Purification strategies of Scytalidium thermophilum xylanase

Xylanase (E.C.3.2.1.8) is an enzyme which hydrolyses b-1,4 bonds in xylan backbone which consists of D-xylose molecules. Based on its function, xylanase is used in many industries. For animal feed, paper production and textile industry partially purified xylanase can be acceptable, but for bakery and beverage industry, chemical or pharmaceutical applications, high purity is generally required. In this study, xylanase was produced from a thermophilic fungus, Scytalidium thermophilum and purification strategies were developed for industrial and analytical purposes. In addition, within the cost reduction approach, corn cobs are used as carbon source in the culture medium which are produced millions of tons as agricultural waste each year and have very low economical value. Partial purification of xylanase was studied with ammonium sulphate precipitation (ASP), aqueous two phase system (ATPS) and ultrafiltration (UF). Precipitation with the usage of 50% (v/v) ammonium sulphate concentration gave the best results as 2.5 fold purification and 52% yield. TX-114 was employed at a concentration of 7% (v/v) for ATPS and 2.7 fold purification with 79% yield was obtained. Three-step UF technique was practiced using membranes with different MWCO values; which were 100, 30 and 10 kDa, sequentially. As the result of this technique, 4.3 fold purification with 25% yield was attained. With these results, partially purified xylanase can be presented as an ingredient for industrial applications. For analytical purification of enzyme