Please cite this article in press as: Chapla, D., et al., Characterization of purified fungal endoxylanase and its application for production of value added food ingredient from agroresidues. Food Bioprod Process (2013), http://dx.doi.org/10.1016/j.fbp.2013.08.005 ARTICLE IN PRESS FBP-430; No. of Pages 11 food and bioproducts processing x x x ( 2 0 1 3 ) xxx–xxx Contents lists available at ScienceDirect Food and Bioproducts Processing j ourna l ho me page: www.elsevier.com/locate/fbp Characterization of purified fungal endoxylanase and its application for production of value added food ingredient from agroresidues Digantkumar Chapla, Sejal Dholakiya, Datta Madamwar, Amita Shah ∗ BRD School of Biosciences, Sardar Patel Maidan, Satellite Campus, Post Box No. 39, Sardar Patel University, Vallabh Vidyanagar 388 120, Gujarat, India a b s t r a c t Xylanase from Aspergillus foetidus MTCC 4898 was purified using ammonium sulphate fractionation followed by ion exchange and gel permeation chromatography with 12.26-fold purity and 29.9% recovery. Purified xylanase was found to be 29.9 kDa. Optimum temperature and pH for xylanase activity of purified xylanase were found to be 50 ◦ C and 5.3 respectively. Presence of additives like polyethylene glycol, sodium azide, Tween 80, KCl and NaCl increased the stability of purified xylanase by 35, 29, 28, 32 and 43% respectively at 50 ◦ C after 180 min. Kinetic parameters like K m and V max were found to be 4 mg/ml and 7288 mol/mg/min respectively. The purified xylanase was found to be an endoxylanase as it produced only xylooligosaccharides (XOS) from birchwood xylan. Production of XOS was carried out from xylan extracted from agro-residues using -xylosidase free xylanase. Maximum yield of XOS was 7.28 ± 0.14 mg/ml and 4.52 ± 0.21 mg/ml from wheat straw xylan and rice straw xylan respectively. XOS mixture was suitable for food industry looking at its high thermal stability at low pH. Prebiotic effect of XOS was evaluated by in vitro fermentation of XOS using known probiotic strains of Bifidobacterium spp. © 2013 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved. Keywords: Endo-xylanase; Aspergillus foetidus MTCC 4898; Xylooligosaccharides; Prebiotics 1. Introduction Importance of microbial xylanases have increased in present scenario due to its immense biotechnological applications in mainly food, animal feed, paper and pulp industries as well as for bioconversion of lignocellulosic waste into value-added products (Beg et al., 2001). Xylan is the major constituent of hemicellulose and stands as the second most abun- dant renewable resource on earth after cellulose. Microbial xylanases (E.C. 3.2.1.8) are the preferred catalysts for xylan hydrolysis due to their high specificity, mild reaction condi- tions, negligible substrate loss and no side product generation (Kulkarni et al., 1999). The complete enzymatic degradation of xylan requires the action of a set of enzymes such as endo-xylanase, ˇ-xylosidase, -l-arabinofuranosidase, acetyl xylan esterases. Endo-xylanase is the key enzyme for the hydrolysis of xylan backbone in a random manner producing ∗ Corresponding author. Tel.: +91 2692 234412x114; fax: +91 2692 231042. E-mail addresses: digant chapla@yahoo.co.in (D. Chapla), arshah02@yahoo.com (A. Shah). Received 14 March 2013; Received in revised form 25 July 2013; Accepted 3 August 2013 xylooligosaccharides of variable length ranging from 2 to 10 (Chithra and Gudipati, 2010). Filamentous fungi are interest- ing producers of this enzyme from an industrial point of view due to extracellular release of xylanases, higher yield com- pared to yeast and bacteria and production of several auxiliary enzymes that are necessary for debranching of the substituted xylans (Haltrich et al., 1996). The huge amount of residual plant biomass consid- ered as “waste” can potentially be used to produce various value added products like biofuels, animal feeds, chemicals, enzymes. Utilization of these materials for industrial purpose not only solves the problem of disposal, but also provides an additional income to the farmers (Aachary and Prapulla, 2009). Wheat straw, rice straw, corncobs, tobacco stalk, etc., are rich in hemicellulose and are considered as potential feed stocks for the bioconversion into valuable products like xylooligosac- charides (XOS) and fermentable sugars. 0960-3085/$ – see front matter © 2013 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.fbp.2013.08.005