Estudo da produção de Trichoderma stromaticum em fermentação em substrato sólido

Author(s)

Rodrigo de Oliveira Moraes

• Document type: Doctoral Thesis
• Press: São Paulo. , gráficos, ilustrações, tabelas.
• Institution: Universidade de São Paulo (USP). Conjunto das Químicas (IQ e FCF) (CQ/DBDCQ)
• Defense date: 2004-02-18

Examining board members

Deise Maria Fontana Capalbo; Vanildo Luiz Del Bianchi; Joao Carlos Monteiro de Carvalho; Itamar Soares de Melo; Elias Basile Tambourgi

• Advisor: Deise Maria Fontana Capalbo
• Field of knowledge: Engineering - Chemical Engineering
• Indexed in: Banco de Dados Bibliográficos da USP-DEDALUS
• Location: Universidade de São Paulo. Biblioteca do Conjunto das Químicas; CQ T/660.28449; M827e

Abstract

Bacteria, yeasts and fungi are capable of growing on solid substrates. Amongst these microorganisms, filamentous fungi are the most important for Solid Substrate Fermentation (SSF), owing to their physiological and biochemical properties. Growth at low water activity (aw) and low pH, production of extra-cellular hydrolytic enzymes and sporulation are some of the characteristics of filamentous fungi which make them suitable for SSF. Parameters such as temperature, aw, pH, oxygen levels and concentration of nutrients and products are important in SSF processes. Mass production of Trichoderma sp. has been widely studied in SSF process, to apply it in the control of several phytopathogenic fungi. The species T. stromaticum production is desired for field application to control Crinipellis perniciosa, the agent of a serious fungal disease of cacao, in Latin America, called \"witches\' broom\". The objectives of this work were to study the mass production of T. stromaticum in SSF; to optimize the most important environmental parameters of the system; and to develop a method for biomass estimation through the measurement of dimethyl sulfide (DMS) released during the process. Best results were obtained in tray bioreactor, aw of 0.987, in the dark, and inoculum concentration of 5.0 x 105 spores per gram of moisturized substrate containing wheat bran and oatmeal. The methodology for biomass estimation through the analysis of DMS concentration showed to be simple and accurate. The correlation coefficient between the DMS released and the spore concentration of T. stromaticum was 0.950. (AU)