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通过非表面活性剂溶胶凝胶法,采用海藻糖和甘油既作为保护剂又作为造孔剂,并使用羟乙基纤维素(HEC)作为添加剂以减轻凝胶过程中的收缩,成功地将酵母原位包埋在具有介孔结构的干胶中,维持了酵母的存活并探索了包埋酵母的代谢动力学与材料孔径参数改良的相关性.选择四乙氧基硅烷(TEOS)和甲基三乙氧基硅烷(MTES)共同作为前驱体,并将湿胶(含水量60%)转变为干胶(含水量10%)以增强材料,部分实现了游离酵母的抑制.通过单轴抗压强度测试说明干胶的单轴压缩强度整体上是湿胶的13倍,最低可达7.13 MPa.由平板计数法算得溶胶中的酵母浓度为1.5×108mL-1,折算成干胶粉末则为6.4×108g-1.通过对材料进行比表面积及孔隙分析和代谢动力学表征,发现了包埋酵母的代谢动力学与材料孔径参数的相关性.通过非表面活性剂法制得的干胶的比表面积可达800 m2g-1,孔体积可达0.44 cm3g-1,孔径可达2.7 nm.在此条件下,采用独立取样的统计方法,对无游离酵母的样品点进行代谢动力学表征,包埋酵母60 h内可以代谢掉发酵液中89%的葡萄糖.
The non-surfactant sol-gel method using trehalose and glycerol both as a protective agent and a pore-forming agent, and using hydroxyethylcellulose (HEC) as an additive to reduce the shrinkage during the gelation, successfully transformed the yeast In situ embedded in a dry glue with a mesoporous structure to maintain the survival of the yeast and explore the correlation between the kinetics of the immobilized yeast and the improvement of the material pore size parameters.Tetraethoxy silane (TEOS) and methyl Triethoxysilane (MTES) together as a precursor, and the wet glue (water content 60%) into dry glue (water content 10%) to enhance the material, in part, to achieve the inhibition of free yeast by uniaxial compression The strength test shows that the uniaxial compressive strength of the adhesive is 13 times as high as that of the wet glue as a whole and the lowest is 7.13 MPa. The yeast concentration in the sol is 1.5 × 108 mL-1 calculated by the tablet counting method and 6.4 × 108g-1. By the surface area of the material and pore analysis and metabolic kinetic characterization, we found that the correlation between the kinetics of the embedded yeast and the material pore size parameters.With the non-surfactant method, the specific surface area Up to 800 m2g-1, pore volume up to 0.44 cm 3g-1, the pore diameter can reach 2.7 nm.Under this condition, the statistical method of independent sampling was used to characterize the metabolites of the samples without free yeast, and the entrapped yeast could metabolize 89% of the fermentation broth within 60 h glucose.