[Sorption of aminoglycoside antibiotics from unfiltered culture fluid]. / Sorbtsiia antibiotikov-aminoglikozidov iz nefil'trovannoi kul'tural'noi zhidkosti.

Sorption of aminoglycosides such as sisomicin, gentamicin, kanamycin and streptomycin from the non-filtrated fermentation broth by carboxylic cation exchange resins under the static conditions was studied. The optimal conditions for the sorption of the aminoglycosides and their subsequent desorption were determined (the ratio of the volumes of the sorbent and fermentation broth and the time of the sorption and desorption).

[Sorption of aminoglycoside antibiotics by weakly acidic cation exchangers]. / Sorbtsiia antibiotikov aminoglikozidov slabokislotnymi kationitami.

Sorption of aminoglycoside antibiotics close by their chemical structures such as gentamicin, sisomicin and kanamycin by polyacrylic and polymetaacrylic cation exchange resins was studied. The generality of the sorption process (kinetics and statics) on the carboxylic cation exchange resins with participation of the ions of the aminoglycoside antibiotics was shown.

[Equilibrium distribution of weak electrolytes in an organic solvent-water system]. / Ravnovesnoe raspredelenie slabykh élektrolitov v sisteme organicheskii rastvoritel'-voda.

Distribution of cephalotin, 2-tienylacetic acid, phenacetyl-D-(--)-alpha-aminophenylacetic acid, weak acids and D-(--)-alpha-amino-phenylacetic acid methyl ether, a weak base in two-phase systems containing two immiscible liquid phases was studied. The constants of the intraphase and interphase equilibrium necessary for complete quantitative description of the system of electrolyte aqueous solution-organic solvent were determined.

[Physiochemical properties of 7-aminoacetoxycephalosporanic acid]. / Fiziko-khimicheskie svoistva 7-aminoatsetoksitsefalosporanovoi kisloty.

Potentiometric titration of the zwitter-ion of 7-aminoacetoxycephalosporanic acid (7-ACA) was performed and the constants of its ionization were estimated. The minimum solubility of the 7-ACA zwitter-ion (20 degrees C, 0.1 M NaCl) was determined and the solubility curve of 7-ACA at wide pH ranges was calculated. Equilibrium of the cationic, zwitter-ionic and anionic forms of 7-ACA was estimated as dependent on pH.

[E. coli penicillin amidase. Physico-chemical properties of the enzyme covalently bound to the 2-(3'-amino-4'-methoxyphenyl)-sulfonylethyl ester of cellulose]. / Penitsillinamidaza iz E. coli. Nekotorye fiziko-khimicheskie svoistva fermenta, kovalentno sviazannogo s 2-(3'-amino-4'-metoksifenil)-sul'fonilétilovym éfirom tselliulozy.

The effect of the procedure of the enzyme binding with the carrier on the properties of the heterogenous catalyst obtained by covalent binding of penicillinamidase (PA) with cellulose 2-(3'-amino-4'-methoxyphenyl)-sulphonylethyl ether by means of the bifunctional reagent, i.e. glutaric aldehyde was studied. It was shown that the amount of the bound enzyme increased with a rise in the amount of the enzyme taken for the binding, while the binding efficiency characterizing the part of the active enzyme in the total amount of the bound PA decreased practically 2 times. The use of the enzyme preparations with different purify levels for the binding provided differentiation of the effects resulting in the activity loss on immobilization. In other words it provided separate estimation of the inactivation effect of the matrix and the immobilization procedure, as well as the interaction of the enzyme molecules with each other and other protein molecules.