Monday, May 4, 2009
5-96
Comparative production and characterization of cellulolitic enzymes from thermophilic fungi Thermoascus aurantiacus CBMAI756 and Thermomyces lanuginosus
Lílian R. Do-Amaral1, Rodolfo Travaini1, Thiago O. P. Pinto1, Gomes, E. Gomes2, and Roberto Da-Siliva1. (1) Chemistry and Environmental Science, UNESP, Rua Cristovao Colombo, 2265, Sao Jose do Rio Preto, Brazil, (2) Biology, São Paulo State University-UNESP/IBILCE, R: Cristovao Colombo, 2265, Jd Nazareth, São José do Rio Preto, 15054-000, Brazil
The thermophilics fungos Thermoascus aurantiacus CBMAI756 and Thermomyces lanuginosus were cultivated in a mixture of sugar cane bagasse and corncob on solid state fermentation for cellulases (endoglucanase, exoglucanase, b-glucosidase) production. The maximum production of endoglucanase, 922 ± 17 U/g, from T. aurantiacus occurred at 120 h of fermentation. The enzyme exhibited optimum pH at 4.0, optimum temperature at 80 °C and remained stable for 24 h at pH range of 4.0 - 9.5 and for 1 h at 60 °C (remaining 75 % of its original activity). This enzyme was not produced by T. lanuginosus. Exoglucanase was not produced by both fungi. The maximum production of b-glucosidase, 77,6 ± 6,0 U/g, by T. aurantiacus occurred at 120 h of fermentation. The enzyme exhibited optimum pH at 4.0, optimum temperature at 75 °C and remained stable for 24 h at pH range 5.0 - 9.0 and for 1 h at 70 °C (remaining 75 % of its original activity). The maximum production of this enzyme, 83,0 ± 1,2 U/g, by T. lanuginosus occurred at 216 h of fermentation. The enzyme exhibited optimum pH at 5.0 - 5.5, optimum temperature at 60 °C and remained stable for 24 h at pH range 5.0 - 10.0 and for 1 h at 50 °C (remaining 75 % of its original activity). These results indicate that the consortiation of these enzyme preparations acting together may be a good strategy to improve hydrolyses of lignocellulosic material in the area of bioenergy.