Ng Hui Suan, Chai Cindy Xin Yi, Chow Yin Hui, Loh Wai Leng Carmen, Yim Hip Seng, Tan Joo Shun, Lan John Chi-Wei
Faculty of Applied Sciences, UCSI University, UCSI Heights, 56000 Cheras, Kuala Lumpur, Malaysia.
School of Engineering, Taylor's University Lakeside Campus, 47500 Subang Jaya, Selangor, Malaysia.
J Biosci Bioeng. 2018 May;125(5):585-589. doi: 10.1016/j.jbiosc.2017.12.010. Epub 2018 Jan 12.
Xylanase enzyme degrades linear polysaccharide β-1,4 xylan and the hemicellulose of the plant cell wall. There is a growing demand in finding a cost-effective alternative for industrial scale production of xylanase with high purity for pharmaceutical applications. In this study, an alcohol/salt aqueous biphasic system (ABS) was adopted to recover xylanase from the Bacillus subtilis fermentation broth. The effects of several ABS parameters such as types and concentrations of alcohols and salts (i.e., sulphate, phosphate, and citrate), amount of crude loading and pH of the system on the recovery of xylanase were investigated. Partition coefficient of xylanase (K), selectivity (S) and yield (Y) of xylanase in top phase of the ABS were measured. Highest K (6.58 ± 0.05) and selectivity (4.84 ± 0.33) were recorded in an ABS of pH 8 composed of 26% (w/w) 1-propanol, 18% (w/w) ammonium sulphate. High Y of 71.88% ± 0.15 and a purification fold (P) of 5.74 ± 0.33 were recorded with this optimum recovery of xylanase using alcohol/salt ABS. The purity of xylanase recovered was then qualitatively verified with sodium dodecyl sulphate (SDS) gel electrophoresis. The SDS profile revealed the purified xylanase was successfully obtained in the top phase of the one-step 1-propanol/sulphate ABS with a distinct single band.
木聚糖酶可降解线性多糖β-1,4-木聚糖和植物细胞壁的半纤维素。对于工业规模生产高纯度木聚糖酶用于制药应用而言，寻找一种具有成本效益的替代方法的需求日益增长。在本研究中，采用醇/盐水双相体系（ABS）从枯草芽孢杆菌发酵液中回收木聚糖酶。研究了几种ABS参数，如醇和盐（即硫酸盐、磷酸盐和柠檬酸盐）的类型和浓度、粗酶液加载量和体系pH对木聚糖酶回收的影响。测定了木聚糖酶在ABS上相中的分配系数（K）、选择性（S）和产率（Y）。在由26%（w/w）1-丙醇、18%（w/w）硫酸铵组成的pH 8的ABS中，记录到最高的K（6.58±0.05）和选择性（4.84±0.33）。使用醇/盐ABS以这种最佳回收率回收木聚糖酶时，记录到高产率71.88%±0.15和纯化倍数（P）5.74±0.33。然后用十二烷基硫酸钠（SDS）凝胶电泳对回收的木聚糖酶的纯度进行定性验证。SDS图谱显示，在一步法1-丙醇/硫酸盐ABS的上相中成功获得了纯化的木聚糖酶，呈现出一条清晰的单带。
