Abstract：The effects of some sugars (glucose, mannose, fructose, sucrose and chitosan) and polyols (glycol, glycerol and sorbitol) as protective additive on the thermostability of ?-mannanase were studied. The optimal reaction temperatures of ?-mannanase and the thermodynamics and the deactivation kinetics with or without additives were also investigated. The experimental results show that sucrose, chitosan and sorbitol could apparently improve the thermal stability of ?-mannanase when their concentration was kept at 2 g/L. The optimal combination additive proportion was sucrose: chitosan : sorbitol = 1 : 2 : 2 (molar ratio) using the orthogonal experimental design. The sucrose, chitosan, glycerol, sorbitol and the combination additive might increase the optimal reaction temperature from 50°C to about 60°C due to their good protection effect. The thermal deactivation curves of ?-mannanase accorded with the kinetic rules of first order reaction, and the corresponding kinetic and thermodynamic parameters were calculated. Meanwhile, the protective mechanism of the additives against deactivation of enzyme was also discussed.
出版日期: 2008-12-05
引用本文:
. Enhancing thermostability of -mannanase by protective additives [J]. Frontiers of Chemical Engineering in China, 2008, 2(4): 439-442.
LIU Zhaohui, QI Wei, WU Weina, LIU Yue, HE Zhimin. Enhancing thermostability of -mannanase by protective additives . Front. Chem. Sci. Eng., 2008, 2(4): 439-442.
Whitaker J . Handbook of Food Enzyme. New York: Dekker Press, 2002
2
Sachslehner A, Foidl G, Foidl N, Gübitz G and Haltrich D . Hydrolysis of isolated coffeemannan and coffee extract by mannanases of Sclerotium rolfsii. J Biotechnol, 2000, 80(2): 127–134. doi:10.1016/S0168-1656(00)00253-4
3
Jackson M E, Fodge D W, Hsiao H Y . Effects of β-mannanase in corn-soybean meal diets on laying hen performance. Poult Sci, 1999, 78(12): 1737–1741
4
Zheng P R . Oligosaccharide, functional bifidobacterium and theircorrelation. China Food Additive, 1998, (2): 28–31 (in Chinese)
5
Zhang J, He M X, He Z M . Operational and storage stability ofneutral β-mannanase from Bacillus licheniformis. Biotechnol Lett, 2002, 24(19): 1611–1613. doi:10.1023/A:1020332011421
6
Thierry L, Charles G, Georges F . Psychrophilic enzymes: revisitingthe thermodynamic parameters of activation may explain local flexibility. Biochim Biophys Acta, 2000, 1543(1): 1–10
7
Graber M, Comber D . Effect of polyolson fungal alpha-amylase thermostability. Enzyme Microb Technol, 1989, 11(10): 673–677. doi:10.1016/0141-0229(89)90007-0
8
Back J F, Oakenfull D, Smith M B . Increased thermal stabilityof proteins in the presence of sugars and polyols. Biochemistry, 1979, 18(23): 5191–5196. doi:10.1021/bi00590a025
9
Samborska K, Guiavarc'h Y, Loey A V, Hendrickx M . The thermal stability of Aspergillus oryzae alpha-amylasein presence of sugars and polyols. J FoodProcess Eng, 2006, 29(3): 287–303. doi:10.1111/j.1745-4530.2006.00062.x
10
Anjum F, Rishi V, Ahmad F . Compatibility of osmolytes with Gibbsenergy of stabilization of proteins. BiochimBiophy Acta―Protein Structure and Molecular Enzymology, 2000, 1476(1): 75–84. doi:10.1016/S0167-4838(99)00215-0
11
Gekkot K, Timasheff S N . Mechanism of protein stabilization by glycerol: preferential hydrationin glycerol-water mixtures. Biochemistry, 1981, 20(16): 4667–4676. doi:10.1021/bi00519a023
12
Manning M C, Matsuura J E, Kendrick B S, Meyer J D, Dormish J J, Vrkljan M, Ruth J R, Carpenter J F, Sheftert E . Approaches for increasingthe solution stability of proteins. BiotechBioeng, 1995, 48(5): 506–512. doi:10.1002/bit.260480513
13
Ruan K, Xu C, Li T, Lang R, Balny C . The thermodynamic analysis of proteinstabilization by sucrose and glycerol against pressure-induced unfolding:The typical example of the 33-kDa protein from spinach photosystemII. Eur J Biochem, 2003, 270(8): 1654–1661. doi:10.1046/j.1432-1033.2003.03485.x
