Cinética de crescimento do fungo termófilo Myceliophthora thermophila M. 7.7 em cultivo no estado sólido

• Autor(a) principal: Gomes, Ana Carolina dos Santos [UNESP]
• Data de Publicação: 2015
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://hdl.handle.net/11449/127684
• topic: Tecnologia de alimentos; Enzimas de fungos - Aplicações Industriais - Culturas e meios de cultura; Cinetica de enzimas; Fungos filamentosos

This work aimed to evaluate the growth kinetics of the thermophilic fungus Myceliophthora thermophila M.7.7 during solid-state cultivation (SEC). The immediate application of this kinetics is in heat and mass transfer modeling in SEC bioreactors; however, through the kinetics, the metabolic secretion could be understood and forecasted. The cultivation medium was composed by sugar cane bagasse and wheat bran in the proportion 7:3 and the indirect determination of biomass where done using analytical chemical techniques, as well as through image analysis. The analytical methods were based on the quantification of N-acetylglucosamine, extracellular enzyme activities, and soluble proteins. The digital analysis were performed using a specific software, and the growth quantification was correlated to the superficial area occupied by the microorganism and and through Optical Microscopy (LOM) and Scanning Electron Microscopy (SEM).The glucosamine analysis is considered an adequate method to quantify the microbial growth, since it aloud to clearly identify the phases of fast growing, stationary and decreasing, even though the lag phase identification was uncertain due to the interference of the cultivation medium on the analytical method. The analysis of CMCase, amylases, xylanases and proteases were good indicators of the fungal metabolic activities, but not of the fungal growth. The determination of the content of soluble proteins by Lowry technique presented uncertainties and do not represent faithfully all the microorganism development phases. The growth analysis by SEM possible to describe the morphological characteristics of the fungus, as the presence of conidia and hyphae propagation on fibrils branched from sugar cane bagasse. The digital image processing was well correlated to the analytical methods, but was also discarded as an adequate growth indicator. Nevertheless, this technique is promising ...