Atividade enzimática de fungos filamentosos voltada à aplicação em processos de geração de bioetanol

• Autor(a) principal: Lima, Lidiane Maria dos Santos [UNIFESP]
• Data de Publicação: 2015
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UNIFESP
• dARK ID: ark:/48912/001300000xm6m
• Texto Completo: https://sucupira.capes.gov.br/sucupira/public/consultas/coleta/trabalhoConclusao/viewTrabalhoConclusao.jsf?popup=true&id_trabalho=2625922; https://repositorio.unifesp.br/handle/11600/47189
• topic: Ligninases; Cellulases; Mono-oxygenases; Composting; Proteases; Ligninases; Celulases; Mono-oxigenases; Compostagem; Proteases

The search for mesophilic and thermophilic filamentous fungi isolated from various environments, as well as waste treatment processes such as composting, represents an appropriate strategy to obtain microbial enzymes, due to the high temperatures at which such processes occur. Furthermore, habitats are promising as regards the recovery of micro-organisms and with potential metabolic capacities of interest. This study investigated the enzyme potential of fungi isolated from the filter cake compost (by-product of the processing of sugarcane) plus soil samples from the Atlantic Forest and / or pruning waste ground in the interest of detecting and evaluating the enzymatic activity of hydrolases and oxidoreductases, for future use in cellulosic ethanol production processes. Approximately 200 different fungal strains (macro / microscopically) were isolated and subjected to determination of cellulolytic activity using the kit AZO-CM-Cellulose S-ACMC 04/07 (Megazyme®) for screening tests of cellulolytic action. In this initial screening, 13 isolates were selected as positive hits: FPZ_SP3 01, SP3 05, SP3 47, SP3 72, SP3 74, SP3 75, SP3 91, SP2 121, SP1 129, SP1 135, SP1 141, SP1 148 and SP1 151. Such fungi followed for new enzymatic assays aimed at the detection and quantification of the active cellulolytic complex (FPase test) as well as evaluation of ligninases activities, proteases, chitinases and mono-oxygenase. The selected isolates were also subjected to taxonomic characterization analyzes, using phenotypic and molecular techniques. The results obtained in this study suggested that the isolated SP3 01 (0.123 FPU /ml), SP3 75 (0.085 FPU /ml); SP3 74and SP2 121 (0.084 FPU /ml), when the pH conditions are 4.8 efficient producers of cellulolytic enzymes. With regard to the proteolytic activity, three isolates (SP3 01, SP3 72 and SP1 135) were selected, suggesting the presence of metallo proteases and serine proteases. As for chitinolytic activity, 12 isolates demonstrated promising enzyme activities for exoquitinase, quitobiosidase and endochitinase. Under-oxide reductase, it was possible to identify four isolates SP3 47, SP3 75, SP1 129 and SP1 141 with ligninolytic activity. The isolated SP3 05 was selected with mono-oxygenase activity induced by the presence of PAHs (polyaromatic hydrocarbons). Regarding the characterization of isolates, the phenotypic and molecular techniques allowed the taxonomic identification of Aspergillus niger (SP3 01), Mucor sp. (SP3 47), Aspergillus niger (SP3 74), Trichoderma koningii (SP3 75), Geotrichium candidum (SP3 91) Byssochlamys nivea (SP1 129), Paecilomyces saturatus (SP1 141), Aspergillus fumigatus (SP1 148) and Aspergillus fumigatus (SP1 151). Thus, isolated from the filter cake compost were efficient producers of hydrolytic enzymes and oxidative of interest to future enforcement in re-use of lignocellulosic waste processes to the production of second generation ethanol.