A genome-wide association study for the fatty acid composition of breast meat in an F2 crossbred chicken population

The composition of fatty acids determines the flavor and quality of meat. Flavor compounds are generated during the cooking process by the decomposition of volatile fatty acids via lipid oxidation. A number of research on candidate genes related to fatty acid content in livestock species have been published. The majority of these studies focused on pigs and cattle; the association between fatty acid composition and meat quality in chickens has rarely been reported. Therefore, this study investigated candidate genes associated with fatty acid composition in chickens. A genome-wide association study (GWAS) was performed on 767 individuals from an F2 crossbred population of Yeonsan Ogye and White Leghorn chickens. The Illumina chicken 60K significant single-nucleotide polymorphism (SNP) genotype data and 30 fatty acids (%) in the breast meat of animals slaughtered at 10 weeks of age were analyzed. SNPs were shown to be significant in 15 traits: C10:0, C14:0, C18:0, C18:1n-7, C18:1n-9, C18:2n-6, C20:0, C20:2, C20:3n-6, C20:4n-6, C20:5n-3, C24:0, C24:1n-9, monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA). These SNPs were mostly located on chromosome 10 and around the following genes: ACSS3, BTG1, MCEE, PPARGC1A, ACSL4, ELOVL4, CYB5R4, ME1, and TRPM1. Both oleic acid and arachidonic acid contained the candidate genes: MCEE and TRPM1. These two fatty acids are antagonistic to each other and have been identified as traits that contribute to the production of volatile fatty acids. The results of this study improve our understanding of the genetic mechanisms through which fatty acids in chicken affect the meat flavor

THERMODYNAMIC AND SPECTROSCOPIC ANALYSIS OF TERTBUTYL ALCOHOL HYDRATE: APPLICATION FOR THE METHANE GAS STORAGE AND TRANSPORTATION

Recently, clathrate hydrate has attracted much attention because of its energy gas enclathration phenomenon. Since energy gas such as methane, ethane, and hydrogen could be stored in solid hydrate form, clathrate hydrate research has been considerably focused on energy gas storage and transportation medium. Especially, methane hydrate, which is crystalline compound that are formed by physical interaction between water and relatively small sized guest molecules, can contain about as much as 180 volumes of gas at standard pressure and temperature condition. To utilize gas hydrate as energy storage and transportation medium, two important key features: storage capacity and storage condition must be considered. Herein, we report the inclusion phenomena of methane occurred on tert-butyl alcohol hydrate through thermodynamic measurement and spectroscopic analysis by using powder X-ray diffractometer, and 13C solidstate NMR. From spectroscopic analysis, we found the formation of sII type (cubic, Fd3m) clathrate hydrate by introducing methane gas into tert-butyl alcohol hydrate whereas tert-butyl alcohol hydrate alone does not form clathrate hydrate structure. Under equilibrium condition, pressure-lowering effect of methane + tert-butyl alcohol double hydrate was also observed. The present results give us several key features for better understanding of inclusion phenomena occurring in the complex hydrate systems and further developing methane or other gas storage and transportation technique.Non UBCUnreviewe

Phase Equilibria and Spectroscopic Identification of (2-Methylpropane-2-peroxol + Gaseous Guests) Hydrates

In this study, we introduce a new structure-II hydrate former, 2-methylpropane-2-peroxol (tert-butyl hydroperoxide, TBHP), and identify the structure and guest distributions through spectroscopic tools including high-resolution powder diffraction (HRPD), \ub9\ub3C solid-state NMR, and Raman spectroscopy. Here, the (H + L + V) phase equilibrium data of (TBHP + X) hydrates (X = CH4, N2, and O2) were measured at (3.3 to 7.56) MPa and (282.2 to 288.5) K for CH4, (4.0 to 8.5) MPa and (271.6 to 277.5) K for N2, and (4.0 to 8.6) MPa and (273.8 to 279.6) K for O2. The (TBHP + X) hydrate phase equilibria showed that the addition of TBHP increased the structural stability with lower hydrate dissociation pressures when compared with those of pure CH4, N2, and O2 hydrates. However, we noticed that the TBHP did not promote hydrate formation conditions as effectively as tetrahydrofuran.Peer reviewed: YesNRC publication: N

Macroscopic Investigation of Water Volume Effects on Interfacial Dynamic Behaviors between Clathrate Hydrate and Water

This study investigated the effects of the water volume on the interfacial dynamics between cyclopentane (CP) hydrate and water droplet in a CP/<i>n</i>-decane oil mixture. The adhesion force between CP hydrate and various water droplets was determined using the <i>z</i>-directional microbalance. Through repetition of precise measurements over several cycles from contact to detachment, we observed abnormal wetting behaviors in the capillary bridge during the retraction process when the water drop volume is larger than 100 μL. With the increase in water droplet volumes, the contact force between CP hydrate and water also increases up to 300 μL. However, there is a dramatic reduction of increasing rate in the contact forces over 300 μL of water droplet. With the addition of the surfactants of sodium dodecyl sulfate (SDS) and dodecyltrimethylammonium bromide (DTAB) to the water droplet, the contact force between CP hydrate and solution droplet exhibits a lower value and a transition volume of the contact force comes with a smaller solution volume of 200 μL. The water volume effects on the liquid wetting of the probe and the size of capillary bridges provide important insight into hydrate growth and aggregation/agglomeration in the presence of free water phase inside gas/oil pipelines

Abnormal thermal expansion of clathrate hydrates induced by asymmetric guest molecules

We investigated for the first time the abnormal thermal expansion induced by an asymmetric guest structure using high-resolution neutron powder diffraction. Three dihydrogen molecules (H2, D2, and HD) were tested to explore the guest dynamics and thermal behavior of hydrogen-doped clathrate hydrates. We confirmed the restricted spatial distribution and doughnut-like motion of the HD guest in the center of anisotropic sII-S (sII-S=small cages of structure II hydrates). However, we failed to observe a mass-dependent relationship when comparing D2 with HD. The use of asymmetric guest molecules can significantly contribute to tuning the cage dimension and thus can improve the stable inclusion of small gaseous molecules in confined cages.Peer reviewed: YesNRC publication: Ye

Experimental Verifications of Abnormal Chlorinity appearing in Natural Deep-Sea Gas Hydrate

The chloride anion is known to be the most abundant salt ion in sea water. At the regions such as ODP Sites 1249 and 1250 the highly enriched chloride concentration is observed in a zone extended from near the sediment surface (~1 mbsf) to depths about 25 mbsf. Here, we designed the in-situ electric circuit system for measuring chloride concentration within reliable accuracy. In the cylindrical cell the 5-10 tubes having holes on the wall and electrodes were equipped around clay mixture. The open holes were made to regulate to a certain degree the interface area between methane gas and clay sample. As may be anticipated, the chloride concentration abnormally increased under fast rate condition for forming methane hydrate, but no noticeable concentration change was detected under relatively low rate. In fact, the present experiment seems to be a lot deficient to investigate the ion diffusion and moreover does not fully reflect the real deep-sea floor condition, but the meaningful results for describing the abnormal salinity enrichment might be drawn. The physical effects of chloride anions on surface morphologies of methane hydrate formed in the sediments were additionally examined with the Field Emission-Scanning Electronic Microscope (FE-SEM).Non UBCUnreviewe

Spectroscopy Identification and Thermodynamic Stability of tert-Butyl Nitrite and Methane Clathrate Hydrate

Structure-H hydrate has been highlighted due to its higher gas storage capacity and favorable thermal stability. Here, we introduce a new structure-H hydrate former, tert-butyl nitrite, and identify it through spectroscopic analysis. The hydrate structure and guest distribution were examined by using powder X-ray diffraction, Raman spectroscopy, and solid-state high-power decoupling 13C NMR spectroscopy. The phase equilibria (Lw + H + Lg + V) of tert-butyl nitrite + CH4 hydrate were measured at pressures from (3 to 4.5) MPa and at temperatures from (277 to 282) K. We also investigated the kinetic behavior of this new high-polarity hydrate former.close0