Tag Archives: HPLC

Copurification of chicken liver soluble thiamine monophosphatase and low molecular weight acid phosphatase

I. K. Kolas, A. F. Makarchikov

Grodno State Agrarian University;
Institute of Biochemistry of Biologically Active Compounds, National Academy of Sciences of Belarus;
e-mail: a_makarchikov@yahoo.com

Thiamine monophosphatase (ThMPase) is an enzyme of thiamine metabolism in animals whose molecular nature has still to be elucidated. In this study we have achieved a 714-fold purification of a soluble enzyme possessing ThMPase activity from a chicken liver extract. In addition to ThMPase, acid phosphatase activity was traced during purification. Both activities proved to have coincident elution profiles at all chromatographic steps implying the same enzyme involved. The molecular weight of the enzyme was 18 kDa as estimated by gel filtration. Along with ThMP and p-nitrophenyl phosphate, the purified enzyme was capable of hydrolyzing flavin mononucleotide as well as phosphotyrosine. Subcellular distribution of ThMPase activity was also explored indicating its cytosolic localization. The results of the present work imply the involvement of low molecular weight acid phosphatase in thiamine metabolism in the chicken liver.

Kinetic pattern of folic acid release from polyurethane matrices of varied structures

M. V. Grigorieva

Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv;
e-mail: mayagrigorieva@gmail.com

The development of new bioactive polymeric materials is very topical. The goal of the present work was to use an optimized reversed-phase HPLC method to determine the release of folic acid (FA) from polyurethane carriers of different structures in vitro. Two types of polymeric samples were studied as FA carriers: linear (covalent bonds between FA and the carrier; 13 mass % and 26 mass % FA – samples 1 and 2) and cross-linked (hydrogen bonds between FA and the carrier; 1 mass % FA and 6 mass % FA – samples 3 and 4). The rate and pattern of the FA release was shown to depend on the way of FA immobilization on the polymeric carrier and the polymer structure. The cumulative amount of FA released from the linear samples (1 and 2) into model medium on the 28th day was 1.20 mg/ml and 2.17 mg/ml, respectively. The cumulative amount of FA released from the cross-linked samples (3 and 4) on the 28th day was 0.16 mg/ml and 0.38 mg/ml, respectively.