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Sample records for acid composition determined

  1. Determination of antioxidant capacity, phenolic acids, and fatty acid composition of rapeseed varieties.

    PubMed

    Szydłowska-Czerniak, Aleksandra; Trokowski, Konrad; Karlovits, György; Szłyk, Edward

    2010-07-14

    Three different analytical methods: ferric-reducing antioxidant power (FRAP), 2,2'-diphenyl-1-picrylhydrazyl (DPPH), and oxygen radical absorbance capacity (ORAC) were used for determination of antioxidant capacity of seven rapeseed varieties. Antioxidant capacity and levels of the total phenolic content, individual phenolic acids, fatty acid composition, and the selected physicochemical properties of the studied rapeseed cultivars were determined. Mean ORAC values for methanolic extracts of rapeseeds (4092-12989 mmol of Trolox/100 g) were significantly higher than FRAP and DPPH values (6218-7641 and 6238-7645 mumol of Trolox/100 g, respectively). Although FRAP and DPPH results were lower than ORAC values for all studied rapeseed varieties, there are linear and significant correlations between these three analytical methods (correlation coefficients ranged between 0.9124 and 0.9930, p < 0.005). Also, total phenolic compounds in rapeseeds correlated with antioxidant capacity (correlation coefficients ranged between 0.8708 and 0.9516, p < 0.01). Total phenolic acids determined by HPLC varied from 20.3 mg to 40.7 mg per 100 g of rapeseed flour, and the main phenolic acid is sinapic acid (17.4-36.4 mg/100 g). Fatty acid composition (SAFA = 7.2-8.6%, MUFA = 58.5-68.0%, PUFA = 24.7-33.9%) and the absence of trans-fatty acids indicate that the studied rapeseed varieties can be a source of unsaturated fatty acids and have a positive impact on human health.

  2. Determination of fatty acid composition and quality characteristics of oils from palm fruits using solvent extraction

    NASA Astrophysics Data System (ADS)

    Kasmin, Hasimah; Lazim, Azwan Mat; Awang, Roila

    2015-09-01

    Palm oil contains about 45% of saturated palmitic acid and 39% of mono-unsaturated oleic acid. Investigations made in the past to trace the fatty acid composition in palm revealed that ripeness of fresh fruit bunch (FFB) affect oil composition. However, there is no evidence that processing operations affect oil composition, although different stage of processing does affect the quality of oil extracted. An improved method for sterilizing the oil palm fruits by dry heating, followed by oil extraction has been studied. This method eliminates the use of water, thus, increasing the extraction of lipid soluble. The objective of this study is to determine the possibility production of palm oil with different fatty acid composition (FAC) as well as the changes in quality from conventional milling. The unripe and ripe FFB were collected, sterilized and extracted using different method of solvent extraction. Preliminary data have shown that variation in FAC will also alter the physical and chemical properties of the oil extracted.

  3. Determination of fatty acid composition of γ-irradiated hazelnuts, walnuts, almonds, and pistachios

    NASA Astrophysics Data System (ADS)

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

    2011-04-01

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

  4. Amino acid composition determined using multiple hydrolysis times for three goat milk formulations.

    PubMed

    Rutherfurd, Shane M; Moughan, Paul J; Lowry, Dianne; Prosser, Colin G

    2008-01-01

    The amino acid composition of goat milk formulations with varying protein and carbohydrate concentrations were determined. Proteins in goat milk infant formula, goat milk growing-up formula and goat whole milk powder were hydrolysed using multiple hydrolysis time intervals. A least-squares non-linear regression model was used to predict the free and protein bound amino acid concentrations. The amino acid composition of goat infant formula was compared with human milk reference values. There was good agreement between the multiple hydrolysis and single 24-h hydrolysis methods for approximately one-half of the amino acids. Tryptophan, aspartic acid, threonine, tyrosine, isoleucine, valine, serine and alanine contents were underestimated by 10.6, 5.6, 5.6, 4.7, 4.4, 3.7, 3.7 and 3.6%, respectively, by the single 24-h hydrolysis. The study provides accurate reference data on the amino acid composition of goat milk powders. Goat milk infant formula has amino acids in amounts similar to human milk reference values, when expressed on a per-energy basis.

  5. New insight into the SSC8 genetic determination of fatty acid composition in pigs

    PubMed Central

    2014-01-01

    MAML3 and SETD7 are not the causal mutations for the QTL in the 93 Mb region. However, the results for ELOVL6 support the hypothesis that the ELOVL6:c.-533C > T polymorphism has a pleiotropic effect on backfat and intramuscular fatty acid composition and that it has a role in the determination of the QTL in the 119 Mb region. PMID:24758572

  6. Electrochemical Oxidation and Determination of Oxalic Acid at an Exfoliated Graphite-Polystyrene Composite Electrode

    PubMed Central

    Manea, Florica; Radovan, Ciprian; Corb, Ioana; Pop, Aniela; Burtica, Georgeta; Malchev, Plamen; Picken, Stephen; Schoonman, Joop

    2007-01-01

    An exfoliated graphite-polystyrene composite electrode was evaluated as an alternative electrode in the oxidation and the determination of oxalic acid in 0.1 M Na2SO4 supporting electrolyte. Using CV, LSV, CA procedures, linear dependences I vs. C were obtained in the concentrations range of oxalic acid between 0.5 to 3 mM, with LOD =0.05 mM, and recovery degree of 98%, without need of surface renewing between successive runs. The accuracy of the methods was evaluated as excellent comparing the detection results with that obtained using conventional KMnO4 titration method. In addition, the apparent diffusion coefficient of oxalic acid D was found to be around 2.89 · 10-8 cm2·s-1 by CA and CV.

  7. Lipid nutritional value of legumes: Evaluation of different extraction methods and determination of fatty acid composition.

    PubMed

    Caprioli, Giovanni; Giusti, Federica; Ballini, Roberto; Sagratini, Gianni; Vila-Donat, Pilar; Vittori, Sauro; Fiorini, Dennis

    2016-02-01

    This study sought to contribute to the assessment of the nutritional properties of legumes by determining the fatty acid (FA) composition of 29 legume samples after the evaluation of nine extraction methods. The Folch method and liquid-solid extraction with hexane/isopropanol or with hexane/acetone were investigated, as was the effect of previous hydration of samples. Soxhlet extractions were also evaluated with different solvent mixtures. Results on FA composition using the hexane/isopropanol extraction method were the same in terms of FA composition of the Folch method, but the extraction yield was only around 20-40% of that of the Folch method preceded by hydration. Some types of legumes showed particularly interesting values for the ratio of polyunsaturated fatty acids (PUFAs) n-6/n-3, such as lentils, with the value of 4.0, and Azuki beans, at 3.2. In lentils, the PUFAs% ranged from 42.0% to 57.4%, while in Azuki beans it was 57.5%. PMID:26304436

  8. Identification of Novel Genetic Determinants of Erythrocyte Membrane Fatty Acid Composition among Greenlanders.

    PubMed

    Andersen, Mette Korre; Jørsboe, Emil; Sandholt, Camilla Helene; Grarup, Niels; Jørgensen, Marit Eika; Færgeman, Nils Joakim; Bjerregaard, Peter; Pedersen, Oluf; Moltke, Ida; Hansen, Torben; Albrechtsen, Anders

    2016-06-01

    Fatty acids (FAs) are involved in cellular processes important for normal body function, and perturbation of FA balance has been linked to metabolic disturbances, including type 2 diabetes. An individual's level of FAs is affected by diet, lifestyle, and genetic variation. We aimed to improve the understanding of the mechanisms and pathways involved in regulation of FA tissue levels, by identifying genetic loci associated with inter-individual differences in erythrocyte membrane FA levels. We assessed the levels of 22 FAs in the phospholipid fraction of erythrocyte membranes from 2,626 Greenlanders in relation to single nucleotide polymorphisms genotyped on the MetaboChip or imputed. We identified six independent association signals. Novel loci were identified on chromosomes 5 and 11 showing strongest association with oleic acid (rs76430747 in ACSL6, beta (SE): -0.386% (0.034), p = 1.8x10-28) and docosahexaenoic acid (rs6035106 in DTD1, 0.137% (0.025), p = 6.4x10-8), respectively. For a missense variant (rs80356779) in CPT1A, we identified a number of novel FA associations, the strongest with 11-eicosenoic acid (0.473% (0.035), p = 2.6x10-38), and for variants in FADS2 (rs174570), LPCAT3 (rs2110073), and CERS4 (rs11881630) we replicated known FA associations. Moreover, we observed metabolic implications of the ACSL6 (rs76430747) and CPT1A (rs80356779) variants, which both were associated with altered HbA1c (0.051% (0.013), p = 5.6x10-6 and -0.034% (0.016), p = 3.1x10-4, respectively). The latter variant was also associated with reduced insulin resistance (HOMA-IR, -0.193 (0.050), p = 3.8x10-6), as well as measures of smaller body size, including weight (-2.676 kg (0.523), p = 2.4x10-7), lean mass (-1.200 kg (0.271), p = 1.7x10-6), height (-0.966 cm (0.230), p = 2.0x10-5), and BMI (-0.638 kg/m2 (0.181), p = 2.8x10-4). In conclusion, we have identified novel genetic determinants of FA composition in phospholipids in erythrocyte membranes, and have shown examples of

  9. Identification of Novel Genetic Determinants of Erythrocyte Membrane Fatty Acid Composition among Greenlanders

    PubMed Central

    Sandholt, Camilla Helene; Grarup, Niels; Jørgensen, Marit Eika; Færgeman, Nils Joakim; Bjerregaard, Peter; Pedersen, Oluf; Moltke, Ida; Hansen, Torben; Albrechtsen, Anders

    2016-01-01

    Fatty acids (FAs) are involved in cellular processes important for normal body function, and perturbation of FA balance has been linked to metabolic disturbances, including type 2 diabetes. An individual’s level of FAs is affected by diet, lifestyle, and genetic variation. We aimed to improve the understanding of the mechanisms and pathways involved in regulation of FA tissue levels, by identifying genetic loci associated with inter-individual differences in erythrocyte membrane FA levels. We assessed the levels of 22 FAs in the phospholipid fraction of erythrocyte membranes from 2,626 Greenlanders in relation to single nucleotide polymorphisms genotyped on the MetaboChip or imputed. We identified six independent association signals. Novel loci were identified on chromosomes 5 and 11 showing strongest association with oleic acid (rs76430747 in ACSL6, beta (SE): -0.386% (0.034), p = 1.8x10-28) and docosahexaenoic acid (rs6035106 in DTD1, 0.137% (0.025), p = 6.4x10-8), respectively. For a missense variant (rs80356779) in CPT1A, we identified a number of novel FA associations, the strongest with 11-eicosenoic acid (0.473% (0.035), p = 2.6x10-38), and for variants in FADS2 (rs174570), LPCAT3 (rs2110073), and CERS4 (rs11881630) we replicated known FA associations. Moreover, we observed metabolic implications of the ACSL6 (rs76430747) and CPT1A (rs80356779) variants, which both were associated with altered HbA1c (0.051% (0.013), p = 5.6x10-6 and -0.034% (0.016), p = 3.1x10-4, respectively). The latter variant was also associated with reduced insulin resistance (HOMA-IR, -0.193 (0.050), p = 3.8x10-6), as well as measures of smaller body size, including weight (-2.676 kg (0.523), p = 2.4x10-7), lean mass (-1.200 kg (0.271), p = 1.7x10-6), height (-0.966 cm (0.230), p = 2.0x10-5), and BMI (-0.638 kg/m2 (0.181), p = 2.8x10-4). In conclusion, we have identified novel genetic determinants of FA composition in phospholipids in erythrocyte membranes, and have shown examples of

  10. Au nanoparticles/poly(caffeic acid) composite modified glassy carbon electrode for voltammetric determination of acetaminophen.

    PubMed

    Li, Tianbao; Xu, Juan; Zhao, Lei; Shen, Shaofei; Yuan, Maosen; Liu, Wenming; Tu, Qin; Yu, Ruijin; Wang, Jinyi

    2016-10-01

    An Au nanoparticles/poly(caffeic acid) (AuNPs/PCA) composite modified glassy carbon (GC) electrode was prepared by successively potentiostatic technique in pH 7.4 phosphate buffer solution containing 0.02mM caffeic acid and 1.0mM HAuCl4. Electrochemical characterization of the AuNPs/PCA-GC electrode was investigated by electrochemical impedance spectroscopy and cyclic voltammetry. The electrochemical behavior of acetaminophen (AP) at the AuNPs/PCA-GC electrode was also studied by cyclic voltammetry. Compared with bare GC and poly(caffeic acid) modified GC electrode, the AuNPs/PCA-GC electrode was exhibited excellent electrocatalytic activity toward the oxidation of AP. The plot of catalytic current versus AP concentration showed two linear segments in the concentration ranges 0.2-20µM and 50-1000µM. The detection limit of 14 nM was obtained by using the first range of the calibration plot. The AuNPs/PCA-GC electrode has been successfully applied and validated by analyzing AP in blood, urine and pharmaceutical samples. PMID:27474318

  11. Au nanoparticles/poly(caffeic acid) composite modified glassy carbon electrode for voltammetric determination of acetaminophen.

    PubMed

    Li, Tianbao; Xu, Juan; Zhao, Lei; Shen, Shaofei; Yuan, Maosen; Liu, Wenming; Tu, Qin; Yu, Ruijin; Wang, Jinyi

    2016-10-01

    An Au nanoparticles/poly(caffeic acid) (AuNPs/PCA) composite modified glassy carbon (GC) electrode was prepared by successively potentiostatic technique in pH 7.4 phosphate buffer solution containing 0.02mM caffeic acid and 1.0mM HAuCl4. Electrochemical characterization of the AuNPs/PCA-GC electrode was investigated by electrochemical impedance spectroscopy and cyclic voltammetry. The electrochemical behavior of acetaminophen (AP) at the AuNPs/PCA-GC electrode was also studied by cyclic voltammetry. Compared with bare GC and poly(caffeic acid) modified GC electrode, the AuNPs/PCA-GC electrode was exhibited excellent electrocatalytic activity toward the oxidation of AP. The plot of catalytic current versus AP concentration showed two linear segments in the concentration ranges 0.2-20µM and 50-1000µM. The detection limit of 14 nM was obtained by using the first range of the calibration plot. The AuNPs/PCA-GC electrode has been successfully applied and validated by analyzing AP in blood, urine and pharmaceutical samples.

  12. Quantitative determination of fatty acid compositions in micro-encapsulated fish-oil supplements using Fourier transform infrared (FTIR) spectroscopy.

    PubMed

    Vongsvivut, Jitraporn; Heraud, Philip; Zhang, Wei; Kralovec, Jaroslav A; McNaughton, Don; Barrow, Colin J

    2012-11-15

    The research describes a rapid method for the determination of fatty acid (FA) contents in a micro-encapsulated fish-oil (μEFO) supplement by using attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopic technique and partial least square regression (PLSR) analysis. Using the ATR-FTIR technique, the μEFO powder samples can be directly analysed without any pre-treatment required, and our developed PLSR strategic approach based on the acquired spectral data led to production of a good linear calibration with R(2)=0.99. In addition, the subsequent predictions acquired from an independent validation set for the target FA compositions (i.e., total oil, total omega-3 fatty acids, EPA and DHA) were highly accurate when compared to the actual values obtained from standard GC-based technique, with plots between predicted versus actual values resulting in excellent linear fitting (R(2)≥0.96) in all cases. The study therefore demonstrated not only the substantial advantage of the ATR-FTIR technique in terms of rapidness and cost effectiveness, but also its potential application as a rapid, potentially automated, online monitoring technique for the routine analysis of FA composition in industrial processes when used together with the multivariate data analysis modelling.

  13. Automated determination of fatty acid methyl ester and cis/trans methyl ester composition of fats and oils.

    PubMed

    de Koning, S; van der Meer, B; Alkema, G; Janssen, H G; Brinkman, U A

    2001-07-13

    The determination of the fatty acid composition (as methyl esters, FAMEs) of fats and oils and their cis/trans (CTME) distribution requires a simple, but manual and time-consuming sample preparation. The so-called BF3 method is often the preferred procedure. Because FAME/CTME analyses are encountered very frequently in the food industry, an automated, robot-based alternative is proposed which uses the sodium methylate procedure. After sample weighing and the (manual) addition of heptane (2 min), a XYZ robotic autosampler is used for all remaining work, which includes reagent addition, agitation, sample settling and the final injection into the gas chromatograph (10 min). The performance of the sodium methylate and BF3 methods are compared by analysing some 30 oil and fat samples. The novel procedure is much faster (less than 15 min versus ca. 1 h) and manual sample handling is drastically decreased. The experimental results obtained with the two methods frequently are the same, while small differences can be explained by (known) differences of the two methods in the conversion of minor oil/fat constituents, such as free fatty acids, wax esters and sterol esters. In case of FAME analyses, a hot injection is to be preferred over a cold injection. The RSDs of the peak areas were 1.5% for the major fatty acids to 11% for peaks that were just above the noise level. The detection limit were approximately 0.03%.

  14. Well acidizing compositions and methods

    SciTech Connect

    Swanson, B. L.

    1980-12-23

    Gelled acidic compositions suitable for matrix acidizing or fracture acidizing of subterranean formations are provided comprising water, a water-dispersible polymeric viscosifier such as a polymer of acrylamide, an acid, and a polyphenolic material such as lignite.

  15. Sex, but not maternal protein or folic acid intake, determines the fatty acid composition of hepatic phospholipids, but not of triacylglycerol, in adult rats.

    PubMed

    Burdge, G C; Slater-Jefferies, J L; Grant, R A; Chung, W-S; West, A L; Lillycrop, K A; Hanson, M A; Calder, P C

    2008-01-01

    The aim of the study was to investigate whether the protein and folic acid content of the maternal diet and the sex of the offspring alter the polyunsaturated fatty acid content of hepatic phospholipids and triacylglycerol (TAG). Pregnant rats were fed diets containing 18% or 9% protein with either 1 or 5mg/kg folic acid. Maternal diet did not alter hepatic lipid composition in the adult offspring. Data from each maternal dietary group were combined and reanalysed. The proportion of 18:0, 20:4n-6 and 22:6n-3 in liver phospholipids was higher in females than in males, while hepatic TAG composition did not differ between sexes. Delta5 Desaturase expression was higher in females than in males. Neither Delta5 nor Delta6 desaturase expression was related to polyunsaturated fatty acid concentrations. These results suggest that sex differences in liver phospholipid fatty acid composition may reflect primary differences in the specificity of phospholipid biosynthesis.

  16. Selective and sensitive determination of uric acid in the presence of ascorbic acid and dopamine by PDDA functionalized graphene/graphite composite electrode.

    PubMed

    Yu, Yanyan; Chen, Zuanguang; Zhang, Beibei; Li, Xinchun; Pan, Jianbin

    2013-08-15

    In this work, a facile electrochemical sensor based on poly(diallyldimethylammonium chloride) (PDDA) functionalized graphene (PDDA-G) and graphite was fabricated. The composite electrode exhibited excellent selectivity and sensitivity towards uric acid (UA), owing to the electrocatalytic effect of graphene nanosheets and the electrostatic attractions between PDDA-G and UA. The anodic peak current of UA obtained by cyclic voltammetry (CV) increased over 10-fold compared with bare carbon paste electrode (CPE). And the reversibility of the oxidation process was improved significantly. Differential pulse voltammetry (DPV) was used to determine UA in the presence of ascorbic acid (AA) and dopamine (DA). It was found that all of oxidation peaks of three species could be well resolved, and the peak current of UA was much stronger than the other two components. More importantly, considerable-amount of AA and DA showed negligible interference to UA assay. The calibration curve for UA ranged from 0.5 to 20 μmol L(-1) with a correlation coefficient of 0.9934. The constructed sensor has been employed to quantitatively determine UA in urine samples.

  17. Parenteral lipid fatty acid composition directly determines the fatty acid composition of red blood cell and brain lipids in preterm pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Studies in enterally-fed infants have shown a positive effect of n-3 long-chain polyunsaturated fatty acid (LCPUFA) supplementatin on neurodevelopment. The effect of n-3 LCPUFA in fish oil-based parenteral (PN) lipid emulsions on neuronal tissues of PN-fed preterm infants is unknown. The objective ...

  18. Determination of essential fatty acid composition among mutant lines of Canola (Brassica napus), through high pressure liquid chromatography.

    PubMed

    Raza, Ghulam; Siddique, Aquil; Khan, Imtiaz Ahmad; Ashraf, Muhammed Yasin; Khatri, Abdullah

    2009-12-01

    The present study aimed to quantify the methyl esters of lenoleic acid (LA), gamma-lenolenic acid (LNA) and oleic acid (OL) in the oil of Brassica napus mutants. Five stable mutants (ROO-75/1, ROO-100/6, ROO-125/12, ROO-125/14, and ROO-125/17) of B. napus cv. 'Rainbow' (P) and three mutants (W97-95/16, W97-0.75/11 and W97-.075/13) of B. napus cv. 'Westar' (P) at M6 stage, exhibiting better yield and yield components, were analyzed for essential fatty acids. The highest seed yield was observed in the mutant (ROO-100/6) followed by ROO-125/14 of Rainbow, that is, 34% and 32% higher than their parent plants, respectively. Westar mutant W97-75/11 also showed 30% higher seed yield than its parent plant. High performance liquid chromatography analysis of the composition of fatty acids indicated that OL was the most dominant fatty acid, ranging from 39.1 to 66.3%; LA was second (15.3-41.6%) and LNA was third (18.1-28.9%). Mutant ROO-125/14 showed higher OL contents than parent (Rainbow). These results are expected to support the approval of ROO-125/14 in the National Uniform Varietal Yield Trials (NUVYT) as a new variety based on high oil quality.

  19. Quantitative determination of fatty acid chain composition in pork meat products by high resolution 1H NMR spectroscopy.

    PubMed

    Siciliano, Carlo; Belsito, Emilia; De Marco, Rosaria; Di Gioia, Maria Luisa; Leggio, Antonella; Liguori, Angelo

    2013-01-15

    High resolution (1)H NMR spectroscopy was proposed for the determination of the fatty acid chain profile of lipids in pork meat products during ripening. Two typical Mediterranean PDO salami produced in Calabria, a region in the Southern Italy, were chosen as a case of study. Quantitative NMR analysis provided the fatty acid chain profiles of total lipid extracts. The transesterification of total lipid extracts furnished FAME mixtures that enabled quantitation of fatty acid acyl chains in the acylglycerol and FFA portions. In all cases, oleyl chains were predominant, and high amounts of polyunsaturated fatty acid chains were observed. The proposed spectroscopic method allowed also the estimation of the most important nutritional parameters of dry fermented meat products.

  20. Square-wave stripping voltammetric determination of caffeic acid on electrochemically reduced graphene oxide-Nafion composite film.

    PubMed

    Filik, Hayati; Çetintaş, Gamze; Avan, Asiye Aslıhan; Aydar, Sevda; Koç, Serkan Naci; Boz, İsmail

    2013-11-15

    An electrochemical sensor composed of Nafion-graphene nanocomposite film for the voltammetric determination of caffeic acid (CA) was studied. A Nafion graphene oxide-modified glassy carbon electrode was fabricated by a simple drop-casting method and then graphene oxide was electrochemically reduced over the glassy carbon electrode. The electrochemical analysis method was based on the adsorption of caffeic acid on Nafion/ER-GO/GCE and then the oxidation of CA during the stripping step. The resulting electrode showed an excellent electrocatalytical response to the oxidation of caffeic acid (CA). The electrochemistry of caffeic acid on Nafion/ER-GO modified glassy carbon electrodes (GCEs) were studied by cyclic voltammetry and square-wave adsorption stripping voltammetry (SW-AdSV). At optimized test conditions, the calibration curve for CA showed two linear segments: the first linear segment increased from 0.1 to 1.5 and second linear segment increased up to 10 µM. The detection limit was determined as 9.1×10(-8) mol L(-1) using SW-AdSV. Finally, the proposed method was successfully used to determine CA in white wine samples.

  1. Au-Pd/reduced graphene oxide composite as a new sensing layer for electrochemical determination of ascorbic acid, acetaminophen and tyrosine.

    PubMed

    Tadayon, Fariba; Vahed, Saba; Bagheri, Hasan

    2016-11-01

    An Au-Pd/reduced graphene oxide composite was employed as a novel electrode material for the sensitive and simultaneous determination of ascorbic acid, acetaminophen and tyrosine. The electrochemical response characteristics of the modified electrode toward the analytes were investigated by differential pulse voltammetry and cyclic voltammetry. The responses of the electrochemical sensor for the target analytes were found to be improved significantly in comparison with those obtained using a conventional carbon paste electrode (CPE) and reduced graphene oxide/CPE. The experimental conditions for simultaneous determination of these species have been established. Ternary mixtures of analytes can be determined in the ranges of 0.03-9.50μM. Under optimal conditions, the limits of detection were 15.7, 7.6 and 11.1nM for ascorbic acid, acetaminophen, and tyrosine, respectively. The method was applied successfully to determine the analytes in urine, serum and pharmaceutical samples simultaneously. PMID:27524083

  2. Nucleic acid detection compositions

    DOEpatents

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

    2008-08-05

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

  3. Amino acid composition of some Mexican foods.

    PubMed

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

    2005-06-01

    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.

  4. Body composition, dietary carbohydrates and fatty acids determine post-fertilisation development of bovine oocytes in vitro.

    PubMed

    Adamiak, S J; Powell, K; Rooke, J A; Webb, R; Sinclair, K D

    2006-02-01

    This study assessed the interactive effects of carbohydrate type (fibre vs starch) and fatty acid (FA) supplementation (0% vs 6% calcium soaps of palm oil FA) on the post-fertilisation development of oocytes recovered from low and moderate body condition score (BCS) heifers. A secondary objective was to compare the FA composition of plasma to that of granulosa cells (GCs) and cumulus-oocyte complexes (COCs) from these animals, and to relate these findings to the developmental potential of oocytes. Plasma, GCs and COCs were recovered from 32 heifers on day 5 of a synchronised oestrous cycle for FA analyses. Oocytes were also recovered on days 10 and 15 of the same cycle after short-term ovarian stimulation (FSH + GnRH), and matured, fertilised and cultured to the blastocyst stage in vitro. High levels of dietary starch increased (P < 0.01) plasma insulin but, together with dietary FA, reduced (P < 0.05) blastocyst yields in low, but not in moderate, BCS heifers. Diet-induced alterations to the FA content of plasma were less apparent in GCs and COCs. In summary, although dietary lipids increased the FA content of COCs, the selective uptake of saturated FAs at the expense of mainly polyunsaturated FAs within the follicular compartment ensured that the FA composition of COCs was largely unaffected by diet. However, the concentration of saturated FAs within COCs was inherently high, and so further increases in FA content may have impaired post-fertilisation development. The data establish a robust nutritional framework for more detailed studies into the mechanistic effects of dietary composition on the post-fertilisation developmental potential of oocytes. PMID:16452718

  5. Mammalian evolution: timing and implications from using the LogDeterminant transform for proteins of differing amino acid composition.

    PubMed

    Penny, D; Hasegawa, M; Waddell, P J; Hendy, M D

    1999-03-01

    We explore the tree of mammalian mtDNA sequences, using particularly the LogDet transform on amino acid sequences, the distance Hadamard transform, and the Closest Tree selection criterion. The amino acid composition of different species show significant differences, even within mammals. After compensating for these differences, nearest-neighbor bootstrap results suggest that the tree is locally stable, though a few groups show slightly greater rearrangements when a large proportion of the constant sites are removed. Many parts of the trees we obtain agree with those on published protein ML trees. Interesting results include a preference for rodent monophyly. The detection of a few alternative signals to those on the optimal tree were obtained using the distance Hadamard transform (with results expressed as a Lento plot). One rearrangement suggested was the interchange of the position of primates and rodents on the optimal tree. The basic stability of the tree, combined with two calibration points (whale/cow and horse/rhinoceros), together with a distant secondary calibration from the mammal/bird divergence, allows inferences of the times of divergence of putative clades. Allowing for sampling variances due to finite sequence length, most major divergences amongst lineages leading to modern orders, appear to occur well before the Cretaceous/Tertiary (K/T) boundary. Implications arising from these early divergences are discussed, particularly the possibility of competition between the small dinosaurs and the new mammal clades. PMID:12078647

  6. Determination of the fatty acid composition of saponified vegetable oils using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

    PubMed

    Ayorinde, F O; Garvin, K; Saeed, K

    2000-01-01

    A method using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) for the determination of the fatty acid composition of vegetable oils is described and illustrated with the analysis of palm kernel oil, palm oil, olive oil, canola oil, soybean oil, vernonia oil, and castor oil. Solutions of the saponified oils, mixed with the matrix, meso-tetrakis(pentafluorophenyl)porphyrin, provided reproducible MALDI-TOF spectra in which the ions were dominated by sodiated sodium carboxylates [RCOONa + Na]+. Thus, palm kernel oil was found to contain capric acid, lauric acid, myristic acid, palmitic acid, oleic acid, and stearic acid. Palm oil had a fatty acid profile including palmitic, linoleic, oleic, and stearic. The relative percentages of the fatty acids in olive oil were palmitoleic (1.2 +/- 0.5), palmitic (10.9 +/- 0.8), linoleic (0.6 +/- 0.1), linoleic (16.5 +/- 0.8), and oleic (70.5 +/- 1.2). For soybean oil, the relative percentages were: palmitoleic (0.4 +/- 0.4), palmitic (6.0 +/- 1.3), linolenic (14.5 +/- 1.8), linoleic (50.1 +/- 4.0), oleic (26.1 +/- 1.2), and stearic (2.2 +/- 0.7). This method was also applied to the analysis of two commercial soap formulations. The first soap gave a fatty acid profile that included: lauric (19.4% +/- 0.8), myristic (9.6% +/- 0.5), palmitoleic (1.9% +/- 0.3), palmitic (16.3% +/- 0.9), linoleic (5.6% +/- 0.4), oleic (37.1% +/- 0.8), and stearic (10.1% +/- 0.7) and that of the second soap was: lauric (9.3% +/- 0.3), myristic (3.8% +/- 0.5), palmitoleic (3.1% +/- 0.8), palmitic (19.4% +/- 0.8), linoleic (4.9% +/- 0.7), oleic (49.5% +/- 1.1), and stearic (10.0% +/- 0.9). The MALDI-TOFMS method described in this communication is simpler and less time-consuming than the established transesterification method that is coupled with analysis by gas chromatography/mass spectrometry (GC/MS). The new method could be used routinely to determine the qualitative fatty acid composition of vegetable oils

  7. Determination of molecular species composition of C80 or longer-chain alpha-mycolic acids in Mycobacterium spp. by gas chromatography-mass spectrometry and mass chromatography.

    PubMed

    Kaneda, K; Naito, S; Imaizumi, S; Yano, I; Mizuno, S; Tomiyasu, I; Baba, T; Kusunose, E; Kusunose, M

    1986-12-01

    The molecular species composition of alpha-mycolic acids ranging from C68 to C86 in 13 rapidly growing and 12 slowly growing mycobacterial species was determined by gas chromatography, gas chromatography-mass spectrometry, and mass chromatography. In gas chromatographic analysis, the molecular species of alpha-mycolic acids were well separated as trimethylsilyl ether derivatives of the methyl esters, according to their total carbon numbers. The total carbon and double-bond numbers of mycolic acids at each peak on gas chromatograms were determined from the [M]+, [M - 15]+, and [M - 90]+ ions on the mass spectrum, and straight and branched chain structures were identified by the mass fragment ions [A]+, due to C2--C3 cleavage [R-CH-O-Si(CH3)3]+, and [B]+, due to C3--C4 cleavage [(CH3)3-Si-O-CH-CH(R')-COOCH3]+. The concentration of odd- and even-carbon-numbered mycolic acids, which often overlap each other on gas chromatograms, and the composition of three homologous mycolic acids with different alpha units (C22:0, C24:0, and C26:0) were clearly determined by mass chromatography monitoring [M - 15]+ ions and [B - 29]+ ions, respectively. The molecular species composition of alpha-mycolic acids and their average carbon numbers (av. cn.) as a simple expression of the composition were calculated from the mass chromatograms. Each mycobacterial species examined was demonstrated to possess a characteristic profile of alpha-mycolic acid composition, and based on this the species were classified approximately into eight groups: C68 to C76 (av. cn. 72), dienoic, possessing a C20 alkyl branch at the 2 position (C22 alpha-unit) for Mycobacterium diernhoferi and Mycobacterium sp. strain 3707, a chromogenic rapid grower; C72 to C78 (av. cn. 75), dienoic with both C22 and C24 alpha units, containing a small or a large amount of odd-carbon-numbered molecules, for M. vaccae, M. rhodesiae, and M. phlei (chromogenic rapid growers); C72 to C80 (av. cn. 75 to 77), dienoic with C24 alpha

  8. Composition for nucleic acid sequencing

    SciTech Connect

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

    2008-08-26

    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.

  9. Electrochemical behavior and voltammetric determination of acetaminophen based on glassy carbon electrodes modified with poly(4-aminobenzoic acid)/electrochemically reduced graphene oxide composite films.

    PubMed

    Zhu, Wencai; Huang, Hui; Gao, Xiaochun; Ma, Houyi

    2014-12-01

    Poly(4-aminobenzoic acid)/electrochemically reduced graphene oxide composite film modified glassy carbon electrodes (4-ABA/ERGO/GCEs) were fabricated by a two-step electrochemical method. The electrochemical behavior of acetaminophen at the modified electrode was investigated by means of cyclic voltammetry. The results indicated that 4-ABA/ERGO composite films possessed excellent electrocatalytic activity towards the oxidation of acetaminophen. The electrochemical reaction of acetaminophen at 4-ABA/ERGO/GCE is proved to be a surface-controlled process involving the same number of protons and electrons. The voltammetric determination of acetaminophen performed with the 4-ABA/ERGO modified electrode presents a good linearity in the range of 0.1-65 μM with a low detection limit of 0.01 μM (S/N=3). In the case of using the 4-ABA/ERGO/GCE, acetaminophen and dopamine can be simultaneously determined without mutual interference. Furthermore, the 4-ABA/ERGO/GCE has good reproducibility and stability, and can be used to determine acetaminophen in tablets.

  10. Fabrication of electrochemical interface based on boronic acid-modified pyrroloquinoline quinine/reduced graphene oxide composites for voltammetric determination of glycated hemoglobin.

    PubMed

    Zhou, Yanli; Dong, Hui; Liu, Lantao; Hao, Yuanqiang; Chang, Zhu; Xu, Maotian

    2015-02-15

    A voltammetric sensor for determination of glycated hemoglobin (HbA1c) was developed based on the composites of phenylboronic acid-modified pyrroloquinoline quinine (PBA-PQQ) and reduced graphene oxide. After the electrodeposition of reduced graphene oxide (ERGO) on the glassy carbon (GC) electrode, PQQ multilayer was decorated on the surface of the ERGO/GC electrode via potential cycling. Further modification with PBA would lead to the formation of the working electrode, namely PBA-PQQ/ERGO/GC electrode. PQQ on the electrode exhibited a quasi-reversible electrode process with 2-electron transfer and 2-proton participation, and the electron transfer efficiency was further enhanced by the introduction of ERGO layer. The complexation of PBA with HbA1c through specific boronic acid-diol recognition could cause the change of the oxidation peak current of PQQ on the electrode, which was utilized for HbA1c detection. Under the optimized conditions, the PBA-PQQ/ERGO/GC electrode provided high selectivity and high sensitivity for HbA1c detection with a linear range of 9.4-65.8 μg mL(-1) and a low detection limit of 1.25 μg mL(-1). The fabricated sensor was also successfully applied to determine the percentages of HbA1c in whole blood of healthy individuals.

  11. Cellular fatty acid composition of Haemophilus equigenitalis.

    PubMed Central

    Sugimoto, C; Miyagawa, E; Mitani, K; Nakazawa, M; Isayama, Y

    1982-01-01

    The cellular fatty acid composition of eight Haemophilus equigenitalis strains was determined by gas-liquid chromatography. All strains showed a grossly similar pattern characterized by large amounts of 18:1 and 16:0. The amounts of 16:1, 18:2, 18:0, 3-OH 14:0, 3-OH 16:0, and 3-OH 18:1 were relatively small. PMID:7096556

  12. Well acidizing compositions and method

    SciTech Connect

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

    1991-07-23

    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.

  13. Adequacy of the Measurement Capability of Fatty Acid Compositions and Sterol Profiles to Determine Authenticity of Milk Fat Through Formulation of Adulterated Butter.

    PubMed

    Soha, Sahel; Mortazavian, Amir M; Piravi-Vanak, Zahra; Mohammadifar, Mohammad A; Sahafar, Hamed; Nanvazadeh, Sara

    2015-01-01

    In this research a comparison has been made between the fatty acid and sterol compositions of Iranian pure butter and three samples of adulterated butter. These samples were formulated using edible vegetable fats/oils with similar milk fat structures including palm olein, palm kernel and coconut oil to determine the authenticity of milk fat. The amount of vegetable fats/oils used in the formulation of the adulterated butter was 10%. The adulterated samples were formulated so that their fatty acid profiles were comforted with acceptable levels of pure butter as specified by the Iranian national standard. Based on the type of the vegetable oil/fat, fatty acids such as C4:0, C12:0 and C18:2 were used as indicators for the adulterated formulations. According to the standard method of ISO, the analysis was performed using gas chromatography. The cholesterol contents were 99.71% in pure butter (B1), and 97.61%, 98.48% and 97.98% of the total sterols in the samples adulterated with palm olein, palm kernel and coconut oil (B2, B3 and B4), respectively. Contents of the main phytosterol profiles such as β-sitosterol, stigmasterol and campesterol were also determined. The β-sitosterol content, as an indicator of phytosterols, was 0% in pure butter, and 1.81%, 1.67% and 2.16%, of the total sterols in the adulterated samples (B2, B3 and B4), respectively. Our findings indicate that fatty acid profiles are not an efficient indicator for butter authentication. Despite the increase in phytosterols and the reduction in cholesterol and with regard to the conformity of the sterol profiles of the edible fats/oils used in the formulations with Codex standards, lower cholesterol and higher phytosterols contents should have been observed. It can therefore be concluded that sterol measurement is insufficient to verify the authenticity of the milk fat in butter. It can therefore be concluded that sterol measurement is insufficient in verifying the authenticity of milk fat.

  14. Adequacy of the Measurement Capability of Fatty Acid Compositions and Sterol Profiles to Determine Authenticity of Milk Fat Through Formulation of Adulterated Butter.

    PubMed

    Soha, Sahel; Mortazavian, Amir M; Piravi-Vanak, Zahra; Mohammadifar, Mohammad A; Sahafar, Hamed; Nanvazadeh, Sara

    2015-01-01

    In this research a comparison has been made between the fatty acid and sterol compositions of Iranian pure butter and three samples of adulterated butter. These samples were formulated using edible vegetable fats/oils with similar milk fat structures including palm olein, palm kernel and coconut oil to determine the authenticity of milk fat. The amount of vegetable fats/oils used in the formulation of the adulterated butter was 10%. The adulterated samples were formulated so that their fatty acid profiles were comforted with acceptable levels of pure butter as specified by the Iranian national standard. Based on the type of the vegetable oil/fat, fatty acids such as C4:0, C12:0 and C18:2 were used as indicators for the adulterated formulations. According to the standard method of ISO, the analysis was performed using gas chromatography. The cholesterol contents were 99.71% in pure butter (B1), and 97.61%, 98.48% and 97.98% of the total sterols in the samples adulterated with palm olein, palm kernel and coconut oil (B2, B3 and B4), respectively. Contents of the main phytosterol profiles such as β-sitosterol, stigmasterol and campesterol were also determined. The β-sitosterol content, as an indicator of phytosterols, was 0% in pure butter, and 1.81%, 1.67% and 2.16%, of the total sterols in the adulterated samples (B2, B3 and B4), respectively. Our findings indicate that fatty acid profiles are not an efficient indicator for butter authentication. Despite the increase in phytosterols and the reduction in cholesterol and with regard to the conformity of the sterol profiles of the edible fats/oils used in the formulations with Codex standards, lower cholesterol and higher phytosterols contents should have been observed. It can therefore be concluded that sterol measurement is insufficient to verify the authenticity of the milk fat in butter. It can therefore be concluded that sterol measurement is insufficient in verifying the authenticity of milk fat. PMID:26246145

  15. Gelled acidic well treating composition and process

    SciTech Connect

    Swanson, B.L.

    1981-01-13

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

  16. Fatty acid composition of water buffalo meat.

    PubMed

    Sharma, N; Gandemer, G; Goutefongea, R; Kowale, B N

    1986-01-01

    The fatty acid composition of intramuscular lipids of Longissimus dorsi (LD), Psoas major (PM), Biceps femoris (BF), Semitendinosus (ST) muscles and liver of water buffalo male calves was determined by capillary gas-liquid chromatography. The content of total lipids in the LD muscle was found to be maximum, followed by PM, BF and ST in decreasing order (1·03, 0·99, 0·66 and 0·55g/100g of fresh muscle). Liver contained 2·65 g of total lipids per 100 g of fresh tissue. Following the anatomical location, intramuscular lipids contained 44-55% of saturated fatty acids, of which the major components were stearic and palmitic acids. Mono-unsaturated fatty acids (31-40%) composed mainly oleic acid (90%). The PUFA contents in PM, LD, ST and BF were, respectively, 11%, 12%, 13% and 16%. The predominant PUFA were linoleic (66%) and arachidonic (25%). The significance of difference of PUFA content between muscles is discussed. Liver contained 48%, 27% and 22% saturated, monosaturated and PUFA, respectively. The PUFA in liver were linoleic (36%), C20 (47%) and C22 (9%).

  17. Effect of temperature and solvent composition on acid dissociation equilibria, I: Sequenced (s)(s)pKa determination of compounds commonly used as buffers in high performance liquid chromatography coupled to mass spectroscopy detection.

    PubMed

    Padró, Juan M; Acquaviva, Agustín; Tascon, Marcos; Gagliardi, Leonardo G; Castells, Cecilia B

    2012-05-01

    A new automated and rapid potentiometric method for determining the effect of organic-solvent composition on pK(a) has been developed. It is based on the measurements of pH values of buffer solutions of variable solvent compositions using a combined glass electrode. Additions of small volumes of one precisely thermostated solution into another, both containing exactly the same analytical concentrations of the buffer components, can produce continuous changes in the solvent composition. Two sequences of potential measurements, one of increasing and the other of decreasing solvent content, are sufficient to obtain the pK(a) values of the acidic compound within the complete solvent-composition range in about 2h. The experimental design, procedures, and calculations needed to convert the measured pH into the thermodynamic pK(a) values are thoroughly discussed. This rapid and automated method allows the systematic study of the effect of solvent compositions and temperatures on the pK(a). It has been applied to study the dissociation constants of two monoprotic acids: formic acid and triethylamine:HCl in acetonitrile/water mixtures within the range from 0 to 90% (v/v) at temperatures between 20°C and 60°C. These volatile compounds are frequently used to control the pH of the mobile phase in HPLC, especially in methods coupled to mass-spectrometry detection. The obtained pK(a) values are in excellent agreement with those previously reported. The results were fitted to empirical functions between pK(a) and temperature and composition. These equations, which can be used to estimate the pK(a) of these substances at any composition and temperature, would be highly useful in practical work during chromatographic method development.

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

    PubMed

    Lee, H S; Wrolstad, R E

    1988-01-01

    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.

  19. Starch composites with aconitic acid.

    PubMed

    Gilfillan, William Neil; Doherty, William O S

    2016-05-01

    The aim of this project is to examine the effectiveness of using aconitic acid (AcA), a tricarboxylic acid which contains a carbon/carbon double bond (CC), to enhance the properties of starch-based films. Starch/glycerol cast films were prepared with 0, 2, 5, 10 and 15wt% AcA (starch wt% basis) and the properties analysed. It was shown that AcA acted as both a cross-linking agent and also a strong plasticising agent. The 5wt% AcA derived starch films were the most effectively cross-linked having the lowest solubility (28wt%) and decreased swelling coefficient (35vol.%) by approximately 3 times and 2.4 times respectively compared to the control film submerged in water (23°C). There was also a significant increase in the film elongation at break by approximately 35 times (compared to the control) with the addition of 15wt% AcA, emphasising the plasticising effect of AcA. However, generally there was a reduced tensile strength, softening of the film, and reduced thermal stability with increased amounts of AcA. PMID:26876996

  20. Seed oil and fatty acid composition in Capsicum spp

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The oil content and fatty acid composition of seed of 233 genebank accessions (total) of nine Capsicum species, and a single accession of Tubocapsicum anomalum, were determined. The physicochemical characteristics of oil extracted from seed of C. annuum and C. baccatum were also examined. Significan...

  1. Analysis of fatty acid content and composition in microalgae.

    PubMed

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

    2013-01-01

    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 (ω-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

  2. Proximate composition, amino acid and fatty acid composition of fish maws.

    PubMed

    Wen, Jing; Zeng, Ling; Xu, Youhou; Sun, Yulin; Chen, Ziming; Fan, Sigang

    2016-01-01

    Fish maws are commonly recommended and consumed in Asia over many centuries because it is believed to have some traditional medical properties. This study highlights and provides new information on the proximate composition, amino acid and fatty acid composition of fish maws of Cynoscion acoupa, Congresox talabonoides and Sciades proops. The results indicated that fish maws were excellent protein sources and low in fat content. The proteins in fish maws were rich in functional amino acids (FAAs) and the ratio of FAAs and total amino acids in fish maws ranged from 0.68 to 0.69. Among species, croaker C. acoupa contained the most polyunsaturated fatty acids, arachidonic acid, docosahexaenoic acid and eicosapntemacnioc acid, showing the lowest value of index of atherogenicity and index of thrombogenicity, showing the highest value of hypocholesterolemic/hypercholesterolemic ratio, which is the most desirable.

  3. Comparative fatty acid composition of four Sargassum species (Fucales, Phaeophyta)

    NASA Astrophysics Data System (ADS)

    Wu, Xiang-Chun; Lu, Bao-Ren; Tseng, C. K.

    1995-12-01

    Fatty acid composition of four Sargassum species from Qingdao and Shidao, Shandong Province was investigated. 16:0 (palmitic acid) was the major saturated fatty acid. C18 and C20 were the main polyunsaturated fatty acids (PUFAs). Arachidonic acid and eicosapentaenoic acid predominated among polyenoic acids in all the algal species examined, except for Sargassum sp. which had low concentration of eicosapentaenoic acid.

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

    PubMed Central

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

    2013-01-01

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

  5. Determination of isotopic composition of dissolved copper in seawater by multi-collector inductively coupled plasma mass spectrometry after pre-concentration using an ethylenediaminetriacetic acid chelating resin.

    PubMed

    Takano, Shotaro; Tanimizu, Masaharu; Hirata, Takafumi; Sohrin, Yoshiki

    2013-06-19

    Copper is an essential trace metal that shows a vertical recycled-scavenged profile in the ocean. To help elucidate the biogeochemical cycling of Cu in the present and past oceans, it is important to determine the distribution of Cu isotopes in seawater. However, precise isotopic analysis of Cu has been impaired by the low concentrations of Cu as well as co-existing elements that interfere with measurements by multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS). The objective of this study is to develop a simple Cu pre-concentration method using Nobias-chelate PA1 resin (Hitachi High Technologies). This extraction followed by anion exchange, allows precise analysis of the Cu isotopic composition in seawater. Using this method, Cu was quantitatively concentrated from seawater and >99.9999% of the alkali and alkaline earth metals were removed. The technique has a low procedural blank of 0.70 ng for Cu for a 2L sample and the precision of the Cu isotopic analysis was ±0.07‰ (±2SD, n=6). We applied this method to seawater reference materials (i.e., CASS-5 and NASS-6) and seawater samples obtained from the northwestern Pacific Ocean. The range of dissolved δ(65)Cu was 0.40-0.68‰.

  6. Infant cerebral cortex phospholipid fatty-acid composition and diet.

    PubMed

    Farquharson, J; Cockburn, F; Patrick, W A; Jamieson, E C; Logan, R W

    1992-10-01

    It has not been established whether nutrition in early infancy affects subsequent neurodevelopment and function. If there is an effect, it seems probable that the essential fatty acids and their metabolites, the major constituents of brain structure, will be the most susceptible to dietary influence. We determined the phospholipid fatty-acid composition of cerebral cortex grey matter obtained from 20 term and 2 preterm infants who had died of "cot deaths" and related results to the milk diet the infants had received. Tissues were analysed by gas chromatography. The mean weight percentage of docosahexaenoic acid was significantly greater (p less than 0.02) in 5 breast-milk-fed infants (9.7%) than in 5 age-comparable formula-milk-fed infants (7.6%). In these formula-fed babies, the overall percentage of long-chain polyunsaturated fatty acids was maintained by increased incorporation of the major n-6 series fatty acids. In 1 formula-fed preterm infant, in whom the lowest concentration of cortical docosahexaenoic acid was found, the compensatory effect was only partial with both n-9 series eicosatrienoic acid or Mead acid and docosatrienoic acid also detected in the phospholipid. Supplementation of formula milks for term infants with docosahexaenoic acid and those for preterm infants with both docosahexaenoic and arachidonic acid could prove beneficial to subsequent neurodevelopment.

  7. Suitability of bronopol preservative treated milk for fatty acid determination.

    PubMed

    Butler, Gillian; Stergiadis, Sokratis

    2011-05-01

    This work aimed to test if milk preserved with bronopol can be reliably used for fatty acid determination. Dairy production and milk quality are often monitored regularly to assess performance and contribute to selection indices. With evidence that fat composition can be influenced by selective breeding, there might be an interest in using samples collected in routine testing to evaluate individual cow fatty acid profiles, contributing to breeding indices. However, most recording services use a preservative such as bronopol and there is no published record if this influences subsequent fatty acid analysis. This study used milk from an oil seed supplementation trial, generating a wide range of milk fatty acid profiles, to test if the concentration of 31 individual fatty acids determined by GC were influenced by bronopol. Provided preserved samples are subsequently frozen, milk treated with bronopol can reliably be used to evaluate fatty acid composition in most cases; however bronopol might influence a few long-chain fatty acids present in relatively low concentrations. This is one small step towards simplifying milk compositional analysis but it could ultimately streamline the inclusion of milk fat quality into breeding indices, either with a view to 'healthier' milk or potentially reducing methane output and the environmental impact of dairy production.

  8. Effect of salinity on the fatty acid and triacylglycerol composition of five haptophyte algae from the genera Coccolithophora, Isochrysis and Prymnesium determined by LC-MS/APCI.

    PubMed

    Nedbalová, Linda; Střížek, Antonín; Sigler, Karel; Řezanka, Tomáš

    2016-10-01

    Non-aqueous reversed-phase high-performance liquid chromatography (NARP-HPLC) with atmospheric pressure chemical ionization (APCI) was used for separation of triacylglycerols from five strains of haptophyte algae (genera Coccolithophora, Isochrysis, and Prymnesium). This study describes the separation and identification of C18 polyunsaturated triacylglycerols containing stearidonic and octadecapentaenoic fatty acids, including their regioisomers. Salinity affects the proportion of saturated and unsaturated fatty acids. The biosynthesis of C18 polyunsaturated triacylglycerols was found to be very stereospecific and to depend on the salinity of cultivation media, asymmetric regioisomers predominating at low salinity (sn-OpOpSt and/or PoStSt) and symmetric ones at high salinity (sn-OpStOp and or StPoSt).

  9. Chromatographic determination of amino acids in foods.

    PubMed

    Peace, Robert W; Gilani, G Sarwar

    2005-01-01

    Amino acids in foods exist in a free form or bound in peptides, proteins, or nonpeptide bonded polymers. Naturally occurring L-amino acids are required for protein synthesis and are precursors for essential molecules, such as co-enzymes and nucleic acids. Nonprotein amino acids may also occur in animal tissues as metabolic intermediates or have other important functions. The development of bacterially derived food proteins, genetically modified foods, and new methods of food processing; the production of amino acids for food fortification; and the introduction of new plant food sources have meant that protein amino acids and amino acid enantiomers in foods can have both nutritional and safety implications for humans. There is, therefore, a need for the rapid and accurate determination of amino acids in foods. Determination of the total amino acid content of foods requires protein hydrolysis by various means that must take into account variations in stability of individual amino acids and resistance of different peptide bonds to the hydrolysis procedures. Modern methods for separation and quantitation of free amino acids either before or after protein hydrolysis include ion exchange chromatography, high performance liquid chromatography (LC), gas chromatography, and capillary electrophoresis. Chemical derivatization of amino acids may be required to change them into forms amenable to separation by the various chromatographic methods or to create derivatives with properties, such as fluorescence, that improve their detection. Official methods for hydrolysis and analysis of amino acids in foods for nutritional purposes have been established. LC is currently the most widely used analytical technique, although there is a need for collaborative testing of methods available. Newer developments in chromatographic methodology and detector technology have reduced sample and reagent requirements and improved identification, resolution, and sensitivity of amino acid analyses

  10. DETERMINATION OF PESTICIDES IN COMPOSITE BEVERAGE SAMPLES

    EPA Science Inventory

    USEPA's National Exposure Research Laboratory conducts research to measure the exposure of individuals to chemical pollutants through the diet, as well as other media. In support of this research, methods are being evaluated for determination of pesticides in composite dietary s...

  11. Fatty acid composition of fat depots in wintering Canada geese

    USGS Publications Warehouse

    Austin, J.E.

    1993-01-01

    I determined the fatty acid composition of subcutaneous, abdominal, visceral, and leg saddle depots in adult female Canada Geese (Branta canadensis) wintering in north-central Missouri during October 1984-March 1985. Mean levels of C14:0, C16:0, C16:1, C18:0, C18:1, C18:2, and C18:3 generally were highest in the subcutaneous and abdominal depots. The ratio of saturated to unsaturated fats was highest in the leg saddle depot and lowest in the abdominal depot. I also assessed the differences among sexes, seasons, and years in fatty acid composition of abdominal fat depots in adult geese collected during October-March, 1985-1987. Adult females had consistently higher levels of C14:0 in abdominal depots than males. Fatty acid composition of the abdominal depot differed among years but not by season. In the abdominal depot, C14:0, C16:0, C16:1, and C18:1 were higher in 1986-1987 compared with the previous two years, whereas C18:3 was highest in 1984-1985. Differences among years reflected changes in winter diet. Fatty acids of wintering geese were similar to those previously found in breeding Canada Geese.

  12. Sensitive and selective electrochemical determination of quinoxaline-2-carboxylic acid based on bilayer of novel poly(pyrrole) functional composite using one-step electro-polymerization and molecularly imprinted poly(o-phenylenediamine).

    PubMed

    Yang, Yukun; Fang, Guozhen; Wang, Xiaomin; Pan, Mingfei; Qian, Hailong; Liu, Huilin; Wang, Shuo

    2014-01-01

    A facile and efficient molecularly imprinted polymer (MIP) recognition element of electrochemical sensor was fabricated by directly electro-polymerizing monomer o-phenylenediamine (oPD) in the presence of template quinoxaline-2-carboxylic acid (QCA), based on one-step controllable electrochemical modification of poly(pyrrole)-graphene oxide-binuclear phthalocyanine cobalt (II) sulphonate (PPY-GO-BiCoPc) functional composite on glassy carbon electrode (GCE). The MIP film coated on PPY-GO-BiCoPc functional composite decorated GCE (MIP/PPY-GO-BiCoPc/GCE) was presented for the first time. The synergistic effect and electro-catalytic activity toward QCA redox of PPY-GO-BiCoPc functional composite were discussed using various contrast tests. Also, the effect of experimental variables on the current response such as, electro-polymerization cycles, template/monomer ratio, elution condition for template removal, pH of the supporting electrolyte and accumulation time, were investigated in detail. Under the optimized conditions, the proposed MIP sensor possessed a fast rebinding dynamics and an excellent recognition capacity to QCA, while the anodic current response of square wave voltammetry (SWV) was well-proportional to the concentration of QCA in the range of 1.0×10(-8)-1.0×10(-4) and 1.0×10(-4)-5.0×10(-4) mol L(-1) with a low detection limit of 2.1 nmol L(-1). The established sensor was applied successfully to determine QCA in commercial pork and chicken muscle samples with acceptable recoveries (91.6-98.2%) and satisfactory precision (1.9-3.5% of SD), demonstrating a promising feature for applying the MIP sensor to the measurement of QCA in real samples.

  13. Sensitive and selective determining ascorbic acid and activity of alkaline phosphatase based on electrochemiluminescence of dual-stabilizers-capped CdSe quantum dots in carbon nanotube-nafion composite.

    PubMed

    Ma, Xiaolong; Zhang, Xin; Guo, Xinli; Kang, Qi; Shen, Dazhong; Zou, Guizheng

    2016-07-01

    Sensitive and selective determining bio-related molecule and enzyme play an important role in designing novel procedure for biological sensing and clinical diagnosis. Herein, we found that dual-stabilizers-capped CdSe quantum dots (QDs) in composite film of multi-walled carbon nanotubes (CNTs) and Nafion, displaying eye-visible monochromatic electrochemiluminescence (ECL) with fwhm of 37nm, which offers promising ECL signal for detecting ascorbic acid (AA) as well as the activity of alkaline phosphatase (ALP) in biological samples. It was also shown that the dual-stabilizers-capped CdSe QDs can preserve their highly passivated surface states with prolonged lifetime of excited states in Nafion mixtures, and facilitate electron-transfer ability of Nafion film along with CNTs. Compared with the QDs/GCE, the ECL intensity is enhanced 1.8 times and triggering potential shifted to lower energy by 0.12V on the CdSe-CNTs-Nafion/GCE. The ECL quenching degree increases with increasing concentration of AA in the range of 0.01-30nM with a limit of detection (LOD) of 5pM. The activity of ALP was determined indirectly according to the concentration of AA, generated in the hydrolysis reaction of l-ascorbic acid 2-phosphate sesquimagnesium (AA-P) in the presence of ALP as a catalyst, with an LOD of 1μU/L. The proposed strategy is favorable for developing simple ECL sensor or device with high sensitivity, spectral resolution and less electrochemical interference. PMID:27154663

  14. Thermal properties of epoxy composites filled with boric acid

    NASA Astrophysics Data System (ADS)

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

    2015-04-01

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

  15. DEOXYRIBONUCLEIC ACID BASE COMPOSITION OF PROTEUS AND PROVIDENCE ORGANISMS

    PubMed Central

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

    1962-01-01

    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. PMID:13891463

  16. Spectrofluorimetric determination of ellagic acid in brandy.

    PubMed

    Sádecká, Jana; Tóthová, Jana

    2012-12-01

    Two spectrofluorimetric methods have been developed for the rapid determination of ellagic acid. The first method is based on the complex formation between ellagic acid and borax in methanol solution. The fluorescence of the complex is monitored at an emission wavelength of 456nm with excitation at 383nm. Linear calibration curve was obtained from 2.5×10(-8) to 7.5×10(-7)molL(-1) and the limit of determination was 4×10(-9)molL(-1). The second method is based on the complex formation between ellagic acid and boric acid in ethanol solution. The fluorescence of the complex is monitored at an emission wavelength of 447nm with excitation at 387nm. Linear calibration curve was obtained from 1.25×10(-7) to 1.00×10(-6)molL(-1) and the limit of determination was 7×10(-9)molL(-1). The methods were successfully applied for the determination of ellagic acid in brandy samples. The results were found to be in good agreement with those obtained by HPLC method. PMID:22953802

  17. 31 CFR 359.14 - How are composite rates determined?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance:Treasury 2 2012-07-01 2012-07-01 false How are composite rates determined... BONDS, SERIES I General Information § 359.14 How are composite rates determined? Composite rates are set... composite interest rates.): Composite rate = {(Fixed rate ÷ 2) + Semiannual inflation rate + } × 2. 2...

  18. 31 CFR 359.14 - How are composite rates determined?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 2 2013-07-01 2013-07-01 false How are composite rates determined... BONDS, SERIES I General Information § 359.14 How are composite rates determined? Composite rates are set... composite interest rates.): Composite rate = {(Fixed rate ÷ 2) + Semiannual inflation rate + } × 2. 2...

  19. 31 CFR 359.14 - How are composite rates determined?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false How are composite rates determined... BONDS, SERIES I General Information § 359.14 How are composite rates determined? Composite rates are set... composite interest rates.): Composite rate = {(Fixed rate ÷ 2) + Semiannual inflation rate + } × 2. 2...

  20. 31 CFR 359.14 - How are composite rates determined?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 2 2011-07-01 2011-07-01 false How are composite rates determined... BONDS, SERIES I General Information § 359.14 How are composite rates determined? Composite rates are set... composite interest rates.): Composite rate = {(Fixed rate ÷ 2) + Semiannual inflation rate + } × 2. 2...

  1. A method for determining the composition of methanol-trimethyl borate mixtures

    NASA Technical Reports Server (NTRS)

    Kaye, Samuel; Sordyl, Frank

    1955-01-01

    A study of mixtures of pure methanol and trimethyl borate showed that the composition can be accurately obtained by a simple density determination. The refractive-index determination gives the composition with much less accuracy. The potentiometric titration of boric acid is also discussed.

  2. RNAi knockdown of fatty acid elongase1 alters fatty acid composition in Brassica napus.

    PubMed

    Shi, Jianghua; Lang, Chunxiu; Wu, Xuelong; Liu, Renhu; Zheng, Tao; Zhang, Dongqing; Chen, Jinqing; Wu, Guanting

    2015-10-23

    The quality and end-use of oil from oilseed crops is determined by its fatty acid composition. In particular, the relative proportions of erucic and oleic acids are key selection traits for breeders. The goal of our research is to genetically improve the nutritional quality of Brassica napus cultivar CY2, the oil of which is high in erucic acid (about 40%) and low in oleic acid (about 20%). Here, we report the use of a seed-specific napin A promoter to drive the knockdown of BnFAE1 in transgenic CY2. Southern blotting results confirmed the presence of the transgene. RT-PCR analysis showed that the levels of BnFAE1 were greatly decreased in BnFAE1-Ri lines compared with the CY2 cultivar. Knockdown of BnFAE1 sharply decreased the levels of erucic acid (less than 3%), largely increased the contents of oleic acid (more than 60%) and slightly increased the polyunsaturated chain fatty acids. Compared with high erucic acid parents, expression of BnFAE1 was dramatically decreased in developing F1 seeds derived from reciprocally crossed BnFAE1-Ri lines and high erucic acid cultivars. In addition, F1 seeds derived from reciprocal crosses between BnFAE1-Ri lines and high erucic acid cultivars showed significantly increased oleic acid (more than 52%) and sharply decreased erucic acid (less than 4%), demonstrating that the RNAi construct of BnFAE1 can effectively interfere with the target gene in F1 seeds. Taken together, our results demonstrate that BnFAE1 is a reliable target for genetic improvement of rapeseed in seed oil quality promotion.

  3. Gas Chromatographic Determination of Fatty Acid Compositions.

    ERIC Educational Resources Information Center

    Heinzen, Horacio; And Others

    1985-01-01

    Describes an experiment that: (1) has a derivation step using readily available reagents; (2) requires limited manipulative skills, centering attention on methodology; (3) can be completed within the time constraints of a normal laboratory period; and (4) investigates materials that are easy to acquire and are of great technical/biological…

  4. Fatty acids composition of Spanish black (Morus nigra L.) and white (Morus alba L.) mulberries.

    PubMed

    Sánchez-Salcedo, Eva M; Sendra, Esther; Carbonell-Barrachina, Ángel A; Martínez, Juan José; Hernández, Francisca

    2016-01-01

    This research has determined qualitatively and quantitatively the fatty acids composition of white (Morus alba) and black (Morus nigra) fruits grown in Spain, in 2013 and 2014. Four clones of each species were studied. Fourteen fatty acids were identified and quantified in mulberry fruits. The most abundant fatty acids were linoleic (C18:2), palmitic (C16:0), oleic (C18:1), and stearic (C18:0) acids in both species. The main fatty acid in all clones was linoleic (C18:2), that ranged from 69.66% (MN2) to 78.02% (MA1) of the total fatty acid content; consequently Spanish mulberry fruits were found to be rich in linoleic acid, which is an essential fatty acid. The fatty acid composition of mulberries highlights the nutritional and health benefits of their consumption.

  5. Fatty acids composition of Spanish black (Morus nigra L.) and white (Morus alba L.) mulberries.

    PubMed

    Sánchez-Salcedo, Eva M; Sendra, Esther; Carbonell-Barrachina, Ángel A; Martínez, Juan José; Hernández, Francisca

    2016-01-01

    This research has determined qualitatively and quantitatively the fatty acids composition of white (Morus alba) and black (Morus nigra) fruits grown in Spain, in 2013 and 2014. Four clones of each species were studied. Fourteen fatty acids were identified and quantified in mulberry fruits. The most abundant fatty acids were linoleic (C18:2), palmitic (C16:0), oleic (C18:1), and stearic (C18:0) acids in both species. The main fatty acid in all clones was linoleic (C18:2), that ranged from 69.66% (MN2) to 78.02% (MA1) of the total fatty acid content; consequently Spanish mulberry fruits were found to be rich in linoleic acid, which is an essential fatty acid. The fatty acid composition of mulberries highlights the nutritional and health benefits of their consumption. PMID:26213011

  6. Deoxyribonucleic acid base compositions of dermatophytes.

    PubMed

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

    1980-06-01

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

  7. The moon: Composition determined by nebular processes

    USGS Publications Warehouse

    Morgan, J.W.; Hertogen, J.; Anders, E.

    1978-01-01

    The bulk composition of the Moon was determined by the conditions in the solar nebula during its formation, and may be quantitatively estimated from the premise that the terrestrial planets were formed by cosmochemical processes similar to those recorded in the chondrites. The calculations are based on the Ganapathy-Anders 7-component model using trace element indicators, but incorportate improved geophysical data and petrological constraints. A model Moon with 40 ppb U, a core 2% by weight (1.8% metal with ???35% Ni and 0.2% FeS) and Mg/(Fe2++Mg)?????0.75 meets the trace element restrictions, and has acceptable density, heat flow and moment of inertia ratio. The high Ni content of the core permits low-Ti mare basalts to equilibrate with metal, yet still retain substantial Ni. The silicate resembles the Taylor-Jakes?? composition (and in some respects the waif Ganapathy-Anders Model 2a), but has lower SiO2. Minor modifications of the model composition (U=30-35 ppb) yield a 50% melt approximating Apollo 15 green glass and a residuum of olivine plus 3 to 4% spinel; the low SiO2, favors spinel formation, and, contrary to expectation, Cr is not depleted in the liquid. There may no longer be any inconsistency between the cosmochemical approach and arguments based on experimental petrology. ?? 1978 D. Reidel Publishing Company.

  8. Adaptive amino acid composition in collagens of parasitic nematodes.

    PubMed

    Hughes, Austin L

    2015-04-01

    Amino acid composition was analyzed in the glycine-rich repeat region of 306 collagens belonging to three major families of collagens from both parasitic and free-living nematodes. The collagens of parasitic species showed a tendency toward decreased usage of the hydrophilic residues A, D, and Q and increased usage of the hydrophobic resides I, L, and M; and this trend was seen in parasitic species of both the order Rhabdita and the order Spirurida. The amino acid composition of collagens of parasitic Rhabdita thus tended to resemble those of Spirurida more than that of free-living Rhabdita, suggesting an association between amino acid composition and a parasitic lifestyle. Computer predictions suggested that the more hydrophobic amino acid composition was associated with a reduction of the propensity towards B-cell epitope formation, suggesting that evasion of host immune responses may be a major selective factor responsible for the parasite-specific trend in collagen amino acid composition.

  9. A comparative study of the fatty acid composition of prochloron lipids

    NASA Technical Reports Server (NTRS)

    Kenrick, J. R.; Deane, E. M.; Bishop, D. G.

    1983-01-01

    The chemical analysis of lipids of Prochloron isolated from several hosts is discussed. The object was to determine whether differences in lipid composition could be used to characterize organisms from different sources. Major lipid components are given. An analysis of fatty acid composition of individual lipids slowed a distinctive disstribution of fatty acids. While present results do not justify the use of fatty acid content in the taxonomy of Prochlon, the variations found in the lipids of cells from the same host harvested from different areas, or at different times in the same area, suggest that a study of the effects of temperature and light intensity on lipid composition would be rewarding.

  10. Sequential injection redox or acid-base titration for determination of ascorbic acid or acetic acid.

    PubMed

    Lenghor, Narong; Jakmunee, Jaroon; Vilen, Michael; Sara, Rolf; Christian, Gary D; Grudpan, Kate

    2002-12-01

    Two sequential injection titration systems with spectrophotometric detection have been developed. The first system for determination of ascorbic acid was based on redox reaction between ascorbic acid and permanganate in an acidic medium and lead to a decrease in color intensity of permanganate, monitored at 525 nm. A linear dependence of peak area obtained with ascorbic acid concentration up to 1200 mg l(-1) was achieved. The relative standard deviation for 11 replicate determinations of 400 mg l(-1) ascorbic acid was 2.9%. The second system, for acetic acid determination, was based on acid-base titration of acetic acid with sodium hydroxide using phenolphthalein as an indicator. The decrease in color intensity of the indicator was proportional to the acid content. A linear calibration graph in the range of 2-8% w v(-1) of acetic acid with a relative standard deviation of 4.8% (5.0% w v(-1) acetic acid, n=11) was obtained. Sample throughputs of 60 h(-1) were achieved for both systems. The systems were successfully applied for the assays of ascorbic acid in vitamin C tablets and acetic acid content in vinegars, respectively.

  11. Folic Acid Determination Using Electrochemical Sensors

    PubMed Central

    Mirmoghtadaie, Leila; Shamaeizadeh, Nahal; Mirzanasiri, Nooshin

    2015-01-01

    Folic acid (FA) is a water soluble vitamin that exists in many natural species. The lack of FA causes some deficiencies in the human body, so finding a simple and sensitive method for determining the FA is important. One of the modern techniques which overcome the disadvantages of conventional determination methods is the sensors. Possibility of miniaturization, the development of microfabricated electrochemical (EC) sensors has resulted in high sensitivity, portability, improved performance and spatial resolution, low power consumption, and the opportunity for integration with other technologies made Micro-Electrical-Mechanical Systems-based EC sensors suitable to identify low concentration analytes and microorganisms in a variety of mediums. PMID:26605021

  12. Interconnection between the protein solubility and amino acid and dipeptide compositions.

    PubMed

    Niu, Xiaohui; Li, Nana; Chen, Dinyan; Wang, Zengzhen

    2013-01-01

    Obtaining soluble proteins in sufficient concentrations helps increase the overall success rate in various experimental studies. Protein solubility is an individual trait ultimately determined by its primary protein sequence. Exploring the interconnection between the protein solubility and the compositions of protein sequence is instrumental for setting priorities on targets in large scale proteomics projects. In this paper, amino acid composition (20 dimensions) and the dipeptide composition (400 dimensions) were extracted to form the total candidate feature pool (420 dimensions), and each feature was selected into the feature vectors one by one, which were sorted by the absolute value of the correlation coefficient. Finally, we evaluated and recorded the 420 results of Support Vector Machine (SVM) as the prediction engine. According to the results of SVM, the first 208 features were chosen from the 420 dimensions, which were considered as the efficient ones. By analyzing the composition of the former 208 features, we found that the protein solubility was significantly influenced by the occurrence frequencies of the acidic amino acids, basic amino acids, non-polar hydrophobic amino acids and the two polar neutral amino acids(C, Q) in the protein sequences. Additionally, we detected that the dipeptides composed by the acidic amino acids (D, E) and basic amino acids (K, R and H), especially the dipeptide composed by the acidic amino acids (D, E), had strong interconnection with the protein solubility.

  13. Composition of Humic Acids of the Lake Baikal Sediments

    NASA Astrophysics Data System (ADS)

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

    2012-04-01

    Humic substances are the final stage of the biogeochemical transformation of organic matter in the biosphere. Its natural compounds are found not only in soil, peat, coal, and sediments of basins. Chemical composition and properties of humic substances are determined by the functioning of the ecosystem as a whole. Therefore the study of the unique Lake Baikal sediments can provide information about their genesis, as well as the processes of organic matter transformation. For this purpose, preparations of humic acids (HA) were isolated by alkaline extraction method. The composition of HA was investigated by the elemental analyzer CHNS/O PerkinElmer Series II. Various located sediments of the Lake Baikal were the objects of the study: 1 - Chivyrkuisky Bay, 2 - Kotovo Bay, 3 - Selenga river delta near Dubinino village, 4 - Selenga river delta near Murzino village. Data on the elemental composition of HA in terms of ash-free portion show that the carbon content (CC) is of 50-53% with a maximum value in a sample 3, and minimum - in a sample 2. Such values are characteristic also for the soils with low biochemical activity. The hydrogen content is of 4,2-5,3%, a maximum value is in a sample 1. Data recalculation to the atomic percentages identified following regularities. The CC of HA is of 35-39 at. %. Hydrogen content is of 37-43 at. %. According to the content of these elements investigated substances are clearly divided into two groups: HA of the sediments of the Lake Baikal and river Selenga delta. The magnitude of the atomic ratio H/C can be seen varying degrees of condensation of the molecules of humic acids. The high atomic ratio H/C in HA of the former group indicates the predominance of aliphatic structures in the molecules. Humic acids of the later group are characterized by a low value H/C (<1), suggesting a large proportion of aromatic components in HA composition. In sediments of the Selenga river delta there is an addition of organic matter of terrigenous

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

    PubMed

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

    2015-05-01

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

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

    PubMed

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

    2015-05-01

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

  16. Proximate composition, fatty acid analysis and protein digestibility-corrected amino acid score of three Mediterranean cephalopods.

    PubMed

    Zlatanos, Spiros; Laskaridis, Kostas; Feist, Christian; Sagredos, Angelos

    2006-10-01

    Proximate composition, fatty acid analysis and protein digestibility-corrected amino acid score (PDCAAS) in three commercially important cephalopods of the Mediterranean sea (cuttlefish, octopus and squid) were determined. The results of the proximate analysis showed that these species had very high protein:fat ratios similar to lean beef. Docosahexaenoic, palmitic and eicosipentaenoic acid were the most abundant fatty acids among analyzed species. The amount of n-3 fatty acids was higher than that of saturated, monounsaturated and n-6 fatty acids. Despite the fact that cephalopods contain small amounts of fat they were found quite rich in n-3 fatty acids. Finally, PDCAAS indicated that these organisms had a very good protein quality.

  17. Advances in Food Composition Tables of Japan--Amino Acid, Fatty Acid and Available Carbohydrate Tables.

    PubMed

    Yasui, Takeshi

    2015-01-01

    The new revised version of the Standard Tables of Food Composition in Japan (STFCJ 2015) will be published in 2015. The aim of the present paper is to share information on issues we have encountered during the revision. New analytical data on amino acid composition will be provided for approximately 230 foods, fatty acid composition for approximately 140 foods, and available carbohydrate (starch, glucose, fructose, sucrose, maltose, and lactose) composition for approximately 340 foods. These data will be published separately as three supplements to the STFCJ 2015: amino acid tables, fatty acid tables, and available carbohydrate tables. Available carbohydrate tables will also provide polyol (sorbitol and mannitol) and organic acid (acetic acid, lactic acid, citric acid, etc.) data. In the supplements, amino acid content will be adjusted for protein content calculated as reference nitrogen multiplied by a nitrogen to protein conversion factor, and fatty acid content adjusted for extractable lipid content, as in previous revisions. Available carbohydrate content, however, will be adjusted for water content. Values of protein content calculated as the sum of amino acid residues , lipid content expressed as triacylglycerol equivalents of fatty acids , and available carbohydrate content will appear in the main tables of the STFCJ 2015. Protein, fat and available carbohydrate contents were significantly decreased when the preferred analytical methods of FAO were applied instead of the acceptable methods. Online publication of Japanese and English versions of these tables, reference materials, and a retrievable food composition database is planned. PMID:26598876

  18. Composition of acid tars from sulfuric acid treatment of petroleum oils

    SciTech Connect

    Frolov, A.F.; Denisova, T.L.; Karpova, I.V.; Titova, T.S.

    1986-01-01

    This paper examines the composition of freshly produced acid tars and pond tars, gives an analysis of the acid part of the tars, and obtains data on the change in composition of the acid tar in the course of storage--data that are needed in developing methods for utilizing the tar. The acid-pond tars consist of a mixture of hydrocarbons with a very low content of acids, whereas the freshly produced acid tars consist mainly of sulfuric acid, sulfonic acids, and carboxylic acids. In the course of storage, hardening of acid tars in the volume proceeds through reactions of polymerization, condensation, and oxidation of the surface layer that is in contact with air.

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

    PubMed Central

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

    2009-01-01

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

  20. Supramolecular structure of 5-aminosalycilic acid/halloysite composites.

    PubMed

    Viseras, Maria-Teresa; Aguzzi, Carola; Cerezo, Pilar; Cultrone, Giuseppe; Viseras, Cesar

    2009-05-01

    This paper assesses the supramolecular structure of nanocomposites prepared by including the anti-inflammatory drug 5-aminosalycilic acid in halloysite nanotubes. Halloysite tubes have sub-micron individual lengths with outer diameters ∼0.1 µm, as observed by FESEM. The mercury intrusion plots showed bimodal profiles with pore dimensions ∼10 and 0.06 µm. X-ray diffraction and thermogravimetric results revealed changes in the hydration form of the clay after the interaction. The groups associated to the interaction were studied by FTIR. The location of the drug in the composites was determined after uranium staining of its amino groups by X-EDS microanalysis coupled with HREM. The drug was located both inside and on the surface of the halloysite nanotubes. These results confirm the occurrence of two concomitant interaction mechanisms: rapid adsorption of 5-ASA at the external halloysite surface followed by slow adsorption of the drug inside the tubes.

  1. Determination of benzoic acid, chlorobenzoic acids and chlorendic acid in water

    SciTech Connect

    Dietz, E.A.; Cortellucci, N.J.; Singley, K.F. )

    1993-01-01

    To characterize and conduct treatment studies of a landfill leachate an analysis procedure was required to determine concentrations of benzoic acid, the three isomers of chlorobenzoic acid and chlorendic acid. The title compounds were isolated from acidified (pH 1) water by extraction with methyl t-butyl ether. Analytes were concentrated by back-extracting the ether with 0.1 N sodium hydroxide which was separated and acidified. This solution was analyzed by C[sub 18] reversed-phase HPLC with water/acetonitrile/acetic acid eluent and UV detection at 222 nm. The method has detection limits of 200 [mu]g/L for chlorendic acid and 100 [mu]g/L for benzoic acid and each isomer of chlorobenzoic acid. Validation studies with water which was fortified with the analytes at concentrations ranging from one to ten times detection limits resulted in average recoveries of >95%.

  2. Proximate composition, fatty acid and lipid class composition of the muscle from deep-sea teleosts and elasmobranchs.

    PubMed

    Økland, Hege M W; Stoknes, Iren S; Remme, Jannicke F; Kjerstad, Margareth; Synnes, Marianne

    2005-03-01

    Proximate composition of muscle was determined for the following deep-sea fish species: roughhead grenadier (Macrourus berglax), mora/deep-sea cod (Mora moro), Portuguese dogfish (Centroscymnus coelolepis), black dogfish (Centroscyllium fabricii), leafscale gulper shark (Centrophorus squamosus), greater lantern shark (Etmopterus princeps), smalleyed rabbitfish/ghostshark (Hydrolagus affinis), birdbeak dogfish (Deania calcea) and two species of smooth head (Alepocephalus bairdii and Alepocephalus agassizii). The first eight species contained less than 1% fat in the muscle, while the last two contained 3.0% and 3.6% fat, respectively. Fatty acid and lipid class composition was determined for the first five fish species and showed that the dominant class of lipids was phospholipids. The lipids consisted mainly of polyunsaturated fatty acids (PUFA), and docosahexaenoic acid (DHA) was the dominant fatty acid. Roughhead grenadier and mora showed resemblance to cod (Gadus morhua) regarding protein content, fat content and fatty acid composition. However, the muscle from the deep-sea fish species did contain a higher proportion of arachidonic acid (20:4n-6) than cod muscle.

  3. [HPTLC densitometric determination of free bile acids in bezoar].

    PubMed

    Zhang, Q; Li, S; Cheng, J; Yan, K; Tian, S

    1990-06-01

    Cholic acid (CA), chenodeoxycholic acid (CDCA) and deoxycholic acid (DCA) which are extracted with CH3OH from Bezoar can be separated on HPTLC silica gel plate (made in China) with isooctane-n-butyl acetate-acetic acid (4:2:1), and the three bile acids were determined by TLC densitometry.

  4. Compositions and method for controlling precipitation when acidizing sour wells

    SciTech Connect

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

    1989-12-19

    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.

  5. Determination of free fatty acids in beer.

    PubMed

    Bravi, Elisabetta; Marconi, Ombretta; Sileoni, Valeria; Perretti, Giuseppe

    2017-01-15

    Free fatty acids (FFA) content of beer affects the ability to form a stable head of foam and plays an important role in beer staling. Moreover, the presence of saturated FAs is related sometimes to gushing problems in beer. The aim of this research was to validate an analytical method for the determination of FFAs in beer. The extraction of FFAs in beer was achieved via Liquid-Liquid Cartridge Extraction (LLCE), the FFAs extract was purified by Solid Phase Extraction (SPE), methylated by boron trifluoride in methanol, and injected into GC-FID system. The performance criteria demonstrate that this method is suitable for the analysis of medium and long chain FFAs in beer. The proposed method was tested on four experimental beers.

  6. Determination of free fatty acids in beer.

    PubMed

    Bravi, Elisabetta; Marconi, Ombretta; Sileoni, Valeria; Perretti, Giuseppe

    2017-01-15

    Free fatty acids (FFA) content of beer affects the ability to form a stable head of foam and plays an important role in beer staling. Moreover, the presence of saturated FAs is related sometimes to gushing problems in beer. The aim of this research was to validate an analytical method for the determination of FFAs in beer. The extraction of FFAs in beer was achieved via Liquid-Liquid Cartridge Extraction (LLCE), the FFAs extract was purified by Solid Phase Extraction (SPE), methylated by boron trifluoride in methanol, and injected into GC-FID system. The performance criteria demonstrate that this method is suitable for the analysis of medium and long chain FFAs in beer. The proposed method was tested on four experimental beers. PMID:27542484

  7. Synthesis and application of molecularly imprinted poly(methacrylic acid)-silica hybrid composite material for selective solid-phase extraction and high-performance liquid chromatography determination of oxytetracycline residues in milk.

    PubMed

    Lv, Yun-Kai; Wang, Li-Min; Yang, Lei; Zhao, Chen-Xi; Sun, Han-Wen

    2012-03-01

    A novel molecularly imprinted organic-inorganic hybrid composite material (MIP-HCM) was developed based on molecular imprinting technique in combination with hybrid composite synthesis and sol-gel technology for selective solid-phase extraction (SPE) of tetracyclines residues in milk. The MIP-HCM was prepared using oxytetracycline as the template, methacrylic acid as organic functional monomer, tetraethoxysilane as inorganic precursor and methacryloxypropyltrimethoxysilane as the coupling agent. Synthesis conditions are optimized by changing some factors to obtain sorbent with the controllable adsorption capacity, selectivity, hardness and toughness. Binding study demonstrated that the imprinted hybrid composites showed excellent affinity and high selectivity to oxytetracycline. An enrichment factor of 18.8 along with a good sample clean-up was obtained under the optimized SPE conditions. The average recoveries of three tetracyclines antibiotics spiked milk at 0.1, 0.2 and 0.5 mg kg⁻¹ were in the range of 80.9-104.3% with the precision of 1.5-5.0%. The limits of detection and quantitation of the proposed method were in a range of 4.8-12.7 μg kg⁻¹ and 16.0-42.3 μg kg⁻¹, respectively.

  8. Maximized PUFA measurements improve insight in changes in fatty acid composition in response to temperature.

    PubMed

    van Dooremalen, Coby; Pel, Roel; Ellers, Jacintha

    2009-10-01

    A general mechanism underlying the response of ectotherms to environmental changes often involves changes in fatty acid composition. Theory predicts that a decrease in temperature causes an increase in unsaturation of fatty acids, with an important role for long-chain poly-unsaturated fatty acids (PUFAs). However, PUFAs are particularly unstable and susceptible to peroxidation, hence subtle differences in fatty acid composition can be challenging to detect. We determined the fatty acid composition in springtail (Collembola) in response to two temperatures (5 degrees C and 25 degrees C). First, we tested different sample preparation methods to maximize PUFAs. Treatments consisted of different solvents for primary lipid extraction, mixing with antioxidant, flushing with inert gas, and using different temperature exposures during saponification. Especially slow saponification at low temperature (90 min at 70 degrees C) in combination with replacement of headspace air with nitrogen during saponification and methylation maximized PUFAs for GC analysis. Applying these methods to measure thermal responses in fatty acid composition, the data showed that the (maximized) proportion of C(20) PUFAs increased at low acclimation temperature. However, C(18) PUFAs increased at high acclimation temperature, which is contrary to expectations. Our study illustrates that PUFA levels in lipids may often be underestimated and this may hamper a correct interpretation of differential responses of fatty acid composition. PMID:19557745

  9. Maximized PUFA measurements improve insight in changes in fatty acid composition in response to temperature.

    PubMed

    van Dooremalen, Coby; Pel, Roel; Ellers, Jacintha

    2009-10-01

    A general mechanism underlying the response of ectotherms to environmental changes often involves changes in fatty acid composition. Theory predicts that a decrease in temperature causes an increase in unsaturation of fatty acids, with an important role for long-chain poly-unsaturated fatty acids (PUFAs). However, PUFAs are particularly unstable and susceptible to peroxidation, hence subtle differences in fatty acid composition can be challenging to detect. We determined the fatty acid composition in springtail (Collembola) in response to two temperatures (5 degrees C and 25 degrees C). First, we tested different sample preparation methods to maximize PUFAs. Treatments consisted of different solvents for primary lipid extraction, mixing with antioxidant, flushing with inert gas, and using different temperature exposures during saponification. Especially slow saponification at low temperature (90 min at 70 degrees C) in combination with replacement of headspace air with nitrogen during saponification and methylation maximized PUFAs for GC analysis. Applying these methods to measure thermal responses in fatty acid composition, the data showed that the (maximized) proportion of C(20) PUFAs increased at low acclimation temperature. However, C(18) PUFAs increased at high acclimation temperature, which is contrary to expectations. Our study illustrates that PUFA levels in lipids may often be underestimated and this may hamper a correct interpretation of differential responses of fatty acid composition.

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

    PubMed Central

    Streeter, John G.

    1987-01-01

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

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

    SciTech Connect

    Maita, Y.; Kawaguchi, S. )

    1989-09-01

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

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

    PubMed Central

    Colwell, R. R.; Mandel, M.

    1965-01-01

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

  13. Nucleic acids, compositions and uses thereof

    DOEpatents

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

    2012-02-21

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

  14. Nucleic acid compositions and the encoding proteins

    SciTech Connect

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

    2014-09-02

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

  15. Development of a novel naphthoic acid ionic liquid and its application in "no-organic solvent microextraction" for determination of triclosan and methyltriclosan in human fluids and the method optimization by central composite design.

    PubMed

    Wang, Hui; Gao, Jiajia; Yu, Nana; Qu, Jingang; Fang, Fang; Wang, Huili; Wang, Mei; Wang, Xuedong

    2016-07-01

    In traditional ionic liquids (ILs)-based microextraction, the hydrophobic and hydrophilic ILs are often used as extractant and disperser, respectively. However, the functional effects of ILs are not utilized in microextraction procedures. Herein, we introduced 1-naphthoic acid into imidazolium ring to synthesize a novel ionic liquid 1-butyl-3-methylimidazolium naphthoic acid salt ([C4MIM][NPA]), and its structure was characterized by IR, (1)H NMR and MS. On the basis of its acidic property and lower solubility than common [CnMIM][BF4], it was used as a mixing dispersive solvent with [C4MIM][BF4] in "functionalized ionic liquid-based no organic solvent microextraction (FIL-NOSM)". Utilization of [C4MIM][NPA] in FIL-NOSM procedures has two obvious advantages: (1) it promoted the non-polar environment, increased volume of the sedimented phase, and thus could enhance the extraction recoveries of triclosan (TCS) and methyltriclosan (MTCS) by more than 10%; and (2) because of the acidic property, it can act as a pH modifier, avoiding extra pH adjustment step. By combining single factor optimization and central composite design, the main factors in the FIL-NOSM method were optimized. Under the optimal conditions, the relative recoveries of TCS and MTCS reached up to 98.60-106.09%, and the LODs of them were as low as 0.12-0.15µgL(-1) in plasma and urine samples. In total, this [C4MIM][NPA]-based FIL-NOSM method provided high extraction efficiency, and required less pretreatment time and unutilized any organic solvent. To the best of our knowledge, this is the first application of [C4mim][NPA]-based microextraction method for the simultaneous quantification of trace TCS and MTCS in human fluids. PMID:27154690

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

    PubMed Central

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

    2013-01-01

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

  17. Amino acid composition in parenteral nutrition: what is the evidence?

    PubMed Central

    Yarandi, Shadi S.; Zhao, Vivian M.; Hebbar, Gautam; Ziegler, Thomas R.

    2011-01-01

    Purpose of review Complete parenteral nutrition solutions contain mixed amino acid products providing all nine essential amino acids and a varying composition of nonessential amino acids. Relatively little rigorous comparative efficacy research on altered parenteral nutrition amino acid composition has been published in recent years. Recent findings Limited data from randomized, double-blind, adequately powered clinical trials to define optimal doses of total or individual amino acids in parenteral nutrition are available. An exception is the growing number of studies on the efficacy of glutamine supplementation of parenteral nutrition or given as a single parenteral agent. Parenteral glutamine appears to confer benefit in selected patients; however, additional data to define optimal glutamine dosing and the patient subgroups who may most benefit from this amino acid are needed. Although some promising studies have been published, little data are available in the current era of nutrition support on the clinical efficacy of altered doses of arginine, branched chain amino acids, cysteine, or taurine supplementation of parenteral nutrition. Summary Despite routine use of parenteral nutrition, surprisingly little clinical efficacy data are available to guide total or specific amino acid dosing in adult and pediatric patients requiring this therapy. This warrants increased attention by the research community and funding agencies to better define optimal amino acid administration strategies in patient subgroups requiring parenteral nutrition. PMID:21076291

  18. Determination of Perfluorocarboxylic Acids in Sludge

    EPA Science Inventory

    Methods were developed for the extraction from wastewater-treatment sludge and quantitation by LC/MS/MS of perfluorocarboxylic acids (PFCAs, C6 to C12), 7-3 fluorotelomer carboxylic acid (7-3 FTCA) and 8-2 fluorotelomer 2-unsaturated carboxylic acid (8-2 FTUCA) using LC/MS/MS.

  19. Genotype, production system and sex effects on fatty acid composition of meat from goat kids.

    PubMed

    Özcan, Mustafa; Demirel, Gulcan; Yakan, Akın; Ekiz, Bülent; Tölü, Cemil; Savaş, Türker

    2015-02-01

    Two trials were performed to assess the meat fatty acid profile of goat kids from different genotypes, production systems and sex. In the first trial, genotype effect was determined in 24 suckling male kids from Turkish Saanen, Maltese and Gokceada breeds. In the second trial, male and female Gokceada Goat kids were used to compare the effect of extensive and semi-intensive production systems on fatty acid composition of meat. Significant genotype effect was observed in the percentages of myristic acid (C14:0), palmitic acid (C16:0), oleic acid (C18:1 n-9), linolenic acid (C18:3 n-3), arachidonic acid (C20:4 n-6) and docosahexaenoic acid (C22:6 n-3), despite no differences on the ratios of polyunsaturated fatty acids to saturated fatty acids (PUFA/SFA) and n-6/n-3 (P > 0.05). The effect of production system had also significant effects on fatty acids, but sex only influenced significantly stearic acid (C18:0), C18:1 n-9 and C18:3 n-3 fatty acids and total PUFA level and PUFA/SFA ratio. This study confirms that dairy breeds are prone to produce higher levels of unsaturated fatty acids in their muscle. Meanwhile, meat from Gokceada goat kids, which is one of the indigenous breeds in Turkey, had similar PUFA/SFA and n-6/n-3 ratios to Turkish Saanen and Maltase.

  20. Determination of isocyanic acid in air.

    PubMed

    Karlsson, D; Dalene, M; Skarping, G; Marand, A

    2001-08-01

    A method is presented for the determination of isocyanic acid (ICA), HNCO, in air samples as a di-n-butylamine (DBA) derivative. The method is based on sampling in midget impinger flasks containing 10 ml of 0.01 mol l-1 DBA in toluene. Quantification was made using liquid chromatography (LC) and electrospray mass spectrometry (MS) monitoring positive ions. The instrumental detection limit for the LC-MS was 10 fmol of ICA-DBA. ICA was generated by thermal decomposition of urea. A standard solution containing the DBA derivatives of ICA was prepared by collecting the emitted ICA in an impinger flask containing DBA. ICA in the reference solution was characterised by LC and time-of-flight (TOF) MS and quantified by LC chemiluminescent nitrogen detection (LC-CLND). The instrumental detection limit for the LC-CLND was 1 ng of nitrogen. ICA was emitted during thermal degradation of PFU resins and polyurethane (PUR) lacquers, from car metal sheets. ICA was the most dominant isocyanate and in PUR coating up to 8% of the total weight was emitted as ICA and for PFU resins up to 14% was emitted as ICA. When air samples were collected in an iron foundry during casting in sand moulds with furan resins, concentrations of ICA in the range 50-700 micrograms m-3 were found in the working atmosphere. PMID:11523446

  1. Effect of Finishing System on Subcutaneous Fat Melting Point and Fatty Acid Composition

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Angus-cross steers (n = 69) were used to determine the effect of finishing system on subcutaneous fat melting point and fatty acid composition. Three finishing systems were evaluated: 1) mixed pasture for 134 d [MP], 2) mixed pasture for 93 d and alfalfa for 41 d [AL], or 3) concentrate finishing f...

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

    PubMed

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

    2011-12-01

    The fatty acid profile of hepatocytes and adipocytes is determined by the composition of the dietary lipids. It remains unclear which fatty acid components contribute to the development or reduction of insulin resistance. The present work examined the fatty acid composition of both tissues in sucrose-induced obese rats receiving fish oil to determine whether the effect of dietary (n-3) polyunsaturated fatty acids (PUFAs) on the reversion of metabolic syndrome in these rats is associated to changes in the fatty acid composition of hepatocyte and adipocyte membrane lipids. Animals with metabolic syndrome were divided into a corn-canola oil diet group and a fish oil diet group, and tissues fatty acids composition were analyzed after 6 weeks of dietary treatment. Fatty acid profiles of the total membrane lipids were modified by the fatty acid composition of the diets fed to rats. N-3 PUFAs levels in animals receiving the fish oil diet plus sucrose in drinking water were significantly higher than in animals under corn-canola oil diets. It is concluded that in sucrose-induced obese rats, consumption of dietary fish oil had beneficial effects on the metabolic syndrome and that such effects would be conditioned by the changes in the n-3 PUFAs composition in hepatic and adipose tissues because they alter membrane properties and modify the type of substrates available for the production of active lipid metabolites acting on insulin resistance and obesity. PMID:21695545

  3. Methods and compositions for efficient nucleic acid sequencing

    DOEpatents

    Drmanac, Radoje

    2002-01-01

    Disclosed are novel methods and compositions for rapid and highly efficient nucleic acid sequencing based upon hybridization with two sets of small oligonucleotide probes of known sequences. Extremely large nucleic acid molecules, including chromosomes and non-amplified RNA, may be sequenced without prior cloning or subcloning steps. The methods of the invention also solve various current problems associated with sequencing technology such as, for example, high noise to signal ratios and difficult discrimination, attaching many nucleic acid fragments to a surface, preparing many, longer or more complex probes and labelling more species.

  4. Methods and compositions for efficient nucleic acid sequencing

    DOEpatents

    Drmanac, Radoje

    2006-07-04

    Disclosed are novel methods and compositions for rapid and highly efficient nucleic acid sequencing based upon hybridization with two sets of small oligonucleotide probes of known sequences. Extremely large nucleic acid molecules, including chromosomes and non-amplified RNA, may be sequenced without prior cloning or subcloning steps. The methods of the invention also solve various current problems associated with sequencing technology such as, for example, high noise to signal ratios and difficult discrimination, attaching many nucleic acid fragments to a surface, preparing many, longer or more complex probes and labelling more species.

  5. Determining the Compositions of Extraterrestrial Lava Flows

    NASA Technical Reports Server (NTRS)

    Fink, Jonathan H.

    2002-01-01

    The primary purpose of this research project has been to develop techniques that allow the emplacement conditions of volcanic landforms on other planets to be related to attributes that can be remotely detected with available instrumentation. The underlying assumption of our work is that the appearance of a volcano, lava flow, debris avalanche, or exhumed magmatic intrusion can provide clues about the conditions operating when that feature was first emplaced. Magma composition, amount of crustal heat flow, state of tectonic stress, and climatic conditions are among the important variables that can be inferred from the morphology and texture of an igneous body.

  6. Effects of Biomass in Polyethylene or Polylactic Acid Composites

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  7. Corrosion of graphite composites in phosphoric acid fuel cells

    NASA Technical Reports Server (NTRS)

    Christner, L. G.; Dhar, H. P.; Farooque, M.; Kush, A. K.

    1986-01-01

    Polymers, polymer-graphite composites and different carbon materials are being considered for many of the fuel cell stack components. Exposure to concentrated phosphoric acid in the fuel cell environment and to high anodic potential results in corrosion. Relative corrosion rates of these materials, failure modes, plausible mechanisms of corrosion and methods for improvement of these materials are investigated.

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

    PubMed

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

    2004-03-01

    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.

  9. Analytical method for determination of benzene-arsenic acids

    SciTech Connect

    Mitchell, G.L.; Bayse, G.S.

    1988-01-01

    A sensitive analytical method has been modified for use in determination of several benzenearsonic acids, including arsanilic acid (p-aminobenzenearsonic acid), Roxarsone (3-nitro-4-hydroxybenzenearsonic acid), and p-ureidobenzene arsonic acid. Controlled acid hydrolysis of these compounds produces a quantitative yield of arsenate, which is measured colorimetrically as the molybdenum blue complex at 865 nm. The method obeys Beer's Law over the micromolar concentration range. These benzenearsonic acids are routinely used as feed additives in poultry and swine. This method should be useful in assessing tissue levels of the arsenicals in appropriate extracts.

  10. Translating plasma and whole blood fatty acid compositional data into the sum of eicosapentaenoic and docosahexaenoic acid in erythrocytes.

    PubMed

    Stark, Ken D; Aristizabal Henao, Juan J; Metherel, Adam H; Pilote, Louise

    2016-01-01

    Specific blood levels of eicosapentaenoic plus docosahexaenoic acid (EPA+DHA, wt% of total) in erythrocytes or "the omega-3 index" have been recommended for cardio-protection, but fatty acids are often measured in different blood fractions. The ability to estimate the % of EPA+DHA in erythrocytes from the fatty acid composition of other blood fractions would enable clinical assessments of omega-3 status when erythrocyte fractions are not available and increase the ability to compare blood levels of omega-3 fatty acids across clinical studies. The fatty acid composition of baseline plasma, erythrocytes and whole blood samples from participants (n=1104) in a prospective, multicenter study examining acute coronary syndrome were determined. The ability to predict the % of EPA+DHA in erythrocytes from other blood fractions were examined using bivariate and multiple linear regression modelling. Concordance analysis was also used to compare the actual erythrocytes EPA+DHA values to values estimated from other blood fractions. EPA+DHA in erythrocytes was significantly (p<0.001) correlated EPA+DHA in plasma (r(2)=0.54) and whole blood (r(2)=0.79). Using multiple linear regression to predict EPA+DHA in erythrocytes resulted in stronger coefficients of determination in both plasma (R(2)=0.70) and whole blood (R(2)=0.84). Concordance analyses indicated agreement between actual and estimated EPA+DHA in erythrocytes, although estimating from plasma fatty acids appears to require translation by categorization rather than by translation as continuous data. This study shows that the fatty acid composition of different blood fractions can be used to estimate erythrocyte EPA+DHA in a population with acute coronary syndrome.

  11. Perfluoroalkyl acid contamination and polyunsaturated fatty acid composition of French freshwater and marine fishes.

    PubMed

    Yamada, Ami; Bemrah, Nawel; Veyrand, Bruno; Pollono, Charles; Merlo, Mathilde; Desvignes, Virginie; Sirot, Véronique; Oseredczuk, Marine; Marchand, Philippe; Cariou, Ronan; Antignac, Jean-Phillippe; Le Bizec, Bruno; Leblanc, Jean-Charles

    2014-07-30

    In this study, French marine and freshwater fish perfluoroalkyl acid (PFAA) contamination are presented along with their fatty acid (FA) composition to provide further elements for a risk/benefit balance of fish consumption to be assessed. The 29 most consumed marine fish species were collected in four metropolitan French coastal areas in 2004 to constitute composite samples. Geographical differences in terms of consumed species and contamination level were taken into account. Three hundred and eighty-seven composite samples corresponding to 16 freshwater fish species collected between 2008 and 2010 in the six major French rivers or their tributaries were selected among the French national agency for water and aquatic environments freshwater fish sample library. The raw edible parts were analyzed for FA composition and PFAA contamination. Results show that freshwater fishes are more contaminated by PFAAs than marine fishes and do not share the same contamination profile. Freshwater fish contamination is mostly driven by perfluorooctane sulfonate (PFOS) (75%), whereas marine fish contamination is split between perfluorooctanoic acid (PFOA) (24%), PFOS (20%), perfluorohexanoic acid (PFHxA) (15%), perfluoropentanoic acid (PFHpA) (11%), and perfluorobutanoic acid (PFBA) (11%). Common carp, pike-perch, European perch, thicklip grey mullet, and common roach presented the most unfavorable balance profile due to their high level of PFAAs and low level of n-3 long-chain polyunsaturated fatty acids (LC-PUFAs). These data could be used, if needed, in an updated opinion on fish consumption that takes into account PFAA contamination.

  12. Thoron-tartaric acid systems for spectrophotometric determination of thorium

    USGS Publications Warehouse

    Grimaldi, F.S.; Fletcher, M.H.

    1956-01-01

    Thoron is commonly used for the spectrophotometric determination of thorium. An undesirable feature of its use is its high sensitivity to zirconium. This study describes the use of tartaric acid as a masking reagent for zirconium. Three tartaric acid-thoron systems, developed for the determination of thorium, differ with respect to the concentrations of thoron and tartaric acid. Mesotartaric acid, used in one of the systems, is most effective in masking zirconium. The behavior of rarer elements, usually associated with thorium ores, is determined in two systems, and a dilution method is described for the direct determination of thorium in monazite concentrates.

  13. Fatty acid composition of breast milk from three racial groups from Penang, Malaysia.

    PubMed

    Kneebone, G M; Kneebone, R; Gibson, R A

    1985-04-01

    The fatty acid composition of samples of breast milk obtained from 51 mothers (26 Malay, 15 Chinese, 10 Indian) residing in Penang, Malaysia was determined by gas chromatography. Despite living in close physical proximity the mothers from the three racial groups showed distinct cultural differences in dietary intake. These differences were reflected in differences in the fatty acid composition of breast milk samples. The milk of Chinese mothers was generally less saturated (41%) than that of Malay and Indian mothers (52 and 50% respectively). The milk of Chinese mothers was also richer in linoleic acid (17%) than that of Malay and Indian mothers (9% and 11% respectively). Overall the level of individual fatty acids fell within the range of values reported for Western mothers on well nourished diets and pointed to breast milk of high standard despite large variations in the diet of Malaysian mothers. PMID:3984928

  14. Fatty acid composition of breast milk from three racial groups from Penang, Malaysia.

    PubMed

    Kneebone, G M; Kneebone, R; Gibson, R A

    1985-04-01

    The fatty acid composition of samples of breast milk obtained from 51 mothers (26 Malay, 15 Chinese, 10 Indian) residing in Penang, Malaysia was determined by gas chromatography. Despite living in close physical proximity the mothers from the three racial groups showed distinct cultural differences in dietary intake. These differences were reflected in differences in the fatty acid composition of breast milk samples. The milk of Chinese mothers was generally less saturated (41%) than that of Malay and Indian mothers (52 and 50% respectively). The milk of Chinese mothers was also richer in linoleic acid (17%) than that of Malay and Indian mothers (9% and 11% respectively). Overall the level of individual fatty acids fell within the range of values reported for Western mothers on well nourished diets and pointed to breast milk of high standard despite large variations in the diet of Malaysian mothers.

  15. Arterial Blood Carbonic Acid Inversely Determines Lactic and Organic Acids

    PubMed Central

    Aiken, Christopher Geoffrey Alexander

    2013-01-01

    Objective: To establish that arterial blood carbonic acid varies inversely with lactic acid in accordance with bicarbonate exchanging for lactate across cell membranes through the anion exchange mechanism to maintain the Gibbs-Donnan equilibrium. Study Design: Over 5 years, lactate was measured on all blood gases taken from neonatal admissions, as well as organic acid whenever electrolytes were required. Results: Arterial blood gases from 63 infants given high calcium TPN were analyzed. Twenty two needed continuous positive airways pressure (CPAP) only and 31 intermittent positive pressure ventilation (IPPV) and surfactant followed by CPAP to treat respiratory distress syndrome in 51 and meconium aspiration syndrome in 2. All survived and were free of infection. Excluded gases were those with high and falling lactate soon after delivery representing perinatal asphyxia, and those on dexamethasone. Strong inverse relations between carbonic and lactic acids were found at all gestational ages and, independent of glomerular filtration, between carbonic and organic acids. Lactate (mmol/L) = 62.53 X PCO2 -0.96(mmHg) r2 0.315, n 1232, p <0.001. Sixty divided by PCO2 is a convenient measure of physiological lactate at any given PCO2. In the first week, 9.13 ± 2.57% of arterial gases from infants on IPPV had lactates above 120/PCO2, significantly more than 4.74 ± 2.73% on CPAP (p<0.05) and 2.47 ± 2.39% on no support. Conclusion: Changes in arterial blood carbonic acid cause immediate inverse changes in lactic acid, because their anions interchange across cell membranes according to the Gibbs –Donnan equilibrium. Increasing PCO2 from 40 to 120 mmHg decreased lactate from 1.5 mmol/L to 0.5 mmol/L, so that the sum of carbonic and lactic acids increased from 2.72 mmol/L to only 4.17 mmol/L. This helps explain the neuroprotective effect of hypercapnoea and highlights the importance of avoiding any degree of hypocapnoea in infants on IPPV. PMID:24392387

  16. Role of fatty acid composites in the toxicity of titanium dioxide nanoparticles used in cosmetic products.

    PubMed

    Chang, JuOae; Lee, Chang-Woo; Alsulimani, Helal Hussain; Choi, Jee Eun; Lee, Joo-Kyung; Kim, AhYoung; Park, Bae Ho; Kim, Jonghan; Lee, HeaYeon

    2016-01-01

    It has been recognized that the use of nanoparticles (NPs) in the cosmetic industry results in products with better efficacy and functionality. However, recent advances in molecular toxicology have revealed that NP exposure can promote cytotoxicity and oxidative damage, which has raised health concerns in the use of NPs in personal care products. Nevertheless, the mechanistic basis for the toxicity and safety of cosmetic NPs is poorly understood. The goal of the study was to determine the cytotoxicity and intracellular distribution of titanium dioxide (TiO2) NPs containing fatty acid composites (palmitoleic acid, palmitic acid, stearic acid and oleic acid) commonly used in cosmetic products. Two types of cells, human fibroblast skin cells and adenocarcinoma lung cells, were exposed to either bare TiO2 NPs or TiO2 NPs mixed with fatty acids for up to 48 hr. NMR analysis confirmed that the fatty acid composites remained in the NPs after wash. The cytotoxicity of TiO2 NPs was determined by cell viability measurement using quantitative confocal microscopy, and the localization of two different forms of TiO2 NPs were assessed using electron spectroscopic imaging with transmission electron microscopy. TiO2 NPs containing fatty acids posed significantly reduced cytotoxicity (80-88% decreases) than bare NPs in both cell types. Furthermore, there was less intracellular penetration of the NPs containing fatty acid composites compared with bare NPs. These results provide important insights into the role of fatty acids in protecting the cells from possible toxicity caused by NPs used in the production of cosmetic products.

  17. Role of fatty acid composites in the toxicity of titanium dioxide nanoparticles used in cosmetic products.

    PubMed

    Chang, JuOae; Lee, Chang-Woo; Alsulimani, Helal Hussain; Choi, Jee Eun; Lee, Joo-Kyung; Kim, AhYoung; Park, Bae Ho; Kim, Jonghan; Lee, HeaYeon

    2016-01-01

    It has been recognized that the use of nanoparticles (NPs) in the cosmetic industry results in products with better efficacy and functionality. However, recent advances in molecular toxicology have revealed that NP exposure can promote cytotoxicity and oxidative damage, which has raised health concerns in the use of NPs in personal care products. Nevertheless, the mechanistic basis for the toxicity and safety of cosmetic NPs is poorly understood. The goal of the study was to determine the cytotoxicity and intracellular distribution of titanium dioxide (TiO2) NPs containing fatty acid composites (palmitoleic acid, palmitic acid, stearic acid and oleic acid) commonly used in cosmetic products. Two types of cells, human fibroblast skin cells and adenocarcinoma lung cells, were exposed to either bare TiO2 NPs or TiO2 NPs mixed with fatty acids for up to 48 hr. NMR analysis confirmed that the fatty acid composites remained in the NPs after wash. The cytotoxicity of TiO2 NPs was determined by cell viability measurement using quantitative confocal microscopy, and the localization of two different forms of TiO2 NPs were assessed using electron spectroscopic imaging with transmission electron microscopy. TiO2 NPs containing fatty acids posed significantly reduced cytotoxicity (80-88% decreases) than bare NPs in both cell types. Furthermore, there was less intracellular penetration of the NPs containing fatty acid composites compared with bare NPs. These results provide important insights into the role of fatty acids in protecting the cells from possible toxicity caused by NPs used in the production of cosmetic products. PMID:27432239

  18. Method of preparing and using and composition for acidizing subterranean formations

    SciTech Connect

    Dill, W.R.

    1984-08-21

    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.

  19. Accurate determination of the amino acid content of selected feedstuffs.

    PubMed

    Rutherfurd, Shane M

    2009-01-01

    The accurate determination of the amino acid content is important. In the present study, a least-squares non-linear regression model of the amino acid content determined over multiple hydrolysis times was used to accurately determine the content of amino acids in five different feedstuffs. These values were compared with 24-h hydrolysis values determined for the same feedstuffs. Overall, approximately two-thirds of the amino acids determined in this study (aspartic acid, threonine, glutamic acid, proline, glycine, alanine, leucine, tyrosine, phenylalanine and arginine) using 24-h hydrolysis were in good agreement (<3% difference). When examined across feedstuffs, the concentration of serine was underestimated by the 24-h hydrolysis method by 4.8%, while the concentrations of histidine and lysine were overestimated by 3.9% and 3.1%, respectively.

  20. [Determination of glutamic acid in biological material by capillary electrophoresis].

    PubMed

    Narezhnaya, E; Krukier, I; Avrutskaya, V; Degtyareva, A; Igumnova, E A

    2015-01-01

    The conditions for the identification and determination of Glutamic acid by capillary zone electrophoresis without their preliminary derivatization have been optimized. The effect of concentration of buffer electrolyte and pH on determination of Glutamic acid has been investigated. It is shown that the 5 Mm borate buffer concentration and a pH 9.15 are optimal. Quantitative determination of glutamic acid has been carried out using a linear dependence between the concentration of the analyte and the area of the peak. The accuracy and reproducibility of the determination are confirmed by the method "introduced - found". Glutamic acid has been determined in the placenta homogenate. The duration of analysis doesn't exceed 30 minutes. The results showed a decrease in the level of glutamic acid in cases of pregnancy complicated by placental insufficiency compared with the physiological, and this fact allows to consider the level of glutamic acid as a possible marker of complicated pregnancy.

  1. The effects of season on fatty acid composition and ω3/ω6 ratios of northern pike ( Esox lucius L., 1758) muscle lipids

    NASA Astrophysics Data System (ADS)

    Mert, Ramazan; Bulut, Sait; Konuk, Muhsin

    2015-01-01

    In the present study, the effects of season on fatty acid composition, total lipids, and ω3/ω6 ratios of northern pike muscle lipids in Kizilirmak River (Kirikkale, Turkey) were investigated. A total of 35 different fatty acids were determined in gas chromatography. Among these, palmitic, oleic, and palmitoleic acids had the highest proportion. The main polyunsaturated fatty acids (PUFAs) were found to be docosahexaenoic acid, eicosapentaenoic acid, and arachidonic acid. There were more PUFAs than monounsaturated fatty acids (MUFA) in all seasons. Similarly, the percentages of ω3 fatty acids were higher than those of total ω6 fatty acids in the fatty acid composition. ω3/ω6 ratios were calculated as 1.53, 1.32, 1.97, and 1.71 in spring, summer, autumn and winter, respectively. Overall, we found that the fatty acid composition and ω3/ω6 fatty acid ratio in the muscle of northern pike were significantly influenced by season.

  2. Amino acid composition, score and in vitro protein digestibility of foods commonly consumed in northwest Mexico.

    PubMed

    Caire-Juvera, Graciela; Vázquez-Ortiz, Francisco A; Grijalva-Haro, Maria I

    2013-01-01

    A better knowledge of the amino acid composition of foods commonly consumed in different regions is essential to calculate their scores and, therefore, to predict their protein quality. This paper presents the amino acid composition, amino acid score and in vitro protein digestibility of fifteen foods that are commonly consumed in Northwest Mexico. The foods were prepared by the traditional methods and were analyzed by reverse-phase HPLC. The chemical score for each food was determined using the recommendations for children of 1-2 years of age, and the digestibility was evaluated using a multienzyme technique. Lysine was the limiting amino acid in cereal-based products (scores 15 to 54), and methionine and cysteine were limiting in legume products (scores 41 to 47), boiled beef (score = 75) and hamburger (score = 82). The method of preparation had an effect on the content of certain amino acids, some of them increased and others decreased their content. Meat products and regional cheese provided a high amino acid score (scores 67 to 91) and digestibility (80.7 to 87.8%). Bologna, a processed meat product, had a lower digestibility (75.4%). Data on the amino acid composition of foods commonly consumed in Mexico can be used to provide valuable information on food analysis and protein quality, and to contribute to nutrition and health research and health programs.

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

    PubMed

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

    2015-03-15

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

  4. Site specific incorporation of heavy atom-containing unnatural amino acids into proteins for structure determination

    DOEpatents

    Xie, Jianming; Wang, Lei; Wu, Ning; Schultz, Peter G.

    2008-07-15

    Translation systems and other compositions including orthogonal aminoacyl tRNA-synthetases that preferentially charge an orthogonal tRNA with an iodinated or brominated amino acid are provided. Nucleic acids encoding such synthetases are also described, as are methods and kits for producing proteins including heavy atom-containing amino acids, e.g., brominated or iodinated amino acids. Methods of determining the structure of a protein, e.g., a protein into which a heavy atom has been site-specifically incorporated through use of an orthogonal tRNA/aminoacyl tRNA-synthetase pair, are also described.

  5. Meteoritic Amino Acids: Diversity in Compositions Reflects Parent Body Histories

    PubMed Central

    2016-01-01

    The analysis of amino acids in meteorites dates back over 50 years; however, it is only in recent years that research has expanded beyond investigations of a narrow set of meteorite groups (exemplified by the Murchison meteorite) into meteorites of other types and classes. These new studies have shown a wide diversity in the abundance and distribution of amino acids across carbonaceous chondrite groups, highlighting the role of parent body processes and composition in the creation, preservation, or alteration of amino acids. Although most chiral amino acids are racemic in meteorites, the enantiomeric distribution of some amino acids, particularly of the nonprotein amino acid isovaline, has also been shown to vary both within certain meteorites and across carbonaceous meteorite groups. Large l-enantiomeric excesses of some extraterrestrial protein amino acids (up to ∼60%) have also been observed in rare cases and point to nonbiological enantiomeric enrichment processes prior to the emergence of life. In this Outlook, we review these recent meteoritic analyses, focusing on variations in abundance, structural distributions, and enantiomeric distributions of amino acids and discussing possible explanations for these observations and the potential for future work. PMID:27413780

  6. Meteoritic Amino Acids: Diversity in Compositions Reflects Parent Body Histories.

    PubMed

    Elsila, Jamie E; Aponte, José C; Blackmond, Donna G; Burton, Aaron S; Dworkin, Jason P; Glavin, Daniel P

    2016-06-22

    The analysis of amino acids in meteorites dates back over 50 years; however, it is only in recent years that research has expanded beyond investigations of a narrow set of meteorite groups (exemplified by the Murchison meteorite) into meteorites of other types and classes. These new studies have shown a wide diversity in the abundance and distribution of amino acids across carbonaceous chondrite groups, highlighting the role of parent body processes and composition in the creation, preservation, or alteration of amino acids. Although most chiral amino acids are racemic in meteorites, the enantiomeric distribution of some amino acids, particularly of the nonprotein amino acid isovaline, has also been shown to vary both within certain meteorites and across carbonaceous meteorite groups. Large l-enantiomeric excesses of some extraterrestrial protein amino acids (up to ∼60%) have also been observed in rare cases and point to nonbiological enantiomeric enrichment processes prior to the emergence of life. In this Outlook, we review these recent meteoritic analyses, focusing on variations in abundance, structural distributions, and enantiomeric distributions of amino acids and discussing possible explanations for these observations and the potential for future work. PMID:27413780

  7. Meteoritic Amino Acids: Diversity in Compositions Reflects Parent Body Histories.

    PubMed

    Elsila, Jamie E; Aponte, José C; Blackmond, Donna G; Burton, Aaron S; Dworkin, Jason P; Glavin, Daniel P

    2016-06-22

    The analysis of amino acids in meteorites dates back over 50 years; however, it is only in recent years that research has expanded beyond investigations of a narrow set of meteorite groups (exemplified by the Murchison meteorite) into meteorites of other types and classes. These new studies have shown a wide diversity in the abundance and distribution of amino acids across carbonaceous chondrite groups, highlighting the role of parent body processes and composition in the creation, preservation, or alteration of amino acids. Although most chiral amino acids are racemic in meteorites, the enantiomeric distribution of some amino acids, particularly of the nonprotein amino acid isovaline, has also been shown to vary both within certain meteorites and across carbonaceous meteorite groups. Large l-enantiomeric excesses of some extraterrestrial protein amino acids (up to ∼60%) have also been observed in rare cases and point to nonbiological enantiomeric enrichment processes prior to the emergence of life. In this Outlook, we review these recent meteoritic analyses, focusing on variations in abundance, structural distributions, and enantiomeric distributions of amino acids and discussing possible explanations for these observations and the potential for future work.

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

    NASA Astrophysics Data System (ADS)

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

    2013-11-01

    Amino acids (AAs) comprise a large fraction of organic nitrogen (N) in plankton and sedimenting matter. Aquatic studies of organic N compounds in general and of AAs in particular, mostly concentrate on marine environments. In order to study the cycling and fate of organic N and AAs in lakes, we measured the N isotopic composition (δ15N) 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 δ15N-AA patterns found for the sediment trap material were consistent with published δ15N-AA data for marine plankton. The AA composition and primary δ15N-AA signatures are preserved until burial in the sediments. During early sedimentary diagenesis, the δ15N values of single AAs appear to increase, exceeding those of the bulk OM. This increase in δ15N-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 δ15N-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 δ15N-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 δ15N-AAs and average source δ15N-AAs was sensitive to the trophic states of the two lakes. A proxy for total heterotrophic AA re-synthesis (ΣV), which is strongly associated with heterotrophic microbial reworking of the OM, was calculated based on δ15N values of trophic AAs. Higher ΣV in Lake Brienz indicate enhanced

  9. Comparison of fatty acid composition of cell homogenates and isolated chloroplasts in Acetabularia crenulata (Lamouroux).

    PubMed

    Santiago-Vázquez, Lory Z; Jacobs, Robert S

    2005-01-01

    Algal preparations from Acetabularia crenulata were analyzed for their fatty acid composition to establish the suitability of this alga as a model to study fatty acid oxidation and oxylipin biosynthesis. The work was based on two goals. The first goal of this study was to determine the contribution of fatty acids from contaminating bacteria and how this influenced the total fatty acid composition of cell homogenates of A. crenulata collected in the wild as compared to specimens cultured in sterile conditions. The major fatty acids detected for both specimens were palmitic (C16:0), palmitoleic (C16:1n-7), oleic (C18:1n-9), linoleic (C18:2n-6), linolenic (C18:3n-3), and octadecatetraenoic acid (C18:4n-3). Significant amounts of odd-chain fatty acids common to bacteria were not detected in either sample. Furthermore, branched-chain fatty acids, typical bacterial biomarkers, were not detected in either sample. Data suggest that bacteria do not greatly contribute to the total fatty acid pool of A. crenulata. The second goal was to compare the fatty acid composition of cell homogenates with that of isolated chloroplasts. Comparatively speaking palmitoleic and octadecatetraenoic acid were found at significantly lower concentrations in the chloroplast whereas oleic and linolenic acid were found at significantly higher amounts in this organelle. Furthermore, the amount of hexadecatrienoic acid (C16:3), a fatty acid commonly esterified to monogalactosyldiacylglycerol (MGDG; lipid present at high concentrations inside the chloroplasts of algae), was present at very low concentrations in these plastids (0.7%). Typically green algal follow the "prokaryotic pathway" for MGDG biosynthesis where C18:3 is esterified at the sn-1 position of the glycerol backbone and C18:3 or C16:3 at the sn-2 position, making C16:3 a major fatty acid inside chloroplasts. Interestingly, our results suggest that chloroplasts of A. crenulata appear to follow the "eukaryotic pathway" for MGDG

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

    PubMed Central

    Derr, Julien; Manapat, Michael L.; Rajamani, Sudha; Leu, Kevin; Xulvi-Brunet, Ramon; Joseph, Isaac; Nowak, Martin A.; Chen, Irene A.

    2012-01-01

    During the origin of life, the biological information of nucleic acid polymers must have increased to encode functional molecules (the RNA world). Ribozymes tend to be compositionally unbiased, as is the vast majority of possible sequence space. However, ribonucleotides vary greatly in synthetic yield, reactivity and degradation rate, and their non-enzymatic polymerization results in compositionally biased sequences. While natural selection could lead to complex sequences, molecules with some activity are required to begin this process. Was the emergence of compositionally diverse sequences a matter of chance, or could prebiotically plausible reactions counter chemical biases to increase the probability of finding a ribozyme? Our in silico simulations using a two-letter alphabet show that template-directed ligation and high concatenation rates counter compositional bias and shift the pool toward longer sequences, permitting greater exploration of sequence space and stable folding. We verified experimentally that unbiased DNA sequences are more efficient templates for ligation, thus increasing the compositional diversity of the pool. Our work suggests that prebiotically plausible chemical mechanisms of nucleic acid polymerization and ligation could predispose toward a diverse pool of longer, potentially structured molecules. Such mechanisms could have set the stage for the appearance of functional activity very early in the emergence of life. PMID:22319215

  11. Nitric acid uptake by sulfuric acid solutions under stratospheric conditions - Determination of Henry's Law solubility

    NASA Technical Reports Server (NTRS)

    Reihs, Christa M.; Golden, David M.; Tolbert, Margaret A.

    1990-01-01

    The uptake of nitric acid by sulfuric acid solutions representative of stratospheric particulate at low temperatures was measured to determine the solubility of nitric acid in sulfuric acid solutions as a function of H2SO4 concentration and solution temperature. Solubilities are reported for sulfuric acid solutions ranging from 58 to 87 wt pct H2SO4 over a temperature range from 188 to 240 K, showing that, in general, the solubility of nitric acid increases with decreasing sulfuric acid concentration and with decreasing temperature. The measured solubilities indicate that nitric acid in the global stratosphere will be found predominantly in the gas phase.

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

    NASA Technical Reports Server (NTRS)

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

    1993-01-01

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

  13. Cultural characteristics and fatty acid composition of Corynebacterium acnes.

    PubMed

    Moss, C W; Dowell, V R; Lewis, V J; Schekter, M A

    1967-11-01

    A detailed study of the cultural characteristics and cellular fatty acid composition of 27 isolates of Corynebacterium acnes was performed to establish the properties by which this organism may be identified and characterized. The fatty acids were extracted directly from whole cells and examined as methyl esters by gas-liquid chromatography. Each strain possessed a similar fatty acid profile which was characterized by a large percentage of C15 branched-chain acid. Uniformity in certain biochemical reactions and cultural characteristics was also observed. All strains were catalase-positive, nonmotile, and urease-negative, reduced nitrate, liquefied gelatin, failed to hydrolyze esculin and starch, and gave a positive methyl red test. Glucose, fructose, and glycerol were fermented, but not lactose, salicin, sucrose, maltose, xylose, or arabinose. Production of hydrogen sulfide and indole, fermentation of mannitol, and hemolytic activity were variable characteristics. Two species of the genus Propionibacterium were also tested and found to be similar to C. acnes both in cultural characteristics and fatty acid composition. The results strengthen previous suggestions that C. acnes should be classified in the genus Propionibacterium.

  14. Thermodynamics of mixed micelles: Determination of the aggregate composition.

    PubMed

    Letellier, Pierre; Mayaffre, Alain; Turmine, Mireille

    2008-11-01

    In most studies concerning surfactant mixtures, the determination of the composition of mixed micelles is often tricky. This composition can be obtained by different ways. One of them, undoubtedly the most used, supposes, a priori, that the surfactant in the micelle follows the regular solution model. This poses a problem on the thermodynamic point of view because in these studies, a model of behavior is first admitted for deducing a composition. In a correct thermodynamic approach, a composition should first be determined and then, a model of behavior which accounts for the observed physicochemical properties can be found. This approach is all the more questionable since the application of the Gibbs-Duhem relationship to the pseudo-phase allows aggregate composition to be determined simply, without using a solution model, because the composition of the bulk at the threshold of aggregation is known. In this article, we describe and validate a simple procedure, which supplements that proposed by Rodenas et al. [E. Rodenas, M. Valiente, M.D. Villafruela, J. Phys. Chem. B 103 (1999) 4549], and which allows determination of the activities of the components of the micellar aggregate and its composition. The results are compared to those obtained with other approaches such as molecular-thermodynamic model. PMID:18723182

  15. Fatty acid composition and possible health effects of coconut constituents.

    PubMed

    Pehowich, D J; Gomes, A V; Barnes, J A

    2000-06-01

    The link between excessive consumption of dietary saturated fats and coronary heart disease (CHD) is now well established. Because of its high content of saturated fatty acids, the consumption of foods containing coconut oil may therefore be a risk factor for CHD. While the fatty acid composition of coconut oil is well established, relatively little is known about the other constituents of coconut: the milk, water, cream and meat fractions. In this study, we show that while the water fraction is low in lipid content, the milk contains about 24% of the fat content of oil and the cream and meat fractions about 34%. The other coconut constituents contain significant amounts of medium-chain triglycerides that are formed from fatty acids of chain length 8:0 to 14:0. It is these fatty acids, primarily 14:0, that are thought to be atherogenic. On the other hand, medium-chain triglycerides may be advantageous under some circumstances in that they are absorbed intact and do not undergo degradation and re-esterification processes. As a result, medium-chain triglycerides provide a ready source of energy and may be useful in baby foods or in diet therapy. Nevertheless, the possible negative effects of the saturated fatty acids and the absence of the essential fatty acid linolenic acid from all coconut constituents suggest that the coconut milk, oil and cream should not be used on a regular basis in adults. PMID:10948851

  16. Fatty acid composition and possible health effects of coconut constituents.

    PubMed

    Pehowich, D J; Gomes, A V; Barnes, J A

    2000-06-01

    The link between excessive consumption of dietary saturated fats and coronary heart disease (CHD) is now well established. Because of its high content of saturated fatty acids, the consumption of foods containing coconut oil may therefore be a risk factor for CHD. While the fatty acid composition of coconut oil is well established, relatively little is known about the other constituents of coconut: the milk, water, cream and meat fractions. In this study, we show that while the water fraction is low in lipid content, the milk contains about 24% of the fat content of oil and the cream and meat fractions about 34%. The other coconut constituents contain significant amounts of medium-chain triglycerides that are formed from fatty acids of chain length 8:0 to 14:0. It is these fatty acids, primarily 14:0, that are thought to be atherogenic. On the other hand, medium-chain triglycerides may be advantageous under some circumstances in that they are absorbed intact and do not undergo degradation and re-esterification processes. As a result, medium-chain triglycerides provide a ready source of energy and may be useful in baby foods or in diet therapy. Nevertheless, the possible negative effects of the saturated fatty acids and the absence of the essential fatty acid linolenic acid from all coconut constituents suggest that the coconut milk, oil and cream should not be used on a regular basis in adults.

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

    PubMed

    Mark, Harker; Harding, Clive R

    2013-04-01

    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).

  18. Amino Acid compositions of 27 food fishes and their importance in clinical nutrition.

    PubMed

    Mohanty, Bimal; Mahanty, Arabinda; Ganguly, Satabdi; Sankar, T V; Chakraborty, Kajal; Rangasamy, Anandan; Paul, Baidyanath; Sarma, Debajit; Mathew, Suseela; Asha, Kurukkan Kunnath; Behera, Bijay; Aftabuddin, Md; Debnath, Dipesh; Vijayagopal, P; Sridhar, N; Akhtar, M S; Sahi, Neetu; Mitra, Tandrima; Banerjee, Sudeshna; Paria, Prasenjit; Das, Debajeet; Das, Pushpita; Vijayan, K K; Laxmanan, P T; Sharma, A P

    2014-01-01

    Proteins and amino acids are important biomolecules which regulate key metabolic pathways and serve as precursors for synthesis of biologically important substances; moreover, amino acids are building blocks of proteins. Fish is an important dietary source of quality animal proteins and amino acids and play important role in human nutrition. In the present investigation, crude protein content and amino acid compositions of important food fishes from different habitats have been studied. Crude protein content was determined by Kjeldahl method and amino acid composition was analyzed by high performance liquid chromatography and information on 27 food fishes was generated. The analysis showed that the cold water species are rich in lysine and aspartic acid, marine fishes in leucine, small indigenous fishes in histidine, and the carps and catfishes in glutamic acid and glycine. The enriched nutrition knowledge base would enhance the utility of fish as a source of quality animal proteins and amino acids and aid in their inclusion in dietary counseling and patient guidance for specific nutritional needs.

  19. Amino Acid Compositions of 27 Food Fishes and Their Importance in Clinical Nutrition

    PubMed Central

    Mahanty, Arabinda; Sankar, T. V.; Chakraborty, Kajal; Rangasamy, Anandan; Paul, Baidyanath; Sarma, Debajit; Mathew, Suseela; Asha, Kurukkan Kunnath; Behera, Bijay; Aftabuddin, Md.; Debnath, Dipesh; Vijayagopal, P.; Sridhar, N.; Akhtar, M. S.; Sahi, Neetu; Mitra, Tandrima; Banerjee, Sudeshna; Das, Debajeet; Das, Pushpita; Vijayan, K. K.; Laxmanan, P. T.; Sharma, A. P.

    2014-01-01

    Proteins and amino acids are important biomolecules which regulate key metabolic pathways and serve as precursors for synthesis of biologically important substances; moreover, amino acids are building blocks of proteins. Fish is an important dietary source of quality animal proteins and amino acids and play important role in human nutrition. In the present investigation, crude protein content and amino acid compositions of important food fishes from different habitats have been studied. Crude protein content was determined by Kjeldahl method and amino acid composition was analyzed by high performance liquid chromatography and information on 27 food fishes was generated. The analysis showed that the cold water species are rich in lysine and aspartic acid, marine fishes in leucine, small indigenous fishes in histidine, and the carps and catfishes in glutamic acid and glycine. The enriched nutrition knowledge base would enhance the utility of fish as a source of quality animal proteins and amino acids and aid in their inclusion in dietary counseling and patient guidance for specific nutritional needs. PMID:25379285

  20. Determination of the presence of hyaluronic acid in preparations containing amino acids: the molecular weight characterization.

    PubMed

    Bellomaria, A; Nepravishta, R; Mazzanti, U; Marchetti, M; Piccioli, P; Paci, M

    2014-10-15

    Several pharmaceutical preparations contain hyaluronic acid in the presence of a large variety of low molecular weight charged molecules like amino acids. In these mixtures, it is particularly difficult to determine the concentration and the molecular weight of the hyaluronic acid fragments. In fact zwitterionic compounds in high concentration behave by masking the hyaluronic acid due to the electrostatic interactions between amino acids and hyaluronic acid. In such conditions the common colorimetric test of the hyaluronic acid determination appears ineffective and in the (1)H NMR spectra the peaks of the polymer disappear completely. By a simple separation procedure the presence of hyaluronic acid was revealed by the DMAB test and (1)H NMR while its average molecular weight in the final product was determined by DOSY NMR spectroscopy alone. The latter determination is very important due to the healthy effects of some sizes of this polymer's fragments. PMID:25078662

  1. Protein Crowding Is a Determinant of Lipid Droplet Protein Composition.

    PubMed

    Kory, Nora; Thiam, Abdou-Rachid; Farese, Robert V; Walther, Tobias C

    2015-08-10

    Lipid droplets (LDs) are lipid storage organelles that grow or shrink, depending on the availability of metabolic energy. Proteins recruited to LDs mediate many metabolic functions, including phosphatidylcholine and triglyceride synthesis. How the LD protein composition is tuned to the supply and demand for lipids remains unclear. We show that LDs, in contrast to other organelles, have limited capacity for protein binding. Consequently, macromolecular crowding plays a major role in determining LD protein composition. During lipolysis, when LDs and their surfaces shrink, some, but not all, proteins become displaced. In vitro studies show that macromolecular crowding, rather than changes in monolayer lipid composition, causes proteins to fall off the LD surface. As predicted by a crowding model, proteins compete for binding to the surfaces of LDs. Moreover, the LD binding affinity determines protein localization during lipolysis. Our findings identify protein crowding as an important principle in determining LD protein composition. PMID:26212136

  2. Effect of the fatty acid composition of acclimated oenological Lactobacillus plantarum on the resistance to ethanol.

    PubMed

    Bravo-Ferrada, B M; Gómez-Zavaglia, A; Semorile, L; Tymczyszyn, E E

    2015-02-01

    The aim of this work was to evaluate the changes due to acclimation to ethanol on the fatty acid composition of three oenological Lactobacillus plantarum strains and their effect on the resistance to ethanol and malic acid consumption (MAC). Lactobacillus plantarum UNQLp 133, UNQLp 65.3 and UNQLp 155 were acclimated in the presence of 6 or 10% v/v ethanol, for 48 h at 28°C. Lipids were extracted to obtain fatty acid methyl esters and analysed by gas chromatography interfaced with mass spectroscopy. The influence of change in fatty acid composition on the viability and MAC in synthetic wine was analysed by determining the Pearson correlation coefficient. Acclimated strains showed a significant change in the fatty composition with regard to the nonacclimated strains. Adaptation to ethanol led to a decrease in the unsaturated/saturated ratio, mainly resulting from an increase in the contribution of short-length fatty acid C12:0 and a decrease of C18:1. The content of C12:0 was related to a higher viability after inoculation of synthetic wine. The MAC increased at higher contents in saturated fatty acid, but its efficiency was strain dependent.

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

    NASA Astrophysics Data System (ADS)

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

    2010-10-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2014-11-01

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

  5. Determination of fumaric acid, maleic acid, and phthalic acid in groundwater and soil

    SciTech Connect

    Dietz, E.A.; Singley, K.F. . Technology Center)

    1994-01-01

    When present at > 1 [mu]g/mL, each title compound was determined in groundwater by ion-exclusion chromatography after sample acidification and filtration. For groundwater with one or all analyte concentrations of < 1 [mu]g/mL, the acid anions were first concentrated from a 100-mL sample using a quaternary amine anion-exchange cartridge. The acids were recovered by eluting the cartridge with 1 mL of N H[sub 2]SO[sub 4] and 2-mL deionized water washes; this solution then was examined by anion-exclusion chromatography. Analytes were monitored with a UV detector operated at 200 nm. The analysis procedures for groundwater were validated with solutions which were fortified with from 50 ng/mL to 200 [mu]g/mL of each analyte; recoveries ranged from 90 to 110%. The soil method was validated using fortified samples which contained each acid at concentrations of from 5 to 160 [mu]g/g. Recovery values were between 81 and 120%. For samples exhibiting minimal detector response from compounds other than the acids of interest, 100-[mu]L injection volumes provided an estimated detection limit of 1 [mu]g/g for soil and 10 ng/mL for groundwater.

  6. Possible effects of diagenesis on the stable isotope composition of amino acids in carbonaceous meteorites

    NASA Astrophysics Data System (ADS)

    Engel, Michael H.

    2015-09-01

    The initial report of indigenous, non-racemic protein amino acids (L-enantiomer excess) in the Murchison meteorite was based on the fact that only eight of the twenty amino acids characteristic of all life on Earth was present in this stone1. The absence of the other protein amino acids indicated that contamination subsequent to impact was highly unlikely. The development of new techniques for determining the stable isotope composition of individual amino acid enantiomers in the Murchison meteorite further documented the extraterrestrial origins of these compounds2,3. The stable isotope approach continues to be used to document the occurrence of an extraterrestrial L-enantiomer excess of protein amino acids in other carbonaceous meteorites4. It has been suggested that this L-enantiomer excess may result from aqueous reprocessing on meteorite parent bodies4,5. Preliminary results of simulation experiments are presented that are used to determine the extent to which the stable isotope compositions of amino acid constituents of carbonaceous meteorites may have been altered by these types of diagenetic processes subsequent to synthesis.

  7. Effects of roasting temperature and duration on fatty acid composition, phenolic composition, Maillard reaction degree and antioxidant attribute of almond (Prunus dulcis) kernel.

    PubMed

    Lin, Jau-Tien; Liu, Shih-Chun; Hu, Chao-Chin; Shyu, Yung-Shin; Hsu, Chia-Ying; Yang, Deng-Jye

    2016-01-01

    Roasting treatment increased levels of unsaturated fatty acids (linoleic, oleic and elaidic acids) as well as saturated fatty acids (palmitic and stearic acids) in almond (Prunus dulcis) kernel oils with temperature (150 or 180 °C) and duration (5, 10 or 20 min). Nonetheless, higher temperature (200 °C) and longer duration (10 or 20 min) roasting might result in breakdown of fatty acids especially for unsaturated fatty acids. Phenolic components (total phenols, flavonoids, condensed tannins and phenolic acids) of almond kernels substantially lost in the initial phase; afterward these components gradually increased with roasting temperature and duration. Similar results also observed for their antioxidant activities (scavenging DPPH and ABTS(+) radicals and ferric reducing power). The changes of phenolic acid and flavonoid compositions were also determined by HPLC. Maillard reaction products (estimated with non-enzymatic browning index) also increased with roasting temperature and duration; they might also contribute to enhancing the antioxidant attributes.

  8. Effects of roasting temperature and duration on fatty acid composition, phenolic composition, Maillard reaction degree and antioxidant attribute of almond (Prunus dulcis) kernel.

    PubMed

    Lin, Jau-Tien; Liu, Shih-Chun; Hu, Chao-Chin; Shyu, Yung-Shin; Hsu, Chia-Ying; Yang, Deng-Jye

    2016-01-01

    Roasting treatment increased levels of unsaturated fatty acids (linoleic, oleic and elaidic acids) as well as saturated fatty acids (palmitic and stearic acids) in almond (Prunus dulcis) kernel oils with temperature (150 or 180 °C) and duration (5, 10 or 20 min). Nonetheless, higher temperature (200 °C) and longer duration (10 or 20 min) roasting might result in breakdown of fatty acids especially for unsaturated fatty acids. Phenolic components (total phenols, flavonoids, condensed tannins and phenolic acids) of almond kernels substantially lost in the initial phase; afterward these components gradually increased with roasting temperature and duration. Similar results also observed for their antioxidant activities (scavenging DPPH and ABTS(+) radicals and ferric reducing power). The changes of phenolic acid and flavonoid compositions were also determined by HPLC. Maillard reaction products (estimated with non-enzymatic browning index) also increased with roasting temperature and duration; they might also contribute to enhancing the antioxidant attributes. PMID:26213005

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

    PubMed

    Thambugala, Dinushika; Cloutier, Sylvie

    2014-11-01

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

  10. Determination of optimum electrolyte composition for molten carbonate fuel cells

    SciTech Connect

    Yuh, C.Y.; Pigeaud, A.

    1987-01-01

    The objective of this study is to determine the optimum electrolyte composition for molten carbonate fuel cells. To accomplish this, the contractor will provide: (1) Comprehensive reports of on-going efforts to optimize carbonate composition. (2) A list of characteristics affected by electrolyte composition variations (e.g. ionic conductivity, vapor pressure, melting range, gas solubility, exchange current densities on NiO, corrosion and cathode dissolution effects). (3) Assessment of the overall effects that these characteristics have on state-of-the-art cell voltage and lifetime.

  11. Determination of optimum electrolyte composition for molten carbonate fuel cells

    SciTech Connect

    Yuh, C.Y.; Pigeaud, A.

    1988-03-01

    The objective of this study is to determine the optimum electrolyte composition for molten carbonate fuel cells. To accomplish this, the contractor will provide: (1) Comprehensive reports of on-going efforts to optimize carbonate composition. (2) A list of characteristics affected by electrolyte composition variations (e.g. ionic conductivity, vapor pressure, melting range, gas solubility, exchange current densities on NiO, corrosion and cathode dissolution effects). (3) Assessment of the overall effects that these characteristics have on state-of-the-art cell voltage and lifetime.

  12. Determination of optimum electrolyte composition for molten carbonate fuel cells

    SciTech Connect

    Yuh, C.Y.; Pigeaud, A.

    1987-01-01

    The objective of this study is to determine the optimum electrolyte composition for molten carbonate fuel cells. To accomplish this, the contractor will provide: (1) Comprehensive reports of on-going efforts to optimize carbonate composition. (2) A list of characteristics affected by electrolyte composition variations (e.g. ionic conductivity, vapor pressure, melting range, gas solubility, exchange current densities on NiO, corrosion and cathode dissolution effects). (3) Assessment of the overall effects that these characteristics have state-of-the-art cell voltage and lifetime.

  13. Determination of optimum electrolyte composition for molten carbonate fuel cells

    SciTech Connect

    Yuh, C.Y.; Pigeaud, A.

    1988-06-01

    The objective of this study is to determine the optimum electrolyte composition for molten carbonate fuel cells. To accomplish this, the contractor will provide: (1) Comprehensive reports of on-going efforts to optimize carbonate composition. (2) A list of characteristics affected by electrolyte composition variations (e.g. ionic conductivity, vapor pressure, melting range, gas solubility, exchange current densities on NiO, corrosion and cathode dissolution effects). (3) Assessment of the overall effects that these characteristics have on state-of-the-art cell voltage and lifetime.

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

    PubMed

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

    2014-12-01

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

  15. A color-determining amino acid residue of proteorhodopsin.

    PubMed

    Ozaki, Yuya; Kawashima, Takayoshi; Abe-Yoshizumi, Rei; Kandori, Hideki

    2014-09-30

    Proteorhodopsin (PR) is a light-driven proton pump found in marine bacteria. More than 1000 PRs are classified as blue-absorbing (λmax ∼ 490 nm) and green-absorbing (λmax ∼ 525 nm) PRs. The color determinant is known to be at position 105, where blue-absorbing and green-absorbing PRs possess Gln and Leu, respectively. This suggests hydrophobicity at position 105 plays a key role in color tuning. Here we successfully introduced 19 amino acid residues into position 105 of green-absorbing PR in the membrane environment and investigated the absorption properties. High-performance liquid chromatography analysis shows that the isomeric composition of the all-trans form is >70% for all mutants, indicating little influence of different isomers on color tuning. Absorption spectra of the wild-type and 19 mutant proteins were well-characterized by the pH-dependent equilibria of the protonated and deprotonated counterion (Asp97) of the Schiff base, whereas the λmax values of these two states and the pKa value differed significantly among mutants. Although Gln and Leu are hydrophilic and hydrophobic residues, respectively, the λmax values of the two states and the pKa value did not correlate with the hydropathy index of residues. In contrast, the λmax and pKa were correlated with the volume of residues, though Gln and Leu possess similar volumes. This observation concludes that the λmax and pKa of Asp97 are determined by local and specific interactions in the Schiff base moiety, in which the volume of the residue at position 105 is more influential than its hydrophobicity. We suggest that the hydrogen-bonding network in the Schiff base moiety plays a key role in the λmax and pKa of Asp97, and the hydrogen-bonding network is significantly perturbed by large amino acid residues but may be preserved by additional water molecule(s) for small amino acid residues at position 105. PMID:25180875

  16. Feeding oleamide to lactating Jersey cows 1. Effects on lactation performance and milk fatty acid composition.

    PubMed

    Jenkins, T C

    2000-02-01

    Oleamide was previously reported to resist ruminal biohydrogenation and elevate milk oleic acid concentration when fed to lactating Holstein cows. To determine if Jersey cows responded similarly to oleamide, four lactating Jersey cows (mean 417 kg of body weight and 64 days in milk) were fed four diets in a 4x4 Latin square with 2-wk periods. Diets were total mixed ration containing 47% corn silage and 53% concentrate (dry matter basis) and were supplemented with no added fat (control), or with 3.5% added fat from either higholeic canola oil, a commercial source of oleamide, or oleamide synthesized from oleic acid and urea. The canola oil supplement had no effect on milk yield or composition. Compared to canola oil, the oleamide supplements reduced milk yield, dry matter intake, and milk fat and protein contents. Milk oleic acid concentration increased from 17.4% of total fatty acids for the control diet to 22.1% for the canola oil diet. Both oleamides further increased milk oleic acid to 30.0 and 27.1% of total fatty acids for the commercial and synthesized oleamides, respectively. Milk palmitic acid was reduced and stearic acid was increased by all fat supplements but more so by the oleamides than by the canola oil. Consistent with previous reports that fatty acyl amides resist ruminal biohydrogenation, feeding oleamide to Jersey cows in this study increased milk oleic acid concentration but had negative effects on feed intake and milk yield.

  17. Simultaneous determination of equivalence volumes and acid dissociation constants from potentiometric titration data.

    PubMed

    Papanastasiou, G; Ziogas, I

    1995-06-01

    New iterative methods for analysis of potentiometric titration data of (a) mixtures of weak monoprotic acids with their conjugate bases, (b) solutions of polyprotic (di- and triprotic) acids, and (c) mixtures of two diprotic acids are presented. These methods, using data exclusively resulting from the acidic region of the titration curve permits the accurate determination of the analytical concentration of one or more acids even if the titration is stopped well before the end point of the titration. For the titration of a solution containing a conjugate acid/base pair, the proposed procedure enables the extraction of the initial composition of the mixture, as well as the dissociation constant of the concerned acid. Thus, it is possible by this type of analysis to distinguish whether a weak acid has been contaminated by a strong base and define the extent of the contamination. On the other hand, for the titration of polyprotic acids, the proposed approach enables the extraction of the accurate values of the equivalence volume and the dissociation constants K(i) even when the ionization stages overlap. Finally, for the titration of a mixture of two diprotic acids the proposed procedure enables the determination of the composition of the mixture even if the sum of the concentrations of the acids is not known. This method can be used in the analysis of solutions containing two diastereoisomeric forms of a weak diprotic acid. The test of the proposed procedures by means of ideal and Monte Carlo simulated data revealed that these methods are fairly applicable even when the titration data are considerably obscured by 'noise' or contain an important systematic error. The proposed procedures were also successfully applied to experimental titration data.

  18. Screening of the entire USDA castor germplasm collection for oil content and fatty acid composition for optimum biodiesel production.

    PubMed

    Wang, Ming Li; Morris, J Bradley; Tonnis, Brandon; Pinnow, David; Davis, Jerry; Raymer, Paul; Pederson, Gary A

    2011-09-14

    Castor has tremendous potential as a feedstock for biodiesel production. The oil content and fatty acid composition in castor seed are important factors determining the price for production and affecting the key fuel properties of biodiesel. There are 1033 available castor accessions collected or donated from 48 countries worldwide in the USDA germplasm collection. The entire castor collection was screened for oil content and fatty acid composition by nuclear magnetic resonance (NMR) and gas chromatography (GC), respectively. Castor seeds on the average contain 48.2% oil with significant variability ranging from 37.2 to 60.6%. Methyl esters were prepared from castor seed by alkaline transmethylation. GC analysis of methyl esters confirmed that castor oil was composed primarily of eight fatty acids: 1.48% palmitic (C16:0), 1.58% stearic (C18:0), 4.41% oleic (C18:1), 6.42% linoleic (C18:2), 0.68% linolenic (C18:3), 0.45% gadoleic (C20:1), 84.51% ricinoleic (C18:1-1OH), and 0.47% dihydroxystearic (C18:0-2OH) acids. Significant variability in fatty acid composition was detected among castor accessions. Ricinoleic acid (RA) was positively correlated with dihydroxystearic acid (DHSA) but highly negatively correlated with the five other fatty acids except linolenic acid. The results for oil content and fatty acid composition obtained from this study will be useful for end-users to explore castor germplasm for biodiesel production.

  19. Polylactic acid composites incorporating casein functionalized cellulose nanowhiskers

    PubMed Central

    2013-01-01

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

  20. Amino Acid Composition of Breast Milk from Urban Chinese Mothers

    PubMed Central

    Garcia-Rodenas, Clara L.; Affolter, Michael; Vinyes-Pares, Gerard; De Castro, Carlos A.; Karagounis, Leonidas G.; Zhang, Yumei; Wang, Peiyu; Thakkar, Sagar K.

    2016-01-01

    Human breast milk (BM) amino acid (AA) composition may be impacted by lactation stage or factors related to geographical location. The present cross-sectional study is aimed at assessing the temporal changes of BMAA over lactation stages in a large cohort of urban mothers in China. Four hundred fifty BM samples, collected in three Chinese cities covering eight months of lactation were analyzed for free (FAA) and total (TAA) AA by o-phthalaldehyde/ fluorenylmethylchloroformate (OPA/FMOC) derivatization. Concentrations and changes over lactation were aligned with previous reports. Both the sum and the individual TAA values significantly decreased during the first periods of lactation and then generally leveled off. Leucine and methionine were respectively the most and the least abundant indispensable amino acids across all the lactation stages, whereas glutamic acid + glutamine (Glx) was the most and cystine the least abundant dispensable AA. The contribution of FAA to TAA levels was less than 2%, except for free Glx, which was the most abundant FAA. In conclusion, the AA composition of the milk from our cohort of urban Chinese mothers was comparable to previous studies conducted in other parts of the world, suggesting that this is an evolutionary conserved trait largely independent of geographical, ethnic, or dietary factors. PMID:27690094

  1. Determination of Acidity Constants by Gradient Flow-Injection Titration

    ERIC Educational Resources Information Center

    Conceicao, Antonio C. L.; Minas da Piedade, Manuel E.

    2006-01-01

    A three-hour laboratory experiment, designed for an advanced undergraduate course in instrumental analysis that illustrates the application of the gradient chamber flow-injection titration (GCFIT) method with spectrophotometric detection to determine acidity constants is presented. The procedure involves the use of an acid-base indicator to obtain…

  2. Relationship between cannabinoids content and composition of fatty acids in hempseed oils.

    PubMed

    Petrović, Marinko; Debeljak, Željko; Kezić, Nataša; Džidara, Petra

    2015-03-01

    Hempseed oils acquired on the Croatian markets were characterised by cannabinoid content and fatty acid composition. The new method for determination of cannabinoid content was developed and validated in the range of 0.05-60 mg/kg, and the content of tetrahydrocannabinol varied between 3.23 and 69.5 mg/kg. Large differences among the samples were obtained for phenotype ratio suggesting that not all of analysed hempseed oils were produced from industrial hemp. Sample clustering based on cannabinoid content assigned samples to two groups closely related to the phenotype ratios obtained. The results of this study confirm that hempseed oil is a good source of polyunsaturated fatty acids, especially γ-linolenic and stearidonic acid, but the content varies a lot more than the omega-6/omega-3 ratio. The grouping of samples on fatty acid content assigned samples to two groups which were consistent with the groups obtained based on cannabinoid content clustering. PMID:25306338

  3. Relationship between cannabinoids content and composition of fatty acids in hempseed oils.

    PubMed

    Petrović, Marinko; Debeljak, Željko; Kezić, Nataša; Džidara, Petra

    2015-03-01

    Hempseed oils acquired on the Croatian markets were characterised by cannabinoid content and fatty acid composition. The new method for determination of cannabinoid content was developed and validated in the range of 0.05-60 mg/kg, and the content of tetrahydrocannabinol varied between 3.23 and 69.5 mg/kg. Large differences among the samples were obtained for phenotype ratio suggesting that not all of analysed hempseed oils were produced from industrial hemp. Sample clustering based on cannabinoid content assigned samples to two groups closely related to the phenotype ratios obtained. The results of this study confirm that hempseed oil is a good source of polyunsaturated fatty acids, especially γ-linolenic and stearidonic acid, but the content varies a lot more than the omega-6/omega-3 ratio. The grouping of samples on fatty acid content assigned samples to two groups which were consistent with the groups obtained based on cannabinoid content clustering.

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

    PubMed

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

    2012-07-01

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

  5. Spectrophotometric method for determining gibberellic acid in fermentation broths.

    PubMed

    Berríos, Julio; Illanes, Andrés; Aroca, Germán

    2004-01-01

    A novel method for the quantitative determination of gibberellic acid in fermentation broths has been developed. It is based on the kinetic of the reaction of conversion of gibberellic acid to gibberellenic acid. The method is simple, reliable, faster than most of methods known, and free of the interferences which commonly affect spectrophotometric methods currently in use. Its threshold sensitivity is 0.1 g and its accuracy is greater than 97% for concentrations of gibberellic acid ranging from 0.1 to 1 g l(-1).

  6. Acid gas scrubbing by composite solvent-swollen membranes

    DOEpatents

    Matson, Stephen L.; Lee, Eric K. L.; Friesen, Dwayne T.; Kelly, Donald J.

    1988-01-01

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

  7. Acid gas scrubbing by composite solvent-swollen membranes

    DOEpatents

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

    1988-04-12

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

  8. Iodometric determination of ascorbic acid by controlled potential coulometry.

    PubMed

    Karlsson, R

    1975-12-01

    An iodometric method for the determination of ascorbic acid has been devised. The method is based on previously developed coulometric instrumentation. The stability of different ascorbic acid solutions has been studied and the best conditions have been established. Ascorbic acid has been determined in different kinds of samples but with the main interest on pharmaceutical preparations. Speqial regard has also been paid to the other constituents in such samples, with respect to possible interferences. The error of the coulometric method is about 0.1% and the time of an analysis is in the range 2-6 min.

  9. Conjugated Linoleic Acid Production by Bifidobacteria: Screening, Kinetic, and Composition

    PubMed Central

    Amaretti, Alberto; Leonardi, Alan; Quartieri, Andrea; Gozzoli, Caterina; Rossi, Maddalena

    2016-01-01

    Conjugated linoleic acids (CLA) are positional and geometric isomers of linoleic acid involved in a number of health aspects. In humans, CLA production is performed by gut microbiota, including some species of potential probiotic bifidobacteria. 128 strains of 31 Bifidobacterium species were screened with a spectrophotometric assay to identify novel CLA producers. Most species were nonproducers, while producers belonged to B. breve and B. pseudocatenulatum. GC-MS revealed that CLA producer strains yielded 9cis,11trans-CLA and 9trans,11trans-CLA, without any production of other isomers. Hydroxylated forms of LA were absent in producer strains, suggesting that the myosin-cross-reactive antigen (MCRA) protein that exerts hydratase activity is not involved in LA isomerization. Moreover, both CLA producer and nonproducer species bear a MCRA homologue. The strain B. breve WC 0421 was the best CLA producer, converting LA into 68.8% 9cis,11trans-CLA and 25.1% 9trans,11trans-CLA. Production occurred mostly during the lag and the exponential phase. For the first time, production and incorporation of CLA in biomass were assessed. B. breve WC 0421 stored CLA in the form of free fatty acids, without changing the composition of the esterified fatty acids, which mainly occurred in the plasmatic membrane. PMID:27429985

  10. Determination of liquid-liquid critical point composition using 90∘ laser light scattering

    NASA Astrophysics Data System (ADS)

    Williamson, J. Charles; Brown, Allison M.; Helvie, Elise N.; Dean, Kevin M.

    2016-04-01

    Despite over a century of characterization efforts, liquid-liquid critical point compositions are difficult to identify with good accuracy. Reported values vary up to 10% for even well-studied systems. Here, a technique is presented for high-precision determination of the critical composition of a partially miscible binary liquid system. Ninety-degree laser light-scattering intensities from single-phase samples are analyzed using an equation derived from nonclassical power laws and the pseudospinodal approximation. Results are reported for four liquid-liquid systems (aniline + hexane, isobutyric acid + water, methanol + cyclohexane, and methanol + carbon disulfide). Compared to other methods, the 90∘ light-scattering approach has a strong dependence on composition near the critical point, is less affected by temperature fluctuations, and is insensitive to the presence of trace impurities in the samples. Critical compositions found with 90∘ light scattering are precise to the parts-per-thousand level and show long-term reproducibility.

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

    PubMed

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

    2013-01-01

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

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

    PubMed

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

    2013-01-01

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

  13. Moisture determination in composite materials using positron lifetime techniques

    NASA Technical Reports Server (NTRS)

    Singh, J. J.; Holt, W. R.; Mock, W., Jr.

    1980-01-01

    A technique was developed which has the potential of providing information on the moisture content as well as its depth in the specimen. This technique was based on the dependence of positron lifetime on the moisture content of the composite specimen. The positron lifetime technique of moisture determination and the results of the initial studies are described.

  14. DETERMINATION OF PYRETHROID PESTICIDES IN COMPOSITE DIETARY SAMPLES

    EPA Science Inventory

    The U.S. Environmental Protection Agency's National Exposure Research Laboratory (NERL) conducts aggregate exposure studies for determining an individual's exposure to a broad range of target analytes in composite dietary samples. The objective of this work is to develop an anal...

  15. Computer program determines chemical composition of physical system at equilibrium

    NASA Technical Reports Server (NTRS)

    Kwong, S. S.

    1966-01-01

    FORTRAN 4 digital computer program calculates equilibrium composition of complex, multiphase chemical systems. This is a free energy minimization method with solution of the problem reduced to mathematical operations, without concern for the chemistry involved. Also certain thermodynamic properties are determined as byproducts of the main calculations.

  16. Fatty acids determination in Bronte pistachios by gas chromatographic method.

    PubMed

    Pantano, Licia; Lo Cascio, Giovanni; Alongi, Angelina; Cammilleri, Gaetano; Vella, Antonio; Macaluso, Andrea; Cicero, Nicola; Migliazzo, Aldo; Ferrantelli, Vincenzo

    2016-10-01

    A gas chromatographic with flame ionization detector (GC-MS FID) method for the identification and quantification of fatty acids based on the extraction of lipids and derivatisation of free acids to form methyl esters was developed and validated. The proposed method was evaluated to a number of standard FAs, and Bronte pistachios samples were used for that purpose and to demonstrate the applicability of the proposed method. In this regard, repeatability, mean and standard deviation of the analytical procedure were calculated. The results obtained have demonstrated oleic acid as the main component of Bronte pistachios (72.2%) followed by linoleic acid (13.4%) and showed some differences in composition with respect to Tunisian, Turkish and Iranian pistachios.

  17. Fatty acids determination in Bronte pistachios by gas chromatographic method.

    PubMed

    Pantano, Licia; Lo Cascio, Giovanni; Alongi, Angelina; Cammilleri, Gaetano; Vella, Antonio; Macaluso, Andrea; Cicero, Nicola; Migliazzo, Aldo; Ferrantelli, Vincenzo

    2016-10-01

    A gas chromatographic with flame ionization detector (GC-MS FID) method for the identification and quantification of fatty acids based on the extraction of lipids and derivatisation of free acids to form methyl esters was developed and validated. The proposed method was evaluated to a number of standard FAs, and Bronte pistachios samples were used for that purpose and to demonstrate the applicability of the proposed method. In this regard, repeatability, mean and standard deviation of the analytical procedure were calculated. The results obtained have demonstrated oleic acid as the main component of Bronte pistachios (72.2%) followed by linoleic acid (13.4%) and showed some differences in composition with respect to Tunisian, Turkish and Iranian pistachios. PMID:27265004

  18. Hydrogen Isotopic Composition of Particulate-Bound Fatty Acids From the California Borderland Basins

    NASA Astrophysics Data System (ADS)

    Jones, A. A.; Sessions, A. L.; Campbell, B. J.; Valentine, D. L.

    2006-12-01

    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 δD 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 δD values were measured. Values of δD for specific fatty acids were generally consistent between stations. Saturated fatty acids (C14, C16, and C18) yielded δD values ranging from -230‰ to -132‰, with δD 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 (δD values ranging from -186‰ to -68‰) relative to 20:5 (-208‰ to -93‰). Unsaturated fatty acids tended to have more positive δD 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 δD 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 δD values

  19. [EFFECT OF MYCOPLASMA INFECTION TO FATTY ACID COMPOSITION OF CALLUS CULTURE SUGAR BEET].

    PubMed

    Panchenko, L P; Korobkova, K S; Ostapchuk, A N

    2015-01-01

    It was studied the effect of Acholeplasma laidlawii var. granulum str. 118 to fatty acid composition of sugar beet calluses. It was established that acting of acholeplasma results to changes in the quantitative content of the individual fatty acids and in the qualitative composition of fatty acids in the lipids of calluses. The changing of the fatty acid composition of calluses lipids of sugar beet infected by A. laidlawii vargranulum str. 118 is observed as nonspecific response to biotic stress. PMID:26829840

  20. Colorimetric determination of phosphoric acid leakage for phosphoric acid-doped polybenzimidazole membrane fuel cell applications

    NASA Astrophysics Data System (ADS)

    Jeong, Yeon Hun; Jung, Ju Hae; Choi, Euiji; Han, Seungyoon; Begley, Alina Irene; Yoo, Sung Jong; Jang, Jong Hyun; Kim, Hyoung-Juhn; Nam, Suk Woo; Lee, Kwan-Young; Kim, Jin Young

    2015-12-01

    A simple and precise colorimetric method for analyzing phosphoric acid leakage in phosphoric acid-doped polybenzimidazole membrane fuel cells is described. The developed method is based on the colorimetric determination from a rapid formation of molybdenum blue color by the reduction reaction of molybdate ions in the presence of phosphoric acid in the acidic medium. The color is stable up to a few months and can be used for the sensitive and accurate detection of phosphoric acid electrolyte which is discharged from the fuel cell during operation. Tests with a wide concentration range of phosphate compounds showed that it permits determination of phosphoric acid up to nanogram quantities. The developed detection method assists monitoring the phosphoric acid contents and developing stable operation strategies of fuel cells.

  1. Changes in fatty acid composition of Chlorella vulgaris by hypochlorous acid.

    PubMed

    Park, Ji-Yeon; Choi, Sun-A; Jeong, Min-Ji; Nam, Bora; Oh, You-Kwan; Lee, Jin-Suk

    2014-06-01

    Hypochlorous acid treatment of a microalga, Chlorella vulgaris, was investigated to improve the quality of microalgal lipid and to obtain high biodiesel-conversion yield. Because chlorophyll deactivates the catalyst for biodiesel conversion, its removal in the lipid-extraction step enhances biodiesel productivity. When microalgae contacted the hypochlorous acid, chlorophyll was removed, and resultant changes in fatty acid composition of microalgal lipid were observed. The lipid-extraction yield after activated clay treatment was 32.7 mg lipid/g cell; after NaClO treatment at 0.8% available chlorine concentration, it was 95.2 mg lipid/g cell; and after NaCl electrolysis treatment at the 1 g/L cell concentration, it was 102.4 mg lipid/g cell. While the contents of all of the unsaturated fatty acids except oleic acid, in the microalgal lipid, decreased as the result of NaClO treatment, the contents of all of the unsaturated fatty acids including oleic acid decreased as the result of NaCl electrolysis treatment. PMID:24785789

  2. Preparation and characterization of dry method esterified starch/polylactic acid composite materials.

    PubMed

    Zuo, Yingfeng; Gu, Jiyou; Yang, Long; Qiao, Zhibang; Tan, Haiyan; Zhang, Yanhua

    2014-03-01

    Corn starch and maleic anhydride were synthesized from a maleic anhydride esterified starch by dry method. Fourier transform infrared spectroscopy (FTIR) was used for the qualitative analysis of the esterified starches. The reaction efficiency of dry method esterified starch reached 92.34%. The dry method esterified starch was blended with polylactic acid (PLA), and the mixture was melted and extruded to produce the esterified starch/polylactic acid (ES/PLA) composites. The degree of crystallinity of the ES/PLA was lower than that of the NS/PLA, indicating that the relative dependence between these two components of starch and polylactic acid was enhanced. Scanning electron microscopy (SEM) indicated that the dry method esterified starch increased the two-phase interface compatibility of the composites, thereby improving the tensile strength, bending strength, and elongation at break of the ES/PLA composite. The introduction of a hydrophobic ester bond and increase in interface compatibility led to an increase in ES/PLA water resistance. Melt index determination results showed that starch esterification modification had improved the melt flow properties of starch/PLA composite material. Strain scanning also showed that the compatibility of ES/PLA was increased. While frequency scanning showed that the storage modulus and complex viscosity of ES/PLA was less than that of NS/PLA.

  3. Preparation and characterization of dry method esterified starch/polylactic acid composite materials.

    PubMed

    Zuo, Yingfeng; Gu, Jiyou; Yang, Long; Qiao, Zhibang; Tan, Haiyan; Zhang, Yanhua

    2014-03-01

    Corn starch and maleic anhydride were synthesized from a maleic anhydride esterified starch by dry method. Fourier transform infrared spectroscopy (FTIR) was used for the qualitative analysis of the esterified starches. The reaction efficiency of dry method esterified starch reached 92.34%. The dry method esterified starch was blended with polylactic acid (PLA), and the mixture was melted and extruded to produce the esterified starch/polylactic acid (ES/PLA) composites. The degree of crystallinity of the ES/PLA was lower than that of the NS/PLA, indicating that the relative dependence between these two components of starch and polylactic acid was enhanced. Scanning electron microscopy (SEM) indicated that the dry method esterified starch increased the two-phase interface compatibility of the composites, thereby improving the tensile strength, bending strength, and elongation at break of the ES/PLA composite. The introduction of a hydrophobic ester bond and increase in interface compatibility led to an increase in ES/PLA water resistance. Melt index determination results showed that starch esterification modification had improved the melt flow properties of starch/PLA composite material. Strain scanning also showed that the compatibility of ES/PLA was increased. While frequency scanning showed that the storage modulus and complex viscosity of ES/PLA was less than that of NS/PLA. PMID:24315947

  4. Fatty acid composition of wild mushroom species of order Agaricales--examination by gas chromatography-mass spectrometry and chemometrics.

    PubMed

    Marekov, Ilko; Momchilova, Svetlana; Grung, Bjørn; Nikolova-Damyanova, Boryana

    2012-12-01

    Applying gas chromatography-mass spectrometry of 4,4-dimethyloxazoline fatty acid derivatives, the fatty acid composition of 15 mushroom species belonging to 9 genera and 5 families of order Agaricales growing in Bulgaria is determined. The structure of 31 fatty acids (not all present in each species) is unambiguously elucidated, with linoleic, oleic and palmitic acids being the main components (ranging between 70.9% (Marasmius oreades) and 91.2% (Endoptychum agaricoides)). A group of three hexadecenoic positionally isomeric fatty acids, 6-, 9- and 11-16:1, appeared to be characteristic components of the examined species. By applying chemometrics it was possible to show that the fatty acid composition closely reflects the classification of the species.

  5. Phenolic Acid Composition and Anti-Parasitic Effects of Four Peucedanum Species on Entamoeba histolytica Trophozoites

    PubMed Central

    DEGERLI, Serpil; TEPE, Bektas

    2015-01-01

    Background: The aim of this study was to determine phenolic acid composition and anti-parasitic effects of Peucedanum caucasicum, P. palimbioides, P. longibracteolatum and P. chryseum on Entamoeba histolytica. Methods: Methanol extracts of the plant species were prepared by soxhlet extraction. Phenolic acid compositions were determined by HPLC. Anti-proliferative effect of extracts on trophozoites was determined by using trypan blue dye exclusion test. For counting the cells, approximately a hundred of E. histolytica trophozoites were examined in each time. The data were presented as mean values with standard deviations and analyzed by repeated measures of ANOVA followed by Tukey test for post-hoc pairwise comparisons. The P-value was set at 0.05 for significance level. Results: All of the extracts showed a time and dose dependent amoebicidal action on trophozoites. Among the extracts tested, P. longibracteolatum showed the strongest amoebicidal effect on the trophozoites. As expected, this plant species also exhibited time and dose dependent activity on the trophozoites. At 4.0 mg/ml extract concentration, all of the trophozoites were killed by the extract in 72nd hour. Gallic (11.144 mg/g), P-hydroxybenzoic (17.646 mg/g), and o-coumaric acids (14.442 mg/g) were determined as the major phenolic acids of P. longibracteolatum. Gallic and P-hydroxybenzoic acids found in P. longibracteolatum could not be determined in other extracts. Therefore, high activity potential of this plant could probably be attributed to the presence of these phytochemicals. Conclusion: P. longibracteolatum can be further evaluated as potential therapeutic drugs for the treatment of Entamoeba infections. PMID:26622297

  6. Determination of the Fatty Acid content of pumpkin seed, pygeum, and saw palmetto.

    PubMed

    Ganzera, M; Croom, E M; Khan, I A

    1999-01-01

    Fatty acids are major components of many plants, foods and medicines, including pumpkin seeds (Cucubita pepo), pygeum bark (Prunus africana) and saw palmetto (Serenoa repens). With the gas chromatography methods reported here, free fatty acids of these species can be quantified as their trimethylsilyl derivatives. Because of their different fatty acid contents and composition, the gas chromatography method can distinguish which of three plant species was extracted, and, in the case of S. repens, the method of extraction. Although phytosterols can be separated by this method, their content is too low to be assigned directly. The total fatty acid content can be determined through formation of the methyl esters. This is helpful for estimation of the kind and percentage of fatty acids that are present as triglyceride esters in the plant material and for standardization of the products.

  7. Adsorption of Acid Red 57 from aqueous solutions onto polyacrylonitrile/activated carbon composite.

    PubMed

    El-Bindary, Ashraf A; Diab, Mostafa A; Hussien, Mostafa A; El-Sonbati, Adel Z; Eessa, Ahmed M

    2014-04-24

    The adsorption of Acid Red 57 (AR57) onto Polyacrylonitrile/activated carbon (PAN/AC) composite was investigated in aqueous solution in a batch system with respect to contact time, pH and temperature. Physical characteristics of (PAN/AC) composite such as fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM) were obtained. Langmuir and Freundlich adsorption models were applied to describe the equilibrium isotherms and the isotherm constants were determined. The activation energy of adsorption was also evaluated for the adsorption of AR57 onto (PAN/AC) composite. The pseudo-first-order and pseudo-second-order kinetic models were used to describe the kinetic data. The dynamic data fitted the pseudo-second-order kinetic model well. The activation energy, change of free energy, enthalpy and entropy of adsorption were also evaluated for the adsorption of AR57 onto (PAN/AC) composite. The thermodynamics of the adsorption indicated spontaneous and exothermic nature of the process. The results indicate that (PAN/AC) composite could be employed as low-cost material for the removal of acid dyes from textile effluents. PMID:24463242

  8. Applicability of ultrasonic testing for the determination of volume fraction of particulates in alumina-reinforced aluminum matrix composites

    SciTech Connect

    Fang, C.K.; Fang, R.L.; Weng, W.P.; Chuang, T.H.

    1999-10-01

    An ultrasonic testing technique was employed to determine the volume fraction of alumina particulate reinforcement in 6061 aluminum matrix composites. this study was performed on various composites with Al{sub 2}O{sub 3} nominal volume fractions of 10, 15, and 20%. For comparison, other techniques were employed as well, including the Archimedes method, metallographic image analysis, X-ray diffraction, and acid dissolution. Observations indicated that ultrasonic testing and acid dissolution methods are more reliable than the other techniques, while ultrasonic testing is faster than the acid dissolution method.

  9. [Spectrophotometric determination of aromatic amino compounds with J-acid].

    PubMed

    Yin, Xiao-hang; Shi, Wen-jian; Shen, Xin; Ma, Jun-tao; Li, Liang

    2015-01-01

    The problems such as chromogenic reaction selectivity, reaction rate, sensitivity and water-solubility of azo compounds were considered. The molecular structures of coupling components were theoretically designed and screened in the present research The reaction conditions and methods of chromogenic reaction were investigated. J-Acid (2-amino-5-naphthol-7-sulfonic acid) as a coupling reagent to determine aromatic amino compounds was established. In the presence of potassium bromide, at room temperature, nitrite reacted with aromatic amino compounds in the medium of thin hydrochloric acid. Then diazonium salt reacted with J-Acid in the aqueous solution of sodium carbonate, forming coloured azo dye, which had a maximum adsorption at 480 nm. The molar adsorption coeffcients of aniline, 4-aminobenzene sulfonic acid and 1-naphthylamine were 3. 95 X 10(4), 3. 24 X 10(4) and 3. 91 X 10(4) L . mol-1 . cm-1 , respectively. Experimental results showed that common coexisting ions on the surface water did not affect the results of determination. J-Acid of spectrophotometry was used to determine the samples of Shanghai Fu Xing Dao canal. Meanwhile, recovery experiments by standard addition method were done. Experiment results showed that the recoveries of aniline were in the range of 98. 5%-102. 1%, and RSD was 2. 08%. J-Acid is a common organic reagent. It is soluble in water and low volatile, and its toxicity is much lower than N-ethylenediamine. spectrophotometric determination of aromatic amino compounds by J-Acid has the advantage of high sensitivity, good selectivity, simple rapid operation and accurate results, and thus it can be used for the determination of trace aromatic amino compounds in the environmental water.

  10. GC constituents and relative codon expressed amino acid composition in cyanobacterial phycobiliproteins.

    PubMed

    Kannaujiya, Vinod K; Rastogi, Rajesh P; Sinha, Rajeshwar P

    2014-08-10

    The genomic as well as structural relationship of phycobiliproteins (PBPs) in different cyanobacterial species are determined by nucleotides as well as amino acid composition. The genomic GC constituents influence the amino acid variability and codon usage of particular subunit of PBPs. We have analyzed 11 cyanobacterial species to explore the variation of amino acids and causal relationship between GC constituents and codon usage. The study at the first, second and third levels of GC content showed relatively more amino acid variability on the levels of G3+C3 position in comparison to the first and second positions. The amino acid encoded GC rich level including G rich and C rich or both correlate the codon variability and amino acid availability. The fluctuation in amino acids such as Arg, Ala, His, Asp, Gly, Leu and Glu in α and β subunits was observed at G1C1 position; however, fluctuation in other amino acids such as Ser, Thr, Cys and Trp was observed at G2C2 position. The coding selection pressure of amino acids such as Ala, Thr, Tyr, Asp, Gly, Ile, Leu, Asn, and Ser in α and β subunits of PBPs was more elaborated at G3C3 position. In this study, we observed that each subunit of PBPs is codon specific for particular amino acid. These results suggest that genomic constraint linked with GC constituents selects the codon for particular amino acids and furthermore, the codon level study may be a novel approach to explore many problems associated with genomics and proteomics of cyanobacteria.

  11. Determination of linoleic acid in toothpaste by gas chromatography with flame ionization detection.

    PubMed

    Wejnerowska, Grazyna; Gackowska, Alicja; Gaca, Jerzy

    2008-06-01

    A new method for the determination of linoleic acid (LA) in toothpaste by a routine analysis has been proposed. Studies were based on the ISO 5509 procedure, which was modified for the purpose of LA determination in the toothpaste. Gas chromatography (GC) was employed for the qualitative and quantitative determination of linoleic acid methyl ester. The content of LA (5.31%) in sunflower oil added to the toothpaste composition (0.5%) was determined, and then the optimization studies for the determination of LA in the toothpaste samples were carried out. The relative standard deviation (RSD) of the procedure developed was 9.96% (n = 9). The quantitative analysis showed that the content of LA in the toothpaste samples studied was 0.0258 +/- 0.0011%. The detection limit of LA in toothpaste was approximately 0.001%.

  12. The determination of ice composition with instruments on cometary landers.

    PubMed

    Boynton, W V; D'Uston, L C; Young, D T; Lunine, J I; Waite, J H; Bailey, S H; Berthelier, J J; Bertaux, J L; Borrel, V; Burke, M F; Cohen, B A; McComas, D H; Nordholt, J E; Evans, L G; Trombka, J I

    1997-05-01

    The determination of the composition of materials that make up comets is essential in trying to understand the origin of these primitive objects. The ices especially could be made in several different astrophysical settings including the solar nebula, protosatellite nebulae of the giant planets, and giant molecular clouds that predate the formation of the solar system. Each of these environments makes different ices with different composition. In order to understand the origin of comets, one needs to determine the composition of each of the ice phases. For example, it is of interest to know that comets contain carbon monoxide, CO, but it is much more important to know how much of it is a pure solid phase, is trapped in clathrate hydrates, or is adsorbed on amorphous water ice. In addition, knowledge of the isotopic composition of the constituents will help determine the process that formed the compounds. Finally, it is important to understand the bulk elemental composition of the nucleus. When these data are compared with solar abundances, they put strong constraints on the macro-scale processes that formed the comet. A differential scanning calorimeter (DSC) and an evolved gas analyzer (EGA) will make the necessary association between molecular constituents and their host phases. This combination of instruments takes a small (tens of mg) sample of the comet and slowly heats it in a sealed oven. As the temperature is raised, the DSC precisely measures the heat required, and delivers the gases to the EGA. Changes in the heat required to raise the temperature at a controlled rate are used to identify phase transitions, e.g., crystallization of amorphous ice or melting of hexagonal ice, and the EGA correlates the gases released with the phase transition. The EGA consists of two mass spectrometers run in tandem. The first mass spectrometer is a magnetic-sector ion-momentum analyzer (MAG), and the second is an electrostatic time-of-flight analyzer (TOF). The TOF acts as

  13. The determination of ice composition with instruments on cometary landers.

    PubMed

    Boynton, W V; D'Uston, L C; Young, D T; Lunine, J I; Waite, J H; Bailey, S H; Berthelier, J J; Bertaux, J L; Borrel, V; Burke, M F; Cohen, B A; McComas, D H; Nordholt, J E; Evans, L G; Trombka, J I

    1997-05-01

    The determination of the composition of materials that make up comets is essential in trying to understand the origin of these primitive objects. The ices especially could be made in several different astrophysical settings including the solar nebula, protosatellite nebulae of the giant planets, and giant molecular clouds that predate the formation of the solar system. Each of these environments makes different ices with different composition. In order to understand the origin of comets, one needs to determine the composition of each of the ice phases. For example, it is of interest to know that comets contain carbon monoxide, CO, but it is much more important to know how much of it is a pure solid phase, is trapped in clathrate hydrates, or is adsorbed on amorphous water ice. In addition, knowledge of the isotopic composition of the constituents will help determine the process that formed the compounds. Finally, it is important to understand the bulk elemental composition of the nucleus. When these data are compared with solar abundances, they put strong constraints on the macro-scale processes that formed the comet. A differential scanning calorimeter (DSC) and an evolved gas analyzer (EGA) will make the necessary association between molecular constituents and their host phases. This combination of instruments takes a small (tens of mg) sample of the comet and slowly heats it in a sealed oven. As the temperature is raised, the DSC precisely measures the heat required, and delivers the gases to the EGA. Changes in the heat required to raise the temperature at a controlled rate are used to identify phase transitions, e.g., crystallization of amorphous ice or melting of hexagonal ice, and the EGA correlates the gases released with the phase transition. The EGA consists of two mass spectrometers run in tandem. The first mass spectrometer is a magnetic-sector ion-momentum analyzer (MAG), and the second is an electrostatic time-of-flight analyzer (TOF). The TOF acts as

  14. Cuticle Fatty Acid Composition and Differential Susceptibility of Three Species of Cockroaches to the Entomopathogenic Fungi Metarhizium anisopliae (Ascomycota, Hypocreales).

    PubMed

    Gutierrez, Alejandra C; Gołębiowski, Marek; Pennisi, Mariana; Peterson, Graciela; García, Juan J; Manfrino, Romina G; López Lastra, Claudia C

    2015-04-01

    Differences in free fatty acids (FFAs) chemical composition of insects may be responsible for susceptibility or resistance to fungal infection. Determination of FFAs found in cuticular lipids can effectively contribute to the knowledge concerning insect defense mechanisms. In this study, we have evaluated the susceptibility of three species of cockroaches to the entomopathogenic fungi Metarhizium anisopliae (Metschnikoff) Sorokin by topical application. Mortality due to M. anisopliae was highly significant on adults and nymphs of Blattella germanica L. (Blattodea: Blattellidae). However, mortality was faster in adults than in nymphs. Adults of Blatta orientalis L. (Blattodea: Blattidae) were not susceptible to the fungus, and nymphs of Blaptica dubia Serville (Blattodea: Blaberidae) were more susceptible to the fungus than adults. The composition of cuticular FFAs in the three species of cockroaches was also studied. The analysis indicated that all of the fatty acids were mostly straight-chain, long-chain, saturated or unsaturated. Cuticular lipids of three species of cockroaches contained 19 FFAs, ranging from C14:0 to C24:0. The predominant fatty acids found in the three studied species of cockroaches were oleic, linoleic, palmitic, and stearic acid. Only in adults of Bl. orientalis, myristoleic acid, γ-linolenic acid, arachidic acid, dihomolinoleic acid, and behenic acid were identified. Lignoceric acid was detected only in nymphs of Bl. orientalis. Heneicosylic acid and docosahexaenoic acid were identified in adults of Ba. dubia. PMID:26470187

  15. Cuticle Fatty Acid Composition and Differential Susceptibility of Three Species of Cockroaches to the Entomopathogenic Fungi Metarhizium anisopliae (Ascomycota, Hypocreales).

    PubMed

    Gutierrez, Alejandra C; Gołębiowski, Marek; Pennisi, Mariana; Peterson, Graciela; García, Juan J; Manfrino, Romina G; López Lastra, Claudia C

    2015-04-01

    Differences in free fatty acids (FFAs) chemical composition of insects may be responsible for susceptibility or resistance to fungal infection. Determination of FFAs found in cuticular lipids can effectively contribute to the knowledge concerning insect defense mechanisms. In this study, we have evaluated the susceptibility of three species of cockroaches to the entomopathogenic fungi Metarhizium anisopliae (Metschnikoff) Sorokin by topical application. Mortality due to M. anisopliae was highly significant on adults and nymphs of Blattella germanica L. (Blattodea: Blattellidae). However, mortality was faster in adults than in nymphs. Adults of Blatta orientalis L. (Blattodea: Blattidae) were not susceptible to the fungus, and nymphs of Blaptica dubia Serville (Blattodea: Blaberidae) were more susceptible to the fungus than adults. The composition of cuticular FFAs in the three species of cockroaches was also studied. The analysis indicated that all of the fatty acids were mostly straight-chain, long-chain, saturated or unsaturated. Cuticular lipids of three species of cockroaches contained 19 FFAs, ranging from C14:0 to C24:0. The predominant fatty acids found in the three studied species of cockroaches were oleic, linoleic, palmitic, and stearic acid. Only in adults of Bl. orientalis, myristoleic acid, γ-linolenic acid, arachidic acid, dihomolinoleic acid, and behenic acid were identified. Lignoceric acid was detected only in nymphs of Bl. orientalis. Heneicosylic acid and docosahexaenoic acid were identified in adults of Ba. dubia.

  16. Fatty acid composition of seeds of some species of Nepeta L.

    PubMed

    Kiliç, Turgut; Dirmenci, Tuncay; Gören, Ahmet C

    2007-05-01

    The fatty acid compositions of Nepeta viscida, N. cilicica, N. crinita, N. nuda ssp. glandulifera and N. aristata were analyzed by GC/MS. The main free fatty acids were found as linolenic acid (49.8-58.5%), linoleic acid (10.9-23.5%), oleic acid (11.5-19.2%), palmitic acid (5.2-6.8%) and stearic acid (2.0-3.7%) and, total fatty acid compositions of species were analyzed and results were found as 36.2-49.8%, 17.1-25.8%, 15.4-25.8%, 6.4-7.8%, and 2.7-4.1%, respectively.

  17. Determination of the Efficiency of Mixed-Acid Digestions of Sediments

    SciTech Connect

    Huerta Vazquez, Alejandra I.; Gill, Gary A.

    2007-01-01

    Mixed-acid digestion is a method often used for the determination of elemental analysis of sediment samples. It is crucial that efficiency details associated with the digestion method be well understood on an element by element basis. Battelle’s Marine Sciences Laboratory Standard Operating Procedure for Sediment Mixed-Acid Digestions was modified to identify conditions which produce optimal recovery of elements. The parameters that were adjusted for testing were mass of sediment, mixed-acid volume, mixed-acid composition and digestion time. Digestion involves treatment of the sediment sample with mixed-acid mixtures at 135º C ± 10º in a Teflon® digestion bomb. Typical analytical methods include Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) and Inductively Coupled Plasma – Mass Spectrometry (ICP-MS). Initial experiments involved determining the optimal ratio of acid volume to mass of sediment. Experiments were designed to identify the point at which insufficient acid was used to effectively digest a given mass of sediment. When the mass of sediment was varied between 0.2 and 1.0 gram using a 4 mL aqua regia acid mixture (3 mL hydrochloric acid and 1 mL nitric acid), there was no effect on the recovery of the elements Al, Ba, Ca, Co, Cr, Cu, Fe, Mg, Mn, Ni, Pb, Sr, Ti, V, and Zn. The next experiments focused on a time study to resolve the shortest digestive time for optimal elemental recovery. Two masses of sediment were investigated, 0.25 and 0.7 g, again utilizing aqua regia digestion (4 mL). Maximum recovery was reached after 4 hours of digestion; additional digestion time released no or only minimal amounts of elements from the sediments. The final set of experiments was designed to identify optimal conditions for the total digestion of sediment using a mixture of hydrochloric acid, nitric acid, hydrofluoric acid, hydrogen peroxide, and boric acid. These experiments were designed to determine the optimal volume of hydrofluoric acid

  18. Effects of feeding bile acids and a bile acid sequestrant on hepatic bile acid composition in mice.

    PubMed

    Zhang, Youcai; Klaassen, Curtis D

    2010-11-01

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

  19. Effect of fermentation and subsequent pasteurization processes on amino acids composition of orange juice.

    PubMed

    Cerrillo, I; Fernández-Pachón, M S; Collado-González, J; Escudero-López, B; Berná, G; Herrero-Martín, G; Martín, F; Ferreres, F; Gil-Izquierdo, A

    2015-06-01

    The fermentation of fruit produces significant changes in their nutritional composition. An orange beverage has been obtained from the controlled alcoholic fermentation and thermal pasteurization of orange juice. A study was performed to determine the influence of both processes on its amino acid profile. UHPLC-QqQ-MS/MS was used for the first time for analysis of orange juice samples. Out of 29 amino acids and derivatives identified, eight (ethanolamine, ornithine, phosphoethanolamine, α-amino-n-butyric acid, hydroxyproline, methylhistidine, citrulline, and cystathionine) have not previously been detected in orange juice. The amino acid profile of the orange juice was not modified by its processing, but total amino acid content of the juice (8194 mg/L) was significantly increased at 9 days of fermentation (13,324 mg/L). Although the pasteurization process produced partial amino acid degradation, the total amino acid content was higher in the final product (9265 mg/L) than in the original juice, enhancing its nutritional value.

  20. Effect of growth phase on the fatty acid compositions of four species of marine diatoms

    NASA Astrophysics Data System (ADS)

    Liang, Ying; Mai, Kangsen

    2005-04-01

    The fatty acid compositions of four species of marine diatoms ( Chaetoceros gracilis MACC/B13, Cylindrotheca fusiformis MACC/B211, Phaeodactylum tricornutum MACC/B221 and Nitzschia closterium MACC/B222), cultivated at 22°C±1°C with the salinity of 28 in f/2 medium and harvested in the exponential growth phase, the early stationary phase and the late stationary phase, were determined. The results showed that growth phase has significant effect on most fatty acid contents in the four species of marine diatoms. The proportions of 16:0 and 16:1n-7 fatty acids increased while those of 16:3n-4 and eicosapentaenoic acid (EPA) decreased with increasing culture age in all species studied. The subtotal of saturated fatty acids (SFA) increased with the increasing culture age in all species with the exception of B13. The subtotal of monounsaturated fatty acids (MUFA) increased while that of polyunsaturated fatty acids (PUFA) decreased with culture age in the four species of marine diatoms. MUFA reached their lowest value in the exponential growth phase, whereas PUFA reached their highest value in the same phase.

  1. Liquid chromatographic determination of carminic acid in yogurt.

    PubMed

    Jalón, M; Peña, M J; Rivas, J C

    1989-01-01

    A reverse-phase liquid chromatographic method is described for the determination of carminic acid in yogurt. A C18 column is used with acetonitrile-1.19M formic acid (19 + 81) as mobile phase and diode array detection. Sample preparation includes deproteinization with papain and purification in a polyamide column. The relative standard deviation for repeated determinations of carminic acid in a commercial strawberry-flavored yogurt was 3.0%. Recoveries of carminic acid added to a natural-flavored yogurt ranged from 87.2 to 95.3% with a mean of 90.2%. The method permits measurement of amounts as low as 0.10 mg/kg. PMID:2708269

  2. Kinetic-spectrophotometric determination of ascorbic acid by inhibition of the hydrochloric acid-bromate reaction

    NASA Astrophysics Data System (ADS)

    Ensafi, Ali A.; Rezaei, B.; Movahedinia, H.

    2002-10-01

    A new analytical method was developed for the determination of ascorbic acid in fruit juice and pharmaceuticals. The method is based on its inhibition effect on the reaction between hydrochloric acid and bromate. The decolourisation of Methyl Orange by the reaction products was used to monitor the reaction spectrophotometrically at 510 nm. The linearity range of the calibration graph depends on bromate concentration. The variable affecting the rate of the reaction was investigated. The method is simple, rapid, relatively sensitive and precise. The limit of detection is 7.6×10 -6 M and calibration rang is 8×10 -6-1.2×10 -3 M ascorbic acid. The relative standard deviation of seven replication determinations of 8×10 -6 and 2×10 -5 M ascorbic acid was 2.8 and 1.7%, respectively. The influence of potential interfering substance was studied. The method was successfully applied for the determination of ascorbic acid in pharmaceuticals.

  3. A Systems Genetics Approach Identifies Gene Regulatory Networks Associated with Fatty Acid Composition in Brassica rapa Seed.

    PubMed

    Basnet, Ram Kumar; Del Carpio, Dunia Pino; Xiao, Dong; Bucher, Johan; Jin, Mina; Boyle, Kerry; Fobert, Pierre; Visser, Richard G F; Maliepaard, Chris; Bonnema, Guusje

    2016-01-01

    Fatty acids in seeds affect seed germination and seedling vigor, and fatty acid composition determines the quality of seed oil. In this study, quantitative trait locus (QTL) mapping of fatty acid and transcript abundance was integrated with gene network analysis to unravel the genetic regulation of seed fatty acid composition in a Brassica rapa doubled haploid population from a cross between a yellow sarson oil type and a black-seeded pak choi. The distribution of major QTLs for fatty acids showed a relationship with the fatty acid types: linkage group A03 for monounsaturated fatty acids, A04 for saturated fatty acids, and A05 for polyunsaturated fatty acids. Using a genetical genomics approach, expression quantitative trait locus (eQTL) hotspots were found at major fatty acid QTLs on linkage groups A03, A04, A05, and A09. An eQTL-guided gene coexpression network of lipid metabolism-related genes showed major hubs at the genes BrPLA2-ALPHA, BrWD-40, a number of seed storage protein genes, and the transcription factor BrMD-2, suggesting essential roles for these genes in lipid metabolism. Three subnetworks were extracted for the economically important and most abundant fatty acids erucic, oleic, linoleic, and linolenic acids. Network analysis, combined with comparison of the genome positions of cis- or trans-eQTLs with fatty acid QTLs, allowed the identification of candidate genes for genetic regulation of these fatty acids. The generated insights in the genetic architecture of fatty acid composition and the underlying complex gene regulatory networks in B. rapa seeds are discussed.

  4. A Systems Genetics Approach Identifies Gene Regulatory Networks Associated with Fatty Acid Composition in Brassica rapa Seed.

    PubMed

    Basnet, Ram Kumar; Del Carpio, Dunia Pino; Xiao, Dong; Bucher, Johan; Jin, Mina; Boyle, Kerry; Fobert, Pierre; Visser, Richard G F; Maliepaard, Chris; Bonnema, Guusje

    2016-01-01

    Fatty acids in seeds affect seed germination and seedling vigor, and fatty acid composition determines the quality of seed oil. In this study, quantitative trait locus (QTL) mapping of fatty acid and transcript abundance was integrated with gene network analysis to unravel the genetic regulation of seed fatty acid composition in a Brassica rapa doubled haploid population from a cross between a yellow sarson oil type and a black-seeded pak choi. The distribution of major QTLs for fatty acids showed a relationship with the fatty acid types: linkage group A03 for monounsaturated fatty acids, A04 for saturated fatty acids, and A05 for polyunsaturated fatty acids. Using a genetical genomics approach, expression quantitative trait locus (eQTL) hotspots were found at major fatty acid QTLs on linkage groups A03, A04, A05, and A09. An eQTL-guided gene coexpression network of lipid metabolism-related genes showed major hubs at the genes BrPLA2-ALPHA, BrWD-40, a number of seed storage protein genes, and the transcription factor BrMD-2, suggesting essential roles for these genes in lipid metabolism. Three subnetworks were extracted for the economically important and most abundant fatty acids erucic, oleic, linoleic, and linolenic acids. Network analysis, combined with comparison of the genome positions of cis- or trans-eQTLs with fatty acid QTLs, allowed the identification of candidate genes for genetic regulation of these fatty acids. The generated insights in the genetic architecture of fatty acid composition and the underlying complex gene regulatory networks in B. rapa seeds are discussed. PMID:26518343

  5. Fluorimetric determination of pipemidinic acid using the europium chelate.

    PubMed

    Egorova, A; Beltyukova, S; Teslyuk, O

    1999-11-01

    The sensitized luminescence of europium ion in the complexes with pipemidinic acid is investigated. It was shown that in the result of intramolecular energy transfer from ligand to lanthanide ion the luminescence intensity of the latter increases by 10(10) times. The luminescence properties of the complex were studied and the high sensitive luminescence method for the determination of pipemidinic acid has been developed.

  6. Lipid and fatty acid compositions of cod ( Gadus morhua), haddock ( Melanogrammus aeglefinus) and halibut ( Hippoglossus hippoglossus)

    NASA Astrophysics Data System (ADS)

    Zeng, Duan; Mai, Kangsen; Ai, Qinghui; Milley, Joyce E.; Lall, Santosh P.

    2010-12-01

    This study was conducted to compare lipid and fatty acid composition of cod, haddock and halibut. Three groups of cod (276 g ± 61 g), haddock (538 g ± 83 g) and halibut (3704 g ± 221 g) were maintained with commercial feeds mainly based on fish meal and marine fish oil for 12 weeks prior to sampling. The fatty acid compositions of muscle and liver were determined by GC/FID after derivatization of extracted lipids into fatty acid methyl esters (FAME). Lipids were also fractionated into neutral and polar lipids using Waters silica Sep-Pak?. The phospholipid fraction was further separated by high-performance thin-layer chromatography (HPTLC) and the FAME profile was obtained. Results of the present study showed that cod and haddock were lean fish and their total muscle lipid contents were 0.8% and 0.7%, respectively, with phospholipid constituting 83.6% and 87.5% of the total muscle lipid, respectively. Halibut was a medium-fat fish and its muscle lipid content was 8%, with 84% of the total muscle lipid being neutral lipid. Total liver lipid contents of cod, haddock and halibut were 36.9%, 67.2% and 30.7%, respectively, of which the neutral lipids accounted for the major fraction (88.1%-97.1%). Polyunsaturated fatty acids were the most abundant in cod and haddock muscle neutral lipid. Monounsaturated fatty acid level was the highest in halibut muscle neutral lipid. Fatty acid compositions of phospholipid were relatively constant. In summary, the liver of cod and haddock as lean fish was the main lipid reserve organ, and structural phospholipid is the major lipid form in flesh. However, as a medium-fat fish, halibut stored lipid in both their liver and muscle.

  7. Determination of dicarboxylic acids in tropospherical particles and cloudwater

    NASA Astrophysics Data System (ADS)

    v. Pinxteren, D.; Brüggemann, E.; Herrmann, H.

    2003-04-01

    During two FEBUKO (field investigations of budgets and conversions of particle phase organics in troposheric cloud processes) field campaigns aerosol particle and cloudwater samples were taken in a forestal region in Germany (Thüringer Wald). Particle collection took place in fall 2001 and 2002 at two valley sites (luff and lee) of the mountain Schmücke. On top of this mountain cloudwater was sampled. The aim was to collect and physically and chemically characterize air masses before, while and after passing an orographic cloud in order to provide information about possible multiphase interactions and chemical processing of the aerosol. In this campaign capillary electrophoresis (CE) has been used to determine the dicarboxylic acids. CE has some important advantages for the analysis of ions in aerosol particles compared to the commonly used ion chromatography or gas chromatography. The absolute detection limits are very low (below 1 pmole) and it has a large range of signal-to-concentration linearity. Thus it suits to difficult matrices with strongly changing concentrations and compositions such as aerosol samples. The separation efficiency is usually much higher than in liquid chromatography and the required sample amount is low (down to <1 µL). For sampling of the particles a five-stage low-pressure cascade impactor was used. A humidity-controlled tube bundle served as the inlet device. Tedlar foil was used as an impaction substrate then used for ion analysis. For cloudwater sampling four cloudwater collectors from the California Institute of Technology (CASCC2) were used, which collect droplets with a 50% cut off diameter of 3,5 µm by inertial impaction on several rows of teflon strands. Upcoming results of the measurements are presented.

  8. Stimulation of proliferation of an essential fatty acid-deficient fish cell line by C20 and C22 polyunsaturated fatty acids and effects on fatty acid composition.

    PubMed

    Tocher, D R; Dick, J R; Sargent, J R

    1996-11-01

    Recently we reported the development of a fish cell line, EPC-EFAD, derived from the carp (Cyprinus carpio) epithelial papilloma line, EPC, that could survive and proliferate in essential fatty acid-deficient (EFAD) medium. The EPC-EFAD cell line may be a useful model system in which to study the cellular biochemical effects of EFA deficiency and has advantages in studies of polyunsaturated fatty acid (PUFA) and eicosanoid metabolism in fish in that the complications introduced by culture in relatively n-6 PUFA-rich mammalian sera are removed. In the present study, the effects on cell proliferation rate of supplementing EPC-EFAD cells with various n-3 and n-6 PUFA were investigated to determine the possible role(s) of PUFA in cell growth and division. The selectivity of incorporation of specific PUFA into individual glycerophospholipid classes and the feasibility of reproducing in vivo fatty acid compositions in vitro were also investigated. Proliferation of the EPC-EFAD cell line was stimulated by arachidonic (20:4 n-6), eicosapentaenoic (20:5 n-3) and docosahexaenoic (22:6 n-3) fatty acids but not by 18:2 n-6 or 18:3 n-3. The differential effects of PUFA on cellular proliferation may be related to the lack of significant delta 5 desaturase activity in the cells at 22 degrees C and may implicate a role for eicosanoids in the mechanism of stimulation of proliferation. PUFA supplementation increased the cytotoxic effects of longer term culture, an effect that was partly alleviated by inclusion of vitamin E in the culture medium. The cells could generally be supplemented with PUFA to produce cellular fatty acid compositions in vitro that were similar to in vivo compositions. PMID:8981632

  9. Determination of Residual Stress in Composite Materials Using Ultrasonic Waves

    NASA Technical Reports Server (NTRS)

    Rokhlin, S. I.

    1997-01-01

    The performance of high temperature composites can be significantly affected by the presence of residual stresses. These stresses arise during cooling processes from fabrication to room temperature due to mismatch of thermal expansion coefficients between matrix and fiber materials. This effect is especially pronounced in metal matrix and intermetallic composites. It can lead to plastic deformations, matrix cracking and fiber/matrix interface debonding. In this work the feasibility of ultrasonic techniques for residual stress assessment in composites is addressed. A novel technique for absolute stress determination in orthotropic materials from angular dependencies of ultrasonic velocities is described. The technique is applicable for determination of both applied and residual stresses and does not require calibration measurements on a reference sample. The important advantage of this method is that stress is determined simultaneously with stress-dependent elastic constants and is thus decoupled from the material texture. It is demonstrated that when the principal plane stress directions coincide with acoustical axes, the angular velocity data in the plane perpendicular to the stress plane may be used to determine both stress components. When the stress is off the acoustical axes, the shear and the difference of the normal stress components may be determined from the angular dependence of group velocities in the plane of stresses. Synthetic sets of experimental data corresponding to materials with different anisotropy and stress levels are used to check the applicability of the technique. The method is also verified experimentally. A high precision ultrasonic wave transmission technique is developed to measure angular dependence of ultrasonic velocities. Examples of stress determination from experimental velocity data are given. A method is presented for determination of velocities of ultrasonic waves propagating through the composite material with residual

  10. Effect of steam-flaked corn and soybeans on muscle and intramuscular fatty acid composition in Holstein calves.

    PubMed

    Zhang, Y Q; He, D C; Meng, Q X; Wang, D C

    2015-12-01

    This study aimed to evaluate the effects of steam-flaked corn grains and soybeans on muscle fatty acid composition. Thirty Holstein bull calves (21 ± 3 d) were divided into 3 groups according to birth date and BW and were randomly assigned to receive fresh milk and a commercial pelleted starter diet containing extruded corn and soybean (ECS), steam-flaked corn and soybean (SFCS), or ground corn and raw soybean (GCS). The calves were fed the designated diet from 3 to 13 wk of age, after which they were slaughtered. The supraspinatus (CTM), longissimus lumborum (RLM), and spinalis dorsi (ERM) were analyzed to determine the chemical and intramuscular fatty acid composition. The fatty acid composition of muscle and its deposition differed among calves fed different starter feeds. Medium-chain fatty acid levels of the RLM and CTM were greater in GCS-fed calves than in ECS- and SFCS-fed calves ( < 0.05). Extruded processing increased the content of linoleic, linolenic, and arachidonic acids of the RLM ( < 0.05). The palmitoleic and -vaccenic acid content of the ERM were greater in GCS-fed calves than in ECS- or SFCS-fed calves ( < 0.05). No significant differences were observed among the 3 diets with respect to the stearic, oleic, linoleic, -9 -11 CLA, or arachidonic acid content of the ERM ( > 0.05). The levels of -3 and -6 fatty acids were similar among the 3 groups; a lower -6:-3 PUFA ratio was observed in GCS-fed calves ( < 0.05). The cereal processing method of the calf starter feed had no significant effect on the chemical composition of the CTM, RLM, or ERM. Therefore, different methods of processing corn and soybean in calf starter feeds had no effect on the chemical composition of the RLM, CTM, or ERM but had a significant effect on the intramuscular fatty acid composition.

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

    PubMed

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

    2012-10-15

    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

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

    PubMed

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

    2012-10-15

    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.

  13. Determination of plutonium isotopic composition by gamma-ray spectroscopy

    SciTech Connect

    Sampson, T.E.; Hsue, S.T.; Parker, J.L.; Johnson, S.S.; Bowersox, D.F.

    1981-01-01

    We discuss the general approach, computerized data analysis methods, and results of measurements used to determine the isotopic composition of plutonium by gamma-ray spectroscopy. The simple techniques are designed to be applicable to samples of arbitrary size, geometry, age, chemical, and isotopic composition. The combination of the gamma spectroscopic measurement of isotopic composition coupled with calorimetric measurement of total sample power is shown to give a totally nondestructive determination of sample plutonium mass with a precision of 0.6% for 1000-g samples of PuO/sub 2/ with 12% /sup 240/Pu content. The precision of isotopic measurements depends upon many factors, including sample size, sample geometry, and isotopic content. Typical ranges are found to be /sup 238/Pu, 1 to 10%; /sup 239/Pu, 0.1 to 0.5%; /sup 240/Pu, 2 to 5%; /sup 241/Pu, 0.3 to 0.7%; /sup 242/Pu (determined by isotopic correlation); and /sup 241/Am, 0.2 to 10%.

  14. Potentiometric determination of free acidity in presence of hydrolysable ions and a sequential determination of hydrazine.

    PubMed

    Ganesh, S; Khan, Fahmida; Ahmed, M K; Pandey, S K

    2011-08-15

    A simple potentiometric method for the determination of free acidity in presence of hydrolysable ions and sequential determination of hydrazine is developed and described. Both free acid and hydrazine are estimated from the same aliquot. In this method, free acid is titrated with standard sodium carbonate solution after the metal ions in solutions are masked with EDTA. Once the end point for the free acid is determined at pH 3.0, an aliquot of formaldehyde is added to liberate the acid equivalent to hydrazine which is then titrated with the same standard sodium carbonate solution using an automatic titration system. The described method is simple, accurate and reproducible. This method is especially applicable to all ranges of nitric acid and heavy metal ion concentration relevant to Purex process used for nuclear fuel reprocessing. The overall recovery of nitric acid is 98.9% with 1.2% relative standard deviation. Hydrazine content has also been determined in the same aliquot with a recovery of nitric acid is 99% with 2% relative standard deviation. The major advantage of the method is that generation of corrosive analytical wastes containing oxalate or sulphate is avoided. Valuable metals like uranium and plutonium can easily be recovered from analytical waste before final disposal. PMID:21726724

  15. Automatic 1H-NMR Screening of Fatty Acid Composition in Edible Oils

    PubMed Central

    Castejón, David; Fricke, Pascal; Cambero, María Isabel; Herrera, Antonio

    2016-01-01

    In this work, we introduce an NMR-based screening method for the fatty acid composition analysis of edible oils. We describe the evaluation and optimization needed for the automated analysis of vegetable oils by low-field NMR to obtain the fatty acid composition (FAC). To achieve this, two scripts, which automatically analyze and interpret the spectral data, were developed. The objective of this work was to drive forward the automated analysis of the FAC by NMR. Due to the fact that this protocol can be carried out at low field and that the complete process from sample preparation to printing the report only takes about 3 min, this approach is promising to become a fundamental technique for high-throughput screening. To demonstrate the applicability of this method, the fatty acid composition of extra virgin olive oils from various Spanish olive varieties (arbequina, cornicabra, hojiblanca, manzanilla, and picual) was determined by 1H-NMR spectroscopy according to this protocol. PMID:26891323

  16. Automatic ¹H-NMR Screening of Fatty Acid Composition in Edible Oils.

    PubMed

    Castejón, David; Fricke, Pascal; Cambero, María Isabel; Herrera, Antonio

    2016-02-01

    In this work, we introduce an NMR-based screening method for the fatty acid composition analysis of edible oils. We describe the evaluation and optimization needed for the automated analysis of vegetable oils by low-field NMR to obtain the fatty acid composition (FAC). To achieve this, two scripts, which automatically analyze and interpret the spectral data, were developed. The objective of this work was to drive forward the automated analysis of the FAC by NMR. Due to the fact that this protocol can be carried out at low field and that the complete process from sample preparation to printing the report only takes about 3 min, this approach is promising to become a fundamental technique for high-throughput screening. To demonstrate the applicability of this method, the fatty acid composition of extra virgin olive oils from various Spanish olive varieties (arbequina, cornicabra, hojiblanca, manzanilla, and picual) was determined by ¹H-NMR spectroscopy according to this protocol. PMID:26891323

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

    PubMed

    Liu, Y; Longmore, R B

    1997-09-01

    Sandalwood (Santalum spicatum) seed oil, which occurs to about 50% of the weight of the seed kernels, contains 30-35% of total fatty acids (FA) as ximenynic acid (XMYA). This study was designed to obtain basic information on changes in tissue FA composition and on the metabolic fate of XMYA in mice fed a sandalwood seed oil (SWSO)-enriched diet. Female mice were randomly divided into three groups, each receiving different semisynthetic diets containing 5.2% (w/w) fat (standard laboratory diet), 15% canola oil, or 15% SWSO for 8 wk. The effects of SWSO as a dietary fat on the FA composition of adipose tissue, brain, and liver lipids were determined by analyses of FA methyl ester derivatives of extracted total lipid. The FA compositions of the liver and adipose tissue were markedly altered by the dietary fats, and mice fed on a SWSO-enriched diet were found to contain XMYA but only in low concentration (0.3-3%) in these tissues; XMYA was not detected in brain. Oleic acid was suggested to be a principal XMYA biotransformation product. The results were interpreted to suggest that the metabolism of XMYA may involve both biohydrogenation and oxidation reactions. PMID:9307938

  18. The Physico-Chemical Properties of Dietary Fibre Determine Metabolic Responses, Short-Chain Fatty Acid Profiles and Gut Microbiota Composition in Rats Fed Low- and High-Fat Diets

    PubMed Central

    Kulcinskaja, Evelina; Marungruang, Nittaya; Matziouridou, Chrysoula; Nilsson, Ulf; Stålbrand, Henrik; Nyman, Margareta

    2015-01-01

    The aim of this study was to investigate how physico-chemical properties of two dietary fibres, guar gum and pectin, affected weight gain, adiposity, lipid metabolism, short-chain fatty acid (SCFA) profiles and the gut microbiota in male Wistar rats fed either low- or high-fat diets for three weeks. Both pectin and guar gum reduced weight gain, adiposity, liver fat and blood glucose levels in rats fed a high-fat diet. Methoxylation degree of pectin (low, LM and high (HM)) and viscosity of guar gum (low, medium or high) resulted in different effects in the rats, where total blood and caecal amounts of SCFA were increased with guar gum (all viscosities) and with high methoxylated (HM) pectin. However, only guar gum with medium and high viscosity increased the levels of butyric acid in caecum and blood. Both pectin and guar gum reduced cholesterol, liver steatosis and blood glucose levels, but to varying extent depending on the degree of methoxylation and viscosity of the fibres. The medium viscosity guar gum was the most effective preparation for prevention of diet-induced hyperlipidaemia and liver steatosis. Caecal abundance of Akkermansia was increased with high-fat feeding and with HM pectin and guar gum of all viscosities tested. Moreover, guar gum had distinct bifidogenic effects independent of viscosity, increasing the caecal abundance of Bifidobacterium ten-fold. In conclusion, by tailoring the viscosity and possibly also the degree of methoxylation of dietary fibre, metabolic effects may be optimized, through a targeted modulation of the gut microbiota and its metabolites. PMID:25973610

  19. Ammonia gas sensing behavior of tanninsulfonic acid doped polyaniline-TiO₂ composite.

    PubMed

    Bairi, Venu Gopal; Bourdo, Shawn E; Sacre, Nicolas; Nair, Dev; Berry, Brian C; Biris, Alexandru S; Viswanathan, Tito

    2015-10-16

    A highly active tannin doped polyaniline-TiO₂ composite ammonia gas sensor was developed and the mechanism behind the gas sensing activity was reported for the first time. A tanninsulfonic acid doped polyaniline (TANIPANI)-titanium dioxide nanocomposite was synthesized by an in situ polymerization of aniline in the presence of tanninsulfonic acid and titanium dioxide nanoparticles. X-ray diffraction and thermogravimetric analysis were utilized to determine the incorporation of TiO₂ in TANIPANI matrix. UV-Visible and infrared spectroscopy studies provided information about the electronic interactions among tannin, polyaniline, and TiO₂. Scanning electron microscopy (SEM) along with energy dispersive X-ray spectroscopy (EDS) and atomic force microscopy (AFM) surface analysis techniques were used to investigate the metal oxide dispersions inside polyaniline matrix. Gas sensors were prepared by spin coating solutions of TANIPANI-TiO₂ and TANIPANI composites onto glass slides. Sensors were tested at three different concentrations (20 ppm, 40 ppm, and 60 ppm) of ammonia gas at ambient temperature conditions by measuring the changes in surface resistivity of the films with respect to time. Ammonia gas sensing plots are presented showing the response values, response times and recovery times. The TANIPANI-TiO₂ composite exhibited better response and shorter recovery times when compared to TANIPANI control and other polyaniline composites that have been reported in the literature. For the first time a proposed mechanism of gas sensing basing on the polaron band localization and its effects on the gas sensing behavior of polyaniline are reported.

  20. ADANSONIAN ANALYSIS AND DEOXYRIBONUCLEIC ACID BASE COMPOSITION OF SOME GRAM-NEGATIVE BACTERIA

    PubMed Central

    Colwell, R. R.; Mandel, M.

    1964-01-01

    Colwell, R. R. (Georgetown University, Washington, D.C.), and M. Mandel. Adansonian analysis and deoxyribonucleic acid base composition of some gram-negative bacteria. J. Bacteriol. 87:1412–1422. 1964.—The deoxyribonucleic acid (DNA) base compositions and S values for a minimum of 134 coded properties were determined for representative cultures of the genera Pseudomonas, Xanthomonas, Aeromonas, Vibrio, Aerobacter, Escherichia, Alcaligenes, and Flavobacterium. Those cultures having a high degree of similarity by the criterion of numerical taxonomy were found to have similar DNA base compositions. The relative affinities of clusters of cultures suggest taxonomic relations. Eleven species of Xanthomonas might be a single species, and V. metschnikovii was shown to be more closely related to enteric bacteria than to other vibrios which, in turn, were found to be like pseudomonads. Aeromonas was found to be intermediate in similarity to enterics and pseudomonads and divisible into at least two, but possibly three, species. F. aquatile was unlike any of the other organisms studied, and its DNA also differed greatly in composition from other representatives of the genus. PMID:14188722

  1. Influences of acidic reaction and hydrolytic conditions on monosaccharide composition analysis of acidic, neutral and basic polysaccharides.

    PubMed

    Wang, Qing-Chi; Zhao, Xia; Pu, Jiang-Hua; Luan, Xiao-Hong

    2016-06-01

    Monosaccharide composition analysis is important for structural characterization of polysaccharides. To investigate the influences of acidic reaction and hydrolytic conditions on monosaccharide composition analysis of polysaccharides, we chose alginate, starch, chitosan and chondroitin sulfate as representative of acidic, neutral, basic and complex polysaccharides to compare the release degree of monosaccharides under different hydrolytic conditions. The hydrolysis stability of 10 monosaccharide standards was also explored. Results showed that the basic sugars were hard to release but stable, the acidic sugars (uronic acids) were easy to release but unstable, and the release and stability of neutral sugars were in between acidic and basic sugars. In addition, the hydrolysis process was applied to monosaccharide composition analysis of Hippocampus trimaculatus polysaccharide and the appropriate hydrolytic condition was accorded with that of the above four polysaccharides. Thus, different hydrolytic conditions should be used for the monosaccharide composition analysis of polysaccharides based on their structural characteristics. PMID:27083372

  2. Electrophoretic deposition of tannic acid-polypyrrolidone films and composites.

    PubMed

    Luo, Dan; Zhang, Tianshi; Zhitomirsky, Igor

    2016-05-01

    Thin films of polyvinylpyrrolidone (PVP)-tannic acid (TA) complexes were prepared by a conceptually new strategy, based on electrophoretic deposition (EPD). Proof of concept investigations involved the analysis of the deposition yield, FTIR and UV-vis spectroscopy of the deposited material, and electron microscopy studies. The analysis of the deposition mechanism indicated that the limitations of the EPD in the deposition of small phenolic molecules, such as TA, and electrically neutral polymers, similar to PVP, containing hydrogen-accepting carbonyl groups, can be avoided. The remarkable adsorption properties of TA and film forming properties of the PVP-TA complexes allowed for the EPD of materials of different types, such as huntite mineral platelets and hydrotalcite clay particles, TiO2 and MnO2 oxide nanoparticles, multiwalled carbon nanotubes, TiN and Pd nanoparticles. Moreover, PVP-TA complexes were used for the co-deposition of different materials and formation of composite films. In another approach, TA was used as a capping agent for the hydrothermal synthesis of ZnO nanorods, which were then deposited by EPD using PVP-TA complexes. The fundamental adsorption and interaction mechanisms of TA involved chelation of metal atoms on particle surfaces with galloyl groups, π-π interactions and hydrogen bonding. The films prepared by EPD can be used for various applications, utilizing functional properties of TA, PVP, inorganic and organic materials of different types and their composites.

  3. Electrophoretic deposition of tannic acid-polypyrrolidone films and composites.

    PubMed

    Luo, Dan; Zhang, Tianshi; Zhitomirsky, Igor

    2016-05-01

    Thin films of polyvinylpyrrolidone (PVP)-tannic acid (TA) complexes were prepared by a conceptually new strategy, based on electrophoretic deposition (EPD). Proof of concept investigations involved the analysis of the deposition yield, FTIR and UV-vis spectroscopy of the deposited material, and electron microscopy studies. The analysis of the deposition mechanism indicated that the limitations of the EPD in the deposition of small phenolic molecules, such as TA, and electrically neutral polymers, similar to PVP, containing hydrogen-accepting carbonyl groups, can be avoided. The remarkable adsorption properties of TA and film forming properties of the PVP-TA complexes allowed for the EPD of materials of different types, such as huntite mineral platelets and hydrotalcite clay particles, TiO2 and MnO2 oxide nanoparticles, multiwalled carbon nanotubes, TiN and Pd nanoparticles. Moreover, PVP-TA complexes were used for the co-deposition of different materials and formation of composite films. In another approach, TA was used as a capping agent for the hydrothermal synthesis of ZnO nanorods, which were then deposited by EPD using PVP-TA complexes. The fundamental adsorption and interaction mechanisms of TA involved chelation of metal atoms on particle surfaces with galloyl groups, π-π interactions and hydrogen bonding. The films prepared by EPD can be used for various applications, utilizing functional properties of TA, PVP, inorganic and organic materials of different types and their composites. PMID:26878711

  4. Effect of Gallic acid on mechanical and water barrier properties of zein-oleic acid composite films.

    PubMed

    Masamba, Kingsley; Li, Yue; Hategekimana, Joseph; Liu, Fei; Ma, Jianguo; Zhong, Fang

    2016-05-01

    In this study, the effect of gallic acid on mechanical and water barrier properties of zein-oleic acid 0-4 % composite films was investigated. Molecular weight distribution analysis was carried out to confirm gallic acid induced cross linking through change in molecular weight in fraction containing zein proteins. Results revealed that gallic acid treatment increased tensile strength from 17.9 MPa to 26.0 MPa, decreased water vapour permeability from 0.60 (g mm m(-2) h(-1) kPa(-1)) to 0.41 (g mm m(-2) h(-1) kPa(-1)), increased solubility from 6.3 % to 10.2 % and marginally increased elongation at break from 3.7 % to 4.2 % in zein films only. However, gallic acid treatment in zein-oleic composite films did not significantly influence mechanical and water barrier properties and in most instances irrespective of oleic acid concentration, the properties were negatively affected. Results from scanning electron microscopy showed that both gallic acid treated and untreated zein films and composite films containing 3 % oleic acid had a compact and homogeneous structure while those containing 4 % oleic acid had inhomogeneous structure. The findings have demonstrated that gallic acid treatment can significantly improve mechanical and water barrier properties especially in zein films only as opposed to when used in composite films using zein and oleic acid. PMID:27407188

  5. Effect of Gallic acid on mechanical and water barrier properties of zein-oleic acid composite films.

    PubMed

    Masamba, Kingsley; Li, Yue; Hategekimana, Joseph; Liu, Fei; Ma, Jianguo; Zhong, Fang

    2016-05-01

    In this study, the effect of gallic acid on mechanical and water barrier properties of zein-oleic acid 0-4 % composite films was investigated. Molecular weight distribution analysis was carried out to confirm gallic acid induced cross linking through change in molecular weight in fraction containing zein proteins. Results revealed that gallic acid treatment increased tensile strength from 17.9 MPa to 26.0 MPa, decreased water vapour permeability from 0.60 (g mm m(-2) h(-1) kPa(-1)) to 0.41 (g mm m(-2) h(-1) kPa(-1)), increased solubility from 6.3 % to 10.2 % and marginally increased elongation at break from 3.7 % to 4.2 % in zein films only. However, gallic acid treatment in zein-oleic composite films did not significantly influence mechanical and water barrier properties and in most instances irrespective of oleic acid concentration, the properties were negatively affected. Results from scanning electron microscopy showed that both gallic acid treated and untreated zein films and composite films containing 3 % oleic acid had a compact and homogeneous structure while those containing 4 % oleic acid had inhomogeneous structure. The findings have demonstrated that gallic acid treatment can significantly improve mechanical and water barrier properties especially in zein films only as opposed to when used in composite films using zein and oleic acid.

  6. Effects of dietary conjugated linoleic acid on fatty acid composition and cholesterol content of hen egg yolks.

    PubMed

    Szymczyk, Beata; Pisulewski, Paweł M

    2003-07-01

    The main objectives of the present study were to determine the effect of dietary conjugated linoleic acid (CLA) isomers on the fatty acid composition and cholesterol content of egg-yolk lipids. Forty-five 25-week-old laying hens were randomly distributed into five groups of nine hens each and maintained in individual laying cages, throughout 12 weeks of the experiment. They were assigned to the five treatments that consisted of commercial layer diets containing 0, 5, 10, 15 or 20 g pure CLA/kg. Feed intake of hens varied little and insignificantly. Egg mass was uniformly lower (P<0.05) in the hens fed the CLA-enriched diets. Feed conversion efficiency, when expressed per kg eggs, was impaired (P<0.05), although without obvious relation to the dietary CLA concentration. Feeding the CLA-enriched diets resulted in gradually increasing deposition of CLA isomers (P<0.01) in egg-yolk lipids. Saturated fatty acids were increased (P<0.01) and monounsaturated fatty acids decreased (P<0.01). Polyunsaturated fatty acids (PUFA), when expressed as non-CLA PUFA, were also significantly decreased (P<0.01). The most striking effects (P<0.01) were observed for palmitic (16 : 0) and stearic (18 : 0) acids, which increased from 23.6 to 34 % and from 7.8 to 18 %, respectively. On the other hand, oleic acid (18 : 1n-9) decreased from 45.8 to 24.3 %. Among non-CLA PUFA, linoleic (18 : 2n-6) and alpha-linolenic (18 : 3n-3) acids were strongly (P<0.01) decreased, from 14.2 to 7.7 % and from 1.3 to 0.3 %, respectively. The same was true for arachidonic (20:4n-6) and docosahexaenoic (22 : 6n-3) acids. The cholesterol content of egg yolks, when expressed in mg/g yolk, was not affected by the dietary CLA concentrations. In conclusion, unless the adverse effects of CLA feeding to laying hens on the fatty acid profile of egg yolks are eliminated, the CLA-enriched eggs cannot be considered functional food products. PMID:12844380

  7. Determination of water-soluble forms of oxalic and formic acids in soils by ion chromatography

    NASA Astrophysics Data System (ADS)

    Karicheva, E.; Guseva, N.; Kambalina, M.

    2016-03-01

    Carboxylic acids (CA) play an important role in the chemical composition origin of soils and migration of elements. The content of these acids and their salts is one of the important characteristics for agrochemical, ecological, ameliorative and hygienic assessment of soils. The aim of the article is to determine water-soluble forms of same carboxylic acids — (oxalic and formic acids) in soils by ion chromatography with gradient elution. For the separation and determination of water-soluble carboxylic acids we used reagent-free gradient elution ion-exchange chromatography ICS-2000 (Dionex, USA), the model solutions of oxalate and formate ions, and leachates from soils of the Kola Peninsula. The optimal gradient program was established for separation and detection of oxalate and formate ions in water solutions by ion chromatography. A stability indicating method was developed for the simultaneous determination of water-soluble organic acids in soils. The method has shown high detection limits such as 0.03 mg/L for oxalate ion and 0.02 mg/L for formate ion. High signal reproducibility was achieved in wide range of intensities which correspond to the following ion concentrations: from 0.04 mg/g to 10 mg/L (formate), from 0.1 mg/g to 25 mg/L (oxalate). The concentration of formate and oxalate ions in soil samples is from 0.04 to 0.9 mg/L and 0.45 to 17 mg/L respectively.

  8. A comparison of the physicochemical properties and fatty acid composition of indaiá (Attalea dubia) and Babassu (Orbignya phalerata) oils.

    PubMed

    Ferreira, Bianca Silva; Faza, Lara Pereira; Le Hyaric, Mireille

    2012-01-01

    The physicochemical properties and fatty acid composition of Attalea dubia (Mart.) Burret (indaiá) seed oil were investigated. The oil was extracted in a soxhlet apparatus using petroleum ether and evaluated for iodine, acid, peroxide, ester, and saponification values. The oil was also analyzed using infrared and nuclear magnetic resonance spectroscopy. The fatty acid profile of the oil was determined by GC-MS. For each analysis indaiá oil was compared to Orbignya phalerata (babassu) oil. The two oils appeared to be very similar in their fatty acid composition, in which lauric acid (the most abundant), myristic acid, caprylic acid, and capric acid were the four main fatty acids detected. The unsaturated fatty acids content was lower for indaiá oil (5.8%) than for babassu oil (9.4%). The results suggest that indaiá palm tree could be cultivated as a new source of vegetable oil with potential for food and cosmetic industries.

  9. A comparison of the physicochemical properties and fatty acid composition of indaiá (Attalea dubia) and Babassu (Orbignya phalerata) oils.

    PubMed

    Ferreira, Bianca Silva; Faza, Lara Pereira; Le Hyaric, Mireille

    2012-01-01

    The physicochemical properties and fatty acid composition of Attalea dubia (Mart.) Burret (indaiá) seed oil were investigated. The oil was extracted in a soxhlet apparatus using petroleum ether and evaluated for iodine, acid, peroxide, ester, and saponification values. The oil was also analyzed using infrared and nuclear magnetic resonance spectroscopy. The fatty acid profile of the oil was determined by GC-MS. For each analysis indaiá oil was compared to Orbignya phalerata (babassu) oil. The two oils appeared to be very similar in their fatty acid composition, in which lauric acid (the most abundant), myristic acid, caprylic acid, and capric acid were the four main fatty acids detected. The unsaturated fatty acids content was lower for indaiá oil (5.8%) than for babassu oil (9.4%). The results suggest that indaiá palm tree could be cultivated as a new source of vegetable oil with potential for food and cosmetic industries. PMID:22593692

  10. Whole-body amino acid composition of adult fancy ranchu goldfish (Carassius auratus).

    PubMed

    Snellgrove, Donna L; Alexander, Lucille G

    2011-10-01

    Aqua feeds should be formulated to provide complete and balanced nutrition to achieve optimal health and growth in fish, including adequate levels of essential amino acids (EAA). There are few or no data relating to the EAA requirements for ornamental fish species, with the majority of quantitative data for these nutrients being available for commercially farmed fish. The determination of EAA requirements is usually established through dose-response studies, which can be costly and time consuming, especially if determining the requirement for many amino acids (AA). An alternative method for predicting the EAA of fish, which is also relatively fast and inexpensive, is the assessment of whole-body AA composition. A total of eight goldfish with a mean wet weight of 34.2 (SEM 1.4) g were obtained as a result of a routine cull by breeders. The fish were freeze-dried and AA was content analysed by hydrolysis or performic 'acid' oxidation. EAA values ranged between 0.97 (SEM 0.02) for tryptophan and 7.9 (SEM 0.14) for lysine (g/100 g AA). Compositional data were also used to estimate the essential amino acid ratios of these fish. The findings are in agreement with those for juvenile common goldfish, suggesting that there are no differences in whole-body AA composition between juvenile and adult, or fancy and common goldfish. However, these indices do not provide a quantitative total amount of each AA required by the fish, but can be used proportionally to provide guidelines to formulate diets for ornamental species. PMID:22005403

  11. Whole-body amino acid composition of adult fancy ranchu goldfish (Carassius auratus).

    PubMed

    Snellgrove, Donna L; Alexander, Lucille G

    2011-10-01

    Aqua feeds should be formulated to provide complete and balanced nutrition to achieve optimal health and growth in fish, including adequate levels of essential amino acids (EAA). There are few or no data relating to the EAA requirements for ornamental fish species, with the majority of quantitative data for these nutrients being available for commercially farmed fish. The determination of EAA requirements is usually established through dose-response studies, which can be costly and time consuming, especially if determining the requirement for many amino acids (AA). An alternative method for predicting the EAA of fish, which is also relatively fast and inexpensive, is the assessment of whole-body AA composition. A total of eight goldfish with a mean wet weight of 34.2 (SEM 1.4) g were obtained as a result of a routine cull by breeders. The fish were freeze-dried and AA was content analysed by hydrolysis or performic 'acid' oxidation. EAA values ranged between 0.97 (SEM 0.02) for tryptophan and 7.9 (SEM 0.14) for lysine (g/100 g AA). Compositional data were also used to estimate the essential amino acid ratios of these fish. The findings are in agreement with those for juvenile common goldfish, suggesting that there are no differences in whole-body AA composition between juvenile and adult, or fancy and common goldfish. However, these indices do not provide a quantitative total amount of each AA required by the fish, but can be used proportionally to provide guidelines to formulate diets for ornamental species.

  12. Determination of organic acid impurities in lactic acid obtained by fermentation of sugarcane juice.

    PubMed

    Qureshi, Mohd Shadbar; Bhongale, Sunil S; Thorave, Archana K

    2011-10-01

    Lactic acid produced by fermentation process mostly contains a number of aliphatic carboxylic acids as impurities. In this work, carboxylic acid impurities in lactic acid samples from a number of sources were determined at ppm levels. A simple HPLC method was developed that utilized a new generation polar embedded reverse phase, 20mM phosphate buffer at pH 2.20 (±0.05) and UV detection at 210 nm. The method enabled quantitative analysis of the above acids in lactic acid matrix. The experimental conditions for column temperature, mobile phase pH and flow rate were optimized. A detailed validation of the method was performed for linearity, precision, accuracy, selectivity, limit of detection (LOD), limit of quantitation (LOQ), ruggedness and repeatability and reproducibility (R&R).

  13. Determination of acidity constants of enolisable compounds by capillary electrophoresis.

    PubMed

    Mofaddel, N; Bar, N; Villemin, D; Desbène, P L

    2004-10-01

    Research on the structure-activity relationships of molecules with acidic carbon atoms led us to undertake a feasibility study on the determination of their acidity constants by capillary electrophoresis (CE). The studied molecules had diverse structures and were tetronic acid, acetylacetone, diethylmalonate, Meldrum's acid, 3-methylrhodanine, nitroacetic acid ethyl ester, pyrimidine-2,4,6-trione, 3-oxo-3-phenylpropionic acid ethyl ester, 1-phenylbutan-1,3-dione, 5,5-dimethylcyclohexan-1,3-dione and homophthalic anhydride. The p Ka range explored by CE was therefore very large (from 3 to 12) and p Ka values near 12 were evaluated by mathematical extrapolations. The analyses were carried out in CZE mode using a fused silica capillary grafted (or not) with hexadimethrine. Owing to the electrophoretic behaviour of these compounds according to the pH, their acidity constants could be evaluated and appeared in perfect agreement with the literature data obtained, a few decades ago, by means of potentiometry, spectrometry or conductimetry. The p Ka of homophthalic anhydride and 3-methylrhodanine were evaluated for the first time.

  14. Amino acid compositions in heated carbonaceous chondrites and their compound-specific nitrogen isotopic ratios

    NASA Astrophysics Data System (ADS)

    Chan, Queenie Hoi Shan; Chikaraishi, Yoshito; Takano, Yoshinori; Ogawa, Nanako O.; Ohkouchi, Naohiko

    2016-01-01

    A novel method has been developed for compound-specific nitrogen isotope compositions with an achiral column which was previously shown to offer high precision for nitrogen isotopic analysis. We applied the method to determine the amino acid contents and stable nitrogen isotopic compositions of individual amino acids from the thermally metamorphosed (above 500 °C) Antarctic carbonaceous chondrites Ivuna-like (CI)1 (or CI-like) Yamato (Y) 980115 and Ornans-like (CO)3.5 Allan Hills (ALH) A77003 with the use of gas chromatography/combustion/isotope ratio mass spectrometry. ALHA77003 was deprived of amino acids due to its extended thermal alteration history. Amino acids were unambiguously identified in Y-980115, and the δ15N values of selected amino acids (glycine +144.8 ‰; α-alanine +121.2 ‰) are clearly extraterrestrial. Y-980115 has experienced an extended period of aqueous alteration as indicated by the presence of hydrous mineral phases. It has also been exposed to at least one post-hydration short-lived thermal metamorphism. Glycine and alanine were possibly produced shortly after the accretion event of the asteroid parent body during the course of an extensive aqueous alteration event and have abstained from the short-term post-aqueous alteration heating due to the heterogeneity of the parent body composition and porosity. These carbonaceous chondrite samples are good analogs that offer important insights into the target asteroid Ryugu of the Hayabusa-2 mission, which is a C-type asteroid likely composed of heterogeneous materials including hydrated and dehydrated minerals.

  15. Thoron-meso-tartaric acid system for determination of thorium

    USGS Publications Warehouse

    Fletcher, M.H.; Grimaldi, F.S.; Jenkins, L.B.

    1957-01-01

    In the spectrophotometric determination of thorium with thoron, mesotartaric acid is used as a masking reagent for zirconium. The effects of different experimental variables such as the concentrations of the reagents, time, and temperature, and the behavior of 35 ions which might be present in thorium ores are discussed. A dilution procedure is given for the direct determination of thorium in zircon (ZrSiO4) that is also generally applicable to other materials.

  16. 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 ...

  17. Effects of heating on composition, degree of darkness, and stacking nanostructure of soil humic acids.

    PubMed

    Katsumi, Naoya; Yonebayashi, Koyo; Okazaki, Masanori

    2016-01-15

    Wildfires and prescribed burning can affect both the quality and the quantity of organic matter in soils. In this study, we investigated qualitative and quantitative changes of soil humic substances in two different soils (an Entisol from a paddy field and an Inceptisol from a cedar forest) under several controlled heating conditions. Soil samples were heated in a muffle furnace at 200, 250, or 300 °C for 1, 3, 5, or 12h. The humic acid and fulvic acid contents of the soil samples prior to and after heating were determined. The degree of darkness, elemental composition, carbon and nitrogen stable isotope ratios, (13)C nuclear magnetic resonance spectra, and X-ray diffraction patterns of humic acids extracted from the soils before and after heating were measured. The proportion of humic acids in total carbon decreased with increasing heating time at high temperature (300 °C), but increased with increasing heating time at ≤ 250 °C. The degree of darkness of the humic acids increased with increasing heating time and temperature. During darkening, the H/C atomic ratios, the proportion of aromatic C, and the carbon and nitrogen stable isotope ratios increased, whereas the proportions of alkyl C and O-alkyl C decreased. X-ray diffraction analysis verified that a stacking nanostructure developed by heating. Changes in the chemical structure of the humic acids from the heated soils depended on the type of soil. The major structural components of the humic acids from the heated Entisol were aromatic C and carboxylic C, whereas aliphatic C, aromatic C, and carboxylic C structural components were found in the humic acids from the heated Inceptisol. These results suggest that the heat-induced changes in the chemical structure of the humic acids depended on the source plant.

  18. Effects of heating on composition, degree of darkness, and stacking nanostructure of soil humic acids.

    PubMed

    Katsumi, Naoya; Yonebayashi, Koyo; Okazaki, Masanori

    2016-01-15

    Wildfires and prescribed burning can affect both the quality and the quantity of organic matter in soils. In this study, we investigated qualitative and quantitative changes of soil humic substances in two different soils (an Entisol from a paddy field and an Inceptisol from a cedar forest) under several controlled heating conditions. Soil samples were heated in a muffle furnace at 200, 250, or 300 °C for 1, 3, 5, or 12h. The humic acid and fulvic acid contents of the soil samples prior to and after heating were determined. The degree of darkness, elemental composition, carbon and nitrogen stable isotope ratios, (13)C nuclear magnetic resonance spectra, and X-ray diffraction patterns of humic acids extracted from the soils before and after heating were measured. The proportion of humic acids in total carbon decreased with increasing heating time at high temperature (300 °C), but increased with increasing heating time at ≤ 250 °C. The degree of darkness of the humic acids increased with increasing heating time and temperature. During darkening, the H/C atomic ratios, the proportion of aromatic C, and the carbon and nitrogen stable isotope ratios increased, whereas the proportions of alkyl C and O-alkyl C decreased. X-ray diffraction analysis verified that a stacking nanostructure developed by heating. Changes in the chemical structure of the humic acids from the heated soils depended on the type of soil. The major structural components of the humic acids from the heated Entisol were aromatic C and carboxylic C, whereas aliphatic C, aromatic C, and carboxylic C structural components were found in the humic acids from the heated Inceptisol. These results suggest that the heat-induced changes in the chemical structure of the humic acids depended on the source plant. PMID:26398447

  19. Determination of fatty acid profile in ram spermatozoa and seminal plasma.

    PubMed

    Díaz, R; Torres, M A; Bravo, S; Sanchez, R; Sepúlveda, N

    2016-08-01

    Fatty acids are important in male reproductive function because they are associated with membrane fluidity, acrosome reaction, sperm motility and viability, but limited information exists about the fatty acid profile of ram semen. Our aim was to determine the fatty acid composition in ram spermatozoa and seminal plasma. Sixty ejaculates were obtained from three ram (20 ejaculates/ram) using artificial vagina. Ram spermatozoa (RS) and seminal plasma (SP) were separated using centrifugation, and the fatty acids were analysed by gas chromatography. Total lipids obtained in ram spermatozoa were 1.8% and 1.6% in seminal plasma. Saturated fatty acid (SFA) was proportionally major in SP (66.6%) that RS (49.9%). The highest proportions of SFA corresponded to C4:0 (RS = 16.3% and SP = 28.8%) and C16:0 (RS = 16.3% and PS = 20%). The most important unsaturated fatty acid (UFA) was docosahexaenoic acid (DHA), 44.9% in RS and 31.5% in SP. The profile of fatty acid and their proportions showed differences between spermatozoa and seminal plasma.

  20. Morphology and Composition of Structured, Phase-Separated Behenic Acid-Perfluorotetradecanoic Acid Monolayer Films.

    PubMed

    Rehman, Jeveria; Araghi, Hessamaddin Younesi; He, Anqiang; Paige, Matthew F

    2016-05-31

    The phase separation of immiscible surfactants in mixed monolayer films provides an approach to physically manipulate important properties of thin films, including surface morphology, microscale composition, and mechanical properties. In this work, we predict, based upon existing miscibility studies and their thermodynamic underpinnings described in the literature, the miscibility and film morphology of mixed monolayers comprised of behenic acid (C21H43COOH) and perfluorotetradecanoic acid (C13F27COOH) in various molar ratios. Predictions are tested using a combination of experimental surface characterization methods for probing miscibility and film morphology at the solid/air and air/water interfaces. Film components were immiscible and phase-separated into chemically well-defined domains under a variety of experimental conditions, with monolayer morphology consistent with initial predictions. The extensibility of these basic predictions to other systems is discussed in the context of using these works for different perfluorinated surfactant molecules. PMID:27163482

  1. Essential fatty acid intake and serum fatty acid composition among adolescent girls in central Mozambique.

    PubMed

    Freese, Riitta; Korkalo, Liisa; Vessby, Bengt; Tengblad, Siv; Vaara, Elina M; Hauta-alus, Helena; Selvester, Kerry; Mutanen, Marja

    2015-04-14

    Many African diets are low in fat but are currently changing because of nutrition transition. We studied fat and fatty acid (FA) intake and the essential fatty acid (EFA) status of adolescent girls (aged 14-19 years, n 262) in Zambezia Province, central Mozambique. A cross-sectional study was carried out in a city as well as in the towns and rural villages of a coastal and an inland district. Dietary intake and FA sources were studied in a 24 h dietary recall. FA compositions of cholesteryl esters and phospholipids of non-fasting serum samples were analysed by GLC. Fat intake was low (13-18 % of energy) in all areas. Coconut and palm oil were the main sources of fat, and soyabean oil and maize were the main sources of PUFA. Compared to Food and Agriculture Organization/WHO 2010 recommendations, intake of linoleic acid (LA, 18 : 2n-6) was inadequate in the coastal district, and intakes of n-3 PUFA were inadequate in all areas. FA compositions of serum lipids differed between areas. The proportions of LA tended to be highest in the city and lowest in the rural areas. The phospholipid mead (20 : 3n-9):arachidonic acid (20 : 4n-6) ratio did not indicate EFA insufficiency. LA proportions in phospholipids were low, but those of long-chain n-6 and n-3 PUFA were high in comparison with Western adolescents. To conclude, fat sources, FA intake and EFA status differed between adolescent girls living in different types of communities. Fat intake was low, but EFA insufficiency was not indicated.

  2. Essential fatty acid intake and serum fatty acid composition among adolescent girls in central Mozambique.

    PubMed

    Freese, Riitta; Korkalo, Liisa; Vessby, Bengt; Tengblad, Siv; Vaara, Elina M; Hauta-alus, Helena; Selvester, Kerry; Mutanen, Marja

    2015-04-14

    Many African diets are low in fat but are currently changing because of nutrition transition. We studied fat and fatty acid (FA) intake and the essential fatty acid (EFA) status of adolescent girls (aged 14-19 years, n 262) in Zambezia Province, central Mozambique. A cross-sectional study was carried out in a city as well as in the towns and rural villages of a coastal and an inland district. Dietary intake and FA sources were studied in a 24 h dietary recall. FA compositions of cholesteryl esters and phospholipids of non-fasting serum samples were analysed by GLC. Fat intake was low (13-18 % of energy) in all areas. Coconut and palm oil were the main sources of fat, and soyabean oil and maize were the main sources of PUFA. Compared to Food and Agriculture Organization/WHO 2010 recommendations, intake of linoleic acid (LA, 18 : 2n-6) was inadequate in the coastal district, and intakes of n-3 PUFA were inadequate in all areas. FA compositions of serum lipids differed between areas. The proportions of LA tended to be highest in the city and lowest in the rural areas. The phospholipid mead (20 : 3n-9):arachidonic acid (20 : 4n-6) ratio did not indicate EFA insufficiency. LA proportions in phospholipids were low, but those of long-chain n-6 and n-3 PUFA were high in comparison with Western adolescents. To conclude, fat sources, FA intake and EFA status differed between adolescent girls living in different types of communities. Fat intake was low, but EFA insufficiency was not indicated. PMID:25772191

  3. Experimental determination of material constants of a hybrid composite laminate

    SciTech Connect

    Ihekweazu, S.N.; Lari, S.B.; Unanwa, C.O.

    1999-07-01

    This paper discusses the results of the experimental study that was conducted in order to determine the material properties of a hybrid composite laminate made from Fiberite material MXM-7714/120 (a fabric prepreg consisting of woven Kevlar{reg_sign} 49 reinforcement impregnated with Fiberite 250 F (121 C) curing 7714 epoxy resin) and HYE-2448AIE (a 250 F (121 C) curing epoxy resin impregnated unidirectional graphite tape). First, each of the materials that comprise the hybrid laminate was fabricated separately according to ASTM-D-3039 specification in order to determine their material properties. The materials were then hybridized and the properties were determined. Data from this experiment reveal that a new class of material that can meet desired specifications can be created through hybridization. The data also revealed that the properties of the materials bonded together as a hybrid complement the properties of the constituent members of the hybrid.

  4. Lidar determination of the composition of atmosphere aerosols

    NASA Technical Reports Server (NTRS)

    Wright, M. L.

    1980-01-01

    Theoretical and experimental studies of the feasibility of using DIfferential SCatter (DISC) lidar to measure the composition of atmospheric aerosols are described. This technique involves multiwavelength measurements of the backscatter cross section of aerosols in the middle infrared, where a number of materials display strong restrahlen features that significantly modulate the backscatter spectrum. The theoretical work indicates that a number of materials of interest, including sulfuric acid, ammonium sulfate, and silicates, can be discriminated among with a CO2 lidar. An initial evaluation of this procedure was performed in which cirrus clouds and lower altitude tropospheric aerosols were developed. The observed ratio spectrum of the two types of aerosol displays structure that is in crude accord with theoretical expectations.

  5. Fatty acid composition of an oral load affects chylomicron size in human subjects.

    PubMed

    Sakr, S W; Attia, N; Haourigui, M; Paul, J L; Soni, T; Vacher, D; Girard-Globa, A

    1997-01-01

    HDL-phospholipids are determinants in reverse cholesterol transport. They are mostly derived from triacylglycerol (TG)-rich lipoproteins. Chylomicron size is important, therefore, because it is related to the ratio surface phospholipids: core TG and, thus, determines the availability of postprandial phospholipids for transfer to HDL. Eleven healthy young women each ingested four different fat loads supplemented with retinyl palmitate and containing 60 g sunflower oil (SO), oleic-sunflower oil (OSO), mixed oil (MO; (g/kg) linoleic acid 480, oleic acid 380, linolenic acid 13) or beef tallow (BT). At the peak of TG absorption for all loads (4 h) chylomicron diameters, determined by agarose-gel filtration, were larger after SO compared with OSO (P < 0.05) and BT (P = 0.06) and after MO compared with BT (P < 0.05). At 6 h chylomicron size was larger after the vegetable oils compared with BT (P < 0.05 in each case). After each fat load chylomicron size decreased at 6 and 8 h compared with that at 4 h (P < 0.05) except for OSO. Retinyl ester and TG concentrations were lower in chylomicrons after BT than after the other fats but not in the chylomicron-free serum (containing chylomicron remnants), suggesting absorption in the form of very small particles. Compared with the fasting value, the concentration of the Svedberg unit of flotation 20-400 fraction, which contains VLDL and chylomicron remnants, was lower 8 h after MO, the only fat to contain significant amounts of linolenic acid. We conclude that chylomicron size is dependent on the fatty acid composition of ingested fats and the time-course of digestion, being larger for polyunsaturated fatty acid-rich fats and in the early phase of digestion. On the basis of retinyl ester concentration there were no differences between fats in chylomicron-remnant clearance.

  6. Genetic variation of six desaturase genes in flax and their impact on fatty acid composition.

    PubMed

    Thambugala, Dinushika; Duguid, Scott; Loewen, Evelyn; Rowland, Gordon; Booker, Helen; You, Frank M; Cloutier, Sylvie

    2013-10-01

    Flax (Linum usitatissimum L.) is one of the richest plant sources of omega-3 fatty acids praised for their health benefits. In this study, the extent of the genetic variability of genes encoding stearoyl-ACP desaturase (SAD), and fatty acid desaturase 2 (FAD2) and 3 (FAD3) was determined by sequencing the six paralogous genes from 120 flax accessions representing a broad range of germplasm including some EMS mutant lines. A total of 6 alleles for sad1 and sad2, 21 for fad2a, 5 for fad2b, 15 for fad3a and 18 for fad3b were identified. Deduced amino acid sequences of the alleles predicted 4, 2, 3, 4, 6 and 7 isoforms, respectively. Allele frequencies varied greatly across genes. Fad3a, with 110 SNPs and 19 indels, and fad3b, with 50 SNPs and 5 indels, showed the highest levels of genetic variations. While most of the SNPs and all the indels were silent mutations, both genes carried nonsense SNP mutations resulting in premature stop codons, a feature not observed in sad and fad2 genes. Some alleles and isoforms discovered in induced mutant lines were absent in the natural germplasm. Correlation of these genotypic data with fatty acid composition data of 120 flax accessions phenotyped in six field experiments revealed statistically significant effects of some of the SAD and FAD isoforms on fatty acid composition, oil content and iodine value. The novel allelic variants and isoforms identified for the six desaturases will be a resource for the development of oilseed flax with unique and useful fatty acid profiles.

  7. Diet preferences for specific fatty acids and their effect on composition of fat reserves in migratory Red-eyed Vireos (Vireo olivaceous).

    PubMed

    Pierce, Barbara J; McWilliams, Scott R; Place, Allen R; Huguenin, Michael A

    2004-08-01

    Fatty acid composition of body fat in birds often differs between bird species and between seasons, and changes in diet may be responsible for this variation. We tested two related hypotheses using Red-eyed Vireos, a long-distance migratory songbird: (1) birds prefer diets with certain fatty acids, and (2) fatty acid composition of the diet primarily determines the composition of lipid reserves. During paired-choice experiments, vireos preferred semi-synthetic diets with triolein (81% digestive extraction efficiency) over diets with tristearin (54% digestive extraction efficiency) and, in general, ate more when offered diets with unsaturated fats compared to saturated fats. These results demonstrate that vireos can discriminate between diets differing only in fatty acid composition and prefer diets with long-chain unsaturated fatty acids. When vireos were fed one of two diets for 1 month, the primary fatty acids in each diet also predominated in the tissues of birds fed each diet. However, some fatty acids that were absent in the diet occurred in bird tissues (e.g., 22:4, 22:5) suggesting that selective metabolism of fatty acids along with diet composition determine the fatty acid composition of lipid reserves in migratory birds. PMID:15369840

  8. Determination of Proximate, Minerals, Vitamin and Anti-Nutrients Composition of Solanum verbascifolium Linn.

    NASA Astrophysics Data System (ADS)

    Sam, S. M.; Udosen, I. R.; Mensah, S. I.

    2012-07-01

    The proximate, minerals, vitamins and anti-nutrients composition of Solanum verbascifolium Linn were determined. The proximate composition showed that moisture content was (85.5%), protein was (32.55%), lipid was (2.90%), ash was (7.20%), fibre was (4.80%), carbohydrate was (52.55%) and caloric value was (366.50%) respectively. This was found to be rich in protein and considerably high amount of carbohydrate. The anti-nutrient composition analysis revealed the presence of hydrocyanide (1.39mg/100g), Oxalate (114.40mg/100g), all of which are below toxic level except for oxalic acid. For mineral and vitamin compositions, potassium was significantly (P>0.05) higher than iron, sodium, calcium and phosphorus while vitamin A retinol was (371.72mg/100g) and vitamin C ascorbic acid (39.99mg/100g). Based on these findings the plant is recommended for consumption and for further investigation as a potential raw material for pharmaceutical industry.

  9. Continuous microcellular foaming of polylactic acid/natural fiber composites

    NASA Astrophysics Data System (ADS)

    Diaz-Acosta, Carlos A.

    Poly(lactic acid) (PLA), a biodegradable thermoplastic derived from renewable resources, stands out as a substitute to petroleum-based plastics. In spite of its excellent properties, commercial applications are limited because PLA is more expensive and more brittle than traditional petroleum-based resins. PLA can be blended with cellulosic fibers to reduce material cost. However, the lowered cost comes at the expense of flexibility and impact strength, which can be enhanced through the production of microcellular structures in the composite. Microcellular foaming uses inert gases (e.g., carbon dioxide) as physical blowing agents to make cellular structures with bubble sizes of less than 10 microm and cell-population densities (number of bubbles per unit volume) greater than 109 cells/cm³. These unique characteristics result in a significant increase in toughness and elongation at break (ductility) compared with unfoamed parts because the presence of small bubbles can blunt the crack-tips increasing the energy needed to propagate the crack. Microcellular foams have been produced through a two step batch process. First, large amounts of gas are dissolved in the solid plastic under high pressure (sorption process) to form a single-phase solution. Second, a thermodynamic instability (sudden drop in solubility) triggers cell nucleation and growth as the gas diffuses out of the plastic. Batch production of microcellular PLA has addressed some of the drawbacks of PLA. Unfortunately, the batch foaming process is not likely to be implemented in the industrial production of foams because it is not cost-effective. This study investigated the continuous microcellular foaming process of PLA and PLA/wood-fiber composites. The effects of the processing temperature and material compositions on the melt viscosity, pressure drop rate, and cell-population density were examined in order to understand the nucleation mechanisms in neat and filled PLA foams. The results indicated that

  10. Validation of lignocellulosic biomass carbohydrates determination via acid hydrolysis.

    PubMed

    Zhou, Shengfei; Runge, Troy M

    2014-11-01

    This work studied the two-step acid hydrolysis for determining carbohydrates in lignocellulosic biomass. Estimation of sugar loss based on acid hydrolyzed sugar standards or analysis of sugar derivatives was investigated. Four model substrates (starch, holocellulose, filter paper and cotton) and three levels of acid/material ratios (7.8, 10.3 and 15.4, v/w) were studied to demonstrate the range of test artifacts. The method for carbohydrates estimation based on acid hydrolyzed sugar standards having the most satisfactory carbohydrate recovery and relative standard deviation. Raw material and the acid/material ratio both had significant effect on carbohydrate hydrolysis, suggesting the acid to have impacts beyond a catalyst in the hydrolysis. Following optimal procedures, we were able to reach a carbohydrate recovery of 96% with a relative standard deviation less than 3%. The carbohydrates recovery lower than 100% was likely due to the incomplete hydrolysis of substrates, which was supported by scanning electron microscope (SEM) images.

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

    PubMed

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

    2008-08-01

    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.

  12. Membrane lipid composition of pancreatic AR42J cells: modification by exposure to different fatty acids.

    PubMed

    Audi, Nama'a; Mesa, María D; Martínez, María A; Martínez-Victoria, Emilio; Mañas, Mariano; Yago, María D

    2007-04-01

    Dietary fat type influences fatty acids in rat pancreatic membranes, in association with modulation of secretory activity and cell signalling in viable acini. We aimed to confirm whether AR42J cells are a valid model to study the interactions between lipids and pancreatic acinar cell function. For this purpose we have (i) compared the baseline fatty acid composition of AR42J cells with that of pancreatic membranes from rats fed a standard chow; (ii) investigated if fatty acids in AR42J membranes can be modified in culture; and (iii) studied if similar compositional variations that can be evoked in rats when dietary fat type is altered occur in AR42J cells. Weaning Wistar rats were fed for 8 weeks either a commercial chow (C) or semi-purified diets containing virgin olive oil (VOO) or sunflower oil (SO) as fat source. AR42J cells were incubated for 72 hrs in medium containing unmodified fetal calf serum (FCS, AR42J-C cells), FCS enriched with 18:1 n-9 (AR42J-O cells), or FCS enriched with 18:2 n-6 (AR42J-L cells). Fatty acids in crude membranes from rat pancreas and AR42J cells were determined by gas-liquid chromatography. Differences in membrane fatty acids between C rats and AR42J-C cells can be explained in part by variations in the amount of fatty acids in the extracellular environment. Supplementation of FCS with 18:1 n-9 or 18:2 n-6 changed the fatty acid spectrum of AR42J cells in a manner that resembles the pattern found, respectively, in VOO and SO rats, although AR42J-L cells were unable to accumulate 20:4 n-6. The AR42J cell line can be a useful tool to assess the effect of membrane compositional changes on acinar cell function. However, differences in baseline characteristics, and perhaps fatty acid metabolism, indicate that results obtained in AR42J cells should be confirmed with experiments in the whole animal.

  13. Various instrumental approaches for determination of organic acids in wines.

    PubMed

    Zeravik, Jiri; Fohlerova, Zdenka; Milovanovic, Miodrag; Kubesa, Ondrej; Zeisbergerova, Marta; Lacina, Karel; Petrovic, Aleksandar; Glatz, Zdenek; Skladal, Petr

    2016-03-01

    Biosensors based on lactate oxidase, sarcosine oxidase and mixture of fumarase and sarcosine oxidase were used for monitoring of organic acids in wine samples. Additionally, tartaric acid was determined by modified colorimetric method based on formation of the vanadate-tartrate complex. The above mentioned methods were used for the analysis of 31 wine samples and obtained data were compared with the results from capillary electrophoresis as a basic standard method. This comparison showed a certain degree of correlation between biosensors and capillary electrophoresis. The provided information pointed to the potential uses of biosensors in the field of winemaking.

  14. Determination and characterization of kernel biochemical composition and functional compounds of Persian walnut oil.

    PubMed

    Gharibzahedi, Seyed Mohammad Taghi; Mousavi, Seyed Mohammad; Hamedi, Manouchehr; Khodaiyan, Faramarz

    2014-01-01

    Kernel chemical composition and fatty acids profile of three walnut cultivars (Toyserkan, Chaboksar and Karaj) was analyzed. Some physicochemical properties, total phenolics content (TPC), ortho-diphenols content (ODC) and total tocopherol concentration (TTC) of extracted oils from the walnuts were also determined. The antioxidant activity of oil was measured by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity and β-carotene bleaching assays. The analysis of chemical composition revealed that protein and dietary fiber was highest in Toyserkan cultivar. Phosphorus was the most abundant element in the walnut kernels, followed by potassium, magnesium and calcium. The linoleic acid and linolenic contents ranged from 50.15% to 51.36% and 10.48% to 12.04%, respectively. Also, the results demonstrated that acid value, saponification value and viscosity of extracted oil had significantly varied between all cultivars. The extracted oil from Chaboksar cultivar illustrated more hydro peroxides and secondary products than those obtained from other cultivars. A positive correlation was found between Rancimat values and oleic acid content (r = 0.60), but considerably negative correlation with TTC (r = -0.81) and TPC (r = -0.92). The relationship between percentage of remaining DPPH radical and β-carotene of walnut oils showed high correlation among three selected cultivars (r = -0.94 to -0.97). PMID:24426045

  15. Intramuscular fat and fatty acid composition of longissimus muscle from divergent pure breeds of cattle.

    PubMed

    Dinh, T T N; Blanton, J R; Riley, D G; Chase, C C; Coleman, S W; Phillips, W A; Brooks, J C; Miller, M F; Thompson, L D

    2010-02-01

    The objective of this study was to compare the fatty acid (FA) composition of intramuscular fat from the LM of 3 divergent breeds of cattle: Angus (AN, n = 9), Brahman (BR, n = 7), and Romosinuano (RM, n = 11). Cattle were blocked by breed and finished 129 d before slaughter in one year and 157 d in the next year. Longissimus muscle samples were collected from each carcass between the 10th and 13th ribs, trimmed of external fat, frozen in liquid nitrogen, homogenized, and used for fat extraction, using a modified Folch procedure. Extracted fat was analyzed for FA by using a GLC system with an HP-88 capillary column. Fatty acid composition was expressed using both a normalized percentage (%) and gravimetric calculation (mg/g of fresh muscle tissue) in relation to degree of saturation, which was determined using a saturation index (ratio of total SFA to total unsaturated FA). Crude fat determination revealed that LM from AN purebred cattle had the greatest amount of intramuscular fat (7.08%; P = 0.001). Although intramuscular fat of LM from RM contained a reduced percentage of total SFA (P = 0.002) compared with AN, it had the greatest percentage of total PUFA (P < 0.001 and P = 0.020). The percentages of total MUFA were similar among the 3 breeds (P = 0.675). The gravimetric calculation, a measure of actual FA concentration, showed significantly greater concentrations of SFA (26.67 mg/g), MUFA (26.50 mg/g), and PUFA (2.37 mg/g) in LM from AN cattle, as compared with LM from BR and RM cattle (P < 0.001). Interestingly, BR purebreds had the least PUFA concentration (1.49 mg/g; P composition (1.49 to 2.37 mg/g and 4.36 to 8.78%; P < 0.001). Beef LM fatty acid composition was characterized by palmitic and oleic acids being the most

  16. Intramuscular fat and fatty acid composition of longissimus muscle from divergent pure breeds of cattle.

    PubMed

    Dinh, T T N; Blanton, J R; Riley, D G; Chase, C C; Coleman, S W; Phillips, W A; Brooks, J C; Miller, M F; Thompson, L D

    2010-02-01

    The objective of this study was to compare the fatty acid (FA) composition of intramuscular fat from the LM of 3 divergent breeds of cattle: Angus (AN, n = 9), Brahman (BR, n = 7), and Romosinuano (RM, n = 11). Cattle were blocked by breed and finished 129 d before slaughter in one year and 157 d in the next year. Longissimus muscle samples were collected from each carcass between the 10th and 13th ribs, trimmed of external fat, frozen in liquid nitrogen, homogenized, and used for fat extraction, using a modified Folch procedure. Extracted fat was analyzed for FA by using a GLC system with an HP-88 capillary column. Fatty acid composition was expressed using both a normalized percentage (%) and gravimetric calculation (mg/g of fresh muscle tissue) in relation to degree of saturation, which was determined using a saturation index (ratio of total SFA to total unsaturated FA). Crude fat determination revealed that LM from AN purebred cattle had the greatest amount of intramuscular fat (7.08%; P = 0.001). Although intramuscular fat of LM from RM contained a reduced percentage of total SFA (P = 0.002) compared with AN, it had the greatest percentage of total PUFA (P < 0.001 and P = 0.020). The percentages of total MUFA were similar among the 3 breeds (P = 0.675). The gravimetric calculation, a measure of actual FA concentration, showed significantly greater concentrations of SFA (26.67 mg/g), MUFA (26.50 mg/g), and PUFA (2.37 mg/g) in LM from AN cattle, as compared with LM from BR and RM cattle (P < 0.001). Interestingly, BR purebreds had the least PUFA concentration (1.49 mg/g; P composition (1.49 to 2.37 mg/g and 4.36 to 8.78%; P < 0.001). Beef LM fatty acid composition was characterized by palmitic and oleic acids being the most

  17. Conductometric simultaneous determination of acetic acid, monochloroacetic acid and trichloroacetic acid using orthogonal signal correction-partial least squares.

    PubMed

    Ghorbani, R; Ghasemi, J; Abdollahi, B

    2006-04-17

    A simultaneous conductometric titration method for determination of mixtures of acetic acid, monochloroacetic acid and trichloroacetic acid based on the multivariate calibration partial least squares is proposed. It is possible to obtain an adjustable model to relate squared concentration values of the mixtures used in the calibration range by conductance. The effect of orthogonal signal correction (OSC) as a preprocessing technique used to remove the information unrelated to the target variables is studied. The calibration model was build using conductometric titrations data of 16 mixtures of three acids. The concentration matrix was designed by a orthogonal design. The root mean squares error of prediction (RMSEP) for acetic acid, monochloroacetic acid and trichloroacetic acid with and without OSC were 0.08, 0.30 and 0.08, and 0.15, 0.40 and 0.18, respectively. The results obtained by OSC-PLS are better than the PLS and this indicate the successful application of the OSC filter as a good preprocessing method in multivariate calibration methods. The proposed procedure allows the simultaneous determination of these acids, in the synthetic mixtures.

  18. Characterization of lipid and fatty acids composition of Chlorella zofingiensis in response to nitrogen starvation.

    PubMed

    Zhu, Shunni; Wang, Yajie; Shang, Changhua; Wang, Zhongming; Xu, Jingliang; Yuan, Zhenhong

    2015-08-01

    Cellular biochemical composition of the microalga Chlorella zofingiensis was studied under favorable and nitrogen starvation conditions, with special emphasis on lipid classes and fatty acids distribution. When algal cells were grown in nitrogen-free medium (N stress), the increase in the contents of lipid and carbohydrate while a decrease in protein content was detected. Glycolipids were the major lipid fraction (50.7% of total lipids) under control condition, while neutral lipids increased to be predominant (86.7% of total lipids) under N stress condition. Triacylglycerol (TAG) content in N stressed cells was 27.3% dw, which was over three times higher than that obtained under control condition. Within neutral lipids fraction, monounsaturated fatty acids (MUFA) were the main group (40.6%) upon N stress, in which oleic acid was the most representative fatty acids (34.5%). Contrarily, glycolipids and phospholipids showed a higher percentage of polyunsaturated fatty acids (PUFA). Lipid quality assessment indicated the potential of this alga as a biodiesel feedstock when its neutral lipids were a principal lipid fraction. The results demonstrate that the neutral lipids content is key to determine the suitability of the microalga for biodiesel, and the stress cultivation is essential for lipid quality.

  19. Simple torsion test for shear moduli determination of orthotropic composites

    NASA Technical Reports Server (NTRS)

    Sumsion, H. T.; Rajapakse, Y. D. S.

    1978-01-01

    The shear moduli G13 and G23 for two different composites (AS/3501 and T300/5209) of uniaxial and cross-ply fiber orientations were determined by torsion testing of flat specimens of rectangular cross section. Torsion tests were run under controlled angle of twist in an electro-hydraulic servo-controlled test system. Both laser and potentiometer methods of measuring the angle of twist were used. The in-plane shear modulus was calculated with a formula for transversally isotropic materials and a formula for orthotropic materials, while the out-of-plane shear modulus was calculated from the orthotropic material formula. Neither the uniaxial nor the angle-ply composite materials studied were transversely isotropic. The degree of anisotropy for the angle-ply materials was several times greater than that of the uniaxial composites. For specimens of uniaxial fiber orientation, the in-plane shear moduli could be calculated to a good approximation by using the isotropic formula and test machine deflection data.

  20. Determination of urine ionic composition with potentiometric multisensor system.

    PubMed

    Yaroshenko, Irina; Kirsanov, Dmitry; Kartsova, Lyudmila; Sidorova, Alla; Borisova, Irina; Legin, Andrey

    2015-01-01

    The ionic composition of urine is a good indicator of patient's general condition and allows for diagnostics of certain medical problems such as e.g., urolithiasis. Due to environmental factors and malnutrition the number of registered urinary tract cases continuously increases. Most of the methods currently used for urine analysis are expensive, quite laborious and require skilled personnel. The present work deals with feasibility study of potentiometric multisensor system of 18 ion-selective and cross-sensitive sensors as an analytical tool for determination of urine ionic composition. In total 136 samples from patients of Urolithiasis Laboratory and healthy people were analyzed by the multisensor system as well as by capillary electrophoresis as a reference method. Various chemometric approaches were implemented to relate the data from electrochemical measurements with the reference data. Logistic regression (LR) was applied for classification of samples into healthy and unhealthy producing reasonable misclassification rates. Projection on Latent Structures (PLS) regression was applied for quantitative analysis of ionic composition from potentiometric data. Mean relative errors of simultaneous prediction of sodium, potassium, ammonium, calcium, magnesium, chloride, sulfate, phosphate, urate and creatinine from multisensor system response were in the range 3-13% for independent test sets. This shows a good promise for development of a fast and inexpensive alternative method for urine analysis. PMID:25281140

  1. Obesogenic diets enriched in oleic acid vs saturated fatty acids differentially modify polyunsaturated fatty acid composition in liver and visceral adipose

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Emerging evidence indicates that the fatty acid composition of obesogenic diets impacts physiologic outcomes. Much attention is focused on the biologic effects of consuming monounsaturated fatty acids (MUFA) vs saturated fatty acids (SFA). We investigated the extent to which an obesogenic diet high ...

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

    NASA Technical Reports Server (NTRS)

    Engel, M. H.; Nagy, B.

    1982-01-01

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

  3. Determination of domoic acid in shellfish extracted by molecularly imprinted polymers.

    PubMed

    Lin, Zhengzhong; Wang, Dan; Peng, Aihong; Huang, Zhiyong; Lin, Yuhui

    2016-08-01

    A selective sample cleanup method using molecularly imprinted polymers was developed for the separation of domoic acid (a shellfish toxin) from shellfish samples. The molecularly imprinted polymers for domoic acid was prepared by emulsion polymerization using 1,3,5-pentanetricarboxylic acid as the template molecule, 4-vinyl pyridine as the functional monomer, ethylene glycol dimethacrylate as the crosslinker, and Span80/Tween-80 (1:1 v/v) as the composite emulsifiers. The molecularly imprinted polymer showed high affinity to domoic acid with a dissociation constant of 13.5 μg/mL and apparent maximum adsorption capacity of 1249 μg/g. They were used as a selective sorbent for the detection of domoic acid from seafood samples coupled with high-performance liquid chromatography. The detection limit of 0.17 μg/g was lower than the maximum level permitted by several authorities. The mean recoveries of domoic acid from clam samples were 93.0-98.7%. It was demonstrated that the proposed method could be applied to the determination of domoic acid from shellfish samples. PMID:27311699

  4. Conjugated linoleic acid alters growth performance, tissue lipid deposition, and fatty acid composition of darkbarbel catfish (Pelteobagrus vachelli).

    PubMed

    Dong, Gui-Fang; Liu, Wen-Zuo; Wu, Lin-Zhou; Yu, Deng-Hang; Huang, Feng; Li, Peng-Cheng; Yang, Yan-Ou

    2015-02-01

    Fatty liver syndrome is a prevalent problem of farmed fish. Conjugated linoleic acid (CLA) has received increased attention recently as a fat-reducing fatty acid to control fat deposition in mammals. Therefore, the aim of the present study was to determine whether dietary CLA can reduce tissue lipid content of darkbarbel catfish (Pelteobagrus vachelli) and whether decreased lipid content is partially due to alterations in lipid metabolism enzyme activities and fatty acid profiles. A 76-day feeding trial was conducted to investigate the effect of dietary CLA on the growth, tissue lipid deposition, and fatty acid composition of darkbarbel catfish. Five diets containing 0 % (control), 0.5 % (CLA0.5), 1 % (CLA1), 2 % (CLA2), and 3 % (CLA3) CLA levels were evaluated. Results showed that fish fed with 2-3 % CLA diets showed a significantly lower specific growth rate and feed conversion efficiency than those fed with the control diet. Dietary CLA decreased the lipid contents in the liver and intraperitoneal fat with the CLA levels from 1 to 3 %. Fish fed with 2-3 % CLA diets showed significantly higher lipoprotein lipase and hepatic triacylglycerol lipase activities in liver than those of fish fed with the control, and fish fed with 1-3 % CLA diets had significantly higher pancreatic triacylglycerol lipase activities in liver than those of fish fed with the control. Dietary CLA was incorporated into liver, intraperitoneal fat, and muscle lipids, with higher percentages observed in liver compared with other tissues. Liver CLA deposition was at the expense of monounsaturated fatty acids (MUFA). In contrast, CLA deposition appeared to be primarily at the expense of MUFA and n-3 polyunsaturated fatty acids (PUFA) in the intraperitoneal fat, whereas in muscle it was at the expense of n-3 PUFA. Our results suggested that CLA at a 1 % dose can reduce liver lipid content without eliciting any negative effect on growth rate in darkbarbel catfish. This lipid-lowering effect could

  5. Determination of the combined isotopic composition of atmospheric methane

    NASA Astrophysics Data System (ADS)

    Butterworth, Anna Lucy

    Methane is an important global warming gas, present in the atmosphere at a concentration of 1.714 ppmv. Its concentration has more than doubled since the start of the industrial revolution and the increase is generally acknowledged to be due to human activities. The continued rise in concentration of methane is believed to be contributing to an increase in mean global temperature. Recently, the global budget of methane has been constrained by balancing the magnitude and isotopic signature of the sources and sinks with the measured tropospheric abundance and isotopic composition. The dual element stable isotopic composition (δ13C and /delta D) of methane may be used to characterise different sources of methane. Traditional methods of determining the δ13C value and the /delta D value of methane require large sample sizes. An alternative approach to investigating the stable isotopic composition of methane was to determine the combined ratio of 13CH4 and 12CH3D (mass 17) relative to 12CH4 (mass 16) and quote the results on a δ17M scale. A static-vacuum mass spectrometer has been developed specifically for the determination of the 17M/16M ratio of sub- nanomole quantities of methane with a δ17M precision of [/pm]0.2/ /perthous. An on-line sample preparation technique has also been developed to separate the methane from 10 ml of air and provide a pure, dry, ~300 picomole methane sample for isotope ratio determination. The overall δ17M precision of the analysis of the methane in air samples was [<][/pm]0.5/ /perthous. A number of sources of atmospheric methane have been investigated, demonstrating that sources may be distinguished from each other on the δ17M scale. The very small sample requirements for the instrument permitted a simple air sampling procedure to be employed, which was particularly useful for collecting air samples in remote locations. Air samples, containing methane emitted by termites, were collected from a tropical rainforest. The methane produced

  6. Formation of titanium phosphate composites during phosphoric acid decomposition of natural sphene

    SciTech Connect

    Maslova, Marina V.; Rusanova, Daniela Naydenov, Valeri; Antzutkin, Oleg N.; Gerasimova, Lidia G.

    2008-12-15

    Decomposition of mineral sphene, CaTiOSiO{sub 4}, by H{sub 3}PO{sub 4} is investigated in detail. During the dissolution process, simultaneous calcium leaching and formation of titanium phosphate (TiP) take place. The main product of decomposition is a solid titanium phosphate-silica composite. The XRD, solid-sate NMR, IR, TGA, SEM and BET data were used to identify and characterize the composite as a mixture of crystalline Ti(HPO{sub 4}){sub 2}.H{sub 2}O and silica. When 80% phosphoric acid is used the decomposition degree is higher than 98% and calcium is completely transferred into the liquid phase. Formation of Ti(HPO{sub 4}){sub 2}.H{sub 2}O proceeds via formation of meta-stable titanium phosphate phases, Ti(H{sub 2}PO{sub 4})(PO{sub 4}).2H{sub 2}O and Ti(H{sub 2}PO{sub 4})(PO{sub 4}). The sorption affinities of TiP composites were examined in relation to caesium and strontium ions. A decrease of H{sub 3}PO{sub 4} concentration leads to formation of composites with greater sorption properties. The maximum sorption capacity of TiP is observed when 60% H{sub 3}PO{sub 4} is used in sphene decomposition. The work demonstrates a valuable option within the Ti(HPO{sub 4}){sub 2}.H{sub 2}O-SiO{sub 2} composite synthesis scheme, to use phosphoric acid flows for isolation of CaHPO{sub 4}.2H{sub 2}O fertilizer. - Graphical abstract: A new synthesis scheme for preparation of composite titanium phosphate (TiP) ion-exchangers upon one-stage decomposition process of natural sphene with phosphoric acid is presented. Syntheses of {alpha}-TiP-silica composites proceed via formation of meta-stable titanium phosphate phases. The concentration of H{sub 3}PO{sub 4} determines the porosity of final products and their sorption affinities.

  7. Determination of VOC emission rates and compositions for offset printing.

    PubMed

    Wadden, R A; Scheff, P A; Franke, J E; Conroy, L M; Keil, C B

    1995-07-01

    The release rates of volatile organic compounds (VOC) as fugitive emissions from offset printing are difficult to quantify, and the compositions are usually not known. Tests were conducted at three offset printing shops that varied in size and by process. In each case, the building shell served as the test "enclosure," and air flow and concentration measurements were made at each air entry and exit point. Emission rates and VOC composition were determined during production for (1) a small shop containing three sheetfed presses and two spirit duplicators (36,700 sheets, 47,240 envelopes and letterheads), (2) a medium-size industrial in-house shop with two webfed and three sheetfed presses, and one spirit duplicator (315,130 total sheets), and (3) one print room of a large commercial concern containing three webfed, heatset operations (1.16 x 10(6) ft) served by catalytic air pollution control devices. Each test consisted of 12 one-hour periods over two days. Air samples were collected simultaneously during each period at 7-14 specified locations within each space. The samples were analyzed by gas chromatography (GC) for total VOC and for 13-19 individual organics. Samples of solvents used at each shop were also analyzed by GC. Average VOC emission rates were 4.7-6.1 kg/day for the small sheetfed printing shop, 0.4-0.9 kg/day for the industrial shop, and 79-82 kg/day for the commercial print room. Emission compositions were similar and included benzene, toluene, xylenes, ethylbenzene, and hexane. Comparison of the emission rates with mass balance estimates based on solvent usage and composition were quite consistent.(ABSTRACT TRUNCATED AT 250 WORDS)

  8. Fatty acid composition of membrane bilayers: importance of diet polyunsaturated fat balance.

    PubMed

    Abbott, Sarah K; Else, Paul L; Atkins, Taleitha A; Hulbert, A J

    2012-05-01

    In one of the most extensive analyses to date we show that the balance of diet n-3 and n-6 polyunsaturated fatty acids (PUFA) is the most important determinant of membrane composition in the rat under 'normal' conditions. Young adult male Sprague-Dawley rats were fed one of twelve moderate-fat diets (25% of total energy) for 8weeks. Diets differed only in fatty acid (FA) profiles, with saturate (SFA) content ranging 8-88% of total FAs, monounsaturate (MUFA) 6-65%, total PUFA 4-81%, n-6 PUFA 3-70% and n-3 PUFA 1-70%. Diet PUFA included only essential FAs 18:2n-6 and 18:3n-3. Balance between n-3 and n-6 PUFA is defined as the PUFA balance (n-3 PUFA as % of total PUFA) and ranged 1-86% in the diets. FA composition was measured for brain, heart, liver, skeletal muscle, erythrocytes and plasma phospholipids, as well as adipose tissue and plasma triglycerides. The conformer-regulator model was used (slope=1 indicates membrane composition completely conforming to diet). Extensive changes in diet SFA, MUFA and PUFA had minimal effect on membranes (average slopes 0.01, 0.07, 0.07 respectively), but considerable influence on adipose tissue and plasma triglycerides (average slopes 0.27, 0.53, 0.47 respectively). Diet balance between n-3 and n-6 PUFA had a biphasic influence on membrane composition. When n-3 PUFA<10% of total PUFA, membrane composition completely conformed to diet (average slope 0.95), while diet PUFA balance>10% had little influence (average slope 0.19). The modern human diet has an average PUFA balance ~10% and this will likely have significant health implications.

  9. Selection of acid compositions in well construction in difficult geological conditions

    NASA Astrophysics Data System (ADS)

    Mishchenko, M. V.; Kamartdinov, M. R.

    2016-03-01

    Within the scope of the current work we have presented an approach towards selecting and substantiation of acid composition in accordance with petrophysical characteristics of formations for acid treatment of bottom-hole formation zones. Article presents the results of lab tests of selected acid compositions, in conditions, which model thermobaric conditions of a payzone, combined with an evaluation of hydraulic permeability change, and this, in its turn, should allow us to evaluate the quality of impact of the acid composition recipe on the reservoir formation.

  10. Dissolution of cerium(IV)-lanthanide(III) oxides: comparative effect of chemical composition, temperature, and acidity.

    PubMed

    Horlait, D; Clavier, N; Szenknect, S; Dacheux, N; Dubois, V

    2012-03-19

    The dissolution of Ce(1-x)Ln(x)O(2-x/2) solid solutions was undertaken in various acid media in order to evaluate the effects of several physicochemical parameters such as chemical composition, temperature, and acidity on the reaction kinetics. The normalized dissolution rates (R(L,0)) were found to be strongly modified by the trivalent lanthanide incorporation rate, due to the presence of oxygen vacancies decreasing the samples cohesion. Conversely, the nature of the trivalent cation considered only weakly impacted the R(L,0) values. The dependence of the normalized dissolution rates on the temperature then appeared to be of the same order of magnitude than that of chemical composition. Moreover, it allowed determining the corresponding activation energy (E(A) ≈ 60-85 kJ·mol(-1)) which accounts for a dissolution driven by surface-controlled reactions. A similar conclusion was made regarding the acidity of the solution: the partial order related to (H(3)O(+)) reaching about 0.7. Finally, the prevailing effect of the incorporation of aliovalent cations in the fluorite-type CeO(2) matrix on the dissolution kinetics precluded the observation of slight effects such as those linked to the complexing agents or to the crystal structure of the samples.

  11. Dissolution of cerium(IV)-lanthanide(III) oxides: Comparative effect of chemical composition, temperature, and acidity

    SciTech Connect

    Horlait, D.; Clavier, N.; Szenknect, S.; Dacheux, N.; Dubois, V.

    2012-03-15

    The dissolution of Ce{sub 1-x}Ln{sub x}O{sub 2-x/2} solid solutions was undertaken in various acid media in order to evaluate the effects of several physicochemical parameters such as chemical composition, temperature, and acidity on the reaction kinetics. The normalized dissolution rates (R{sub L,0}) were found to be strongly modified by the trivalent lanthanide incorporation rate, due to the presence of oxygen vacancies decreasing the samples cohesion. Conversely, the nature of the trivalent cation considered only weakly impacted the R{sub L,0} values. The dependence of the normalized dissolution rates on the temperature then appeared to be of the same order of magnitude than that of chemical composition. Moreover, it allowed determining the corresponding activation energy (E{sub A} ≅ 60-85 kJ.mol{sup -1}) which accounts for a dissolution driven by surface-controlled reactions. A similar conclusion was made regarding the acidity of the solution: the partial order related to (H{sub 3}O{sup +}) reaching about 0.7. Finally, the prevailing effect of the incorporation of aliovalent cations in the fluorite-type CeO{sub 2} matrix on the dissolution kinetics precluded the observation of slight effects such as those linked to the complexing agents or to the crystal structure of the samples. (authors)

  12. Determining chemical composition of materials through micro-CT images.

    PubMed

    Jussiani, Eduardo Inocente; Dos Reis, Paulo José; Appoloni, Carlos Roberto

    2016-10-01

    X-ray microtomography is a 3D non-destructive method which, through digital images, enables a view of the internal structure of samples. Recently, researchers have been extensively performing various methods in the attempt to determine the chemical composition of materials. This paper brings further insight into this matter and proposes a new experimental method for determining the internal chemical composition of samples. Using a set of standard samples, calibration curves can be created that allow to relate the average gray scale of a sample obtained through microtomographic images to the value of ρZeff(m). In this model, ρZeff(m) is the parameter that chemically characterizes a material. The exponent m is obtained by the average value obtained with standard samples, which were titanium dioxide (TiO2), calcium chloride (CaCl2), calcium hydroxide (Ca(OH)2), and calcium nitrate (Ca(NO3)2). For the samples scanning process, a Bruker SkyScan 1172 microCT was used for testing rocks, nylon, graphite, calcium carbonate (CaCO3) and aluminum samples. The experimental results achieved by this method were consistent with the theoretical values. PMID:27451140

  13. Simple torsion test for shear moduli determination of orthotropic composites

    NASA Technical Reports Server (NTRS)

    Sumsion, H. T.; Rajapakse, Y. D. S.

    1978-01-01

    By means of torsion tests performed on test specimens of the same material having a minimum of two different cross sections (flat sheet of different widths), the effective in-plane (G13) and out-of-plane (G23) shear moduli were determined for two composite materials of uniaxial and angleply fiber orientations. Test specimens were 16 plies (nominal 2 mm) thick, 100 mm in length, and in widths of 6.3, 9.5, 12.5, and 15.8 mm. Torsion tests were run under controlled deflection (constant angle of twist) using an electrohydraulic servocontrolled test system. In-plane and out-of-plane shear moduli were calculated from an equation derived in the theory of elasticity which relates applied torque, the torsional angle of twist, the specimen width/thickness ratio, and the ratio of the two shear moduli G13/G23. Results demonstrate that torsional shear moduli, G23 as well as G13, can be determined by simple torsion tests of flat specimens of rectangular cross section. Neither the uniaxial nor angleply composite material were transversely isotropic.

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

    NASA Astrophysics Data System (ADS)

    Goodfriend, Glenn A.; Weidman, Christopher R.

    2001-06-01

    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 to be higher in the umbonal portion of the shells (laid down when the clams are young) but constant from a biological age of 10 to 20 y to more than 100 y. Corresponding changes are also seen in amino acid composition and concentration: with increasing biological age of the clam: total amino acid concentration increases substantially, the acidic amino acids Asp, glutamic acid, and alanine decrease in relative concentration (mole-percent) and more basic amino acids including tyrosine, phenylalanine, and lysine increase in relative concentration. These ontogenetic trends are generally retained in the fossil shells. These trends may reflect changing protein composition related to changes in growth rate. Clams grow considerably faster in their youth than when they are older, as indicated by changes in the annual growth increments. Production of more acidic proteins, which play a role in crystal growth, may be favored during the phase of faster growth, whereas more structural proteins, perhaps enhancing structural strength of the shell, may be favored during later growth. These ontogenetic differences in protein composition affect the observed rates of racemization of the protein pool. Some weak diagenetic trends in amino acid composition and abundance may be represented in the time series of shells. These results emphasize the importance of standardization of the location from which samples are taken from shells for dating by amino acid racemization analysis.

  15. Flow-injection chemiluminescence determination of chlorinated isocyanuric acids.

    PubMed

    Safavi, Afsaneh; Karimi, Mohammad Ali

    2003-02-01

    A rapid and sensitive flow-injection chemiluminescence method is described for the determination of dichloro- and trichloroisocyanuric acids based on the chemiluminescence produced during their reaction with luminol in alkaline medium. The effects of analytical and flow-injection variables on these chemiluminescence systems and determination of both oxidants are discussed. The optimized method yielded 3sigma detection limits of 8x10(-8) and 5x10(-8) mol L(-1) for the sodium dichloroisocyanurate and trichloroisocyanuric acid, respectively. The optimum conditions were found to be as follows: NaOH, 1x10(-1) mol L(-1); luminol, 5x10(-3) mol L(-1); KI, 2x10(-3) mol L(-1) and flow rate, 3.5 mL min(-1). PMID:12589508

  16. 31 CFR 359.14 - How are composite rates determined?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... composite interest rates.): Composite rate = {(Fixed rate ÷ 2) + Semiannual inflation rate + } × 2. 2 2 Example for I bonds issued May 2002-October 2002: Fixed rate = 2.00% Inflation rate = 0.28% Composite...

  17. Determination of perfluoroalkyl carboxylic, sulfonic, and phosphonic acids in food.

    PubMed

    Ullah, Shahid; Alsberg, Tomas; Vestergren, Robin; Berger, Urs

    2012-11-01

    A sensitive and accurate method was developed and validated for simultaneous analysis of perfluoroalkyl carboxylic acids, sulfonic acids, and phosphonic acids (PFPAs) at low picograms per gram concentrations in a variety of food matrices. The method employed extraction with acetonitrile/water and cleanup on a mixed-mode co-polymeric sorbent (C8 + quaternary amine) using solid-phase extraction. High-performance liquid chromatographic separation was achieved on a C18 column using a mobile phase gradient containing 5 mM 1-methyl piperidine for optimal chromatographic resolution of PFPAs. A quadrupole time-of-flight high-resolution mass spectrometer operating in negative ion mode was used as detector. Method detection limits were in the range of 0.002 to 0.02 ng g(-1) for all analytes. Sample preparation (extraction and cleanup) recoveries at a spiking level of 0.1 ng g(-1) to a baby food composite were in the range of 59 to 98 %. A strong matrix effect was observed in the analysis of PFPAs in food extracts, which was tentatively assigned to sorption of PFPAs to the injection vial in the solvent-based calibration standard. The method was successfully applied to a range of different food matrices including duplicate diet samples, vegetables, meat, and fish samples.

  18. Direct comparison of fatty acid ratios in single cellular lipid droplets as determined by comparative Raman spectroscopy and gas chromatography.

    PubMed

    Schie, Iwan W; Nolte, Lena; Pedersen, Theresa L; Smith, Zach; Wu, Jian; Yahiatène, Idir; Newman, John W; Huser, Thomas

    2013-11-01

    Cellular lipid droplets are the least studied and least understood cellular organelles in eukaryotic and prokaryotic cells. Despite a significant body of research studying the physiology of lipid droplets it has not yet been possible to fully determine the composition of individual cellular lipid droplets. In this paper we use Raman spectroscopy on single cellular lipid droplets and least-squares fitting of pure fatty acid spectra to determine the composition of individual lipid droplets in cells after treatment with different ratios of oleic and palmitic acid. We validate the results of the Raman spectroscopy-based single lipid droplet analysis with results obtained by gas chromatography analysis of millions of cells, and find that our approach can accurately predict the relative amount of a specific fatty acid in the lipid droplet. Based on these results we show that the fatty acid composition in individual lipid droplets is on average similar to that of all lipid droplets found in the sample. Furthermore, we expand this approach to the investigation of the lipid composition in single cellular peroxisomes. We determine the location of cellular peroxisomes based on two-photon excitation fluorescence (TPEF) imaging of peroxisomes labeled with the green fluorescent protein, and successive Raman spectroscopy of peroxisomes. We find that in some cases peroxisomes can produce a detectable CARS signal, and that the peroxisomal Raman spectra exhibit an oleic acid-like signature.

  19. The bile acid composition of crane gallbladder bile

    USGS Publications Warehouse

    Serafin, J.A.

    1983-01-01

    1. 1. The biliary bile acids of the whooping crane (Grus americana) and the Florida sandhill crane (G. canadensis pratensis) have been examined. 2. 2. Cholic acid (CA), chenodeoxycholic acid (CDOCA) and lithocholic acid were found in bile from both species of these North American cranes. 3. 3. CDOCA and CA were the primary bile acids in both species, together constituting 70% or more of the bile acids by weight. 4. 4. The primary bile acids of cranes appear to be the same as those that have been identified in other avian species.

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

    DOEpatents

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

    1985-07-18

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

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

    DOEpatents

    Ostenak, Carl A.; Mackay, Harold A.

    1987-01-01

    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.

  2. GLC analysis of Indian rapeseed-mustard to study the variability of fatty acid composition.

    PubMed

    Kaushik, N; Agnihotri, A

    2000-12-01

    Rapeseed-mustard is one of the most economically important oilseed crops in India. Speciality oils having high amounts of a specific fatty acid are of immense importance for both nutritional and industrial purposes. Oil high in oleic acid has demand in commercial food-service applications due to a long shelf-life and cholesterol-reducing properties. Both linoleic and linolenic acids are essential fatty acids; however, less than 3% linolenic acid is preferred for oil stability. High erucic acid content is beneficial for the polymer industry, whereas low erucic acid is recommended for food purposes. Therefore, it is important to undertake systematic characterization of the available gene pool for its variable fatty acid profile to be utilized for specific purposes. In the present study the Indian rapeseed-mustard germplasm and some newly developed low-erucic-acid strains were analysed by GLC to study the fatty acid composition in these lines. The GLC analysis revealed that the rapeseed-mustard varieties being commonly grown in India are characterized by high erucic acid content (30-51%) in the oil with low levels of oleic acid (13-23%). However, from among the recently developed low-erucic-acid strains, several lines were identified with comparatively high oleic acid (60-70%), moderate to high linoleic acid (13-40%) and low linolenic acid (< 10%) contents. Work is in progress at TERI (New Delhi, India) to utilize these lines for development of strains with particular fatty acid compositions for specific purposes.

  3. Lipid content and fatty acid composition in foods commonly consumed by nursing Congolese women: incidences on their essential fatty acid intakes and breast milk fatty acids.

    PubMed

    Rocquelin, G; Tapsoba, S; Mbemba, F; Gallon, G; Picq, C

    1998-09-01

    The fat content and fatty acid (FA) composition of nearly 40 foods, currently consumed by 102 nursing Congolese mothers living in Brazzaville, were determined to assess their impact on mothers' essential fatty acid (EFA) intakes and breast milk FA. Data on mothers' milk FA and dietary habits which allowed food selection were recently published (Rocquelin et al., 1998). Most foods were locally produced. Food samples were collected at local markets, bleached if necessary to avoid microbial degradation, and stored at +4 degrees C or -20 degrees C. They were lyophilized upon their arrival in the laboratory before lipid analyses. FA composition of food lipids was determined by capillary gas chromatography. Staple diets included low-fat, high-carbohydrate foods (processed cassava roots, wheat bread) and high-polyunsaturated fatty acid (PUFA) foods: soybean oil (high in 18 : 2 n-6 and alpha-18 : 3 n-3), bushbutter (dacryodes edulis), peanuts, avocado (high in fat and 18 : 2 n-6), freshwater and salt-water fish (high in LC n-3 and/or n-6 PUFA), and leafy green vegetables (low in fat but very high in alpha-18 : 3 n-3). Their frequent consumption by nursing mothers provided enough EFA to meet requirements due to lactation. It also explains why mothers' breast milk was rich in C8-C14 saturated FA (26% of total FA) and in n-6, n-3 PUFA (respectively 15.0% and 2.4% of total FA) highly profitable for breastfed infants' development. From this point of view, dietary habits of Congolese mothers have to be sustained for they are more adequate than most Western-type diets.

  4. Neutrophil fatty acid composition: effect of a single session of exercise and glutamine supplementation.

    PubMed

    Lagranha, C J; Alba-Loureiro, T C; Martins, E F; Pithon-Curi, T C; Curi, R

    2008-06-01

    The fatty acid composition of immune cells appears to contribute to variations of cell function. The independent and combined effects of a single session of exercise (SSE) and glutamine supplementation (GS) on neutrophil fatty acid composition were investigated. Compared to control (no treatment given--i.e. neither SSE or GS), single session of exercise decreased myristic, palmitic and eicosapentaenoic (EPA) acids, and increased lauric, oleic, linoleic, arachidonic (AA) and docosahexaenoic (DHA) acids whereas glutamine supplementation combined with SSE (GS+SSE) increased oleic acid. Polyunsaturated/saturated fatty acid ratio and Unsaturation index were higher in neutrophils from the SSE and GS groups as compared with control. These findings support the proposition that SSE and GS may modulate neutrophil function through alterations in fatty acid composition. PMID:17721676

  5. [The preparation procedure of tests for the gas chromatographic determination of fat acids without preliminary extraction of lipids].

    PubMed

    Aripovskiĭ, A V; Kolesnik, P O; Vezhdel, M I; Titov, V N

    2012-01-01

    The enhancement of the procedure of quantitative gas chromatographic determination of fit acids in biologic liquids samples is proposed. Instead of the conventional Folch procedure of extraction of lipids with subsequent ablution, concentration and methylation of extracts the direct saponification and methylation of vacuum dried liquid samples (50-200 mkl) can be applied. To compare the effectiveness of the proposed and conventional procedures both of them had been applied to evaluate how converge the results of determination of composition of fat acids in whole blood, blood plasma, packed red blood cells, homogenates of hepatic and muscular tissues. The proposed procedure is applied to determine the characteristics of fat acids composition inpatients with ischemic heart disease.

  6. 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...

  7. Effect of trans-10 cis-12 conjugated linoleic acid on bovine oocyte competence and fatty acid composition.

    PubMed

    Lapa, M; Marques, C C; Alves, S P; Vasques, M I; Baptista, M C; Carvalhais, I; Silva Pereira, M; Horta, A E M; Bessa, R J B; Pereira, R M

    2011-10-01

    The reproductive performance of dairy cows may be improved by feeding conjugated linoleic acid (CLA) supplements during early lactation. The mechanism of action of t10,c12 CLA is not clearly known. Our objective was to investigate the effect of t10,c12 CLA on oocyte maturation and lipid composition of cumulus oocyte complexes (COC). The developmental potential of oocytes incubated in in vitro maturation (IVM) medium supplemented with t10,c12 CLA to the blastocyst stage and embryo quality were also assessed. In experiment 1, abattoir-derived oocytes were matured in TCM199 + 10% serum supplemented with 100 μM t10,c12 CLA (t10,c12 CLA n = 672) or without it (control n = 672). Mature oocytes were either stained for chromatin configuration or inseminated and cultured for embryo development assessment. In experiment 2, COC and IVM culture media were subjected to fatty acid (FA) analysis prior and after maturation with t10,c12 CLA or without it (control). Total lipids and FA profiles in oocytes, cumulus cells and culture media were determined by gas chromatography. t10,c12 CLA supplementation to IVM medium improved (p = 0.05) embryo quality evaluated morphologically. This effect was associated with t10,c12 CLA presence (3.1 ± 0.7%, p = 0.04) and lower levels of arachidonic acid in FA profile of t10,c12 CLA mature oocytes (immature oocytes = 4.4 ± 1.9%, t10,c12 CLA mature oocytes = 1.0 ± 0.7%, p = 0.05). Differences in myristic and eicotrienoic acids, saturated and unsaturated FA concentrations between oocytes and cumulus cells were detected (p ≤ 0.05). In conclusion, the presence of t10,c12 CLA during maturation interfered on lipid metabolism improving bovine oocyte competence to develop into higher quality embryos.

  8. Preparation and characterization of acorn starch/poly(lactic acid) composites modified with functionalized vegetable oil derivates.

    PubMed

    Li, Shouhai; Xia, Jianling; Xu, Yuzhi; Yang, Xuejuan; Mao, Wei; Huang, Kun

    2016-05-20

    Composites of acorn starch (AS) and poly(1actic acid) (PLA) modified with dimer fatty acid (DFA) or dimer fatty acid polyamide (DFAPA) were produced by a hot-melt extrusion method. The effects of DFA and DFAPA contents on the mechanical, hydrophobic, thermal properties and melt fluidity of the composites were studied under an invariable AS-to-PLA mass ratio of 40/60. SEM and DMA research results show that the compatibility of AS/PLA composites are determined by the dosage of DFA or DFAPA. The hydrophobicity and melt fluidity of composites are improved with the addition of DFA and DFAPA. The glass transition temperatures of the composites are all reduced remarkably by additives DFA and DFAPA. However, DFA and DFAPA exert different effects on the mechanical properties of AS/PLA composites. In the DFAPA-modified system, the tensile and flexural strength first increase and then decrease with the increase of DFAPA dosage; the mechanical strength is maximized when the dosage of DFAPA is 2 wt% of total weight. In the DFA-modified system, the tensile and flexural strength decrease with the increase of DFA dosage.

  9. Comparative Analysis of Lipid Content and Fatty Acid Composition of Commercially Important Fish and Shellfish from Sri Lanka and Japan.

    PubMed

    Devadason, Chandravathany; Jayasinghe, Chamila; Sivakanesan, Ramiah; Senarath, Samanthika; Beppu, Fumiaki; Gotoh, Naohiro

    2016-01-01

    Sri Lanka is surrounded by the Indian Ocean, allowing plenty of fishes to be caught. Moreover, these fishes represent one of the undocumented fish resources in the world and their detailed lipid profiles have not been previously examined. In this study, the lipid content and fatty acid composition of 50 commercially important fishes from the Indian Ocean (Sri Lanka) and the Pacific Ocean (Japan) were compared. The total lipid content and fatty acid composition, including eicosapentaenoic acid (C20:5n-3, EPA) and docosahexaenoic acid (C22:6n-3, DHA), differed significantly among species. Fish from the Pacific Ocean had higher proportions of fatty acids, including EPA and DHA. Herrings and mackerels from both oceanic areas demonstrated high levels of EPA and DHA, and n-3/n-6 ratio. Brackish and freshwater fishes from both groups showed low levels of PUFAs. Fish from the Indian Ocean were high in n-6 fatty acids. Monounsaturated fatty acid levels were high in omnivorous fish from the Pacific Ocean, and saturated fatty acid levels were high in fish from the Indian Ocean. The results of this study will be of value in determining the dietary usefulness of fish caught in Sri Lanka. PMID:27373421

  10. Fatty acid composition, including CLA's isomers and cholesterol content of m. longissimus lumborum and m. semimebranosus of Katahdin, Suffolk, Katahdin x Suffolk, and Suffolk x Katahdin lambs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lipids in meat products have important human health implications. Muscle tissues from Katahdin (KK), Suffolk (SS), Katahdin x Suffolk (KS), and Suffolk x Katahdin (SS) lambs were analyzed to determine the effect of breed-type on muscle fatty acid composition, including conjugated linoleic acid (CLA)...

  11. Hexuronic acid stereochemistry determination in chondroitin sulfate glycosaminoglycan oligosaccharides by electron detachment dissociation.

    PubMed

    Leach, Franklin E; Ly, Mellisa; Laremore, Tatiana N; Wolff, Jeremy J; Perlow, Jacob; Linhardt, Robert J; Amster, I Jonathan

    2012-09-01

    Electron detachment dissociation (EDD) has previously provided stereo-specific product ions that allow for the assignment of the acidic C-5stereochemistry in heparan sulfate glycosaminoglycans (GAGs), but application of the same methodology to an epimer pair in the chondroitin sulfate glycoform class does not provide the same result. A series of experiments have been conducted in which glycosaminoglycan precursor ions are independently activated by electron detachment dissociation (EDD), electron induced dissociation (EID), and negative electron transfer dissociation (NETD) to assign the stereochemistry in chondroitin sulfate (CS) epimers and investigate the mechanisms for product ion formation during EDD in CS glycoforms. This approach allows for the assignment of electronic excitation products formed by EID and detachment products to radical pathways in NETD, both of which occur simultaneously during EDD. The uronic acid stereochemistry in electron detachment spectra produces intensity differences when assigned glycosidic and cross-ring cleavages are compared. The variations in the intensities of the doubly deprotonated (0,2)X(3) and Y(3) ions have been shown to be indicative of CS-A/DS composition during the CID of binary mixtures. These ions can provide insight into the uronic acid composition of binary mixtures in EDD, but the relative abundances, although reproducible, are low compared with those in a CID spectrum acquired on an ion trap. The application of principal component analysis (PCA) presents a multivariate approach to determining the uronic acid stereochemistry spectra of these GAGs by taking advantage of the reproducible peak distributions produced by electron detachment.

  12. Hexuronic Acid Stereochemistry Determination in Chondroitin Sulfate Glycosaminoglycan Oligosaccharides by Electron Detachment Dissociation

    NASA Astrophysics Data System (ADS)

    Leach, Franklin E.; Ly, Mellisa; Laremore, Tatiana N.; Wolff, Jeremy J.; Perlow, Jacob; Linhardt, Robert J.; Amster, I. Jonathan

    2012-09-01

    Electron detachment dissociation (EDD) has previously provided stereo-specific product ions that allow for the assignment of the acidic C-5stereochemistry in heparan sulfate glycosaminoglycans (GAGs), but application of the same methodology to an epimer pair in the chondroitin sulfate glycoform class does not provide the same result. A series of experiments have been conducted in which glycosaminoglycan precursor ions are independently activated by electron detachment dissociation (EDD), electron induced dissociation (EID), and negative electron transfer dissociation (NETD) to assign the stereochemistry in chondroitin sulfate (CS) epimers and investigate the mechanisms for product ion formation during EDD in CS glycoforms. This approach allows for the assignment of electronic excitation products formed by EID and detachment products to radical pathways in NETD, both of which occur simultaneously during EDD. The uronic acid stereochemistry in electron detachment spectra produces intensity differences when assigned glycosidic and cross-ring cleavages are compared. The variations in the intensities of the doubly deprotonated 0,2X3 and Y3 ions have been shown to be indicative of CS-A/DS composition during the CID of binary mixtures. These ions can provide insight into the uronic acid composition of binary mixtures in EDD, but the relative abundances, although reproducible, are low compared with those in a CID spectrum acquired on an ion trap. The application of principal component analysis (PCA) presents a multivariate approach to determining the uronic acid stereochemistry spectra of these GAGs by taking advantage of the reproducible peak distributions produced by electron detachment.

  13. Method for determination of fatty acids in bovine colostrum using GC-FID.

    PubMed

    Yurchenko, S; Sats, A; Poikalainen, V; Karus, A

    2016-12-01

    Bovine colostrum is potentially valuable source of essential fatty acids (FAs), but so far only few studies have made the effort to estimate FA composition of this potential resource. The aim of current research was to fill this gap with selecting and validating an accurate procedure for the analysis of the composition of the FAs in bovine colostrum. We used colostrum samples of Holstein-Friesian cattle from Märja experimental farm as a test material. The validated method includes derivatization, in which FAs are sent through esterification with the acidic catalyst boron trifluoride. Formed methyl esters of fatty acids (FAMEs) were analysed using GC-FID. The obtained LOD and the LOQ of FAMEs were 0.11-0.68 and 0.37-2.27ppm, respectively. The analysis of fortified samples showed very good and similar recoveries, indicating that the method proposed here can be routinely used for determination and investigation of the fatty acids in dairy products. PMID:27374514

  14. Composition of amino acids in feed ingredients for animal diets.

    PubMed

    Li, Xilong; Rezaei, Reza; Li, Peng; Wu, Guoyao

    2011-04-01

    Dietary amino acids (AA) are crucial for animal growth, development, reproduction, lactation, and health. However, there is a scarcity of information regarding complete composition of "nutritionally nonessential AA" (NEAA; those AA which can be synthesized by animals) in diets. To provide a much-needed database, we quantified NEAA (including glutamate, glutamine, aspartate, and asparagine) in feed ingredients for comparison with "nutritionally essential AA" (EAA; those AA whose carbon skeletons cannot be formed by animals). Except for gelatin and feather meal, animal and plant ingredients contained high percentages of glutamate plus glutamine, branched-chain AA, and aspartate plus asparagine, which were 10-32, 15-25, and 8-14% of total protein, respectively. In particular, leucine and glutamine were most abundant in blood meal and casein (13% of total protein), respectively. Notably, gelatin, feather meal, fish meal, meat and bone meal, and poultry byproduct had high percentages of glycine, proline plus hydroxyproline, and arginine, which were 10-35, 9.6-35, and 7.2-7.9% of total protein, respectively. Among plant products, arginine was most abundant in peanut meal and cottonseed meal (14-16% of total protein), whereas corn and sorghum had low percentages of cysteine, lysine, methionine, and tryptophan (0.9-3% of total protein). Overall, feed ingredients of animal origin (except for gelatin) are excellent sources of NEAA and EAA for livestock, avian, and aquatic species, whereas gelatin provides highest amounts of arginine, glycine, and proline plus hydroxyproline. Because casein, corn, soybean, peanut, fish, and gelatin are consumed by children and adults, our findings also have important implications for human nutrition.

  15. Determining the polysaccharide composition of plant cell walls.

    PubMed

    Pettolino, Filomena A; Walsh, Cherie; Fincher, Geoffrey B; Bacic, Antony

    2012-09-01

    The plant cell wall is a chemically complex structure composed mostly of polysaccharides. Detailed analyses of these cell wall polysaccharides are essential for our understanding of plant development and for our use of plant biomass (largely wall material) in the food, agriculture, fabric, timber, biofuel and biocomposite industries. We present analytical techniques not only to define the fine chemical structures of individual cell wall polysaccharides but also to estimate the overall polysaccharide composition of cell wall preparations. The procedure covers the preparation of cell walls, together with gas chromatography-mass spectrometry (GC-MS)-based methods, for both the analysis of monosaccharides as their volatile alditol acetate derivatives and for methylation analysis to determine linkage positions between monosaccharide residues as their volatile partially methylated alditol acetate derivatives. Analysis time will vary depending on both the method used and the tissue type, and ranges from 2 d for a simple neutral sugar composition to 2 weeks for a carboxyl reduction/methylation linkage analysis. PMID:22864200

  16. Determining the polysaccharide composition of plant cell walls.

    PubMed

    Pettolino, Filomena A; Walsh, Cherie; Fincher, Geoffrey B; Bacic, Antony

    2012-09-01

    The plant cell wall is a chemically complex structure composed mostly of polysaccharides. Detailed analyses of these cell wall polysaccharides are essential for our understanding of plant development and for our use of plant biomass (largely wall material) in the food, agriculture, fabric, timber, biofuel and biocomposite industries. We present analytical techniques not only to define the fine chemical structures of individual cell wall polysaccharides but also to estimate the overall polysaccharide composition of cell wall preparations. The procedure covers the preparation of cell walls, together with gas chromatography-mass spectrometry (GC-MS)-based methods, for both the analysis of monosaccharides as their volatile alditol acetate derivatives and for methylation analysis to determine linkage positions between monosaccharide residues as their volatile partially methylated alditol acetate derivatives. Analysis time will vary depending on both the method used and the tissue type, and ranges from 2 d for a simple neutral sugar composition to 2 weeks for a carboxyl reduction/methylation linkage analysis.

  17. Genome-wide association and prediction of direct genomic breeding values for composition of fatty acids in Angus beef cattlea

    PubMed Central

    2013-01-01

    Background As consumers continue to request food products that have health advantages, it will be important for the livestock industry to supply a product that meet these demands. One such nutrient is fatty acids, which have been implicated as playing a role in cardiovascular disease. Therefore, the objective of this study was to determine the extent to which molecular markers could account for variation in fatty acid composition of skeletal muscle and identify genomic regions that harbor genetic variation. Results Subsets of markers on the Illumina 54K bovine SNPchip were able to account for up to 57% of the variance observed in fatty acid composition. In addition, these markers could be used to calculate a direct genomic breeding values (DGV) for a given fatty acids with an accuracy (measured as simple correlations between DGV and phenotype) ranging from -0.06 to 0.57. Furthermore, 57 1-Mb regions were identified that were associated with at least one fatty acid with a posterior probability of inclusion greater than 0.90. 1-Mb regions on BTA19, BTA26 and BTA29, which harbored fatty acid synthase, Sterol-CoA desaturase and thyroid hormone responsive candidate genes, respectively, explained a high percentage of genetic variance in more than one fatty acid. It was also observed that the correlation between DGV for different fatty acids at a given 1-Mb window ranged from almost 1 to -1. Conclusions Further investigations are needed to identify the causal variants harbored within the identified 1-Mb windows. For the first time, Angus breeders have a tool whereby they could select for altered fatty acid composition. Furthermore, these reported results could improve our understanding of the biology of fatty acid metabolism and deposition. PMID:24156620

  18. Fatty Acid Composition of Egg Yolk from Chickens Fed a Diet including Marigold (Tagetes erecta L.)

    PubMed Central

    Altuntaş, A.; Aydin, R.

    2014-01-01

    The objective of this study was to determine the effects of diet supplemented with marigold on egg yolk fatty acid composition and egg quality parameters. Sixty hens were assigned into three groups and fed diets supplemented with 0 (control), 10 g kg−1, or 20 g kg−1 marigold for 42 days. Eggs collected at the 6th week of the study were analyzed for fatty acid analysis. Laying performance, egg quality parameters, and feed intake were also evaluated. Yolk color scores in the group fed the 20 g kg−1 marigold-supplemented diet were found greater than control (10.77 versus 9.77). Inclusion of 20 g kg−1 marigold in diet influenced egg weights adversely compared to the control. Diet supplemented with 10 g kg−1 or 20 g kg−1 marigold increased the levels of C16:0 and C18:0 and decreased levels of C16:1 (n-7) and C18:1 (n-9) in the egg yolk. Also, diet including marigold increased total saturated fatty acids (SFA) and decreased monounsaturated fatty acids (MUFA) in the egg yolk. PMID:25587451

  19. Fatty Acid Composition of Egg Yolk from Chickens Fed a Diet including Marigold (Tagetes erecta L.).

    PubMed

    Altuntaş, A; Aydin, R

    2014-01-01

    The objective of this study was to determine the effects of diet supplemented with marigold on egg yolk fatty acid composition and egg quality parameters. Sixty hens were assigned into three groups and fed diets supplemented with 0 (control), 10 g kg(-1), or 20 g kg(-1) marigold for 42 days. Eggs collected at the 6th week of the study were analyzed for fatty acid analysis. Laying performance, egg quality parameters, and feed intake were also evaluated. Yolk color scores in the group fed the 20 g kg(-1) marigold-supplemented diet were found greater than control (10.77 versus 9.77). Inclusion of 20 g kg(-1) marigold in diet influenced egg weights adversely compared to the control. Diet supplemented with 10 g kg(-1) or 20 g kg(-1) marigold increased the levels of C16:0 and C18:0 and decreased levels of C16:1 (n-7) and C18:1 (n-9) in the egg yolk. Also, diet including marigold increased total saturated fatty acids (SFA) and decreased monounsaturated fatty acids (MUFA) in the egg yolk. PMID:25587451

  20. Simultaneous determination of salicylic acid and salicylamide in biological fluids

    NASA Astrophysics Data System (ADS)

    Murillo Pulgarín, J. A.; Alañón Molina, A.; Sánchez-Ferrer Robles, I.

    2011-09-01

    A new methodology for the simultaneous determination of salicylic acid and salicylamide in biological fluids is proposed. The strong overlapping of the fluorescence spectra of both analytes makes impossible the conventional fluorimetric determination. For that reason, the use of fluorescence decay curves to resolve mixtures of analytes is proposed; this is a novel technique that provides the benefits in selectivity and sensitivity of the fluorescence decay curves. In order to assess the goodness of the proposed method, a prediction set of synthetic samples were analyzed obtaining recuperation percentages between 98.2 and 104.6%. Finally, a study of the detection limits was done using a new criterion resulting in values for the detection limits of 8.2 and 11.6 μg L -1 for salicylic acid and salicylamide respectively. The validity of the method was tested in human serum and human urine spiked with aliquots of the analytes. Recoveries obtained were 96.2 and 94.5% for salicylic acid and salicylamide respectively.

  1. Nanostructured Composites: Effective Mechanical Property Determination of Nanotube Bundles

    NASA Technical Reports Server (NTRS)

    Saether, E.; Pipes, R. B.; Frankland, S. J. V.

    2002-01-01

    Carbon nanotubes naturally tend to form crystals in the form of hexagonally packed bundles or ropes that should exhibit a transversely isotropic constitutive behavior. Although the intratube axial stiffness is on the order of 1 TPa due to a strong network of delocalized bonds, the intertube cohesive strength is orders of magnitude less controlled by weak, nonbonding van der Waals interactions. An accurate determination of the effective mechanical properties of nanotube bundles is important to assess potential structural applications such as reinforcement in future composite material systems. A direct method for calculating effective material constants is developed in the present study. The Lennard-Jones potential is used to model the nonbonding cohesive forces. A complete set of transverse moduli are obtained and compared with existing data.

  2. Effect of feeding intensity and time on feed on intramuscular fatty acid composition of Simmental bulls.

    PubMed

    Sami, A S; Augustini, C; Schwarz, F J

    2004-06-01

    Seventy-two Simmental bulls, weighing 489 kg initially and approximately 15 months old, were divided into four groups to determine the effects of feeding intensity and time on feed on intramuscular fatty acid (FA) composition. Two groups of 18 bulls each were extensively (E) or intensively (I) fed on maize silage and concentrates with a daily gain of 943 g (E) or 1371 g (I). Half of each group were slaughtered after 100 days (S) or 138 days (L) on feed. In addition to carcass fatness parameters, intramuscular FA composition was also measured. Only small differences in the sum of saturated FA (SFA) percentages were found with 47.7 and 47.5% FA methyl esters (FAME) for SE and LE, respectively, and 48.7% FAME for each of SI and LI. Monounsaturated fatty acids (MUFA) significantly increased with longer, and higher feeding intensity to 44.2% FAME (LI), whereas the other groups had similar contents of 41.9, 42.2 and 42.0% FAME (SE, LE and SI respectively). Polyunsaturated FA (PUFA) decreased with higher feeding intensity to 8.39% (SI) and 6.71% (LI) FAME (p < 0.05) in comparison with 9.48% (SE) and 9.54% (LE). Intensive feeding decreased the ratio of PUFA : SFA to 0.17 (SI) and 0.14 (LI, p < 0.05) in comparison with 0.20 (SE and LE). The mean conjugated linoleic acid (CLA) concentration was 0.41% FAME. Time on feed had only a small effect on the FA composition compared with feeding intensity. No significant relationships were detected between meat quality attributes and the pattern of FA. PMID:15189422

  3. Cellular fatty acid composition of Actinobacillus actinomycetemcomitans and Haemophilus aphrophilus.

    PubMed

    Braunthal, S D; Holt, S C; Tanner, A C; Socransky, S S

    1980-06-01

    Strains of Actinobacillus actinomycetemcomitans isolated from deep pockets of patients with juvenile periodontitis were analyzed for their content of cellular fatty acids. Oral Haemophilus strains, morphologically and biochemically similar to Haemophilus aphrophilus, were also examined for their content of cellular fatty acids. The extractable lipids of the actinobacilli represented approximately 10% of the cell dry weight, with the bound lipids representing 2 to 5%. The major fatty acids consisted of myristic (C14:0) and palmitic (C16:0) acids and a C16:1 acid, possibly palmitoleic acid, accounting for 21, 35, and 31% of the total extractable fatty acids, respectively. Haemophilus strains had a similar cellular fatty acid content. PMID:7430333

  4. Cellular fatty acid composition of Actinobacillus actinomycetemcomitans and Haemophilus aphrophilus.

    PubMed Central

    Braunthal, S D; Holt, S C; Tanner, A C; Socransky, S S

    1980-01-01

    Strains of Actinobacillus actinomycetemcomitans isolated from deep pockets of patients with juvenile periodontitis were analyzed for their content of cellular fatty acids. Oral Haemophilus strains, morphologically and biochemically similar to Haemophilus aphrophilus, were also examined for their content of cellular fatty acids. The extractable lipids of the actinobacilli represented approximately 10% of the cell dry weight, with the bound lipids representing 2 to 5%. The major fatty acids consisted of myristic (C14:0) and palmitic (C16:0) acids and a C16:1 acid, possibly palmitoleic acid, accounting for 21, 35, and 31% of the total extractable fatty acids, respectively. Haemophilus strains had a similar cellular fatty acid content. PMID:7430333

  5. [Determination of dimethylbenzoic acid isomers in urine by gas chromatography].

    PubMed

    Kostrzewski, P; Wiaderna-Brycht, A; Czerski, B

    1994-01-01

    Trimethylobenzene (TMB) is a main ingredient of many organic solvents used in industry. In Farbasol (Polish trade name of the solvent) TMB occurs as a mixture of three isomers: pseudocumene (1, 2, 4-TMB) 30%; mesitylene (1, 3, 5-TMB) 15%; hemimellitene (1,2,3-TMB) 5%. As it is known in human organism, TMB is metabolized mainly to dimethylbenzoic (DMBA) and dimethylhippuric (DMHA) acids, and some authors suggest, that the acids excreted in urine can be biological indicators of exposure to TMB. This study was aimed at developing the method of determination of DMBA isomers in urine. Biological material was hydrolyzed with sodium hydroxide and next extracted with diethyl ether. DMBA concentration in urine was determined by gas chromatography using a variant of quantitative analysis with internal standard (5-methyl-2-isopropylphenol, thymol). Analytical parameters of the developed method of determination of DMBA isomers in urine such as linearity, precision, reproducibility, stability (192 days, when urine samples stored at-18 degrees C), detectability limit (400 micrograms/dm3) have been fully compatible with the requirements of biological monitoring. In order to confirm the presence of DMBA isomers in urine, four volunteers were exposed (8 hours) to Farbasol in toxicological chamber. The TMB concentration in the air, determined by means of gas chromatograph (HP 5890), amounted to 100 mg/m3 (MAC value in Poland). In urine samples collected 2,3-; 2,4-; 2,5-; 2,6-; 3,4-; 3,5-dimethylbenzoic acids were identified by means of GC/MSD.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8170375

  6. Ammonia Gas Sensing Behavior of Tanninsulfonic Acid Doped Polyaniline-TiO2 Composite

    PubMed Central

    Bairi, Venu Gopal; Bourdo, Shawn E.; Sacre, Nicolas; Nair, Dev; Berry, Brian C.; Biris, Alexandru S.; Viswanathan, Tito

    2015-01-01

    A highly active tannin doped polyaniline-TiO2 composite ammonia gas sensor was developed and the mechanism behind the gas sensing activity was reported for the first time. A tanninsulfonic acid doped polyaniline (TANIPANI)-titanium dioxide nanocomposite was synthesized by an in situ polymerization of aniline in the presence of tanninsulfonic acid and titanium dioxide nanoparticles. X-ray diffraction and thermogravimetric analysis were utilized to determine the incorporation of TiO2 in TANIPANI matrix. UV-Visible and infrared spectroscopy studies provided information about the electronic interactions among tannin, polyaniline, and TiO2. Scanning electron microscopy (SEM) along with energy dispersive X-ray spectroscopy (EDS) and atomic force microscopy (AFM) surface analysis techniques were used to investigate the metal oxide dispersions inside polyaniline matrix. Gas sensors were prepared by spin coating solutions of TANIPANI-TiO2 and TANIPANI composites onto glass slides. Sensors were tested at three different concentrations (20 ppm, 40 ppm, and 60 ppm) of ammonia gas at ambient temperature conditions by measuring the changes in surface resistivity of the films with respect to time. Ammonia gas sensing plots are presented showing the response values, response times and recovery times. The TANIPANI-TiO2 composite exhibited better response and shorter recovery times when compared to TANIPANI control and other polyaniline composites that have been reported in the literature. For the first time a proposed mechanism of gas sensing basing on the polaron band localization and its effects on the gas sensing behavior of polyaniline are reported. PMID:26501291

  7. Differentiation of free-living Anabaena and Nostoc cyanobacteria on the basis of fatty acid composition.

    PubMed

    Caudales, R; Wells, J M

    1992-04-01

    The cellular fatty acids of free-living, nitrogen-fixing cyanobacteria belonging to the genera Anabaena and Nostoc were analyzed to differentiate the genera. The fatty acid compositions of 10 Anabaena strains and 10 Nostoc strains that were grown for 12 days on BG-11o medium were determined by gas-liquid chromatography-mass spectroscopy. Of the 53 fatty acids detected, 17 were major components; the average level for each of these 17 fatty acids was at least 0.9% of the total fatty acids (in at least one of the genera). These fatty acids included (with mean percentages in the Anabaena and Nostoc strains, respectively) the saturated fatty acids 16:0 (30.55 and 23.23%) and 18:0 (0.77 and 1.27%); several unsaturated fatty acids, including 14:1 cis-7 (2.50 and 0.11%), 14:1 cis-9 (3.10 and 3.41%), a polyunsaturated 16-carbon (sites undetermined) fatty acid with an equivalent chain length of 15.30 (1.20 and 1.03%), 16:4 cis-4 (0.95 and 0.87%), 16:3 cis-6 (2.16 and 1.51%), 16:1 cis-7 (1.44 and 0.36%), 16:1 cis-9 (6.53 and 18.76%), 16:1 trans-9 (4.02 and 1.35%), 16:1 cis-11 (1.62 and 0.42%), 18:2 cis-9 (10.16 and 12.44%), 18:3 cis-9 (18.19 and 17.25%), 18:1 cis-9 (4.01 and 5.10%), and 18:1 trans-9 (0.92 and 1.94%); and the branched-chain fatty acids iso-16:0 (2.50 and 1.14%) and iso-15:1 (0.34 and 2.05%).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1581185

  8. Thermal and Mechanical Characteristics of Polymer Composites Based on Epoxy Resin, Aluminium Nanopowders and Boric Acid

    NASA Astrophysics Data System (ADS)

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

    2016-01-01

    The epoxy polymers are characterized by low thermal stability and high flammability. Nanoparticles are considered to be effective fillers of polymer composites for improving their thermal and functional properties. In this work, the epoxy composites were prepared using epoxy resin ED-20, polyethylene polyamine as a hardener, aluminum nanopowder and boric acid fine powder as flame-retardant filler. The thermal characteristics of the obtained samples were studied using thermogravimetric analysis and differential scanning calorimetry. The mechanical characteristics of epoxy composites were also studied. It was found that an addition of all fillers enhances the thermal stability and mechanical characteristics of the epoxy composites. The best thermal stability showed the epoxy composite filled with boric acid. The highest flexural properties showed the epoxy composite based on the combination of boric acid and aluminum nanopowder.

  9. Computer-assisted Gran titration procedure for strong acid determination

    SciTech Connect

    Phillips, M.F.; Gaffney, J.S.; Goodrich, R.W.; Tanner, R.L.

    1984-10-01

    An automated method for determining, by coulometric titration, small amounts of strong acid in the presence of weak acids is given. Essentially, a pH meter and a coulometer are coupled with a Tektronix 4052 mini-computer, and a two-step computer program then directs the titration and calculates the equivalence point by the method of Gran. A comparison of precision and accuracy of results for test solutions by manual and automated data reduction methods is presented. The method is being used successfully to analyze for the H/sup +/ content in ambient aerosol samples from aerometric field experiments, and can be used for cloud and rainwater samples as well. 3 references, 1 figure, 1 table.

  10. Rapid simultaneous determination of organic acids, free amino acids, and lactose in cheese by capillary electrophoresis.

    PubMed

    Izco, J M; Tormo, M; Jiménez-Flores, R

    2002-09-01

    A capillary electrophoresis (CE) method for the simultaneous separation of 11 metabolically important organic acids (oxalic, formic, citric, succinic, orotic, uric, acetic, pyruvic, propionic, lactic, and butyric), 10 amino acids (Asp, Glu, Tyr, Gly, Ala, Ser, Leu, Phe, Lys, and Trp), and lactose has been optimized, validated, and tested in dairy products. Repeatability and linearity were calculated for each compound, with detection limit values as low as 0.2 x 10(-2) mM for citric acid and Gly. The method was applied to analyze yogurt and different varieties of commercial cheeses. This method yielded specific CE patterns for different varieties of cheese. Also, it has been shown to be sensitive enough to measure small changes in composition of some of those compounds in fresh cheese stored under accelerated ripening conditions for 2 d at 32 degrees C (e.g., from 1728.3 +/- 45.0 to 1166.7 +/- 4.5 mg/100 g of DM in the case of lactose, or from 23.5 +/- 0.6 to 76.8 +/- 16.7 mg/100 g of DM in the case of acetic acid).

  11. Comparison of compositional characteristics of amino acids between livestock wastewater and carcass leachate.

    PubMed

    Choi, Jong-Woo; Kim, Jee-Young; Nam, Yong-Jae; Lee, Won-Seok; Han, Jin-Seok

    2013-11-01

    This study was purposed to examine the use of amino acids as an indicator to determine whether groundwater around carcass burial sites is polluted by livestock wastewater (LW) or carcass leachate (CL). The analysis of samples showed that the average amino acid concentration of carcass leachate (531.897 mg/L; 4341.784 μmol/L) was about 300 times as high as that of livestock wastewater (1.755 mg/L; 16.283 μmol/L). To identify distinct characteristics between LW and CL, six amino acids were paired with one another to calculate their relative composition ratios, which were found to be Leu/Trp (CL 8.39∼98.6, LW 0.89∼4.77), Val/Trp (CL 11.95∼175.38, LW 0.73∼3.62), Lys/Leu (CL 0.01∼0.72, LW 0.96∼8.44), Lys/Ile (CL 0.02∼1.55, LW 1.64∼10.99), Met/Lys (CL 0.14∼0.45, LW 0.03∼0.14), and Ile/Val (CL 0.38∼0.73, LW 0.40∼0.97). The hierarchical clustering result showed that the similarity was 0.617 among the seven LW samples and 0.563 among the seven CL samples, while the similarity between LW and CL samples was 0.198, presenting that these two sources are distinct from each other. All these results indicate that amino acids can be used as a tracer to evaluate if the contamination source is livestock wastewater or carcass leachate. To apply amino acids to tracing pollutants more effectively, however, further studies are needed to understand whether the relative abundance ratios of amino acids are maintained as they are transporting through soils as a medium.

  12. Evaluation of the novel three-dimensional porous poly (L-lactic acid)/nano-hydroxyapatite composite scaffold.

    PubMed

    Huang, Jianghong; Xiong, Jianyi; Liu, Jianquan; Zhu, Weimin; Chen, Jielin; Duan, Li; Zhang, Jufeng; Wang, Daping

    2015-01-01

    To determine the optimal ratio of nano-hydroxyapatite (n-HA) to polylactic acid (PLLA) in the novel three-dimensional porous PLLA/n-HA composite scaffolds, low-temperature rapid prototyping technology was employed to fabricate the composite materials with different n-HA contents. Mechanical properties and degradation behaviors of the composites were examined, and the scaffold microstructure and n-HA dispersion were observed by scanning electron microscope (SEM). Mechanical tests demonstrated that the tensile strength of the composite material gradually decreased with an increase in n-HA content. When the n-HA content reached 20 wt%, the bending strength of the composite material peaked at 138.5 MPa. SEM images demonstrated that the optimal content of n-HA was 20 wt% as the largest interconnected pore size that can be seen, with a porosity as high as 80%. In vitro degradation experiments demonstrated that the pH value of the material containing solution gradually decreased in a time-dependent manner, with a simultaneous weakening of the mechanical properties. In vitro study using rat osteoblast cells showed that the composite scaffolds were biocompatible; the 20 wt% n-HA scaffold offered particular improvement to rat osteoblast cell adhesion and proliferation compared to other compositions. It was therefore concluded that 20 wt% n-HA is the optimal nano-hydroxyapatite (n-HA) to polylactic acid (PLLA) ratio, with promise for bone tissue engineering. PMID:26405972

  13. Evaluation of the novel three-dimensional porous poly (L-lactic acid)/nano-hydroxyapatite composite scaffold.

    PubMed

    Huang, Jianghong; Xiong, Jianyi; Liu, Jianquan; Zhu, Weimin; Chen, Jielin; Duan, Li; Zhang, Jufeng; Wang, Daping

    2015-01-01

    To determine the optimal ratio of nano-hydroxyapatite (n-HA) to polylactic acid (PLLA) in the novel three-dimensional porous PLLA/n-HA composite scaffolds, low-temperature rapid prototyping technology was employed to fabricate the composite materials with different n-HA contents. Mechanical properties and degradation behaviors of the composites were examined, and the scaffold microstructure and n-HA dispersion were observed by scanning electron microscope (SEM). Mechanical tests demonstrated that the tensile strength of the composite material gradually decreased with an increase in n-HA content. When the n-HA content reached 20 wt%, the bending strength of the composite material peaked at 138.5 MPa. SEM images demonstrated that the optimal content of n-HA was 20 wt% as the largest interconnected pore size that can be seen, with a porosity as high as 80%. In vitro degradation experiments demonstrated that the pH value of the material containing solution gradually decreased in a time-dependent manner, with a simultaneous weakening of the mechanical properties. In vitro study using rat osteoblast cells showed that the composite scaffolds were biocompatible; the 20 wt% n-HA scaffold offered particular improvement to rat osteoblast cell adhesion and proliferation compared to other compositions. It was therefore concluded that 20 wt% n-HA is the optimal nano-hydroxyapatite (n-HA) to polylactic acid (PLLA) ratio, with promise for bone tissue engineering.

  14. Determining the Δ47 acid fractionation in dolomites

    NASA Astrophysics Data System (ADS)

    Murray, Sean T.; Arienzo, Monica M.; Swart, Peter K.

    2016-02-01

    This paper reports the fractionation of Δ47 during the digestion of dolomite in phosphoric acid between 25 °C and 90 °C using five different samples, including three of Pliocene age from the Bahamas, one from the Jurassic in the Middle East, and one obtained from the National Institute of Standards (NIST 88b). The composition of the dolomites analyzed varied from Ca0.56Mg0.44CO3 to Ca0.50Mg0.50CO3. Fractionation values were also compared between the common acid bath and sealed vessel techniques at various temperatures. No statistically significant differences were observed either between these two methods or as a function of the dolomite's stoichiometry. These data produce a difference in fractionation of 0.153 ± 0.011‰ for dolomite samples digested at 90 °C compared to those reacted at 25 °C, a value higher and statistically different to previously published values. Utilization of this value in a study of dolomites from a core drilled on the island of San Salvador in the Bahamas yielded temperatures and δ18Ofluid values which agree with previous interpretations on the formation of these dolomites. Application of this value to other published studies produces lower estimates of temperature and δ18Ofluid values for the dolomitization process that are more consistent with the geologic models suggested for these studies.

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

    SciTech Connect

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

    1984-01-01

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

  16. Compositions and method for controlling precipitation when acidizing sour wells

    SciTech Connect

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

    1990-08-21

    This patent describes a method of treating a sour well penetrating a subterranean formation. It comprises: introducing into the well a treating fluid comprising an acid solution having a pH below 1.9, an iron sequestering agent 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 comprising at least one compound selected from the group consisting of an aldehyde, acetal, hemiacetal and any other compound capable of forming aldehydes in the acid solution, present in an amount of from about 0.25 to about 5 percent of the acid solution; and treating the subterranean formation with the treating fluid.

  17. Determination of enoxacin using Tb composite nanoparticles sensitized luminescence method.

    PubMed

    Karim, Mohammad Mainul; Lee, Sang Hak

    2008-09-01

    In our study, terbium-acetylacetone (Tb-acac) composite nanoparticles have been prepared under vigorous ultrasonic irradiation. The nanoparticles are water soluble, stable and have extremely narrow emission bands and high internal quantum efficiencies. They were used as fluorescence probes in the determination of enoxacin (Enox) based on the fluorescence enhancement of nanoparticles through fluorescence resonance energy transfer (FRET). The influence of buffer solution on the fluorescence intensity was investigated. Under the optimum conditions, the fluorescence intensity of the Tb-acac-Enox system is linearly proportional to the Enox concentration in the Enox concentration range of 2 x 10(-7)-1 x 10(-4) M. The correlation coefficient for the calibration curve was 0.9976. The limit of detection as defined by IUPAC, C (LOD) = 3S (b)/m (where S (b) is the standard deviation of the blank signals and m is the slope of the calibration graph) was found to be 3 x 10(-8) M. The relative standard deviation (RSD) for six repeated measurements of 1 x 10(-4) M Enox was 1.35%. The method was applied to the determination of Enox in pharmaceutical formulation and recovery results were obtained from urine samples.

  18. ION-EXCLUSION CHROMATOGRAPHIC DETERMINATION OF CARBOXYLIC ACIDS USED TO SUPPORT THE MICROBIALLY MEDIATED REDUCTIVE DECHLORINATION OF TETRACHLOROETHENE

    EPA Science Inventory

    An analytical method was developed for the determination of lactic acid, formic acid, acetic acid, propionic acid, and butyric acid in environmental microcosm samples using ion-exclusion chromatography. The chromatographic behavior of various eluents was studied to determine the ...

  19. Analysis of the porcine APOA2 gene expression in liver, polymorphism identification and association with fatty acid composition traits.

    PubMed

    Ballester, M; Revilla, M; Puig-Oliveras, A; Marchesi, J A P; Castelló, A; Corominas, J; Fernández, A I; Folch, J M

    2016-10-01

    APOA2 is a protein implicated in triglyceride, fatty acid and glucose metabolism. In pigs, the APOA2 gene is located on pig chromosome 4 (SSC4) in a QTL region affecting fatty acid composition, fatness and growth traits. In this study, we evaluated APOA2 as a candidate gene for meat quality traits in an Iberian × Landrace backcross population. The APOA2:c.131T>A polymorphism, located in exon 3 of APOA2 and determining a missense mutation, was associated with the percentage of hexadecenoic acid [C16:1(n-9)], linoleic acid [C18:2(n-6)], α-linolenic acid [C18:3(n-3)], dihomo-gamma-linolenic acid [C20:3(n-6)] and polyunsaturated fatty acids (PUFAs) in backfat. Furthermore, this SNP was associated with the global mRNA expression levels of APOA2 in liver and was used as a marker to determine allelic expression imbalance by pyrosequencing. We determined an overexpression of the T allele in heterozygous samples with a mean ratio of 2.8 (T/A), observing a high variability in the allelic expression among individuals. This result suggests that complex regulatory mechanisms, beyond a single polymorphism (e.g. epigenetic effects or multiple cis-acting polymorphisms), may be regulating APOA2 gene expression.

  20. Wheat gluten amino acid composition analysis by high-performance anion-exchange chromatography with integrated pulsed amperometric detection.

    PubMed

    Rombouts, Ine; Lamberts, Lieve; Celus, Inge; Lagrain, Bert; Brijs, Kristof; Delcour, Jan A

    2009-07-17

    A simple accurate method for determining amino acid composition of wheat gluten proteins and their gliadin and glutenin fractions using high-performance anion-exchange chromatography with integrated pulsed amperometric detection is described. In contrast to most conventional methods, the analysis requires neither pre- or post-column derivatization, nor oxidation of the sample. It consists of hydrolysis (6.0M hydrochloric acid solution at 110 degrees C for 24h), evaporation of hydrolyzates (110 degrees C), and chromatographic separation of the liberated amino acids. Correction factors (f) accounted for incomplete cleavage of peptide bonds involving Val (f=1.07) and Ile (f=1.13) after hydrolysis for 24h and for Ser (f=1.32) losses during evaporation. Gradient conditions including an extra eluent (0.1M acetic acid solution) allowed multiple sequential sample analyses without risk of Glu contamination on the anion-exchange column. While gluten amino acid compositions by the present method were mostly comparable to those obtained by a conventional method involving oxidation, acid hydrolysis and post-column ninhydrin derivatization, the latter method underestimated Tyr, Val and Ile levels. Results for the other amino acids obtained by the different methods were linearly correlated (r>0.99, slope=1.03).

  1. Fast mass spectrometry-based enantiomeric excess determination of proteinogenic amino acids.

    PubMed

    Fleischer, Heidi; Thurow, Kerstin

    2013-03-01

    A rapid determination of the enantiomeric excess of proteinogenic amino acids is of great importance in various fields of chemical and biologic research and industries. Owing to their different biologic effects, enantiomers are interesting research subjects in drug development for the design of new and more efficient pharmaceuticals. Usually, the enantiomeric composition of amino acids is determined by conventional analytical methods such as liquid or gas chromatography or capillary electrophoresis. These analytical techniques do not fulfill the requirements of high-throughput screening due to their relative long analysis times. The method presented allows a fast analysis of chiral amino acids without previous time consuming chromatographic separation. The analytical measurements base on parallel kinetic resolution with pseudoenantiomeric mass tagged auxiliaries and were carried out by mass spectrometry with electrospray ionization. All 19 chiral proteinogenic amino acids were tested and Pro, Ser, Trp, His, and Glu were selected as model substrates for verification measurements. The enantiomeric excesses of amino acids with non-polar and aliphatic side chains as well as Trp and Phe (aromatic side chains) were determined with maximum deviations of the expected value less than or equal to 10ee%. Ser, Cys, His, Glu, and Asp were determined with deviations lower or equal to 14ee% and the enantiomeric excess of Tyr were calculated with 17ee% deviation. The total screening process is fully automated from the sample pretreatment to the data processing. The method presented enables fast measurement times about 1.38 min per sample and is applicable in the scope of high-throughput screenings.

  2. Fast mass spectrometry-based enantiomeric excess determination of proteinogenic amino acids.

    PubMed

    Fleischer, Heidi; Thurow, Kerstin

    2013-03-01

    A rapid determination of the enantiomeric excess of proteinogenic amino acids is of great importance in various fields of chemical and biologic research and industries. Owing to their different biologic effects, enantiomers are interesting research subjects in drug development for the design of new and more efficient pharmaceuticals. Usually, the enantiomeric composition of amino acids is determined by conventional analytical methods such as liquid or gas chromatography or capillary electrophoresis. These analytical techniques do not fulfill the requirements of high-throughput screening due to their relative long analysis times. The method presented allows a fast analysis of chiral amino acids without previous time consuming chromatographic separation. The analytical measurements base on parallel kinetic resolution with pseudoenantiomeric mass tagged auxiliaries and were carried out by mass spectrometry with electrospray ionization. All 19 chiral proteinogenic amino acids were tested and Pro, Ser, Trp, His, and Glu were selected as model substrates for verification measurements. The enantiomeric excesses of amino acids with non-polar and aliphatic side chains as well as Trp and Phe (aromatic side chains) were determined with maximum deviations of the expected value less than or equal to 10ee%. Ser, Cys, His, Glu, and Asp were determined with deviations lower or equal to 14ee% and the enantiomeric excess of Tyr were calculated with 17ee% deviation. The total screening process is fully automated from the sample pretreatment to the data processing. The method presented enables fast measurement times about 1.38 min per sample and is applicable in the scope of high-throughput screenings. PMID:23232768

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

    NASA Astrophysics Data System (ADS)

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

    2012-11-01

    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.

  4. 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.

    PubMed

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

    1997-06-01

    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 OM to water and the production of eicosanoids in skin and gills challenged with the Ca2+ ionophore A23187 were also measured. Phospholipid (PL) fatty acid compositions were substantially modified in EFA-deficient fish, with increased saturated fatty acids and decreased polyunsaturated fatty acids (PUFA), especially arachidonic acid (AA) and eicosapentaenoic acid (EPA), while docosahexaenoic acid (DHA) was largely retained. The onset of EFA deficiency was shown by the appearance of n-9 PUFA, particularly 20:3n-9. The main effects of EFA deficiency on phosphatidylcholine (PC) and phosphatidylethanolamine (PE) were to increase saturated fatty acids and monoenes, especially 16:1 and 18:1, and to decrease EPA and DHA. The content of DHA in phosphatidylserine (PS) was high in control animals (40% in skin and 35% in opercular membrane) and was mostly retained in EFA deficient animals. Arachidonic acid (AA) was the most abundant PUFA esterified to phosphatidylinositol (PI) and was significantly reduced in EFA deficient animals (from 31% to 13% in skin), where a large amount of 20:3n-9 (9% in skin) was also present. Influxes and effluxes of water through skin and opercular membrane were measured in vitro. No differences were detected between rainbow trout fed the control or the EFA deficient diet. 12-Hydroxyeicosatetraenoic acid (12-HETE), 12-hydroxyeicosapentaenoic acid (12-HEPE) and 14-hydroxydocosahexaenoic acid (14-HDHE) could not be detected in skin from control or EFA deficient fish. There was no difference between control and EFA deficient trout in the levels of leukotriene C

  5. Fatty acid composition of erythrocyte membrane lipid obtained from children suffering from kwashiorkor and marasmus.

    PubMed

    Vajreswari, A; Narayanareddy, K; Rao, P S

    1990-08-01

    The fatty acid composition of erythrocyte membrane (EM) lipids obtained from normal, kwashiorkor, and marasmic children was analyzed by gas chromatography. The proportion of palmitic acid (16:0) was lower and of oleic acid (18:1) higher in the kwashiorkor group than in the control group. The marasmic group showed lower proportions of eicosatrienoic acid (20:3) and arachidonic acid (20:4) and a higher proportion of oleic acid (18:1) than the control group. A significant difference was found between the marasmic and kwashiorkor groups with respect to arachidonic acid (20:4), which showed a lower proportion in the former group than the latter. The ratio of arachidonic acid to linoleic acid (20:4/18:2) was markedly lower in the marasmic group than the control group, suggesting a possible impairment in the conversion of linoleic acid to arachidonic acid in marasmic children. The ratio of unsaturated fatty acids to saturated fatty acids was markedly elevated in the kwashiorkor group over that of control group, indicating increased fluidity of EM in kwashiorkor. It is suggested that the altered membrane fatty acid composition reflects deranged lipid metabolism and affects the physical and physiological properties of EM and could contribute to changes in the activities of several red blood cell membrane-bound enzymes reported earlier in kwashiorkor children.

  6. Effect of oil type and fatty acid composition on dynamic and steady shear rheology of vegetable oils.

    PubMed

    Yalcin, Hasan; Toker, Omer Said; Dogan, Mahmut

    2012-01-01

    In this study, effect of fatty acid composition on dynamic and steady shear rheology of oils was studied. For this aim, different types of vegetable oils (soybean, sunflower, olive, hazelnut, cottonseed and canola), were used. Rheological properties of oil samples were identified by rheometer (Thermo-Haake) at 25°C and fatty acid composition of oils was determined by GC (Agilent 6890). Steady shear rheological properties of oil samples were measured at shear rate range of 0.1-100 s⁻¹. Viscosity of olive, hazelnut, cottonseed, canola, soybean and sunflower was 61.2 mPa.s, 59.7 mPa.s, 57.3 mPa.s, 53.5 mPa.s, 48.7 mPa.s and 48.2 mPa.s, respectively. There was a significant difference between viscosity of oils except soybean and sunflower. As a result it was seen that there was a correlation between viscosity and monounsaturated (R=0.89), polyunsaturated (R=-0.97) fatty acid composition of oils, separately. Equation was found to predict viscosity of the oils based on mono and polyunsaturation composition of oils. In addition the dynamic rheological properties of oils were also examined. G', G'' and tan δ (G''/G') values were measured at 0.3 Pa (in viscoelastic region) and 0.1-1 Hz. As a result of multiple regression analysis another equations were found between tan δ, viscosity and polyunsaturated fatty acids.

  7. A Study on Amino Acids: Synthesis of Alpha-Aminophenylacetic Acid (Phenylglycine) and Determination of its Isoelectric Point.

    ERIC Educational Resources Information Center

    Barrelle, M.; And Others

    1983-01-01

    Background information and procedures are provided for an experimental study on aminophenylacetic acid (phenylglycine). These include physical chemistry (determination of isoelectric point by pH measurement) and organic chemistry (synthesis of an amino acid in racemic form) experiments. (JN)

  8. Erythrocyte Membrane Fatty Acid Composition in Premenopausal Patients with Iron Deficiency Anemia.

    PubMed

    Aktas, Mehmet; Elmastas, Mahfuz; Ozcicek, Fatih; Yilmaz, Necmettin

    2016-01-01

    Iron deficiency anemia (IDA) is one of the most common nutritional disorders in the world. In the present study, we evaluated erythrocyte membrane fatty acid composition in premenopausal patients with IDA. Blood samples of 102 premenopausal women and 88 healthy control subjects were collected. After the erythrocytes were separated from the blood samples, the membrane lipids were carefully extracted, and the various membrane fatty acids were measured by gas chromatography (GC). Statistical analyses were performed with the SPSS software program. We used blood ferritin concentration <15 ng/mL as cut-off for the diagnosis of IDA. The five most abundant individual fatty acids obtained were palmitic acid (16:0), oleic acid (18:1, n-9c), linoleic acid (18:2, n-6c), stearic acid (18:0), and erucic acid (C22:1, n-9c). These compounds constituted about 87% of the total membrane fatty acids in patients with IDA, and 79% of the total membrane fatty acids in the control group. Compared with control subjects, case patients had higher percentages of palmitic acid (29.9% case versus 25.3% control), oleic acid (16.8% case versus 15.1% control), and stearic acid (13.5% case versus 10.5% control), and lower percentages of erucic acid (11.5% case versus 13.6% control) and linoleic acid (15.2% case versus 15.4% control) in their erythrocyte membranes. In conclusion, the total-erythrocyte-membrane saturated fatty acid (SFA) composition in premenopausal women with IDA was found to be higher than that in the control group; however, the total-erythrocyte-membrane unsaturated fatty acid (UFA) composition in premenopausal women with IDA was found to be lower than that in the control group. The differences in these values were statistically significant.

  9. Advances in the Determination of Nucleic Acid Conformational Ensembles

    NASA Astrophysics Data System (ADS)

    Salmon, Loïc; Yang, Shan; Al-Hashimi, Hashim M.

    2014-04-01

    Conformational changes in nucleic acids play a key role in the way genetic information is stored, transferred, and processed in living cells. Here, we describe new approaches that employ a broad range of experimental data, including NMR-derived chemical shifts and residual dipolar couplings, small-angle X-ray scattering, and computational approaches such as molecular dynamics simulations to determine ensembles of DNA and RNA at atomic resolution. We review the complementary information that can be obtained from diverse sets of data and the various methods that have been developed to combine these data with computational methods to construct ensembles and assess their uncertainty. We conclude by surveying RNA and DNA ensembles determined using these methods, highlighting the unique physical and functional insights obtained so far.

  10. Green chromatography determination of fatty acid methyl esters in biodiesel.

    PubMed

    Mayo, Carlos Molina; Alayón, Andrea Brito; García Rodríguez, María Teresa; Jiménez Abizanda, Ana Isabel; Moreno, Francisco Jiménez

    2015-01-01

    This work proposes a green, simple and rapid chromatographic methodology for separation and determination of a group of 13 fatty acids methyl esters (FAMEs) by using a capillary gas chromatography with a flame ionization detector. The method was successfully applied for the determination of FAMEs in biodiesel samples from commercial and waste cooking oils, synthesized by homogeneous catalysis. Detection and quantification limits were in the μg L(-1) level. Direct injection of sample solution was compared with solid-phase extraction and solid-phase microextraction procedures, giving similar results. The lower analysis time represent considerable improvement compared with other papers. The described methodology is especially suitable for process control applications. The samples analysed showed total contents of FAMEs higher than 96.5%, which verifies the European regulations. PMID:25666201

  11. Polarographic determination of metyrosine through treatment with nitrous acid.

    PubMed

    Aly, F A; Belal, F; el-Brashy, A

    1993-10-15

    A simple and sensitive polarographic method is described for the determination of metyrosine through treatment with nitrous acid. The different experimental parameters affecting the derivatization process, as well as the polarographic analysis were studied. The derivatization product was found to be reducible at the dropping mercury electrode over the whole pH range in Britton Robinson buffers. At pH 5, a well-defined diffusion-controlled cathodic wave was produced. The limiting current versus the concentration plot was linear over the range 8-80 mumol/l in the direct current mode with a detection limit of 0.2 mumol/l. The method was then applied to the determination of metyrosine capsules, and the results obtained were in good agreement with those given by the USP method.

  12. In vitro bioactivity assessment of composite membrane containing antimicrobial lauric acid for guided bone regeneration in dental application

    NASA Astrophysics Data System (ADS)

    Suleiman, Muhammad Jabir; Kalitheertha, Jamuna Thevi; Sabri, Siti Noorzidah

    2015-07-01

    The manuscript reflect research work in fabrication of a triple layered composite membrane and to perform an in vitro bioactivity evaluation on composite membrane containing antimicrobial lauric acid. Poly(lactic-co-glycolic acid) (PLGA) matrix was incorporated with various amounts of nanoapatite (NAp) and lauric acid (LA) to form a triple-layered composite membrane. This membrane was prepared using a single step fabrication technique comprising of solvent casting, thermally induced phase separation and solvent leaching processes. Apatite mineralization was detected on the composite membranes within 30 days of exposure to simulated body fluid (SBF) and showed increased apatite formation at 30-60wt% of NAp content in the PLGA matrix on layer 3 (L3), that has the highest amount of NAp compared with layer 1 (L1) and layer 2 (L2) of the membrane. However, apatite mineralization was not detected on pure PLGA membrane. In addition, incorporation of LA on L1 and L2 has no influence on apatite mineral formation as none detected on these surfaces. The presence of NAp determines the formation of apatite crystals on the composite membrane. These membranes with triple layered design and bioactive properties showed potential use for guided bone regeneration purposes in dental application.

  13. Variability of oil content and of major fatty acid composition in almond (Prunus amygdalus Batsch) and its relationship with kernel quality.

    PubMed

    Kodad, O; Socias I Company, R

    2008-06-11

    Oil content and fatty acid composition were determined for two years in the kernel oil of eight cultivars and 47 advanced self-compatible almond genotypes developed in an almond breeding program. Considerable variation between genotypes was found for all parameters. Oil content ranged from 48% to 67% of the total kernel dry weight but was consistent over the two years. Fatty acid composition was also very variable, with significant differences between genotypes, even in genotypes of the same progeny. Oleic acid, ranging from 63% to 78%, and linoleic acid, ranging from 12% to 27%, were the major fatty acids, showing higher values in some selections than in their parents. The large variability observed for all fatty acids and the presence of selections with higher oil and fatty acid contents than the commercial cultivars represents a very promising base to obtain new almond cultivars with oil of higher quality, satisfying the industrial and consumer sectors.

  14. Fatty acid composition of spermatozoa is associated with BMI and with semen quality.

    PubMed

    Andersen, J M; Rønning, P O; Herning, H; Bekken, S D; Haugen, T B; Witczak, O

    2016-09-01

    High body mass index (BMI) is negatively associated with semen quality. In addition, the composition of fatty acids of spermatozoa has been shown to be important for their function. The aim of the study was to examine the association between BMI and the composition of spermatozoa fatty acids in men spanning a broad BMI range. We also analysed the relation between fatty acid composition of spermatozoa and semen characteristics, and the relationship between serum fatty acids and spermatozoa fatty acids. One hundred forty-four men with unknown fertility status were recruited from the general population, from couples with identified female infertility and from morbid obesity centres. Standard semen analysis (WHO) and sperm DNA integrity (DFI) analysis were performed. Fatty acid compositions were assessed by gas chromatography. When adjusted for possible confounders, BMI was negatively associated with levels of sperm docosahexaenoic acid (DHA) (p < 0.001) and palmitic acid (p < 0.001). The amount of sperm DHA correlated positively with total sperm count (r = 0.482), sperm concentration (r = 0.469), sperm vitality (r = 0.354), progressive sperm motility (r = 0.431) and normal sperm morphology (r = 0.265). A negative association was seen between DHA levels and DNA fragmentation index (r = -0.247). Levels of spermatozoa palmitic acid correlated positively with total sperm count (r = 0.227), while levels of linoleic acid correlated negatively (r = -0.254). When adjusted for possible confounders, only the levels of arachidonic acid showed positive correlation between spermatozoa and serum phospholipids (r = 0.262). Changes in the fatty acid composition of spermatozoa could be one of the mechanisms underlying the negative association between BMI and semen quality. The relationship between fatty acids of spermatozoa and serum phospholipids was minor, which indicates that BMI affects fatty acid composition of spermatozoa through regulation of fatty acid

  15. Improved liquid chromatographic method for determination of organic acids in leaves, pulp, fruits, and rinds of Garcinia.

    PubMed

    Jayaprakasha, Guddadarangavvanahally K; Jena, Bhabani S; Sakariah, Kunnumpurath K

    2003-01-01

    An improved liquid chromatographic (LC) method was developed for determination of organic acids in leaves, pulp, fruits, and rinds of Garcinia. At present, the commonly used LC method for analysis of organic acids in Garcinia extracts uses direct application of the extracts on the column. This practice gradually reduces efficiency of the column and shortens its life. In the improved method, the interfering substances such as pigments and xanthones were effectively removed by passing the aqueous extract through an ODS cartridge. With subsequent injection on a C18 reversed-phase column, using 6.0 mM phosphoric acid as the mobile phase with a flow rate of 1.0 mL/min and UV detection at 210 nm, the organic acids were determined in the extracts. The major organic acid was (-)-hydroxycitric acid at the level of 2.5, 0.8, 3.0, and 20.1% in leaf, pulp, fresh fruit, and dried rinds, respectively. Minor quantities of hydroxycitric acid lactone, oxalic acid, and citric acid were also identified. Limits of detection and recoveries were 0.9-1.5 microg and 93.9-99.8%, respectively. This is the first report on the composition of organic acids from Garcinia pedunculata.

  16. Fatty acid composition of Euphausia superba, Thysanoessa macrura and Euphausia crystallorophias collected from Prydz Bay, Antarctica

    NASA Astrophysics Data System (ADS)

    Yang, Guang; Li, Chaolun; Wang, Yanqing

    2016-04-01

    The information of trophic relationship is important for studying the Southern Ocean ecosystems. In this study, three dominant krill species, Euphausia superba, Thysanoessa macrura and Euphausia crystallorophias, were collected from Prydz Bay, Antarctica, during austral summer of 2009/2010. The composition of fatty acids in these species was studied. E. superba and T. macrura showed a similar fatty acid composition which was dominated by C14:0, C16:0, EPA (eicosapentenoic acid) and DHA (decosahexenoic acid) while E. crystallorophias showed higher contents of C18:1(n-9), C18:1(n-7), DHA and EPA than the former two. Higher fatty acid ratios of C18:1(n-9)/18:1(n-7), PUFA (polyunsaturated fatty acid)/SFA (saturated fatty acid), and 18PUFA/16PUFA indicated that E. crystallorophias should be classified as a typical omnivore with a higher trophic position compared with E. superba and T. macrura.

  17. Potentiometric determination of the total acidity of humic acids by constant-current coulometry.

    PubMed

    Palladino, Giuseppe; Ferri, Diego; Manfredi, Carla; Vasca, Ermanno

    2007-01-16

    A straightforward method for both the quantitative and the equilibrium analysis of humic acids in solution, based on the combination of potentiometry with coulometry, is presented. The method is based on potentiometric titrations of alkaline solutions containing, besides the humic acid sample, also NaClO(4) 1M; by means of constant current coulometry the analytical acidity in the solutions is increased with a high precision, until the formation of a solid phase occurs. Hence, the total acid content of the macromolecules may be determined from the e.m.f. data by using modified Gran plots or least-squares sum minimization programs as well. It is proposed to use the pK(w) value in the ionic medium as a check of the correctness of each experiment; this datum may be readily obtained as a side-result in each titration. Modelling acid-base equilibria of the HA samples analysed was also performed, on the basis of the buffer capacity variations occurring during each titration. The experimental data fit, having the least standard deviation, was obtained assuming a mixture of three monoprotic acids (HX, HY, HZ) having about the same analytical concentration, whose acid dissociation constants in NaClO(4) 1M at 25 degrees C were pK(HX)=3.9+/-0.2, pK(HY)=7.5+/-0.3, pK(HZ)=9.5+/-0.2, respectively. With the proposed method the handling of alkaline HA solutions, the titration with very dilute NaOH or HCl solutions and the need for the availability of very small volumes of titrant to be added by microburettes may be avoided.

  18. Associations between plasma branched-chain amino acids, β-aminoisobutyric acid and body composition.

    PubMed

    Rietman, Annemarie; Stanley, Takara L; Clish, Clary; Mootha, Vamsi; Mensink, Marco; Grinspoon, Steven K; Makimura, Hideo

    2016-01-01

    Plasma branched-chain amino acids (BCAA) are elevated in obesity and associated with increased cardiometabolic risk. β-Aminoisobutyric acid (B-AIBA), a recently identified small molecule metabolite, is associated with decreased cardiometabolic risk. Therefore, we investigated the association of BCAA and B-AIBA with each other and with detailed body composition parameters, including abdominal visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT). A cross-sectional study was carried out with lean (n 15) and obese (n 33) men and women. Detailed metabolic evaluations, including measures of body composition, insulin sensitivity and plasma metabolomics were completed. Plasma BCAA were higher (1·6 (se 0·08) (×10(7)) v. 1·3 (se 0·06) (×10(7)) arbitrary units; P = 0·005) in obese v. lean subjects. BCAA were positively associated with VAT (R 0·49; P = 0·0006) and trended to an association with SAT (R 0·29; P = 0·052). The association between BCAA and VAT, but not SAT, remained significant after controlling for age, sex and race on multivariate modelling (P < 0·05). BCAA were also associated with parameters of insulin sensitivity (Matsuda index: R -0·50, P = 0·0004; glucose AUC: R 0·53, P < 0·001). BCAA were not associated with B-AIBA (R -0·04; P = 0·79). B-AIBA was negatively associated with SAT (R -0·37; P = 0·01) but only trended to an association with VAT (R 0·27; P = 0·07). However, neither relationship remained significant after multivariate modelling (P > 0·05). Plasma B-AIBA was associated with parameters of insulin sensitivity (Matsuda index R 0·36, P = 0·01; glucose AUC: R -0·30, P = 0·04). Plasma BCAA levels were positively correlated with VAT and markers of insulin resistance. The results suggest a possible complex role of adipose tissue in BCAA homeostasis and insulin resistance. PMID:27313851

  19. Biochemical composition of juvenile cultured vs. wild silver pomfret, Pampus argenteus: determining the diet for cultured fish.

    PubMed

    Zhao, Feng; Zhuang, Ping; Zhang, Longzhen; Shi, Zhaohong

    2010-12-01

    We evaluated the biochemical composition of juvenile cultured and wild silver pomfret Pampus argenteus. Cultured silver pomfret (SF) had significantly (P<0.05) lower crude protein content and higher crude lipid content than wild SF. Concentrations of almost all amino acids, except glycine and arginine, were significantly higher (P<0.05) in wild SF compared to cultured SF. Further, wild SF had a significantly (P<0.05) higher concentration of total amino acids (TAA), essential amino acids (EAA), and a higher essential amino acid index (EAAI) than cultured SF. Saturated fatty acids (SFA) in cultured SF were significantly higher than in wild SF. However, the content of poly-unsaturated fatty acids (PUFA) and n-3 fatty acids in wild SF was significantly higher than in cultured SF. Mono-unsaturated fatty acids (MUFA) in cultured and wild SF were not significantly different. Fatty acids C16:0 and C18:1 were the principal fatty acids of the SFAs and MUFAs, respectively, in both cultured and wild SF. The results will be useful for determining the dietary requirements for culture of SF.

  20. Use of hexadeuterated valproic acid and gas chromatography-mass spectrometry to determine the pharmacokinetics of valproic acid

    SciTech Connect

    Acheampong, A.A.; Abbott, F.S.; Orr, J.M.; Ferguson, S.M.; Burton, R.W.

    1984-04-01

    Di-(( 3,3,3-/sup 2/H3)propyl)acetic acid, a hexadeuterated analogue of valproic acid, was synthesized and its pharmacokinetic properties compared with valproic acid. Concentrations of valproic acid and (/sup 2/H)valproic acid in serum and saliva were determined by GC-MS using selected-ion monitoring. Saliva drug levels were measured with good precision down to 0.1 microgram/mL. Kinetic equivalence of valproic acid and (/sup 2/H)valproic acid was demonstrated in a single-dose study in a human volunteer. An isotope effect was observed for omega-oxidation, but the difference in metabolism was not sufficient to make (/sup 2/H)valproic acid biologically nonequivalent. The application of (/sup 2/H)valproic acid to determine the kinetics of valproic acid under steady-state concentrations was evaluated in the same volunteer. The kinetic data obtained with (/sup 2/H)valproic acid was consistent with previously reported values for valproic acid including kinetic differences observed between single-dose and steady-state experiments. Saliva levels of valproic acid were found to give a good correlation with total serum valproic acid under multiple-dose conditions. A concentration dependence was found for the ratio of saliva valproic acid to free valproic acid in serum, low ratios being observed at high serum concentrations of valproic acid.

  1. Determination and comparison of seed oil triacylglycerol composition of various soybeans (Glycine max (L.)) using ¹H-NMR spectroscopy.

    PubMed

    Kim, Won Woo; Rho, Ho Sik; Hong, Yong Deog; Yeom, Myung Hun; Shin, Song Seok; Yi, Jun Gon; Lee, Min-Seuk; Park, Hye Yoon; Cho, Dong Ha

    2013-11-21

    Seed oil triacylglycerol (TAG) composition of 32 soybean varieties were determined and compared using ¹H-NMR. The contents of linolenic (Ln), linoleic (L), and oleic (O) ranged from 10.7% to 19.3%, 37.4%-50.1%, and 15.7%-34.1%, respectively. As is evident, linoleic acid was the major fatty acid of soybean oil. Compositional differences among the varieties were observed. Natural oils containing unsaturated groups have been regarded as important nutrient and cosmetic ingredients because of their various biological activities. The TAG profiles of the soy bean oils could be useful for distinguishing the origin of seeds and controlling the quality of soybean oils. To the best of our knowledge, this is the first study in which the TAG composition of various soybean oils has been analyzed using the ¹H-NMR method.

  2. A novel poly(acrylic acid-co-acrylamide)/diatomite composite flocculant with outstanding flocculation performance.

    PubMed

    Xu, Kun; Liu, Yao; Wang, Yang; Tan, Ying; Liang, Xuecheng; Lu, Cuige; Wang, Haiwei; Liu, Xiusheng; Wang, Pixin

    2015-01-01

    Series of anionic flocculants with outstanding flocculation performance, poly(acrylic acid-co-acrylamide)/diatomite composite flocculants (PAAD) were successfully prepared through aqueous solution copolymerization and applied to flocculate from oil-field fracturing waste-water. The structure of PAAD was characterized by Fourier transform infra-red spectroscopy, (13)C nuclear magnetic resonance and X-ray diffraction tests, and its properties were systematically evaluated by viscometer, thermogravimetry analysis and flocculation measurements. Furthermore, the influences of various reaction parameters on the apparent viscosity of flocculant solution were studied, and the optimum synthesis condition was determined. The novel composite flocculants exhibited outstanding flocculation properties. Specifically, the dosage of composite flocculants that could make the transmittance of treated wastewater exceed 90% was only approximately 12-35 ppm, which was far lower than that of conventional flocculants. Meanwhile, the settling time was lower than 5 s, which was similar to that of conventional flocculants. This was because PAAD flocculants had a higher absorption capacity, and larger chain extending space than conventional linear flocculants, which could refrain from the entanglement of linear polymer chains and significantly improve flocculation capacity. PMID:26360748

  3. A novel poly(acrylic acid-co-acrylamide)/diatomite composite flocculant with outstanding flocculation performance.

    PubMed

    Xu, Kun; Liu, Yao; Wang, Yang; Tan, Ying; Liang, Xuecheng; Lu, Cuige; Wang, Haiwei; Liu, Xiusheng; Wang, Pixin

    2015-01-01

    Series of anionic flocculants with outstanding flocculation performance, poly(acrylic acid-co-acrylamide)/diatomite composite flocculants (PAAD) were successfully prepared through aqueous solution copolymerization and applied to flocculate from oil-field fracturing waste-water. The structure of PAAD was characterized by Fourier transform infra-red spectroscopy, (13)C nuclear magnetic resonance and X-ray diffraction tests, and its properties were systematically evaluated by viscometer, thermogravimetry analysis and flocculation measurements. Furthermore, the influences of various reaction parameters on the apparent viscosity of flocculant solution were studied, and the optimum synthesis condition was determined. The novel composite flocculants exhibited outstanding flocculation properties. Specifically, the dosage of composite flocculants that could make the transmittance of treated wastewater exceed 90% was only approximately 12-35 ppm, which was far lower than that of conventional flocculants. Meanwhile, the settling time was lower than 5 s, which was similar to that of conventional flocculants. This was because PAAD flocculants had a higher absorption capacity, and larger chain extending space than conventional linear flocculants, which could refrain from the entanglement of linear polymer chains and significantly improve flocculation capacity.

  4. Effects of sucking acidic candy on whole-mouth saliva composition.

    PubMed

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

    2005-01-01

    Limited information is available on the effects of sucking acidic candies on saliva composition and the protective role of saliva in this relation. Therefore the aim of this study was to determine salivary effects of sucking acidic candies in vivo in relation to individual variations in whole-saliva flow rate (WSFR) and buffer capacity (WSbeta). Ten healthy young males (24 +/- 2 years) sucked a rhubarb-flavoured acidic hard-boiled candy with tartaric acid available on the Danish market. The whole saliva was collected into a closed system, regarding CO2, at different times as follows: firstly, unstimulated saliva for 5 min (baseline), secondly stimulated saliva for 4 min upon sucking the candy, and finally post-stimulated saliva for 10 min. Saliva pH was determined on a blood gas analyser and WSbeta was estimated from the saliva bicarbonate concentration obtained by the analyser and by ionic balance calculation. The erosive potential of the candy in saliva was estimated from the saliva pH values and degree of saturation with respect to hydroxyapatite (DS(HAp)). The results showed that saliva pH dropped from 6.5 (baseline) down to 4.5 at the fourth minute of sucking the candy, and returned to pH 6.5 five minutes after stimulation (post-stimulated). DS(HAp) decreased upon sucking the candy and saliva from all subjects became undersaturated with respect to HAp. Significant positive correlations were obtained between pH and WSFR (r(s) = 0.47; p < 0.05) and between pH and WSbeta (r(s) = 0.65; p < 0.01). In relation to WSbeta we found that 70% of the buffer capacity originating from the bicarbonate buffer system upon sucking the candy was exerted as phase buffering. We conclude that sucking this type of acidic candies changes whole-mouth saliva composition so that it may have erosive potential and that high WSFR and WSbeta have protective effects against these salivary changes.

  5. 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...

  6. Influence of glyphosate on amino acid composition of Egyptian broomrape.

    PubMed

    Nandula, V K; Westwood, J H; Foster, J G; Foy, C L

    2001-03-01

    The parasitic plant broomrape is entirely dependent on its host for reduced carbon and nitrogen and is also susceptible to inhibition by glyphosate that is translocated to the parasite through a host. Studies were conducted to examine the effect of broomrape parasitism on amino acid concentrations of two hosts: common vetch that is tolerant of low levels of glyphosate and oilseed rape that has been genetically engineered for glyphosate resistance. The influence of glyphosate on the amino acid content of broomrape and the two hosts was also examined. Amino acid concentrations in leaves and roots of parasitized common vetch plants were generally similar to those of the corresponding tissues of nonparasitized plants. Amino acid concentrations in broomrape were lower than those of the parasitized common vetch root. For common vetch, glyphosate applied at rates that selectively inhibited broomrape growth did not alter individual amino acid concentrations in the leaves, but generally increased amino acid levels at 0.18 kg ha-1. Glyphosate application also increased the amino acid concentrations, with the exception of arginine, of broomrape growing on common vetch and did not generally influence concentrations in leaves or roots of common vetch. In oilseed rape, parasitization by broomrape generally led to higher amino acid concentrations in leaves but lower concentrations in roots of parasitized plants. Broomrape had higher amino acid concentrations than roots of the parasitized oilseed rape. Glyphosate applied at 0.25 and 0.5 kg ha-1 generally increased the amino acid concentrations in oilseed rape leaves, but the 0.75 kg ha-1 application caused the amino acid concentrations to decrease compared to those of untreated plants. In oilseed rape root the general trend was an increase in the concentration of amino acids at the two highest rates of glyphosate. Individual amino acid concentrations in broomrape attachments growing on oilseed rape were generally increased

  7. Fatty Acid Composition and Conjugated Linoleic Acid Content in Different Carcass parts of Dağlıç Lambs

    PubMed Central

    Karabacak, Ali; Boztepe, Saim

    2014-01-01

    This study was conducted to compare fatty acid composition and content of conjugated linoleic acid (CLA) in different regions of sheep carcasses. Lambs of the Dağlıç breed were used for this purpose. Subsequent to a 68-day period of intensive fattening, fatty acids were examined in samples taken from the legs, shoulders, breasts, and ribs of lamb carcasses. According to the analysis, in leg, shoulder, breast, and rib, respectively, total saturated fatty acids (SFA) were found to be 40.38, 42.69, 42.56, and 40.27%, unsaturated fatty acids (MUFA) were found to be 40.38, 44.17, 46.17, and 49.50%, polyunsaturated fatty acids (PUFA) were found to be 4.79, 4.29, 3.80, and 3.72%, and CLAs were found to be 1.49, 1.69, 1.53, and 1.59%. PMID:24523647

  8. Robustness of two-step acid hydrolysis procedure for composition analysis of poplar.

    PubMed

    Bhagia, Samarthya; Nunez, Angelica; Wyman, Charles E; Kumar, Rajeev

    2016-09-01

    The NREL standard procedure for lignocellulosic biomass composition has two steps: primary hydrolysis in 72% wt sulfuric acid at 30°C for 1h followed by secondary hydrolysis of the slurry in 4wt% acid at 121°C for 1h. Although pointed out in the NREL procedure, the impact of particle size on composition has never been shown. In addition, the effects of primary hydrolysis time and separation of solids prior to secondary hydrolysis on composition have never been shown. Using poplar, it was found that particle sizes less than 0.250mm significantly lowered the glucan content and increased the Klason lignin but did not affect xylan, acetate, or acid soluble lignin contents. Composition was unaffected for primary hydrolysis time between 30 and 90min. Moreover, separating solids prior to secondary hydrolysis had negligible effect on composition suggesting that lignin and polysaccharides are completely separated in the primary hydrolysis stage. PMID:27282557

  9. General analytical procedure for determination of acidity parameters of weak acids and bases.

    PubMed

    Pilarski, Bogusław; Kaliszan, Roman; Wyrzykowski, Dariusz; Młodzianowski, Janusz; Balińska, Agata

    2015-01-01

    The paper presents a new convenient, inexpensive, and reagent-saving general methodology for the determination of pK a values for components of the mixture of diverse chemical classes weak organic acids and bases in water solution, without the need to separate individual analytes. The data obtained from simple pH-metric microtitrations are numerically processed into reliable pK a values for each component of the mixture. Excellent agreement has been obtained between the determined pK a values and the reference literature data for compounds studied.

  10. Influence of aluminum-citrate and citric acid on tissue mineral composition in wether sheep.

    PubMed

    Allen, V G; Fontenot, J P; Rahnema, S H

    1991-02-01

    A 60-d trial was conducted to determine effects of A1-citrate and citric acid on tissue mineral composition in wether lambs. Eighteen crossbred, yearling wether lambs equipped with ruminal cannulas were fed a diet containing low (.12%) Mg and high (2.87%) K (DM basis) and were allotted to three treatments: 1) control; 2) 2,000 micrograms A1 as A1-citrate/g of diet DM and 3) citric acid equivalent to the citrate in treatment 2. Treatments were administered in 200 ml of deionized water twice daily in divided doses via ruminal cannula. At the end of 60 d, wethers were slaughtered and samples of rib and tibia bone, liver, kidney, brain, spleen, pancreas, parathyroid and pituitary gland were analyzed for mineral concentration. Concentrations of A1 increased (P less than .05) in rib, tibia, liver, kidney, spleen and pituitary gland and tended to increase in brain (P less than .13) in wethers treated with A1-citrate compared to citric acid. Magnesium was decreased in rib (P less than .01) and tended to be decreased in pituitary gland (P less than .15), whereas Ca tended to be decreased in pancreas (P less than .07), kidney (P less than .11) and parathyroid (P less than .10) by A1-citrate treatment compared to citric acid. Potassium decreased (P less than .01) in liver, Fe increased (P less than .05) in kidney, Zn decreased in pituitary (P less than .05) and tended to decrease in pancreas (P less than .10) due to A1-citrate but not citric acid.(ABSTRACT TRUNCATED AT 250 WORDS)

  11. Profiling serum bile acid glucuronides in humans: gender divergences, genetic determinants and response to fenofibrate

    PubMed Central

    Trottier, Jocelyn; Perreault, Martin; Rudkowska, Iwona; Levy, Cynthia; Dallaire-Theroux, Amélie; Verreault, Mélanie; Caron, Patrick; Staels, Bart; Vohl, Marie-Claude; Straka, Robert J.; Barbier, Olivier

    2014-01-01

    Glucuronidation, catalyzed by UDP-glucuronosyltransferase (UGT) enzymes detoxifies cholestatic bile acids (BAs). We aimed at i) characterizing the circulating BA-glucuronide (-G) pool composition in humans, ii) evaluating how sex and UGT polymorphisms influence this composition, and iii) analyzing the effects of lipid-lowering drug fenofibrate on the circulating BA-G profile in 300 volunteers and 5 cholestatic patients. Eleven BA-Gs were determined in pre- and post-fenofibrate samples. Men exhibited higher BA-G concentrations, and various genotype/BA-G associations were discovered in relevant UGT genes. The chenodeoxycholic acid-3G concentration was associated with the UGT2B7 802C>T polymorphism. Glucuronidation assays confirmed the predominant role of UGT2B7 and UGT1A4 in CDCA-3G formation. Fenofibrate exposure increased the serum levels of 5 BA-G species, including CDCA-3G, and up-regulated expression of UGT1A4, but not UGT2B7, in hepatic cells. This study demonstrates that fenofibrate stimulates BA glucuronidation in humans, and thus reduces bile acid toxicity in the liver. PMID:23756370

  12. Lipid complex effect on fatty acid profile and chemical composition of cow milk and cheese.

    PubMed

    Bodkowski, R; Czyż, K; Kupczyński, R; Patkowska-Sokoła, B; Nowakowski, P; Wiliczkiewicz, A

    2016-01-01

    The effect of administration of lipid complex (LC) on cow milk and cheese characteristics was studied. Lipid complex was elaborated based on grapeseed oil with synthesized conjugated linoleic acid (CLA) and Atlantic mackerel oil enriched in n-3 fatty acids. The 4-wk experiment was conducted on 30 Polish Holstein Friesian cows. The experimental group cow diet was supplemented with 400 g/d of LC (containing 38% CLA, and eicosapentaenoic acid + docosahexaenoic acid in a relative amount of 36.5%) on a humic-mineral carrier. The chemical composition and fatty acid profile of milk and rennet cheese from raw fresh milk were analyzed. Lipid complex supplementation of the total mixed ration had no effect on milk yield and milk composition, except fat content, which decreased from 4.6 to 4.1%, a 10.9% decrease. Milk from cows treated with LC had greater relative amounts of unsaturated fatty acids, particularly polyunsaturated fatty acids, and lesser relative amounts of saturated fatty acids. Lipid complex addition changed milk fat fatty acid profile: C18:2 cis-9,trans-11 and trans-10,cis-12 isomer (CLA) contents increased by 278 and 233%, respectively, as did eicosapentaenoic acid (C20:5) and docosahexaenoic acid (C22:6) contents. Milk fat fatty acid profile changes were correlated with the modifications in rennet cheese fatty acid profile. Lipid complex supplementation of dairy cows produced considerable changes in the biological value of milk and cheese fat.

  13. Lipid complex effect on fatty acid profile and chemical composition of cow milk and cheese.

    PubMed

    Bodkowski, R; Czyż, K; Kupczyński, R; Patkowska-Sokoła, B; Nowakowski, P; Wiliczkiewicz, A

    2016-01-01

    The effect of administration of lipid complex (LC) on cow milk and cheese characteristics was studied. Lipid complex was elaborated based on grapeseed oil with synthesized conjugated linoleic acid (CLA) and Atlantic mackerel oil enriched in n-3 fatty acids. The 4-wk experiment was conducted on 30 Polish Holstein Friesian cows. The experimental group cow diet was supplemented with 400 g/d of LC (containing 38% CLA, and eicosapentaenoic acid + docosahexaenoic acid in a relative amount of 36.5%) on a humic-mineral carrier. The chemical composition and fatty acid profile of milk and rennet cheese from raw fresh milk were analyzed. Lipid complex supplementation of the total mixed ration had no effect on milk yield and milk composition, except fat content, which decreased from 4.6 to 4.1%, a 10.9% decrease. Milk from cows treated with LC had greater relative amounts of unsaturated fatty acids, particularly polyunsaturated fatty acids, and lesser relative amounts of saturated fatty acids. Lipid complex addition changed milk fat fatty acid profile: C18:2 cis-9,trans-11 and trans-10,cis-12 isomer (CLA) contents increased by 278 and 233%, respectively, as did eicosapentaenoic acid (C20:5) and docosahexaenoic acid (C22:6) contents. Milk fat fatty acid profile changes were correlated with the modifications in rennet cheese fatty acid profile. Lipid complex supplementation of dairy cows produced considerable changes in the biological value of milk and cheese fat. PMID:26506539

  14. Dietary conjugated linoleic acids as free fatty acids and triacylglycerols similarly affect body composition and energy balance in mice.

    PubMed

    Terpstra, A H M; Javadi, M; Beynen, A C; Kocsis, S; Lankhorst, A E; Lemmens, A G; Mohede, I C M

    2003-10-01

    The objective of this study was to compare the effects of conjugated linoleic acid (CLA) as triacylglycerols (TAG) or free fatty acids (FFA) on body composition and energy balance in mice. We fed four groups of 5-wk-old Balb-C mice (n = 9) semipurified diets containing either CLA (0.5 g CLA/100 g of diet) or high oleic sunflower oil (HOSF) in the form of FFA or TAG for 42 d. Body composition was determined and the energy in the carcasses, excreta and food was measured in a bomb calorimeter. The amount of body fat was 4.72 +/- 0.95 g (17.9 +/- 2.8%) in the HOSF-FFA group, 2.36 +/- 0.29 g (9.4 +/- 1.0%) in the CLA-FFA mice (mean +/- SD, P < 0.05), 4.76 +/- 0.74 g (18.2 +/- 2.2%) in the HOSF-TAG group and 2.32 +/- 0.38 g (9.3 +/- 1.1%) in the CLA-TAG mice (P < 0.05). The percentage of energy intake that was stored in the body was 3.5 +/- 1.2% in the HOSF-FFA group, 0.6 +/- 0.3% in the CLA-FFA group (P < 0.05), 3.5 +/- 1.1% in the HOSF-TAG group and 0.5 +/- 0.4 in the CLA-TAG mice (P < 0.05). Conversely, the percentage of energy intake that was expended as heat was 89.4 +/- 1.2% in the HOSF-FFA group, 92.4 +/- 0.8% in the CLA-FFA mice (P < 0.05), 89.47 +/- 1.23% in the HOSF-TAG group and 92.2 +/- 0.4% in the CLA-TAG group (P < 0.05). Thus, CLA in the form of FFA or TAG had similar effects on body composition and energy balance.

  15. Dietary conjugated linoleic acids as free fatty acids and triacylglycerols similarly affect body composition and energy balance in mice.

    PubMed

    Terpstra, A H M; Javadi, M; Beynen, A C; Kocsis, S; Lankhorst, A E; Lemmens, A G; Mohede, I C M

    2003-10-01

    The objective of this study was to compare the effects of conjugated linoleic acid (CLA) as triacylglycerols (TAG) or free fatty acids (FFA) on body composition and energy balance in mice. We fed four groups of 5-wk-old Balb-C mice (n = 9) semipurified diets containing either CLA (0.5 g CLA/100 g of diet) or high oleic sunflower oil (HOSF) in the form of FFA or TAG for 42 d. Body composition was determined and the energy in the carcasses, excreta and food was measured in a bomb calorimeter. The amount of body fat was 4.72 +/- 0.95 g (17.9 +/- 2.8%) in the HOSF-FFA group, 2.36 +/- 0.29 g (9.4 +/- 1.0%) in the CLA-FFA mice (mean +/- SD, P < 0.05), 4.76 +/- 0.74 g (18.2 +/- 2.2%) in the HOSF-TAG group and 2.32 +/- 0.38 g (9.3 +/- 1.1%) in the CLA-TAG mice (P < 0.05). The percentage of energy intake that was stored in the body was 3.5 +/- 1.2% in the HOSF-FFA group, 0.6 +/- 0.3% in the CLA-FFA group (P < 0.05), 3.5 +/- 1.1% in the HOSF-TAG group and 0.5 +/- 0.4 in the CLA-TAG mice (P < 0.05). Conversely, the percentage of energy intake that was expended as heat was 89.4 +/- 1.2% in the HOSF-FFA group, 92.4 +/- 0.8% in the CLA-FFA mice (P < 0.05), 89.47 +/- 1.23% in the HOSF-TAG group and 92.2 +/- 0.4% in the CLA-TAG group (P < 0.05). Thus, CLA in the form of FFA or TAG had similar effects on body composition and energy balance. PMID:14519807

  16. Fatty acid compositions of triglycerides and free fatty acids in sebum depend on amount of triglycerides, and do not differ in presence or absence of acne vulgaris.

    PubMed

    Akaza, Narifumi; Akamatsu, Hirohiko; Numata, Shigeki; Matsusue, Miyuki; Mashima, Yasuo; Miyawaki, Masaaki; Yamada, Shunji; Yagami, Akiko; Nakata, Satoru; Matsunaga, Kayoko

    2014-12-01

    To clarify the influence of the fatty acid composition of sebum in acne vulgaris, we investigated the amounts and fatty acid compositions of triglycerides (TG) and free fatty acids (FFA), and the amounts of cutaneous superficial Propionibacterium acnes in acne patients and healthy subjects. The foreheads of 18 female patients, 10 male patients, 10 healthy females and 10 healthy males were studied in a Japanese population. There were significant differences in the amounts of sebum, TG and cutaneous superficial P. acnes, as well as the fatty acid compositions of TG and FFA between acne patients and healthy subjects in females. Their fatty acid compositions were correlated with the amount of TG with or without acne. It was clarified that the fatty acid compositions of TG and FFA depended on the amount of TG, and there were no differences in the fatty acid composition in the presence and absence of acne.

  17. New estimation method for fatty acid composition in oil using near infrared spectroscopy.

    PubMed

    Sato, Tetsuo

    2002-12-01

    The absorption bands of cis-unsaturation and the carbon chain length of the fatty acid moieties in oil appear in the near infrared (NIR) wavelength region, especially around 1600-1800 nm. Using this region, a new estimation method for fatty acid composition analysis is proposed. Because the differences of the original NIR spectra are miniscule even in this region, the second derivative NIR spectra were examined in order to estimate the fatty acid composition in oil exclusively from the spectral patterns obtained. The parameters for calculating the second derivative NIR spectra were examined to make the spectral difference clearer. In any parameter, the absorption band was shifted to the shorter wavelength region when the unsaturation in fatty acid moieties increased, and it was shifted to the longer wavelength region when the carbon chain length increased. When the parameters were correct, this NIR method can estimate the fatty acid composition roughly, but simply, easily, and sometimes nondestructively.

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

    SciTech Connect

    Lambert, R.M.

    1989-01-01

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

  19. Evaluating and predicting the oxidative stability of vegetable oils with different fatty acid compositions.

    PubMed

    Li, Hongyan; Fan, Ya-wei; Li, Jing; Tang, Liang; Hu, Jiang-ning; Deng, Ze-yuan

    2013-04-01

    The aim of this research was to evaluate the oxidative stabilities and qualities of different vegetable oils (almond, blend 1-8, camellia, corn, palm, peanut, rapeseed, sesame, soybean, sunflower, and zanthoxylum oil) based on peroxide value (PV), vitamin E content, free fatty acid, and fatty acid composition. The vegetable oils with different initial fatty acid compositions were studied under accelerated oxidation condition. It showed that PV and n-3 polyunsaturated fatty acid (PUFA) changed significantly during 21 d accelerated oxidation storage. Based on the changes of PV and fatty acid composition during the oxidation process, mathematical models were hypothesized and the models were simulated by Matlab to generate the proposed equations. These equations were established on the basis of the different PUFA contents as 10% to 28%, 28% to 46%, and 46% to 64%, respectively. The simulated models were proven to be validated and valuable for assessing the degree of oxidation and predicting the shelf life of vegetable oils.

  20. [FATTY ACID COMPOSITION ALTEROMONAS-LIKE BACTERIA ISOLATED FROM THE BLACK SEA WATER].

    PubMed

    Klochko, V V; Avdeeva, L V

    2015-01-01

    Alteromonas macleodii strains isolated from the Black sea water were similar in their fatty acids composition with the type strain of this species. Analysis of lipid composition of 10 A. macleodii strains isolated from the deep and surface water layers in different World ocean regions including the Black sea water has shown that the deep and surface isolates of this species formed two groups different in their fatty acids profiles. The Black sea isolates of Pseudoalteromonas haloplanktis, P. citrea, P. flavipulchra conformed to these species type strains in their fatty acids composition. On the basis of the fatty acids spectra similarity of three Pseudoalteromonas species strains with Plipolytica described in 2010 has been established. Presence of three isomers C16:1ψ7, C 16:1ψ9 and C16:1ψ6--components of hexadecenic acid in the Black sea isolates of Shewanella baltica has been shown. PMID:26638484

  1. Quantitative Determination of Fatty Acids in Marine Fish and Shellfish from Warm Water of Straits of Malacca for Nutraceutical Purposes

    PubMed Central

    Abd Aziz, Nurnadia; Azlan, Azrina; Ismail, Amin; Mohd Alinafiah, Suryati; Razman, Muhammad Rizal

    2013-01-01

    This study was conducted to quantitatively determine the fatty acid contents of 20 species of marine fish and four species of shellfish from Straits of Malacca. Most samples contained fairly high amounts of polyunsaturated fatty acids (PUFAs), especially alpha-linolenic acid (ALA, C18:3 n3), eicosapentaenoic acid (EPA, C20:5 n3), and docosahexaenoic acid (DHA, C22:6 n3). Longtail shad, yellowstripe scad, and moonfish contained significantly higher (P < 0.05) amounts of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and alpha-linolenic acid (ALA), respectively. Meanwhile, fringescale sardinella, malabar red snapper, black pomfret, Japanese threadfin bream, giant seaperch, and sixbar grouper showed considerably high content (537.2–944.1 mg/100g wet sample) of desirable omega-3 fatty acids. The polyunsaturated-fatty-acids/saturated-fatty-acids (P/S) ratios for most samples were higher than that of Menhaden oil (P/S = 0.58), a recommended PUFA supplement which may help to lower blood pressure. Yellowstripe scad (highest DHA, ω − 3/ω − 6 = 6.4, P/S = 1.7), moonfish (highest ALA, ω − 3/ω − 6 = 1.9, P/S = 1.0), and longtail shad (highest EPA, ω − 3/ω − 6 = 0.8, P/S = 0.4) were the samples with an outstandingly desirable overall composition of fatty acids. Overall, the marine fish and shellfish from the area contained good composition of fatty acids which offer health benefits and may be used for nutraceutical purposes in the future. PMID:23509703

  2. Fatty acid composition of brown adipose tissue in genetically heat-tolerant FOK rats

    NASA Astrophysics Data System (ADS)

    Ohno, T.; Furuyama, F.; Kuroshima, A.

    The phospholipid fatty acid composition of brown adipose tissue (BAT) was examined in inbred heat-tolerant FOK rats and compared with that in conventional Wistar rats not previously exposed to heat. The FOK rats showed higher unsaturation states, as indicated by higher levels of polyunsaturated fatty acids and a higher unsaturation index and polyunsaturated fatty acids/saturated fatty acids ratio. This higher level of unsaturation was characterized by the higher amount of polyunsaturated fatty acids such as linoleic acid, arachidonic acid and docosahexaenoic acid. It may be concluded that the increased docosahexaenoic acid level in BAT phospholipids brings about the hyperplasia of BAT, causing an enhancement of its in vivo thermogernic activity as well as the systemic non-shivering thermogenesis observed in heat-tolerant FOK rats.

  3. How Diagenesis Determines the Deep Ocean's ɛNd Composition

    NASA Astrophysics Data System (ADS)

    Abbott, A. N.; Haley, B. A.; McManus, J.

    2015-12-01

    We measured the Nd isotope composition (ɛNd) of the water column, sedimentary pore fluids, and sediment leaches of cores from a transect through the oxygen deficient zone of the northeast Pacific. Our results imply that pore fluids represent the dominant supply term for Nd to seawater. Based on a suite of analysis including rare earth element concentrations and ɛNd, we predict that the difference in grain size between the bulk sediment (pre leach) and the refractory particulates (post leach) is a key variable in determining the magnitude of the source of Nd to seawater, and that both the refractory phase (~20%) and labile phase (~80%) contribute to the pore fluid Nd concentrations during diagenesis. Our results suggest that pore fluid ɛNd ultimately determines the ɛNd of the labile phase because the labile phase appears to be formed during early diagenesis. The implication of our work is that the ɛNd recorded in the labile coatings, which is often utilized as a proxy for past seawater ɛNd, is not a bottom water signature. Instead, similarities between labile ɛNd and bottom water ɛNd occur where the pore fluid ɛNd controls both the bottom water ɛNd as well as the labile ɛNd, thus producing the apparent utility of the coatings as a seawater archive. Therefore, the labile ɛNd and bottom water ɛNd will be similar in regions with a large benthic flux. We suggest that this improved understanding of the factors influencing ɛNd as a tracer will make reconstructions more precise.

  4. Determining the chemical composition of cloud condensation nuclei

    SciTech Connect

    Williams, A.L.; Rothert, J.E.; McClure, K.E. ); Alofs, D.J.; Hagen, D.E.; Schmitt, J.; White, D.R.; Hopkins, A.R.; Trueblood, M.B. . Cloud and Aerosol Science Lab.)

    1992-12-01

    This third progress report describes the status of our efforts to develop the instrumentation to collect cloud condensation nuclei (CCN) in amounts sufficient for chemical analysis. During the fall of 1992 we started collecting filter samples of CCN with the laboratory version of the apparatus at Rolla -MO. The mobile version of the apparatus is in the latter stages of construction. This report includes a fairly rigorous discussion of the operation of the CCN sampling system. A statistical model of the operation of the system is presented to show the ability of the system to collect CCN in the two different size ranges for which we plan to determine the chemical composition. A question is raised by the model results about the operation of one of the virtual impactors. It appears to pass a small percent of particles larger than its cut-point that has the potential of contaminating the smallest CCN sample with larger CCN material. Further tests are necessary, but it may be necessary to redesign that impactor. The appendices of the report show pictures of both the laboratory version and the mobile version of the CCN sampling system. The major hardware has been completed, and the mobile version will be in operation within a few weeks.

  5. Analysis of total oil and fatty acids composition by near infrared reflectance spectroscopy in edible nuts

    NASA Astrophysics Data System (ADS)

    Kandala, Chari V.; Sundaram, Jaya

    2014-10-01

    Near Infrared (NIR) Reflectance spectroscopy has established itself as an important tool in quantifying water and oil present in various food materials. It is rapid and nondestructive, easier to use, and does not require processing the samples with corrosive chemicals that would render them non-edible. Earlier, the samples had to be ground into powder form before making any measurements. With the development of new soft ware packages, NIR techniques could now be used in the analysis of intact grain and nuts. While most of the commercial instruments presently available work well with small grain size materials such as wheat and corn, the method present here is suitable for large kernel size products such as shelled or in-shell peanuts. Absorbance spectra were collected from 400 nm to 2500 nm using a NIR instrument. Average values of total oil contents (TOC) of peanut samples were determined by standard extraction methods, and fatty acids were determined using gas chromatography. Partial least square (PLS) analysis was performed on the calibration set of absorption spectra, and models were developed for prediction of total oil and fatty acids. The best model was selected based on the coefficient of determination (R2), Standard error of prediction (SEP) and residual percent deviation (RPD) values. Peanut samples analyzed showed RPD values greater than 5.0 for both absorbance and reflectance models and thus could be used for quality control and analysis. Ability to rapidly and nondestructively measure the TOC, and analyze the fatty acid composition, will be immensely useful in peanut varietal improvement as well as in the grading process of grain and nuts.

  6. Effect of different levels of supplied cobalt on the fatty acid composition of bovine milk.

    PubMed

    Karlengen, Inger J; Taugbøl, Ole; Salbu, Brit; Aastveit, Are H; Harstad, Odd M

    2013-03-14

    In previous studies, administration of high amounts of Co decreased the proportion of MUFA in bovine milk. The present study was conducted to examine the amount of Co needed to obtain this effect. High-yielding dairy cows (n 4), equipped with ruminal cannulas, were used in a 4 × 4 Latin square design study. The basal diet consisted of concentrate mixture (9 kg/d) without added Co and grass silage (ad libitum). The following four levels of Co were administrated as cobalt acetate dissolved in distilled water: no Co (treatment 1, T1); 4·0 mg Co/d (T2); 380 mg Co/d (T3); 5300 mg Co/d (T4). Each period lasted for 18 d, including 11 d of treatment. During the treatment periods, the solutions were continuously infused into the rumen. Milk yield and milk concentration of fat, fatty acids (FA), protein, lactose, Co, Zn, Fe and Cu were determined. Blood plasma was analysed with respect to FA, Co, Zn, Fe and Cu. Feed intake and total tract digestibility of feed components were also determined. There was a linear effect of increasing the level of Co on milk FA composition. The effects of Co on FA composition in blood were insignificant compared with the effects on milk. In milk fat, the concentration of cis-9-18 : 1 was reduced by as much as 38 % on T4 compared with T1. Feed intake and milk yield were negatively affected by increasing the Co level.

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

    NASA Technical Reports Server (NTRS)

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

    2012-01-01

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

  8. Experimental determination of the effects of moisture on composite-to-composite adhesive joints

    NASA Technical Reports Server (NTRS)

    Deiasi, R. J.; Schulte, R. L.

    1981-01-01

    The primary mode of moisture ingress into bonded composite joints is determined using a nuclear probe for deuterium (NPD) to measure the localized D2O content along the length of the adhesive (FM-300 and EA-9601) and through the thickness of bonded composite speciments. Calculated diffusivities and NPD measured equilibrium moisture contents are used to predict the moisture profiles along the length of the adhesives as a function of exposure time, temperature, and relative humidity. These results are compared with the observed moisture profiles to evaluate the extent of enhanced edge diffusion. The FM-300 adhesive exhibits good agreement between measured and predicted profiles at 49 C, 70% and 90% RH, and 77 C, 70% RH. At 77 C, 90% RH, the measured moisture content near the adhesive edge is substantially larger than the predicted level. The EA-9601 adhesive also shows good agreement at 49 C, 70% and 90% RH, but at 77 C, the concentration of D20 near the edges is enhanced at each humidity level. The effect of moisture content on the bond shear strength at room temperature and at elevated temperature is evaluated.

  9. [Fatty acid composition variability of rapeseed oil: classical selection and biotechnology].

    PubMed

    Sakhno, L A

    2010-01-01

    The problems and achievements in the rapeseed Brassica napus L. var. oleifera breeding directed on the change of fatty acid composition in seed oil with the use of traditional and genetic engineering approaches are analyzed. It is noticed that the combination of biotechnological workings out and methods of classical breeding is the optimum for the further improvement of rapeseed oil composition.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  11. Effects of feeding omega-3-fatty acids on fatty acid composition and quality of bovine sperm and on antioxidative capacity of bovine seminal plasma.

    PubMed

    Gürler, Hakan; Calisici, Oguz; Calisici, Duygu; Bollwein, Heinrich

    2015-09-01

    The aim of the present study was to examine the effects of feeding alpha-linolenic (ALA) acid on fatty acid composition and quality of bovine sperm and on antioxidative capacity of seminal plasma. Nine bulls (ALA bulls) were fed with 800 g rumen-resistant linseed oil with a content of 50% linolenic acid and eight bulls with 400 g palmitic acid (PA bulls). Sperm quality was evaluated for plasma membrane and acrosome intact sperm (PMAI), the amount of membrane lipid peroxidation (LPO), and the percentage of sperm with a high DNA fragmentation index (DFI). Fatty acid content of sperm was determined using gas chromatography. Total antioxidant capacity, glutathione peroxidase, and superoxide dismutase activity were determined in seminal plasma. Feeding ALA increased (P < 0.05) the docosahexaenoic acid (DHA) content in bulls whereas in PA bulls did not change. PMAI increased after cryopreservation in ALA bulls as well as in PA bulls during the experiment period (P < 0.005). LPO of sperm directly after thawing did not change during the study period in ALA group, but decreased in PA group (P < 0.006). After 3h of incubation LPO increased in the ALA group (P < 0.02), while LPO did not differ between phases within groups. In conclusion, feeding of neither saturated nor polyunsaturated fatty acids affect the antioxidant levels in seminal plasma. Both saturated as well as polyunsaturated fatty acids had positive effects on quality of cryopreserved bovine sperm, although the content of docosahexaenoic acid in sperm membranes increased only in ALA bulls.

  12. Seasonal variations of the composition of microbial biofilms in sandy tidal flats: Focus of fatty acids, pigments and exopolymers

    NASA Astrophysics Data System (ADS)

    Passarelli, Claire; Meziane, Tarik; Thiney, Najet; Boeuf, Dominique; Jesus, Bruno; Ruivo, Mickael; Jeanthon, Christian; Hubas, Cédric

    2015-02-01

    Biofilms, or microbial mats, are common associations of microorganisms in tidal flats; they generally consist of a large diversity of organisms embedded in a matrix of Extracellular Polymeric Substances (EPS). These molecules are mainly composed of carbohydrates and proteins, but their detailed monomer compositions and seasonal variations are currently unknown. Yet this composition determines the numerous roles of biofilms in these systems. This study investigated the changes in composition of carbohydrates in intertidal microbial mats over a year to decipher seasonal variations in biofilms and in varying hydrodynamic conditions. This work also aimed to assess how these compositions are related to microbial assemblages. In this context, natural biofilms whose development was influenced or not by artificial structures mimicking polychaete tubes were sampled monthly for over a year in intertidal flats of the Chausey archipelago. Biofilms were compared through the analysis of their fatty acid and pigment contents, and the monosaccharide composition of their EPS carbohydrates. Carbohydrates from both colloidal and bound EPS contained mainly glucose and, to a lower extent, galactose and mannose but they showed significant differences in their detailed monosaccharide compositions. These two fractions displayed different seasonal evolution, even if glucose accumulated in both fractions in summer; bound EPS only were affected by artificial biogenic structures. Sediment composition in fatty acids and pigments showed that microbial communities were dominated by diatoms and heterotrophic bacteria. Their relative proportions, as well as those of other groups like cryptophytes, changed between times and treatments. The changes in EPS composition were not fully explained by modifications of microbial assemblages but also depended on the processes taking place in sediments and on environmental conditions. These variations of EPS compositions are likely to alter different

  13. Comparative evaluation of essential fatty acid composition of mothers' milk of some urban and suburban regions of West Bengal, India.

    PubMed

    Roy, Susmita; Dhar, Pubali; Ghosh, Santinath

    2012-12-01

    This study investigated the fatty acid composition of lipid present in breast milk of mothers residing in urban and suburban regions of West Bengal with special emphasis on n-6 and n-3 polyunsaturated fatty acids, which played a crucial role in the growth and development of neonates. Milk samples collected from 135 mothers of middle income group (average monthly income around 'Rs 10,000/-') were analysed by gas liquid chromatography after extraction and transmethylation to determine fatty acid composition. Information about the dietary intake of individual mothers was obtained through food frequency questionnaire. The fractions of n-6 and n-3 polyunsaturated fatty acids available in milk of urban mothers were 13.59 ± 0.94 and 3.65 ± 0.49, respectively, and in suburban mothers 12.74 ± 0.89 and 4.36 ± 0.39, respectively. The green leafy vegetables, fishes and vegetable oils were the major sources of essential fatty acids in the diet of the experimental groups of Bengali mothers. This study revealed a relationship between the alimentary habits of mothers and the concentration of essential fatty acids in breast milk of Bengali mothers.

  14. The effect of sire breed on the melting point and fatty acid composition of subcutaneous fat in steers.

    PubMed

    Perry, D; Nicholls, P J; Thompson, J M

    1998-01-01

    Fatty acid composition and the melting point of subcutaneous fat was determined in 18 Hereford, 25 Brahman x Hereford, 22 Simmental x Hereford, and 15 Friesian x Hereford steers that were grown out on pasture at two sites and slaughtered when the mean weight of the Herefords at each site was ca. 450 kg. Multivariate and univariate analyses tested the relations of fatty acid composition, degree of saturation, and melting point with sire breed, environment, age, and carcass characteristics. Hereford and Brahman steers were fatter than the Simmental and Friesian steers. Fat from Brahman-sired steers had a melting point 2.5 degrees C lower than fat from the Bos taurus-sired steers at the same age and had a higher proportion of unsaturated fatty acids, independent of variation in carcass weight and fatness. Melting point and degree of saturation decreased as age increased. Step-down discriminant analyses identified a set of three acids (14:0, 16:0, and 17:1) that differed among sire breeds, independent of differences in melting point: the acids 14:0 and 16:0 discriminated between Brahman and Bos taurus steers and 17:1 between Hereford and Simmental and Friesian steers. Increase in fatness was associated with an increase in 17:1, but, at the same fatness, no acids discriminated among the Bos taurus-sired steers. The use of Bos indicus cattle or their crossbreeds in situations in which hard-setting fat is likely may mitigate the problem.

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

    NASA Technical Reports Server (NTRS)

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

    2005-01-01

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

  16. Effects of alcohol inhalation on the fatty acid composition of rat tissues

    SciTech Connect

    Melville, D.M.; Karanian, J.W.; Salem, N. Jr.

    1986-05-01

    The objective of this study was to determine if polyunsaturated fatty acid levels in rat tissues are altered by alcohol exposure. Therefore, rats were exposed to ethanol vapor using an inhalation system designed in their laboratory and capable of producing rats with blood ethanol concentrations (BEC) of 50-400 mg%, as desired. Mean BEC were determined after 7 or 14 days of exposure and the lipids were extracted from brains, hearts, livers and aortas by the method of Bligh and Dyer. These total lipid extracts were transmethylated with BF/sub 3/ in methanol and analyzed using a fused silica capillary column. The largest compositional changes were observed in the liver after 14 days of exposure; 18:0, 18:2w6 and 20:4w6 decreased by 7, 18, and 20%, respectively, whereas 16:1w7, 18:1w9, 18:3w3 and 22:6w3 increased by 42, 19, 9, and 11%, respectively. A similar, although quantitatively smaller, effect was observed after only 7 days of alcohol inhalation. Little change was observed in the total lipid extract fatty acyl distribution in the brain or heart, however, the aorta showed losses in the polyunsaturates 20:4w6 and 22:6w3. More detailed data will be presented for the fatty acid distributional changes in individual phospholipid classes. It appears that the direction and magnitude of compositional changes depend upon both the duration of exposure and the blood concentration of alcohol.

  17. Application of peanut butter to improve fatty acid composition of biscuits.

    PubMed

    Gajera, H P; Kapopara, M B; Patel, V H

    2010-06-01

    Biscuits prepared with different levels of hydrogenated fat (vanaspati) and peanut (Arachis hypogaea L.) butter (PB) (100:00, 75:25, 50;50, 25;75, 00:100) were evaluated for their fatty acid composition and textural property. Saturated fatty acids like myristic, palmitic, stearic acids were higher in control biscuits (100% vanaspati), which decreased with increasing proportion of PB in the experimental biscuits. Oleic acid and linoleic acid were lowest in control biscuits and it gradually increased upon incorporation of PB. The hardness of biscuits also increased with increasing proportion of PB. Overall sensory quality of experimental biscuits improved when 50% vanaspati replaced by PB in the standard biscuits recipe. Biscuits prepared with 50% supplementation of PB had better fatty acid composition with balanced oil quality and also had a greater acceptability by sensory evaluation panel.

  18. Analysis of fatty acid composition of sea cucumber Apostichopus japonicus using multivariate statistics

    NASA Astrophysics Data System (ADS)

    Xu, Qinzeng; Gao, Fei; Xu, Qiang; Yang, Hongsheng

    2014-11-01

    Fatty acids (FAs) provide energy and also can be used to trace trophic relationships among organisms. Sea cucumber Apostichopus japonicus goes into a state of aestivation during warm summer months. We examined fatty acid profiles in aestivated and non-aestivated A. japonicus using multivariate analyses (PERMANOVA, MDS, ANOSIM, and SIMPER). The results indicate that the fatty acid profiles of aestivated and non-aestivated sea cucumbers differed significantly. The FAs that were produced by bacteria and brown kelp contributed the most to the differences in the fatty acid composition of aestivated and nonaestivated sea cucumbers. Aestivated sea cucumbers may synthesize FAs from heterotrophic bacteria during early aestivation, and long chain FAs such as eicosapentaenoic (EPA) and docosahexaenoic acid (DHA) that produced from intestinal degradation, are digested during deep aestivation. Specific changes in the fatty acid composition of A. japonicus during aestivation needs more detailed study in the future.

  19. A citric acid-based hydroxyapatite composite for orthopedic implants.

    PubMed

    Qiu, Hongjin; Yang, Jian; Kodali, Pradeep; Koh, Jason; Ameer, Guillermo A

    2006-12-01

    We describe a novel approach to process bioceramic microparticles and poly(diol citrates) into bioceramic-elastomer composites for potential use in orthopedic surgery. The composite consists of the biodegradable elastomer poly(1,8-octanediol-citrate) (POC) and the bioceramic hydroxyapatite (HA). The objective of this work was to characterize POC-HA composites and assess the feasibility of fabricating tissue fixation devices using machining and molding techniques. The mechanical properties of POC-HA composites with HA (40, 50, 60, 65wt.%) were within the range of values reported for tissue fixation devices (for POC-HA 65wt.%, S(b)=41.4+/-3.1, E(b)=501.7+/-40.3, S(c)=74.6+/-9.0, E(c)=448.8+/-27.0, S(t)=9.7+/-2.3, E(t)=334.8+/-73.5, S(s)=27.7+/-2.4, T(s)=27.3+/-4.9, all values in MPa). At 20 weeks, the weight loss of POC-HA composites ranged between 8 and 12wt.%, with 65wt.% HA composites degrading the slowest. Exposure of POC-HA to simulated body fluid resulted in extensive mineralization in the form of calcium phosphate with Ca/P of 1.5-1.7 similar to bone. POC-HA supported osteoblast adhesion in vitro and histology results from POC-HA samples that were implanted in rabbit knees for 6 weeks suggest that the composite is biocompatible. Synthesis of POC-HA is easy and inexpensive, does not involve harsh solvents or initiators, and the mechanical properties of POC-HA with 65wt.% HA are suitable for the fabrication of potentially osteoconductive bone screws.

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

    PubMed

    Agren, J J; Törmälä, M L; Nenonen, M T; Hänninen, O O

    1995-04-01

    The fatty acid composition of erythrocytes, platelets, and serum lipids was compared between subjects who had been eating a strict uncooked vegan diet ("living food") for years and omnivore controls. The vegan diet contains equal amounts of fat but more monounsaturated and polyunsaturated and less saturated fatty acids than the mixed diet of the control group. In vegans, the proportion of linoleic acid was greater in all lipid fractions studied. Also, the levels of other n-6 fatty acids were greater, with the exception of arachidonic acid levels, which were similar in most fractions. In erythrocytes, platelets and serum phospholipid fractions, this increase was mainly at the expense of the n-3 fatty acids. The proportions of eicosapentaenoic and docosahexaenoic acid were only 29-36% and 49-52% of those in controls, respectively. In vegans the ratio of n-3 to n-6 fatty acids was only about half that in omnivores. In addition to the lower levels of n-3 fatty acids, the proportions of palmitic and stearic acids were lower in serum cholesteryl esters, triglycerides and free fatty acids of vegans. The proportion of oleic acid was slightly lower only in serum cholesteryl esters and erythrocyte phosphatidylserine. The results show that, in the long term, the vegan diet has little effect on the proportions of oleic and arachidonic acids, whereas the levels of n-3 fatty acids are depressed to very low levels with prolonged consumption of the high linoleic and oleic acid components of this diet.

  1. [Determination of docosahexaenoic acid in milk powder by gas chromatography using acid hydrolysis].

    PubMed

    Shao, Shiping; Xiang, Dapeng; Li, Shuang; Xi, Xinglin; Chen, Wenrui

    2015-11-01

    A method to determine docosahexenoic acid (DHA) in milk powder by gas chromatography was established. The milk powder samples were hydrolyzed with hydrochloric acid, extracted to get total fatty acids by Soxhlet extractor, then esterified with potassium hydroxide methanol solution to form methyl esters, and treated with sodium hydrogen sulfate. The optimal experiment conditions were obtained from orthogonal experiment L9(3(3)) which performed with three factors and three levels, and it requires the reaction performed with 1 mol/L potassium hydroxide solution at 25 degrees C for 5 min. The derivative treated with sodium hydrogen sulfate was separated on a column of SP-2560 (100 m x 0.25 mm x 0.20 μm), and determined in 55 min by temperature programming-gas chromatography. Good linearity was obtained in the range 5.0-300 mg/L with the correlation coefficient of 0.999 9. The relative standard deviations (RSDs) were 3.4%, 1.2% and 1.1% for the seven repeated experiments of 10, 50 and 100 mg/L of DHA, respectively. The limit of detection was 2 mg/kg, and the recoveries of DHA were in the range of 90.4%-93.5%. The results are satisfactory through the tests of practical samples. PMID:26939370

  2. Determination of free fatty acids in beer wort.

    PubMed

    Bravi, Elisabetta; Benedetti, Paolo; Marconi, Ombretta; Perretti, Giuseppe

    2014-05-15

    The importance of free fatty acids (FFAs) in wort has been known for a long time because of their influence on beer quality and yeast metabolism. Lipids have a beneficial effect on yeast growth during fermentation as well as negative effects on beer quality. Lipids content of beer affects the ability to form a stable head of foam and plays an important role in beer staling. Moreover, the ratio of unsaturated and saturated fatty acids seems to be related to gushing problems. A novel, simple, and reliable procedure for quantitative analysis of FFAs in wort was developed and validated. The determination of FFAs in wort was achieved via liquid-liquid cartridge extraction, purification of FFA fraction by solid phase extraction, boron trifluoride in methanol methylation, and injection into GC-FID system. The proposed method has high accuracy (<0.3%, expressed as the bias), high precision (<1.2%, RSD), and recoveries ranging from 74% to 98%. The method was tested on two different wort samples (9° and 12° Plato).

  3. Fatty acid composition and egg components of specialty eggs.

    PubMed

    Cherian, G; Holsonbake, T B; Goeger, M P

    2002-01-01

    Egg components, total fat, and fatty acid content of specialty eggs were compared. One dozen eggs were collected and analyzed from each of five different brands from hens fed a diet free of animal fat (SP1), certified organic free-range brown eggs (SP2), uncaged unmedicated brown eggs (SP3), cage-free vegetarian diet brown eggs (SP4), or naturally nested uncaged (SP5). Regular white-shelled eggs were the control. A significant (P < 0.05) difference was observed in the egg components and fatty acid content in different brands. The percentage of yolk was lower (P < 0.05) in SP2 and SP4 with a concomitant increase (P < 0.05) in the percentage of white. The percentage of shell was lower (P < 0.05) in SP4 and SP5. The total edible portion was greater in SP4 and SP5. The yolk:white ratio was greater (P < 0.05) in SP3. The total lipid content was lower in SP4 eggs. The content of palmitic (C16:0), stearic (C18:0), and total saturated fatty acids were lower (P < 0.05) in SP1. No difference was observed in the content of palmitoleic (C16:1), oleic (C18:1), or total monounsaturated fatty acids. The content of n-3 fatty acids in SP2, SP4, and SP5 were similar to control eggs. The ratio of total n-6:n-3 polyunsaturated fatty acids ranged from 39.2 for SP5 to 11.5 for SP1 (P < 0.05). No difference was observed in the total polyunsaturated fatty acid content of eggs (P > 0.05).

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

    PubMed

    Periche, Angela; Koutsidis, Georgios; Escriche, Isabel

    2014-03-01

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

  5. Compositions containing amino acids, phosphate and manganese and their uses

    DOEpatents

    Daly, Michael J.; Gaidamakova, Elena K.

    2016-01-12

    The invention provides methods of producing vaccines directed against microorganisms, with the methods comprising culturing, harvesting and/or suspending the microorganism in the presence of a radiation-protective composition and irradiating the bacteria or viruses with a dose of radiation sufficient to render the microorganism replication-deficient and/or non-infective. The radiation-protective compositions used in the methods of the present invention comprise at least one nucleoside, at least one antioxidant and at least one small peptide. The invention also provides methods of rendering bacteria in culture resistant to ionizing radiation (IR), with these methods comprising culturing the bacteria in the presence of a radiation-protective composition.

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

    PubMed Central

    2011-01-01

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

  7. Antioxidant capacity and fatty acid composition of different parts of Adenocarpus complicatus (Fabaceae) from Turkey.

    PubMed

    Berber, Adnan; Zengin, Gokhan; Aktumsek, Abdurrahman; Sanda, Murad Aydin; Uysal, Tuna

    2014-03-01

    Adenocarpus complicatus is distributed throughout the Anatolian peninsula and is widely used for human and animal nutrition. The purpose of this work was to study the antioxidant properties and fatty acid composition of different parts of this plant (fruits and mixed materials). The species was collected from Golyuzu village of the Seydisehir district near Konya province, Turkey. Fruit and mixed parts obtained from this species were ground and a 15g sample was used to prepare methanolic extracts. Powdered plant samples were extracted with 100mL methanol in a mechanical shaker. The obtained extracts were filtered and concentrated to dryness under reduced pressure and were subsequently stored at -20 degrees C. Antioxidant components, namely total phenolic and flavonoid content, were detected for each extract using spectrophotometric methods. Antioxidant capacity was evaluated by various assays including phosphomolybdenum, DPPH free radical scavenging capacity, metal chelating activity, and ferric and cupric ion reducing power. The fatty acid profiles of plant parts were also determined by using gas chromatography. The total phenolic content of fruit (36.21mgGAE/g) was higher than that of mixed materials (13.79mgGAE/g). The methanolic extract of mixed material had higher amounts of flavonoid than fruit extract. The free radical scavenging activity of extracts was expressed as IC50 value (microg/mL) (amount required to inhibit DPPH radical formation by 50%). The lower IC50 value reflects better free radical scavenging action. The radical scavenging activity of the samples was compared with BHT, it showed the mixed material to be almost two times more potent than the fruit extract. However, BHT is an excellent free radical scavenger with an IC50 of 34.061 microg/mL. The ferric and cupric reducing power potentials of the extracts were expressed as EC50 value (the effective concentration at which the absorbance was 0.5). Fruit extract exhibited strong ferric reducing

  8. Fatty acid composition of lipopolysaccharides of the strains of different species of Yersinia.

    PubMed

    Frolov, A F; Ruban, N M; Vasyurenko, Z P

    1989-01-01

    The fatty acid composition of lipopolysaccharides of the strains of Y. enterocolitica, Y. intermedia, Y. frederiksenii and Y. ruckeri studied during cultivation on meat-peptone agar is characterized by the predominance of 3-hydroxytetradecanoic and dodecanoic acids. Closely related to the mentioned bacteria is the strain of Y. kristensenii which is distinguished only by its higher level of hexadecanoic acid. The strains of Y. pseudotuberculosis and the vaccine strain of Y. pestis have a uniform fatty acid composition of lipopolysaccharides with predominance of 3-hydroxytetradecanoic acid. Their relatively low level of dodecanoic acid conditions the characteristic fatty acid spectrum of lipopolysaccharides which differs from that of the above mentioned group of Yersinia. The peculiarities of the fatty acid composition of lipopolysaccharides of both groups of Yersinia are preserved during growth on meat-peptone broth, but the increase in the level of hexadecanoic acid balances the differences between Y. kristensenii, the other Y. enterocolitica-like bacteria and Y. ruckeri. The obtained results confirm close relationship of Y. pseudotuberculosis and Y. pestis, and also of Y. enterocolitica and Y. enterocolitica-like bacteria, showing propinquity of Y. ruckeri to the latter.

  9. Fatty acid composition and extreme temperature tolerance following exposure to fluctuating temperatures in a soil arthropod.

    PubMed

    van Dooremalen, Coby; Suring, Wouter; Ellers, Jacintha

    2011-09-01

    Ectotherms commonly adjust their lipid composition to ambient temperature to counteract detrimental thermal effects on lipid fluidity. However, the extent of lipid remodeling and the associated fitness consequences under continuous temperature fluctuations are not well-described. The objective of this study was to investigate the effect of repeated temperature fluctuations on fatty acid composition and thermal tolerance. We exposed the springtail Orchesella cincta to two constant temperatures of 5 and 20°C, and a continuously fluctuating treatment between 5 and 20°C every 2 days. Fatty acid composition differed significantly between constant low and high temperatures. As expected, animals were most cold tolerant in the low temperature treatment, while heat tolerance was highest under high temperature. Under fluctuating temperatures, fatty acid composition changed with temperature initially, but later in the experiment fatty acid composition stabilized and closely resembled that found under constant warm temperatures. Consistent with this, heat tolerance in the fluctuating temperature treatment was comparable to the constant warm treatment. Cold tolerance in the fluctuating temperature treatment was intermediate compared to animals acclimated to constant cold or warmth, despite the fact that fatty acid composition was adjusted to warm conditions. This unexpected finding suggests that in animals acclimated to fluctuating temperatures an additional underlying mechanism is involved in the cold shock response. Other aspects of homeoviscous adaptation may protect animals during extreme cold. This paper forms a next step to fully understand the functioning of ectotherms in more thermally variable environments. PMID:21704631

  10. Effects of dietary cottonseed oil and tannin supplements on protein and fatty acid composition of bovine milk.

    PubMed

    Aprianita, Aprianita; Donkor, Osaana N; Moate, Peter J; Williams, S Richard O; Auldist, Martin J; Greenwood, Jae S; Hannah, Murray C; Wales, William J; Vasiljevic, Todor

    2014-05-01

    This experiment was conducted to determine the effects of diets supplemented with cottonseed oil, Acacia mearnsii-condensed tannin extract, and a combination of both on composition of bovine milk. Treatment diets included addition of cottonseed oil (800 g/d; CSO), condensed tannin from Acacia mearnsii (400 g/d; TAN) or a combination of cottonseed oil (800 g/d) and condensed tannin (400 g/d; CPT) with a diet consisting of 6·0 kg dry matter (DM) of concentrates and alfalfa hay ad libitum, which also served as the control diet (CON). Relative to the CON diet, feeding CSO and CPT diets had a minor impact on feed intake and yield of lactose in milk. These diets increased yields of milk and protein in milk. In contrast to the TAN diet, the CSO and CPT diets significantly decreased milk fat concentration and altered milk fatty acid composition by decreasing the proportion of saturated fatty acids but increasing proportions of monounsaturated and polyunsaturated fatty acids. The CPT diet had a similar effect to the CSO diet in modifying fatty acid profile. Overall, reduction in milk fat concentration and changes in milk fatty acid profile were probably due to supplementation of linoleic acid-rich cottonseed oil. The TAN diet had no effect on feed intake, milk yield and milk protein concentration. However, a reduction in the yields of protein and lactose occurred when cows were fed this diet. Supplemented tannin had no significant effect on fat concentration and changes in fatty acid profile in milk. All supplemented diets did not affect protein concentration or composition, nitrogen concentration, or casein to total protein ratio of the resulting milk.

  11. The effects of 2-bromopalmitate on the fatty acid composition in differentiating adipocytes of red sea bream (Pagrus major).

    PubMed

    Oku, Hiromi; Tokuda, Masaharu; Umino, Tetsuya

    2009-04-01

    To determine whether external factors affect the adipogenic function of fish adipocytes, the effects of 2-bromopalmitate (a PPAR agonist) on the fatty acid composition in differentiating adipocytes of red sea bream were investigated in vitro. In the presence of 2-bromopalmitate, the red sea bream adipocytes were differentiated and the effects on the fatty acid composition and the adipogenic gene expression were analyzed. With the level of 2-bromopalmitate, the content of 16:1n-7, a delta-9 desaturation product, increased in association with the increase in a stearoyl CoA desaturase (SCD) gene expression level while the triglyceride accumulation was not affected. Subsequently, the effects on the bioconversion of the n-3 and n-6 fatty acids, which are main series of dietary essential fatty acids, were examined. In the presence of 300 microM of 18:3n-3 or 18:2n-6, red sea bream stromal-vascular cells accumulated the lipid in the cytoplasm within 3 days by the fatty acid uptake with the increase of corresponding fatty acid contents. Furthermore, in both the 18:3n-3 and 18:2n-6 stored cells, the products of delta-6 desaturation (18:4n-3 and 18:3n-6, respectively) and C(18-20) elongation (20:3n-3 and 20:2n-6, respectively) were detected. However, neither the delta-6 desatutration nor C(18-20) elongation of 18:3n-3 and 18:2n-6 were enhanced by 2-bromopalmitate treatment. In conclusion, the results indicate that the adipocyte function in fish, e.g. adipogenic gene expression and fatty acid composition, can be modified by external factors and a main effect of 2-bromopalmitate is the increase in the content of delta-9 desaturation product by stimulating the SCD gene expression.

  12. Simultaneous determination of mefenamic and tolfenamic acids in real samples by terbium-sensitized luminescence.

    PubMed

    Pulgarín, J A Murillo; Molina, A Alañón; Ferreras, F Martínez

    2012-11-01

    A simple luminescent methodology for the simultaneous determination of mefenamic and tolfenamic acids in pharmaceutical preparations and human urine is proposed. Since the native fluorescence of both analytes is not intense, the method takes advantage of the lanthanide-sensitized luminescence, which provides a higher sensitivity. Due to the strong overlapping between the luminescence spectra of both terbium complexes, the use of luminescence decay curves to resolve mixtures of the analytes is proposed, since these curves are more selective. A factorial design with three levels per factor coupled to a central composite design was selected to obtain a calibration matrix of thirteen standards plus eight blank samples that was processed using a partial least-squares (PLS) analysis. In order to assess the goodness of the proposed method, a prediction set of synthetic samples was analyzed, obtaining recovery percentages between 90 and 104 %. Limits of detection, calculated by means of a new criterion, were 14.85 μg L(-1) and 15.89 μg L(-1) for tolfenamic and mefenamic acids, respectively. The method was tested in a pharmaceutical preparation containing mefenamic acid, obtaining recovery percentages close to 100 %. Finally, the simultaneous determination of both fenamates in human urine samples was successfully carried out by means of a correction of the above-explained model. No extraction method neither prior separation of the analytes were needed.

  13. Fatty acid composition of cooked chicken meat and chicken meat products as influenced by price range at retail.

    PubMed

    Gibbs, Rachael A; Rymer, Caroline; Givens, D I

    2013-06-01

    The primary objective was to determine fatty acid composition of skinless chicken breast and leg meat portions and chicken burgers and nuggets from the economy price range, standard price range (both conventional intensive rearing) and the organic range from four leading supermarkets. Few significant differences in the SFA, MUFA and PUFA composition of breast and leg meat portions were found among price ranges, and supermarket had no effect. No significant differences in fatty acid concentrations of economy and standard chicken burgers were found, whereas economy chicken nuggets had higher C16:1, C18:1 cis, C18:1 trans and C18:3 n-3 concentrations than had standard ones. Overall, processed chicken products had much higher fat contents and SFA than had whole meat. Long chain n-3 fatty acids had considerably lower concentrations in processed products than in whole meat. Overall there was no evidence that organic chicken breast or leg meat had a more favourable fatty acid composition than had meat from conventionally reared birds.

  14. Quality assessment of Iberian pigs through backfat ultrasound characterization and fatty acid composition.

    PubMed

    Niñoles, L; Clemente, G; Ventanas, S; Benedito, J

    2007-05-01

    Five batches of Iberian pig backfat of different breeds and with differing feeding regimes were analysed as to their fatty acid composition and textural, thermal and ultrasonic properties. The feeding regime affected the backfat composition more than the breed of the animals. The higher the oleic acid content in the feeding regime, the higher the monounsaturated fatty acid content in the samples. Ultrasonic velocities ranged from 1609 to 1631m/s. A change in the slope of the velocity versus temperature curve was found at 6°C, coincident with a change in the melting rate found in the differential scanning calorimetry. Discriminant analysis using ultrasonic measurements allowed 94.7% of the samples to be correctly classified in the batches considered, while the use of the fatty acids composition correctly classified 86.2% of the samples. Therefore, ultrasonic techniques could be useful in the characterization and classification of backfat samples from Iberian pigs.

  15. Simultaneous Determination of Salicylic Acid, Jasmonic Acid, Methyl Salicylate, and Methyl Jasmonate from Ulmus pumila Leaves by GC-MS.

    PubMed

    Huang, Zhi-Hong; Wang, Zhi-Li; Shi, Bao-Lin; Wei, Dong; Chen, Jian-Xin; Wang, Su-Li; Gao, Bao-Jia

    2015-01-01

    Salicylic acid, jasmonic acid, methyl salicylate, and methyl jasmonate are important phytohormones and defensive signaling compounds, so it is of great importance to determine their levels rapidly and accurately. The study uses Ulmus pumila leaves infected by Tetraneura akinire Sasaki at different stages as materials; after extraction with 80% methanol and ethyl acetate and purification with primary secondary amine (PSA) and graphitized carbon blacks (GCB), the contents of signal compounds salicylic acid, jasmonic acid, methyl salicylate, and methyl jasmonate were determined by GC-MS. The results showed that the level of salicylic acid, jasmonic acid, methyl salicylate, and methyl jasmonate increased remarkably in U. pumila once infected by T. akinire Sasaki, but the maximums of these four compounds occurred at different times. Salicylic acid level reached the highest at the early stage, and jasmonic acid level went to the maximum in the middle stage; by contrast, change of content of methyl salicylate and methyl jasmonate was the quite opposite. PMID:26457083

  16. Simultaneous Determination of Salicylic Acid, Jasmonic Acid, Methyl Salicylate, and Methyl Jasmonate from Ulmus pumila Leaves by GC-MS

    PubMed Central

    Huang, Zhi-hong; Wang, Zhi-li; Shi, Bao-lin; Wei, Dong; Chen, Jian-xin; Wang, Su-li; Gao, Bao-jia

    2015-01-01

    Salicylic acid, jasmonic acid, methyl salicylate, and methyl jasmonate are important phytohormones and defensive signaling compounds, so it is of great importance to determine their levels rapidly and accurately. The study uses Ulmus pumila leaves infected by Tetraneura akinire Sasaki at different stages as materials; after extraction with 80% methanol and ethyl acetate and purification with primary secondary amine (PSA) and graphitized carbon blacks (GCB), the contents of signal compounds salicylic acid, jasmonic acid, methyl salicylate, and methyl jasmonate were determined by GC-MS. The results showed that the level of salicylic acid, jasmonic acid, methyl salicylate, and methyl jasmonate increased remarkably in U. pumila once infected by T. akinire Sasaki, but the maximums of these four compounds occurred at different times. Salicylic acid level reached the highest at the early stage, and jasmonic acid level went to the maximum in the middle stage; by contrast, change of content of methyl salicylate and methyl jasmonate was the quite opposite. PMID:26457083

  17. Non-invasive techniques for determining musculoskeleton body composition

    SciTech Connect

    Cohn, S.H.

    1984-01-01

    In vivo neutron activation analysis, combined with gamma spectrometry, has ushered in a new era of clinical diagnosis and evaluation of therapies, as well as investigation into and modelling of body composition in both normal individuals and patients suffering from various diseases and dysfunctions. Body composition studies have provided baseline data on such vital constituents as nitrogen, potassium and calcium. The non-invasive measurement techniques are particularly suitable for study of the musculo-skeletal changes in body composition. Of particular relevance here is the measurement of calcium loss in astronauts during prolonged space flights.

  18. Molecular distributions and isotopic compositions of marine aerosols over the western North Atlantic: Dicarboxylic acids, ketoacids, α-dicarbonyls (glyoxal and methylglyoxal), fatty acids, sugars, and SOA tracers

    NASA Astrophysics Data System (ADS)

    Kawamura, K.; Ono, K.; Tachibana, E.; Quinn, P.; Bates, T. S.

    2013-12-01

    Marine aerosols were collected over the western North Atlantic from off the coast of Boston to Bermuda during the WACS (Western Atlantic Climate Study) cruise of R/V Ronald H. Brown in August 2012 using a high volume air sampler and pre-combusted quartz fiber filters. Aerosol filter samples (n=5) were analyzed for OC/EC, major inorganic ions, low molecular weight dicarboxylic acids and various secondary organic aerosol (SOA) tracers using carbon analyzer, ion chromatograph, GC/FID and GC/MS, respectively. Homologous series (C2-C12) of dicarboxylic acids (31-335 ng m-3) were detected with a predominance of oxalic acid. Total carbon and nitrogen and their stable isotope ratios were determined as well as stable carbon isotopic compositions of individual diacids using IRMS. Diacids were found to be the most abundant compound class followed by monoterpene-SOA tracers > isoprene-SOA tracers > sugar compounds > ketoacids > fatty alcohols > fatty acids > α-dicarbonyls > aromatic acids > n-alkanes. The concentrations of these compounds were higher in the coastal site and decreased in the open ocean. However, diacids stayed relatively high even in the remote ocean. Interestingly, contributions of oxalic acid to total aerosol carbon increased from the coast (2.3%) to the remote ocean (5.6%) during long-range atmospheric transport. Stable carbon isotopic composition of oxalic acid increased from the coast (-17.5‰) to open ocean (-12.4‰), suggesting that photochemical aging of organic aerosols occurred during the atmospheric transport over the ocean. Stable carbon isotope ratios of bulk aerosol carbon also increased from the coast near Boston to the open ocean near Bermuda.

  19. Thermoformed protein based composites in presence of organic acids

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  20. A method for the determination of the carbon chain length composition of amine oxides.

    PubMed

    Langley, N A; Suddaby, D; Coupland, K

    1988-12-01

    Synopsis Alkylamine oxides and alkylamidopropyldimethylamine oxides belong to an important group of surfactant materials. They are used extensively in formulations for cosmetics, toiletries and household products. Although there are numerous analytical methods available to evaluate physical and chemical properties of these compounds, there remains a demand for a qualitative method for the determination of the carbon chain length composition. Amine oxides cannot be analysed directly by gas liquid chromatography (GLC) as they decompose at temperatures above 100 degrees C to give the terminal alkenes and tertiary amines. However, amine oxides can be analysed by GLC if they are first reduced to the tertiary amines. Examples of each type of amine oxide were reduced with triphenylphosphine in boiling glacial acetic acid between 1 and 1.5 h. In this paper a rapid qualitative analytical procedure is described. PMID:19456939

  1. Determining Phthalic Acid Esters Using Terahertz Time Domain Spectroscopy

    NASA Astrophysics Data System (ADS)

    Liu, L.; Shen, L.; Yang, F.; Han, F.; Hu, P.; Song, M.

    2016-09-01

    In this report terahertz time domain spectroscopy (THz-TDS) is applied for determining phthalic acid esters (PAEs) in standard materials. We reported the THz transmission spectrum in the frequency range of 0.2 to 2.0 THz for three PAEs: di-n-butyl phthalate (DBP), di-isononyl phthalate (DINP), and di-2-ethylhexyl phthalate ester (DEHP). The study provided the refractive indices and absorption features of these materials. The absorption spectra of three PAEs were simulated by using Gaussian software with Density Functional Theory (DFT) methods. For pure standard PAEs, the values of the refractive indices changed between 1.50 and 1.60. At 1.0 THz, the refractive indices were 1.524, 1.535, and 1.563 for DINP, DEHP, and DBP, respectively. In this experiment different concentrations of DBP were investigated using THz-TDS. Changes were measured in the low THz frequency range for refractive indices and characteristic absorption. The results indicated that THz-TDS is promising as a new method in determining PAEs in many materials. The results of this study could be used to support the practical application of THz-TDS in quality detection and food monitoring. In particular, this new technique could be used in detecting hazardous materials and other substances present in wine or foods.

  2. Annual cycle and spatial trends in fatty acid composition of suspended particulate organic matter across the Beaufort Sea shelf

    NASA Astrophysics Data System (ADS)

    Connelly, Tara L.; Businski, Tara N.; Deibel, Don; Parrish, Christopher C.; Trela, Piotr

    2016-11-01

    Fatty acid profiles of suspended particulate organic matter (POM) were determined over an annual cycle (September 2003 to August 2004) on the Beaufort Sea shelf, Canadian Arctic. Special emphasis was placed on the nutritional quality of the fatty acid pool available to zooplankton by examining spatial and temporal patterns in the proportions of total polyunsaturated fatty acids (PUFA) and the essential fatty acids 22:6n-3 (DHA) and 20:5n-3 (EPA). EPA and DHA were the two most abundant PUFA throughout the study period. A log-ratio multivariate (LRA) analysis revealed strong structure in fatty acid profiles related to season and depth. Dominant fatty acids accounting for the observed trend included 18:5n-3, 18:4n-3, 16:1n-7, 20:5n-3, 18:0 and 20:3n-3. We observed a shift in fatty acid profiles from summer to autumn (e.g., from 16:1n-7 and EPA to 18:5n-3 and 18:4n-3) that likely corresponded to a shift in the relative importance of diatoms versus dinoflagellates, prymnesiophytes and/or prasinophytes to the POM pool. Fatty acid composition during winter was dominated by more refractory saturated fatty acids. A surprising finding was the depth and seasonal trend of 20:3n-3, which was higher in winter, aligned with 18:0 in the LRA, but behaved differently than other n-3 PUFA. We interpret fatty acid profiles during summer to be predominantly driven by phytoplankton inputs, whereas fatty acid profiles in winter were dominated by fatty acids that were left over after consumption and/or were generated by heterotrophs. The highest diatom inputs (EPA, the diatom fatty acid marker), n-3/n-6 ratios, and C16 PUFA index were located in an upwelling region off Cape Bathurst. This study is the first annual time series of fatty acid profiles of POM in Arctic seas, expanding our knowledge of the composition of POM throughout the dark season.

  3. Amino acid composition and amino acid-metabolic network in supragingival plaque.

    PubMed

    Washio, Jumpei; Ogawa, Tamaki; Suzuki, Keisuke; Tsukiboshi, Yosuke; Watanabe, Motohiro; Takahashi, Nobuhiro

    2016-01-01

    Dental plaque metabolizes both carbohydrates and amino acids. The former can be degraded to acids mainly, while the latter can be degraded to various metabolites, including ammonia, acids and amines, and associated with acid-neutralization, oral malodor and tissue inflammation. However, amino acid metabolism in dental plaque is still unclear. This study aimed to elucidate what kinds of amino acids are available as metabolic substrates and how the amino acids are metabolized in supragingival plaque, by a metabolome analysis. Amino acids and the related metabolites in supragingival plaque were extracted and quantified comprehensively by CE-TOFMS. Plaque samples were also incubated with amino acids, and the amounts of ammonia and amino acid-related metabolites were measured. The concentration of glutamate was the highest in supragingival plaque, while the ammonia-production was the highest from glutamine. The obtained metabolome profile revealed that amino acids are degraded through various metabolic pathways, including deamination, decarboxylation and transamination and that these metabolic systems may link each other, as well as with carbohydrate metabolic pathways in dental plaque ecosystem. Moreover, glutamine and glutamate might be the main source of ammonia production, as well as arginine, and contribute to pH-homeostasis and counteraction to acid-induced demineralization in supragingival plaque. PMID:27545001

  4. Fatty Acids Composition of Vegetable Oils and Its Contribution to Dietary Energy Intake and Dependence of Cardiovascular Mortality on Dietary Intake of Fatty Acids

    PubMed Central

    Orsavova, Jana; Misurcova, Ladislava; Vavra Ambrozova, Jarmila; Vicha, Robert; Mlcek, Jiri

    2015-01-01

    Characterizations of fatty acids composition in % of total methylester of fatty acids (FAMEs) of fourteen vegetable oils—safflower, grape, silybum marianum, hemp, sunflower, wheat germ, pumpkin seed, sesame, rice bran, almond, rapeseed, peanut, olive, and coconut oil—were obtained by using gas chromatography (GC). Saturated (SFA), monounsaturated (MUFA) and polyunsaturated fatty acids (PUFA), palmitic acid (C16:0; 4.6%–20.0%), oleic acid (C18:1; 6.2%–71.1%) and linoleic acid (C18:2; 1.6%–79%), respectively, were found predominant. The nutritional aspect of analyzed oils was evaluated by determination of the energy contribution of SFAs (19.4%–695.7% ERDI), PUFAs (10.6%–786.8% ERDI), n-3 FAs (4.4%–117.1% ERDI) and n-6 FAs (1.8%–959.2% ERDI), expressed in % ERDI of 1 g oil to energy recommended dietary intakes (ERDI) for total fat (ERDI—37.7 kJ/g). The significant relationship between the reported data of total fat, SFAs, MUFAs and PUFAs intakes (% ERDI) for adults and mortality caused by coronary heart diseases (CHD) and cardiovascular diseases (CVD) in twelve countries has not been confirmed by Spearman’s correlations. PMID:26057750

  5. Fatty Acids Composition of Vegetable Oils and Its Contribution to Dietary Energy Intake and Dependence of Cardiovascular Mortality on Dietary Intake of Fatty Acids.

    PubMed

    Orsavova, Jana; Misurcova, Ladislava; Ambrozova, Jarmila Vavra; Vicha, Robert; Mlcek, Jiri

    2015-06-05

    Characterizations of fatty acids composition in % of total methylester of fatty acids (FAMEs) of fourteen vegetable oils--safflower, grape, silybum marianum, hemp, sunflower, wheat germ, pumpkin seed, sesame, rice bran, almond, rapeseed, peanut, olive, and coconut oil--were obtained by using gas chromatography (GC). Saturated (SFA), monounsaturated (MUFA) and polyunsaturated fatty acids (PUFA), palmitic acid (C16:0; 4.6%-20.0%), oleic acid (C18:1; 6.2%-71.1%) and linoleic acid (C18:2; 1.6%-79%), respectively, were found predominant. The nutritional aspect of analyzed oils was evaluated by determination of the energy contribution of SFAs (19.4%-695.7% E(RDI)), PUFAs (10.6%-786.8% E(RDI)), n-3 FAs (4.4%-117.1% E(RDI)) and n-6 FAs (1.8%-959.2% E(RDI)), expressed in % E(RDI) of 1 g oil to energy recommended dietary intakes (E(RDI)) for total fat (E(RDI)--37.7 kJ/g). The significant relationship between the reported data of total fat, SFAs, MUFAs and PUFAs intakes (% E(RDI)) for adults and mortality caused by coronary heart diseases (CHD) and cardiovascular diseases (CVD) in twelve countries has not been confirmed by Spearman's correlations.

  6. Fatty Acids Composition of Vegetable Oils and Its Contribution to Dietary Energy Intake and Dependence of Cardiovascular Mortality on Dietary Intake of Fatty Acids.

    PubMed

    Orsavova, Jana; Misurcova, Ladislava; Ambrozova, Jarmila Vavra; Vicha, Robert; Mlcek, Jiri

    2015-01-01

    Characterizations of fatty acids composition in % of total methylester of fatty acids (FAMEs) of fourteen vegetable oils--safflower, grape, silybum marianum, hemp, sunflower, wheat germ, pumpkin seed, sesame, rice bran, almond, rapeseed, peanut, olive, and coconut oil--were obtained by using gas chromatography (GC). Saturated (SFA), monounsaturated (MUFA) and polyunsaturated fatty acids (PUFA), palmitic acid (C16:0; 4.6%-20.0%), oleic acid (C18:1; 6.2%-71.1%) and linoleic acid (C18:2; 1.6%-79%), respectively, were found predominant. The nutritional aspect of analyzed oils was evaluated by determination of the energy contribution of SFAs (19.4%-695.7% E(RDI)), PUFAs (10.6%-786.8% E(RDI)), n-3 FAs (4.4%-117.1% E(RDI)) and n-6 FAs (1.8%-959.2% E(RDI)), expressed in % E(RDI) of 1 g oil to energy recommended dietary intakes (E(RDI)) for total fat (E(RDI)--37.7 kJ/g). The significant relationship between the reported data of total fat, SFAs, MUFAs and PUFAs intakes (% E(RDI)) for adults and mortality caused by coronary heart diseases (CHD) and cardiovascular diseases (CVD) in twelve countries has not been confirmed by Spearman's correlations. PMID:26057750

  7. Nutritional value of 15 corn gluten meals for growing pigs: chemical composition, energy content and amino acid digestibility.

    PubMed

    Ji, Ying; Zuo, Lei; Wang, Fengli; Li, Defa; Lai, Changhua

    2012-08-01

    The objectives of this study were to determine the chemical composition, energy content and amino acid digestibility for corn gluten meals (CGM) and to develop prediction equations for estimating energy content and amino acid digestibility for growing pigs based on the chemical characteristics of these meals. The 15 CGM tested were obtained from seven Chinese companies. Experiment 1 was conducted to determine the digestible (DE) and metabolisable energy (ME) of the 15 CGM. The 18 growing barrows (38 +/- 4 kg) were assigned to three 6 x 6 Latin square designs. The 15 CGM test diets were formulated to contain 19.20% CGM, which replaced 20% of the energy supplied by corn and crystalline amino acid in the basal diet. Experiment 2 was conducted to determine the apparent (AID) and standardised (SID) ileal digestibility of the crude protein (CP) and amino acids in the 15 CGM using chromic oxide as an inert marker. The 18 growing barrows (25 +/- 2 kg) fitted with a simple T-cannula were assigned to three 6 x 6 Latin square designs. The 15 test diets contained 35% of one of the 15 CGM as the sole source of amino acids in the diet. The results showed a considerable variation in the chemical composition of CGM within and among plants. On dry matter basis, the DE and ME content of the CGM ranged from 18.8 to 21.0 MJ/kg and from 18.0 to 19.9 MJ/kg, respectively. There were no significant differences in the AID and SID for CP, arginine, lysine, glycine and proline among the 15 CGM, however, for all the other amino acids, significant differences were found for their AID and SID. With R2 values exceeding 0.50, the DE of CGM can be predicted accurately from CP and fibre content and ME from starch and fibre content. Suitable prediction equations for SID of methionine were also developed.

  8. Synthesis and swelling behavior of Protein-g-poly Methacrylic acid/kaolin superabsorbent hydrogel composites

    NASA Astrophysics Data System (ADS)

    Sadeghi, Mohammad

    2008-08-01

    A novel superabsorbent hydrogel composite based on Collagen have been prepared via graft copolymerization of Methacrylic acid (MAA) in the presence of kaolin powder using methylenebisacrylamide (MBA) as a crosslinking agent and ammonium persulfate (APS) as an initiator. The composite structure was confirmed using FTIR spectroscopy. A new absorption band at 1728 cm-1 in the composite spectrum confirmed kaolin-organic polymer linkage. The effect of kaolin amount and MBA concentration showed that with increasing of these parameters, the water absorbency of the superabsorbent composite was decreased. The swelling measurements of the hydrogels were conducted in aqueous salt solutions.

  9. [Study on ionic composition of rainwater at Guangzhou and the primary factors of rainwater acidity].

    PubMed

    Liu, Jun-feng; Song, Zhi-guang; Xu, Tao

    2006-10-01

    All rainwater samples were collected during the period Oct. 2003 to Sep. 2004 and analysed in terms of pH values, major cation, anion composition and soluble organic carbon (DOC). The measurement of pH values shows that 85% of these rain events were acid rain. The ionic composition analysis indicates that NO3-, SO4(2-), NH4+ and Ca2+ are dominant ions in the rainwater. DOC approximately consisted of 24.0% of total chemical components. Although SO4(2-) remains the dominant acidic ion in term of concentration, NO3- has become very important to the acidity of rainwater and as well as the organic acids. Furthermore, dust sourced Ca2+ appears to play significant role in neutralizing the acidity in rainwater.

  10. Potentiometric determination of free acidity in uranium(VI) and plutonium(IV) solutions and a sequential determination of uranium

    SciTech Connect

    Ahmed, M.K.; Suryanarayana, D.S.; Sabharwal, K.N.; Sreenivasan, N.L.

    1985-10-01

    Free acidity in uranium(VI) and plutonium(IV) solutions has been determined with sodium sulfate as complexant and sodium carbonate as titrant. The described method is simple, accurate, and applicable to all ranges of nitric acid and heavy metal concentrations relevant to Purex process. The method is adaptable for remote operation. The overall recovery of nitric acid is 99.5% with 0.7% relative standard deviation. Uranium content has also been determined in the same aliquot with a recovery of 98.5% and 1.2% relative standard deviation after the determination of acidity.

  11. Fatty acid composition of beef is associated with exonic nucleotide variants of the gene encoding FASN.

    PubMed

    Oh, Dongyep; Lee, Yoonseok; La, Boomi; Yeo, Jungsou; Chung, Euiryong; Kim, Younyoung; Lee, Chaeyoung

    2012-04-01

    Genetic associations of fatty acid composition with exonic single nucleotide polymorphisms (SNPs) in the gene encoding fatty acid synthase (FASN) were examined using 513 Korean cattle. All five individual SNPs of g.12870 T>C, g.13126 T>C, g.15532 C>A, g.16907 T>C and g.17924 G>A were associated with a variety of fatty acid compositions and further with marbling score (P < 0.05). Their genotypes of CC, TT, AA, TT, and GG were associated with increased monounsaturated fatty acids and with decreased saturated fatty acids (P < 0.05). The genotypes at all the SNPs also increased marbling score (P < 0.05). Further genetic associations with fatty acid composition suggested that homozygous genotype with the haplotype of ATG at g.15532, g.16907, and g.17924 in a linkage disequilibrium block increased monounsaturated fatty acids and marbling score (P < 0.05). We concluded that the five exonic SNPs of g.12870, g.13126, g.15532, g.16907, and g.17924 in the FASN gene could change fatty acid contents. Their genotypes of CC, TT, AA, TT, and GG and haplotype of ATG at g.15532, g.16907, and g.17924 were recommended for genetic improvement of beef quality.

  12. Synthesis of Au/Graphene Oxide Composites for Selective and Sensitive Electrochemical Detection of Ascorbic Acid

    PubMed Central

    Song, Jian; Xu, Lin; Xing, Ruiqing; Li, Qingling; Zhou, Chunyang; Liu, Dali; Song, Hongwei

    2014-01-01

    In this work, we present a novel ascorbic acid (AA) sensor applied to the detection of AA in human sera and pharmaceuticals. A series of Au nanoparticles (NPs) and graphene oxide sheets (Au NP/GO) composites were successfully synthesized by reduction of gold (III) using sodium citrate. Then the Au NP/GO composites were used to construct nonenzymatic electrodes in practical AA measurement. The electrode that has the best performance presents attractive analytical features, such as a low working potential of +0.15 V, a high sensitivity of 101.86 μA mM−1 cm−2 to AA, a low detection limit of 100 nM, good reproducibility and excellent selectivity. And more,it was also employed to accurately and practically detect AA in human serum and clinical vitamin C tablet with the existence of some food additive. The enhanced AA electrochemical properties of the Au NP/GO modified electrode in our work can be attributed to the improvement of electroactive surface area of Au NPs and the synergistic effect from the combination of Au NPs and GO sheets. This work shows that the Au NP/GO/GCEs hold the prospect for sensitive and selective determination of AA in practical clinical application. PMID:25515430

  13. Synthesis of Au/Graphene Oxide Composites for Selective and Sensitive Electrochemical Detection of Ascorbic Acid

    NASA Astrophysics Data System (ADS)

    Song, Jian; Xu, Lin; Xing, Ruiqing; Li, Qingling; Zhou, Chunyang; Liu, Dali; Song, Hongwei

    2014-12-01

    In this work, we present a novel ascorbic acid (AA) sensor applied to the detection of AA in human sera and pharmaceuticals. A series of Au nanoparticles (NPs) and graphene oxide sheets (Au NP/GO) composites were successfully synthesized by reduction of gold (III) using sodium citrate. Then the Au NP/GO composites were used to construct nonenzymatic electrodes in practical AA measurement. The electrode that has the best performance presents attractive analytical features, such as a low working potential of +0.15 V, a high sensitivity of 101.86 μA mM-1 cm-2 to AA, a low detection limit of 100 nM, good reproducibility and excellent selectivity. And more,it was also employed to accurately and practically detect AA in human serum and clinical vitamin C tablet with the existence of some food additive. The enhanced AA electrochemical properties of the Au NP/GO modified electrode in our work can be attributed to the improvement of electroactive surface area of Au NPs and the synergistic effect from the combination of Au NPs and GO sheets. This work shows that the Au NP/GO/GCEs hold the prospect for sensitive and selective determination of AA in practical clinical application.

  14. Synthesis of Au/graphene oxide composites for selective and sensitive electrochemical detection of ascorbic acid.

    PubMed

    Song, Jian; Xu, Lin; Xing, Ruiqing; Li, Qingling; Zhou, Chunyang; Liu, Dali; Song, Hongwei

    2014-01-01

    In this work, we present a novel ascorbic acid (AA) sensor applied to the detection of AA in human sera and pharmaceuticals. A series of Au nanoparticles (NPs) and graphene oxide sheets (Au NP/GO) composites were successfully synthesized by reduction of gold (III) using sodium citrate. Then the Au NP/GO composites were used to construct nonenzymatic electrodes in practical AA measurement. The electrode that has the best performance presents attractive analytical features, such as a low working potential of +0.15 V, a high sensitivity of 101.86 μA mM(-1) cm(-2) to AA, a low detection limit of 100 nM, good reproducibility and excellent selectivity. And more,it was also employed to accurately and practically detect AA in human serum and clinical vitamin C tablet with the existence of some food additive. The enhanced AA electrochemical properties of the Au NP/GO modified electrode in our work can be attributed to the improvement of electroactive surface area of Au NPs and the synergistic effect from the combination of Au NPs and GO sheets. This work shows that the Au NP/GO/GCEs hold the prospect for sensitive and selective determination of AA in practical clinical application. PMID:25515430

  15. Synthesis of Au/graphene oxide composites for selective and sensitive electrochemical detection of ascorbic acid.

    PubMed

    Song, Jian; Xu, Lin; Xing, Ruiqing; Li, Qingling; Zhou, Chunyang; Liu, Dali; Song, Hongwei

    2014-12-17

    In this work, we present a novel ascorbic acid (AA) sensor applied to the detection of AA in human sera and pharmaceuticals. A series of Au nanoparticles (NPs) and graphene oxide sheets (Au NP/GO) composites were successfully synthesized by reduction of gold (III) using sodium citrate. Then the Au NP/GO composites were used to construct nonenzymatic electrodes in practical AA measurement. The electrode that has the best performance presents attractive analytical features, such as a low working potential of +0.15 V, a high sensitivity of 101.86 μA mM(-1) cm(-2) to AA, a low detection limit of 100 nM, good reproducibility and excellent selectivity. And more,it was also employed to accurately and practically detect AA in human serum and clinical vitamin C tablet with the existence of some food additive. The enhanced AA electrochemical properties of the Au NP/GO modified electrode in our work can be attributed to the improvement of electroactive surface area of Au NPs and the synergistic effect from the combination of Au NPs and GO sheets. This work shows that the Au NP/GO/GCEs hold the prospect for sensitive and selective determination of AA in practical clinical application.

  16. The influence of a vegetarian diet on the fatty acid composition of human milk and the essential fatty acid status of the infant.

    PubMed

    Sanders, T A; Reddy, S

    1992-04-01

    Vegan and vegetarian diets supply higher amounts of linoleic acid than those of omnivores. Intakes of alpha-linolenic acid (18:3n-3) are variable, depending on the oils used, but are generally high in vegans. Docosahexaenoic acid (22:6n-3) (DHA) is absent from vegan and many vegetarian diets. Cord plasma and cord artery phospholipid levels of Hindu vegetarians contained less DHA and more docosapentaenoic acid (22:5n-6) compared with those of omnivore control subjects. These differences in fatty acid composition were not statistically related to differences in birth weight, head circumference, or length. In human milk from vegans, vegetarians, and omnivores, the mean percentage in total fatty acids of 18:2n-6 was 23.8%, 19.7%, and 10.9%, respectively; that of 18:3n-3 was 1.36%, 1.25%, and 0.49%, respectively; and that of 22:6n-3 was 0.14%, 0.30%, and 0.37%, respectively. The proportion of DHA in erythrocyte total lipids of infants breast-fed by vegans was 1.9% compared with 3.7% in infants fed a milk formula containing butterfat as the sole source of fat and 6.2% in infants breast-fed by omnivores at 14 weeks postpartum. The ratio of linoleic/alpha-linolenic acid in the diet was predictive of the proportion of eicosapentaenoic acid but not that of DHA in infant red blood cell lipids. It is concluded that the intakes of linoleic acid and DHA are the major determinants of the proportion of DHA in plasma and red blood cell lipids.

  17. The influence of a vegetarian diet on the fatty acid composition of human milk and the essential fatty acid status of the infant.

    PubMed

    Sanders, T A; Reddy, S

    1992-04-01

    Vegan and vegetarian diets supply higher amounts of linoleic acid than those of omnivores. Intakes of alpha-linolenic acid (18:3n-3) are variable, depending on the oils used, but are generally high in vegans. Docosahexaenoic acid (22:6n-3) (DHA) is absent from vegan and many vegetarian diets. Cord plasma and cord artery phospholipid levels of Hindu vegetarians contained less DHA and more docosapentaenoic acid (22:5n-6) compared with those of omnivore control subjects. These differences in fatty acid composition were not statistically related to differences in birth weight, head circumference, or length. In human milk from vegans, vegetarians, and omnivores, the mean percentage in total fatty acids of 18:2n-6 was 23.8%, 19.7%, and 10.9%, respectively; that of 18:3n-3 was 1.36%, 1.25%, and 0.49%, respectively; and that of 22:6n-3 was 0.14%, 0.30%, and 0.37%, respectively. The proportion of DHA in erythrocyte total lipids of infants breast-fed by vegans was 1.9% compared with 3.7% in infants fed a milk formula containing butterfat as the sole source of fat and 6.2% in infants breast-fed by omnivores at 14 weeks postpartum. The ratio of linoleic/alpha-linolenic acid in the diet was predictive of the proportion of eicosapentaenoic acid but not that of DHA in infant red blood cell lipids. It is concluded that the intakes of linoleic acid and DHA are the major determinants of the proportion of DHA in plasma and red blood cell lipids. PMID:1560329

  18. Spectrophotometric determination of nitrite in soil and water using cefixime and central composite design.

    PubMed

    Shariati-Rad, Masoud; Irandoust, Mohsen; Mohammadi, Shabnam

    2015-01-01

    The present paper seeks to develop a simple method for the spectrophotometric determination of nitrite in soil and water samples and also measure optimum reaction conditions along with other analytical parameters. The method is based on the diazotization-coupling reaction of nitrite with cefixime and 1-naphthylamine in an acidic solution (Griess reaction). The final product that is an azo dye has an orange color with maximum absorption at 360 nm which Beer's Law is obeyed over the concentration range 0.02-15.00 mg L(-1) of nitrite. Optimal conditions of the variables affecting the reaction were obtained by central composite design (CCD). A detection limit of 4.3×10(-3) mg L(-1) was obtained for determination of nitrite by the proposed method. The proposed method was successfully applied to determine nitrite in soil and water samples. The molar absorptivity of the product of the reaction and RSD in determination of nitrite in real samples are 4.1×10(3) (L mol(-1) cm(-1)) and lower than 10%, respectively.

  19. Spectrophotometric determination of nitrite in soil and water using cefixime and central composite design

    NASA Astrophysics Data System (ADS)

    Shariati-Rad, Masoud; Irandoust, Mohsen; Mohammadi, Shabnam

    2015-10-01

    The present paper seeks to develop a simple method for the spectrophotometric determination of nitrite in soil and water samples and also measure optimum reaction conditions along with other analytical parameters. The method is based on the diazotization-coupling reaction of nitrite with cefixime and 1-naphthylamine in an acidic solution (Griess reaction). The final product that is an azo dye has an orange color with maximum absorption at 360 nm which Beer's Law is obeyed over the concentration range 0.02-15.00 mg L-1 of nitrite. Optimal conditions of the variables affecting the reaction were obtained by central composite design (CCD). A detection limit of 4.3 × 10-3 mg L-1 was obtained for determination of nitrite by the proposed method. The proposed method was successfully applied to determine nitrite in soil and water samples. The molar absorptivity of the product of the reaction and RSD in determination of nitrite in real samples are 4.1 × 103 (L mol-1 cm-1) and lower than 10%, respectively.

  20. Tissue Composition Determination via Measurement of the Acoustic Nonlinearity Parameter

    NASA Astrophysics Data System (ADS)

    Everbach, Erich Carr

    In this thesis, methods are described by which the concentrations of water, protein, and fat present in a biological tissue can be inferred from measurements made of its bulk acoustic properties, including the acoustic nonlinearity parameter, B/A. We review the physical significance of this parameter and its use as a descriptor in the mixture methodologies of Apfel and Sehgal et al., and explore the theoretical implications of both methodologies and their underlying relations. One important result is that Apfel's methodology applies strictly only to mixtures whose components are finely mixed on the scale of an acoustic wavelength, while Sehgal's methodology applies strictly only to mixtures whose components are arranged in layers or regions of thickness (in the direction of propagation) larger than an acoustic wavelength. Another result is the prediction of a mechanism for enhanced nonlinearity based upon the application of Apfel's perfect-mixture relation for B/A to gas-liquid mixtures. Also in this thesis we describe a new in vitro technique for precise determination of B/A, and use this technique to measure a wide range of protein solutions, lipid oils, and their mixtures, as well as biological tissues. On the basis of these data, we compare and evaluate the mixture methodologies and suggest ways in which these models may be improved and extended. We show that when Apfel's and Sehgal's methodologies are applied to fine and coarse mixtures, respectively, they predict the actual component volume fractions to an accuracy of within 5%. For two-component mixtures, the perfect-mixture relations involving density, sound speed and B/A were obeyed to within about 2%, 3%, and 5%, respectively. For protein solutions, no dependence of B/A with protein molecular weight was observed. Also, no significant dependence of B/A or the inferred component volume fractions was observed for changes in tissue structure including denaturization of proteins, clotting of blood plasma

  1. Stable carbon isotopic compositions of low-molecular-weight dicarboxylic acids, oxocarboxylic acids, α-dicarbonyls, and fatty acids: Implications for atmospheric processing of organic aerosols

    NASA Astrophysics Data System (ADS)

    Zhang, Yan-Lin; Kawamura, Kimitaka; Cao, Fang; Lee, Meehye

    2016-04-01

    Stable carbon isotopic compositions (δ13C) were measured for 23 individual organic species including 9 dicarboxylic acids, 7 oxocarboxylic acids, 1 tricarboxylic acid, 2 α-dicarbonyls, and 4 fatty acids in the aerosols from Gosan background site in East Asia. δ13C values of particle phase glyoxal and methylglyoxal are significantly larger than those previously reported for isoprene and other precursors. The values are consistently less negative in oxalic acid (C2, average -14.1‰), glyoxylic acid (-13.8‰), pyruvic acid (-19.4‰), glyoxal (-13.5‰), and methylglyoxal (-18.6‰) compared to other organic species (e.g., palmitic acid, -26.3‰), which can be explained by the kinetic isotope effects during atmospheric oxidation of pre-aged precursors (e.g., isoprene) and the subsequent gas-particle partitioning after the evaporation of clouds or wet aerosols. The δ13C values of C2 is positively correlated with C2 to organic carbon ratio, indicating that photochemical production of C2 is more pronounced than its degradation during long-range atmospheric transport. The isotopic results also suggest that aqueous phase oxidation of glyoxal and methylglyoxal is a major formation process of oxalic acid via the intermediates such as glyoxylic acid and pyruvic acid. This study provides evidence that organic aerosols are intensively photochemically aged in the western North Pacific rim.

  2. BASE COMPOSITION OF THE DEOXYRIBONUCLEIC ACID OF SULFATE-REDUCING BACTERIA

    PubMed Central

    Sigal, Nicole; Senez, Jacques C.; Le Gall, Jean; Sebald, Madeleine

    1963-01-01

    Sigal, Nicole (Laboratoire de Chimie Bactérienne du CNRS, Marseille, France), Jacques C. Senez, Jean Le Gall, and Madeleine Sebald. Base composition of the deoxyribonucleic acid of sulfate-reducing bacteria. J. Bacteriol. 85:1315–1318. 1963—The deoxyribonucleic acid constitution of several strains of sulfate-reducing bacteria has been analytically determined. The results of these studies show that this group of microorganisms includes at least four subgroups characterized by significantly different values of the adenine plus thymine to guanine plus cytosine ratio. The nonsporulated forms with polar flagellation, containing both cytochrome c3 and desulfoviridin, are divided into two subgroups. One includes the fresh-water, nonhalophilic strains with base ratio from 0.54 to 0.59, and the other includes the halophilic or halotolerant strains with base ratio from 0.74 to 0.77. The sporulated, peritrichous strains without cytochrome and desulfoviridin (“nigrificans” and “orientis”) are distinct from the above two types and differ from each other, having base ratios of 1.20 and 1.43, respectively. PMID:14047223

  3. The Skeletal Amino Acid Composition of the Marine Demosponge Aplysina cavernicola

    PubMed Central

    Ueberlein, Susanne; Machill, Susanne; Niemann, Hendrik; Proksch, Peter; Brunner, Eike

    2014-01-01

    It has been discovered during the past few years that demosponges of the order Verongida such as Aplysina cavernicola exhibit chitin-based skeletons. Verongida sponges are well known to produce bioactive brominated tyrosine derivatives. We could recently demonstrate that brominated compounds do not exclusively occur in the cellular matrix but also in the skeletons of the marine sponges Aplysina cavernicola and Ianthella basta. Our measurements imply that these yet unknown compounds are strongly, possibly covalently bound to the sponge skeletons. In the present work, we determined the skeletal amino acid composition of the demosponge A. cavernicola especially with respect to the presence of halogenated amino acids. The investigations of the skeletons before and after MeOH extraction confirmed that only a small amount of the brominated skeleton-bound compounds dissolves in MeOH. The main part of the brominated compounds is strongly attached to the skeletons but can be extracted for example by using Ba(OH)2. Various halogenated tyrosine derivatives were identified by GC-MS and LC-MS in these Ba(OH)2 extracts of the skeletons. PMID:25110918

  4. Fluorine profiles in human enamel after in vitro treatment with dentifrices of different compositions and acidities.

    PubMed

    Petersson, L G; Lodding, A; Hakeberg, M; Koch, G

    1989-01-01

    Fluorine uptake has been measured in human enamel after in vitro treatment with slurries of dentifrices of different compositions and acidities. Secondary ion mass spectrometry (SIMS) was used to determine the quantitative in-depth distribution profiles of fluorine. Five dentifrices were examined: ACTA (pH 5.5) with 250, 1000 and 1500 ppm F as NaF; Colgate (pH 7) with 1000 ppm F as MFP and 400 ppm F as NaF; and Pepsodent (pH 7) with 1000 ppm F as MFP. The results establish that acidulated dentifrice with low F concentration gives about the same fluorine uptake in near-surface enamel as do pH 7 dentifrices with higher F contents. In addition, at depths greater than ca 3 microns, the low F acid dentifrice in fact introduces considerably higher levels of fluorine, and yields at least three times deeper penetration, than do the non-acidulated toothpastes. The study illustrates the advantages of enhanced fluorine uptake, and thereby improved cariostatic effect, by using acidulated dentifrices even at relatively low fluoride concentration.

  5. Oil Content, Fatty Acid Composition and Distributions of Vitamin-E-Active Compounds of Some Fruit Seed Oils

    PubMed Central

    Matthäus, Bertrand; Özcan, Mehmet Musa

    2015-01-01

    Oil content, fatty acid composition and the distribution of vitamin-E-active compounds of selected Turkish seeds that are typically by-products of the food processing industries (linseed, apricot, pear, fennel, peanut, apple, cotton, quince and chufa), were determined. The oil content of the samples ranged from 16.9 to 53.4 g/100 g. The dominating fatty acids were oleic acid (apricot seed oil, peanut oil, and chufa seed oil) in the range of 52.5 to 68.4 g/100 g and linoleic acid (pear seed oil, apple seed oil, cottonseed oil and quince seed oil) with 48.1 to 56.3 g/100 g, while in linseed oil mainly α-linolenic acid (53.2 g/100 g) and in fennel seed oil mainly 18:1 fatty acids (80.5 g/100 g) with petroselinic acid predominating. The total content of vitamin-E-active compounds ranged from 20.1 (fennel seed oil) to 96 mg/100 g (apple seed oil). The predominant isomers were established as α- and γ-tocopherol. PMID:26785341

  6. Oil Content, Fatty Acid Composition and Distributions of Vitamin-E-Active Compounds of Some Fruit Seed Oils.

    PubMed

    Matthäus, Bertrand; Musazcan Özcan, Mehmet

    2015-01-01

    Oil content, fatty acid composition and the distribution of vitamin-E-active compounds of selected Turkish seeds that are typically by-products of the food processing industries (linseed, apricot, pear, fennel, peanut, apple, cotton, quince and chufa), were determined. The oil content of the samples ranged from 16.9 to 53.4 g/100 g. The dominating fatty acids were oleic acid (apricot seed oil, peanut oil, and chufa seed oil) in the range of 52.5 to 68.4 g/100 g and linoleic acid (pear seed oil, apple seed oil, cottonseed oil and quince seed oil) with 48.1 to 56.3 g/100 g, while in linseed oil mainly α-linolenic acid (53.2 g/100 g) and in fennel seed oil mainly 18:1 fatty acids (80.5 g/100 g) with petroselinic acid predominating. The total content of vitamin-E-active compounds ranged from 20.1 (fennel seed oil) to 96 mg/100 g (apple seed oil). The predominant isomers were established as α- and γ-tocopherol. PMID:26785341

  7. 4-Mercaptophenylboronic acid functionalized graphene oxide composites: Preparation, characterization and selective enrichment of glycopeptides.

    PubMed

    Jiang, Bo; Qu, Yanyan; Zhang, Lihua; Liang, Zhen; Zhang, Yukui

    2016-03-17

    Selective enrichment and isolation of glycopeptides from complex biological samples was indispensable for mass spectrometry (MS)-based glycoproteomics, however, it remained a great challenge due to the low abundance of glycoproteins and the ion suppression of non-glycopeptides. In this work, 4-mercaptophenylboronic acid functionalized graphene oxide composites were synthesized via loading gold nanoparticles on polyethylenimine modified graphene oxide surface, followed by 4-mercaptophenylboronic acid immobilization by the formation of Au-S bonding (denoted as GO/PEI/Au/4-MPB composites). The composites showed highly specific and efficient capture of glycopeptides due to their excellent hydrophilicity and abundant boronic acid groups. The composites could selectively capture the glycopeptides from the mixture of glycopeptides and nonglycopeptides, even when the amounts of non-glycopeptides were 100 times more than glycopeptides. Compared with commercial meta-amino phenylboronic acid agarose, the composites showed better selectivity when the sample was decreased to 10 ng. These results clearly verified that the GO/PEI/Au/4-MPB composites might be a promising material for glycoproteomics analysis.

  8. Chia (Salvia hispanica L.) seed as an n-3 fatty acid source for finishing pigs: effects on fatty acid composition and fat stability of the meat and internal fat, growth performance, and meat sensory characteristics.

    PubMed

    Coates, W; Ayerza, R

    2009-11-01

    Coronary heart disease is caused by arteriosclerosis, which is triggered by an unbalanced fatty acid profile in the body. Today, Western diets are typically low in n-3 fatty acids and high in SFA and n-6 fatty acids; consequently, healthier foods are needed. Chia seed (Salvia hispanica L.), which contains the greatest known plant source of n-3 alpha-linolenic acid, was fed at the rate of 10 and 20% to finishing pigs, with the goal to determine if this new crop would increase the n-3 content of the meat as has been reported for other n-3 fatty acid-rich crops. The effects of chia on fatty acid composition of the meat, internal fats, growth performance, and meat sensory characteristics were determined. Productive performance was unaffected by dietary treatment. Chia seed modified the fatty acid composition of the meat fat, but not of the internal fat. Significantly (P < 0.05) less palmitic, stearic, and arachidic acids were found with both chia treatments. This is different than trials in which flaxseed, another plant based source of omega-3 fatty acid, has been fed. Alpha-linolenic acid content increased with increasing chia content of the diet; however, only the effect of the 20% ration was significantly (P < 0.05) different from that of the control. Chia seed increased panel member preferences for aroma and flavor of the meat. This study tends to show that chia seems to be a viable feed that can produce healthier pork for human consumption.

  9. Characterization of Fatty Acid Composition in Bone Marrow Fluid From Postmenopausal Women: Modification After Hip Fracture.

    PubMed

    Miranda, Melissa; Pino, Ana María; Fuenzalida, Karen; Rosen, Clifford J; Seitz, Germán; Rodríguez, J Pablo

    2016-10-01

    Bone marrow adipose tissue (BMAT) is associated with low bone mass, although the functional consequences for skeletal maintenance of increased BMAT are currently unclear. BMAT might have a role in systemic energy metabolism, and could be an energy source as well as an endocrine organ for neighboring bone cells, releasing cytokines, adipokines and free fatty acids into the bone marrow microenvironment. The aim of the present report was to compare the fatty acid composition in the bone marrow supernatant fluid (BMSF) and blood plasma of postmenopausal women women (65-80 years old). BMSF was obtained after spinning the aspirated bone marrow samples; donors were classified as control, osteopenic or osteoporotic after dual-energy X-ray absorptiometry. Total lipids from human bone marrow fluid and plasma were extracted, converted to the corresponding methyl esters, and finally analyzed by a gas chromatographer coupled with a mass spectrometer. Results showed that fatty acid composition in BMSF was dynamic and distinct from blood plasma, implying significance in the locally produced lipids. The fatty acid composition in the BMSF was enriched in saturated fatty acid and decreased in unsaturated fatty acids as compared to blood plasma, but this relationship switched in women who suffered a hip fracture. On the other hand, there was no relationship between BMSF and bone mineral density. In conclusion, lipid composition of BMSF is distinct from the circulatory compartment, most likely reflecting the energy needs of the marrow compartment. J. Cell. Biochem. 117: 2370-2376, 2016. © 2016 Wiley Periodicals, Inc. PMID:27416518

  10. Characterization of Fatty Acid Composition in Bone Marrow Fluid From Postmenopausal Women: Modification After Hip Fracture.

    PubMed

    Miranda, Melissa; Pino, Ana María; Fuenzalida, Karen; Rosen, Clifford J; Seitz, Germán; Rodríguez, J Pablo

    2016-10-01

    Bone marrow adipose tissue (BMAT) is associated with low bone mass, although the functional consequences for skeletal maintenance of increased BMAT are currently unclear. BMAT might have a role in systemic energy metabolism, and could be an energy source as well as an endocrine organ for neighboring bone cells, releasing cytokines, adipokines and free fatty acids into the bone marrow microenvironment. The aim of the present report was to compare the fatty acid composition in the bone marrow supernatant fluid (BMSF) and blood plasma of postmenopausal women women (65-80 years old). BMSF was obtained after spinning the aspirated bone marrow samples; donors were classified as control, osteopenic or osteoporotic after dual-energy X-ray absorptiometry. Total lipids from human bone marrow fluid and plasma were extracted, converted to the corresponding methyl esters, and finally analyzed by a gas chromatographer coupled with a mass spectrometer. Results showed that fatty acid composition in BMSF was dynamic and distinct from blood plasma, implying significance in the locally produced lipids. The fatty acid composition in the BMSF was enriched in saturated fatty acid and decreased in unsaturated fatty acids as compared to blood plasma, but this relationship switched in women who suffered a hip fracture. On the other hand, there was no relationship between BMSF and bone mineral density. In conclusion, lipid composition of BMSF is distinct from the circulatory compartment, most likely reflecting the energy needs of the marrow compartment. J. Cell. Biochem. 117: 2370-2376, 2016. © 2016 Wiley Periodicals, Inc.

  11. Effect of DNA polymorphisms related to fatty acid composition in adipose tissue of Holstein cattle.

    PubMed

    Narukami, Takahiro; Sasazaki, Shinji; Oyama, Kenji; Nogi, Takuya; Taniguchi, Masaaki; Mannen, Hideyuki

    2011-06-01

    Fatty acid composition of adipose tissue has been recognized as an important carcass trait because of its relationship with eating quality such as favorable beef flavor and tenderness. Therefore, we investigated the effects of genetic polymorphisms of liver X receptor, alpha (LXR), stearoyl-CoA desaturase (SCD), Fatty acid synthase (FASN), and Fatty acid binding protein 4 (FABP4) on fatty acid composition in intramuscular fat tissue of Holstein steers. The major allele frequencies were 0.705 in SCD, 0.518 in FABP4, 0.888 in FASN, and 0.984 in LXR. Genotyping of SCD showed significant effect on C14:0, C14:1, C18:0 and saturated fatty acid (P < 0.05). In addition, the result suggested that SCD genotype possibly had effect on composition of C18:1 and monounsaturated fatty acid. Genotype of FABP4 had significant effect on composition of C16:0. Effect of LXR genotypes could not be analyze because of extremely biased genotype frequencies. Our results suggest that genotypes of SCD and FABP4 may in part affect meat quality in Holstein.

  12. Fatty acid composition of birds and game hunted by the Eastern James Bay Cree people of Québec

    PubMed Central

    Proust, Francoise; Johnson-Down, Louise; Berthiaume, Line; Greffard, Karine; Julien, Pierre; Robinson, Elizabeth; Lucas, Michel; Dewailly, Éric

    2016-01-01

    Background Indigenous peoples have traditionally relied on foods hunted and gathered from their immediate environment. The Eastern James Bay Cree people consume wild game and birds, and these are believed to provide health as well as cultural benefits. Objective To determine the fatty acid (FA) composition of traditional game and bird meats hunted in the Eastern James Bay area. Design Harvested traditional game and birds were analysed for FA composition. A total of 52 samples from six wildlife species were collected in the areas of Chisasibi, Waswanipi and Mistissini, of which 35 were from birds (white partridge and Canada goose) and 17 were from land animals (beaver, moose, caribou and black bear). Results Alpha-linolenic acid (ALA) was the most common n-3 polyunsaturated fatty acid (PUFA) in all samples except for the black bear flesh, in which it was docosapentaenoic acid (DPAn-3). In white partridge, beaver and caribou flesh, PUFAs (mainly n-6) were the most common category of fats while in goose, moose and black bear flesh, monounsaturated fatty acids (MUFAs) predominated. In all species, saturated fatty acids (SFAs) were the second most important FAs. It would appear that in the land animals and birds that were analysed, the SFA content was lower and the PUFA content was higher than store-bought meats giving them a more heart-healthy profile. Conclusions These results showed that the FA composition of game species consumed by the James Bay Cree population is consistent with a beneficial diet and that traditional foods should continue to be promoted among the Cree people to provide better physical health as well as social and spiritual benefits. PMID:27495903

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

    NASA Technical Reports Server (NTRS)

    Miller, S. L.; Schlesinger, G.

    1993-01-01

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

  14. Quantitative Determination of Citric and Ascorbic Acid in Powdered Drink Mixes

    ERIC Educational Resources Information Center

    Sigmann, Samuella B.; Wheeler, Dale E.

    2004-01-01

    A procedure by which the reactions are used to quantitatively determine the amount of total acid, the amount of total ascorbic acid and the amount of citric acid in a given sample of powdered drink mix, are described. A safe, reliable and low-cost quantitative method to analyze consumer product for acid content is provided.

  15. Additive Manufacturing and Characterization of Polylactic Acid (PLA) Composites Containing Metal Reinforcements

    NASA Technical Reports Server (NTRS)

    Kuentz, Lily; Salem, Anton; Singh, M.; Halbig, M. C.; Salem, J. A.

    2016-01-01

    Additive manufacturing of polymeric systems using 3D printing has become quite popular recently due to rapid growth and availability of low cost and open source 3D printers. Two widely used 3D printing filaments are based on polylactic acid (PLA) and acrylonitrile butadiene styrene (ABS) systems. PLA is much more environmentally friendly in comparison to ABS since it is made from renewable resources such as corn, sugarcane, and other starches as precursors. Recently, polylactic acid-based metal powder containing composite filaments have emerged which could be utilized for multifunctional applications. The composite filaments have higher density than pure PLA, and the majority of the materials volume is made up of polylactic acid. In order to utilize functionalities of composite filaments, printing behavior and properties of 3-D printed composites need to be characterized and compared with the pure PLA materials. In this study, pure PLA and composite specimens with different metallic reinforcements (Copper, Bronze, Tungsten, Iron, etc) were 3D printed at various layer heights and resulting microstructures and properties were characterized. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) behavior of filaments with different reinforcements were studied. The microscopy results show an increase in porosity between 3-D printed regular PLA and the metal composite PLA samples, which could produce weaker mechanical properties in the metal composite materials. Tensile strength and fracture toughness behavior of specimens as a function of print layer height will be presented.

  16. Cd(II) Sorption on Montmorillonite-Humic acid-Bacteria Composites

    PubMed Central

    Du, Huihui; Chen, Wenli; Cai, Peng; Rong, Xingmin; Dai, Ke; Peacock, Caroline L.; Huang, Qiaoyun

    2016-01-01

    Soil components (e.g., clays, bacteria and humic substances) are known to produce mineral-organic composites in natural systems. Herein, batch sorption isotherms, isothermal titration calorimetry (ITC), and Cd K-edge EXAFS spectroscopy were applied to investigate the binding characteristics of Cd on montmorillonite(Mont)-humic acid(HA)-bacteria composites. Additive sorption and non-additive Cd(II) sorption behaviour is observed for the binary Mont-bacteria and ternary Mont-HA-bacteria composite, respectively. Specifically, in the ternary composite, the coexistence of HA and bacteria inhibits Cd adsorption, suggesting a “blocking effect” between humic acid and bacterial cells. Large positive entropies (68.1 ~ 114.4 J/mol/K), and linear combination fitting of the EXAFS spectra for Cd adsorbed onto Mont-bacteria and Mont-HA-bacteria composites, demonstrate that Cd is mostly bound to bacterial surface functional groups by forming inner-sphere complexes. All our results together support the assertion that there is a degree of site masking in the ternary clay mineral-humic acid-bacteria composite. Because of this, in the ternary composite, Cd preferentially binds to the higher affinity components-i.e., the bacteria. PMID:26792640

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

    USGS Publications Warehouse

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

    2009-01-01

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

  18. Surface of Lactic Acid Bacteria: Relationships between Chemical Composition and Physicochemical Properties

    PubMed Central

    Boonaert, Christophe J. P.; Rouxhet, Paul G.

    2000-01-01

    The surface chemical composition and physicochemical properties (hydrophobicity and zeta potential) of two lactic acid bacteria, Lactococcus lactis subsp. lactis bv. diacetilactis and Lactobacillus helveticus, have been investigated using cells harvested in exponential or stationary growth phase. The surface composition determined by X-ray photoelectron spectroscopy (XPS) was converted into a molecular composition in terms of proteins, polysaccharides, and hydrocarbonlike compounds. The concentration of the last was always below 15% (wt/wt), which is related to the hydrophilic character revealed by water contact angles of less than 30°. The surfaces of L. lactis cells had a polysaccharide concentration about twice that of proteins. The S-layer of L. helveticus was either interrupted or crossed by polysaccharide-rich compounds; the concentration of the latter was higher in the stationary growth phase than in the exponential growth phase. Further progress was made in the interpretation of XPS data in terms of chemical functions by showing that the oxygen component at 531.2 eV contains a contribution of phosphate in addition to the main contribution of the peptide link. The isoelectric points were around 2 and 3, and the electrophoretic mobilities above pH 5 (ionic strength, 1 mM) were about −3.0 × 10−8 and −0.6 × 10−8 m2 s−1 V−1 for L. lactis and L. helveticus, respectively. The electrokinetic properties of the latter reveal the influence of carboxyl groups, while the difference between the two strains is related to a difference between N/P surface concentration ratios, reflecting the relative exposure of proteins and phosphate groups at the surface. PMID:10831437

  19. Solar thermal charging properties of graphene oxide embedded myristic acid composites phase change material

    NASA Astrophysics Data System (ADS)

    Yadav, Apurv; Barman, Bidyut; Kumar, Vivek; Kardam, Abhishek; Narayanan, S. Shankara; Verma, Abhishek; Madhwal, Devinder; Shukla, Prashant; Jain, V. K.

    2016-05-01

    The present paper reports the heat transfer characteristics of graphene oxide (GO) embedded myristic acid based phase change material (GO-PCM) composites. By varying concentrations of GO (0.1-0.5 wt%), different GO-PCM composites were preapred. Two different experimental setups were used for investigating the heat transfer characteristics of the prepared GO-PCM composites during the melting and solidification processes: (i) conventional heating and (ii) solar illumination. The experimental observations indicated a higher heat transfer rate in the GO-PCM composites as compared to pristine PCM for both experimental setups. From the experimental results of conventional heating setup, it was observed that the melting and solidification rate for GO-PCM composites, at 0.5 wt% of GO, increased by 48% and 70%, respectively in comparison to pristine PCM. The experimental results using solar illumination setup demonstrated an ultrafast heating rate for GO-PCM composites than the conventional heating based approach.

  20. Biocompatibility and characterization of polylactic acid/styrene-ethylene-butylene-styrene composites.

    PubMed

    Tsou, Chi-Hui; Kao, Bo-Jyue; Yang, Ming-Chien; Suen, Maw-Cherng; Lee, Yi-Hsuan; Chen, Jui-Chin; Yao, Wei-Hua; Lin, Shang-Ming; Tsou, Chih-Yuan; Huang, Shu-Hsien; De Guzman, Manuel; Hung, Wei-Song

    2015-01-01

    Polylactic acid (PLA)/styrene-ethylene-butylene-styrene (SEBS) composites were prepared by melt blending. Differential scanning calorimetry (DSC) and wide angle X-ray diffraction (WXRD) were used to characterize PLA and PLA/SEBS composites in terms of their melting behavior and crystallization. Curves from thermal gravimetric analysis (TGA) illustrated that thermostability increased with SEBS content. Further morphological analysis of PLA/SEBS composites revealed that SEBS molecules were not miscible with PLA molecules in PLA/SEBS composites. The tensile testing for PLA and PLA/SEBS composites showed that the elongation at the break was enhanced, but tensile strength decreased with increasing SEBS content. L929 fibroblast cells were chosen to assess the cytocompatibility; the cell growth of PLA was found to decrease with increasing SEBS content. This study proposes possible reasons for these properties of PLA/SEBS composites.

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

    PubMed

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

    2013-10-15

    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

  2. Determination of thioglycolic acid in cosmetics by capillary electrophoresis.

    PubMed

    Xie, Na; Ding, Xiaojing; Wang, Xinyu; Wang, Ping; Zhao, Shan; Wang, Zhi

    2014-01-01

    A new and simple method for the accurate determination of thioglycolic acid (TGA) in cosmetics was developed using capillary electrophoresis (CE) with diode array detection at 236nm. The CE separation was performed on an uncoated fused silica capillary with a separation buffer solution containing 300mmolL(-1) tri-sodium phosphate and 0.5mmolL(-1) cetyltrimethylammonium bromide at a voltage of -5kV. Both the intra- and inter-day precisions of the method were 1.4%. The calibration curve between the corrected peak areas and the concentrations of the TGA was linear within the concentration range of 0.006-1.0mgmL(-1) with a correlation coefficient (r) of 0.9998. The limit of detection and limit of quantitation were 0.002mgmL(-1) (S/N=3) and 0.006mgmL(-1) (S/N=10), respectively. The average recoveries at the spiked levels of 0.125, 0.250 and 0.500mgmL(-1) were 96.9%, 102.3% and 94.0% with the relative standard derivations of 2.1%, 3.9% and 2.2%, respectively. The method was cross-validated by both high performance liquid chromatographic and ion chromatographic method. Eighty-five commercial depilatory creams and hair-treatment products were analyzed with satisfactory results.

  3. Physical activity as a determinant of fecal bile acid levels

    PubMed Central

    Wertheim, Betsy C.; Martínez, María Elena; Ashbeck, Erin L.; Roe, Denise J.; Jacobs, Elizabeth T.; Alberts, David S.; Thompson, Patricia A.

    2009-01-01

    Physical activity is protective against colon cancer, whereas colonic bile acid exposure is a suspected risk factor. While likely related, the association between physical activity and bile acid levels has not been well studied. Furthermore, the effect of triglycerides, which are known to modify bile acid levels, on this relationship has not been investigated. We conducted a cross-sectional analysis of baseline fecal bile acid levels for 735 colorectal adenoma formers obtained from participants in a phase III ursodeoxycholic acid chemoprevention trial. Compared to the lowest quartile of recreational physical activity duration, the highest quartile was associated with a 17% lower fecal bile acid concentration, adjusted for age, sex, dietary fiber intake, and body mass index (P = 0.042). Furthermore, consistent with a previously established relationship between serum triglyceride levels and bile acid metabolism, we stratified by triglyceride level and observed a 34% lower fecal bile acid concentration (highest versus lowest quartiles of physical activity) in individuals with low triglycerides (< 136 mg/dL; P = 0.002). In contrast, no association between physical activity and fecal bile acid concentration was observed for subjects with high triglycerides (≥ 136 mg/dL). Our results suggest that the biological mechanism responsible for the protective effect of physical activity on the incidence of colon cancer may be partially mediated by decreasing colonic bile acid exposure. However, this effect may be limited to individuals with lower triglyceride levels. PMID:19383885

  4. Stable carbon isotopic compositions of low-molecular-weight dicarboxylic acids, oxocarboxylic acids, α-dicarbonyls, and fatty acids: implications for atmospheric processing of organic aerosols

    NASA Astrophysics Data System (ADS)

    Zhang, Y.; Kawamura, K.; Cao, F.; Lee, M.

    2015-12-01

    Stable carbon isotopic compositions (δ13C) were measured for 23 individual organic species including 9 dicarboxylic acids, 7 oxocarboxylic acids, 1 tricarboxylic acid, 2 α-dicarbonyls and 4 fatty acids in the aerosols from Gosan background site in East Asia. δ13C of particle-phase glyoxal and methylglyoxal are significantly higher than those previously reported for isoprene and other precursors, associated with isotope fractionation during atmospheric oxidation. 13C is consistently more enriched for oxalic acid (C2), glyoxylic acid, pyruvic acid, glyoxal and methylglyoxal compared to other organic compounds identified, which can be explained by the kinetic isotope effects during aqueous-phase processing and the subsequent gas-particle partitioning after clouds or wet aerosols evaporation δ13C of C2 is positively correlated with C2 and organic carbon ratio, indicating that a photochemical production of C2 is more pronounced than its degradation process during long-range transport. The 13C results also suggest that aqueous-phase oxidation of glyoxal and methylglyoxal is major formation process of oxalic acid production via the major intermediates glyoxylic acid and pyruvic acid. This study provides evidence that organic aerosols are intensively photo-chemically aged in this region.

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

    PubMed

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

    2015-04-15

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

  6. Solid Sulfonic Acid Catalysts Based on Porous Carbons and Carbon-Silica Composites

    NASA Astrophysics Data System (ADS)

    Tian, Xiao Ning; Luo, Lijuan; Jiang, Zhongqing; Zhao, X. S.

    Mesoporous carbons prepared using a templating method under different carbonization temperatures are sulfonated with concentrated H2SO4. Without the moving of silica template carbon-silica composites were prepared, which can maintain the pore structure well during sulfonation reaction process. The resultant samples are characterized using nitrogen adsorption, transmission electron microscope, field-emission scanning electron microscope, X-ray diffraction, X-ray photoelectron spectroscopy, and elemental analysis techniques. The catalytic performances of the sulfonated carbons and composites are evaluated by esterification reaction of methanol with acetic acid. The results show that a low-temperature carbonization process is favorable for improving the reaction conversion of acetic acid. In addition, the sulfonated carbon-silica composites show a higher acetic acid conversion than the sulfonated mesoporous carbons.

  7. Taking into Account the Instrumental Function in Spectrophotometric Determination of the Composition of a Medium

    NASA Astrophysics Data System (ADS)

    Liudchik, A. M.

    2015-11-01

    A procedure is proposed for determining the composition of a medium by photometry of the radiation passing through it when the recording instrument has insufficient spectral resolution. The effectiveness of the procedure is illustrated using model examples. A correlation is determined between uncertainties in the signal measurements and the resulting errors in estimates of the composition of the medium.

  8. Effects of plant species, stage of maturity, and level of formic acid addition on lipolysis, lipid content, and fatty acid composition during ensiling.

    PubMed

    Koivunen, E; Jaakkola, S; Heikkilä, T; Lampi, A-M; Halmemies-Beauchet-Filleau, A; Lee, M R F; Winters, A L; Shingfield, K J; Vanhatalo, A

    2015-09-01

    Forage type and management influences the nutritional quality and fatty acid composition of ruminant milk. Replacing grass silage with red clover (RC; L.) silage increases milk fat 18:3-3 concentration. Red clover has a higher polyphenol oxidase (PPO) activity compared with grasses, which has been suggested to decrease lipolysis and . The present study characterized the abundance and fatty acid composition of esterified lipid and NEFA before and after ensiling of grass and RC to investigate the influence of forage species, growth stage, and extent of fermentation on lipolysis. A randomized block design with a 2 × 3 × 4 factorial arrangement of treatments was used. Treatments comprised RC or a mixture of timothy ( L.) and meadow fescue ( Huds.) harvested at 3 growth stages and treated with 4 levels of formic acid (0, 2, 4, and 6 L/t). Lipid in silages treated with 0 or 6 L/t formic acid were extracted and separated into 4 fractions by TLC. Total PPO activity in fresh herbage and the content of soluble bound phenols in all silages were determined. Concentrations of 18:3-3 and total fatty acids (TFA) were higher ( < 0.001) for RC than for grass. For both forage species, 18:3-3 and TFA content decreased linearly ( < 0.001) with advancing growth stage, with the highest abundance at the vegetative stage. Most of lipid in fresh RC and grass herbage (97%) was esterified, whereas NEFA accounted for 71% of TFA in both silages. Ensiling resulted in marginal increases in TFA content and the amounts of individual fatty acids compared with fresh herbages. Herbage total PPO activity was higher ( < 0.001) for RC than grass (11 vs. 0.11 μkatal/g leaf fresh weight). Net lipolysis during ensiling was extensive for both forage species (660 to 759 g/kg fatty acid for grass and 563 to 737 g/kg fatty acid for RC). Formic acid application (0 vs. 6 L/t) resulted in a marked decrease ( = 0.026) in net lipolysis during the ensiling of RC, whereas the opposite was true ( = 0.026) for grass

  9. Fatty Acid Composition of Novel Host Jack Pine Do Not Prevent Host Acceptance and Colonization by the Invasive Mountain Pine Beetle and Its Symbiotic Fungus.

    PubMed

    Ishangulyyeva, Guncha; Najar, Ahmed; Curtis, Jonathan M; Erbilgin, Nadir

    2016-01-01

    Fatty acids are major components of plant lipids and can affect growth and development of insect herbivores. Despite a large literature examining the roles of fatty acids in conifers, relatively few studies have tested the effects of fatty acids on insect herbivores and their microbial symbionts. Particularly, whether fatty acids can affect the suitability of conifers for insect herbivores has never been studied before. Thus, we evaluated if composition of fatty acids impede or facilitate colonization of jack pine (Pinus banksiana) by the invasive mountain pine beetle (Dendroctonus ponderosae) and its symbiotic fungus (Grosmannia clavigera). This is the first study to examine the effects of tree fatty acids on any bark beetle species and its symbiotic fungus. In a novel bioassay, we found that plant tissues (hosts and non-host) amended with synthetic fatty acids at concentrations representative of jack pine were compatible with beetle larvae. Likewise, G. clavigera grew in media amended with lipid fractions or synthetic fatty acids at concentrations present in jack pine. In contrast, fatty acids and lipid composition of a non-host were not suitable for the beetle larvae or the fungus. Apparently, concentrations of individual, rather than total, fatty acids determined the suitability of jack pine. Furthermore, sampling of host and non-host tree species across Canada demonstrated that the composition of jack pine fatty acids was similar to the different populations of beetle's historical hosts. These results demonstrate that fatty acids composition compatible with insect herbivores and their microbial symbionts can be important factor defining host suitability to invasive insects. PMID:27583820

  10. Fatty Acid Composition of Novel Host Jack Pine Do Not Prevent Host Acceptance and Colonization by the Invasive Mountain Pine Beetle and Its Symbiotic Fungus

    PubMed Central

    Ishangulyyeva, Guncha; Najar, Ahmed; Curtis, Jonathan M.

    2016-01-01

    Fatty acids are major components of plant lipids and can affect growth and development of insect herbivores. Despite a large literature examining the roles of fatty acids in conifers, relatively few studies have tested the effects of fatty acids on insect herbivores and their microbial symbionts. Particularly, whether fatty acids can affect the suitability of conifers for insect herbivores has never been studied before. Thus, we evaluated if composition of fatty acids impede or facilitate colonization of jack pine (Pinus banksiana) by the invasive mountain pine beetle (Dendroctonus ponderosae) and its symbiotic fungus (Grosmannia clavigera). This is the first study to examine the effects of tree fatty acids on any bark beetle species and its symbiotic fungus. In a novel bioassay, we found that plant tissues (hosts and non-host) amended with synthetic fatty acids at concentrations representative of jack pine were compatible with beetle larvae. Likewise, G. clavigera grew in media amended with lipid fractions or synthetic fatty acids at concentrations present in jack pine. In contrast, fatty acids and lipid composition of a non-host were not suitable for the beetle larvae or the fungus. Apparently, concentrations of individual, rather than total, fatty acids determined the suitability of jack pine. Furthermore, sampling of host and non-host tree species across Canada demonstrated that the composition of jack pine fatty acids was similar to the different populations of beetle’s historical hosts. These results demonstrate that fatty acids composition compatible with insect herbivores and their microbial symbionts can be important factor defining host suitability to invasive insects. PMID:27583820

  11. Fatty Acid Composition of Novel Host Jack Pine Do Not Prevent Host Acceptance and Colonization by the Invasive Mountain Pine Beetle and Its Symbiotic Fungus.

    PubMed

    Ishangulyyeva, Guncha; Najar, Ahmed; Curtis, Jonathan M; Erbilgin, Nadir

    2016-01-01

    Fatty acids are major components of plant lipids and can affect growth and development of insect herbivores. Despite a large literature examining the roles of fatty acids in conifers, relatively few studies have tested the effects of fatty acids on insect herbivores and their microbial symbionts. Particularly, whether fatty acids can affect the suitability of conifers for insect herbivores has never been studied before. Thus, we evaluated if composition of fatty acids impede or facilitate colonization of jack pine (Pinus banksiana) by the invasive mountain pine beetle (Dendroctonus ponderosae) and its symbiotic fungus (Grosmannia clavigera). This is the first study to examine the effects of tree fatty acids on any bark beetle species and its symbiotic fungus. In a novel bioassay, we found that plant tissues (hosts and non-host) amended with synthetic fatty acids at concentrations representative of jack pine were compatible with beetle larvae. Likewise, G. clavigera grew in media amended with lipid fractions or synthetic fatty acids at concentrations present in jack pine. In contrast, fatty acids and lipid composition of a non-host were not suitable for the beetle larvae or the fungus. Apparently, concentrations of individual, rather than total, fatty acids determined the suitability of jack pine. Furthermore, sampling of host and non-host tree species across Canada demonstrated that the composition of jack pine fatty acids was similar to the different populations of beetle's historical hosts. These results demonstrate that fatty acids composition compatible with insect herbivores and their microbial symbionts can be important factor defining host suitability to invasive insects.

  12. Simultaneous Determination of Methanol, Ethanol and Formic Acid in Serum and Urine by Headspace GC-FID.

    PubMed

    Bursová, Miroslava; Hložek, Tomáš; Čabala, Radomír

    2015-01-01

    A simple, cost-effective headspace gas chromatography (GC) method coupled with GC with flame ionization detection for simultaneous determination of methanol, ethanol and formic acid was developed and validated for clinical and toxicological purposes. Formic acid was derivatized with an excess of isopropanol under acidic conditions to its volatile isopropyl ester while methanol and ethanol remained unchanged. The entire sample preparation procedure is complete within 6 min. The design of the experiment (the face-centered central composite design) was used for finding the optimal conditions for derivatization, headspace sampling and chromatographic separation. The calibration dependences of the method were quadratic in the range from 50 to 5,000 mg/L, with adequate accuracy (89.0-114.4%) and precision (<12%) in the serum. The new method was successfully used for determination of selected analytes in serum samples of intoxicated patients from among those affected by massive methanol poisonings in the Czech Republic in 2012.

  13. Molecular species composition of plant cardiolipin determined by liquid chromatography mass spectrometry.

    PubMed

    Zhou, Yonghong; Peisker, Helga; Dörmann, Peter

    2016-07-01

    Cardiolipin (CL), an anionic phospholipid of the inner mitochondrial membrane, provides essential functions for stabilizing respiratory complexes and is involved in mitochondrial morphogenesis and programmed cell death in animals. The role of CL and its metabolism in plants are less well understood. The measurement of CL in plants, including its molecular species composition, is hampered by the fact that CL is of extremely low abundance, and that plants contain large amounts of interfering compounds including galactolipids, neutral lipids, and pigments. We used solid phase extraction by anion exchange chromatography to purify CL from crude plant lipid extracts. LC/MS was used to determine the content and molecular species composition of CL. Thus, up to 23 different molecular species of CL were detected in different plant species, including Arabidopsis, mung bean, spinach, barley, and tobacco. Similar to animals, plant CL is dominated by highly unsaturated species, mostly containing linoleic and linolenic acid. During phosphate deprivation or exposure to an extended dark period, the amount of CL decreased in Arabidopsis, accompanied with an increased degree in unsaturation. The mechanism of CL remodeling during stress, and the function of highly unsaturated CL molecular species, remains to be defined. PMID:27179363

  14. 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

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

    2010-01-01

    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. PMID:20048057

  15. Influence of fatty acid precursors, including food preservatives, on the growth and fatty acid composition of Listeria monocytogenes at 37 and 10degreesC.

    PubMed

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

    2010-03-01

    Listeria monocytogenes is a food-borne pathogen that grows at refrigeration temperatures and increases its content of anteiso-C(15:0) 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 degrees C and 10 degrees 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, C(4), C(5), and C(6) branched-chain carboxylic acid, and C(3) and C(4) 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.

  16. Gallic Acid: Review of the Methods of Determination and Quantification.

    PubMed

    Fernandes, Felipe Hugo Alencar; Salgado, Hérida Regina Nunes

    2016-05-01

    Gallic acid (3,4,5 trihydroxybenzoic acid) is a secondary metabolite present in most plants. This metabolite is known to exhibit a range of bioactivities including antioxidant, antimicrobial, anti-inflammatory, and anticancer. There are various methods to analyze gallic acid including spectrometry, chromatography, and capillary electrophoresis, among others. They have been developed to identify and quantify this active ingredient in most biological matrices. The aim of this article is to review the available information on analytical methods for gallic acid, as well as presenting the advantages and limitations of each technique.

  17. Determination of the triglyceride composition of avocado oil by high-performance liquid chromatography using a light-scattering detector.

    PubMed

    Hierro, M T; Tomás, M C; Fernández-Martín, F; Santa-María, G

    1992-08-28

    The triglyceride composition of avocado oil was determined by high-performance liquid chromatography using a light-scattering detector. Two avocado varieties, Fuerte and Hass, were analysed, and the qualitative composition of each was found to be similar, though quantitative differences were detected. The triglyceride composition was predicted using a system of equations based on the relationship between log k' and the molecular variables equivalent carbon number, chain length and number of double bonds for each of the fatty acids in the glycerides. A total of 24 molecular species of triglycerides were identified. The chromatographic system used successfully separated the critical pairs OOO-LOS, PaPaO-LnPP and PaOO-LOP (O = olein; L = linolein; S = stearin; Pa = palmitolein; Ln = linolenin; P = palmitin). Detector response was found to have a linear relationship with the amount of sample injected over the injection range 10-70 micrograms.

  18. Simultaneous determination of sorbic and benzoic acids in milk products using an optimised microextraction technique followed by gas chromatography.

    PubMed

    Abedi, Abdol-Samad; Mohammadi, Abdorreza; Azadniya, Ebrahim; Mortazavian, Amir Mohammad; Khaksar, Ramin

    2014-01-01

    A rapid and reliable method for direct determination of sorbic and benzoic acids in milk products was developed by dispersive liquid-liquid microextraction (DLLME) and gas chromatography with flame ionisation detector (GC-FID). A response surface methodology (RSM) based on a central composite design (CCD) was applied for optimisation of the main variables, such as volume of extraction and dispersive solvents, pH and salt effect. The primary extraction of sorbic and benzoic acids were performed in 8 mL NaOH (0.1 M) in a closed-vessel system. Carrez solutions (potassium hexaferrocyanide and zinc acetate) were used for protein sedimentation. The best simultaneous extraction efficiency was identified using acetone and 1-octanal as dispersive and extraction solvents, respectively. For DLLME, central composite design resulted in the optimised values of microextraction parameters as follows: 475 µL of dispersive and 60 µL of extraction solvents, 2 g NaCl at pH 2.5. Under optimum conditions, the calibration curve was linear over the range 0.1-50 μg mL(-1) and the square of correlation coefficient (R(2)) was 0.9992 for sorbic acid and 0.9994 for benzoic acid. Relative standard deviation (RSD %) was 6.1% and 3.1% (n = 5) for sorbic and benzoic acids, respectively. Limits of detection were 150 ng g(-1) for sorbic acid and 140 ng g(-1) for benzoic acid and recoveries were 88% and 103.7% respectively. Good reproducibility (RSD %), short extraction time and no matrix interference were advantages of the proposed method which was successfully applied to the determination of sorbic and benzoic acids in milk products. PMID:24397823

  19. Effect of a maternal cafeteria diet on the fatty acid composition of milk and offspring red blood cells.

    PubMed

    Vithayathil, M A; Gugusheff, J R; Gibson, R A; Ong, Z Y; Muhlhausler, B S

    2016-06-01

    Previous studies have demonstrated that exposure to a maternal cafeteria diet during the lactation period alone produces detrimental effects to offspring metabolic health comparable to exposure during the entire perinatal period. The present study used a rodent model to assess the effect of a maternal cafeteria diet on the fat content and fatty acid composition of the dams' milk, and to determine the degree to which this was related to the fatty acid status of offspring on postnatal day 1 (PND1), weaning and 3 weeks post-weaning onto a standard rodent diet. As expected, omega-3 long chain polyunsaturated fatty acids (n-3 LCPUFA) content of both the milk and pup red blood cells (RBCs) was lower in the cafeteria (CAF) group on PND1. At 2 weeks post-partum, milk produced by CAF dams had a higher total fat, saturated fat and n-6 PUFA content, however these differences were modest in comparison with the differences in maternal intake between groups. Offspring suckled by CAF dams had a lower n-3 LCPUFA and n-6 PUFA status at weaning and higher trans fatty acid levels at both weaning and 6 weeks of age. These findings indicate that the fat content and fatty acid composition of the dam's milk is altered by exposure to a cafeteria diet. While it appears that the dam has a significant capacity to buffer the transfer of most dietary lipids into the milk, the trans fatty acids in particular appear to be readily transferred, resulting in persistent increases in trans fatty acid status of the offspring after weaning. The potential physiological implications of this warrants further examination. PMID:27269714

  20. Effect of a maternal cafeteria diet on the fatty acid composition of milk and offspring red blood cells.

    PubMed

    Vithayathil, M A; Gugusheff, J R; Gibson, R A; Ong, Z Y; Muhlhausler, B S

    2016-06-01

    Previous studies have demonstrated that exposure to a maternal cafeteria diet during the lactation period alone produces detrimental effects to offspring metabolic health comparable to exposure during the entire perinatal period. The present study used a rodent model to assess the effect of a maternal cafeteria diet on the fat content and fatty acid composition of the dams' milk, and to determine the degree to which this was related to the fatty acid status of offspring on postnatal day 1 (PND1), weaning and 3 weeks post-weaning onto a standard rodent diet. As expected, omega-3 long chain polyunsaturated fatty acids (n-3 LCPUFA) content of both the milk and pup red blood cells (RBCs) was lower in the cafeteria (CAF) group on PND1. At 2 weeks post-partum, milk produced by CAF dams had a higher total fat, saturated fat and n-6 PUFA content, however these differences were modest in comparison with the differences in maternal intake between groups. Offspring suckled by CAF dams had a lower n-3 LCPUFA and n-6 PUFA status at weaning and higher trans fatty acid levels at both weaning and 6 weeks of age. These findings indicate that the fat content and fatty acid composition of the dam's milk is altered by exposure to a cafeteria diet. While it appears that the dam has a significant capacity to buffer the transfer of most dietary lipids into the milk, the trans fatty acids in particular appear to be readily transferred, resulting in persistent increases in trans fatty acid status of the offspring after weaning. The potential physiological implications of this warrants further examination.

  1. Mechanical properties of a reactive endcapped polyimide based composite from polyamide acid

    SciTech Connect

    Hergenrother, P.M.; Rommel, M.L.

    1996-12-31

    The objective of this study was to characterize a composite unidirectional tape made with unsized Hercules IM7 fibers and a phenylethynyl terminated polyimide in the form of a polyamide acid. A processing study to examine the effect of cure parameters and robustness of the consolidation process was conducted and showed the versatile processing afforded by the phenylethynyl terminated polyimide. The mechanical and physical properties of laminates produced from the optimized composite cure process are presented and compared to a commercially available polyimide.

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

    SciTech Connect

    Lake, April D.; Novak, Petr; Shipkova, Petia; Aranibar, Nelly; Robertson, Donald; Reily, Michael D.; Lu, Zhenqiang; Lehman-McKeeman, Lois D.; Cherrington, Nathan J.

    2013-04-15

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

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

    PubMed

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

    2014-01-01

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

  4. Water Absorption of Jute/Polylactic Acid Composite Intended for an Interior Application and Comparison with Wood-Based Panels

    NASA Astrophysics Data System (ADS)

    Zandvliet, C.; Bandyopadhyay, N. R.; Ray, D.

    2014-04-01

    Jute/polylactic acid (PLA) composite is of special interest because it is entirely from renewable resources with high mechanical properties. Thus, it could be a more eco-friendly alternative to the conventional wood-based panels made of formaldehyde resin which is asserted to be carcinogenic. Yet the water affinity of the natural fibres and susceptibility of polylactic acid towards hydrolysis raise a question about the water resistance of such composites in service condition. In this work, the water absorption behaviour of jute/PLA composites, jute/maleated polypropylene was investigated with regard to interior applications following the standard test method in accordance to ISO 16983:2003 `Wood-based panels—determination of swelling in thickness after immersion in water' and compared to standard of wood-based panels. Untreated and treated jute/PLA composites exhibited a superior water resistance property compared to particleboard, MDF and hardboard and they are by far, below the minimum requirement of the ISO standard 16983.

  5. Soil surface acidity plays a determining role in the atmospheric-terrestrial exchange of nitrous acid.

    PubMed

    Donaldson, Melissa A; Bish, David L; Raff, Jonathan D

    2014-12-30

    Nitrous acid (HONO) is an important hydroxyl (OH) radical source that is formed on both ground and aerosol surfaces in the well-mixed boundary layer. Recent studies report the release of HONO from nonacidic soils, although it is unclear how soil that is more basic than the pKa of HONO (∼ 3) is capable of protonating soil nitrite to serve as an atmospheric HONO source. Here, we used a coated-wall flow tube and chemical ionization mass spectrometry (CIMS) to study the pH dependence of HONO uptake onto agricultural soil and model substrates under atmospherically relevant conditions (1 atm and 30% relative humidity). Experiments measuring the evolution of HONO from pH-adjusted surfaces treated with nitrite and potentiometric titrations of the substrates show, to our knowledge for the first time, that surface acidity rather than bulk aqueous pH determines HONO uptake and desorption efficiency on soil, in a process controlled by amphoteric aluminum and iron (hydr)oxides present. The results have important implications for predicting when soil nitrite, whether microbially derived or atmospherically deposited, will act as a net source or sink of atmospheric HONO. This process represents an unrecognized mechanism of HONO release from soil that will contribute to HONO emissions throughout the day.

  6. Soil surface acidity plays a determining role in the atmospheric-terrestrial exchange of nitrous acid

    PubMed Central

    Donaldson, Melissa A.; Bish, David L.; Raff, Jonathan D.

    2014-01-01

    Nitrous acid (HONO) is an important hydroxyl (OH) radical source that is formed on both ground and aerosol surfaces in the well-mixed boundary layer. Recent studies report the release of HONO from nonacidic soils, although it is unclear how soil that is more basic than the pKa of HONO (∼3) is capable of protonating soil nitrite to serve as an atmospheric HONO source. Here, we used a coated-wall flow tube and chemical ionization mass spectrometry (CIMS) to study the pH dependence of HONO uptake onto agricultural soil and model substrates under atmospherically relevant conditions (1 atm and 30% relative humidity). Experiments measuring the evolution of HONO from pH-adjusted surfaces treated with nitrite and potentiometric titrations of the substrates show, to our knowledge for the first time, that surface acidity rather than bulk aqueous pH determines HONO uptake and desorption efficiency on soil, in a process controlled by amphoteric aluminum and iron (hydr)oxides present. The results have important implications for predicting when soil nitrite, whether microbially derived or atmospherically deposited, will act as a net source or sink of atmospheric HONO. This process represents an unrecognized mechanism of HONO release from soil that will contribute to HONO emissions throughout the day. PMID:25512517

  7. Rapid determination of nonaromatic organic acids in honey by capillary zone electrophoresis with direct ultraviolet detection.

    PubMed

    Mato, Inés; Huidobro, José F; Simal-Lozano, Jesús; Sancho, M Teresa

    2006-03-01

    A rapid capillary zone electrophoresis (CZE) method with direct ultraviolet (UV) detection has been set up and developed to determine the most important nonaromatic organic acids in honey with a really simple treatment of the sample. The determination of oxalic, formic, malic, succinic, pyruvic, acetic, lactic, citric, and gluconic acids has been carried out in 4 min. The electrolyte composition was phosphate as the carrier buffer (7.5 mM NaH(2)PO(4) and 2.5 mM Na(2)HPO(4)), 2.5 mM tetradecyltrimethylammonium hydroxide (TTAOH) as electroosmotic flow modifier, and 0.24 mM CaCl(2) as selectivity modifier, with the pH adjusted at 6.40 constant value. The running voltage was -25 kV at a thermostated temperature of 25 degrees C. The injections were performed in hydrodynamic mode (30 s), and the detection mode was UV direct at 185 nm. Validation parameters of the method as detection and quantification limits, linearity, precision (repeatability and reproducibility), and recovery were also studied. The advantages related to the technique such as simplicity, short analysis times, and low consumption of chemicals as well as the good validation parameters obtained for this method permit it to be considered as adequate for routine analysis in honey.

  8. [Compositions of organic acids in PM10 emission sources in Xiamen urban atmosphere].

    PubMed

    Yang, Bing-Yu; Huang, Xing-Xing; Zheng, An; Liu, Bi-Lian; Wu, Shui-Ping

    2013-01-01

    The possible organic acid emission sources in PM10 in Xiamen urban atmosphere such as cooking, biomass burning, vehicle exhaust and soil/dust were obtained using a re-suspension test chamber. A total of 15 organic acids including dicarboxylic acids, fatty acids and aromatic acids were determined using GC/MS after derivatization with BF3/n-butanol. The results showed that the highest total concentration of 15 organic acids (53%) was found in cooking emission and the average concentration of the sum of linoleic acid and oleic acid was 24% +/- 14%. However, oxalic acid was the most abundant species followed by phthalic acid in gasoline vehicle exhaust. The ratios of adipic to azelaic acid in gasoline combustion emissions were significantly higher than those in other emission sources, which can be used to qualitatively differentiate anthropogenic and biological source of dicarboxylic acids in atmospheric samples. The ratios of malonic to succinic acid in source emissions (except gasoline generator emissions) were lower (0.07-0.44) than ambient PM10 samples (0.61-3.93), which can be used to qualitatively differentiate the primary source and the secondary source of dicarboxylic acids in urban PM10.

  9. Enzymatically cross-linked alginic-hyaluronic acid composite hydrogels as cell delivery vehicles.

    PubMed

    Ganesh, Nitya; Hanna, Craig; Nair, Shantikumar V; Nair, Lakshmi S

    2013-04-01

    An injectable composite gel was developed from alginic and hyaluronic acid. The enzymatically cross-linked injectable gels were prepared via the oxidative coupling of tyramine modified sodium algiante and sodium hyaluronate in the presence of horse radish peroxidase (HRP) and hydrogen peroxide (H2O2). The composite gels were prepared by mixing equal parts of the two tyraminated polymer solutions in 10U HRP and treating with 1.0% H2O2. The properties of the alginate gels were significantly affected by the addition of hyaluronic acid. The percentage water absorption and storage modulus of the composite gels were found to be lower than the alginate gels. The alginate and composite gels showed lower protein release compared to hyaluronate gels in the absence of hyaluronidase. Even hyaluronate gels showed only approximately 10% protein release after 14 days incubation in phosphate buffer solution. ATDC-5 cells encapsulated in the injectable gels showed high cell viability. The composite gels showed the presence of enlarged spherical cells with significantly higher metabolic activity compared to cells in hyaluronic and alginic acid gels. The results suggest the potential of the composite approach to develop covalently cross-linked hydrogels with tuneable physical, mechanical, and biological properties. PMID:23357799

  10. Enzymatically Cross-linked Alginic-Hyaluronic acid Composite Hydrogels As Cell Delivery Vehicles

    PubMed Central

    Ganesh, Nitya; Hanna, Craig; Nair, Shantikumar V.; Nair, Lakshmi S.

    2013-01-01

    An injectable composite gel was developed from alginic and hyaluronic acid. The ezymatically cross-linked injectable gels were prepared via the oxidative coupling of tyramine modified sodium algiante and sodium hyaluronate in the presence of horse radish peroxidase (HRP) and hydrogen peroxide (H2O2). The composite gels were prepared by mixing equal parts of the two tryaminated polymer solutions in 10U HRP and treating with 1.0% H2O2. The properties of the alginate gels were significanly affected by the addition of hyaluronic acid. The percentage water absorption and storage modulus of the composite gels were found to be lower than the alginate gels. The alginate and composite gels showed lower protein release compared to hyaluronate gels in the absence of hyaluronidase. Even hyaluronate gels showed only approximately 10% protein release after 14 days incubation in phosphate buffer solution. ATDC-5 cells encapsulated in the injectable gels showed high cell viability. The composite gels showed the presence of enlarged spherical cells with significantly higher metabolic activity compared to cells in hyaluronic and alginic acid gels. The results suggest the potential of the composite approach to develop covalently cross-linked hydrogels with tuneable physical, mechanical, and biological properties. PMID:23357799

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

    NASA Technical Reports Server (NTRS)

    Laird, M.; Holmquist, R.

    1975-01-01

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

  12. Impact of metabolism and growth phase on the hydrogen isotopic composition of microbial fatty acids

    PubMed Central

    Heinzelmann, Sandra M.; Villanueva, Laura; Sinke-Schoen, Danielle; Sinninghe Damsté, Jaap S.; Schouten, Stefan; van der Meer, Marcel T. J.

    2015-01-01

    Microorganisms are involved in all elemental cycles and therefore it is important to study their metabolism in the natural environment. A recent technique to investigate this is the hydrogen isotopic composition of microbial fatty acids, i.e., heterotrophic microorganisms produce fatty acids enriched in deuterium (D) while photoautotrophic and chemoautotrophic microorganisms produce fatty acids depleted in D compared to the water in the culture medium (growth water). However, the impact of factors other than metabolism have not been investigated. Here, we evaluate the impact of growth phase compared to metabolism on the hydrogen isotopic composition of fatty acids of different environmentally relevant microorganisms with heterotrophic, photoautotrophic and chemoautotrophic metabolisms. Fatty acids produced by heterotrophs are enriched in D compared to growth water with εlipid/water between 82 and 359‰ when grown on glucose or acetate, respectively. Photoautotrophs (εlipid/water between −149 and −264‰) and chemoautotrophs (εlipid/water between −217 and −275‰) produce fatty acids depleted in D. Fatty acids become, in general, enriched by between 4 and 46‰ with growth phase which is minor compared to the influence of metabolisms. Therefore, the D/H ratio of fatty acids is a promising tool to investigate community metabolisms in nature. PMID:26005437

  13. Impact of metabolism and growth phase on the hydrogen isotopic composition of microbial fatty acids.

    PubMed

    Heinzelmann, Sandra M; Villanueva, Laura; Sinke-Schoen, Danielle; Sinninghe Damsté, Jaap S; Schouten, Stefan; van der Meer, Marcel T J

    2015-01-01

    Microorganisms are involved in all elemental cycles and therefore it is important to study their metabolism in the natural environment. A recent technique to investigate this is the hydrogen isotopic composition of microbial fatty acids, i.e., heterotrophic microorganisms produce fatty acids enriched in deuterium (D) while photoautotrophic and chemoautotrophic microorganisms produce fatty acids depleted in D compared to the water in the culture medium (growth water). However, the impact of factors other than metabolism have not been investigated. Here, we evaluate the impact of growth phase compared to metabolism on the hydrogen isotopic composition of fatty acids of different environmentally relevant microorganisms with heterotrophic, photoautotrophic and chemoautotrophic metabolisms. Fatty acids produced by heterotrophs are enriched in D compared to growth water with εlipid/water between 82 and 359‰ when grown on glucose or acetate, respectively. Photoautotrophs (εlipid/water between -149 and -264‰) and chemoautotrophs (εlipid/water between -217 and -275‰) produce fatty acids depleted in D. Fatty acids become, in general, enriched by between 4 and 46‰ with growth phase which is minor compared to the influence of metabolisms. Therefore, the D/H ratio of fatty acids is a promising tool to investigate community metabolisms in nature. PMID:26005437

  14. Polymorphism of SREBP1 is associated with beef fatty acid composition in Simmental bulls.

    PubMed

    Xu, L; Zhang, L P; Yuan, Z R; Guo, L P; Zhu, M; Gao, X; Gao, H J; Li, J Y; Xu, S Z

    2013-01-01

    The sterol regulatory element binding factor 1 gene (SREBP1) plays an important role in the biosynthesis of fatty acids and cholesterol, and in lipid metabolism. The objective of this study was to investigate the effect of genetic polymorphisms of SREBP1 on the fatty acid composition of muscle and carcass traits in Simmental bulls and Snow Dragon black cattle. The 84-bp insertion/deletion (indel) in intron 5 of the bovine SREBP1 gene was genotyped by polymerase chain reaction to investigate its associations with traits. The results showed that the 84-bp indel in intron 5 was significantly associated with palmitoleic acid (C16:1), stearic acid (C18:0), saturated fatty acids (SFA), triglycerides (TAG), and the C16 index in Simmental bulls (P < 0.05). Cattle with the LL genotype had higher palmitic acid (C16:1), triglycerides, and C16 index but lower stearic acid (C18:0) and SFA compared to those with the LS genotype (P < 0.05). In conclusion, the 84-bp indel of SREBP1 could be used as a genetic marker for selecting Simmental breeding stock for healthier fatty acid composition. PMID:24301949

  15. Isolation of Arabidopsis mutants with altered seed fatty acid composition

    SciTech Connect

    Lemieux, B.; Browse, J.; Somerville, C. Washington State Univ., Pullman )

    1989-04-01

    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.

  16. Soil biodiversity and soil community composition determine ecosystem multifunctionality.

    PubMed

    Wagg, Cameron; Bender, S Franz; Widmer, Franco; van der Heijden, Marcel G A

    2014-04-01

    Biodiversity loss has become a global concern as evidence accumulates that it will negatively affect ecosystem services on which society depends. So far, most studies have focused on the ecological consequences of above-ground biodiversity loss; yet a large part of Earth's biodiversity is literally hidden below ground. Whether reductions of biodiversity in soil communities below ground have consequences for the overall performance of an ecosystem remains unresolved. It is important to investigate this in view of recent observations that soil biodiversity is declining and that soil communities are changing upon land use intensification. We established soil communities differing in composition and diversity and tested their impact on eight ecosystem functions in model grassland communities. We show that soil biodiversity loss and simplification of soil community composition impair multiple ecosystem functions, including plant diversity, decomposition, nutrient retention, and nutrient cycling. The average response of all measured ecosystem functions (ecosystem multifunctionality) exhibited a strong positive linear relationship to indicators of soil biodiversity, suggesting that soil community composition is a key factor in regulating ecosystem functioning. Our results indicate that changes in soil communities and the loss of soil biodiversity threaten ecosystem multifunctionality and sustainability.

  17. Inhibitive detection of benzoic acid using a novel phenols biosensor based on polyaniline-polyacrylonitrile composite matrix.

    PubMed

    Shan, Dan; Shi, Qiaofang; Zhu, Daobin; Xue, Huaiguo

    2007-07-31

    A novel sensitive and stable phenols amperometric biosensor, based on polyaniline-polyacrylonitrile composite matrix, was applied for determination of benzoic acid. The electrochemical biosensor functioning was based on the inhibition effect of benzoic acid on the biocatalytic activity of the polyphenol oxidase (PPO) to its substrate (catechol) in 0.1M phosphate buffer solution (pH 6.5). A potential value of -50 mV versus SCE, and a constant catechol concentration of 20 microM were selective to carry out the amperometric inhibition measurement. The kinetic parameters Michaelis-Menten constant (K(M)(app)) and maximum current (I(max)) in the absence and in the presence of benzoic acid were also evaluated and the possible inhibition mechanism was deduced. The inhibiting action of benzoic acid on the polyphenol oxidase electrode was reversible and of the typical competitive type, with an apparent inhibition constant of 38 microM. This proposed biosensor detected levels of benzoic acid as low as 2x10(-7)M in solution. In addition, the effects of temperature, pH value of solution on the inhibition and the interferences were investigated and discussed herein. Inhibition studies revealed that the proposed electrochemical biosensor was applicable for monitoring benzoic acid in real sample such as milk, yoghurt, sprite and cola. PMID:19071830

  18. A comparative analysis of fatty acid composition and fucoxanthin content in six Phaeodactylum tricornutum strains from diff erent origins

    NASA Astrophysics Data System (ADS)

    Wu, Hualian; Li, Tao; Wang, Guanghua; Dai, Shikun; He, Hui; Xiang, Wenzhou

    2016-03-01

    Phaeodactylum tricornutum is a potential livestock for the combined production of eicosapentaenoic acid (EPA) and fucoxanthin. In this study, six marine diatom strains identified as P. tricornutum were cultured and their total lipid, fatty acid composition and major photosynthetic pigments determined. It was found that the cell dry weight concentration and mean growth rate ranged between 0.24-0.36 g/L and 0.31-0.33/d, respectively. Among the strains, SCSIO771 presented the highest total lipid content, followed by SCSIO828, and the prominent fatty acids in all strains were C16:0, C16:1, C18:1, and C20:5 (EPA). Polyunsaturated fatty acids, including C16:2, C18:2, and EPA, comprised a significant proportion of the total fatty acids. EPA was markedly high in all strains, with the highest in SCSIO828 at 25.65% of total fatty acids. Fucoxanthin was the most abundant pigment in all strains, with the highest in SCSIO828 as well, at 5.50 mg/g. The collective results suggested that strain SCSIO828 could be considered a good candidate for the concurrent production of EPA and fucoxanthin.

  19. Amino acid determination in some edible Mexican insects.

    PubMed

    Ladrón de Guevara, O; Padilla, P; García, L; Pino, J M; Ramos-Elorduy, J

    1995-06-01

    The amino acid contents of edible insects from different provinces of Mexico and reference proteins were analysed by reversed-phase high-performance liquid chromatography and ion exchange chromatography. The insect amino acid contents were higher than the adult requirements indicated by the WHO/FAO pattern.

  20. Identification of QTL with effects on fatty acid composition of meat in a Charolais x Holstein cross population.

    PubMed

    Gutiérrez-Gil, B; Wiener, P; Richardson, R I; Wood, J D; Williams, J L

    2010-08-01

    A whole-genome scan was carried out to detect quantitative trait loci (QTL) influencing beef fatty acid composition using a CharolaisxHolstein population established using a balanced F2 and Backcross breeding design. The phenotypes considered in this study included a total of 24 fatty acid related traits determined in loin muscle samples of the 235 second-generation cross-bred bull calves of the herd. The QTL regression analysis performed, based on 165 microsatellite markers distributed across the 29 bovine autosomes, identified 34 QTL with F-ratios exceeding the 5% chromosome-wide significance threshold. Three of these QTL, one located on chromosome 1 (for the content on linoleic acid, C18:2n-6) and two on chromosome 10 (for the content of gamma-linoleic DPA-docosapentaenoic and DPA-docosapentaenoic, C20:3n-6 and C22:5n-3), also exceeded the 5% genome-wide significance level. A follow-up analysis correcting for intramuscular fat content showed that some of the QTL detected initially (e.g. those localised on chromosome 22) were influenced by fat deposition differences between the founder breeds. The coincident location of some of the linkage associations identified and QTL previously reported for beef fatty acid composition and other meat quality traits, in the same or other cattle populations, provides supporting evidence for the results reported here. PMID:20416790

  1. Effects of calcium soaps of rapeseed fatty acids and protected methionine on milk yield and composition in dairy cows.

    PubMed

    Kowalski, Z M; Pisulewski, P M; Spanghero, M

    1999-11-01

    The objective of this study was to determine the effects of supplementing the diets of dairy cows with Ca soaps of rapeseed fatty acids (CSRFA) and rumen-protected (RP) methionine on their milk yield and composition, including milk protein fractions and fatty acids. Twelve Polish Red Lowland cows were used in a complete balanced two period changeover experiment. The four treatment diets were a control consisting of a total mixed ration of grass silage and concentrates, and the total mixed ration supplemented with RP methionine, CSRFA or RP methionine plus CSRFA. Dry matter intake was not affected by diet. Milk yield increased when cows were given the diet with CSRFA, but supplementation of diets with RP methionine did not affect milk yield. Milk protein content, but not milk protein yield, decreased when CSRFA was given. The addition of RP methionine to the control diet and the CSRFA diet produced similar increases in the milk protein content. Supplementation of the diet with CSRFA significantly changed the milk fatty acid profile: the proportions of 10:0, 12:0, 14:0, 15:0 and 16:0 in milk fat decreased, but those of 18:0 and cis-18:1 increased. We conclude that CSRFA can be used in practical dairy diets to increase milk yield and manipulate its fatty acid composition.

  2. Identification of QTL with effects on fatty acid composition of meat in a Charolais x Holstein cross population.

    PubMed

    Gutiérrez-Gil, B; Wiener, P; Richardson, R I; Wood, J D; Williams, J L

    2010-08-01

    A whole-genome scan was carried out to detect quantitative trait loci (QTL) influencing beef fatty acid composition using a CharolaisxHolstein population established using a balanced F2 and Backcross breeding design. The phenotypes considered in this study included a total of 24 fatty acid related traits determined in loin muscle samples of the 235 second-generation cross-bred bull calves of the herd. The QTL regression analysis performed, based on 165 microsatellite markers distributed across the 29 bovine autosomes, identified 34 QTL with F-ratios exceeding the 5% chromosome-wide significance threshold. Three of these QTL, one located on chromosome 1 (for the content on linoleic acid, C18:2n-6) and two on chromosome 10 (for the content of gamma-linoleic DPA-docosapentaenoic and DPA-docosapentaenoic, C20:3n-6 and C22:5n-3), also exceeded the 5% genome-wide significance level. A follow-up analysis correcting for intramuscular fat content showed that some of the QTL detected initially (e.g. those localised on chromosome 22) were influenced by fat deposition differences between the founder breeds. The coincident location of some of the linkage associations identified and QTL previously reported for beef fatty acid composition and other meat quality traits, in the same or other cattle populations, provides supporting evidence for the results reported here.

  3. Life-history evolution at the molecular level: adaptive amino acid composition of avian vitellogenins

    PubMed Central

    Hughes, Austin L.

    2015-01-01

    Avian genomes typically encode three distinct vitellogenin (VTG) egg yolk proteins (VTG1, VTG2 and VTG3), which arose by gene duplication prior to the most recent common ancestor of birds. Analysis of VTG sequences from 34 avian species in a phylogenetic framework supported the hypothesis that VTG amino acid composition has co-evolved with embryo incubation time. Embryo incubation time was positively correlated with the proportions of dietary essential amino acids (EAAs) in VTG1 and VTG2, and with the proportion of sulfur-containing amino acids in VTG3. These patterns were seen even when only semi-altricial and/or altricial species were considered, suggesting that the duration of embryo incubation is a major selective factor on the amino acid composition of VTGs, rather than developmental mode alone. The results are consistent with the hypothesis that the level of EAAs provided to the egg represents an adaptation to the loss of amino acids through breakdown over the course of incubation and imply that life-history phenotypes and VTG amino acid composition have co-evolved throughout the evolutionary history of birds. PMID:26224713

  4. Spectrophotometric determination of norepinephrine with sodium iodate and determination of its acidity constants

    NASA Astrophysics Data System (ADS)

    Hashem, E. Y.; Youssef, A. K.

    2013-05-01

    A spectrophotometric method is proposed for the determination of norepinephrine (NE) and its bitartrate salts. The method was based on the development of a red color (λmax = 495 nm) with sodium iodate in aqueous alcoholic medium at pH 5. The color was stable for at least 4 hrs. The molar reacting ratio of NE to sodium iodate was 1:4. A linear relationship was obtained between the absorption intensity and NE concentration in the range of 3.384-37.224 μg/ml with detection limit of 0.067 μg/ml and correlation coefficient of 0.9972. The present work facilitated the determination of the three acidity constants, 7.564 ± 0.02, 9.036 ± 0.034, and 10.761 ± 0.023. The reaction mechanism was also described. The proposed method was successfully applied for the determination of NE in pharmaceutical formulations. Results for analysis of bulk drugs and injections agree with those of official methods.

  5. Determination of Acid Dissociation Constant of Pravastatin under Degraded Conditions by Capillary Zone Electrophoresis.

    PubMed

    Takayanagi, Toshio; Amiya, Mika; Shimakami, Natsumi; Yabutani, Tomoki

    2015-01-01

    The acid dissociation constant of pravastatin was determined under degraded conditions. Pravastatin was degraded in an acidic solution (pH = 2.0) for 5 h, and the degradation solution was subjected to the measurement of the effective electrophoretic mobility by capillary zone electrophoresis. Although the amount of pravastatin decreased by the acid degradation, its acid dissociation constant was successfully determined with the residual pravastatin through its effective electrophoretic mobility. The determined acid dissociation constant value agreed well with the one obtained with freshly prepared solution and with some reported values.

  6. Bacterial adherence to titanium, poly-L-lactic acid, and composite hydroxyapatite and poly-L-lactic acid interference screws.

    PubMed

    Masini, Brendan D; Stinner, Daniel J; Waterman, Scott M; Wenke, Joseph C; Gerlinger, Tad L

    2012-01-01

    This study investigates a potential site of bacterial adherence, the implant surface, comparing titanium, poly-L-lactic acid (PLLA), and composite hydroxyapatite and poly-L-lactic acid (PLLA-HA) interference screws using a bioluminescent in vitro model. Interference screws of three materials, titanium (Arthrex, Naples, FL), bioabsorbable poly-L-lactic acid (BIORCI, Smith & Nephew, Andover, MA), and bioabsorbable composite hydroxyapatite and poly-L-lactic acid (BIORCI-HA, Smith & Nephew, Andover, MA) were immersed in a broth of bioluminescent Staphylococcus aureus. The screws were irrigated and then imaged with a photon-capturing camera system yielding a total photon count correlating with residual adherent bacteria. The titanium screws had the lowest mean total bacterial counts followed by the PLLA-HA screws and with the PLLA screws having the highest mean total counts. The difference in means between the titanium group and the PLLA group was statistically significant (p < .001). Titanium interference screws have less bacterial adherence than comparable bioabsorbable PLLA screws.

  7. Beta-galactosidase and selective neutrality. [amino acid composition of proteins

    NASA Technical Reports Server (NTRS)

    Holmquist, R.

    1979-01-01

    Three hypotheses to explain the amino acid composition of proteins are inconsistent (about 10 to the minus 9th) with the experimental data for beta-galactosidase from Escherichia coli. The exceptional length of this protein, 1021 residues, permits rigorous tests of these hypotheses without complication from statistical artifacts. Either this protein is not at compositional equilibrium, which is unlikely from knowledge about other proteins, or the evolution of this protein and its coding gene have not been selectively neutral. However, the composition of approximately 60% of the molecule is consistent with either a selectively neutral or nonneutral evolutionary process.

  8. The influence of different combinations of gamma-linolenic, stearidonic and eicosapentaenoic acids on the fatty acid composition of blood lipids and mononuclear cells in human volunteers.

    PubMed

    Miles, Elizabeth A; Banerjee, Tapati; Calder, Philip C

    2004-06-01

    This study set out to identify whether stearidonic acid (18:4n-3; STA) can be used to increase the eicosapentaenoic acid (20:5n-3; EPA) content of plasma lipids and cells in humans and to understand more about the effects of increased consumption of gamma-linolenic acid (18:3n-3; GLA), STA and EPA in humans. Healthy young males were randomised to consume one of seven oil blends for a period of 12 weeks (9g oil/day) (n = 8-12 subjects/group). Palm oil, sunflower oil, an EPA-rich oil, borage oil (rich in GLA), and Echium oil (rich in STA) were blended in various combinations to generate a placebo oil and oils providing approximately 2g GLA + STA + EPA per day, but in different combinations. Blood was collected at 0, 4, 8 and 12 weeks and the fatty acid compositions of plasma triacylglycerols, cholesteryl esters and phospholipids and of peripheral blood mononuclear cells (PBMCs) determined. Significant effects were observed with each lipid fraction. Neither STA nor its derivative 20:4n-3 appeared in any of the lipid fractions studied when STA (up to 1g/day) was consumed. However, STA (1g/day), in combination with GLA (0.9 g/day), increased the proportion of EPA in some lipid fractions, suggesting that STA-rich plant oils may offer a novel means of increasing EPA status. Furthermore, this combination tended to increase the dihomo-gamma-linolenic acid (20:3n-6; DGLA) content of PBMCs, without an increase in arachidonic acid (AA) (20:4n-6) content. EPA consumption increased the EPA content of all lipid fractions studied. Consumption of GLA (2g/day), in the absence of STA or EPA, increased DGLA content with a tendency to increase AA content in some fractions. This effect was prevented by inclusion of EPA in combination with GLA. Thus, this study indicates that STA may be used as a precursor to increase the EPA content of human lipids and that combinations of GLA, STA and EPA can be used to manipulate the fatty acid compositions of lipid pools in subtle ways. Such effects

  9. The influence of different combinations of gamma-linolenic, stearidonic and eicosapentaenoic acids on the fatty acid composition of blood lipids and mononuclear cells in human volunteers.

    PubMed

    Miles, Elizabeth A; Banerjee, Tapati; Calder, Philip C

    2004-06-01

    This study set out to identify whether stearidonic acid (18:4n-3; STA) can be used to increase the eicosapentaenoic acid (20:5n-3; EPA) content of plasma lipids and cells in humans and to understand more about the effects of increased consumption of gamma-linolenic acid (18:3n-3; GLA), STA and EPA in humans. Healthy young males were randomised to consume one of seven oil blends for a period of 12 weeks (9g oil/day) (n = 8-12 subjects/group). Palm oil, sunflower oil, an EPA-rich oil, borage oil (rich in GLA), and Echium oil (rich in STA) were blended in various combinations to generate a placebo oil and oils providing approximately 2g GLA + STA + EPA per day, but in different combinations. Blood was collected at 0, 4, 8 and 12 weeks and the fatty acid compositions of plasma triacylglycerols, cholesteryl esters and phospholipids and of peripheral blood mononuclear cells (PBMCs) determined. Significant effects were observed with each lipid fraction. Neither STA nor its derivative 20:4n-3 appeared in any of the lipid fractions studied when STA (up to 1g/day) was consumed. However, STA (1g/day), in combination with GLA (0.9 g/day), increased the proportion of EPA in some lipid fractions, suggesting that STA-rich plant oils may offer a novel means of increasing EPA status. Furthermore, this combination tended to increase the dihomo-gamma-linolenic acid (20:3n-6; DGLA) content of PBMCs, without an increase in arachidonic acid (AA) (20:4n-6) content. EPA consumption increased the EPA content of all lipid fractions studied. Consumption of GLA (2g/day), in the absence of STA or EPA, increased DGLA content with a tendency to increase AA content in some fractions. This effect was prevented by inclusion of EPA in combination with GLA. Thus, this study indicates that STA may be used as a precursor to increase the EPA content of human lipids and that combinations of GLA, STA and EPA can be used to manipulate the fatty acid compositions of lipid pools in subtle ways. Such effects

  10. Fatty acid composition of habitual omnivore and vegetarian diets.

    PubMed

    Mann, Neil; Pirotta, Yvonne; O'Connell, Stella; Li, Duo; Kelly, Fiona; Sinclair, Andy

    2006-07-01

    High-fat diets are implicated in the onset of cardiovascular disease (CVD), cancer, and obesity. Large intakes of saturated and trans FA, together with low levels of PUFA, particularly long-chain (LC) omega-3 (n-3) PUFA, appear to have the greatest impact on the development of CVD. A high n-6:n-3 PUFA ratio is also considered a marker of elevated risk of CVD, though little accurate data on dietary intake is available. A new Australian food composition database that reports FA in foods to two decimal places was used to assess intakes of FA in four habitual dietary groups. Analysis using the database found correlations between the dietary intakes of LC n-3 PUFA and the plasma phospholipid LC n-3 PUFA concentrations of omnivore and vegetarian subjects. High meat-eaters (HME), who consumed large amounts of food generally, had significantly higher LC n-3 PUFA intakes (0.29 g/d) than moderate meat-eaters (MME) (0.14 g/d), whose intakes in turn were significantly higher than those of ovolacto-vegetarians or vegans (both 0.01 g/d). The saturated FA intake of MME subjects (typical of adult male Australians) was not different from ovolacto-vegetarian intakes, whereas n-6:n-3 intake ratios in vegetarians were significantly higher than in omnivores. Thus, accurate dietary and plasma FA analyses suggest that regular moderate consumption of meat and fish maintains a plasma FA profile possibly more conducive to good health.

  11. Amino acid composition of lactating mothers' milk and confinement diet in rural North China.

    PubMed

    Ding, Ming; Li, Wei; Zhang, Yumei; Wang, Xiaoli; Zhao, Ai; Zhao, Xiaohui; Wang, Peiyu; Sheng, Qing Hai

    2010-01-01

    This study was designed to investigate the amino acids composition of lactating mothers' milk and their confinement diet in a town in Northern China, as well as to assess the relation of amino acids content in human milk and diet. Forty lactating mothers age 19 to 35 years participated in the study. They were 4 to 180 days postpartum. A 24-hour dietary recall was done and amino acids content of maternal milk was analyzed. The main findings are as follows: (1) The protein content of human milk is 1.58 g/dL and the ratio of EAA to NEAA is about 1:2. The most abundant amino acids in human milk are GLU (16.0%), PRO (10.2%), LEU (8.67%) and the lowest two are MET (1.76%) and TRP (0.91%). (2)The diet contains enough energy and protein, but lacks vitamins A, B and C, indicating that it is a characteristic confinement diet. Grain and eggs are the main source of protein, and soy and fish were consumed less frequently. (3) Amino acids composition in diet and milk are similar; and the correlation of the amino acids patterns between diet and milk is 0.989, demonstrating that the amino acid composition of diet is the foundation of that in human milk. However, almost no relation is found between the amino acids concentration in maternal diet and milk, suggesting that the amino acids content of the diet does not have a direct relation with that of human milk.

  12. [Fatty acids composition of the marine snails Phyllonotus pomum and Chicoreus brevifrons (Muricidae)].

    PubMed

    D'Armas, Haydelba; Yáñez, Dayanis; Reyes, Dilia; Salazar, Gabriel

    2010-06-01

    Muricid species of P. pomum and C. brevifrons are of economic importance in the Caribbean. This study includes a comparative evaluation of fatty acid content in the total lipid composition of Phyllonotus pomum and Chicoreus brevifrons. Snail samples were collected during the rainy, dry and transition seasons, in Punta Arena, Sucre (Venezuela). Total lipids were extracted and the specific fatty acid contents were analyzed by gas chromatography. Lipid concentrations varied between 0.87 and 1.85%, with minimum and maximum values corresponding to C. brevifrons collected during rainy and dry seasons, respectively. In the case of total lipids, a high concentration of unsaturated fatty acids (57.21-70.05%) was observed followed by saturated fatty acids (20.33-31.94%), during all seasons. The polyunsaturated occurred i