Supplementation of commercial cocktail with endo-arabinanase of Bacillus licheniformes 
Monday, April 28, 2014
Exhibit/Poster Hall, lower level (Hilton Clearwater Beach)
Carla Botelho-Machado1, Ana Paula Citadini1, Rosana Goldbeck1, Zaira Bruna Hofmam1, Evandro Antônio de Lima1, Fernanda Lopes Figueiredo1, Tony Márcio da Silva2, Maria de Lourdes Teixeira de Moraes Polizeli2, Roberto Ruller1 and Richard John Ward1, (1)Ctbe, Laboratório Nacional de Ciência e Tecnologia do Bioetanol - CTBE/CNPEM, Campinas, Brazil, (2)Biology, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo (USP), Ribeirão Preto, Brazil
An essential step in the conversion of lignocellulosic biomass to ethanol or other by-products biorefinery is the depolymerization of polysaccharides constituents to fermentable sugars by enzymatic pathway. Polysaccharides containing L-arabinose residues are found as constituents of plant cell walls.  They are found as either homoglycans, arabinans or heteroglycans such as arabinoxylans and arabinogalactans. Arabinanases (ABNA) are one of the enzymes responsible for hydrolase arabinan. The aim of this work was to evaluate the supplementation of commercial enzyme cocktail Cellic with endo-arabinanase of Bacillus licheniformes.  For this purpose the enzyme was cloned and expressed in E. coli system and the biochemistry and biophysical characterization was performed. The results indicate that the catalytic activity of the enzyme was enhanced in the presence of divalent ions and are strongly inhibited by Cu2+, Zn2+ e Fe3+ (5 mM). The optimum pH and temperature range for activity were 5.5 to 6.5 and 35 to 40 ˚ C, respectivelly. The enzyme was able to increase by 15% the hydrolysis of cane sugar biomass when supplemented to Cellic cocktail despite support only 1 hour at 50 °C .  The enzyme stability was increased in 128 times when immobilized with glyoxyl agarose. So, arabinanase demonstrate the importance of pectin side chains hydrolysis when compared to cocktail without supplementation.