Production of Cellulase and Xylanase by Cellulomonas flavigena immobilized in Sodium Alginate in Bubble Column Reactors

Production of Cellulase and Xylanase by Cellulomonas flavigena immobilized in Sodium Alginate in Bubble Column Reactors

S358 Special Abstracts / Journal of Biotechnology 150S (2010) S1–S576 Furthermore, this methodology permits the coating of all negative charges pres...

159KB Sizes 1 Downloads 61 Views

S358

Special Abstracts / Journal of Biotechnology 150S (2010) S1–S576

Furthermore, this methodology permits the coating of all negative charges presented on the enzyme surface, an advantage compared with the immobilization of the enzyme on agarose modified with PEI, where the enzyme is oriented by the riches area of negative charges on the surfaces and this could cause several subpopulations if the enzyme presents several rich areas on these residues on the surface. Therefore, due to the simplicity and short time-consuming of these modifications (performed in solid phase on an immobilized enzyme), this strategy seems to be a promising alternative and compatible with the rest of techniques in biocatalysis to develop new enantioselective biocatalysts. References Montiel, C., Bustos-Jaimes, I., 2008. Curr. Chem. Biol. 2, 50–59. Siddiqui, K.S., Parkin, D.M., Curmi, P.M.G., et al., 2009. Biotechnol. Bioeng. 103, 676–686. Mateo, C., Palomo, J.M., Fernandez-Lorente, G., Guisan, J.M., Fernandez-Lafuente, R., 2007. Enzyme Microb. Technol. 40, 1451–1463.

Fig. 1. Extracellular protein production.

doi:10.1016/j.jbiotec.2010.09.411 [P-I.46] Production of Cellulase and Xylanase by Cellulomonas flavigena immobilized in Sodium Alginate in Bubble Column Reactors O.A. Rojas-Rejón 1 , E. Cristiani-Urbina 2,∗ , H.M. Poggi-Varaldo 1 , A.C. Ramos-Valdivia 1 , A. Martínez-Jiménez 3 , T. Ponce-Noyola 1 1

Centro de Investigación y de Estudios Avanzados, IPN, Mexico Escuela Nacional de Ciencias Biológicas, IPN, Mexico 3 Instituto de Biotecnología, UNAM, Mexico Keywords: Immobilized Cellulomonas flavigena; Cellulase and Xylanase Production; Packed-Bed and Fluidized-Bed Reactors; Bubble Column Reactor 2

Introduction: Plant biomass has emerged as a renewable source of energy. Sugars contained in lignocellulosic wastes can be used as carbon source for a countless number of bioprocess. Chemical and physical treatments have disadvantages such as high costs, drastic operation conditions, specialized equipment and residual inhibitory compounds. The enzymatic hydrolysis with cellulase and xylanases yields monosaccharide from lignocellulosic wastes. Biological treatment with these enzymes can reduce costs by operating under standard conditions and reduces the formation of inhibitory compounds. The aim of this work was to evaluate a system of immobilized cells in two different reactor configurations for the best production of cellulases and xylanases. Methods: The immobilization technique was according to Barroco-Florido et al. (2001) with some modifications. Immobilized cells were grown in 1% CMC as substrate in a bubble column reactor at optimum conditions (37 ◦ C, pH 7, 1 vvm). Packed bed column and fluidized bed column reactors were used to growth

Fig. 2. Xylanase (䊉) and CMCase (♦) activity produced in Packed Bed (䊉) and Fluidized Bed reactors (♦).

and produce enzymes. Protein was determined according to Lowry method. Xylanase and CMCase activities were measured by the releasing reducing sugars using DNS method. Results: The production of extracellular protein was similar in both reactors and after 120 h cultures reached the same level of production that that observed in control culture (free cells) (Fig. 1). The specific activity of xylanase and CMCase were higher in the fluidized bed reactor than in the packed bed reactor (Fig. 2). Discussion: Down streams processes and purification of materials of great importance such as enzymes and industrial metabolites requires cell separation. Cell immobilization of Cellulomonas flavigena allows the complete separation of enzymes from cells. The best performance in enzyme production and activity was the Fluidized Bed Reactor. doi:10.1016/j.jbiotec.2010.09.412

Scheme 1.