Production, extraction and stability of lignocellulolytic enzymes for use in degradation of pollutant compounds

Author(s)

Gleison de Souza

• Document type: Master's Dissertation
• Press: Piracicaba.
• Institution: Universidade de São Paulo (USP). Centro de Energia Nuclear na Agricultura (CENA/STB)
• Defense date: 2012-09-21

Examining board members

Regina Teresa Rosim Monteiro; Sandra Helena da Cruz; Eleni Gomes

• Advisor: Regina Teresa Rosim Monteiro

Abstract

Due to the convenience of using enzymes in the processing of products, technology development of enzymatic processes and its use are growing in the industry because of numerous applications in various sectors of economic and health importance. The fungi of the genus Pleurotus synthesize a variety of lignocellulolytic enzymes that has the potential to degrade / transform various polymeric compounds, including vinasse originating from the sugar industry. The proposal is to evaluate lignocellulolytic enzymes such as laccase, peroxidase and MnP, synthesized by the fungi P. sajor-caju CCB 020, P. ostreatus and P.albidus CCB 068 cultivated in vinasse and /or sugarcane bagasse moistened with vinasse. The activity of these extracellular enzymes was evaluated every three days for 30 days with regard to stability in relation to time and related to the degradation ability of the indigo dye. The cultivation of the fungi was performed at 28°C in incubators, with stirring of vinasse in nature, and the solid medium was stationary. After culturing, the supernatant or the enzyme solution extracted from the solid medium with citrate buffer was used. Decolorization of the indigo dye was tested in solution at 0.02% at pH 4.5 and 35 °C temperature. The activities varied according to the culture medium and the strains. Laccase had peaks of activity between the 12th and 15th days with values ranging from 384 to 1463 UI L-1, in the liquid and solid medium with peaks at the 6th day of culture, with values ranging from 4 a 40 UI L-1. Peroxidase activity peaked at the 12th, 15th and 21st days of cultivation, according to the strain of the fungus and activities from 356 to 975 UI L-1. The MnP activity peaked at the 12th and 18th days and had peak activities from 2.24 to 174 IU L-1. The specific activity P. sajor-caju CCB 020 produced laccase and MnPmore efficiently when compared with the other strains, whereas P. albidus, produced peroxidases more efficiently. Cultivation in vinasse in nature was more efficient than cultivation in solid medium with sugar cane bagasse. The stabilities of the enzymaticactivities varied with the strain of the fungus, cultivation time and the storage time of 1, 2 and 24 h at room temperature. The indigo decolorization was related to the enzymatic activity of laccase and MnP for the strain of the fungus P. sajor-caju CCB 020. However, Pleurotus showed decolorization of vinasse, and it was noticed that P. sajor-caju CCB 020 showed greater potential for vinasse decolorization, about 70%, compared to the others that had lower results. The vinasse decolorization with respect to the absorbance is read at 680 nm. Both fungi inoculated in medium containing vinasse + bagasse had better results on the 3rd ,6th, 9th, 12th, 21st and 30th days, except on the 15th and 18th days when the medium with vinasse alone had better results in both wavelengths (\'lâmbda\'). The P. sajorcaju CCB 020 inoculated in the vinasse + bagasse medium was better on the 9thand 12th days, in the efficiency of decolorization of the dye with 83.56% to 77.56% of the results, for P. ostreatus it was better on the 6th and 12th days in decolorization of the dye with 46.09% and 46.18% respectively, while for P. albidus CCB 068 the result was on the 6th and 9th days (56.23% and 57.42%) (AU)

• FAPESP's process: 09/12390-2 - Production, extraction and stability of lignocellulolytic enzymes for using in degradation of polluents compounds
• Grantee: Gleison de Souza
• Support Opportunities: Scholarships in Brazil - Master