Biochemical Characteristics of Penicillium crustosum FP 11 Xylanase II and an Assessment of the Properties of Xylanases Produced by the Genus Penicillium

Penicillium crustosum FP 11 produces two extracellular xylanase, which are designated xylanase I and II, and are induced by corn stover. In this work, xylanase II was purified 40-fold with a recovery yield of 9.2% using DEAE-Sephadex and Sephadex G-75 gel filtration, and the biochemical characteristics of the enzyme were compared with other xylanases produced by the genus Penicillium. Xylanase II exhibited a single band on SDS–PAGE, and had an apparent molecular mass of 28 kDa. The optimal temperature and pH of xylanase II activity were 50ºC and 5.5, respectively. Xylanase II had activities of 61, 53 and 55% in the presence of Mg2+, DTT and β-mercaptoethanol, respectively; however, the enzyme was strongly inhibited by 5 mM Cu2+, EDTA, and SDS. Hydrolysis of beechwood xylan released mainly xylose and short-chain xylo-oligosaccharides as final products. Thus, an assessment of the enzymatic properties of xylanase II showed that its biochemical characteristics are best suited for the saccharification of lignocellulosic biomass into fermentable sugars.