EFFECTS OF CREATINE AND VITAMIN E ON MUSCLE ENERGETIC METABOLISM, ANTIOXIDANT STABILITY AND MEAT QUALITY OF PIGS

Abstract LAHUČKÝ, R., BUČKO, O., HAŠČÍK, P., LIPTAJ, T.: Eff ects of creatine and vitamin E on muscle energetic metabolism, antioxidant stability and meat quality of pigs. Acta univ. agric. et silvic. Mendel. Brun., 2012, LX, No. 5, pp. 151-160 The eff ects of supplementing the diet of pigs with creatine monohydrate (CMH) and vitamin E on blood plasma creatine concentration, vitamin E level in muscle, muscle energy metabolism, antioxidant capacity and meat (musculus longissimus dorsi) quality of pigs (DNA tested and negative on malignant hyperthermia) were investigated. Two treatments were used: supplementation with CMH alone (2 g.kg −1 of feed, 10 days before slaughter); and supplementation with both vitamin E (500 mg -tocopherol.kg −1 of feed for minimum of 30 days) and CMH (2 g.kg −1 of feed, 10 days before slaughter). Pigs supplemented with CMH alone showed elevated plasma creatine concentration (P ≤ 0.05). Phosphorus nuclear magnetic resonance ( 31 P NMR) measurements on post mortem (15 min.) muscle samples showed the highest phosphocreatine levels and ratio PCr/Pi (P ≤ 0.05) in CMH supplemented pigs alone and in combination with vitamin E. Dietary supplementation with vitamin E signifi cantly (P ≤ 0.05) increased the concentration of -tocopherol in meat. Supplementation with CMH alone or in combination with vitamin E resulted in higher (P = 0.07) a values of loin chops at 5 days of storage. Antioxidative capacity (measured as MDA production a er incubation of longissimus muscle homogenates with Fe 2+ /ascorbate) was substantially improved by vitamin E and somewhat by CMH supplementation. meat quality, pork, creatine monohydrate, vitamin E Previous research has examined the eff ects of supplementing swine fi nishing diets with creatine

van der Waals Interactions in Material Modelling

Van der Waals (vdW) interactions stem from electronic zero-point fluctuations and are often critical for the correct description of structure, stability, and response properties of molecules and materials, including biomolecules, nanomaterials, and material interfaces. Here, we give a conceptual as well as mathematical overview of the current state of modeling vdW interactions,focusing in particular on the consequences of different approximations for practical applications. We present a systematic classification of approximate first-principles models based on the adiabatic-connection fluctuation-dissipation theorem, namely the nonlocal density functionals, interatomic methods, and methods based on the random-phase approximation. The applicability of these methods to different types of materials and material properties is discussed in connection with availability of theoretical and experimental benchmarks. We conclude with a roadmap of the open problems that remain to be solved to construct a universal, efficient, and accurate vdW model for realistic material modeling

Dissociative iodomethane adsorption on Ag-MOR and the formation of AgI clusters: An ab initio molecular dynamics study

International audience1 Radioactive iodine species belong to the most dangerous components of nuclear effluents and waste produced by nuclear facilities and this fact motivates a significant effort in development of technologies for their efficient trapping. In this work we use computer simulations at the periodic DFT level to investigate dissociative adsorption of iodomethane on silver exchanged mordenite, which is among the most effective sorbents of iodine species available as of today. The structure, energetics, and mobility of complexes Ag-(CH 3 I) and Ag-(CH 3 I) 2 formed upon adsorption of iodomethane on Ag + sites are investigated using the ab-initio MD approach. The free-energy profiles for the reaction CH 3 I + Ag-MOR → AgI + CH 3-MOR are determined using the blue moon ensemble technique. The AgI species formed as a product of dissociative adsorption are shown to combine spontaneously into small clusters (AgI) n with the dimensions restricted by the size and geometry of confining void. The structure and energetics of the (AgI) n species are analysed in detail and compared with the available experimental and theoretical data. The internal energy of formation of clusters in mordenite is shown to contribute significantly to the shift of equilibrium from undissociated to dissociated form of adsorbed CH 3 I