Electronic Journal of Biotechnology ISSN:
0717-3458 |
Vol. 6 No. 1, Issue of April 15, 2003 |
© 2003 by Universidad Católica de Valparaíso
-- Chile |
Received October 29, 2002 / Accepted January 22, 2003 |
Enzymatic
synthesis of short chain citronellyl esters by a new lipase from Rhizopus
sp
Gabriela Alves
Macedo*
Faculdade de Engenharia de Alimentos
Universidade Estadual de Campinas
CP 6121, CEP 13083970, Campinas, SP, Brazil
Tel: 55 19 37882164
Fax : 55 19 32892832
E-mail:
gmacedo@fea.unicamp.br
Maria Mercedez
Soberón Lozano
Instituto
de Bioquímica e Nutrição
Faculdade de Medicina
Universidade de San Marcos
Lima, Peru
Gláucia
Maria Pastore
Faculdade
de Engenharia de Alimentos
Universidade Estadual de Campinas
CP 6121, CEP 13083970, Campinas, SP, Brazil
Tel: 55 19 37883887
Fax: 55 19 37883887
E-mail: glaupast@fea.unicamp.br
*Corresponding
author
Keywords:
esters, flavor, lipases, synthesis.
Short chain
citronellyl esters were synthesized by a new microbial lipase from
Rhizopus sp strain isolated and lipase produced at UNICAMP,
Brazil. Direct esterification and transesterification reactions have
been performed to produce citronellyl acetate and butyrate in a free-solvent
system and with n-hexane in reaction medium. Reaction mixture for
direct esterification and transesterification was carried out at 45ºC
in equimolar concentration of substrates: acid or ester and alcohol.
Only citronellyl butyrate was synthesized by direct esterification
with yields from 95 to 100% after 24 hrs. of reaction time, with or
without n-hexane. Citronellyl acetate was synthesized by transesterification
with ethyl acetate and cytronellol, with yield of 58% after 48 hrs.
and 48% of conversion for reaction butyl acetate and cytronellol.
The results suggest that the size of the aliphatic chain from acyl
donor was importance to conversion rate. Acids with more than two
carbons showed to be better substrate for Rhizopus sp lipase.
Transesterification reaction showed different behaviour, ester substrate
with four carbons was better than six carbon for citronellyl acetate
synthesis.
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