ORIGINAL ARTICLE Immobilization of inulinase obtained by solid-state fermentation using spray-drying technology GABRIELA P. ZEMOLIN 1 , MICHELE GAZONI 1 , GIOVANI L. ZABOT 1 , SIMONE M. GOLUNSKI 1 , VIVIANE ASTOLFI 1 , VALÉRIA DAL PRÁ 2 , EDSON L. FOLETTO 3 , LUCAS MEILI 3 , MARCELO BARCELLOS DA ROSA 2 , CLARISSA DALLA ROSA 1 , ALTEMIR J. MOSSI 4 , HELEN TREICHEL 4 & MARCIO A. MAZUTTI 3 1 Department of Food Engineering - URI Campus de Erechim, Erechim, Brazil, 2 Laboratory of Chemical Analysis, Department of Chemistry, Federal University of Santa Maria, Santa Maria, RS, Brazil, 3 Department of Chemical Engineering - Federal University of Santa Maria, Santa Maria, Brazil, and 4 Universidade Federal da Fronteira Sul, Erechim - RS, Brazil Abstract This work focuses on the immobilization of a crude inulinase extract obtained by solid-state fermentation using spray- drying technology. Maltodextrin and arabic gum were used as immobilizing agents. The effects of inlet air temperature, maltodextrin/arabic gum ratio and mass fraction of crude enzyme extract on the activity of immobilized inulinase were assessed using a central composite rotatable design (CCRD) (2 3 ). The optimum operational conditions for the immobili- zation of inulinase by spray-drying was obtained at an inlet air temperature of 200°C, mass fraction of crude enzyme extract of 0.5 wt% and using only arabic gum as immobilizing agent. The immobilized enzyme had good thermostability, comparable with other inulinases obtained from different microorganisms. The method used gave good enzyme activity after immobilization and could be applied to other enzymes which have good thermal stability. Keywords: inulinase, spray-drying, immobilization Correspondence: Prof. Marcio A. Mazutti, D.Sc., Federal University of Santa Maria, Chemical Engineering, Av. Roraima, 1000, Santa Maria, 97105-900 Brazil. Tel: + 55-55-3220-9592. E-mail: mazutti@ufsm.br (Received 8 November 2011; accepted 23 July 2012) Introduction Enzyme-catalysed processes are useful alternatives to conventional process technology in industrial and analytical fields. Unlike chemical catalysts, biological systems can accomplish complex chemical conver- sions under mild environmental conditions with high specificity and efficiency. Biological systems can help in ingredient substitution, processing aid substitu- tion, increasing process efficiency, reducing undesir- able products, increased plant capacity, increasing product yields and improving product profiles. The variety of chemical transformations catalysed by enzymes has made these catalysts a prime target of exploitation by the emerging biotechnology industries (D’Souza 1999). Immobilization techniques have been used to enhance enzyme stability and also to aid recovery and reutilization. For industrial processes, several immobilization methods have been studied. A process that yields an active and stable enzyme, retaining good substrate specificity generally eliminates most of the disadvantages of using enzymes, making their use in industrial processes practical (Richetti et al. 2011). Spray-drying processes are used to dry pharma- ceuticals, fine chemicals, foods, dairy products, blood plasma, numerous organic and inorganic chemicals, rubber latex, ceramic powders, deter- gents and other chemicals. This technique has sev- eral advantages such as: heat-sensitive materials can be dried at atmospheric pressure and at low temperatures; the spray-drying process permits large scale production in continuous operation with relatively simple equipment; and spray-dried products are relatively homogenous (Isono et al. 1995; Oliveira et al. 2009). Biocatalysis and Biotransformation, 2012; Early Online: 1–8 ISSN 1024-2422 print/ISSN 1029-2446 online © 2012 Informa UK, Ltd. DOI: 10.3109/10242422.2012.715635 Biocatal Biotransformation Downloaded from informahealthcare.com by Universidade Federal de Santa Maria on 08/16/12 For personal use only.