Plant latex peptidases as biocatalysts for the synttheses of amino acyl alkylamides

FAIT, MARÍA ELISA; PADRÓ, JUAN MANUEL; MENDEZ, LETICIA; CLEPÉS, PERE; MORCELLE, SUSANA

Búzios, Brasil

Workshop; VII Workshop on Biocatalysis and Biotransformations. 1° Simposio Latinoamericano de Biocatálisis y Biotransformaciones. Ferrodura Resort, Búzios, Brasil.; 2014

INTRODUCTION Amino acid based surfactants are of great interest in the field of novel surfactants research, mainly because of their environmentally friendly character. The hydrophobic group can be attached to amino acids by their carboxylic moiety leading to different types of surfactants. In this work, we have focused on the syntheses of six amino acid alkylamides using plant latex peptidases adsorbed onto polyamide as biocatalysts1 (araujian from Araujia sericifera, a South American native milkweed, and papain from Carica papaya) using different N-carbobenzoxy-amino acid derivatives (Z-AA) as acyl donors and decyl- and dodecylamine as nucleophiles. For kinetic controlled syntheses, methyl esters of Z-AA were obtained by the thionyl chloride method2. All the reactions were performed in acetonitrile 0.25% H2O (v/v). Thermodynamically and kinetically controlled syntheses were tested3. Enzyme time course reaction was monitored up to 72 h. RESULTS AND DISCUSSION Results indicated that thermodynamic controlled synthesis was successful for the production of the Z-Ala alkylamides. Although relatively good yields were obtained for the synthesis under thermodynamic control of the Gly derivatives the formation of insoluble adducts in the case of the condensation reaction between Z-Gly-OH and Z-Leu-OH with the alkylamines avoided the full reaction, so the kinetic approach was tested. In this case, yields improved remarkably. For papain as biocatalyst, conversions of 99.10.3% in Z-Ala-NHC10 and 83.10.9% in Z-Ala-NHC12 after 72 h reaction. reaching conversions of 92.50.1% and 91.30.4% in Z-Gly-NHC10 and Z-Gly-NHC12, respectively, in 3 h reaction time. For the syntheses of the Z-Leu alkylamides by this approach, yields were 965% and 902% in Z-Leu-NHC10 and Z-Leu-NHC12 respectively after 72 h reaction. When araujiain was tested as biocatalyst, the best yields in Z-Ala-NHC10 and Z-Ala-NHC12 were 65.50.6% and 684% in 24 and 72 h respectively, whereas yields in Z-Gly-NHC10 and Z-Gly-NHC12 were 751% and 7312% respectively (both after 72 h reaction). In the case of the synthesis of Z-Leu-NHC10 and Z-Leu-NHC12, the conversion yields were 22.310.06 (48 h) and 301% (72 h), respectively. CONCLUSION Amino acyl alkylamides with potential tensioactive activity were successfully synthetized using plant cysteine peptidases as biocatalysts. Carboxy moiety derivatization of the acyl donor was necessary for the synthesis of the Gly and Leu amides to avoid adduct formation. In general, araujiain showed lower yields than papain. When kinetic controlled synthesis using araujiain as biocatalist was tested, higher conversions in hydrolysis by products (hydrolysis products) were observed. ACKNOWLEDGEMENTS Finantial support by CONICET (PIP 0150) and Universidad Nacional de La Plata (X-613) is ackowledged. MEF was awarded CONICET scholarship. JMP and LM were awarded CONICET postdoctoral scholarships. SRM belongs to CONICET Researcher Career. REFERENCES 1. Morcelle, S.R.; Liggieri, C.S.; Bruno, M.A.; Priolo, N.; Clapés, P. Screening of plant peptidases for the synthesis of arginine-based surfactants. J. Mol. Catal. B: Enzymatic, 2009,57,177-182. 2. Brenner, M. and Huber, W. Herstellung von α-Aminosäureestern durch Alkoholyse der Methylester. Helvetica Chim. Acta, 1953, 36,1109-1115. 3. Bordusa, F. Proteases in organic synthesis. Chem. Rev. 2002,102,4817-4867.