title: [Immobilization of Citrobacter freundii cells with tyrosine phenol-lyase activity by entrapment in natural gels].
abstract: A comparative study on immobilization of Citrobacter freundii cells by entrapment in carrageenan, agar, agar-agar, and gelatin gels (5, 10, and 15%) was carried out. Gelatin gels were treated with glutaraldehyde to make them more rigid. As a result, the tyrosine phenol-lyase activity of these samples was less than that of free cells (about 40%). The yield of TP-lyase activity was 40--60% when cells were immobilized in 5% and 7% agar and agar-agar gels. The cells entrapped in carrageenan gels, the concentration of which was varied from 2 to 10%, possessed the highest tyrosine phenol-lyase activity (up to 90%). The efficiency of cell entrapment was high for all the carrier and equal to 70--90%. The plastic strength and swelling of the above gels, as well as the phenol adsorption on the carriers and the release of the bacterial cells from them were studied under the conditions of tyrosine phenol-lyase reaction.
mesh_terms: D000327:Adsorption; D002954:Citrobacter / Q000201:enzymology*; D004800:Enzymes, Immobilized / Q000378:metabolism*; D005782:Gels; D007700:Kinetics; D008190:Lyases / Q000378:metabolism*; D008722:Methods; D010636:Phenols / Q000378:metabolism; D014443:Tyrosine / Q000096:biosynthesis; D014447:Tyrosine Phenol-Lyase / Q000378:metabolism*
chemical_list: D004800:Enzymes, Immobilized; D005782:Gels; D010636:Phenols; D014443:Tyrosine; D008190:Lyases; D014447:Tyrosine Phenol-Lyase
vernacular_title: Immobilizatsiia kletok Citrobacter freundii s tiroz-infenol-liaznoĭ aktivnost'iu metodom vkliucheniia v prirodnye geli.