Production and characterization of endo-polygalacturonase from Aspergillus niger in solid-state fermentation in double-surface bioreactor

• Autor(a) principal: Hendges,Diogo Henrique
• Data de Publicação: 2011
• Outros Autores: Montanari,Queli, Malvessi,Eloane, Silveira,Mauricio Moura da
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Brazilian Archives of Biology and Technology
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132011000200005
• topic: Aspergillus niger; double-surface bioreactor; endo-polygalacturonase; solid-state fermentation; enzyme stability

Endo-polygalacturonase (endo-PG) production by Aspergillus niger T0005/007-2 in solid medium with 170 mm of height was evaluated in a cylindrical double surface bioreactor in 96-h experiments. Cell concentration close to 92 mg.g -¹ dm (mg per g of dry medium) in the standard condition (static) was achieved, whereas in tests under forced aeration of 1.4 and 2.8 L.min-1. Kg-1 mm (L of air per minute per Kg of moist medium) and with the central shaft fungal biomass attained approximately 100 mg.g-1 dm. Superior endo-PG activity was obtained with the central-shaft system, 78 U.g-1 dm (units per g of dry medium). Forced aeration and pressure pulse showed no positive effect on the production of endo-PG, 45 U.g-1 dm and 28 U.g-1 dm, respectively. None of the conditions evaluated was efficient for medium temperature control. Endo-PG was stable up to 40ºC. The activity decreased in 50% after 120 minutes at 50ºC, which is a temperature normally found during this process.