Aachary Ayyappan Appukuttan, Prapulla Siddalingaiya Gurudutt
Fermentation Technology and Bioengineering Department, Central Food Technological Research Institute, Mysore 570 020, Karnataka, India.
Bioresour Technol. 2009 Jan;100(2):991-5. doi: 10.1016/j.biortech.2008.06.050. Epub 2008 Aug 13.
Comparison of various pretreatments such as mild alkali/acid treatments and pressure cooking of corncob to expose its lignin-saccharide complex has been carried out to enhance enzymatic hydrolysis of xylan to xylooligosaccharides (XOS). Scanning electron micrographs of lignin-saccharide complex of native and pretreated corncob powder showed that the complex was greatly altered during alkali pretreatment. Hydrolysis of alkali pretreated corncob powder using a commercial endoxylanase produced 81+/-1.5% of XOS in the hydrolyzate equivalent to 5.8+/-0.14 mg ml(-1) of XOS. Reaction parameters for the production of XOS from corncob using endoxylanase from Aspergillus oryzae MTCC 5154 were optimized and an XOS yield of 10.2+/-0.14 mg ml(-1) corresponding to 81+/-3.9% with 73.5% xylobiose was obtained. HPLC/RID and ESI/MS analysis of XOS mixture and purified fractions showed that XOS was a mixture of neutral oligosaccharides of DP, 2-7.
为了提高木聚糖向低聚木糖（XOS）的酶促水解效率，已对各种预处理方法进行了比较，如轻度碱/酸处理以及对玉米芯进行加压蒸煮以暴露其木质素 - 糖类复合物。天然和预处理玉米芯粉末的木质素 - 糖类复合物的扫描电子显微镜图像显示，在碱预处理过程中该复合物发生了很大变化。使用商业内切木聚糖酶对碱预处理的玉米芯粉末进行水解，水解产物中XOS的含量为81±1.5%，相当于5.8±0.14 mg ml⁻¹的XOS。对米曲霉MTCC 5154的内切木聚糖酶从玉米芯生产XOS的反应参数进行了优化，获得了10.2±0.14 mg ml⁻¹的XOS产量，相当于81±3.9%，其中木二糖含量为73.5%。对XOS混合物和纯化馏分的HPLC/RID和ESI/MS分析表明，XOS是DP为2 - 7的中性寡糖混合物。
