Myceliophthora thermophila M77 utilizes hydrolytic and oxidative mechanisms to deconstruct biomass

Biomass is abundant, renewable and useful for biofuel production as well as chemical priming for plastics and composites. Deconstruction of biomass by enzymes is perceived as recalcitrant while an inclusive breakdown mechanism remains to be discovered. Fungi such as Myceliophthora thermophila M77 appear to decompose natural biomass sources quite well. This work reports on this fungus fermentation property while producing cellulolytic enzymes using natural biomass substrates. Little hydrolytic activity was detected, insufficient to explain the large amount of biomass depleted in the process. Furthermore, this work makes a comprehensive account of extracellular proteins and describes how secretomes redirect their qualitative protein content based on the nature and chemistry of the nutritional source. Fungus grown on purified cellulose or on natural biomass produced secretomes constituted by: cellobiohydrolases, cellobiose dehydrogenase, B-1,3 glucanase, B-glucosidases, aldose epimerase, glyoxal oxidase, GH74 xyloglucanase, galactosidase, aldolactonase and polysaccharide monooxygenases. Fungus grown on a mixture of purified hemicellulose fractions (xylans, arabinans and arabinoxylans) produced many enzymes, some of which are listed here: xylosidase, mixed B-1,3(4) glucanase, B-1,3 glucanases, B-glucosidases, B-mannosidase, B-glucosidases, galactosidase, chitinases, polysaccharide lyase, endo B-1,6 galactanase and aldose epimerase. Secretomes produced on natural biomass displayed a comprehensive set of enzymes involved in hydrolysis and oxidation of cellulose, hemicellulose-pectin and lignin. The participation of oxidation reactions coupled to lignin decomposition in the breakdown of natural biomass may explain the discrepancy observed for cellulose decomposition in relation to natural biomass fermentation experiments.Peer reviewedMicrobiology and Molecular GeneticsBiochemistry and Microbiolog

Second generation ethanol in Brazil: Can it compete with electricity production?

Much of the controversy surrounding second generation ethanol production arises from the assumed competition with first generation ethanol production: however, in Brazil, where bioethanol is produced from sugarcane, sugarcane bagasse and trash will be used as feedstock for second generation ethanol production. Thus, second generation ethanol production may be primarily in competition with electricity production from the lignocellulosic fraction of sugarcane. A preliminary technical and economic analysis of the integrated production of first and second generation ethanol from sugarcane in Brazil is presented and different technological scenarios are evaluated. The analysis showed the importance of the integrated use of sugarcane including the biomass represented by surplus bagasse and trash that can be taken from the field. Second generation ethanol may favorably compete with bioelectricity production when sugarcane trash is used and when low cost enzyme and improved technologies become commercially available. (C) 2011 Elsevier Ltd. All rights reserved.102198964897

Simultaneous production of xylooligosaccharides and antioxidant compounds from sugarcane bagasse via enzymatic hydrolysis

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Advances in industrial biotechnology offer potential opportunities for economic utilization of agroindustrial residues such as sugarcane bagasse, which is the major by-product of the sugarcane industry. Due to its abundant availability and despite the complex chemical composition, it can be considered an ideal substrate for microbial processes for the production of value-added products. In the present study we evaluated the enzymatic production of xylooligosaccharides (XOS) and antioxidant compounds from sugarcane bagasse using XynZ from Clostridium thermocellum, a naturally chimeric enzyme comprising activities of xylanase and feruloyl esterase along with a carbohydrate binding module (CBM6). In order to reveal the biotechnological potential of XynZ, the XOS released after enzymatic hydrolysis using different substrates were characterized by capillary electrophoresis and quantified by high performance anion exchange chromatography. In parallel, the antioxidant capacity related to the release of phenolic compounds was also determined. The results indicated noteworthy differences regarding the amount of XOS and antioxidant phenolic compounds produced, as well as the XOS profile, functions of the pre-treatment method employed. The ability of XynZ to simultaneously produce xylooligosaccharides, natural probiotics, phenolic compounds and antioxidant molecules from natural substrates such as sugarcane bagasse demonstrated the biotechnological potential of this enzyme. Production of value-added products from agro-industrial residues is of great interest not only for advancement in the biofuel field, but also for pharmaceutical and food industries. (C) 2013 Elsevier B.V. All rights reserved.52770775Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)CNPq [474022/2011-4, 310177/2011-1, 142685/2010-0]FAPESP [2008/58037-9, 2011/14200-6, 2012/18859-5, 2013/03061-0