PROIMI   05436
PLANTA PILOTO DE PROCESOS INDUSTRIALES MICROBIOLOGICOS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Time-course of an hydrolytic and synthetic lipase activity from Aspergillus niger MYA 135
Autor/es:
ROMERO CINTIA MARIANA; SIVILA CLAUDIA ANALIA; BAIGORI MARIO D.; PERA LICIA MARIA
Reunión:
Simposio; VII( Workshop on Biocatalysis and Biotransformation 1° Simposio Latinoamericano de Biocatalisis y Biotransformaciones; 2014
Resumen:
Keywords: Lipase, synthesis and hydrolysis time-course INTRODUCTION Filamentous microorganisms are good producer for many enzymes or microbial proteins production with industrial application (1, 2, 3). The goal of this research was to study both, the production of a mycelium-bound lipase activity and its chain-length selectivity by using conventional and nonconventional systems. RESULTS AND DISCUSSION When the microorganism begins the exponential phase, the sugar was exhausted in the culture medium (between 24 and 48 h). The maximum yield of biomass concentration was observed at 72 h (3.42 ± 0.18 g /l) (Fig. 1). The sharp drop of sugar could be associated with the increased of biomass. The time-course for hydrolytic lipase activities (using p-NPP, C16 or pNPL C12) are shown in Fig. 2. In aqueous system, the maximum activities were observed in two peaks, at 72 h (Lipase I) and 96 h (Lipase II). The presence of two peaks of activities could be due to the production of two different lipases. The Lipase activity I could be a specific lipase, while Lipase activity II could be a non-specific lipase. In organic system (n-hexane), the hydrolytic activity showed a peak at 86 h with C16. However, the higher activity was observed with C12 at 96 h. Thus, the lipase activity in organic system showed a preference for C12. The time-course for transesterification activities was evaluated by the synthesis of ethyl and butyl palmitate or laurate (Fig. 3). Two peak of transesterification activities were observed in presence of ethanol, at 72 h and 108 h. Both, showed a better performance in the synthesis of ethyl palmitate (p=0.01). The peak of transesterification activity for the synthesis of butyl palmitate was observed at 48 h, while for butyl laurate it was observed at 60 h, showing higher specificity toward C12. CONCLUSION Aspergillus niger MYA 135 exhibited at least two lipases activities in aqueous and organic system with hydrolysis and synthesis capacity. They are a promissory biocatalyst for biodiesel production. ACKNOWLEDGEMENTS This work was supported by PICT-2012-2974 and PICT 2011-2158. REFERENCE 1-Guang J, Bierma TJ (2010) ISTC Rep. Illinois Sustainable Technology Center . 2- Romero CM, Baigori MD, Pera LM (2007) Appl Microbiol Biotechnol 76:861 3- Teng, Y, Xu Y, Wang D (2009) Bioprocess and Biosyst. Eng., 32: 397