de Sena Amanda Reges, Barros Oliveira Flávio Manoel, Campos Leite Tonny Cley, Evaristo da Silva Nascimento Talita Camila, Moreira Keila Aparecida, de Assis Sandra Aparecida
a Microbiology Laboratory , Federal Institute of Education, Science and Technology of Pernambuco , Barreiros , Brazil.
b Biotechnology Laboratory , Garanhuns Academic Unit, Federal Rural University of Pernambuco , Garanhuns , Brazil.
Prep Biochem Biotechnol. 2017 Oct 21;47(9):945-951. doi: 10.1080/10826068.2017.1365249. Epub 2017 Aug 31.
The aims of the current study are to assess the influence of polyethylene glycol (PEG) concentration, molar mass, pH, and citrate concentrations on aqueous biphasic systems based on 2 factorial designs, as well as to check their capacity to purify tannase secreted by Aspergillus tamarii URM 7115. Tannase was produced through submerged fermentation at 26°C for 67 h in Czapeck-Dox modified broth and added with yeast extract and tannic acid. The factorial design was followed to assess the influence of PEG molar mass (M 600; 4,000 and 8,000 g/ mol), and PEG (C 20.0; 22.0 and 24.0% w/w) and citrate concentrations (C 15.0, 17.5, and 20.0%, w/w), as well as of pH (6.0, 7.0, and 8.0) on the response variables; moreover, partition coefficient (K), yield (Y), and purification factor (PF) were analyzed. The most suitable parameters to purify tannase secreted by A. tamarii URM 7115 through a biphasic system were 600 (g/mol) M, 24% (w/w) C, 15% (w/w) C at pH 6.0 and they resulted in 6.33 enzyme partition, 131.25% yield, 19.80 purification factor and 195.08 selectivity. Tannase secreted by A. tamarii URM 7115 purified through aqueous biphasic systems composed of PEG/citrate can be used for industrial purposes, since it presents suitable purification factor and yield.
本研究的目的是基于二因子设计评估聚乙二醇（PEG）浓度、摩尔质量、pH值和柠檬酸盐浓度对双水相体系的影响，并检验其纯化由黑曲霉URM 7115分泌的单宁酶的能力。单宁酶是在改良的察氏培养基中于26°C通过深层发酵67小时产生的，并添加了酵母提取物和单宁酸。采用析因设计评估PEG摩尔质量（M 600、4000和8000 g/mol）、PEG（C 20.0、22.0和24.0% w/w）和柠檬酸盐浓度（C 15.0、17.5和20.0%，w/w）以及pH值（6.0、7.0和8.0）对响应变量的影响；此外，还分析了分配系数（K）、产率（Y）和纯化因子（PF）。通过双水相体系纯化黑曲霉URM 7115分泌的单宁酶的最合适参数为：M为600（g/mol）、C为24%（w/w）、C为15%（w/w），pH值为6.0，此时酶分配系数为6.33、产率为131.25%、纯化因子为19.80、选择性为195.08。通过由PEG/柠檬酸盐组成的双水相体系纯化的黑曲霉URM 7115分泌的单宁酶可用于工业目的，因为它具有合适的纯化因子和产率。
