Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, Nanjing Agricultural University, Nanjing 210095, China.
Bioresour Technol. 2012 Nov;123:117-24. doi: 10.1016/j.biortech.2012.07.051. Epub 2012 Jul 27.
Multiple acidophilic xylanolytic enzymes were produced by Penicillium oxalicum GZ-2 during growth on wheat straw, rice straw, corn stover, and wheat bran. The expression of xylanase isoforms was dependent on substrate type and nitrogen source. The zymograms produced by the SDS-PAGE resolution of the crude enzymes indicated that wheat straw was the best inducer, resulting in the highest xylanase (115.2U/mL) and β-xylosidase (89mU/mL) activities during submerged fermentation. The optimum temperature and pH for xylanase activity were 50°C and 4.0, respectively; however, the crude xylanase enzymes exhibited remarkable stability over a broad pH range and showed more than 90% activity at 50°C for 30min at pH 4.0-8.0. The results revealed that P. oxalicum GZ-2 is a promising acidophilic xylanase-producing microorganism that has great potential to be used in biofuels, animal feed, and food industry applications.
产黄青霉 GZ-2 在小麦秸秆、水稻秸秆、玉米秸秆和麦麸上生长时会产生多种酸性木聚糖酶。木聚糖酶同工酶的表达依赖于底物类型和氮源。SDS-PAGE 解析粗酶的同工酶图谱表明，小麦秸秆是最好的诱导剂，在液体发酵过程中产生的木聚糖酶（115.2U/mL）和β-木糖苷酶（89mU/mL）活性最高。木聚糖酶活性的最适温度和 pH 值分别为 50°C 和 4.0；然而，粗木聚糖酶在较宽的 pH 范围内表现出显著的稳定性，在 pH 4.0-8.0 下，50°C 处理 30min 后仍保持超过 90%的活性。结果表明，产黄青霉 GZ-2 是一种很有前途的产酸性木聚糖酶的微生物，具有在生物燃料、动物饲料和食品工业应用中的巨大潜力。
