Gerardo Zaragoza-Galán

Dr. Gerardo Zaragoza-Galán


Research Focus & Metrics

Academic Career Length

12Years (2015-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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11 April 2018 in BMC Chemistry
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ASAlejandro Sustaita-Rodríguez
Alejandro Sustaita-Rodríguez
VRVíctor Ramos-Sánchez
Víctor Ramos-Sánchez
ACAlejandro Camacho-Davila
Alejandro Camacho-Davila
GZGerardo Zaragoza-Galán
Gerardo Zaragoza-Galán
JEJosé C. Espinoza-Hicks
José C. Espinoza-Hicks
DCDavid Chavez-Flores
David Chavez-Flores
Nowadays the industrial chemistry reactions rely on green technologies. Enzymes as lipases are increasing its use in diverse chemical processes. Epoxidized fatty acid methyl esters obtained from transesterification of vegetable oils have recently found applications as polymer plasticizer, agrochemical, cosmetics, pharmaceuticals and food additives. In this research article, grapeseed, avocado and olive oils naturally containing high percents of mono and poly unsaturations were used as starting materials for the production of unsaturated fatty acid methyl esters. The effect of lauric acid as an active oxygen carrier was studied on epoxidation reactions where unsaturated fatty acid methyl esters were converted to epoxy fatty acid methyl esters using immobilized Candida antarctica Lipase type B as catalyst and hydrogen peroxide as oxygen donor at mild temperature and pressure conditions. After this study it was confirmed by 1H NMR, 13C NMR and GC–MS that the addition of lauric acid to the enzymatic reaction is unnecessary to transform the alkenes in to epoxides. It was found that quantitative conversions were possible in despite of a carboxylic acid absence.

14 May 2015 in Molecules
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GLGabriela López-Frías
Gabriela López-Frías
ACAlejandro Camacho-Davila
Alejandro Camacho-Davila
DCDavid Chavez-Flores
David Chavez-Flores
GZGerardo Zaragoza-Galán
Gerardo Zaragoza-Galán
VRVíctor Ramos-Sánchez
Víctor Ramos-Sánchez
A palladium mediated synthesis of a common synthon for the syntheses of antioxidant analogues of naturally occurring salvianolic acids is presented. The synthetic route may be used to obtain analogues with a balanced lipophilicity/hydrophilicity which may result in potentially interesting LDL antioxidants for the prevention of cardiovascular diseases.

9 September 2015 in BMC Chemistry
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CECarlos A. Enríquez-Núñez
Carlos A. Enríquez-Núñez
ACAlejandro Camacho-Davila
Alejandro Camacho-Davila
VRVíctor Ramos-Sánchez
Víctor Ramos-Sánchez
GZGerardo Zaragoza-Galán
Gerardo Zaragoza-Galán
LBLourdes Ballinas
Lourdes Ballinas
DCDavid Chavez-Flores
David Chavez-Flores
Malathion (R,S)-diethyl-2-[(dimethoxyphosphorothioyl)sulfanyl]butanedioate is a chiral organophosphorus compound used widely as pesticide for suppression of harmful insects such as mosquitoes. It is well known that in biological systems (R)-malathion is the active enantiomer, therefore a sustainable approach could be the use of only the biologically active enantiomer. The resolution of the commercial racemic mixture to obtain the pure active enantiomer combined with a recycling of the undesired enantiomer through a racemization process could be an attractive alternative to reduce the environmental impact of this pesticide. Thus, this work evaluates the use of four commercially available lipases for enantioselective hydrolysis and separation of malathion enantiomers from the commercial racemic mixture. Several lipases were methodologically assessed, considering parameters such as enzyme concentration, temperature and reaction rates. Among them, Candida rugosa lipase exhibited the best performance, in terms of enantioselectivity, E = 185 (selective to the (S)-enantiomer). In this way, the desired unreacted (R)-enantiomer was recovered in a 49.42 % yield with an enantiomeric excess of 87 %. The monohydrolized (S)-enantiomer was recovered and racemized in basic media, followed by esterification to obtain the racemic malathion, which was recycled. In this way, an enantioenriched mixture of (R)-malathion was obtained with a conversion of 65.80 % considering the recycled (S)-enantiomer. This work demonstrated the feasibility of exploiting Candida rugosa lipase to kinetically resolve racemic malathion through an environmentally friendly recycling of the undesired (S)-enantiomer.