科研之友
微信
新浪微博
Facebook
分享链接
摘要
Carboxymethyl cellulase (CMCase) hydrolyses cellulose into glucose and is useful in various industrial applications. Conventional CMCase purification methods are rather complicated and time-consuming; thus, a cost-effective strategy for CMCase recovery is on demand. Polyethylene-glycol (PEG)/sodium citrate aqueous biphasic system (ABS) was adopted in this study to investigate the effectiveness of the ABS in the recovery of extracellular Bacillus subtilis CMCase from fermentation broth. Comprehensive optimization steps were executed that took into consideration the ABS variables of PEG molecular weight, tie-line length (TLL), volume ratio (V-R), crude loading, pH and the addition of sodium chloride (NaCl). A CMCase recovery yield (Y-B) of 88.82% +/- 0.69, a purification fold (P-F) of 4.8 and a partition coefficient (K) of 0.44 +/- 0.03 were achieved from the bottom phase of the PEG 6000/citrate ABS with TLL of 42.16% (w/w), V-R of 0.29, 1% of (w/w) NaCl, pH 7.0, and 20% (w/w) crude loading. CMCase was mainly segregated to the salt-rich bottom phase because of the hydrophilicity of the enzyme surface. The highly effective recovery technique was further confirmed by SDS-PAGE analysis. Overall, the present study suggests that the ABS is a potential purification strategy for extracellular CMCase.
- 出版日期2017-7
