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Pillared clay (Pillared Interlayered Clay, PILC) is a porous solid material, due to its large specific surface area, pore size and acid regulation has been widely applied in the field of catalysis. Montmorillonite is the main material used for the preparation of pillared clay, bentonite is montmorillonite clay ore, Xinjiang Xiazijie area is one of the the bentonite the world's most resource-rich areas and prospective reserves of 50 million tons. However, bentonite because of different origin, composition varies greatly, this paper attempts pillared clays prepared to the Xinjiang Xiazijie bentonite material, the use of immobilized beta-D-glucose glucuronide enzyme assay. The pillared clay bentonite prepared by the different nature of the immobilized enzyme activity, and preferably a pillared clay fixed beta-D-glucuronidase enzyme and its transformation glycyrrhizic acid to generate single-glucuronyl The glycyrrhetinic the acid (GAMG), the following main conclusions: (1) by X-ray diffraction (XRD), N 2 adsorption - desorption, Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM), a carrier is preferably characterized and found: the pillared clay specific surface area of ??the original soil the 57.99 m 2 / g to improve to 177.0 m 2 / g, BJH desorption pore volume of 0.059 mL / g is increased to 0.25 mL / g, is a good enzyme-immobilized carrier, the enzyme fixed thereto by the biasing force of the hydrogen bond. 2 Discussion of the amount of enzyme, the pH of the buffer, temperature, and immobilization time of the immobilized beta-D-glucose uronic acid glycosides activity, fixed rate, the results showed that: the best the immobilized reaction conditions to give the amount of enzyme 2700 U / g of carrier, pH = 3.6, temperature 40 ° C, the the immobilized reaction time 60 min, immobilized beta-D-glucuronic acid glycoside obtained under this condition maximum enzyme activity of up to 1790 U / g carrier , immobilization under mild conditions, fixed rate. 3 licorice acid as substrate to study the nature of the immobilized enzyme, catalytic properties, and comparison with the free enzyme, the results show that: the immobilized enzyme optimum catalytic conditions of pH 6.0, temperature 60 ° C, the reaction kinetics exhibit constant the K m 1.35 mmol · L -1 , glycyrrhizic acid concentration as 2 g / L, the amount of the immobilized enzyme added 20 U / mL substrate Maximum catalytic activity. Compared with the free enzyme, the offset the immobilized enzyme catalytic synthesis GAMG of the optimum pH to the alkaline direction, optimum catalytic temperature increase of 10 ° C, but decreased affinity for the substrate; enzyme by immobilized catalytic specificity has not changed, the storage stability has improved greatly, with certain operational stability. In this paper, based on research Xinjiang Xiazijie region different nature bentonite preparation layer column clay of the development of the use of its fixed-beta-D-glucose aldehyde acid glycosides enzyme and study of its catalytic properties, Xinjiang advantage of mineral resources bentonite the deep processing provides the important the application of ways and the underlying data.
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