A review of mathematical models describing the transport of solutes and single particles in fluid flow

Abstract

The work demonstrates the possibility of using electron impact mass spectrometry (EI) on a MB-80A device ("Hitachi", Japan) with a double electron focusing for analysis of [ 2 H, 13 C]amino acid mixtures of L-phenylalanine producing strain of Brevibacterium methylicum and L-leucine-producing strain of Methylobacillus flagellatum, and [ 2 H, 13 C]amino acids of the total biomass protein isolated while growing the bacterial cells on media containing as a source of stable isotopes [ 2 H]methanol, [ 13 C] methanol and 2 H 2 O. For mass-spectrometric analysis of the level of incorporation of stable isotopes 2 H and 13 C into the molecules of [ 2 H, 13 C]amino acids the multi-componential mixtures of [ 2 H, 13 C]amino acids, derived from cultural media and protein hydrolysates after hydrolysis in 6 M 2 HСl (3 % phenol) and 2 M Ва(OH) 2 were modified into N-benzyloxycarbonyl-derivatives of [ 2 H, 13 C]amino acids as well as into the methyl esters of N-dansyl-derivatives of [ 2 H, 13 C]amino acids, which were separated by the method of reverse phase high performance liquid chromatography (RP HPLC) on a column with octadecylsilane gel Separon SGX C18. The levels of 2 H and 13 С enrichment of secreted amino acids and amino acid residues of protein were found to be varied depending on the metabolic pathways of biosynthesis and concentration of 2 Hand 13 C-labelled substrates in growth media from 20.0 atom. % to L-leucine/isoleucine up to 97.5 atom. % for L-alanine.