Inmovilización de lipasa B de Candida Antarctica en plásticos no biodegradables. Aplicación en la esterificación de R/S-ibuprofeno

En este trabajo se presenta la evaluación de plásticos no biodegradables provenientes de residuos sólidos urbanos, como soportes de la lipasa B de Candida antárctica (CALB), y su aplicación en la esterificación de R/S-ibuprofeno con etanol. Se llevó a cabo la adsorción (selectiva y total) de CALB en polietilenftereftalato (PET), polipropileno (PP) y derivados de dichos polímeros

Estudios catalíticos y moleculares de la esterificación de ibuprofeno y ketoprofeno con glicerol

Se investigó la esterificación de ibuprofeno y ketoprofeno racémicos con glicerol catalizada por el biocatalizador comercial Novozym® 435. Las reacciones tipo “batch” se llevaron a cabo a una temperatura de 45°C, usando 2-propanol como solvente. Se estudiaron varias relaciones molares profeno:glicerol

Syntheses of dipeptide alcohols and dipeptide aldehyde precursors catalyzed by plant cysteine peptidases

Two different cysteine peptidases obtained from plant latex (papain from Carica papaya and araujiain from Araujia hortorum) demonstrated to be good catalysts for the condensation of coded and non-coded Cbz-amino acids and amines such as amino alcohols and amino acetals in acetonitrile containing 1% (v/v) water. Both kinetically and thermodynamically controlled syntheses were proved. Thermodynamic approach was selected since the conversions in product found were similar to those obtained by the kinetic approach; furthermore, a minor number of synthetic steps were needed. For the Cbz-amino acids tested, conversions were higher than 80% at 48–72 h of reaction, except for the Phg derivative, which produced conversions of ca. 40 and 20% for papain and araujiain, respectively. Product yields for the scaled up reactions were similar to the conversions obtained in microscale synthesis. The flexibility of both enzymes for the nucleophile allowed the condensation reaction of Cbz-Ala-OH with an amino diacetal derivative. The resulting dipeptide diacetal derivative can be easily tranformed into a dipeptide aldehyde by acid hydrolysis.Centro de Investigación de Proteínas Vegetale

Catalytic and molecular insights of the esterification of ibuprofen and ketoprofen with glycerol

[EN] The esterification of rac-ibuprofen and rac-ketoprofen with glycerol catalyzed with the commercial biocatalyst Novozym® 435 was investigated at 45 °C with various profen: glycerol molar ratios using 2-propanol as co-solvent in a batch type reaction. The conversion of rac-ibuprofen reached 46%, with an enantiomeric excess towards the S-enantiomer of 42%. When 1:4 ibuprofen:glycerol molar ratio was assayed, 75% of the R-ibuprofen reacted with glycerol towards the monoglyceride with 99% selectivity, which is highly relevant in the field of prodrugs synthesis. The conversion of rac-ketoprofen was lower, 17 % vs. 46 % of rac-ibuprofen, and the esterification afforded both the monoglyceride (70%) and diglyceride (30%) regardless of the ketoprofen:glycerol molar ratio. Investigations of the esterification at molecular level through concentration-modulated infrared spectroscopy, static ATR-FTIR and in situ Raman spectroscopy showed the continuous decay of the species belonging to rac-ibuprofen and glycerol providing further evidences of the reaction. Moreover, the interaction of CALB with ibuprofen modifies the contribution of the ordered structures of the lipase, which might be related with the improved catalytic performance in the esterification of that profen.Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) of Argentina (project PIP 11220130100171 CO), Universidad Nacional de La Plata (project 11X-745), ANPCyT (PICT-2018-3762), and CSIC of Spain (project I-COOP+2017, COOPB20336