Browsing by Author "Illanes, Andrés"
Now showing items 1-9 of 9
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Effect of cosolvent and pH on the kinetically controlled synthesis of cephalexin with immobilised penicillin acylase
Aguirre Céspedes, Carolina; Toledo, Mauricio; Medina, Valentina; Illanes, Andrés (2002)The effect of co-solvents was studied on the kinetically controlled synthesis of cephalexin with immobilised penicillin acylase (PA). Yield correlated well with the ratio of initial rates of cephalexin synthesis to acyl ... -
Evaluation of the incidence of diffusional restrictions on the enzymatic reactions of hydrolysis of penicillin G and synthesis of cephalexin
Valencia, Pedro; Wilson, Lorena; Aguirre Céspedes, Carolina; Illanes, Andrés (2010)The impact of mass transfer limitations on penicillin G acylase immobilized in glyoxyl-agarose particles of different sizes and enzyme loads was evaluated for the reactions of hydrolysis of penicillin G and synthesis of ... -
Optimization of cephalexin synthesis with immobilized penicillin acylase in ethylene glycol medium at low temperatures
Illanes, Andrés; Anjarí, Soledad; Altamirano, Claudia; Aguirre Céspedes, Carolina (2004)Organic cosolvents, and among them, polyols, are suitable media to perform the enzymatic synthesis of -lactam antibiotics with immobilized penicillin acylase, because they effectively reduce water activity, depressing ... -
Optimization of Yield in Kinetically Controlled Synthesis of Ampicillin with Immobilized Penicillin Acylase in Organic Media
Illanes, Andrés; Anjarí, Soledad; Arrieta, Rosa; Aguirre Céspedes, Carolina (2002)Immobilized penicillin acylase is a moderately priced versatile enzyme, that is able to catalyze the synthesis of derived penicillins and cephalosporins from the corresponding β-lactam nuclei and proper side-chain precursors. ... -
Partition and substrate concentration effect in the enzymatic synthesis of cephalexin in aqueous two-phase systems
Aguirre Céspedes, Carolina; Concha, Irene; Vergara, Judith; Riveros, Ruby; Illanes, Andrés (2010)The kinetically controlled synthesis of cephalexin in aqueous two-phase systems was studied, using immobilized penicillin acylase, 7-amino 3-desacetoxycephalosporanic acid as nucleophile and phenylglycine methyl ester as ... -
Production of cephalexin in organic medium at high substrate concentrations with CLEA of penicillin acylase and PGA-450
Illanes, Andrés; Wilson, Lorena; Altamirano, Claudia; Cabrera, Z.; Álvarez, L.; Aguirre Céspedes, Carolina (2007)The kinetically controlled synthesis of cephalexin in ethylene glycol was previously optimized at moderate substrate concentrations obtaining yields close to stoichiometric. A study is now presented on the production of ... -
Synthesis of cephalexin in aqueous medium with carrier-bound and carrier-free penicillin acylase biocatalysts
Illanes, Andrés; Wilson, Lorena; Aguirre Céspedes, Carolina (2009)The use of very high substrate concentrations favors the kinetically controlled synthesis of cephalexin with penicillin acylase (PA) not only by Michaelian considerations, but also because water activity is depressed, so ... -
Synthesis of cephalexin in organic medium at high substrate concentrations and low enzyme to substrate ratio
Illanes, Andrés; Altamirano, Claudia; Fuentes, M.; Zamorano, Francisca; Aguirre Céspedes, Carolina (2005)The kinetically controlled synthesis of cephalexin (CEX) in ethylene glycol (EG) was previously optimized at moderate substrate concentrations and high enzyme to substrate ratio, obtaining yields close to stoichiometric. ... -
Synthesis of cephalexin with immobilized penicillin acylase at very high substrate concentrations in fully aqueous medium
Aguirre Céspedes, Carolina; Wilson, Lorena; Corretea, Octavio; Tavernini, Luigini; Illanes, Andrés; Zamorano, Francisca (2007)The presence of organic cosolvents was previously considered necessary to obtain high conversion yields in the synthesis of β-lactam antibiotics with immobilized penicillin acylase, and it is so when working at moderate ...