Process Biochemistry 48 (2013) 1188–1196 Contents lists available at SciVerse ScienceDirect Process Biochemistry jo u r n al homep age: www.elsevier.com/locate/procbio A novel thermostable cellulase free xylanase stable in broad range of pH from Streptomyces sp. CS428 Pradeep G.C. a,1 , Yun Hee Choi a,1 , Yoon Seok Choi a , Chi Nam Seong b , Seung Sik Cho c , Hyo Jeong Lee d , Jin Cheol Yoo a,∗ a Department of Pharmacy, Chosun University, Gwangju 501-759, Republic of Korea b Department of Biology, College of Natural Sciences, Sunchon National University, Sunchon, Jeonnam 540-742, Republic of Korea c Department of Pharmacy, College of Pharmacy, Mokpo National University, Muan, Jeonnam 534-729, Republic of Korea d Department of Alternative Medicine, Gwangju University, Gwangju 503-703, Republic of Korea a r t i c l e i n f o Article history: Received 14 November 2012 Received in revised form 29 May 2013 Accepted 1 June 2013 Available online 10 June 2013 Keywords: Xylanase Single-step purification Agro-waste Xylooligosaccharides a b s t r a c t A cellulase free thermostable xylanase from Streptomyces sp. CS428 was isolated from a Korean soil sam- ple, purified by single-step chromatography, and biochemically characterized. The extracellular xylanase was purified 26 fold with a 55% yield by CM Trisacryl cation exchange chromatography. The molecular mass of the enzyme (Xyn428) was approximately 37 kDa. Xyn428 was found to be stable over a broad pH range (4 to ∼13.6) and to 50 ◦ C and have an optimum temperature of 80 ◦ C. Xyn428 had K m and V max values of 102.3 ± 1.2 mg/mL and 3225.4 ± 15 mmol/min mg, respectively, when beechwood xylan was used as substrate. N-terminal sequence of Xyn428 was INRTDHNENSYLEIHNNEAR. CS428 was grown on different agro waste xylan and produced 4197.1 U/mL of xylanase activity in 36 h of cultivation in wheat bran without supplements. Xyn428 activity was inhibited by Tris salt at concentrations above 20 mM, and produced xylose and xylobiose as major products. It was found to degrade agro waste materials by small unit of enzyme (20 U/g) as shown by electron microscopy. As being simple in purification, thermo tolerant, pH stability in broad range and ability to produce xylooligosaccharides show that Xyn428 has potential applications in industries as a biobleaching agent and for xylooligosaccharides production. © 2013 Elsevier Ltd. All rights reserved. 1. Introduction Lignocellulosic biomass includes cellulose (35–50%), hemicel- lulose (20–35%) and lignin (10–25%). Xylan is the major plant hemicellulose, which constitutes 20–40% of total plant biomass [1,2]. Xylan consists of a backbone of -1,4-linked d-xylose residues having arabinose, glucuronic acid, and/or mannose substitutes. A wide variety of microorganisms including aerobic and anaero- bic, mesophiles and thermophiles can produce enzymes that can degrade xylan [2]. The enzymatic hydrolysis of xylan requires the cumulative actions of endo--1,4-xylanase (EC 3.2.1.8), - xylosidase (EC 3.2.1.37), and a series of enzymes that degrade side chain groups. Among these, endo--1,4-xylanase is the most cru- cial enzyme that cleaves glycosidic bonds to produce short chain xylooligosaccharides of various lengths [3]. Xylooligosaccharides productions from commercial and waste xylan were well reported [4,5]. Industrial waste materials have become a global challenge and remained as centre of attraction since they create pollution and unnecessarily occupy space and requires high cost for proper ∗ Corresponding author. Tel.: +82 62 230 6380; fax: +82 62 227 3963. E-mail address: jcyu@chosun.ac.kr (J.C. Yoo). 1 Both authors contributed equally to this work. management. Thus, the production of value added products, such as, bioethanol and oligosaccharides, offers an attractive solution. Bioethanol production includes two steps, that is, the hydrolysis of biomass to sugar and the fermentation of sugar to alcohol. Further- more, the alcohol produced by the hydrolysis of industrial waste materials offers an alternative option of limited fossil fuels. In addi- tion, to remove lignin, paper and pulp industries are using xylanase to degrade xylan, which becomes unfriendly to chemical process [6]. In recent days xylanase production using microbes is pop- ular because of its significant role in food, animal feed, pulp, and paper industries [7]. In particular, xylan degrading enzymes from Streptomyces are being increasingly reported, such as, from Streptomyces lividans [8], Streptomyces sp. 7b [9], Streptomyces cyaneus SN32 [5], Streptomyces rameus L2001 [4], Streptomyces thermocyaneociolaceus [10]. Here, we describe the isolation and identification of a potent xylanase producer – Streptomyces sp. CS428. Further purification by single-step column chro- matography and characterization of an industrially applicable xylanase from this strain were also performed. Apart from this we have compared the activity and stability of xylanase from CS428 with the commercially available xylanase from Ther- momyces lanuginosus, and endo-1,4--xylanase from Trichoderma longibrachiatum. 1359-5113/$ – see front matter © 2013 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.procbio.2013.06.007