Fe, Mn, Cu, Zn) of Scots pine (Pinus sylvestris L.) needles were compared between six provenances in three different experimental areas. The main free amino acids in the\\u000a needles were in the sequence of quantity; glutamic acid, glutamine, arginine and ?-aminobutyric acid. There were no

Hannu Raitio; Tytti Sarjala



Amino acid composition of spring wheats and losses of lysine during chapati baking  

Microsoft Academic Search

Forty-four spring wheat varieties representing 64 years of wheat cultivar releases were evaluated for amino acid composition. The concentration of several amino acids differed among the wheat varieties but amino acids did not significantly consistently among wheat varieties and growth conditions. Significant differences existed in amino acid score due to wheat varieties and crop years. The variations in amino acids

Faqir M. Anjum; Ijaz Ahmad; Masood S. Butt; M. A. Sheikh; Imran Pasha



Evaluation of Fatty Acid and Amino Acid Compositions in Okra (Abelmoschus esculentus) Grown in Different Geographical Locations  

PubMed Central

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.

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



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


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

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



The major metabolite of dipeptide piracetam analogue GVS-111 in rat brain and its similarity to endogenous neuropeptide cyclo- l -prolylglycine  

Microsoft Academic Search

Summary  The metabolism of a new piracetam analogue, the dipeptide cognitive enhancer N-phenylacetyl-l-prolylglycine ethyl ester (GVS-111) was studied in vivo. GVS-111 itself was not found in rat brain 1 h after 5 mg\\/kg i.p.\\u000a administration up to limit of detection (LOD) under high performance liquid chromatography (HPLC) conditions. Three substances\\u000a corresponding to the three possible GVS-111 metabolites, namely phenylacetic acid, prolylglycine

T. A. Gudasheva; S. S. Boyko; R. U. Ostrovskaya; T. A. Voronina; V. K. Akparov; S. S. Trofimov; G. G. Rozantsev; A. P. Skoldinov; V. P. Zherdev; S. B. Seredenin



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

NASA Astrophysics Data System (ADS)

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.

Atik, A. Emin; Yalcin, Talat



Protonated dipeptide losses from b(5) and b(4) ions of side chain hydroxyl group containing pentapeptides.  


In this study, C-terminal protonated dipeptide eliminations were reported for both b5 and b4 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 b5 and b4 ion (except b4 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 b5 and b4 ions. In addition, the ions at m/z 295 and 281 were detected as common fragments in all b5 and b4 ion (except b4 ion of AYVYI) mass spectra, respectively, for AXVYI model peptide series. The MS(4) 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 b5 and b4 ions can be useful in assigning the correct and reliable peptide sequences for high-throughput proteomic studies. PMID:23900715

Atik, A Emin; Yalcin, Talat



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

PubMed Central

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.

Estivariz, Concepcion 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.



Fatty acid and sn-2 fatty acid composition in human milk from Granada (Spain) and in infant formulas  

Microsoft Academic Search

Objective: To investigate differences in fatty acid and sn-2 fatty acid composition in colostrum, transitional and mature human milk, and in term infant formulas.Setting: Departament de Nutrició i Bromatologia, University of Barcelona, Spain and University Hospital of Granada, Spain.Subjects: One-hundred and twenty mothers and 11 available types of infant formulas for term infants.Design: We analysed the fatty acid composition of

A López-López; MC López-Sabater; C Campoy-Folgoso; M Rivero-Urgell; AI Castellote-Bargalló



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

Microsoft Academic Search

Aqua cultured fish (sea bream) were irradiated by Cobalt-60 at commercial irradiation facility at dose of 2.5 and 5kGy 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%

Nuray Erkan; Özkan Özden



Mechanism of a model dipeptide transport across blood-ocular barriers following systemic administration  

Microsoft Academic Search

The purposes of this study were to provide functional evidence for the presence of a peptide transporter on blood-ocular barriers and to elucidate the mechanism of a dipeptide transport across these barriers following systemic administration. Glycylsarcosine was chosen as a model dipeptide and [3H] glycylsarcosine was administered through the marginal ear vein of New Zealand white rabbits. At the end

Harisha Atluri; Banmeet S Anand; Jignesh Patel; Ashim K Mitra



Differences in amino acids composition and coupling patterns between mesophilic and thermophilic proteins  

Microsoft Academic Search

Summary.  Thermophilic proteins show substantially higher intrinsic thermal stability than their mesophilic counterparts. Amino acid\\u000a composition is believed to alter the intrinsic stability of proteins. Several investigations and mutagenesis experiment have\\u000a been carried out to understand the amino acid composition for the thermostability of proteins. This review presents some generalized\\u000a features of amino acid composition found in thermophilic proteins, including an

X.-X. Zhou; Y.-B. Wang; Y.-J. Pan; W.-F. Li



Fatty acid composition and regiodistribution in mare’s milk triacylglycerols at different lactation stages  

Microsoft Academic Search

The composition and regiodistribution of fatty acids influence the physical and the nutritional properties of milk fat. The\\u000a aim of this study was to determine the fatty acid composition and the triacylglycerols’ (TAGs) structure of mare’s milk collected\\u000a on days 20, 40, and 150 postpartum. Differences in the composition of fatty acids occurred between lactation times. A higher\\u000a proportion of saturated

Imen Haddad; Massimo Mozzon; Rosanna Strabbioli; Natale G. Frega



Structure of unsaturated vegetable oil glycerides: Direct calculation from fatty acid composition  

Microsoft Academic Search

Composition and structure of unsaturated glycerides of vegetable oils can be calculated directly from the fatty acid composition\\u000a of the oil. Fatty acid distribution on the 2 position as normally determined by lipase hydrolysis is calculated from the composition\\u000a of the whole oil by applying the following three rules in their respective order: Saturated fatty acids and those with chain

C. D. Evans; D. G. McConnell; G. R. List; C. R. Scholfield



Fatty acid composition of tissue lipids from miniature swine: Influence of dietary sucrose and starch  

Microsoft Academic Search

The fatty acid composition of serum, liver and adipose tissue from Pitman-Moore miniature swine was determined following their\\u000a consumption of starch- or sucrose-containing diets for a period of one year. Among the tissues studied there were no significant\\u000a differences in the fatty acid composition due to the type of dietary carbohydrate (starch or sucrose). The cholesteryl ester\\u000a fatty acid composition

Richard W. St. Clair



Effect of montmorillonite clay on flax fabric reinforced poly lactic acid composites with amphiphilic additives  

Microsoft Academic Search

Bio-composites (PF) were successfully prepared by reinforcing poly lactic acid (PLA) with woven flax fibers (F) in the presence of mandelic acid, benzilic acid, dicumyl peroxide (DCP) and zein as additives. To improve the mechanical properties of the bio-composites, montmorillonite clay (MMT) was also added. Characterizations of the bio-composites in presence and absence of MMT were performed by FTIR, DSC,

Rakesh Kumar; Mohammed K. Yakabu; Rajesh D. Anandjiwala



Hydrolysis of Protein and Model Dipeptide Substrates by Attached and Nonattached Marine Pseudomonas sp. Strain NCIMB 2021.  


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, we prepared a radiolabeled protein by 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-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. PMID:16348534

Griffith, P C; Fletcher, M



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

SciTech Connect

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.

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



Hydrolysis of Protein and Model Dipeptide Substrates by Attached and Nonattached Marine Pseudomonas sp. Strain NCIMB 2021 †  

PubMed Central

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, we prepared a radiolabeled protein by 14C-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-14C-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.

Griffith, Peter C.; Fletcher, Madilyn



The Prototype Dipeptide Gly-Gly a Rotational Study  

NASA Astrophysics Data System (ADS)

The simplest dipeptide Gly-Gly has been examined for the first time in the gas phase by laser ablation molecular beam Fourier transform microwave (LA-MB-FTMW) spectroscopy. The nuclear quadrupole hyperfine structure of two ^{14}N nuclei has been totally resolved allowing the conclusive identification of three conformers in the supersonic expansion. Intramolecular hydrogen bonding interactions have been analyzed on the bases of the structure of the observed conformers. Present results indicate that it is possible to face the study larger peptides using LA-MB-FTMW spectroscopy.

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



Demonstration of functional dipeptide transport with expression of PEPT2 in guinea pig cardiomyocytes.  


The transporters PEPT1 and PEPT2 accept a broad spectrum of substrates including small, naturally occurring peptides and peptidomimetic drugs. This study aimed to investigate for the first time whether these transporters are expressed and active in isolated cardiomyocytes. PEPT1/PEPT2 expression in rat kidney (positive control), guinea pig kidney and cardiomyocytes were investigated by reverse transcription polymerase chain reaction. L-Glycyl-L-[(14)C]sarcosine (Gly-sar) uptake was characterised using freshly isolated suspensions of adult male guinea pig cardiomyocytes. PEPT2-specific primers recognised mRNA of appropriate size and sequence in cardiomyocytes and kidney, whilst PEPT1 was expressed in the kidney only. The initial uptake (30 s) of 200 microM Gly-sar was dependent on extracellular pH with a maximum at pH 6.0 (237.8 +/- 12.2 pmol/microl) and a minimum at pH 8.0 (72.1 +/- 13.4 pmol/microl, n = 6 +/- SE, p < 0.01, T test). The K (m) and V (max) of Gly-sar uptake at pH 6.0 were 495.5 +/- 69.6 microM and 1470.5 +/- 69.6 pmol microl(-1) min(-1). The addition of 10 mM fosinopril, cefadroxil, carnosine, cyclacillin or a variety of L-amino acid containing dipeptides/tripeptides significantly reduced Gly-sar uptake. Gly-sar uptake was not affected by 10 mM D-ala-D-ala, glycine or sarcosine. These results support the presence of a functional dipeptide transporter in isolated cardiomyocytes, with accompanying expression of PEPT2. PMID:17120020

Lin, Hua; King, Nicola



Mutagenesis and Cysteine Scanning of Transmembrane Domain 10 of the Human Dipeptide Transporter  

PubMed Central

Purpose The human dipeptide transporter (hPEPT1) facilitates transport of dipeptides and drugs from the intestine into the circulation. The role of transmembrane domain 10 (TMD10) of hPEPT1 in substrate translocation was investigated using cysteine-scanning mutagenesis with 2-Trimethylammonioethyl methanethiosulfonate (MTSET). Methods Each amino acid in TMD10 was mutated individually to cysteine, and transport of [3H]Gly-Sar was evaluated with and without MTSET following transfection of each mutant in HEK293 cells. Similar localization and expression levels of wild type (WT) hPEPT1 and all mutants were confirmed by immunostaining and biotinylation followed by western blot analysis. Results E595C- and G594C-hPEPT1 showed negligible Gly-Sar uptake. E595D-hPEPT1 showed similar uptake to WT-hPEPT1, but E595K- and E595R-hPEPT1 did not transport Gly-Sar. Double mutations E595K/R282E and E595R/R282E did not restore uptake. G594A-hPEPT1 showed similar uptake to WT-hPEPT1, but G594V-hPEPT1 eliminated uptake. Y588C-hPEPT1 showed uptake of 20% that of WT-hPEPT1. MTSET modification supported a model of TMD10 with an amphipathic helix from I585 to V600 and increased solvent accessibility from T601 to F605. Conclusions Our results suggest that G594 and E595 in TMD10 of hPEPT1 have key roles in substrate transport and that Y588 may have an important secondary mechanistic role.

Xu, Liya; Haworth, Ian S.; Kulkarni, Ashutosh A.; Bolger, Michael B.; Davies, Daryl L.



Flax Fibers as Reinforcement in Poly (Lactic Acid) Biodegradable Composites  

NASA Astrophysics Data System (ADS)

In our research, poly (lactic acid) (PLA) film was used in combination with flax fibers as reinforcement to generate biodegradable composites by a film stacking technique and hot-press. The research of the relationship between the main process parameters and the performance of the board are done by the orthogonal experiments, then the various factors to influence the performance were analyzed and the optimal parameters were determined. The results showed that with the increasing of flax addition (30%~50%) and silane addition (1%~5%), the tensile strength and modulus increased, but the flexural strength and modulus increased then decreased with the increasing of flax addition (30%~50%). During the hot-press temperature (190°C~210°C) increasing, the tensile strength, flexural strength and modulus all increased. And the optimal parameters are determined by the flax addition 40%, silane addition 5%, hotpressing temperature 190°C, and hot-pressing time 3 min.

Yuan, Yuan; Guo, Minghui; Wang, Yong


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


Nile tilapia (Oreochormis niloticus) fishbone is a fish part with unknown composition. After elaboration of flour fishbone of tilapia it was analysede. The results in 100 g of flour were: moisture (14.2%), protein (40.8%), total lipids (25.3%), and ash (18.3%), and mineral (in 100 g) was 2715.9 mg (calcium), 1.3 mg (iron), and 1132.7 mg (phosphorus). A total of 22 fatty acids were detected in fishbone flour total lipids (TL), being the major ones in (g) of total lipids: 16:0 (208.5 mg); 18:1n-9 (344.3 mg); and 18:2n-6 (109.6 mg). The concentration of linolenic acid--LNA (18:3n-3); eicopentaenoic acid--EPA (20:5n-3), and docosahexaenoic acid--DHA (22:6n-3) were (29.9 mg), (3.3 mg), and (12.9 mg), respectively. The content to saturated (SFA) were (296.2 mg), monounsaturated (MUFA) 415.0 mg, and polyunsaturated (PUFA) 175.6 mg. The ratio PUFA:MUFA:SFA was 1:2.4:1.7, and the ratio omega-6/omega-3 fatty acids were 2.8. The last is within the recommended values. The results show low concentrations of omega-3 fatty acids in flour. The value caloric and calcium, iron, phosphorus, and protein content the fishbone flour of tilapia may results a valuable alternative food in the human diet. PMID:18589577

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



Effect of dietary fatty acid composition on fatty acid profiles of polar and neutral lipid tissue fractions in zebra finches, Taeniopygia guttata  

Microsoft Academic Search

The growing awareness that the fatty acid (FA) composition of the diets of birds, and ultimately their tissues, influence physiological performance variables, such as aerobic capacity, thermosensitivity, digestive efficiency, etc., underscores the need to understand how differences in dietary fatty acid composition actually translate into differences in the fatty acid composition of specific tissues. We quantified the fatty acid profiles

Marshall D. McCue; Oren Amitai; Inna Khozin-Goldberg; Scott R. McWilliams; Berry Pinshow



The Fatty Acid Composition of Subcutaneous, Omental and Inguinal Adipose Tissue in the Arctic Fox.  

National Technical Information Service (NTIS)

Fatty acid composition was investigated in the subcutaneous, omental and inguinal adipose tissue by means of flame detection gas chromatography. The monounsaturated and polyunsaturated fatty acids predominated in the subcutaneous adipose tissue, whereas t...

T. D. Shultz J. H. Ferguson



Ophthalmic compositions with an amphoteric surfactant and hyaluronic acid  

US Patent & Trademark Office Database

Ophthalmic compositions that comprise 0.1 ppm to 10 ppm of a cationic antimicrobial component selected from the group consisting of biguanides, polymeric biguanides, quaternium ammonium compounds and any one mixture thereof; 0.005 wt. % to 0.15 wt. % of hyaluronic acid; and 0.01 wt. % to 1.0 wt. % of an amphoteric surfactant of general formula I ##STR00001## wherein R.sup.1 is R or --(CH.sub.2).sub.n--NHC(O)R, wherein R is a C.sub.8-C.sub.16alkyl optionally substituted with hydroxyl and n is 2, 3 or 4; R.sup.2 and R.sup.3 are each independently selected from methyl, ethyl, propyl or iso-propyl; and R.sup.4 is a C.sub.2-C.sub.8alkylene optionally substituted with hydroxyl. The invention is also direct to the use of the ophthalmic compositions to clean and disinfect contact lenses, and in particular, soft, silicone hydrogel contact lenses.

Xia; Erning (Penfield, NY); Burke; Susan E. (Batavia, NY); Venkatesh; Srini (Pittsford, NY); Barniak; Vicki (Fairport, NY)



Principles of self-assembly of helical pores from dendritic dipeptides  

PubMed Central

The self-assembly of the dendritic dipeptides (4-3,4-3,5)nG2-CH2-Boc-l-Tyr-l-Ala-OMe and their achiral dendritic alcohol (4-3,4-3,5)nG2-CH2OH precursors, both with n = 1–16, where n represents the number of methylenic units in the alkyl groups of the dendron, are reported. All chiral dendritic dipeptides and achiral dendritic alcohols self-assemble into helical porous columns that are stable in both solution and solid state. The pore diameter (Dpore) of the columns self-assembled from dendritic dipeptides is ?10 Å larger than that of structures assembled from dendritic alcohols. The increase of the Dpore at the transition from dendritic alcohol to dendritic dipeptide is accompanied by a decreased solid angle of the building block. This trend is in agreement with previous pore size-solid angle dependences observed with different protective groups of the dipeptide and primary structures of the dendron. However, within the series of dendritic alcohols and dendritic dipeptides with various n, the Dpore increases when the solid angle increases. The results of these investigations together with those of previous studies on the role of dipeptide stereochemistry and protective groups on this self-assembly process provide the molecular principles required to program the construction of supramolecular helical pores with diameter controlled at the Å level from a single dendritic dipeptide architecture. These principles are expected to be valid for libraries of dendritic dipeptides based on dendrons and dipeptides with various primary structures.

Percec, Virgil; Dulcey, Andres E.; Peterca, Mihai; Ilies, Monica; Nummelin, Sami; Sienkowska, Monika J.; Heiney, Paul A.



Effect of cyanocobalamin and p -toluic acid on the fatty acid composition of Schizochytrium limacinum (Thraustochytriaceae, Labyrinthulomycota)  

Microsoft Academic Search

Changes in the fatty acid composition of docosahexaenoic acid (DHA)-producing Schizochytrium limacinum SR21 were investigated. The addition of cyanocobalamin, which is an active component of vitamin B12, decreased the content of odd-chain fatty acids such as pentadecanoic acid (C15:0) and heptadecanoic acid (C17:0). Cyanocobalamin\\u000a may upregulate the cobalamin-dependent methylmalonyl-CoA mutase, which converts propionic acid to succinic acid, thereby decreasing\\u000a the

Norifumi Shirasaka; Yukari Hirai; Haruka Nakabayashi; Hajime Yoshizumi



Proton conductivity of phosphoric acid doped polybenzimidazole and its composites with inorganic proton conductors  

Microsoft Academic Search

Phosphoric acid doped polybenzimidazole (PBI) and PBI composite membranes have been prepared in the present work. The PBI composites contain inorganic proton conductors including zirconium phosphate (ZrP), (Zr(HPO4)2·nH2O), phosphotungstic acid (PWA), (H3PW12O40·nH2O) and silicotungstic acid (SiWA), (H4SiW12O40·nH2O). The conductivity of phosphoric acid doped PBI and PBI composite membranes was found to be dependent on the acid doping level, relative humidity

Ronghuan He; Qingfeng Li; Gang Xiao; Niels J. Bjerrum



Chemical characteristics, fatty acid composition and conjugated linoleic acid (CLA) content of traditional Greek yogurts.  


Many studies with conjugated linoleic acid (CLA) indicate that it has a protective effect against mammary cancer. Because dairy products are the most important dietary sources of CLA, we have investigated the CLA concentrations and additionally the fatty acid profiles and chemical composition of several commercial, traditional, Greek yogurts from different geographical origin. The fat content of yogurts was in the order of goatacids (SFA) were found in low-fat yogurts, of monounsaturated fatty acids (MUFA) in sheep milk yogurts and of polyunsaturated fatty acid (PUFA) in low-fat cow milk yogurts. PMID:23442628

Serafeimidou, Amalia; Zlatanos, Spiros; Laskaridis, Kostas; Sagredos, Angelos



Extractable Lipids of Gram-Negative Marine Bacteria: Fatty - Acid Composition  

Microsoft Academic Search

Fatty-acid compositions were determined for 20 strains of marine and estuarine bacteria and two strains representative of terrestrial species. Results showed that the fatty acids of marine bacteria differed little from those of nonmarine organisms, and a primary role for hexadecenoic acid was indicated. Of the 20 strains examined, with the exception of one, the major fatty-acid species were C



Amino acid composition and the evolutionary rates of protein-coding genes  

Microsoft Academic Search

Summary Based on the rates of amino acid substitution for 60 mammalian genes of 50 codons or more, it is shown that the rate of amino acid substitution of a protein is correlated with its amino acid composition. In particular, the content of glycine residues is negatively correlated with the rate of amino acid substitution, and this content alone explains

Dan Graur



The fatty acid composition of milk fat as influenced by feeding oilseeds  

Microsoft Academic Search

The fatty acid composition of bovine milk fat can be substantially altered by feeding lipid sources which alter the fatty acid profile of lipid entering the intestine from the rumen. As long-chain fatty acids of dietary origin can be incorporated directly into milk fat the opportunity exists to alter the ratio of short and long-chain fatty acids as well as

John J. Kennelly



Variation in amino acid composition of cytochrome c of species in the fungal genus Ustilago  

Microsoft Academic Search

Cytochrome c was extracted and purified from nine species of the genusUstilago, representing five pathogen for monocotyledonous and four for dicotyledonous host species. The amino acid compositions of acid hydrolysates of cytochrome c from these species were compared and divergence values were calculated for all pairs of species. Aspartic acid, serine, glutamic acid, proline, glycine, alanine, valine, leucine, phenylalanine, lysine,

Oscar H. Will III



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

Microsoft Academic Search

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

A. M. Skelley; J. R. Scherer; A. D. Aubrey; R. H. Ivester; P. Ehrenfreund; F. J. Grunthaner; J. L. Bada; R. A. Mathies



Improving fatty acid composition in peanuts (Arachis hypogaea) by SNP genotyping and traditional breeding.  

Technology Transfer Automated Retrieval System (TEKTRAN)

Fatty acid composition is an important seed quality trait in cultivated peanuts (Arachis hypogaea L.). Monounsaturated fats, such as oleic acid (C18:1), an omega-9 fatty acid, has been shown to have beneficial effects on human health. In addition, peanuts bred to produce high levels of oleic acid ...


Fatty Acid Composition of Commercial Spanish Fast Food and Snack Food  

Microsoft Academic Search

Fatty acid composition, total fat contents and percentages of saturated (SFA), monounsaturated (MFA), polyunsaturated (PUFA) and trans isomers of fatty acids (t FA) were analysed in commercial Spanish fast food and snack food by capillary gas chromatography (CGC) using a capillary column. The results obtained show a great variability in the percentages of fatty acids (g\\/100 g total fatty acids)

P. Mario Fernández; San Juan



Dipeptide synthesis and separation in a reversed micellar membrane reactor.  


The synthesis of dipeptide AcPheLeuNH2 catalyzed by alpha-chymotrypsin encapsulated in TTAB/octanol/heptane reversed micelles was investigated in a tubular ceramic membrane reactor, operated in a batch mode. The reaction medium conditions (TTAB concentration, buffer molarity, and pH) were optimized using a factorial design in order to achieve maximum synthesis rates. Hydrated reversed micelles permeated through the membrane together with the substrate ester, dipeptide, and by-products. However, as a result of the low solubility of the peptide in the reaction medium, selective precipitation occurred, thus enabling the complete retention of the solid product by the ultrafiltration membrane and therefore an integration of a separation step in the biotransformation process. In spite of the continuous accumulation of solids inside the reactor, constant permeation flow rates could be maintained throughout the operation. The influence of alpha-chymotrypsin, TTAB, and water concentration on the kinetics and mass transfer of the system was also investigated. The behavior of the system during a continuous experiment was also evaluated. PMID:7765651

Serralheiro, M L; Prazeres, D M; Cabral, J M



Theoretical UV circular dichroism of aliphatic cyclic dipeptides.  


Four cyclic dipeptides (piperazine-2,5-diones), cyclo(L-Pro-Gly), cyclo(L-Pro-L-Leu), cyclo(L-Ala-L-Ala), and cyclo(L-Pro-L-Ala), were modeled from crystal structure data. Conformations resulting from energy minimization using molecular mechanics were compared with traditional ab initio and density functional theory geometric optimizations for each dipeptide. In all computational cases, the gas phase was assumed. The pi-pi transition feature of the UV circular dichroic (CD) spectra was predicted for each peptide structure via the classical dipole interaction model. The dipole interaction model predicted CD spectra that qualitatively agreed with experiment when MP2 or DFT geometries were used. By coupling MP2 or DFT geometric optimizations with the classical physics method of the dipole interaction model, significantly better CD spectra were calculated than those using geometries obtained by molecular mechanics. Thus, one can couple quantum mechanical geometries with a classical physics model for calculation of circular dichroism. PMID:16839074

Carlson, Kristine L; Lowe, Stephen L; Hoffmann, Mark R; Thomasson, Kathryn A



Association between Plasma Nonesterified Fatty Acids Species and Adipose Tissue Fatty Acid Composition.  


Fatty acid composition of adipose tissue (AT) is an established long-term biomarker for fatty acid (FA) intake and status, but AT samples are not easily available. Nonesterified FA composition in plasma (pNEFA) may be a good indicator of AT FA composition, because pNEFA are mainly generated by AT lipolysis. We investigated the correlation of 42 pNEFA and subcutaneous as well as visceral AT FA in 27 non-diabetic women with a median BMI of 36 kg/m(2) (Q0.25: 25 kg/m(2); Q0.75: 49 kg/m(2)). Close correlations of pNEFA and AT FA were found for odd-chain FA (15?0 r?=?0.838 and 0.862 for subcutaneous and visceral AT, respectively) and omega-3 FA (22?6 r?=?0.719/0.535), while no significant or low correlations were found for other FA including 18?1 (r?=?0.384/0.325) and 20?4 (r?=?0.386/0.266). Close correlations of pNEFA and AT FA were found for essential fatty acids, like 18?2 (r?=?0.541/0.610) and 20?5 (r?=?0.561/0.543). The lower correlation for some pNEFA species with AT FA indicates that the variation of most pNEFA is significantly affected by other FA sources and flux of FA to tissue, in addition to release from AT. A relevant influence of BMI on the level of correlation was shown for saturated FA. NEFA analysis in fasted plasma can serve as a virtual AT biopsy for some FA, and as a biomarker for intake of dairy products and sea fish. PMID:24098359

Hellmuth, Christian; Demmelmair, Hans; Schmitt, Isabel; Peissner, Wolfgang; Blüher, Matthias; Koletzko, Berthold



Association between Plasma Nonesterified Fatty Acids Species and Adipose Tissue Fatty Acid Composition  

PubMed Central

Fatty acid composition of adipose tissue (AT) is an established long-term biomarker for fatty acid (FA) intake and status, but AT samples are not easily available. Nonesterified FA composition in plasma (pNEFA) may be a good indicator of AT FA composition, because pNEFA are mainly generated by AT lipolysis. We investigated the correlation of 42 pNEFA and subcutaneous as well as visceral AT FA in 27 non-diabetic women with a median BMI of 36 kg/m2 (Q0.25: 25 kg/m2; Q0.75: 49 kg/m2). Close correlations of pNEFA and AT FA were found for odd-chain FA (15?0 r?=?0.838 and 0.862 for subcutaneous and visceral AT, respectively) and omega-3 FA (22?6 r?=?0.719/0.535), while no significant or low correlations were found for other FA including 18?1 (r?=?0.384/0.325) and 20?4 (r?=?0.386/0.266). Close correlations of pNEFA and AT FA were found for essential fatty acids, like 18?2 (r?=?0.541/0.610) and 20?5 (r?=?0.561/0.543). The lower correlation for some pNEFA species with AT FA indicates that the variation of most pNEFA is significantly affected by other FA sources and flux of FA to tissue, in addition to release from AT. A relevant influence of BMI on the level of correlation was shown for saturated FA. NEFA analysis in fasted plasma can serve as a virtual AT biopsy for some FA, and as a biomarker for intake of dairy products and sea fish.

Hellmuth, Christian; Demmelmair, Hans; Schmitt, Isabel; Peissner, Wolfgang; Bluher, Matthias; Koletzko, Berthold



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

PubMed Central

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.

Streeter, John G.



Texture of Butter from Cows with Different Milk Fatty Acid Compositions1  

Microsoft Academic Search

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

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



Phenolic acid induced growth of gold nanoshells precursor composites and their application in antioxidant capacity assay  

Microsoft Academic Search

In the present work, the gold nanoshells (GNSs) precursor composites were preadsorbed onto the surface of ITO substrates. With the treatment of modified electrodes immersed in the gold nanoparticles (GNPs) growth solution containing different phenolic acids, the GNSs precursor composites were enlarged to varying degrees. Phenolic acids with one or more phenolic hydroxyl groups served as reductants for the growth

Xiaoyuan Ma; Weiping Qian




Technology Transfer Automated Retrieval System (TEKTRAN)

This study was designed to evaluate biochemical changes in the fatty acid (FA) compositions of selected lipid depot (kidney and liver) and absorption (intestine) organs in larvae and metamorphosing sea lamprey, Petromyzon marinus. The results indicated that changes in the fatty acid composition of t...


Subchronic antipsychotic drug treatment does not alter brain phospholipid fatty acid composition in rats  

Microsoft Academic Search

Altered membrane phospholipid fatty acid composition is reported in schizophrenia and appears to be reduced by antipsychotic drug treatment. To determine whether antipsychotic drugs have a direct effect on brain phospholipid fatty acid composition, the effects of sub-chronic treatment with a “typical” and an “atypical” antipsychotic drug were determined in adult male Sprague–Dawley rats. Rats were treated with haloperidol (1

Beth Levant; Jennifer F. Crane; Susan E. Carlson



Determination of the S isotope composition of methanesulfonic acid.  


Sulfur (S) isotopes have been used to apportion the amount of biogenic and anthropogenic sulfate in remote environments, an important parameter that is used to model the global radiation budget. A key assumption in the apportionment calculations is that there is little isotope selectivity as reduced compounds such as dimethyl sulfide (DMS) are oxidized. This paper describes a method to determine, for the first time, the S isotope composition of methanesulfonic acid (MSA), the product of DMS oxidation. The isotope composition of MSA was measured directly by EA-IRMS and was used as an isotope reference for the method. Synthetic mixtures approximating the conditions expected for aerosol MSA samples were prepared to test this method. First, MSA solutions were measured alone and then in combination with MSA and SO4(2-). In synthetic mixtures, SO4(2-) was separated from MSA by precipitating it as BaSO4 prior to preparation of MSA for isotope analysis. The delta 34S value for MSA solutions was -2.6 per thousand (SD +/- 0.4 per thousand), which is not different from the delta 34S obtained from MSA filtrate after precipitating SO4(2-) from the mixture (-2.7 +/- 0.3 per thousand). However, these values are offset from direct EA-IRMS analysis of MSA used as the isotope reference by -1.1 +/- 0.2 per thousand, and this must be accounted for in reporting MSA measurements. The S isotope measurements using this method approach a limiting value above 300 microg of MSA. This is approximately equal to the MSA found in 20,000 m3 of air, assuming ambient concentrations of approximately 15 ng m(-3). Three samples of MSA from the Pacific Ocean measured using this technique have an average delta 34S value of +17.4 +/- 0.7 per thousand. PMID:16841918

Sanusi, Astrid A; Norman, Ann-Lise; Burridge, Carolyn; Wadleigh, Moire; Tang, Wing-Wai



Influence of fatty acid profile of total parenteral nutrition emulsions on the fatty acid composition of different tissues of piglets.  


Total parenteral nutrition (TPN) studies in human babies of very-low-birth-weight suggest that the lipid emulsions currently available are not optimum for neonatal nutrition. Since fatty acid metabolism in human and pigs is very similar, the present study examines how lipid emulsions used in clinical TPN (i.e. ClinOleic, Intralipid, Lipofundin or Omegaven), with different fatty acid compositions, administered to neonatal piglets for 7 days, influenced their tissue fatty acid composition as compared to those enterally fed with a sow milk replacer. A positive linear relationship was found between the proportion of all individual fatty acids in the lipid emulsions or in the milk replacer versus those in plasma, skeletal muscle, subcutaneous fat, liver, heart, pancreas, stomach or intestine total lipids or in brain phospholipids, the latter showing the lowest correlation coefficient. With the exception of brain, the proportion of either oleic acid or alpha-linolenic acid in the individual tissues was correlated with those present in the corresponding lipid emulsion or milk replacer, whereas the proportion of linoleic acid correlated significantly with all the tissues studied. With the exception of brain phospholipids, both eicosapentaenoic and docosahexaenoic acids were higher in the tissues of piglets receiving Omegaven than in all other groups. In conclusion, with the exception of the brain, fatty acid composition of plasma and different tissues in piglets are strongly influenced by the fatty acid profile of TPN emulsions. Fatty acid composition of brain phospholipids are, however, much less influenced by dietary composition, indicating an active and efficient metabolism that ensures its appropriate composition at this key stage of development. PMID:18491157

Amusquivar, E; Sánchez, M; Hyde, M J; Laws, J; Clarke, L; Herrera, E



Amino acid nitrogen isotopic composition patterns in lacustrine sedimenting matter  

NASA Astrophysics Data System (ADS)

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.

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



Effects of broodstock dietary lipid on fatty acid compositions of eggs from sea bass ( Dicentrarchus labrax)  

Microsoft Academic Search

Samples of sea bass (Dicentrarchus labrax) eggs from broodstock which had been fed either a formulated pelleted feed, containing fish and corn oil, or a local trash fish, bogue (Boops boops) were analysed for lipid class compositions, fatty acid compositions of phosphatidylcholine (PC), phosphatidylethanolamine (PE) and phosphatidylinositol (PI) and wax ester and fatty alcohol compositions of wax esters. The pelleted

J. Gordon Bell; Bruce M. Farndale; Michael P. Bruce; Jose M. Navas; Manuel Carillo



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

Microsoft Academic Search

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

Ruihua Hu; Jae-Kyoo Lim



Effects of n-3 polyunsaturated fatty acid supplementation in pregnancy on maternal and fetal erythrocyte fatty acid composition  

Microsoft Academic Search

Objective: The aim of this study was to assess the effects of fish oil supplementation in pregnancy on maternal erythrocyte fatty acid composition at different stages of pregnancy and in the post-partum period, and on neonatal erythrocyte fatty acid composition.Design: A double-blind, randomised, placebo-controlled study.Setting: Subiaco, Western Australia.Subjects: In all, 98 women booked for delivery at St John of God

J A Dunstan; T A Mori; A Barden; L J Beilin; P G Holt; P C Calder; A L Taylor; S L Prescott



Seasonal Variations in Fatty Acid Composition and the N-6\\/N-3 Fatty Acid Ratio of Pikeperch (Sander LUCIOPERCA) Muscle Lipids  

Microsoft Academic Search

Total lipid, fatty acid composition and the N-6\\/N-3 fatty acid ratios of muscle of pikeperch (Sander lucioperca) was determined once every two months. The ratio of unsaturated fatty acids (UFA) was higher than half of the total fatty acid content, and the monounsaturated fatty acid (MUFA) was higher than the polyunsaturated fatty acid (PUFA) ratio. The n-3 fatty acids were

Kazim Uysal; M. Yasar Aksoylar



The effect of dietary fatty acid composition on liver retinyl ester (vitamin A ester) composition in the rat.  


The dependence of liver retinyl ester (vitamin A ester) composition on dietary fatty acid composition was studied in rats. Weanling male Sprague-Dawley rats were fed purified test diets containing 8% of one of 10 test triglycerides (either tributyrin, tricaproin, tricaprylin, tricaprin, trilaurin, trimyristin, tripalmitin, tristearin, triolein, trilinolein) or corn oil (a mixed triglyceride) for 23 d after an initial 1-wk stabilization period. Essential fatty acids were provided by safflower oil (8 g/kg diet). Total liver fatty acid composition showed the expected responses to dietary fatty acid intake; short-chain and medium-chain fatty acids were readily elongated to palmitate and stearate, and palmitate and stearate were readily desaturated. Consumption of oleate or linoleate (as their triglycerides) markedly enriched their concentrations in liver lipids. The proportions of palmitate were generally greater in liver retinyl esters than in total liver fatty acids, and the proportions of oleate were less. However, retinyl ester composition was significantly affected by dietary triglyceride, particularly by diets providing long-chain fatty acids. Total liver vitamin A levels were depressed in the group fed trilinolein. PMID:2703916

Furr, H C; Clifford, A J; Smith, L M; Olson, J A



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


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. The highest success rate using the jackknife test obtained through SVM is 86.01%. 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 PMID:21110985

Hayat, Maqsood; Khan, Asifullah



Antarctic fish tubulins: heterogeneity, structure, amino acid compositions and charge.  


1. Tubulins purified from the brain tissues of three Antarctic fishes (Notothenia gibberifrons, Notothenia coriiceps neglecta, and Chaenocephalus aceratus) contain equimolar quantities of the alpha and beta chains and are free of microtubule-associated proteins (MAPs) and other non-tubulin proteins. 2. When examined by isoelectric focusing and by two-dimensional electrophoresis, brain tubulins from the Antarctic fishes were found to be highly heterogeneous; each was resolved into 15-20 distinct variants. The range of isoelectric points displayed by the Antarctic fish tubulins (5.30-5.75) is slightly more basic than that of bovine brain tubulin (5.25-5.60). 3. Peptide mapping demonstrated that tubulins from the Antarctic fishes and the cow differ in structure. 4. The amino acid compositions of piscine and mammalian tubulins are similar, but the Antarctic fish tubulins apparently contain fewer glutamyl and/or glutaminyl residues than do tubulins from the temperate channel catfish (Ictalurus punctatus) and the cow. 5. Native tubulin from N. coriiceps neglecta possesses 1-2 fewer net negative charges per tubulin dimer than does bovine tubulin. 6. We suggest that the enhanced assembly of Antarctic fish tubulins at low temperatures (-2 to +2 degrees C) results from adaptive, perhaps subtle, changes in their tubulin subunits. PMID:3180738

Detrich, H W; Overton, S A



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

Microsoft Academic Search

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

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



Composition and metabolism of fatty acids in phospholipids of density-separated red cells of rats  

Microsoft Academic Search

Fatty acid compositions of phosphatidylcholine (PC) and phosphatidylethanolamine (PE) and the rates of fatty acid esterification\\u000a to these phospholipids (PL) were measured in intact rat red cell populations of different ages separated by density gradient\\u000a centrifugation in order to clarify changes in membrane lipids of red blood cells during in vivo aging. Fatty acid compositions\\u000a of PC and PE altered

Manabu Kunimoto; Kunimitsu Kaya; Takashi Miura



Hydrofluoric acid-resistant composite window and method for its fabrication  


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.

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



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

Microsoft Academic Search

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

F. J. Bavelaar; A. C. Beynen



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

NASA Astrophysics Data System (ADS)

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).

Erkan, Nuray; Özden, Özkan



Familial aggregation of red blood cell membrane fatty acid composition: the Kibbutzim Family Study  

Microsoft Academic Search

The fatty acid composition of membranes plays an important role in health and diseases. Whether genetic factors play a role in interindividual variability in membrane fatty acid levels has received limited attention. Using variance decomposition methods, we estimated the heritability of red blood cell (RBC) membrane fatty acids in an unselected population sample of 80 families (205 male and 212

Rozenn N. Lemaitre; David S. Siscovick; Elliot M. Berry; Jeremy D. Kark; Yechiel Friedlander



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...


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

Microsoft Academic Search

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

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



Stable carbon isotope composition of amino acids in modern and fossil Mercenaria  

Microsoft Academic Search

Amino acids were extracted from the bivalve shells of modern and fossil Mercenaria and analyzed for ?13C (PDB). These data were then compared to the expected impacts of diagenesis and contamination on the isotopic composition of fossilized proteins. The ?13C of l-amino acids from modern specimens had enriched glycine, glutamic acid, and isoleucine relative to leucine, and phenylalanine. The range

Thomas H. O’Donnell; Stephen A. Macko; John F. Wehmiller



Static CP 31P NMR multilamellar bilayer broadlines in the absence and presence of the bioactive dipeptide ?-Ala-Tyr or Glu  

NASA Astrophysics Data System (ADS)

Static CP 31P 1H NMR experiments of DPPC/H2O multilamellar bilayers in the absence or presence of the dipeptide ?-Ala-Tyr or the amino acid Glu were performed. The broadline 31P spectrum of the DPPC bilayers was perturbed more in the Glu-containing samples than those with ?-Ala-Tyr. A novel simulation approach of the NMR broadline shapes simplifying the dynamical framework of the system was applied in order to compare the conformation of the gel and the liquid crystalline phases of DPPC bilayers alone or after the incorporation of either the dipeptide ?-Ala-Tyr or Glu. The experimental NMR spectra were in agreement with fast overall rotational diffusion of the phospholipid macromolecules about an axis tilted with respect to the normal of the bilayer, and immobilized lamellar structures. Comparison of the structural parameters obtained from the simulations of the experimental NMR spectra of the DPPC bilayer samples without and with Glu showed that it interacts strongly with the headgroup. The dipeptide was on the other hand not interacting as strongly with the phosphate as the Glu, indicating that it was not located in the vicinity of the phosphate group.

Benetis, Nikolas-Ploutarch; Kyrikou, Ioanna; Zervou, Maria; Mavromoustakos, Thomas



Serum Paraoxonase 1 Activity Is Associated with Fatty Acid Composition of High Density Lipoprotein  

PubMed Central

Introduction. Cardioprotective effect of high density lipoprotein (HDL) is, in part, dependent on its related enzyme, paraoxonase 1 (PON1). Fatty acid composition of HDL could affect its size and structure. On the other hand, PON1 activity is directly related to the structure of HDL. This study was designed to investigate the association between serum PON1 activity and fatty acid composition of HDL in healthy men. Methods. One hundred and forty healthy men participated in this research. HDL was separated by sequential ultracentrifugation, and its fatty acid composition was analyzed by gas chromatography. PON1 activity was measured spectrophotometrically using paraxon as substrate. Results. Serum PON1 activity was directly correlated with the amount of stearic acid and dihomo-gamma-linolenic acid (DGLA). PON1/HDL-C was directly correlated with the amount of miristic acid, stearic acid, and DGLA and was inversely correlated with total amount of ?6 fatty acids of HDL. Conclusion. The fatty acid composition of HDL could affect the activity of its associated enzyme, PON1. As dietary fats are the major determinants of serum lipids and lipoprotein composition, consuming some special dietary fatty acids may improve the activity of PON1 and thereby have beneficial effects on health.

Boshtam, Maryam; Pourfarzam, Morteza; Ani, Mohsen; Naderi, Gholam Ali; Basati, Gholam; Mansourian, Marjan; Dinani, Narges Jafari; Asgary, Seddigheh; Abdi, Soheila



The opt1 gene of Drosophila melanogaster encodes a proton-dependent dipeptide transporter.  


We have cloned and characterized the opt1 gene of Drosophila melanogaster. This gene encodes a protein with significant similarity to the PTR family of oligopeptide transporters. The OPT1 protein is localized to the apical epithelial membrane domains of the midgut, rectum, and female reproductive tract. The opt1 message is maternally loaded into developing oocytes, and OPT1 is found in the alpha-yolk spheres of the developing embryo. It is also found throughout the neuropil of the central nervous system, with elevated expression within the alpha- and beta-lobes of the mushroom bodies. Transport activity was examined in HeLa cells transiently expressing OPT1. This protein is a high-affinity transporter of alanylalanine; the approximate Km constant is 48.8 microM for this substrate. OPT1 dipeptide transport activity is proton dependent. The ability of selected beta-lactams to inhibit alanylalanine transport suggests that OPT1 has a broad specificity in amino acid side chains and has a substrate requirement for an alpha-amino group. Together these data suggest an important role for OPT1 in regulating amino acid availability. PMID:9730971

Roman, G; Meller, V; Wu, K H; Davis, R L



Effect of extraction methods on lipid yield and fatty acid composition of lipid classes containing ?-linolenic acid extracted from fungi  

Microsoft Academic Search

The effect of extraction procedures on the lipid yield and fatty acid composition of total lipid and main lipid structures\\u000a (phospholipids, diacylglycerols, triacylglycerols, free fatty acids, and sterol esters) of fungal biomass (Mucor mucedo CCF-1384) containing ?-linolenic acid (GLA) was investigated. Seventeen extraction methods, divided into three groups, were\\u000a tested: six with chloroform\\/methanol, five with hexane\\/alcohols, and six with common

Milan ?ertík; Peter Andráši; Ján Šajbidor



Thermomechanical properties of stereoblock poly(lactic acid)s with different PLLA\\/PDLA block compositions  

Microsoft Academic Search

Stereoblock poly(lactic acids) (sb-PLAs), having abundant enantiomeric compositions of poly(l-lactic acid) (PLLA), were successfully synthesized by solid-state polycondensation (SSP) of the melt blends of medium molecular weight prepolymers: both PLLA and poly(d-lactic acid) (PDLA) that had primarily been prepared by melt-polycondensation. The molecular weight of the resultant PLLA-rich sb-PLA was effectively enhanced by the dehydrative coupling of abundant PLLA molecules

Masayuki Hirata; Yoshiharu Kimura



Fatty acid composition of the red blood cell membrane in relation to menopausal status.  


PURPOSE: Menopausal status effects female anatomical functioning at a variety of system-wide and cellular levels, including cellular membrane composition. This study analyzed a nested case-control ORDET data set of 433 pre and post-menopausal breast cancer controls to examine the effects of menopausal status on the fatty acid composition of the red blood cell membrane.METHODS: ORDET is a prospective cohort study conducted in Italy to investigate the etiologic role of hormones and diet in breast cancer development. The fatty acid composition was measured and analyzed by gas chromotography, comparing retention time with standard measurement. Twenty-two individual fatty acids were measured, recorded, and categorized into four fatty acid groups: saturated, monounsaturated, polyunsaturated n-6 (PUFA n-6), and polyunsaturated (PUFA n-3) fatty acids.RESULTS: Post-menopausal women had consistently lower mean values for all four fatty acid categories and all individual fatty acids. Statistically significant mean differences, by menopausal status, were observed for three of the four fatty acid categories: saturated fatty acids (p = 0.006), PUFA n-6 acids (p = 0.001), and PUFA n-3 acids (p = 0.000). The biggest statistically significant differences in mean values among individual fatty acids for each category were observed for Palmitic acid (p = 0.009), Oleic acid (p = 0.040), Linoleic acid (p = 0.000), and Docosahexaenoic acid (p = 0.000). Individual fatty acids were also less highly correlated among post-menopausal women.CONCLUSIONS: There was an observed relationship between menopausal status and the fatty acid composition of the red blood cell membrane that warrants further study. This relationship may contribute to the physiological and psychological changes that occur during and after menopause, and may have far-reaching implications for women's health. PMID:11018419

Tworek; Muti; Micheli; Krogh; Riboli; Berrino



3H-L-leucine transport by the promiscuous crustacean dipeptide-like cotransporter.  


The crustacean intestine and hepatopancreas display a variety of solute transport mechanisms for transmembrane transfer of dietary contents from lumen to epithelial cytosol. An in vitro intestinal perfusion apparatus was used to characterize mucosal to serosoal (MS) and serosal to mucosal (SM) Zn(2+) -dependent (3)H-L-leucine transport by the intestine of the American lobster, Homarus americanus. Transmural 20?µM MS (3)H-L-leucine fluxes across lobster intestine were a hyperbolic function of luminal zinc concentration (1-50?µM) following Michaelis-Menten kinetics (K(m) = 2.67 ± 0.74?µM; J(max) = 19.56 ± 2.22?pmol/cm(2) ×min). Transmural 20?µM SM (3)H-L-leucine fluxes were not affected by serosal zinc, resulting in a highly significant stimulation of net amino acid transfer to the blood by luminal metal. MS fluxes of 20?µM (3)H-L-leucine were also hyperbolic functions of luminal [Cu(2+)], [Mn(2+)], [Na(+)], and [H(+)]. MS flux of (3)H-L-leucine was a sigmoidal function of luminal [L-leucine] and was stimulated by the addition of 20?µM luminal zinc at both pH 7.0 and 5.5. A greater enhanced amino acid transport occurred at the lower pH 5.5. MS flux of 20?µM (3)H-L-leucine in the presence of 20?µM zinc was significantly inhibited by addition of 100?µM luminal glycylsarcosine, and MS flux of 20?µM (3)H-glycylsarcosine was inhibited by 100?µM L-leucine in the presence of 20?µM zinc. Results suggest that (3)H-L-leucine and metals form a complex (e.g., Leu-Zn-Leu] that may functionally mimic dipeptides and use a dipeptide-like transporter during MS fluxes as suggested for fish and mammals. PMID:21732547

Obi, I; Wells, A L; Ortega, P; Patel, D; Farah, L; Zanotto, F P; Ahearn, G A



The fatty acid composition of a Vibrio alginolyticus associated with the alga Cladophora coelothrix . Identification of the novel 9-methyl-10-hexadecenoic acid  

Microsoft Academic Search

The fatty acid composition of a new strain of Vibrio alginolyticus, found in the alga Cladophora coelothrix, was studied. Among 38 different fatty acids, a new fatty acid, 9-methyl-10-hexadecenoic acid and the unusual 11-methyl-12-octadecenoic\\u000a acid, were identified. Linear alkylbenzene fatty acids, such as 10-phenyldecanoic acid, 12-phenyldodecanoic acid and 14-phenyltetradecanoic\\u000a acid, were also found in V. alginolyticus. The alga contained 43%

Néstor M. Carballeira; Anthony Sostre; Kamen Stefanov; Simeon Popov; Athanas Kujumgiev; Stefka Dimitrova-Konaklieva; Carmen G. Tosteson; Thomas R. Tosteson



[The changes in contents and composition of phenolic acids during cell xylem growth in scots pine].  


The contents and composition of alcohol soluble phenolic acids were studied during cell xylem growth in the course of wood annual increment formation in the stems of Scots pine. The cells of cambium zone, of two stages of expansion growth and the outset of secondary thickening zone (before lignification) were successively gathered from the stem segments of 25-old pine trees in the period of earlywood xylem formation with constant anatomical and histochemical control. The contents of free and bound forms of phenolic acids, isolated by 80% ethanol from tissues, as well as of their ethers and esters were calculated both per dry weight and per cell. The content and relation of the fractions and the composition of phenolic acid have been found to change significantly from cambium zone to the outset of tracheid secondary thickening. The character of the variations depends on a calculation method. According to the calculation per cell the amount of free and bound phenolic acids and in their composition of esters and especially ethers increased at the first step of expansion growth zone, decreased at the second one and rose again in the outset of secondary wall deposition. In dependence on the stage of cell development the pool of bound phenolic acids exceeded of free acid pool in 2-5 times. Sinapic and ferulic acids dominated in the composition of free hydroxycinnamic acids. The content and composition of hydroxycinnamic acids in ethers and esters depended on cell development phase. In cambium p-coumaric and sinapic acids were principal aglycons in ethers, at other stages these were sinapic and caffeic acids. The esters in cambium zone included essentially p-coumaric acid and at the other stages - sinapic and ferulic acids. At the first phase of growth benzoic acid was connected principally by ester bonds. The pool of these esters decreased from the first phase of growth to the outset of cell wall thickening and in proportion to this the level of free benzoic acid rose. PMID:21950053

Antonova, G F; Zheliznichenko, T V; Stasova, V V


The gross chemical composition and fatty acid composition of 18 species of tropical Australian microalgae for possible use in mariculture  

Microsoft Academic Search

The gross chemical composition and fatty acid composition of 18 species of tropical Australian microalgae (2 cryptomonads, 8 diatoms, 3 prasinophytes, 4 prymnesiophytes and a rhodophyte) grown under standard conditions (pH 8.3±0.2, temperature 25±1°C, photon flux density 80±2 ? mol m?2 s?1 and salinity 25±1‰ and harvested in late log phase of growth), were determined as part of a program

Susan M Renaud; Luong-Van Thinh; David L Parry



Oxidative stability of purified canola oil triacylglycerols with altered fatty acid compositions as affected by triacylglycerol composition and structure  

Microsoft Academic Search

Canola oil triacylglycerols from genetically modified canola lines (InterMountain Canola Co., Cinnaminson, NJ) have been evaluated\\u000a for their photooxidative and autoxidative stabilities, as influenced by their fatty acid compositions and their triacylglycerol\\u000a compositions and structures. Purified canola oil triacylglycerols were oxidized in duplicate in fluorescent light at 25°C\\u000a and in the dark at 60°C under oxygen, and their oxidative deterioration

W. E. Neff; T. L. Mounts; W. M. Rinsch; H. Konishi; M. A. El-Agaimy



Manipulation of Fatty Acid Composition in Animal Cells Grown in Culture*  

PubMed Central

The fatty acid composition of animal cells cultured in serum-free medium can be manipulated when the synthesis of endogenous fatty acids is inhibited by a biotin analog and fatty acids are supplied in the medium as detergent esters of Tween. When mouse LM cells were grown in medium supplemented with Tween-19:0 (an ester of Tween and nonadecanoic acid), odd chain fatty acid content of cellular phospholipids and neutral lipids increased from 1% to 75%. Concurrently, the saturated fatty acid content increased from 27% to 85%. Similar alterations in fatty acid content have been observed when BHK21 cells are subjected to the same enrichment regime. The ability to control the fatty acid composition of cultured animal cells is a prerequisite to investigations into the role of the membrane lipid physical state in processes unique to these cells. Images

Wisnieski, Bernadine J.; Williams, Robert E.; Fox, C. Fred



Sulfonated mesoporous silica-carbon composites and their use as solid acid catalysts  

NASA Astrophysics Data System (ADS)

The synthesis of highly functionalized porous silica-carbon composites made up of sulfonic groups attached to a carbon layer coating the pores of three types of mesostructured silica (i.e. SBA-15, KIT-6 and mesocellular silica) is presented. The synthesis procedure involves the following steps: (a) removal of the surfactant, (b) impregnation of the silica pores with a carbon precursor, (c) carbonization and (d) sulfonation. The resulting silica-carbon composites contain ˜30 wt % of carbonaceous matter with a high density of acidic groups attached to the deposited carbon (i.e.sbnd SO3H, sbnd COOH and sbnd OH). The structural characteristics of the parent silica are retained in the composite materials, which exhibit a high surface area, a large pore volume and a well-ordered porosity made up uniform mesopores. The high density of the sulfonic groups in combination with the mesoporous structure of the composites ensures that a large number of active sites are easily accessible to reactants. These sulfonated silica-carbon composites behave as eco-friendly, active, selective, water tolerant and recyclable solid acids. In this study we demonstrate the usefulness of these composites as solid acid catalysts for the esterification of maleic anhydride, succinic acid and oleic acid with ethanol. These composites exhibit a superior intrinsic catalytic activity to other commercial solid acids such as Amberlyst-15.

Valle-Vigón, Patricia; Sevilla, Marta; Fuertes, Antonio B.



Fatty acid composition of lipid classes in maternal and cord plasma at birth  

Microsoft Academic Search

The fatty acid composition of plasma phospholipids, triglycerides, cholesterol esters and nonesterified fatty acids was determined\\u000a by high-resolution capillary gas-liquid chromatography in 41 pairs of mothers and their term infants at time of birth. The\\u000a total free fatty acid content in maternal and cord plasma was positively correlated, possibly reflecting a passive, gradient\\u000a dependent transplacental passage of nonesterified fatty acids.

T. M. Berghaus; H. Demmelmair; B. Koletzko



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

Microsoft Academic Search

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

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



Amino Acid Composition of Proteins: Selection against the Genetic Code  

Microsoft Academic Search

Distribution of amino acids in 68 representative proteins is compared with their distribution among 61 codons of the genetic code. Average amounts of lysine, aspartic acid, glutamic acid, and alanine are above the levels anticipated from the genetic code, and arginine, serine, leucine, cysteine, proline, and histidine are below such levels. Arginine plus lysine account for 11.0 percent of codons

Thomas H. Jukes; Richard Holmquist; Herbert Moise



Effect of treatment with electrolyzed NaCl solutions and essential oil compounds on the proximate composition, amino acid and fatty acid composition of carp fillets  

Microsoft Academic Search

This investigation was undertaken to evaluate the effect of treatment with electrolyzed NaCl solutions and 1% essential oil (0.5% carvacrol+0.5% thymol) on the proximate composition and nutritional components (amino acids and fatty acids) of carp fillets at room temperature (25°C). Carp fillet samples were treated with anodic electrolyzed NaCl solution [EW (+)], cathodic electrolyzed NaCl solution [EW (?)] followed by

Barakat S. M. Mahmoud; Y. Kawai; K. Yamazaki; K. Miyashita; T. Suzuki



Glutamine-containing dipeptides as infusion substrates in the septic state.  


Recently a relationship has been postulated between lowered intracellular glutamine concentrations in the skeletal muscle and the rate of protein synthesis. We investigated the effect of 48 hours of parenteral nutrition supplemented with a solution containing glutamine in free or dipeptide form (alanylglutamine or glycylglutamine) on the intracellular glutamine pool in skeletal muscle and on the hind limb exchange of glutamine in dogs with sepsis after surgery. Before surgery, dogs were fasted for 48 hours. We used glutamine dipeptides as sources because they remain stable in an aqueous solution. Nutrition solutions were isocaloric (17.8 kcal/kg body weight/day on day 1 and 35.6 kcal/kg on day 2) and isonitrogenous (0.33 gm nitrogen/kg body weight/day), providing 2.6 mmol/kg body weight/day as glutamine source. During starvation, muscular free glutamine levels decreased by 41% to 10.4 mmol/L (p less than 0.001). On the second postoperative day the dogs had lowered plasma protein levels, a sharp drop in platelet count, an increase in the leukocyte count, and positive blood cultures. None of the solutions investigated in this study was effective in repleting the glutamine pool during 2 days of postoperative nutrition (11 +/- 2.0 mmol/L without glutamine, 10.3 +/- 2.2 mmol/L with glutamine plus alanine, 9.9 +/- 1.6 mmol/L with alanylglutamine, 7.5 +/- 1.1 mmol/L with glutamine plus glycine, and 7.2 +/- 1.2 mmol/L with glycylglutamine, respectively). The release of glutamine from the hindquarter was 631 +/- 38 nmol/kg body weight/min in the control group and decreased significantly in dogs receiving alanylglutamine (13.5 +/- 45 nmol/kg body weight/min; p less than 0.001) or the constituent amino acids (265 +/- 66 nmol/kg body weight/min; p less than 0.01) but was unchanged in dogs receiving glycylglutamine or glutamine plus glycine. We conclude that the duration and dosage of glutamine administration (equivalent to 26 gm glutamine per day in a patient weighing 70 kg) used in this study are not sufficient to restore glutamine deficiency of the skeletal muscle in the depleted state. PMID:2510334

Karner, J; Roth, E; Ollenschläger, G; Fürst, P; Simmel, A; Karner, J



Process for Preserving Raw Fruits and Vegetables Using Ascorbic Acid Esters and Compositions Thereof.  

National Technical Information Service (NTIS)

The invention relates to the preservation of raw fruits, vegetables and their juices. More particularly, the invention relates to the use of certain ascorbic acid esters, and compositions thereof, to control enzymatic browning in raw fruit and vegetable p...

G. M. Sapers K. B. Hicks P. A. Seib



Therapeutic and Diagnostic Methods and Compositions Based on Notch Proteins and Nucleic Acids  

National Technical Information Service (NTIS)

The present invention relates to therapeutic and diagnostic methods and compositions based on Notch proteins and nucleic acids. The invention provides for treatment of disorders of cell fate or differentiation by administration of a therapeutic compound o...

C. M. Blaumueller P. Zagouras R. G. Fehon S. Artavanis-Tsakonas



Process for Preserving Raw Fruits and Vegetables Using Ascorbic Acid Esters and Compositions Thereof.  

National Technical Information Service (NTIS)

The present invention relates to the preservation of raw fruits, vegetables and their juices. More particularly, the present invention relates to the use of certain ascorbic acid esters, and compositions thereof, to control enzymatic browning in raw fruit...

G. M. Sapers K. B. Hicks P. A. Seib



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...


Experimental protein and energy deficiencies: effects on brain free amino acid composition in rats.  


1. The effects of protein-energy malnutrition on brain free amino acids of acidic and neutral groups were investigated in experimental rats. 2. Severe energy restriction did not modify the free amino acid composition of the brain while protein deficiency affected certain amino acids of the brain in opposite directions. Significant decreases in the levels of aspartic acid, threonine and tyrosine were observed in the protein-deficient rats. 3. These changes in brain amino acids appear to be specific to protein deficiency and not affected by energy deficiency. PMID:407922

Kaladhar, M; Rao, B S



Effects of ambient temperature on lipid and fatty acid composition in the oviparous lizards, Phrynocephalus przewalskii  

Microsoft Academic Search

This study was designed to assess the effect of ambient temperature on lipid content, lipid classes and fatty acid compositions of heart, liver, muscleandbraininoviparouslizards,Phrynocephalusprzewalskii,caughtinthedesertareaofChina.Significantdifferencescouldbeobserved in the contents of the total lipid and fatty acid compositions among different temperatures (4, 25 and 38 -C). The study showed that liver and muscle were principal sites of lipid storage. Triacylglycerol (TAG) mainly deposited

Jian-Min Shen; Ren-De Li; Fei-Yun Gao


Proximate composition and fatty acid profile of Bombyx mori L. chrysalis toast  

Microsoft Academic Search

The objective of the present study was to analyze the nutritional composition of Bombyx mori (L.) chrysalis (worm) toast. The results have revealed that this sub-product of the silk thread industry is a rich source of protein (51.1%); lipid (34.4%); essential fatty acids such as the linolenic acid (C18: 3n-3, 24.4%); zinc (244?gg?1) and potassium (4.77mgg?1). The composition of this

Nadia R. Pereira; Osvaldo Ferrarese-Filho; Makoto Matsushita; Nilson E. de Souza



Fatty acid compositions of arthropod and cephalopod photoreceptors: interspecific, seasonal and developmental studies  

Microsoft Academic Search

Fatty acid compositions of the compound eyes of insects (soldier-bug, Hemiptera, and silk moth, Lepidoptera), crustaceans\\u000a (crayfish and grapsid crab, Decapoda) and inner and outer segments of visual cells of a squid (Cephalopoda, Mollusca) were\\u000a analyzed by gaschromatography for interspecific comparison. Fatty acid compositions showed great variation among species.\\u000a In insect compound eyes, 16:0 and 18:0 were the main saturated

E. Eguchi; Y. Ogawa; K. Okamoto; K. Mochizuki



Lipid Composition in the Classification of the Butyric Acid-producing Clostridia  

Microsoft Academic Search

An examination of 20 strains of butyric acid-producing Clostridium species for phospholipid class compositions, plasmalogen content, and acyl and alk-1-enyl chains showed that the deoxyri bonucleic acid homology groups I (Clostridium butyricum) and I1 (Clostridium beijerinckii) could be distinguished by their lipid compositions. The phospholipids of C. butyricum strains had ethanolamine as the major nitrogenous lipid polar head-group moiety, more




The fatty acid composition of cottonseed oil at various stages of solvent extraction  

Microsoft Academic Search

The variation in the fatty acid composition of the glyceride portion of cottonseed oil at various stages of solvent extraction\\u000a has been investigated. Prime cottonseed meats were flaked and extracted in glassware rate extraction apparatus, using commercial\\u000a hexane up to different degrees of extractions. The fatty acid composition of cottonseed oil obtained after extracting the\\u000a flakes to different residual oil

Lionel K. Arnold; R. Basu Roy Choudhury



Immunostimulant activities of a lipophilic muramyl dipeptide derivative and of desmuramyl peptidolipid analogs.  

PubMed Central

The immunostimulant properties of a new muramyl dipeptide (MDP) derivative bearing a lipophilic moiety on the C-terminal end of the peptide chain are described. It is shown, in particular, that 1,O-(acetylmuramyl-L-alanyl-D-isoglutamine-L-alanyl)-glycerol-3-mycolate had increased immunostimulant activity in comparison with MDP. It induced hypersensitivity even when administered with an antigen in saline, and it gave higher protection against bacterial infections than did MDP. A quite unexpected finding was obtained with the corresponding desmuramyl compound 1,O-(L-alanyl-D-isoglutamine-L-alanyl)-glycerol-3-mycolate, which had no activity in producing humoral antibodies but was just as active as the muramic acid-containing compound in stimulating nonspecific resistance to bacterial infections. It was not pyrogenic. Modifications of the peptide moiety or the lipid moiety of this peptidolipid led to decrease, or even loss, of activity. These results show the importance of the N-acetylmuramyl moiety in MDP for humoral antibody production. The peptidolipid 1,O-(L-alanyl-D-isoglutamine-L-alanyl)-glycerol-3-mycolate is the first member of a new category of nonspecific immunostimulants.

Parant, M A; Audibert, F M; Chedid, L A; Level, M R; Lefrancier, P L; Choay, J P; Lederer, E



Utilization of dipeptides by the caprine mammary gland for milk protein synthesis.  


Specific use by the mammary gland in vivo of amino acids (AA) of peptide origin has been demonstrated in lactating dairy goats using a dual-labeled tracer technique involving close-arterial (external pudic artery, EPA) infusion of 13C-labeled dipeptides. The extent of utilization does not appear to differ for glycyl-L-[1-13C]phenylalanine and glycyl-L-[1-13C]leucine, perhaps indicative of a common mechanism by which AA are incorporated from peptide into milk protein. [1-13C]phenyl-alanine of peptide origin appears to be concentrated within the red blood cell, suggesting a role for the erythrocyte in peptide metabolism in vivo. In conclusion, it appears that the lactating mammary gland of goats has the ability to utilize AA of peptide origin for milk protein synthesis, and while the mechanism by which [1-13C]AA are incorporated into milk protein is not clear, it may involve peptide hydrolysis by either mammary cell surface or red blood cell hydrolases followed by uptake of liberated AA by the mammary gland. PMID:8048612

Backwell, F R; Bequette, B J; Wilson, D; Calder, A G; Metcalf, J A; Wray-Cahen, D; MacRae, J C; Beever, D E; Lobley, G E



Characterization and Differentiation of Filamentous Fungi Based on Fatty Acid Composition  

PubMed Central

Cellular fatty acid composition of 100 different filamentous fungi, including oomycetes, zygomycetes, ascomycetes, basidiomycetes, and sterile mycelia, was analyzed to determine if they can be differentiated from one another on this basis and how minor variations in culture temperature and age affect this characteristic. Many fungi were found to possess the same fatty acids but produced different relative concentrations of each. Some fungi differed in both the fatty acids produced and in the relative concentrations of others. Multivariate discriminant analysis demonstrated that all of the species included in this study had significantly different (P < 0.001) fatty acid profiles. Each of the three phyla from which representative species were analyzed and the sterile forms had distinctive fatty acid profiles. Significant differences in fatty acid composition were also found at the intraspecific level. Both culture temperature and age affected fatty acid composition in the fungi examined, but when these factors were held constant, variance in fatty acid composition was not a problem and fungal fatty acid profiles could be differentiated statistically.

Stahl, P. D.; Klug, M. J.



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

SciTech Connect

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.

Lambert, R.M.



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

Microsoft Academic Search

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

F. Glasser; A. Ferlay; Y. Chilliard



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

Microsoft Academic Search

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

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




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...


Polyaniline-doped benzene sulfonic acid\\/epoxy resin composites: structural, morphological, thermal and dielectric behaviors  

Microsoft Academic Search

Conducting polymer composites, which are simply physical mixtures of an insulating polymer matrix and intrinsically conducting polymers, are promising new materials for various applications such as antistatic coatings, shielding and electromagnetic absorbers. In this context, a novel conducting composite was successfully produced. It is based on epoxy resin and polyaniline (PANI) doped in benzene sulfonic acid, which was used as

Belkacem Belaabed; Saad Lamouri; Nacera Naar; Patrice Bourson; Sidi Ould Saad Hamady



Storage of polyacid-modified resin composites (“compomers”) in lactic acid solution  

Microsoft Academic Search

Objectives: The aim of this study was to determine the interaction of four polyacid-modified resin composites with aqueous lactic acid solutions, and to compare changes with those for a glass-ionomer cement and a conventional resin composite.Methods: For each material, namely Compoglass F, Dyract AP, Hytac and Ana Compomer, plus AquaCem (glass-ionomer cement) and Pekafil (conventional composite resin), five cylindrical specimens

J. W. Nicholson; B. J. Millar; B. Czarnecka; H. Limanowska-Shaw



Base Composition of Deoxyribonucleic Acid Isolated From Cariogenic Streptococci.  

National Technical Information Service (NTIS)

The guanine-cytesine composition was determined for DNA isolated from nine cariogenic streptococcal strains. Cells briefly exposed to penicillin during growth were lysed by treatment with lysozyme followed by sodium lauryl sulphate. Guanine-cytesine compo...

A. L. Coykendall



Trans Fatty Acids and Fatty Acid Composition of Mature Breast Milk in Turkish Women and Their Association with Maternal Diet’s  

Microsoft Academic Search

The aim of this study was to determine the fatty acid composition and trans fatty acid and fatty acid contents of breast milk in Turkish women and to find the effect of breastfeeding mothers’ diet\\u000a on trans fatty acid and fatty acid composition. Mature milk samples obtained from 50 Turkish nursing women were analyzed. Total milk\\u000a lipids extracts were transmethylated

Gülhan Samur; Ali Topcu; Semra Turan



Influence of Fatty Acid Profile of Total Parenteral Nutrition Emulsions on the Fatty Acid Composition of Different Tissues of Piglets  

Microsoft Academic Search

Total parenteral nutrition (TPN) studies in human babies of very-low-birth-weight suggest that the lipid emulsions currently\\u000a available are not optimum for neonatal nutrition. Since fatty acid metabolism in human and pigs is very similar, the present\\u000a study examines how lipid emulsions used in clinical TPN (i.e. ClinOleic, Intralipid, Lipofundin or Omegaven), with different\\u000a fatty acid compositions, administered to neonatal piglets

E. Amusquivar; M. Sánchez; M. J. Hyde; J. Laws; L. Clarke; E. Herrera



trans fatty acids, 5. Fatty acid composition of lipids of the brain and other organs in suckling piglets  

Microsoft Academic Search

The effects of dietarytrans fatty acids on the fatty acid composition of the brain in comparison with other organs were studied in 3-wk-old suckling\\u000a piglets. In Experiment (Expt.) 1 the piglets were delivered from sows fed partially hydrogenated fish oil (PHFO) (28%trans), partially hydrogenated soybean oil (PHSBO) (36%trans) or lard (0%trans). In Expt. 2 the piglets were delivered from sows

Jan Pettersen; Johannes Opstvedt



Ontogenetic trends in aspartic acid racemization and amino acid composition within modern and fossil shells of the bivalve Arctica  

Microsoft Academic Search

Ontogenetic trends (umbo to growth edge of shell) in aspartic acid (Asp) racemization and amino acid composition and their evolution over time are examined in serial samples of annual growth bands from a time-series of three live-collected and two fossil (ca. 500 and 1000 y BP) shells of the long-lived bivalve Arctica islandica. The rate of Asp racemization is shown

Glenn A Goodfriend; Christopher R Weidman



Effect of acidic conditions on fatty acid composition and membrane fluidity of Escherichia coli strains isolated from Crescenza cheese  

Microsoft Academic Search

The effect of low pH on minimum pH, growth kinetics and adaptive response to acidity conditions were studied on nineEscherichia coli strains having food origin and two collection strains. Moreover, the effects of low pH on the modification of fatty acid\\u000a (FA) composition and membrane fluidity of the strains were studied. Also the effects of a pre-adaptation to pH 5

Andrea Gianotti; Luciana Iucci; Maria Elisabetta Guerzoni; Rosalba Lanciotti



Group composition of carboxylic acids from West Siberian crude oils  

Microsoft Academic Search

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

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



Influences of low salinity and dietary fatty acids on fatty acid composition and fatty acid desaturase and elongase expression in red sea bream Pagrus major  

Microsoft Academic Search

This study investigated the effects of dietary fatty acids and water salinity on fatty acid composition and expression of\\u000a the fatty acid desaturase (fads)-like and elongase (elovl)-like genes of red sea bream Pagrus major. Sequence and phylogenetic analyses revealed that the fads-like and elovl-like genes isolated in this study encoded fads6 and elovl5, respectively. There was no significant difference in

Yoji Yamamoto; Yutaka Haga; Misako Miwa; Goro Yoshizaki; Shuichi Satoh



Conjugated linoleic acids alter bone fatty acid composition and reduce ex vivo prostaglandin E 2 biosynthesis in rats fed n-6 or n-3 fatty acids  

Microsoft Academic Search

This study evaluated the effects of conjugated linoleic acids (CLA) on tissue fatty acid composition and ex vivo prostaglandin E2 (PGE2) production in rats given diets varying in n-6 and n-3 fatty acids. Four groups of rats were given a basal semipurified diet\\u000a (AIN-93G) containing 70 g\\/kg of added fat for 42 d. The fat treatments were formulated to contain

Yong Li; Bruce A. Watkins



Modification of fatty acid composition of lipid accumulating yeasts with cyclopropene fatty acid desaturase inhibitors  

Microsoft Academic Search

The effect of cyclopropene fatty acids, sterculic and malvalic, on the lipids of yeasts grown under nitrogen limiting, lipid accumulating, conditions was studied. The ratio of stearic to oleic acid showed a dose response effect, with an increase in stearic acid content as the dose of cyclopropene fatty acid increased, and a corresponding reduction in oleic acid. Linoleic and linolenic

R. S. Moreton



Influence of Tween 80 on the mycolic acid composition of three cutaneous corynebacteria.  


Changes in the mycolic acid composition of three cutaneous strains of corynebacteria were caused by the addition of Tween 80 to the culture medium. Gas chromatography-mass spectrometry showed that the carbon chain length and the degree of unsaturation had been affected: the levels of corynomycolic acid with 36 carbon atoms and two double bonds increased significantly. PMID:3254943

Chevalier, J; Pommier, M T; Cremieux, A; Michel, G



Fatty acid composition of the infusorian Paramecium caudatum and Colpoda steini (Ciliophora type)  

Microsoft Academic Search

phospho- and phosphonolipids include up to 83% of eicosatetraenoic acid [3]. At the present time, the genus Paramecium includes more than i0 species, but the lipid and fatty acid compositions of only two of them have been studied: P. aurelia and P. tetraurelia [3, 6]. Biomass from the Kuibyshev reservoir (region of the Institute of Ecology of the Volga Basin

V. M. Dembitskii; N. I. Zharikova



Fatty acid composition and rheological behaviour of prickly pear seed oils  

Microsoft Academic Search

Prickly pear fruits constituted valuable foodstuff for humans and animals in arid and semi-arid regions. Two species of prickly pear from Tunisia, Opuntia ficus indica and Opuntia stricta, were investigated for fatty acid composition and physicochemical parameters of the seed oil. No significant difference in either physical or chemical parameters was found between the species. The main fatty acids of

Monia Ennouri; Bourret Evelyne; Mondolot Laurence; Attia Hamadi



Effect of dietary sources of roasted oilseeds on blood parameters and milk fatty acid composition  

Microsoft Academic Search

The aim of this experiment was to investigate the effect of supplementing the basal diet with oilseeds on blood parameters and composition of milk fatty acids, especially conjugated linoleic acid (CLA). Forty-eight lactating Holstein cows in early lactation were used in a randomized block design. The cows in each group were fed the control basal diet (the control diet) or

Z. L. Liu; D. P. Yang; P. Chen; S. B. Lin; X. Y. Jiang; W. S. Zhao; J. M. Li; W. X. Dong



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

Microsoft Academic Search

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

Rafael Nafikov



Effect of Dietary Canola on Fatty Acid Composition of Bovine Adipose Tissue, Muscle, Kidney, and Liver  

Microsoft Academic Search

The purpose of this study was to determine effects of feeding canola and soybean products as protein supplements on fatty acid composi- tion of adipose tissue and muscle of slaughter bulls and steers and on fatty acid composition of kidney and liver total lipids of bulls. Products included canola meal (CM), extruded canola (EC, full-fat), ground canola (GC, full-fat), soybean

J. R. Busboom; C. J. Kercher



Carbohydrate and amino acid composition of dissolved organic matter leached from soil  

Microsoft Academic Search

Low molecular weight organic substances (LMWOS) in soil and soil solution include mainly amino acids, carboxylic acids, and carbohydrates. Due to their high bioavailability they play a crucial role in the cycles of C and nutrients in soils. The variety of soil processes that involve LMWOS requires identifying their composition to elucidate reactions and transformations. In most studies, LMWOS are

Holger Fischer; Axel Meyer; Klaus Fischer; Yakov Kuzyakov



Separation, isolation, and amino acid composition of the albumin-like fraction from psoriatic scales  

Microsoft Academic Search

The albumin-like fraction of psoriatic scales was isolated either directly by slab gel electrophoresis or after previous treatment with polyethylene glycol6000. After both isolation procedures the amino acid composition was determined. Both proteins were rich of glutamic acid, glycine, and alanine. On the other hand both contained very smal amounts of cysteine and tyrosine. Only after the direct isolation procedure

F. Jochen Förster; Karin Gottschalk; Gottfried Leonhardi; Lütje Behnken; Erika Grosshans



Potential Relationships Between Fatty Acid Compositions and Phytochemicals of Selected Low Linolenic Soybeans Grown in Maryland  

Microsoft Academic Search

Eight soybean genotypes grown in Maryland were analyzed for total phenolic content, antioxidant capacity, isoflavone composition,\\u000a lutein content, tocopherol composition, and fatty acid profile. The soybean samples consisted of seven low ?-linolenic (18:3n-3)\\u000a genotypes and 1 standard genotype for comparison. 18:3n-3 levels were positively correlated with palmitic acid (16:0) content,\\u000a and negatively correlated with oleic acid (18:1n-9) concentration. Daidzein and

Monica Whent; Margaret Slavin; William Kenworthy; Liangli Yu



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

NASA Astrophysics Data System (ADS)

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.

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



Oil Content and Fatty Acid Composition in Seeds of Three Safflower Species  

Microsoft Academic Search

Seeds of six safflower (C. tinctorius L.) genotypes and 19 accessions of two wild species were analyzed for oil and fatty acid composition. Oil content ranged\\u000a from 29.20 to 34.00, 20.04 to 30.80 and 15.30 to 20.80% in C. tinctorius, C. oxyacantha Bieb. and C. lanatus L., respectively. The main fatty acids of oleic, linoleic, palmitic and stearic acids composed

Mohammad R. Sabzalian; Ghodratollah Saeidi; Aghafakhr Mirlohi



Amino Acid and Vitamin Composition of Raw and Cooked Horse Mackerel  

Microsoft Academic Search

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

Nuray Erkan; Arif Selçuk; Özkan Özden



The Amino Acid Composition of Whole Sorghum Grain in Relation to Its Nitrogen Content  

Microsoft Academic Search

Cereal Chem. 65(4):271-277 Sorghum grains (12 samples from seven different lines or hybrids) with phenylalanine, and glutamine plus glutamic acid, remained constant for total nitrogen, N, content ranging from 1.5 to 3 g\\/ 100 g grain dry matter serine, tyrosine, tryptophan, and asparagine plus aspartic acid, and were accurately analyzed for their amino acid composition from six decreased for the



Protein Content and Amino Acid Composition in Grains of Wheat-Related Species  

Microsoft Academic Search

The protein content and amino acid composition for 17 wheat-related species (WRS) and three common wheats (control) were determined and analyzed, and the essential amino acids (EAAs) in WRS were evaluated according to FAO\\/WHO amino acid recommendations. The results showed that the mean protein content for WRS was 16.67%, which was 23.21% higher than that for the control. The mean

Xiao-ling JIANG; Ji-chun TIAN; Zhi HAO; Wei-dong ZHANG



Explaining longevity of different animals: is membrane fatty acid composition the missing link?  

Microsoft Academic Search

Saturated and monounsaturated fatty acids are very resistant to peroxidative damage, while the more polyunsaturated a fatty\\u000a acid, the more susceptible it is to peroxidation. Furthermore, the products of lipid peroxidation can oxidatively damage other\\u000a important molecules. Membrane fatty acid composition is correlated with the maximum lifespans of mammals and birds. Exceptionally\\u000a long-living mammal species and birds have a more

A. J. Hulbert



Fatty Acid Composition of Three Marine Fishes of the Bay of Bengal  

Microsoft Academic Search

Oil samples collected from three fishes namely Sting Ray (Dasyatis uarrnak), Anchovy (Setipinna taty), and Eel (Congresox talabonoides) from the Bay of Bengal were analyzed to determine their fatty acid composition with the aid of Gas Liquid Chromatography (GLC). The saturated fatty acid contents were 52.95, 45.28 and 52.29 %; and the unsaturated fatty acid contents were 43.97, 54.72 and

Habibur R. Bhuiyan; K. K. Nath; P. Seal; Mir Ezharul Hossain



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

SciTech Connect

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.

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



Slightly modifying pseudoproline dipeptides incorporation strategy enables solid phase synthesis of a 54 AA fragment of caveolin-1 encompassing the intramembrane domain.  


This work contributes to highlight the benefits of pseudoproline dipeptides introduction in difficult SPPS. We show how a slight modification in the positioning choice conditioned the synthesis achievement of a 54 amino acid long caveolin-1 peptide encompassing the intramembrane domain. Furthermore, we report a side reaction correlated with the coupling steps and generating truncated fragments with a mass deviation of + 42 Da. Considering the need of structural data for membrane proteins, most of which are considered as prevalent therapeutic targets, chemical synthesis provides an interesting alternative pathway to obtain hydrophobic domains by pushing back the frontiers of conventional RP methods of purification. PMID:20014324

Coïc, Yves-Marie; Lan, Charlotte Le; Neumann, Jean-Michel; Jamin, Nadège; Baleux, Françoise



Reworking of amino acid in marine sediments: Stable carbon isotopic composition of amino acids in sediments along the Washington coast  

Microsoft Academic Search

The stable carbon isotopic composition of nine individual amino acids were investigated in phytoplankton and zooplankton, estuarine plankton, terrigenous material, marine fecal material, and clay mineral isolates collected along the Washington coast. The clay fraction was isolated from suspended sediments of the Columbia River (the mineral source) and three shelf and slope stations (mineral deposition sites). In the sediments, terrigenous

Richard G. Keil; Marilyn L. Fogel



Thermal analysis of microwave assisted synthesized poly(acrylic) acid/alumina composites.  

NASA Astrophysics Data System (ADS)

The preparation of poly (acrylic acid)/ alumina composites has been done using microwave polymerization. Pure alumina samples and alumina doped with copper were prepared using hydrothermal method. Glass transition temperature (Tg) of the PAA/alumina composites was determined using DSC analysis. Melting of all the PAA/alumina composites was observed around 235 °C. Thermal stability was verified using TGA analysis. It reveals that these composites are thermally stable up to 240 °C. SEM was used to study the surface morphology of polymer samples. The presence of both alumina and copper content has been found to affect glass transition temperature.

Desai, Rahul; Tomar, Laxmi J.; Chakrabarty, Bishwajit S.



Phagocytosis of hybrid molecular nanosomal compositions containing oxidized dextrans conjugated with isonicotinic acid hydrazide by macrophages.  


We studied phagocytic activity of macrophages towards hybrid molecular nanosomal compositions consisting of 150-800-nm nanoliposomes containing oxidized dextrans with a molecular weight of 35 and 60 kDa obtained by chemical ("permanganate") and radiochemical oxidation of dextran conjugated with isonicotinic acid hydrazide (dextrazides, intracellular prolonged antituberculous drugs). Phagocytic activity of macrophages towards hybrid molecular nanosomal compositions containing dextrazides obtained by chemical oxidation of dextrans is higher than activity towards hybrid molecular nanosomal compositions containing dextrazides prepared by radiochemical oxidation and depends on the size of hybrid molecular nanosomal compositions and molecular weight of oxidized dextrans. PMID:21116494

Shkurupy, V A; Arkhipov, S A; Troitsky, A V; Luzgina, N G; Zaikovskaja, M V; Ufimceva, E G; Iljine, D A; Akhramenko, E S; Gulyaeva, E P; Bistrova, T N



Chemical composition of acid rains in the Venezuelan savannah region  

Microsoft Academic Search

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 \\

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



Influence of biodegradation on crude oil acidity and carboxylic acid composition  

Microsoft Academic Search

Quantitative analysis of separated carboxylic acid fractions of 33 crude oils from the UK, Italy and California, showed that the carboxylic acid fraction is a major factor responsible for the acidity in these oils. It was apparent that biodegradation is the main process that produces high concentrations of carboxylic acids in these crude oils with the extent of biodegradation, as

W Meredith; S.-J Kelland; D. M Jones



Effects of various levels of conjugated linoleic acid supplementation on fatty acid content and carcass composition of broilers.  


The effects of dietary conjugated linoleic acid (CLA) supplementation on growth performance, carcass quality, free fatty acid composition, and accumulation of CLA were investigated in broilers. Four hundred eighty 3-wk-old broilers were assigned to 4 dietary treatments (0, 0.5, 1.0, and 1.5% CLA) with 6 replicates of 20 chickens. Feed consumption and BW were recorded at every 5-d period. On d 42, carcass compositions were determined from 30 birds per treatment. There were no significant differences in average daily feed intake among the treatments. However, feed conversion ratio was highly significantly different (P < 0.01) between treatments, and average daily gain was significantly reduced by a supplement of dietary CLA (P < 0.05). Live weight and percentages of carcass, drumstick, thigh, boneless thigh, pectoralis major, and pectoralis minor were not influenced by the dietary CLA. Abdominal fat was significantly reduced (P < 0.01) with the increased CLA level in the broilers' diets. Percentages of liver weight were significantly increased (P < 0.01) after the CLA treatments. Percentages of drumstick and boneless drumstick were significantly decreased (P < 0.05) by dietary CLA. In terms of free fatty acid composition in broiler meat, CLA addition significantly increased (P < 0.05) saturated fatty acids, especially in thigh muscle, whereas unsaturated fatty acids were unchanged. Accumulations of CLA in meat were significantly increased (P < 0.05) with increasing CLA level in the diet. PMID:17234845

Suksombat, W; Boonmee, T; Lounglawan, P



Amino acid composition of bulk protein and salt relationships of selected enzymes of Salinibacter ruber , an extremely halophilic bacterium  

Microsoft Academic Search

The extremely halophilic bacterium Salinibacter ruber was previously shown to have a high intracellular potassium content, comparable to that of halophilic Archaea of the family Halobacteriaceae. The amino acid composition of its bulk protein showed a high content of acidic amino acids, a low abundance of basic amino acids, a low content of hydrophobic amino acids, and a high abundance

Aharon Oren; Lili Mana



Seasonal Changes of Fatty Acid Compositions in Overwintering Larvae of Rice Stem Borer, Chilo suppressalis (Lepidoptera: Pyralidae)  

Microsoft Academic Search

Cold acclimation and overwintering state can affect fatty acid compositions of insects. To determine compositional change of fatty acids during nondiapause and diapause stages, an experiment was conducted to investigate fatty acid constituents from whole body of C. suppressalis larvae. Five most abundant fatty acids were found to be palmitoleic (35–58%), palmitic (18–44%), oleic (14–23%), stearic (0.5–2.5%) and linoleic acid

Maryam Atapour; Saeid Moharramipour; Mohsen Barzegar



Fatty acid, polar lipid and wall amino acid composition of Gardnerella vaginalis  

Microsoft Academic Search

Representative strains of Gardnerella vaginalis were degraded using both an alkaline and an acid methanolysis and the fatty acid methyl esters released examined by thin-layer and gas chromatography. The profiles obtained were both qualitatively and quantitatively similar and were comprised of straight chain saturated and unsaturated non-hydroxylated fatty acids with hexadecanoic acid (16:0) and octadecenoic acid (18:1) the major components.

A. G. O'Donnell; D. E. Minnikin; M. Goodfellow; P. Piot



Night temperature affects fatty acid composition in sunflower oil depending on the hybrid and the phenological stage  

Microsoft Academic Search

Fatty acid composition is affected by plant genotype and environmental conditions with temperature a major effect. The effect of night temperature during different periods of fruit filling on the fatty acid composition of sunflower oil from hybrids with different potential oleic acid content has never been studied. This information is needed if we are further to improve oil quality. A

N Izquierdo; L Aguirrezábal; F Andrade; V Pereyra



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

Microsoft Academic Search

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



Composition of fatty acids triacylglycerols and unsaponifiable matter in Calophyllum calaba L. oil from Guadeloupe.  


The composition of the kernel oils of two Calophyllum species (Calophyllum calaba L. and Calophyllum inophyllum L.) was investigated. The physico-chemical properties and fatty acid composition of the kernel oils were examined. In two species, oleic acid C18:1 (39.1-50%) is the dominating fatty acid followed by linoleic acid C18:2 (21.7-31.1%) as the second major fatty acid. Stearic C18:0 (13.4-14.3%) and palmitic C16:0 (11-13.7%) acids are the major saturates. The oils contains an appreciable amount of unsaturated fatty acids (70.8-73.10%). Most of the fatty acids are present as triacylglycerol (76.7-84%), twenty one triacylglycerols are detected with predominantly unsaturated triacylglycerols. The total unsaponifiable content, its general composition and the identity of the components of the sterol and tocopherol fractions are presented. In both species, analysis of the unsaponifiable fractions revealed the preponderance of phytosterols, mainly stigmasterol (35.8-45.1%) and beta-sitosterol (41.1-43.1%). Among the eight tocopherols and tocotrienols present in two species, variations exist; alpha-tocopherol (183 mg/kg) is the main tocopherol in Calophyllum calaba L. and Delta-tocotrienol (236 mg/kg) is the dominant tocotrienol in Calophyllum inophyllum L. PMID:16045947

Crane, Sylvie; Aurore, Guylène; Joseph, Henry; Mouloungui, Zéphirin; Bourgeois, Paul



Conjugated linoleic acid changes swine performance and carcass composition  

Microsoft Academic Search

ABSTRACT: Conjugated,linoleic acid (CLA) is a col- lective term,for positional,and,geometric,isomers,of linoleic acid. Dietary CLA has been,shown,to improve feed efficiency, decrease body fat, and increase lean tissue in laboratory,animals.,We hypothesized,that CLA would,improve,performance,and carcass,composi- tion and,would,be deposited,in pork,tissues. Diets of 40 crossbred,pigs were,supplemented,with CLA to de- termine,its effects on performance,and carcass composi- tion. Eight replications,of five littermate,barrows,with an initial average,weight,of 26.3 kg

R. L. Thiel-cooper; F. C. Parrish; J. C. Sparks; B. R. Wiegand; R. C. Ewan


Side chain dependence of intensity and wavenumber position of amide I' in IR and visible Raman spectra of XA and AX dipeptides.  


A series of AX and XA dipeptides in D2O have been investigated by FTIR, isotropic, and anisotropic Raman spectroscopy at acidic, neutral, and alkaline pD, to probe the influence of amino acid side chains on the amide I' band. We obtained a set of spectral parameters for each peptide, including intensities, wavenumbers, half-widths, and dipole moments, and found that these amide I' parameters are indeed dependent on the side chain. Side chains with similar characteristic properties were found to have similar effects on the amide I'. For example, dipeptides with aliphatic side chains were found to exhibit a downshift of the amide I' wavenumber, while those containing polar side chains experienced an increase in wavenumber. The N-terminal charge causes a substantial upshift of amide I', whereas the C-terminal charge causes a moderate decrease of the transition dipole moment. Density functional theory (DFT) calculations on the investigated dipeptides in vacuo yielded different correlations between theoretically and experimentally obtained wavenumbers for aliphatic/aromatic and polar/charged side chains, respectively. This might be indicative of a role of the hydration shell in transferring side chain-backbone interactions. For Raman bands, we found a correlation between amide I' depolarization ratio and wavenumber which reflects that some side chains (valine, histidine) have a significant influence on the Raman tensor. Altogether, the obtained data are of utmost importance for utilizing amide I as a tool for secondary structure analysis of polypeptides and proteins and providing an experimental basis for theoretical modeling of this important backbone mode. This is demonstrated by a rather accurate modeling for the amide I' band profiles of the IR, isotropic Raman, and anisotropic Raman spectra of the beta-amyloid fragment Abeta(1-82). PMID:16851958

Measey, Thomas; Hagarman, Andrew; Eker, Fatma; Griebenow, Kai; Schweitzer-Stenner, Reinhard



Uveitis induction in the rabbit by muramyl dipeptides.  

PubMed Central

Intraocular inflammation (uveitis) was produced in rabbits by intravenous or subcutaneous treatment with N-acetylmuramyl-L-alanyl-D-isoglutamine and several of its synthetic analogs at doses of greater than or equal to 0.2 mg/kg in saline. A dose-dependent increase in permeability of the ocular blood-aqueous barrier as measured by leakage of protein or fluoresceinated dextran from the serum into the eye was observed from 2 to 14 h after glycopeptide treatment. Peak response occurred at approximately 3 h postdose. The lowest dose found to produce maximal vascular leakage for the most active glycopeptide analogs was 1 mg/kg. The adjuvant-inactive L-L stereoisomer of N-acetylmuramyl-L-alanyl-D-isoglutamine was inactive, even at doses as high as 10 mg/kg. Analogs of N-acetylmuramyl-L-alanyl-D-isoglutamine which were homologous in the lactyl side chain were found to cause less uveitis. Chronic biweekly intravenous treatment of rabbits for 1 month with either N-acetyl-L-alpha-aminobutyryl-D-isoglutamine or its lipophilic 6-O-stearoyl derivative at 1 mg/kg, but not with murabutide, resulted in leukocytic inflammatory lesions unique to the uveal tract of the eye. The uveitis was potentially reversible and occurred with decreased severity as long as 2 months after cessation of chronic treatment. Vascular leakage but not cellular infiltrate in the choroid could be modulated by pharmacologic means. Pyrogenicity but not adjuvanticity correlated with ability of glycopeptides to induce vascular leakage. Several adjuvant-active muramyl dipeptide analogs with minimal ability to cause acute vascular leakage or chronic inflammation in the rabbit eye have been identified. Images

Waters, R V; Terrell, T G; Jones, G H



Properties of polylactic acid composites reinforced with oil palm biomass microcrystalline cellulose.  


In this work, polylactic acid (PLA) composites filled with microcrystalline cellulose (MCC) from oil palm biomass were successfully prepared through solution casting. Fourier transform infrared (FT-IR) spectroscopy indicates that there are no significant changes in the peak positions, suggesting that incorporation of MCC in PLA did not result in any significant change in chemical structure of PLA. Thermogravimetric analysis was conducted on the samples. The T50 decomposition temperature improved with addition of MCC, showing increase in thermal stability of the composites. The synthesized composites were characterized in terms of tensile properties. The Young's modulus increased by about 30%, while the tensile strength and elongation at break for composites decreased with addition of MCC. Scanning electron microscopy (SEM) of the composites fractured surface shows that the MCC remained as aggregates of crystalline cellulose. Atomic force microscopy (AFM) topographic image of the composite surfaces show clustering of MCC with uneven distribution. PMID:23987327

Haafiz, M K Mohamad; Hassan, Azman; Zakaria, Zainoha; Inuwa, I M; Islam, M S; Jawaid, M



The composition of coffee oil and its component fatty acids  

Microsoft Academic Search

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

N. A. Khan; J. B. Brown



Radiation Resistance and Deoxyribonucleic Acid Base Composition of Micrococcus radiodurans  

Microsoft Academic Search

Micrococcus radiodurans is a red-pigmented, non-sporing bacterium which is extremely resistant to both ionizing1 and ultra-violet radiations2. The mechanisms of resistance are not known. In 1962 Kaplan and Zavarine3 examined the relationship between the base composition of DNA in eight species of bacteria and their resistance to X-radiation. On plotting the X-ray dose which reduced the surviving bacteria to 10

B. E. B. Moseley; ARNOLD H. SCHEIN



Deoxyribonucleic acid base composition and genome size of Prochloron  

Microsoft Academic Search

The DNA base composition of the photosynthetic prokaryote Prochloron was determined (on samples collected from the natural environment) to be 40.8 mol% GC. The sharp differential melting curve indicated the absence of significant quantities of contaminating DNA from other organisms. The genome size, estimated from the renaturation kinetics of thermally denatured DNA, was 3.59×109 daltons mol. wt, similar to that

Michael Herdman



Composition of mares' colostrum and milk. Protein content, amino acid composition and contents of macro and micro-elements  

Microsoft Academic Search

Changes in the protein content, protein fractions and amino acid composition of mare's colostrum and milk, and the biological value of milk protein during the first 45 days of lactation were studied. Milk samples (averaging 300–800 cm3) from 29 lactating mares were collected daily at the beginning of lactation and weekly from the 5th to 45th days post-partum. Colostrum samples

Zs. Csapó-Kiss; J. Stefler; T. G. Martin; S. Makray; J. Csapó



Fatty acid composition and squalene content of the marine microalga Schizochytrium mangrovei.  


Certain species of thraustochytrids are being explored as potential producer of polyunsaturated fatty acids for nutritional enrichment of food products and use as feed additives in aquaculture. The fatty acid composition and squalene content were determined in the thraustochytrid, Schizochytrium mangrovei that was newly isolated from decaying Kandelia candel leaves in Hong Kong mangrove habitat. The major fatty acid constituents identified in all three S. mangrovei strains were tetradeanoic acid (C14:0), hexadecanoic acid (C16:0), docosapentaenoic acid (C22:5 n-6, DPA) and docosahexaenoic acid (C22:6 n-3, DHA). DHA was the most predominant polyunsaturated fatty acid, and the percentage of DHA (of total fatty acids) in all these strains varied from 32.29 to 39.14%. Only slight changes were observed in fatty acid composition of the S. mangrovei strains harvested at their early (day 3) and late stationary (day 5) phases. In contrast, the cellular squalene content was affected significantly by the culture time; the largest decrease of squalene content from 0.162 mg/g to 0.035 mg/g was found in S. mangrovei FB1 as the culture aged. PMID:14995120

Jiang, Yue; Fan, King-Wai; Wong, Raymond Tsz-Yeung; Chen, Feng



A Novel ?-Peptidyl Aminopeptidase (BapA) from Strain 3-2W4 Cleaves Peptide Bonds of Synthetic ?-Tri- and ?-Dipeptides  

PubMed Central

A novel bacterial strain that was capable of growing on the ?-tripeptide H-?hVal-?hAla-?hLeu-OH as the sole carbon and nitrogen source was isolated from an enrichment culture. On the basis of physiological characterization, partial 16S rRNA sequencing, and fatty acid analysis, strain 3-2W4 was identified as a member of the family Sphingomonadaceae. Growth on the ?-tripeptide and the ?-dipeptide H-?hAla-?hLeu-OH was observed, and emerging metabolites were characterized. Small amounts of a persisting metabolite, the N-acetylated ?-dipeptide, were identified in both media. According to dissolved organic carbon measurements, 74 to 80% of the available carbon was dissimilated. The ?-peptide-degrading enzyme was purified from the crude cell extract of cells from strain 3-2W4 grown on complex medium. The enzyme was composed of two subunits, and the N-terminal sequences of both were determined. With this information, it was possible to identify the complete nucleotide sequence and to deduce the primary structure of the gene bapA. The gene encoded a ?-peptidyl aminopeptidase (BapA) of 402 amino acids that was synthesized as preprotein with a signal sequence of 29 amino acids. The enzyme was cleaved into two subunits (residues 30 to 278 and 279 to 402). It belonged to the N-terminal nucleophile (Ntn) hydrolase superfamily.

Geueke, Birgit; Namoto, Kenji; Seebach, Dieter; Kohler, Hans-Peter E.



Fatty acid composition in seed oils of some onagraceae  

Microsoft Academic Search

The seeds ofOenothera picensis, O. indecora, Ludwigia longifolia andL. peruviana (Onagraceae) contained 18.3, 16.4, 13.9 and 10.1% oil, respectively. Chromatographic analyses showed high levels of linoleic\\u000a acid (>71.5%) in the seed oils.

J. A. Zygadlo; R. E. Morero; R. E. Abburra; C. A. Guzman



Fatty acid composition of six freshwater wild cyanobacterial species.  


Hydroxy, n-saturated, branched, dioic, and unsaturated fatty acids in six freshwater wild cyanobacteria (Chroococcus minutus, Lyngbya ceylanica, Merismopedia glauca, Nodularia sphaerocarpa, Nostoc linckia, and Synechococcus aeruginosus) collected from different lakes and springs of Israel have been identified by gas chromatography-mass spectrometry (GC-MS). PMID:12744080

Rezanka, T; Dor, I; Prell, A; Dembitsky, V M



Genome-wide association study for fatty acid composition in Japanese Black cattle.  


Fatty acid composition is one of the important traits in beef. The aim of this study was to identify candidate genomic regions for fatty acid composition by genome-wide association study with 50?K single nucleotide polymorphism (SNP) array in Japanese Black cattle. A total of 461 individuals and 40?657 SNPs were used in this study. We applied genome-wide rapid association using mixed model and regression (GRAMMAR) and genomic control approaches to estimate the associations between genotypes and fatty acid composition. In addition, two SNPs in fatty acid synthase (FASN) (T1952A) and stearoyl-CoA desaturase (SCD) (V293A) genes were also genotyped. Association analysis revealed that 30 significant SNPs for several fatty acids (C14:0, C14:1, C16:1 and C18:1) were located in the BTA19?FASN gene located within this region but the FASN mutation had no significant effect on any traits. We also detected one significant SNP for C18:1 on BTA23 and two SNPs for C16:0 on BTA25. The region around 17?Mb on BTA26 harbored two significant SNPs for C14:1 and SNP in SCD in this region showed the strongest association with C14:1. This study demonstrated novel candidate regions in BTA19, 23 and 25 for fatty acid composition. PMID:23607548

Ishii, Atsushi; Yamaji, Keita; Uemoto, Yoshinobu; Sasago, Nanae; Kobayashi, Eiji; Kobayashi, Naohiko; Matsuhashi, Tamako; Maruyama, Shin; Matsumoto, Hirokazu; Sasazaki, Shinji; Mannen, Hideyuki



Comparison of microleakage on one composite etched with phosphoric acid or a combination of phosphoric and hydrofluoric acids and bonded with several different systems  

Microsoft Academic Search

Statement of problem. There are no data available on whether or to what extent hydrofluoric acid affects the marginal integrity of dentin-bonded composite restorations when it is used instead of phosphoric acid in the total-etch technique. Purpose. This in vitro study examined the etching effects of phosphoric acid versus a combination of phosphoric and hydrofluoric acid by evaluation of microleakage

Susanne Szep; Nicole Langner; Silja Bayer; Diana Börnichen; Christoph Schulz; Thomas Gerhardt; Anette Schriever; Joachim Becker; Detlef Heidemann



Fatty acid composition, eicosanoid production and permeability in skin tissues of rainbow trout ( Oncorhynchus mykiss) fed a control or an essential fatty acid deficient diet  

Microsoft Academic Search

Rainbow trout (Oncorhynchus mykiss) were fed either a control diet containing fish oil or an essential fatty acid (EFA) deficient diet containing only hydrogenated coconut oil and palmitic acid as lipid source (93.4% saturated fatty acids) for 14 weeks and the fatty acid compositions of individual phospholipid classes from skin and opercular membrane (OM) determined. The permeability of skin and

C. Ghioni; J. G. Bell; M. V. Bell; J. R. Sargent



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

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)

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



Fatty acid composition, extraction, fractionation, and stabilization of bullfrog ( Rana catesbeiana ) oil  

Microsoft Academic Search

The oil extracted from the fat-storage organ (fat body) of the bullfrog (Rana catesbeiana) was characterized for its fatty acid composition. The main fatty acids were palmitic (18.1%), stearic (4.1%), myristic (2.7%),\\u000a oleic (31.7%), and linoleic (12.9%) acids. Long-chain polyunsaturated fatty acids were also present in significant amounts,\\u000a i.e., eicosapentaenoic (1.5%) and docosahexaenoic (4.7%), and were probably derived from the

Eduardo Méndez; Julio Sanhueza; Susana Nieto; Hernán Speisky; Alfonso Valenzuela



Frying stability of soybean and canola oils with modified fatty acid compositions  

Microsoft Academic Search

Pilot plant-processed samples of soybean and canola (lowerucic acid rapeseed) oil with fatty acid compositions modified by\\u000a mutation breeding and\\/or hydrogenation were evaluated for frying stability. Linolenic acid contents were 6.2% for standard\\u000a soybean oil, 3.7% for low-linolenic soybean oil and 0.4% for the hydrogenated low-linolenic soybean oil. The linolenic acid\\u000a contents were 10.1% for standard canola oil, 1.7% for

K. Warner; T. L. Mounts



Poly(2,5-benzoxazole)\\/carbon nanotube composites via in situ polymerization of 3-amino-4-hydroxybenzoic acid hydrochloride in a mild poly(phosphoric acid)  

Microsoft Academic Search

Poly(2,5-benzoxzole) (ABPBO)\\/carbon nanotube (CNT) composites were prepared via in situ polycondensation of “protonated” AB monomer, 3-amino-4-hydroxybenzoic acid hydrochloride, in a mildly acidic poly(phosphoric acid) medium. In situ generated hydrochloric acid during the dehydrochlorination process provided additional acidity to the reaction medium. The enhanced acidity was advantageous for both the purification and dispersion of CNTs. Specifically, it was evident for the

Soo-Mi Eo; Se-Jin Oh; Loon-Seng Tan; Jong-Beom Baek



Method for Detection of Thiol-containing Amino Acids Using Gold-Polystyrene Composites  

PubMed Central

This paper reports the preparation of PS-PEI-Au composite colloids via the utilization of a facile method involving poly(ethylenimine) (PEI). The PEI used in the reaction scheme served the role of a linker between Au and PS and additionally as a reducing agent in the conversion of Au ions to Au NPs. The PS-PEI-Au colloids thus prepared were characterized by scanning electron microscopy, UV-Vis and IR spectroscopy and cyclic voltammetry. The PS-PEI-Au composites were further used for the detection of the thiol-containing amino acids, cysteine and homocysteine, via Attenuated Total Reflection (ATR) spectroscopy. Experimental results revealed interfacial binding of the amino acids to the composites, and correlated with successive additions of the respective amino acids.

Murray, Davoy



Influence of a peracetic acid-based immersion on indirect composite resin.  


The aim of this study was to evaluate the influence of immersion in a 0.2% peracetic acid-based disinfectant on the three-point flexural strength, water sorption and water solubility of an indirect composite resin. Specimens were produced according to ISO 4049:2000 specifications and were divided in two groups: Control group, with no disinfection and Disinfected group, with three 10 min immersions in the peracetic acid intercalated with 10 min immersions in sterile distilled water. All evaluations were conducted in compliance with ISO specifications. Three-point flexural strength, water sorption and solubility of indirect composite resin before and after immersion showed no statistical significant differences (p > 0.05) and met ISO standard requirements. Immersion in peracetic acid solution showed no influence in indirect composite resin tested properties. PMID:21780726

Samuel, Susana Maria Werner; Fracaro, Gisele Baggio; Collares, Fabrício Mezzomo; Leitune, Vicente Castelo Branco; Campregher, Ulisses Bastos



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

Microsoft Academic Search

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

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



Opportunities of deoxyribonucleic acid complexes composites for nonlinear optical applications  

NASA Astrophysics Data System (ADS)

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.

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



Phenolic acid induced growth of gold nanoshells precursor composites and their application in antioxidant capacity assay.  


In the present work, the gold nanoshells (GNSs) precursor composites were preadsorbed onto the surface of ITO substrates. With the treatment of modified electrodes immersed in the gold nanoparticles (GNPs) growth solution containing different phenolic acids, the GNSs precursor composites were enlarged to varying degrees. Phenolic acids with one or more phenolic hydroxyl groups served as reductants for the growth of GNPs. The enlargement conditions varied with the different reducing capacity of phenolic acids, exhibiting specific morphologies differ from the complete GNSs. Consequently, the UV-vis-NIR spectra and cyclic voltammetry curves for the phenolic acid-treated ITO electrode were gradually changed. Results showed that the higher reducing capacity for phenolic acid to reduce AuCl(4)(-) to Au(0) resulted in the intensified localized surface plasmon resonance features and reduced cathodic currents. The spectral wavelength peaks red shifted hundreds of nanometers across the visible region. Moreover, the antioxidant capacity of phenolic acids correlates well with their reducing activity, both of which reflect their tendency to donate electrons. Thus, the optical and electrochemical results could be used to evaluate the antioxidant capacity of phenolic acids by utilizing GNSs precursor composites as nanoprobes. The method is simple, rapid and could be used in visual analysis to a certain extent. PMID:20863682

Ma, Xiaoyuan; Qian, Weiping



Warning about Fatty Acid Compositions in Some Iranian Mayonnaise Salad Dressings  

PubMed Central

Objectives: The beneficial or detrimental effects of dietary fats on health and well-being largely depend on their fatty acid composition. The contribution of high intake of trans fatty acids (TFAs) and saturated fatty acids (SFAs) to the risk of coronary heart disease is well documented. In this study, the fatty acid composition of different samples of mayonnaise salad dressing produced in Iran wasanalyzed. Methods: Three most consumed samples from four different brands of Iranian mayonnaises were purchased. Total lipids were extracted with Folch technique. All samples were transformed into methyl ester and analysis of fatty acid methyl esters were performed by gas chromatography (GC) with 60 meters capillary columns and flame ionization detectors. Results: TFAs ranged from 0.6% to 3.5%,with linolelaidic acid (C18:2 9t, 12t) being the most common form of fatty acid in Iranian mayonnaises, which had high amounts of SFAs (from18.1% to 24.9%) and unsaturated fatty acids (68.4%to 74.4%). Conclusions: The most common type of fatty acids in Iranian tested mayonnaises were unsaturated ones followed by SFAs. Significant variations were found among the contents of TFAs in these products, which is related to their procedure. Improvement of the fat quality in this highly consumed food product might have a long-term impact on prevention of chronic diseases.

Nazari, Bahar; Asgary, Sedigheh; Sarrafzadegan, Nizal



Hormone-sensitive lipase deficiency disturbs the fatty acid composition of mouse testis.  


Hormone-sensitive lipase (HSL) is a key enzyme in the mobilization of fatty acids from intracellular stores. In mice, HSL deficiency results in male sterility caused by a major defect in spermatogenesis. The testes contain high concentrations of PUFA and specific PUFA are essential for spermatogenesis. We investigated the fatty acid composition and the mRNA levels of key enzymes involved in fatty acid metabolism in testis of HSL-knockout mice. HSL deficiency altered fatty acid composition in the testis but not in plasma. The most important changes were decreases in the essential n-6 PUFA LNA and the n-3 PUFA ALA, and an increase in the corresponding synthesis intermediates C22:4n-6 and C22:5n-3 without changes in DPAn-6 or DHA acids. Mead acid, which has been associated with an essential fatty acid deficit leading to male infertility, was increased in the testis from HSL-knockout mice. Moreover, the expression of SCD-1, FADS1, and FADS2 was increased while expression of ELOVL2, an essential enzyme for the formation of very-long PUFA in testis, was decreased. Given the indispensability of these fatty acids for spermatogenesis, the changes in fatty acid metabolism observed in testes from HSL-knockout male mice may underlie the infertility of these animals. PMID:23369366

Casado, M E; Pastor, O; Mariscal, P; Canfrán-Duque, A; Martínez-Botas, J; Kraemer, F B; Lasunción, M A; Martín-Hidalgo, A; Busto, R



Characteristics of fatty acid composition of lipids in higher plant vacuolar membranes.  


The fatty acid composition of vacuolar membrane lipids from plant storage tissues and their genesis have been studied. A high content of unsaturated fatty acids (up to 77%) was observed in lipids of these membranes. Linoleic acid prevailed in vacuolar lipids of carrot and red beet (54.2 and 44.2%, respectively). Linolenic acid prevailed in vacuolar lipids of garden radish and turnip (39.7 and 33.9%, respectively). Regarding saturated fatty acids, vacuolar lipids of garden radish, carrot, and red beet contained predominantly palmitic acid (up to 20-24%). Unsaturated fatty acids, petroselinic (C18: 1omega12), cis-vaccenic (C18: 1omega7), hexatrien-7,-10,-13-oic (C16:3omega3) and others, were observed in vacuolar lipids of roots. These acids are usually synthesized in chloroplasts, and their presence in vacuolar lipids can be associated either with the transport of metabolites to the vacuole, or with endocytosis during vacuolar formation in the plant cell. The specific features of fatty acid composition of tonoplast lipids apparently are closely related to the tonoplast unique fluidity and mobility required for running osmotic processes in the cell and for forming transport protein assemblies. PMID:10987391

Makarenko, S P; Konenkina, T A; Salyaev, R K



Genetic variation of FASN is associated with fatty acid composition of Hanwoo.  


The objective of this study was to identify genetic variants in the bovine fatty acid synthase (FASN) gene and to evaluate associations with fatty acid composition from longissimus lumborum muscle using 90 purebred Hanwoo steers. Sequence alignments observed 6 genetic variants located in exons 20, 24, 32, 34, and 39, and PCR-RFLP analysis confirmed these variations. Genotypes of the g.15532A>C locus were significantly associated with Linolenic acid (C18:3), and genotypes of the g.17924G>A locus were significantly associated with Palmitic (C16:0), Palmitoleic (C16:1), Oleic (C18:1), saturated fatty acids, and unsaturated fatty acids. The analysis revealed that SFA and UFA showed significant correlations with fatty acid composition (Myristic (C14:0), Palmitic (C16:0), Stearic (C18:0), Oleic (C18:1), and Eicosenoic (C20:1) acids). Oleic acid (C18:1) was negatively correlated with Myristic (C14:0), Palmitic (C16:0), and Palmitoleic (C16:1) acids (P<0.001). PMID:23403305

Yeon, S H; Lee, S H; Choi, B H; Lee, H J; Jang, G W; Lee, K T; Kim, K H; Lee, J H; Chung, H Y



Lipid and fatty acid composition and energy partitioning during embryo development in the shrimp Macrobrachium borellii  

Microsoft Academic Search

Energy partitioning, composition of lipids and fatty acids, and their utilization by embryos were determined in the lecithotrophic\\u000a shrimp Macrobrachium borellii during seven development stages. The biochemical composition at stage I is represented by lipids, proteins, and carbohydrates,\\u000a with 29.3, 28.7, and 0.2% dry weight, respectively. The former two were identified as the major energy-providing components,\\u000a contributing 131 and 60

Horacio Heras; M. R. Gonzalez-Baró; Ricardo J. Pollero



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

Microsoft Academic Search

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

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



Change of ginsenoside composition in red ginseng processed with citric acid  

Microsoft Academic Search

The purpose of this research was to investigate the composition of ginsenosides and to identify the chemical structures of\\u000a ginsenosides generated from red ginseng by citric acid pre-treatment (RGC). The amount and the composition of ginsenosides\\u000a in red ginseng (RG) and RGC were determined by high performance liquid chromatography (HPLC) analysis. The content of Rg3, a well-known bioactive ginsenoside in

Jung-Hyun Yi; Min-Young Kim; Young-Chan Kim; Woo-Sik Jeong; Dong-Won Bae; Jong-Moon Hur; Mira Jun



Water absorption and enzymatic degradation of poly(lactic acid)\\/rice starch composites  

Microsoft Academic Search

Poly(lactic acid) (PLA) composites consisting of PLA, rice starch (RS) (0–50wt%) and epoxidised natural rubber (ENR50) were compounded by a twin-screw extruder and compression moulded into dumbbell specimens. Tensile tests were performed to characterize the mechanical properties of the PLA\\/RS composites. Morphological studies were done on the tensile fractured surface of the specimens by using scanning electron microscopy (SEM). Twenty

G. H. Yew; A. M. Mohd Yusof; Z. A. Mohd Ishak



Evaluation of Poly(lactic acid) and Sugar Beet Pulp Green Composites  

Microsoft Academic Search

Poly(lactic acid) (PLA) and sugar beet pulp (SBP) were compounded by twin-screw extrusion and injection molded into composite\\u000a forms. Specific mechanical energy decreased with the addition of SBP during processing. PLA–SBP composites retained more tensile\\u000a strength than expected based on the Nicolais–Narkis model especially at high levels of SBP suggesting adhesion between SBP\\u000a and PLA. The thermal characteristics of PLA

Victoria L. Finkenstadt; LinShu Liu; J. L. Willett



Effects of Different Types of Dietary Lipids on Growth and Fatty Acid Composition of Largemouth Bass  

Microsoft Academic Search

The effects of feeding diets supplemented with oils of varying sources and fatty acid compositions on growth, survival, and biochemical composition of juvenile largemouth bass Micropterus salmoides were evaluated under controlled conditions in aquaria for 12 weeks. Feed-trained juvenile largemouth bass (15.7 ± 0.6 g) were stocked into eighteen 114-L glass aquaria at 25 fish\\/tank and were fed one of

James H. Tidwell; Shawn Coyle; Leigh Anne Bright



Amino acid composition, including key derivatives of eccrine sweat: potential biomarkers of certain atopic skin conditions.  


The free amino acid (AA) composition of eccrine sweat is different from other biological fluids, for reasons which are not properly understood. We undertook the detailed analysis of the AA composition of freshly isolated pure human eccrine sweat, including some of the key derivatives of AA metabolism, to better understand the key biological mechanisms governing its composition. Eccrine sweat was collected from the axillae of 12 healthy subjects immediately upon formation. Free AA analysis was performed using an automatic AA analyser after ninhydrin derivatization. Pyrrolidine-5-carboxylic acid (PCA) and urocanic acid (UCA) levels were determined using GC/MS. The free AA composition of sweat was dominated by the presence of serine accounting for just over one-fifth of the total free AA composition. Glycine was the next most abundant followed by PCA, alanine, citrulline and threonine, respectively. The data obtained indicate that the AA content of sweat bears a remarkable similarity to the AA composition of the epidermal protein profilaggrin. This protein is the key source of free AAs and their derivatives that form a major part of the natural moisturizing factor (NMF) within the stratum corneum (SC) and plays a major role in maintaining the barrier integrity of human skin. As perturbations in the production of NMF can lead to abnormal barrier function and can arise as a consequence of filaggrin genotype, we propose the quantification of AAs in sweat may serve as a non-invasive diagnostic biomarker for certain atopic skin conditions, that is, atopic dermatitis (AD). PMID:23075272

Mark, Harker; Harding, Clive R



Screening of soy protein-derived hypotriglyceridemic di-peptides in vitro and in vivo  

PubMed Central

Background Soy protein and soy peptides have attracted considerable attention because of their potentially beneficial biological properties, including antihypertensive, anticarcinogenic, and hypolipidemic effects. Although soy protein isolate contains several bioactive peptides that have distinct physiological activities in lipid metabolism, it is not clear which peptide sequences are responsible for the triglyceride (TG)-lowering effects. In the present study, we investigated the effects of soy protein-derived peptides on lipid metabolism, especially TG metabolism, in HepG2 cells and obese Otsuka Long-Evans Tokushima fatty (OLETF) rats. Results In the first experiment, we found that soy crude peptide (SCP)-LD3, which was prepared by hydrolyze of soy protein isolate with endo-type protease, showed hypolipidemic effects in HepG2 cells and OLETF rats. In the second experiment, we found that hydrophilic fraction, separated from SCP-LD3 with hydrophobic synthetic absorbent, revealed lipid-lowering effects in HepG2 cells and OLETF rats. In the third experiment, we found that Fraction-C (Frc-C) peptides, fractionated from hydrophilic peptides by gel permeation chromatography-high performance liquid chromatography, significantly reduced TG synthesis and apolipoprotein B (apoB) secretion in HepG2 cells. In the fourth experiment, we found that the fraction with 0.1% trifluoroacetic acid, isolated from Frc-C peptides by octadecylsilyl column chromatography, showed hypolipidemic effects in HepG2 cells. In the final experiment, we found that 3 di-peptides, Lys-Ala, Val-Lys, and Ser-Tyr, reduced TG synthesis, and Ser-Tyr additionally reduced apoB secretion in HepG2 cells. Conclusion Novel active peptides with TG-lowering effects from soy protein have been isolated.



Shape control of cellulose nanocrystals via compositional acid hydrolysis.  


The current medical technology has constantly demanded novel and advanced materials exhibiting the unique physicochemical properties but, at the same time, possessing the intrinsic biocompatibility. Natural biomolecules based on materials such as peptide- (or protein-) or DNA/RNA derivatives have been formerly considered. To date, a carbohydrate-derived molecule has been a highlight as a substitute with the prior biomaterials, which suffer from their sequence-dependent immuno-cytoxicity. Of most, cellulose based materials have had a profound interest due to the great mechanical and optochemical properties as well as its immune-friendliness. However, it has been further manipulated in order to get distinctive structures at the desired shape and scale. Here, we report the versatile and synthetic technique to prepare spherical or rod-like cellulose nanocrystals (CNC). Under the varying concentrations of strong sulfuric acids (H2SO4) and hydrochloric acids (HCI), spherical or rod-typed CNCs were selectively manufactured via acid hydrolysis of microcrystalline celluloses (MCC) in massive bundles. At the sequential addition of H2SO4 and HCI in 1 to 2.5 molar ratios, most interestingly, the spherical CNC alone was observed with the average size of 50 nm in narrow distribution. All of CNCs had the larger surface area with mesoporosity. In addition, it was confirmed by the crystallographic measurement that it was very similar to the maternal structure originating from the bundle celluloses. It is much anticipated that the porous cellulose nanocrystals may play a principal role as a potential drug carrier for diseased biological compartments. PMID:23909145

Baek, Changyoon; Hanif, Zahid; Cho, Seung-Woo; Kim, Dong-Ik; Um, Soong Ho



Peroxisome proliferator-activated receptor alpha agonist, clofibrate, has profound influence on myocardial fatty acid composition.  


The hypolipidemic fibrates have been identified as agonists of the peroxisome proliferator-activated receptor alpha (PPARalpha), which plays a critical role in the regulation of cardiac fatty acid metabolism. Despite the widespread clinical use of fibrates, their role in myocardial oxidative stress and fatty acid composition is less known. In this study, male Sprague-Dawley rats were treated with either vehicle (olive oil, 1 ml/kg) or clofibrate (300 mg/kgday i.p.) for 1-14 days. Lipid peroxidation in heart homogenate was determined by thiobarbituric acid reactive substance (TBARS) assay. Results show that hearts from clofibrate-treated rats are more susceptible to FeSO(4)-induced TBARS production. The antioxidants including catalase and glutathione-related enzymes were marginally affected. We demonstrated that myocardial fatty acid composition was dramatically altered by clofibrate treatment. In hearts from clofibrate-treated rats, the principal n-6 polyunsaturated fatty acids (PUFAs), linoleic acid (C18:2 n-6) and arachidonic acid (C20:4 n-6), was significantly reduced, while the content of the principal n-3 PUFA, docosahexaenoic acid (C22:6 n-3), was markedly increased. The overall effect was to reduce n-6/n-3 ratio and increase the unsaturation extent of myocardial fatty acids. Functional study showed that hearts from clofibrate-treated rats had an improved recovery of post-ischemic contractile function and reduced ischemia/reperfusion (I/R)-induced infarct size. The data shows that clofibrate has a profound impact on cardiac fatty acid composition, which may contribute to its cardioprotective effect. PMID:16540100

Tian, Qi; Grzemski, Felicity A; Panagiotopoulos, Sianna; Ahokas, Jorma T



A Comparison of Proximate Composition And Fatty Acid Profile of Indus River Fish Species  

Microsoft Academic Search

Eight species of freshwater fish from the Indus River were analyzed for their proximate composition and fatty acid (FA) profile. Differences were observed (P < 0.05) for moisture (59.95–79.45%), ash (0.05–4.95%), crude protein (17–20.09%) and lipid (0.85–18.32%) contents. The changes in FA profiles of fish species were significant (P < 0.05). The monounsaturated (MUFA) fatty acid content (24.55–48.35 g\\/100 g)

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



Effect of sampling fat location and cooking on fatty acid composition of beef steaks  

Microsoft Academic Search

To investigate the impact of sampling fat location and cooking on fatty acid composition of beef steaks, 21 raw steaks from crossbred steers were dissected to obtain outer (OSC) and inner subcutaneous fat (ISC), seam fat, marbling, and lean muscle. Twenty-one cooked steaks were dissected to obtain OSC, ISC, seam fat, surface and inner muscle. Trans-vaccenic acid and c9, t11-CLA

T. Jiang; J. R. Busboom; M. L. Nelson; J. O’Fallon; T. P. Ringkob; D. Joos; K. Piper



Composition of cecal bile acids in ex-germfree mice inoculated with human intestinal bacteria  

Microsoft Academic Search

Germfree (GF) mice were orally inoculated with human fecal suspension or various components of human fecal microbiota. Three\\u000a weeks after the inoculation, cecal bile acid composition of these mice was examined. More than 80% of total bile acids was\\u000a deconjugated in the cecal contents of ex-GF mice associated with human fecal dilutions of 10?2 or 10?6, or anaerobic growth from

Seiko Narushima; Kikuji Iton; Kazuo Kuruma; Kiyohisa Uchida



Effect of composition of sucrose fatty acid esters on formation of palladium nanoparticles in reverse micelles  

Microsoft Academic Search

Palladium (Pd) nanoparticles were prepared in the reverse micellar system containing sucrose fatty acid esters with various\\u000a esterification degrees. The TEM showed that Pd nanoparticles were of spherical and relatively uniform. The size of Pd nanoparticles\\u000a strongly depended upon the composition of sucrose fatty acid esters. The resultant Pd colloid could be preserved for at least\\u000a 2 months without precipitation.

Hidetaka Noritomi; Kenji Kagitani; Yasutaka Muratsubaki; Satoru Kato



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

Microsoft Academic Search

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

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


Serum fatty acid composition as a marker of eating habits in normal and diabetic subjects  

Microsoft Academic Search

It is known that the Japanese people have had healthy eating habits, which may explain their low incidence of non-insulin-dependent diabetes mellitus (NIDDM). In the present study, in order to examine dietary habits such as fish consumption, the serum fatty acids from 190 normal people in their 30s and 50s living in Tokyo were surveyed. Furthermore, the fatty acid composition

Takashi Hasegawa; Mieko Oshima



Amino acid composition and anti-anaemia action of hydrolyzed offal protein from Harengula Zunasi Bleeker  

Microsoft Academic Search

A hydrolyzed offal protein (HOP) from Harengula Zunasi offal was produced according to the poly-enzymatic method. Its amino acid composition and in vivo anti-anaemia action were investigated. Chemical analysis showed that the hydrolyzed offal protein contained 16.0% protein, 4.21% fat, 76.28% moisture and 3.39% ash. Compared with the amino acid profiles recommended by FAO\\/WHO, the protein quality of the hydrolyzed

Deng Shang-gui; Peng Zhi-ying; Chen Fang; Yang Ping; Wu Tie



Relation between fatty acid composition and iodine value of cottonseed oil  

Microsoft Academic Search

Summary  The regularity in the increase in linoleic, and in the decrease in oleic and saturated acids with increase in iodine value\\u000a of cottonseed oils has been shown by obtaining the regression equation for the glyceride of each acid on the iodine value\\u000a by use of the compositional data on 48 samples of oil ranging from 89.8 to 117.0 in iodine

Mack F. Stansbury; Carroll L. Hoffpauir



Fatty acid composition of erythrocyte, platelet, and serum lipids in strict vegans  

Microsoft Academic Search

The fatty acid composition of erythrocytes, platelets, and serum lipids was compared between subjects who had been eating\\u000a a strict uncooked vegan diet (“living food”) for years and omnivore controls. The vegan diet contains equal amounts of fat\\u000a but more monounsaturated and polyunsaturated and less saturated fatty acids than the mixed diet of the control group. In vegans,\\u000a the proportion

Jyrki J. Ågren; Marja-Leena Törmälä; Mikko T. Nenonen; Osmo O. Hänninen



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

NASA Astrophysics Data System (ADS)

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).

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



Age-dependent fatty acid composition of erythrocyte membrane phospholipids in healthy children.  


The fatty-acid composition of red-cell-membrane phospholipids (total phospholipids, phosphatidylcholine, and phosphatidylethanolamine fractions) was determined in 88 apparently healthy children aged 1 to 15 years, 10 cord blood samples, and 6 infants below 1 year of age. The major aim of the study was to determine the normal ranges of fatty-acid proportions, including trans- and odd-numbered fatty acids, for further studies of nutritional and metabolic disorders. The concentrations of most fatty acids of the phospholipids analyzed increased or decreased after birth and assumed adult levels before the second year of life, alpha-linolenic acid (C18:3n - 3) and trans fatty acids, however, continued to increase with age until late childhood. PMID:2080640

Laryea, M; Cieslicki, P; Diekmann, E; Wendel, U



Influence of Fatty Acid Precursors, Including Food Preservatives, on the Growth and Fatty Acid Composition of Listeria monocytogenes at 37 and 10?C ?  

PubMed Central

Listeria monocytogenes is a food-borne pathogen that grows at refrigeration temperatures and increases its content of anteiso-C15:0 fatty acid, which is believed to be a homeoviscous adaptation to ensure membrane fluidity, at these temperatures. As a possible novel approach for control of the growth of the organism, the influences of various fatty acid precursors, including branched-chain amino acids and branched- and straight-chain carboxylic acids, some of which are also well-established food preservatives, on the growth and fatty acid composition of the organism at 37°C and 10°C were studied in order to investigate whether the organism could be made to synthesize fatty acids that would result in impaired growth at low temperatures. The results indicate that the fatty acid composition of L. monocytogenes could be modulated by the feeding of branched-chain amino acid, C4, C5, and C6 branched-chain carboxylic acid, and C3 and C4 straight-chain carboxylic acid fatty acid precursors, but the growth-inhibitory effects of several preservatives were independent of effects on fatty acid composition, which were minor in the case of preservatives metabolized via acetyl coenzyme A. The ability of a precursor to modify fatty acid composition was probably a reflection of the substrate specificities of the first enzyme, FabH, in the condensation of primers of fatty acid biosynthesis with malonyl acyl carrier protein.

Julotok, Mudcharee; Singh, Atul K.; Gatto, Craig; Wilkinson, Brian J.



Controlled release of gentamicin from calcium phosphate—poly(lactic acid- co-glycolic acid) composite bone cement  

Microsoft Academic Search

Modification of a self setting bone cement with biodegradable microspheres to achieve controlled local release of antibiotics without compromising mechanical properties was investigated. Different biodegradable microsphere batches were prepared from poly(lactic-co-glycolic acid) (PLGA) using a spray-drying technique to encapsulate gentamicin crobefate varying PLGA composition and drug loading. Microsphere properties such as surface morphology, particle size and antibiotic drug release profiles

Julia Schnieders; Uwe Gbureck; Roger Thull; Thomas Kissel



Effect of dietary fatty acid composition on the biosynthesis of unsaturated fatty acids in rat liver microsomes  

Microsoft Academic Search

A study was made of the influence of semisynthetic diets of low and high unsaturation on the fatty acid composition and desaturation-chain\\u000a elongation enzymatic activity of the liver microsomal fractions of male Sprague-Dawley rats of different ages. Groups of rats\\u000a were fed 5 or 20% coconut oil (CO), or a 5 or 20% mixture of corn and menhaden oils (3?7)

Norimasa Kurata; O. S. Privett



[Composition of fat acids in three Mexican populations of Artemia franciscana from epicontinental waters].  


In this paper is presented the percentage of fatty acids composition of three Artemia franciscana Mexican populations of epicontinentals waters; two are from natural environments (Coahuila and San Luis Potosf) and one (Texcoco) is a culture fed with Spirulina. Determination of fatty acids composition in each population, was performed by extraction of total lipid by the soxhlet method and the fatty acids methyl esters were determined by gas chromatography. The results show that Artemia of Texcoco contains the six fatty acids recommended for the culture of fish and crustaceans (16:0; 16:1; 18:1; 18:2w6; 18:3w3 and 20:5w3); Artemia from San Luis Potosi showed the poorest content in these acids and Artemia from Coahuila, although it showed a wide profile, it lacks the linolenic acid. When comparing results among the three populations with ecological data that have been published, it can be pointed out that the environment is decisive for this crustacean; Artemia from Texcoco fed with Spirulina showed the largest variety of fatty acids; the other two populations are wild, and lives in different habitats, Artemia of Coahuila is found in waters that are rich in sulfates and Artemia of San Luis Potosf lives in evaporation saltern ponds, built with stone blocks and therefore with scarce phytoplankton growth. Both Artemia populations showed deficiencies in essential fatty acids, mainly the last one. PMID:17357427

Malpica Sánchez, Aída; Castro Barrera, Thalía; Sandoval Trujillo, Horacio; Castro Mejía, Jorge; De Lara Andrade, Ramón; Castro Mejía, Germán



Amino acid composition of the protein in pre-emergence nests of a paper wasp, Polistes chinensis (Hymenoptera, Vespidae)  

Microsoft Academic Search

Summary. Amino acid composition of protein in oral secretion, which is widely used for construction and maintenance of social wasp nests, was analyzed in pre-emergence nests of Polistes chinensis. More than 20 amino acids were detected from field and laboratory nests, among which glycine, serine, alanine, valine and proline were major amino acids in all samples analyzed. The amino acid

K. Kudô; H. Yamamoto; Sô Yamane



Medium Evaluation and Plastic Composite Support Ingredient Selection for Biofilm Formation and Succinic Acid Production by Actinobacillus succinogenes  

Microsoft Academic Search

Succinic acid production medium for Actinobacillus succinogenes was simplified. Vitamins and fatty acids were removed from the medium and industrial quality yeast extract was substituted to yield revised succinic acid medium. Customized plastic composite support (PCS) blends were screened for biofilm and succinic acid production. Twenty different PCS blends with and without mineral salt additions were evaluated in twenty simulated

Susan E. Urbance; Anthony L. Pometto III; Alan A. DiSpirito; Ali Demirci



Isolation of Arabidopsis mutants with altered seed fatty acid composition  

SciTech Connect

By direct screening of Arabidopsis seed fatty acid methyl esters, we have isolated mutants which are deficient in the elongation of 18:1 to 20:1 and the desaturation of 18:2 to 18:3. Both the elongation and the desaturation mutants, designated MB14 and BL1 respectively, have only 10% of the wild-type levels of 20:1 and 18:3 in their seeds. The intermediate levels of 20:1 and 18:3 in F1 seeds of crosses to the wild type indicate that the level of enzyme is regulating the amount of 20:1 and 18:3 in seeds. Consistent with this observation, the mutations were found to segregate 1:2:1 in F2 seeds. We have found that the 18:2 desaturase mutation is clearly expressed in root phosphatidylcholine.

Lemieux, B.; Browse, J.; Somerville, C. (Dept. of Energy, East Lansing, MI (USA) Washington State Univ., Pullman (USA))



Glycyl-L-Glutamine: A Dipeptide Neurotransmitter Derived from Beta-Endorphin.  

National Technical Information Service (NTIS)

Glycyl-L-glutamine (Gly-L-Gln) is a dipeptide synthesized post-translationally from beta-endorphin. Gly-L-Gln is a major product of beta-endorphin processing in the brainstem, pituitary and several peripheral tissues, but little is known about its physiol...

W. R. Millington



Natural dipeptides as mini-chaperones: molecular mechanism of inhibition of lens ?L-crystallin aggregation.  


The effect of histidine-containing dipeptides-carnosine and N-acetylcarnosine-on preventing and treating of cataracts of various etiologic origins has been demonstrated in many studies in vivo, while the precise molecular mechanism of their action is actually obscure. Cataract has been recently attributed to conformational diseases due to the association of lens structure protein aggregation with cataract pathogenesis. In our study, effect of histidine-containing dipeptides-carnosine, N-acetylcarnosine, and anserine-on the UV induced ?L-crystallin aggregation was studied in vitro. It was first demonstrated that N-acetylcarnosine and anserine (10-40 mM) considerably suppressed UV induced aggregation of ?L-crystallin, while carnosine exerted no effect. Positive correlation between anti-aggregating activity of the compounds used and their hydrophobicity was obtained. It was revealed that N-acetylcarnosine and anserine inhibited the initial stages of the protein photochemical damage. A decrease in the size of protein aggregates was detected in the presence of N-acetylcarnosine and anserine. UV irradiation of ?L-crystallin resulted in a significant increase in the number of protein carbonyl groups, and the dipeptides studied did not affect this process. We suppose that N-acetylcarnosine and anserine inhibit ?L-crystallin aggregation via formation of a protein-dipeptide complex that prevents macromolecular conformational changes and ensuing protein aggregation. PMID:23387882

Dizhevskaya, Antonina K; Muranov, Konstantin O; Boldyrev, Alexander A; Ostrovsky, Mikhail A



Enantiomeric Interactions between Liquid Crystals and Organized Monolayers of Tyrosine-Containing Dipeptides  

PubMed Central

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.

Bai, Yiqun; Abbott, Nicholas L.



Enantiomeric interactions between liquid crystals and organized monolayers of tyrosine-containing dipeptides.  


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

Bai, Yiqun; Abbott, Nicholas L



Dipeptidyl peptidase IV inhibitory and antioxidative properties of milk protein-derived dipeptides and hydrolysates.  


Selected synthetic dipeptides and milk protein hydrolysates were evaluated for their dipeptidyl peptidase IV (DPP-IV) inhibitory properties, and their superoxide (SO) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activities. DPP-IV inhibition was seen with eight out of the twelve dipeptides and 5 of the twelve hydrolysates studied. Trp-Val inhibited DPP-IV, however, inhibition was not observed with the reverse peptide Val-Trp. The most potent hydrolysate inhibitors were generated from casein (CasH2) and lactoferrin (LFH1). Two Trp containing dipeptides, Trp-Val and Val-Trp, and three lactoferrin hydrolysates scavenged DPPH. The dipeptides had higher SO EC(50) values compared to the milk protein hydrolysates (arising from three lactoferrin and one whey protein hydrolysates). Higher molecular mass fractions of the milk protein hydrolysates were associated with the SO scavenging activity. Trp-Val and one lactoferrin hydrolysate (LFH1) were multifunctional displaying both DPP-IV inhibitory and antioxidant (SO and DPPH scavenging) activities. These compounds may have potential as dietary ingredients in the management of type 2 diabetes by virtue of their ability to scavenge reactive oxygen species and to extend the half-life of incretin molecules. PMID:23219487

Nongonierma, Alice B; FitzGerald, Richard J



Romurtide, a synthetic muramyl dipeptide derivative, accelerates peripheral platelet recovery in nonhuman primate chemotherapy model  

Microsoft Academic Search

We investigated the therapeutic effects of romurtide, a synthetic muramyl dipeptide derivative, on experimental thrombocytopenia induced by carboplatin in cynomolgus monkeys. A prolonged thrombocytopenia due to a severe myelosuppression was induced by carboplatin. Romurtide given subcutaneously elevated significantly the peripheral platelet counts during both early initiation and later recovery phase of thrombocytopenia, thereby shortening the time required for recovery to

Kenji Namba; Hironobu Nitanai; Tsuyoshi Otani; Ichiro Azuma



Phenolic acids composition and antioxidant activity of canola extracts in cooked beef, chicken and pork  

Microsoft Academic Search

Crude polyphenol extracts (15 or 100mg gallic acid equivalents (GAE)\\/kg meat) from canola meal reduced the formation of 2-thiobarbituric acid-reactive substances (TBARS) in pre-cooked beef (66–92%), pork (43–75%) and chicken (36–70%). The canola extract contained sinapic (99.7%), ferulic (0.28%) and p-hydroxybenzoic acids (0.07%).The relationship between polyphenol composition and the antioxidant activity of a blend containing of caffeic, cinnamic, p-coumaric, ferulic,

Amandine Brettonnet; Amitha Hewavitarana; Sharon DeJong; Maria Cecilia Lanari



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

Microsoft Academic Search

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

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


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

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.

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



Ingestion rates and dietary lipids affect growth and fatty acid composition of Dendraster excentricus larvae  

Microsoft Academic Search

This study investigated the effect of single and mixed algal diets on growth, fatty acid composition and ingestion rates for Dendraster excentricus larvae. Larvae were assigned to three single algal diet treatments Isochrysis galbana, Dunaliella tertiolecta or Rhodomonas sp. and four mixed algal diet treatments D. tertiolecta and Rhodomonas, I. galbana and D. tertiolecta, I. galbana and Rhodomonas, D. tertiolecta,

Daniela Schiopu; Sophie B. George; John Castell



Fatty Acid Composition and Community Structure of Plankton from the San Lorenzo Channel, Gulf of California  

Microsoft Academic Search

The structure of the plankton community and fatty acid composition of nano-, micro- and zooplankton are described during four seasons of 1994 from the San Lorenzo Channel. During August, the warmest temperature in the surface water was observed and a thermocline developed between 20 and 30m. In the remaining months, a well-mixed layer occurred in the upper 30m. The chlorophyllacontent

B. E. Lavaniegos; D. López-Cortés



Biogeochemistry of the compost bioreactor components of a composite acid mine drainage passive remediation system  

Microsoft Academic Search

The compost bioreactor (“anaerobic cell”) components of three composite passive remediation systems constructed to treat acid mine drainage (AMD) at the former Wheal Jane tin mine, Cornwall, UK were studied over a period of 16 months. While there was some amelioration of the preprocessed AMD in each of the three compost bioreactors, as evidenced by pH increase and decrease in

D. Barrie Johnson; Kevin B. Hallberg



Anodic corrosion of fiber reinforced lead composites for use in large lead-acid batteries  

Microsoft Academic Search

The corrosion resistance of lightweight, high strength lead metal matrix composites under conditions that simulate their use as grid materials in large lead-acid batteries has been studied. Constant potential testing provides an effective means for holding constant the oxidizing power of a metal-electrolyte system. Data are presented on corrosion currents, effect of exposure time on corrosion rates, dependence of the

C. M. Dacres; S. M. Reamer; R. A. Sutula; I. A. Angres



The fatty acid composition of oophagous tadpoles ( Chirixalus eiffingeri) fed conspecific or chicken egg yolk  

Microsoft Academic Search

We compared the lipid content and fatty acid composition of (1) the egg yolk of three anuran species (Chirixalus eiffingeri, Rhacophorus moltrechti and Buergeria robustus) and chicken eggs; and (2) C. eiffingeri tadpoles fed conspecific eggs or chicken egg yolk. Anuran and chicken egg yolk contained more non-polar than polar lipids but the proportions varied among species. Chicken egg yolk

Chen-Huei Huang; Min-Fang Liang; Yeong-Choy Kam



Phospholipid-derived fatty acids as chemotaxonomic markers for phytoplankton: application for inferring phytoplankton composition  

Microsoft Academic Search

Phospholipid-derived fatty acids (PLFA) are widely used as chemotaxonomic markers in microbial ecology. In this paper we explore the use of PLFA as chemotaxonomic markers for phytoplankton species. The PLFA composition was determined for 23 species relevant to estuarine phytoplankton. The taxonomic groups investigated were Chlorophyceae, Trebouxiophyceae, Prasinophyceae, Bacillariophyceae, Dinophyceae, Cryptophyceae, Rhodophyceae, Pavlovophyceae and Prymnesiophyceae. Most of these taxonomic groups

N. A. Dijkman; J. C. Kromkamp



Chemical composition and fatty acid profile of rhea (Rhea americana) meat  

Microsoft Academic Search

SUMMARY. The purpose of this work was to determine the proximate composition and fatty acid profiles of the Gastrocnemius pars interna intramuscular fat (IMF) of rhea (Rhea americana) thighs. The birds were bred in captivity, fed with balanced feed (Nutriavestruz Crescimento - Purina) and kept in a pen with grass ad lib. The birds of both sexes used in the

Pedro Fernando Romanelli; Elizeu Trabuco; Andréia Borges Scriboni; Vergílio Visentainer; Nilson Evelázio de Souza



Fatty acid composition of lipids in wild Cordyceps sinensis from major habitats in China  

Microsoft Academic Search

Wild Cordyceps sinensis (WCS) is considered to be one rare and valuable medicinal fungus for preventing and treating diverse chronic diseases, and its quality and price vary hugely with different producing areas. However, the determination of geographic origin has long been hindered by uncertainties of existing methods. Lately, it has been found that the fatty acid composition in lipids may

Lian-Xian Guo; Xiao-Ming Xu; Chou-Fei Wu; Li Lin; Shi-Chun Zou; Tian-Gang Luan; Jian-Ping Yuan; Jiang-Hai Wang


Proximate composition and fatty acids profile of green and roasted defective coffee beans  

Microsoft Academic Search

Defective coffee beans are responsible for the depreciation of the quality of roasted coffee consumed in Brazil. The extraction of the oil of defective beans for applications in the food and pharmaceutical sectors is being considered as an alternative use for those beans. The objective of this work was to determine the composition of the fatty acid fraction of the

Leandro S. Oliveira; Adriana S. Franca; Juliana C. F. Mendonça; Mario C. Barros-Júnior



Variation in Oil Content and Fatty Acid Composition in the US Castor Bean Germplasm  

Technology Transfer Automated Retrieval System (TEKTRAN)

Castor has potential as a feedstock for biodiesel production. The oil content and fatty acid composition of castor bean seeds are therefore important factors determining the price and quality of castor bean biodiesel. Forty-eight castor bean and two soybean accessions were selected from the US germp...


Biliary lipid, bile acid composition, and dietary correlations in Micmac Indian women  

Microsoft Academic Search

The precursor state for cholesterol gallstone formation is cholesterol-saturated bile. We studied a high-risk group for cholesterol gallstones to determine whether dietary variables affect bile cholesterol. Bile samples were analyzed from 46 Micmac Indian women without gallstones and 13 with gallstones for molar percentage cholesterol (MPC) and bile acid composition. The data were analyzed by multiple regression analysis with MPC

C. Noel Williams; Janice L. Johnston; Sherry McCarthy; C. A. Field



Fatty acid composition and antioxidant system in relation to susceptibility of loquat fruit to chilling injury  

Microsoft Academic Search

Two cultivars of loquat fruit with contrasting chilling resistance were stored at 1°C for 35days to investigate the relationship between chilling injury and fatty acid composition and its antioxidant system. No symptoms of chilling injury occurred in the fruit of ‘Qingzhong’ cultivar during the whole storage, whereas in ‘Fuyang’ fruit, chilling injury increased sharply after 21days of storage at 1°C.

Shifeng Cao; Zhenfeng Yang; Yuting Cai; Yonghua Zheng



Age-dependent fatty acid composition of erythrocyte membrane phospholipids in healthy children  

Microsoft Academic Search

Summary The fatty-acid composition of red-cell-membrane phospholipids (total phospholipids, phosphatidylcholine, and phosphatidylethanolamine fractions) was determined in 88 apparently healthy children aged 1 to 15 years, 10 cord blood samples, and 6 infants below 1 year of age.

M. Laryea; P. Cieslicki; E. Diekmann; U. Wendel



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...


Introducing a traditional dairy product Ke?: Chemical, microbiological, and sensorial properties and fatty acid composition  

Microsoft Academic Search

In this study, it was aimed to determine the chemical, biochemical, microbiological and sensorial characteristics and fatty acid composition of Ke?, traditionally produced in Bolu province in Turkey. The information on production of 'Ke?' was collected from Bolu province in Turkey. Moreover, 20 samples were taken from the local bazaars in different periods in Bolu. These samples were taken to

Hayri Co?kun; T. Ako?lu; M. Fatih; Mustafa Kiralan; Ali Bayrak




Microsoft Academic Search

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

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



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

Microsoft Academic Search

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)

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



Changes in the Amino Acid Composition of Decomposing Plant Materials in Soil: Species and Depth Effects  

Microsoft Academic Search

This project studied the amino acid composition of samples taken from an experiment of in situ incubation of plant debris, mixed with mineral earth, to identify changes during decomposition. Medicago sativa debris, and Eucalyptus globulus and Pinus halepensis ground litter, were mixed with a OM?poor mineral earth, and buried in the soil at 5, 20, and 40 cm depth, for 2

Pere Rovira; Pilar Fernàndez; V. Ramón Vallejo



Amino acid composition of pig meat in relation to live weight and sex  

Microsoft Academic Search

The objective of this study was to find out the amino acid composition of pig meat in relation to live weight and sex. In total 80 (40 barrows\\/40 gilts) finishing pigs of the final hybrid kept in the Czech Republic ((CL × CLW) × (D × PN)) = ((Czech Landrace × Czech Large White) × (Duroc × Pietrain)) were used

M. Okrouhlá; R. Stupka; J. ?ítek; E. Kluzáková Šprysl; M. Trnka; L. Štolc


DNA Asymmetric Strand Bias Affects the Amino Acid Composition of Mitochondrial Proteins  

Microsoft Academic Search

Variations in GC content between genomes have been extensively documented. Genomes with comparable GC con- tents can, however, still differ in the apportionment of the G and C nucleotides between the two DNA strands. This asymmetric strand bias is known as GC skew. Here, we have investigated the impact of differences in nucleotide skew on the amino acid composition of

Xiang JIA MIN; Donal A. HICKEY



Gibberellic acid (GA3) effects on late season grapefruit peel oil composition  

Technology Transfer Automated Retrieval System (TEKTRAN)

Gibberellic acid (GA3) is commonly applied to citrus fruit in the late summer/early autumn to delay peel maturation and extend late season quality. The effect of August/September GA3 application on oil gland composition of "Marsh" white grapefruit harvested in March 18 and April 16 from three groves...


Fatty acid composition of edible oils derived from certified organic and conventional agricultural methods  

Microsoft Academic Search

The objective of this study is to compare the fatty acid composition of commercially available edible oils derived from certified organic and conventional agricultural methods. A total of 59 certified organic and 53 conventional oils were purchased from retail markets in Sydney, Australia. Organic and conventional products were matched for comparison according to the description of production methods, labelled total

Samir Samman; Jessa W. Y. Chow; Meika J. Foster; Zia I. Ahmad; Jenny L. Phuyal; Peter Petocz




Microsoft Academic Search

Fatty acid composition of total lipid extracts of muscle and adipose samples from crossbred bulls (N = 34) and steers (N = 35) was determined by gas-liquid chromatography. Samples of semitendinosus, triceps brachii and longissimus muscle and of subcutaneous and perinephric adipose tissue were excised from the right side of each carcass. In addition, thin-layer chroma- tography was utilized to

Jeffrey M. Eichhorn; Curtiss M. Bailey; Gary J. Blomquist



The amino acid and sugar composition of diatom cell-walls  

Microsoft Academic Search

The cell walls of diatoms consist of a silica frustule encased in an organic coating. Biochemical characterization of this coating should allow insight into: (1) the mechanism of silicification; (2) taxonomy and evolution of diatoms; (3) preservation of fossil frustules. The amino acid and sugar composition of cell walls from 6 diatom species have been elucidated. When compared to cellular

R. E. Hecky; K. Mopper; P. Kilham; E. T. Degens



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

PubMed Central

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.

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



Fatty acid composition of habitual omnivore and vegetarian diets.  


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

Mann, Neil; Pirotta, Yvonne; O'Connell, Stella; Li, Duo; Kelly, Fiona; Sinclair, Andy



Protein and amino acid composition of silks from the cob weaver, Latrodectus hesperus (black widow).  


The silks from the cob weaving spider, Latrodectus hesperus (black widow), have been examined with the goal of expanding our understanding of the relationship between the protein structure and mechanical performance of these unique biomaterials. The scaffolding, dragline and inner egg case silks each appear to be distinct fibers based on mole percent amino acid composition and polypeptide composition. Further, we find that the amino acid composition of dragline and egg case silk are similar to the analogous silks produced by orb weaving spiders, while scaffolding silk may represent a novel silk. The black widow silks are comprised of multiple high molecular weight polypeptides, however, the egg case and scaffolding silks also contain some smaller polypeptides. PMID:10342753

Casem, M L; Turner, D; Houchin, K


Gastrointestinal osmolality electrolyte and organic acid composition in five species of East African herbivorous mammals.  


inherent differences observed in ionic composition of gastrointestinal contents due to diet, feeding regimen and (or) site along the length of the digestive tract were controlled so that a clearer understanding of species differences could be obtained. Three species of ruminants (i.e., Zebu cattle, sheep and goat), a pseudo-ruminant (camel) and a nonruminant (donkey) were compared. Specific differences were observed in organic acid concentration, pH and electrolyte composition at various sites along the length of the tract. In general, Zebu cattle exhibited major differences in colonic volatile fatty acid, sodium and chloried concentrations when compared to other species. Donkeys, camels, sheep and goates were generally similar in their gastrointestinal ionic composition. PMID:7462117

Maloiy, G M; Clemens, E T



Dietary lipids and forages interactions on cow and goat milk fatty acid composition and sensory properties.  


This review summarises the known effects of dietary factors on bovine and caprine milk fatty acid composition, as well as the regulation of cow and goat mammary lipid secretion. Special attention is given to fatty acids that could play a role for human health, such as saturated fatty acids, oleic acid, n-6- or n-3-C18 to C22 polyunsaturated fatty acids, trans isomers of C18:1 and C18:2, and isomers of conjugated linoleic acid (CLA). The main dietary factors taken into account are the nature of forages, including pasture, the forage:concentrate ratio and diet starch content, and the supplementation of dairy rations with crude or processed vegetable oils or oilseeds, and vitamin E. A particular emphasis is given to studies on interactions between these dietary factors, which show that there is a considerable plasticity of ruminant milk fatty acid composition. Despite the existence of several studies on the effects of dietary factors on the sensorial quality of milk and dairy products, there is a need to evaluate more deeply how the different feeding strategies could change the nutritional, sensorial and technological aspects of milk fat quality. PMID:15636165

Chilliard, Yves; Ferlay, Anne


[Disorders of fatty acid composition and the processes of lipid peroxidation in chronic ischemic heart disease].  


The levels of lipid fractions, free and bound fatty acids, initial and end lipid peroxidation products in the blood plasma, red cell membrane resistance to hemolysis, and myocardial contractility before, during, and after therapy with lipostabil forte (0.6-1.8 g daily or 10 ml (0.5 g) i.v.) and bezafibrate (0.2 g 3 times daily) along with nitrates (10 to 30 tablets) have been examined by the routine methods in 159 patients with stable angina pectoris and postinfarction cardiosclerosis. A negative effect of high doses of nitrates on myocardial hemodynamics and fatty acid composition has been revealed, resulting in accumulation of bound fatty acids. Lipostabil has improved the patients' status, myocardial function, and lipid composition, reduced the levels of atherogenic lipids and lipid peroxidation products, as well as the concentration of fatty acids with an uneven number of C atoms, increased the fatty acid nonsaturation index and the level of medium-strand fatty acids. Improvement of the patient's condition in bezafibrate therapy has been less evident; the concentration of atherogenic lipids has been reduced, but the levels of bound fatty acids and of lipid peroxidation products has increased. Bezafibrate is recommended to be administered together with antioxidants. PMID:2762920

Kalmykova, V I; Zakharova, E V



Fatty acid compositions of Taenia solium metacestode and its surrounding tissues.  


Fatty acids (FAs) are the main energy sources of living organisms and are the major components of cellular and organelle membranes. Their compositions also affect the flexibility/rigidity of cells and cell vitality. The Taenia solium metacestode (TsM) causes neurocysticercosis (NC), which is one of the most common helminthic infections of the central nerve system. We investigated the FA composition of the cyst fluid (CF) and parenchyma of the TsM, together with those of the granuloma and swine tissue surrounding the granuloma. The FA fractions of the TsM CF and swine tissue showed a composition and proportional contents comparable to each other, in which C18:0 (stearic acid), C18:1n9c (oleic acid), C20:4 (arachidonic acid) and C16:0 (palmitic acid) constituted the major fractions. However, the relative amount of individual FAs of the TsM parenchyma and granuloma differed from those of TsM CF and swine tissue, which contained enriched C16:0 and a lower amount of C20:4. Saturated FAs were the major constituents in parenchyma and granuloma, 50.4% and 46.1%, respectively. Conversely, monounsaturated FAs were the major constituents of CF and swine tissue, 38.7% and 40.3%, respectively. Our results strongly suggest that host-derived FAs might translocate across the parasite syncytial membrane and be stored in the CF. PMID:22971473

Kim, Seon-Hee; Bae, Young-An; Nam, Jin-Sik; Yang, Yichao; Nawa, Yukifumi; Kong, Yoon



Use of super acids to digest chrysotile and amosite asbestos in simple mixtures or matrices found in building materials compositions  

SciTech Connect

A composition for converting asbestos-containing material to environmentally benign components is provided. The composition comprises a fluoro acid decomposing agent which can be applied to either amosite-containing thermal insulation or chrysotile-containing fire-proof material or to any asbestos-containing material which includes of chrysotile and amosite asbestos. The fluoro acid decomposing agent includes FP{sub 0}(OH){sub 2}, hexafluorophosphoric acid, a mixture of hydrofluoric and phosphoric acid and a mixture of hexafluorophosphoric acid and phosphoric acid. A method for converting asbestos-containing material to environmentally benign components is also provided.

Sugama, T.; Petrakis, L.; Webster, R.P.



Effect of ocean acidification on the fatty acid composition of a natural plankton community  

NASA Astrophysics Data System (ADS)

The effect of ocean acidification on the fatty acid composition of a natural plankton community in the Arctic was studied in a large-scale mesocosm experiment, carried out in Kongsfjorden (Svalbard, Norway) at 79° N. Nine mesocosms of ~50 cbm each were exposed to different pCO2 levels (from natural background conditions to ~1420 ?atm), yielding pH values (on the total scale) from ~8.3 to 7.5. Inorganic nutrients were added on day 13. The phytoplankton development during this 30 days experiment passed three distinct phases: (1) prior to the addition of inorganic nutrients, (2) first bloom after nutrient addition, and (3) second bloom after nutrient addition. The fatty acid composition of the natural plankton community was analysed and showed, in general, high percentages of polyunsaturated fatty acids (PUFAs): 44-60% of total fatty acids. Positive correlations with pCO2 were found for most PUFAs during phases 2 and/or 3, with the exception of 20:5n3 (eicosapentaenoic acid, EPA), an important diatom marker. There are strong indications for these correlations being mediated indirectly through taxonomic changes and the natural development of the communities in the mesocosms exposed to different pCO2 levels. While diatoms increased during phase 3 mainly in the low and intermediate pCO2 treatments, dinoflagellates were favoured by high CO2 concentrations during the same time period. This is reflected in the development of group-specific fatty acid trophic markers. No indications were found for a generally detrimental effect of ocean acidification on the planktonic food quality in terms of essential fatty acids. The significant positive correlations between most PUFAs and pCO2 reflected treatment-dependent differences in the community composition between the mesocosms rather than a direct positive effect of pCO2 on specific fatty acids.

Leu, E.; Daase, M.; Schulz, K. G.; Stuhr, A.; Riebesell, U.



Essential-oil and fatty-acid composition, and antioxidant activity of extracts of Ficaria kochii.  


The essential-oil and fatty-acid composition of the aerial parts of Ficaria kochii (Ledeb.) Iranshahr & Rech.f. native to Iran, and the antioxidant activity of various extracts of this plant were examined. The study by GC-FID and GC/MS analysis of the essential oil resulted in the identification of 61 compounds, representing 86.01% of the total oil composition. Phytol (10.49%), farnesol (7.72%), methyl linoleate (5.57%), and ?-farnesene (4.96%) were the main components. The fatty-acid composition of the aerial parts of F. kochii was also analyzed by GC/MS. The major components were palmitic acid (25.9%), linolenic acid (25.3%), and linoleic acid (17.5%). Polyunsaturated fatty acids (PUFAs) were found in higher amounts than saturated fatty acids. The possible antioxidant activity of various extracts (prepared by using solvents with different polarity) of the F. kochii aerial parts was evaluated by screening for their 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity, Fe(III) -reducing power, total antioxidant activity, and inhibitory activity in the linoleic acid-peroxidation system. H(2) O proved to be the most efficient solvent for the extraction of antioxidants, as the H(2) O extract contained the highest amount of phenolic compounds (2.78±0.23 GAE/g dry matter) and also exhibited the strongest antioxidant capacity in all the assays used. The results of the present investigation demonstrated that the aerial parts of F. kochii can be used as natural and safe nutrition supplement in place of synthetic ones. PMID:23255443

Tavakoli, Rahmatollah; Mohadjerani, Maryam; Hosseinzadeh, Rahman; Tajbakhsh, Mahmood; Naqinezhad, Alireza



Can the fatty acid selectivity of plant lipases be predicted from the composition of the seed triglyceride?  

Microsoft Academic Search

To address the question can the fatty acid selectivity of plant lipases be predicted from the composition of the seed triglyceride, we have characterised the selectivity of lipases from a wide range of oilseeds with diverse fatty acid compositions. For this study, a novel hydrolysis assay using a fully randomised oil, was developed. From some seed sources (e.g. Cinnamomum camphora),

Susan Amanda Hellyer; Ian Christopher Chandler; John Anthony Bosley



Lipid class and fatty acid composition of brain lipids from Atlantic herring ( Clupea harengus ) at different stages of development  

Microsoft Academic Search

Little is known about the changes in composition of brain lipids and fatty acids at different stages of development in fish. Wild Atlantic herring (Clupea harengus L.) were collected from Loch Linnhe and the Firth of Clyde, Scotland, from August 1990 to March 1991. Lipid class and fatty acid compositions of brain lipids were studied at four different stages of

G. Mourente; D. R. Tocher



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

Microsoft Academic Search

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

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



Influence of Fatty Acid Composition in Dried Raw Mink and Blue Fox Skins on Their Storage Aging and Dressing Properties  

Microsoft Academic Search

The influence of fatty acid composition in dried raw mink and blue fox skins on their storage aging and dressing properties was assessed. The parameters studied were: changes in the fatty acid composition of the skins during one year's cold storage (+8°C, 70% RH), swelling, tannin fixation and such mechanical characteristics as tensile strength and tearing strength in fresh and

Kirsti Rouvinen; Esa Mäntysalo



[The study of fatty acid composition of terpug during preserve's production].  


The results of research of fatty acids composition of Terpug, during the producing of preserves in souses and aspics, which are got using the method of gas liquid chromatography. It is known that during the marinating process of Terpug there is no the oxidizing destruction of lipids of muscular tissue of fish. The kind of aspic influences on fatty acids composition of preserves of Terpug. The process of ripening and storing of preserves of fish leads to the diffusion, in particular the sorption of components of aspic with fish. This process increases nutrient density, proportion W3 cem/W6 cem acids it is close to optimal meaning, testifies to high biological value of preserves. PMID:12872659

Cherevan, E I; Tsybul'ko, E I



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

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

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


Fatty acid and hydrocarbon composition in tropical marine Shewanella amazonensis strain SB2B(T).  


Shewanella amazonensis strain SB2B(T) is an isolate from shallow-water marine sediments derived from the Amazon River delta. This bacterium contained a long-chain polyunsaturated hydrocarbon, all-cis -3,6,9,12,16,19,22,25,28 hentriacontanonaene (C31:9), constituting 1-2% of the total fatty acid methyl ester and hydrocarbon fraction, which was produced dependently of decreased growth temperature. Analysis of its cellular fatty acid composition demonstrated that isopentadecanoic acid was the major fatty acid component and that all the main monounsaturated fatty acids had straight chains with a cis configuration. However, monoenoic cyclopropyl fatty acids, which were previously reported to be present in this bacterium, were not detected by mass spectrometric analysis. The growth temperature affected the content of ?9-cis -hexadecenoic [16:1(?9c)], palmitic, and heptadecanoic acids. These results suggest that C31:9, as well as 16:1(?9c) might be involved in adaptation to low temperature in S. amazonensis strain SB2B(T) . Our result suggests that polyunsaturated fatty acid synthase protein complex may be involved in synthesis of C31:9 but not in production of eicosapentaenoic acid. PMID:21656813

Motoigi, Taro; Okuyama, Hidetoshi



Preparation, thermal properties and thermal reliability of capric acid\\/expanded perlite composite for thermal energy storage  

Microsoft Academic Search

The aim of this research is the preparation of a novel form-stable composite PCM by incorporation of capric acid (CA) within the expanded perlite (EP), characterization of the composite by SEM and FT-IR technique and determination of thermal properties and thermal reliability of the composite PCM using DSC analysis. The maximum proportion of CA as phase change material (PCM) in

Ahmet Sar?; Ali Karaipekli



Hydrogen Isotopic Composition of Particulate-Bound Fatty Acids From the California Borderland Basins  

NASA Astrophysics Data System (ADS)

We examined the hydrogen-isotopic composition of fatty acids associated with particulate organic matter (POM) from depth transects in three California Borderland stations. Our goals were to determine (1) the natural variability of ?D values in POM-associated fatty acids and (2) the magnitude of isotopic fractionations associated with fatty acid degradation in the marine environment. Some differences in molecular abundance were observed between completely ventilated and occasionally suboxic sites, but no corresponding shifts in ?D values were measured. Values of ?D for specific fatty acids were generally consistent between stations. Saturated fatty acids (C14, C16, and C18) yielded ?D values ranging from -230‰ to -132‰, with ?D values generally decreasing with chain length. We found no evidence of extreme D-enrichment of the C18 fatty acid as has been observed in studies of isolated macroalgae (Chikaraishi, et al, 2004). The unsaturated C16 and C18 fatty acids showed a similar trend while the polyunsaturated fatty acid 22:6 was somewhat enriched in D (?D values ranging from -186‰ to -68‰) relative to 20:5 (-208‰ to -93‰). Unsaturated fatty acids tended to have more positive ?D values than their saturated counterparts, opposite the trend observed in sediments from the same location. The bacterial fatty acid C15 showed even greater deuterium enrichment with ?D values ranging from - 145‰ to -88‰. This offset can likely be attributed to differences in biosynthetic fractionation between bacteria and eukaryotes, to differences in hydrogen isotopic composition of the food sources of these organisms, or some combination of these two factors. Within the surface waters, fatty acids become enriched with depth by an average of 25‰. The C18:0 acid is a significant exception, becoming depleted by 48‰ over that same interval. Below 100 meters depth, all fatty acids tend to become slightly depleted in D with increasing depth. The difference in ?D values of a fatty acid at the surface and at depth is only slightly correlated (R2 = 0.4) with the fractional mass lost between surface and deep samples. We infer that degradation of fatty acids in the water column is associated with little or no isotopic fractionation, but that other unknown processes may produce systematic changes in ?D.

Jones, A. A.; Sessions, A. L.; Campbell, B. J.; Valentine, D. L.



[A study on the fatty acid composition of the plasma lipoprotein in patients with fractures].  


Although the etiology of post-traumatic fat embolization still remains obscure, various concepts as to the pathophysiology of the syndrome have emerged in recent years. Extensive studies have indicated that trauma and surgical stress cause remarkable alterations in lipid metabolism. In the following study designed to characterize this situation more fully, the author has analyzed the changes of fatty acid composition of triacylglycerol, phospholipid and cholesterol ester in the circulating plasma lipoprotein of the patient with fractures. Materials and Methods: Ten patients who sustained one or more fractures without chest injury between age 9 and 79 years and seven healthy human subjects as control were selected for study. Blood samples were withdrawn into EDTA-treated syringes from patients after overnight fast at intervals of 2, 3, 4, 5 and 14 days after injury. Lipoprotein fractions (very low density lipoprotein: VLDL, low density lipoprotein: LDL, high density lipoprotein: HDL, and very high density lipoprotein: VHDL) were prepared by the method of ultracentrifugation. Lipids were extracted from the lipoprotein fractions according to the procedure of Folch. Lipids separation and purification were carried out by one-dimension thin-layer chromatography. The purified lipids were methylated with BF3-methanol complex and the fatty acid composition of each lipid fraction was analyzed by gas-liquid chromatography. Results: In the blood samples of normal subjects and patients, myristic, palmitic, palmitoleic, stearic, oleic and linoleic acids (C14: 0, C16: 0, C16: 1, C18: 0, C18: 1 and C18: 2) were the principal fatty acids and these fatty acids were all altered after injury except C14: 0 and C18: 2. The distribution of fatty acids in VLDL-TL was especially altered from the 3rd to 5th hospital day. Stearic acid derived from VLDL-PL was decreased and C18: 1 derived from VLDL-TG was increased. Of the ten patients there were greater changes in those with the femoral fracture. In LDL-TL, the distribution of fatty acids was also altered, and C18:1 derived from LDL-TG was increased. In fatty acid composition of HDL-TL, C16: 0 derived from HDL-PL and C18: 1 derived from HDL-TG were increased and C18: 0 derived from HDL-PL was decreased. In fatty acid composition of VHDL-TL, C16: 1 derived from VHDL-TG was increased. PMID:6491425

Nara, C



Effect of ocean acidification on the fatty acid composition of a natural plankton community  

NASA Astrophysics Data System (ADS)

The effect of ocean acidification on the fatty acid composition of a natural plankton community in the Arctic was studied in a large-scale mesocosm experiment, carried out in Kongsfjorden (Svalbard, Norway) at 79° N. Nine mesocosms of ~50 m3 each were exposed to 8 different pCO2 levels (from natural background conditions to ~1420 ?atm), yielding pH values (on the total scale) from ~8.3 to 7.5. Inorganic nutrients were added on day 13. The phytoplankton development during this 30-day experiment passed three distinct phases: (1) prior to the addition of inorganic nutrients, (2) first bloom after nutrient addition, and (3) second bloom after nutrient addition. The fatty acid composition of the natural plankton community was analysed and showed, in general, high percentages of polyunsaturated fatty acids (PUFAs): 44-60% of total fatty acids. Positive correlations with pCO2 were found for most PUFAs during phases 2 and/or 3, with the exception of 20:5n3 (eicosapentaenoic acid, EPA), an important diatom marker. These correlations are probably linked to changes in taxonomic composition in response to pCO2. While diatoms (together with prasinophytes and haptophytes) increased during phase 3 mainly in the low and intermediate pCO2 treatments, dinoflagellates were favoured by high CO2 concentrations during the same time period. This is reflected in the development of group-specific fatty acid trophic markers. No indications were found for a generally detrimental effect of ocean acidification on the planktonic food quality in terms of essential fatty acids.

Leu, E.; Daase, M.; Schulz, K. G.; Stuhr, A.; Riebesell, U.



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


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 determined the effects of chronic treatment with the atypical antipsychotic risperidone (RISP, 3.0 mg/kg/d) on erythrocyte and PFC omega-3 fatty acid composition in rats maintained on a diet with or without the dietary omega-3 fatty acid precursor, alpha-linolenic acid (ALA, 18:3n-3). Chronic RISP treatment resulted in therapeutically-relevant plasma RISP and 9-OH-RISP concentrations (18+/-2.6 ng/ml), and significantly increased erythrocyte docosahexaenoic acid (DHA, 22:6n-3, +22%, p=0.0003) and docosapentaenoic acid (22:5n-3, +18%, p=0.01) composition, and increased PFC DHA composition (+7%, p=0.03) in rats maintained on the ALA+ diet. In contrast, chronic RISP did not alter erythrocyte or PFC omega-3 fatty acid composition in rats maintained on the ALA- diet. Chronic RISP treatment did not alter erythrocyte or PFC arachidonic acid (AA, 20:4n-6) composition. These data suggest that chronic RISP treatment significantly augments ALA-DHA biosynthesis, and preferentially increases peripheral and central membrane omega-3 fatty acid composition. Augmented omega-3 fatty acid biosynthesis and membrane composition represents a novel mechanism of action that may contribute in part to the efficacy of RISP in the treatment of SZ. PMID:18993032

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



Interaction of vanadate (H/sub 2/VO/sub 4//sup /minus//) with dipeptides investigated by /sup 51/V NMR spectroscopy  

SciTech Connect

The complexation of vanadates by dipeptides has been studied, and the results are reported herein. The simple dipeptides selected with respect to the elucidation of their mode of coordination contained glycine at the N-terminal end. It is also known that acidic side chains of the protein matrix are likely to be involved in the vanadate coordination in vanadate-dependent peroxidase. At pH 7.5 and at overall vanadium concentrations of 10 mmol/L, the species present in solution are H/sub 2/VO/sub 4//sup /minus//, H/sub 2/V/sub 2/O/sub 7//sup /minus//, V/sub 4/O/sub 12//sup 4/minus//, and V/sub 5/O/sub 15//sup 5/minus//. Another possible species present is V/sub 6/O/sub 18//sup 6/minus//. /sup 51/V NMR spectroscopy was used to elucidate the vanadate species. 27 refs., 3 figs., 2 tabs.

Rehder, D.



Molecular recognition of N-protected dipeptides by pseudopeptidic macrocycles: a comparative study of the supramolecular complexes by ESI-MS and NMR.  


The molecular recognition properties of pseudopeptidic macrocycles have been studied by ESI-MS and NMR spectroscopy, as highly complementary experimental techniques in solution and in the gas phase. We used ESI-MS competition experiments for the high throughput screening of the supramolecular interaction between four macrocyclic receptors and different peptide-like substrates in solution, rendering the best-fitted host-guest pairs. Further insights on the non-covalent recognition process in the gas-phase were obtained through collision induced dissociation (CID) experiments. Solution studies using NMR spectroscopy ((1)H NMR titrations, NOESY and DOSY) were carried out to prove the validity of ESI-MS as a high-throughput screening method for studying the molecular recognition of the investigated pseudopeptidic macrocycles. A clear selectivity for N-protected dipeptides over N-protected amino acids, and a slight preference for dipeptides bearing aromatic side chains were observed. On the basis of the results obtained from this approach, a mode of binding has been proposed. PMID:20204204

Alfonso, Ignacio; Bolte, Michael; Bru, Miriam; Burguete, M Isabel; Luis, Santiago V; Vicent, Cristian



Formation of titanium phosphate composites during phosphoric acid decomposition of natural sphene  

NASA Astrophysics Data System (ADS)

Decomposition of mineral sphene, CaTiOSiO4, by H3PO4 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(HPO4)2·H2O 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(HPO4)2·H2O proceeds via formation of meta-stable titanium phosphate phases, Ti(H2PO4)(PO4)·2H2O and Ti(H2PO4)(PO4). The sorption affinities of TiP composites were examined in relation to caesium and strontium ions. A decrease of H3PO4 concentration leads to formation of composites with greater sorption properties. The maximum sorption capacity of TiP is observed when 60% H3PO4 is used in sphene decomposition. The work demonstrates a valuable option within the Ti(HPO4)2·H2O SiO2 composite synthesis scheme, to use phosphoric acid flows for isolation of CaHPO4·2H2O fertilizer.

Maslova, Marina V.; Rusanova, Daniela; Naydenov, Valeri; Antzutkin, Oleg N.; Gerasimova, Lidia G.



Shear thickening compositions containing polyacrylic acid and polyacrylamide, their preparation and use  

SciTech Connect

A process is described for plugging a portion of a well bore using a shear-thickening composition and a emulsion spacer where a conduit, which contains a fluid, extends down into a well bore from the surface to at least that portion to be plugged and where the shear-thickening composition comprises a water-in-oil emulsion having particles of hydratable, water-expandable clay dispersed in the continuous oily phase. The oily phase comprises a hydrocarbon liquid having a surfactant dissolved in which surfactant comprises a polyamine attached to an oil solubilizing hydrocarbon with or without an intervening bridging group and where the dispersed aqueous phase of the emulsion comprises an aqueous polymer solution, having a pH below 7, of both a polyacrylic acid and polyacrylamine. The spacer comprises a water-in-oil emulsion having a composition similar to the water-in-oil emulsion of the shear-thickening composition and each droplet of dispersed aqueous phase of the shear-thickening composition is encapsulated in a film which forms as a result of the interaction of the polyacrylic acid, surfactant and polyacrylamide.

Eustace, D.J.; Siano, D.B.; Drake, E.N.; Calcavecchio, P.



The classification of various organisms according to the free amino acid composition change as the result of biological evolution  

Microsoft Academic Search

Summary.   The free amino acid compositions in archaeobacteria, eubacteria, protozoa, blue-green alga, green alga, slime mold, plants\\u000a and mammalian cells were analyzed, to investigate whether changes in their free amino acid compositions reflect biological\\u000a evolution. Cell homogenates were treated with 80–90% ethanol to separate cellular proteins and free amino acids contained\\u000a in the cells. Different patterns of the free amino

K. Sorimachi



Seasonal variations in fatty acid composition of pasture forage plants and CLA content in ewe milk fat  

Microsoft Academic Search

The relations between fatty acids (FAs) composition of pasture forage plants and the content of conjugated linoleic acid (CLA) as a total content of cis-9, trans-11+trans-7, cis-9+trans-8, cis-10 CLA isomers in ewes’ milk fat during natural pasture season (April–September) were investigated. The extracts of ewes’ milk fat samples as well as the pasture samples were analyzed for fatty acid composition

B. Me?uchová; J. Blaško; R. Kubinec; R. Górová; J. Dubravská; M. Margetín; L. Soják



Influence of salt concentration on the cellular fatty acid composition of the moderately halophilic bacterium Halomonas salina  

Microsoft Academic Search

The cellular fatty acid composition of Halomonas salina, a moderately halophilic bacterium grown at different salt concentrations, is reported. Fatty acids C16:0 and C18:1 were major components and significant amounts of C16:1, C18:0 and cyc-C19:0 were also detected. The results showed clear chemotaxonomic relationships with recognized members of the genus Halomonas. The salt concentration greatly influenced the fatty acid composition,

M. J Valderrama; M Monteoliva-Sanchez; E Quesada; A Ramos-Cormenzana



Fatty acid composition and lipoxygenase metabolism in blood cells of the lesser spotted dogfish, Scyliorhinus canicula.  


1. The fatty acid composition of erythrocytes and leucocytes of the elasmobranch, Scyliorhinus canicula, was determined so as to indicate substrate availability for eicosanoid formation. 2. Leucocytes showed a greater degree of fatty acid unsaturation than the erythrocytes, with particularly high levels of docosahexaenoic acid (22:6,n-3). 3. The major eicosanoid precursors, arachidonic acid (20:4,n-6) and eicosapentaenoic acid (20:5,n-3), represented 13.9% and 5.2% of the total fatty acid, respectively, in erythrocytes compared with 10.7% and 6% in leucocytes. 4. Whole blood and isolated leucocytes were stimulated with calcium ionophore, A23187 and the resulting lipoxygenase products separated by reverse phase high performance liquid chromatography. 5. The main lipoxygenase products formed were 6-trans-leukotriene B4, 6-trans-12-epi-leukotriene B4, 5(S),6(R) dihydroxyeicosatetraenoic acid and 5- and 15-hydroxyeicosatetraenoic acid. 6. No leukotriene B4, leukotriene B5, or lipoxins were detected. PMID:1769212

Pettitt, T R; Rowley, A F



Fatty acids composition in seeds of the South American glasswort Sarcocornia ambigua.  


Sarcocornia ambigua (Michx.) M.A. Alonso & M.B. Crespo is the most widely distributed species of the perennial genus of glasswort in South America, and it shows great biotechnological potential as a salt-water irrigated crop. Qualitative and quantitative compositions of fatty acids were determined in the seeds of S. ambigua that were cultivated in southern Brazil. Hexane extraction of the seed oil from S. ambigua yielded 13% of total lipids. The GC-FID (Gas Chromatography Flame Ionization Detector) analysis of the hexane extracts showed five prominent peaks for the seed oil: 42.9 wt.% linoleic-?6 acid (18:2), 20.4 wt.% palmitic acid (16:0), 18.5 wt.% oleic acid (18:1), 4.5 wt.% stearic acid (18:0) and 4.0 wt.% linolenic-?3 acid (18:3). The sum of the saturated palmitic and stearic acids (24.8%) in S. ambigua seed oil exceeded values cited for commercial oils use, as well as the seed oil from the cultivated annual glasswort Salicornia bigelovii. No undesirable fatty acid components were found in S. ambigua seed oil, and it could be recommended for animal consumption or biofuel production. PMID:22801376

D'oca, Marcelo G M; Morón-Villarreyes, Joaquín A; Lemões, Juliana S; Costa, César S B



Environment-controlled interchromophore charge transfer transitions in dipeptides probed by UV Absorption and electronic circular dichroism spectroscopy.  


Charge transfer (CT) transitions between the C-terminal carboxylate and peptide group have been investigated for alanyl-X and X-alanine dipeptides by far-UV absorption and electronic circular dichroism (ECD) spectroscopy (where X represents different amino acid residues). The spectra used in the present study were obtained by subtracting the spectrum of the cationic species from that of the corresponding zwitterionic peptide spectrum. These spectra displayed three bands, e.g., band I between 44 and 50 kK (kK = 10(3) cm(-1)), band II at 53 kK, and band III above 55 kK, which were, respectively, assigned to a n(COO-) --> pi* CT transition, a pi(COO-) --> pi* CT transition, and a carboxylate pi --> pi* (NV1) transition, respectively By comparison of the intensity, bandwidth, and wavenumber position of band I of some of the investigated dipeptides, we found that positive charges on the N-terminal side chain (for X = K), and to a minor extent also the N-terminal proton, reduce its intensity. This can be understood in terms of attractive Coulomb interactions that stabilize the ground state over the charge transfer state. For alanylphenylalanine, we assigned band I to a n(COO-) --> pi* CT transition into the aromatic side chain, indicating that aromatic side chains interact electronically with the backbone. We also performed ECD measurements at different pH values (pH 1-6) for a selected subset of XA and AX peptides. By subtraction of the pH 1 spectrum from that observed at pH 6, the ECD spectrum of the CT transition was obtained. A titration curve of their spectra reveals a substantial dependence on the protonation state of the aspartic acid side chain of AD, which is absent in DA and AE. This most likely reflects a conformational transition of the C-terminus into a less extended state, though the involvement of a side chain --> peptide CT transition cannot be completely ruled out. PMID:16805637

Dragomir, Isabelle C; Measey, Thomas J; Hagarman, Andrew M; Schweitzer-Stenner, Reinhard



Fatty acid composition of lipids in pot marigold (Calendula officinalis L.) seed genotypes  

PubMed Central

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.



Lipid and fatty acid compositions of cod ( Gadus morhua), haddock ( Melanogrammus aeglefinus) and halibut ( Hippoglossus hippoglossus)  

NASA Astrophysics Data System (ADS)

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.

Zeng, Duan; Mai, Kangsen; Ai, Qinghui; Milley, Joyce E.; Lall, Santosh P.



Dietary fat in relation to erythrocyte Fatty Acid composition in men.  


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

Takkunen, Markus; Agren, Jyrki; Kuusisto, Johanna; Laakso, Markku; Uusitupa, Matti; Schwab, Ursula



Candidate gene expression affects intramuscular fat content and fatty acid composition in pigs.  


The objective of this study was to correlate the expression pattern of candidate genes with the intramuscular fat (IMF) content and fatty acid composition of the Longissimus dorsi muscle of Duroc × Shanzhu commercial crossbred pigs. Animals of both sexes were slaughtered at a body weight of about 90 kg. The IMF content and fatty acid composition of the Longissimus dorsi muscle were measured and correlated with candidate genes mRNA expression (AdPLA, ADRB3, LEPR, MC4R, PPAR?, PPAR?, LPL, PEPCK, and SCD). Females presented higher IMF content (p < 0.05) than males. The total saturated fatty acid (SFA) in males was greater (p < 0.01), whereas the total monounsaturated fatty acid (MUFA) (p < 0.01) and polyunsaturated fatty acid (PUFA) (p < 0.05) were lower than in females. The expressions of AdPLA, MC4R, PEPCK, and SCD correlated with the IMF content (p < 0.05). AdPLA showed a positive association with MUFA and a negative association with SFA (p < 0.05). LEPR and MC4R were both positively and significantly associated with C18:3 and C20:0 (p < 0.05). PPAR? and PPAR? were negatively correlated with SFA, and PPAR? was positively associated with MUFA (p < 0.05). LPL was positively associated with MUFA and negatively associated with SFA (p < 0.05). PEPCK was negatively correlated with PUFA (p < 0.05). SCD was positively associated with MUFA (p < 0.05). The revealed correlations may confirm that these candidate genes are important for fat deposition and fatty acid composition in pigs, and the evaluation and use of these genes may be useful for improving porcine meat quality. PMID:23275256

Wang, Wei; Xue, Wenda; Jin, Bangquan; Zhang, Xixia; Ma, Fei; Xu, Xiaofeng



Composition of fatty acids in plasma and erythrocytes and eicosanoids level in patients with metabolic syndrome  

PubMed Central

Background Disturbances of the fatty acids composition in plasma and red blood cells and eicosanoid synthesis play an important role in the metabolic syndrome (MS) formation. Methods The observation group included 61 people with metabolic syndrome (30 patients with MS and normal levels of insulin, 31 people with MS and insulin resistance - IR). The parameters of carbohydrate and lipid metabolism in blood serum were examined. The composition of nonesterified fatty acids (NEFA), fatty acid (FA) of red blood cells lipids was analyzed by gas-liquid chromatography. Eicosanoids level in MS patients blood serum was studied by enzyme immunoassay. Results In MS patients in the absence of glucose-insulin homeostasis disturbances and in patients with IR the accumulation of polyunsaturated fatty acids (18:2 n6, 18:3 n3, 22:4 n6) and lower pool of saturated FA (12:0, 14:0, 16: 0, 17:0) in plasma were discovered. A deficit of polyunsaturated FA (18:3 n3, 20:4 n6) with a predominance of on-saturated FA (14:0, 18:0) in erythrocyte membranes was revealed. In MS patients regardless of the carbohydrate metabolism status high levels of leukotriene B4 and 6-keto-prostaglandin-F1? in serum were found. The development of IR in MS patients leads to increased synthesis of thromboxane A2. Conclusion The results revealed a disturbance in nonesterified fatty acids of plasma lipids and red blood cells, eicosanoid synthesis in MS patients. The breach of the plasma and cell membranes fatty acids compositions, synthesis of vasoactive and proinflammatory eicosanoids is an important pathogenetic part of the MS development.



Effect of phytic acid and microbial phytase on the flow and amino acid composition of endogenous protein at the terminal ileum of growing broiler chickens.  


The effects of phytic acid and microbial phytase on the flow and composition of endogenous protein at the terminal ileum of broiler chickens were investigated using the peptide alimentation method. Phytic acid (fed as the sodium salt) was included in a synthetic diet at 8.5, 11.5 and 14.5 g/kg (or 2.4, 3.2 and 4.0 g/kg phytate-phosphorus) and each diet was fed without or with an Escherichia coli-derived microbial phytase at 500 phytase units/kg diet. A control containing no phytate was fed as a comparison to estimate basal endogenous flows. Ingestion of phytic acid increased (P < 0.05) the flow of endogenous amino acids and N by an average of 47 % at the lowest phytic acid concentration and 87 % at the highest. The addition of microbial phytase reduced (P < 0.05) the inimical effects of phytic acid on endogenous amino acid flow at all dietary phytic acid levels. The composition of endogenous protein was also influenced (P < 0.10-0.001) by increasing phytic acid concentrations and phytase addition. The effects of phytic acid and phytase on endogenous flow and composition of endogenous protein, however, varied depending on the amino acid. It is concluded that the effects of phytase on amino acid digestibility may be mediated, in part, through a route of reduced endogenous loss. PMID:17524177

Cowieson, A J; Ravindran, V



A quantitative comparison between diet and body fatty acid composition in wild northern pike ( Esox lucius L.)  

Microsoft Academic Search

The fatty acid compositions of wild female northern pike (Esox lucius L.) and their principle prey species were compared to assess the extent to which pike modify the relative abundance of dietary fatty acids during assimilation and to indicate the optimum dietary content of essential fatty acids (EFAs) for pike. Only minor differences existed between the estimated whole body fatty

Karl Schwalmel



Polyaniline–silver composites prepared by the oxidation of aniline with silver nitrate in solutions of sulfonic acids  

Microsoft Academic Search

Aniline was oxidized with silver nitrate in aqueous solutions of sulfonic acids: camphorsulfonic, methanesulfonic, sulfamic, or toluenesulfonic acids. Polyaniline–silver composites were produced slowly in 4 weeks in good yield, except for the reaction, which took place in sulfamic acid solution, where the yield was low. Polyaniline in the emeraldine form was identified with UV–visible, FTIR, and Raman spectra. Thermogravimetric analysis

Patrycja Bober; Miroslava Trchová; Jan Prokeš; Martin Varga; Jaroslav Stejskal



Influence of salt concentration and temperature on the fatty acid compositions of Ectothiorhodospira and other halophilic phototrophic purple bacteria  

Microsoft Academic Search

Influences of the salt concentration on the fatty acid composition of Ectothiorhodospira species and other phototrophic purple bacteria have been analysed. Major fatty acids in bacteria of the genera Rhodobacter, Rhodopseudomonas, Chromatium, and Ectothiorhodospira were straight chain saturated and monounsaturated C-16 and C-18 fatty acids. Salt-dependent responses of