纤维素酶在不同长度纤维上的吸附行为

Adsorption Behaviors of Cellulase on Cellulose Fiber Fractions with Different Fiber Length

纤维素酶在纤维表面上的吸附是纤维素水解糖化的第一步,探讨了纤维素酶在不同长度纤维上的吸附行为。纤维素酶在纤维上吸附约60 m in后可达到平衡,且吸附量随初始酶用量的增加而增多。吸附过程遵循Langmu ir等温吸附,且纤维素酶在短纤维上具有最大的吸附量,但在长纤维上具有最大的Langmu ir吸附平衡常数,说明纤维素酶在长纤维上能更快地达到吸附平衡。对吸附热力学常数的计算表明,纤维素酶吸附是自发、放热过程,且不可逆吸附。纤维素酶在48目纤维上有最大的吸附焓变,在28目纤维上有最大的吸附熵变。

Adsorption of cellulase on the surfaces of cellulose fibers is the first step of cellulose enzymatic hydrolysis and saccharification.The adsorption behaviors of cellulase on cellulose fiber fractions with different fiber length were quantitatively discussed in this study.The adsorption equilibrium was reached in around 60 minutes,and the adsorption amount increased with increasing initial cellulase dose.The adsorption process was well described by Langmuir isotherm.The maximum adsorption amount was found on the short fiber,and there was the maximum Langmuir adsorption equilibrium constant in the adsorption on the long fiber,which indicated that cellulase shows the highest adsorption affinity on the long fiber.The calculated thermodynamics parameters indicated that adsorption of cellulase on cellulose fiber is a spontaneous,exothermic and irreversible process.The highest enthalpy change ΔH° and entropy change ΔS° were found in the adsorption on 48 mesh fraction and 28 mesh fraction respectively.