resumo
Linoleic acid was converted into hydroperoxides by a Gaeumannomyces graminis tritici lipoxygenase produced recombinantly in Trichoderma reesei. Hydroperoxide production was optimized using a face-centred experimental design in order to study the effects of pH, temperature and time on the conversion of linoleic acid into four regioisomeric hydroperoxyoctadecadienoic acids (HPODE): 13-(Z,E)-, 9-(E,Z)-, 13-(E,E)-, 9-(E,E)-HPODE. Fitting equations described satisfactorily the system behavior and showed that reaction time was the most influencing independent variable. A set of independent variables (pH = 6.7, temperature = 23.9 degrees C and time = 18 h) allowed to obtain high yields of hydroperoxides (88.0%) with a good selectivity for the 13-(Z,E)-HPODE isomer (47.4%) when the initial substrate concentration was 10 g/L. The production was further investigated using industrially relevant linoleic acid concentrations (100-300 g/L) leading to HPODE yields of similar to 40% and the volumetric productivity 3.6 g/(L h), and a selectivity for 13-(Z,E)-HPODE of around 74%. (c) 2012 Elsevier B.V. All rights reserved.
palavras-chave
UNSATURATED FATTY-ACIDS; SOYBEAN LIPOXYGENASE; IMMOBILIZED LIPOXYGENASE; MANGANESE LIPOXYGENASE; MASS-SPECTROMETRY; OXIDATION; IDENTIFICATION; SYSTEM; STATE; OIL
categoria
Engineering
autores
Villaverde, JJ; van der Vlist, V; Santos, SAO; Haarmann, T; Langfelder, K; Pirttimaa, M; Nyyssola, A; Jylha, S; Tamminen, T; Kruus, K; de Graaff, L; Neto, CP; Simoes, MMQ; Domingues, MRM; Silvestre, AJD; Eidner, J; Buchert, J
nossos autores
Armando Jorge Domingues Silvestre
Professor Catedrático
Carlos Pascoal Neto
Diretor do Raiz
Sónia Andreia Oliveira Santos
Investigador AuxiliarProjectos
agradecimentos
The authors gratefully acknowledge the financial support provided by the European Research Project (Novel enzyme tools for production of functional oleochemicals from unsaturated lipids (ERA-NOEL), ERA-IB/BIO/0001/2008), CICECO (Pest-C/CTM/LA0011/2011) and QOPNA (PEst-C/QUI/UI0062/2011). Juan Jose Villaverde and Sonia A.O. Santos also thank FCT-Fundacao para a Ciencia e a Tecnologia for the awarding of a postdoctoral grant (BPD/UI89/4520/2009) and a Ph.D. Grant (SFRH/BD/42021/2007), respectively. Martti Alkio is thanked for the GPC analyses.