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纤维凝胶固定化增殖酵母连续生产酒精的研究 总被引:2,自引:0,他引:2
本文比较了纤维胶固定增殖酵母与海藻酸钙凝胶球、纤维海藻酸铝凝胶与纤维海藻酸钙凝胶、以及不同厚度的纤维凝胶固定化增殖酵母的发酵结果。重点进行了纤维凝胶固定化增殖酵母连续生产酒精试验。采用1.1L柱式生物反应器,CO2排出通畅,停留时间为4小时,成熟醪中酒精含量为10.1-11.0%(V/V),平均为10.55%,酒精生产能力为9.4g/L.h,总糖利用率为94.5%。 相似文献
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《生物加工过程》2016,(4)
本文旨在开发抗冻酵母AFY-1的海藻酸钙凝胶固定化技术,探明固定化机制。在不同海藻酸钠浓度、Ca Cl2浓度和固化时间条件下制备固定化酵母,并在一定条件下进行乙醇发酵,分析发酵能力与酵母生长、凝胶颗粒通透性之间的关系,然后通过响应面实验优化固定化条件。实验结果显示,乙醇收率随凝胶颗粒通透性的增加呈线性增加,而酵母生长与固定化条件无关,基本保持不变。当固定化条件为海藻酸钠质量分数1.45%、Ca Cl2质量分数17.45%、固化时间1.09 h时,固定化酵母的乙醇收率可达24.1%,高于游离酵母的20.9%。此外,固定化酵母的生长能力明显强于游离酵母。在固定化酵母的乙醇发酵中,每个三角瓶(250 m L)内的总细胞数从5.0×10~8个增加到大约11.2×10~8个;而在游离酵母的乙醇发酵中,每个三角瓶内的总细胞数从5.0×10~8个仅增加到7.5×10~8个。 相似文献
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柠檬酸是利用微生物代谢生产的一种极为重要的有机酸.广泛应用于食品、饮料、化工、冶金、印染等各个领域。在国外,近10年来,利用固定化细胞生产柠檬酸已获得较广泛的研究〔1-6〕,国内也有学者指出,柠檬酸发酵的趋向是利用固定化细胞进行连续化生产⑺。而国内这方面的研究报道很少〔8,9〕。我们利用海藻酸钙凝胶包埋固定化黑曲霉细胞生产柠檬酸.探讨了碳源种类及其浓度对固定化细胞生产柠檬酸的影响。现将结果报道如下。 相似文献
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固定化微环境对酿酒酵母代谢的影响 总被引:3,自引:1,他引:3
本文报道不同载体固定化酵母的某些代谢行为和细胞形态。观察到以海藻酸钙凝胶固定酵母,其发酵液总挥发酸量、乙酸量分别比自然细胞减少25.8%和50.O%,而丁二酸量高出自然细胞36.5%。以海藻酸钙,聚乙烯醇凝胶固定酵母,其氨基氮的利用率比自然细胞分别提高31.1%和34.1%,在固定化前后、酵母菌对各种a-氨基酸的利用速度亦都发生明显的变化。电镜观察,酿酒酵母的细胞膜内陷、形成“凹池”。 相似文献
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罗明典 《中国生物工程杂志》1987,7(1):33-36
固定化细胞技术是生物工程技术的一个重要方面,该技术一般有几种方法即包埋法、交联法和载体结合法(如共价结合、离子结合、物理吸附),国内科研工作者已用国产卡拉胶制备固定化细胞生产葡萄糖、L-丙氨酸等多种产品,上海工业微生物研究所用海藻酸钙凝胶包埋酵母细胞快速发酵生产啤酒的实验成功。 相似文献
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采用PVA为载体共固定化酿酒酵母和产香酵母发酵海藻,酿造海藻酒。对游离细胞与固定化细胞的分批发酵和连续发酵的动力学进行了研究并建立了相应的发酵动力学方程。实验结果表明:酿酒酵母和产香酵母二种菌种菌量的最佳配比为4:l,发酵温度20℃.共固定化细胞分批发酵和连续发酵凝胶粒的充填系数分别为0.25和0.5,游离混合细胞的发酵时间为7d。共固定化细胞连续发酵稀释速率0.12/h,其发酵时间为0.5d左右。经160d连续发酵实验,PVA固定化细胞粒子的机械强度良好。 相似文献
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利用克隆获得的具有双重辅酶依赖性的热带假丝酵母xyl1基因,通过表达载体pGAPZB转入巴斯德毕赤酵母X-33,采用海藻酸钙凝胶包埋法固定该重组菌,研究固定化条件下玉米芯水解液的发酵特性,实现对玉米芯等农业废弃物资源的利用。结果表明,转化xyl1基因的巴斯德毕赤酵母X-33的总酶活达到1.64U/mg。固定化细胞的最适发酵条件为pH 6.0、30℃、接种量20%、装液量28%、转速130r/min,木糖醇转化率为37.5%。为生物转化法大规模生产木糖醇以及乙醇提供新的选择途径。 相似文献
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Summary Enhanced rates of ethanol production byPachysolen tannophilus from D-xylose were obtained by performing the fermentation with recycled cells in suspension culture or immobilized in a Ca-alginate gel. Fermentation under these conditions did not require aeration. Increasing temperature from 30 to 37°C enhanced the amount of ethanol produced in 24 hours from the recycled or the immobilized cells.Issued as National Research Council of Canada Publication Number 19475. 相似文献
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G Zayed 《Journal of industrial microbiology & biotechnology》1997,19(1):39-42
Among three esters of p-hydroxybenzoate, n-butyl p-hydroxybenzoate was selected as the best antimicrobial substance. Molasses medium sterilized by this ester was used as
a substrate for ethanol production. n-Butyl p-hydroxybenzoate (0.15% w/v) completely inhibited the growth of free yeast cell inoculum, Ca-alginate immobilized yeast
inoculum and bacterial contaminants. Immobilization of the yeast cell inoculum in Ca-alginate with castor oil (6% v/v) offered
a yeast cell protection against the inhibitory effect of n-butyl p-hydroxybenzoate. The presence of castor oil in this immobilization system did not affect the metabolic activity of the yeast
in beads compared to the cells immobilized without castor oil. The yeast cell beads in this system completely utilized up
to 25% molasses sugar with an ethanol yield of 10.58%, equal to 83% of its theoretical value. The beads were stable and
could be used successfully for seven cycles of batch fermentation. The optimum fermentation temperature using this system
was 35°C.
Received 21 January 1997/ Accepted in revised form 05 May 1997 相似文献
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M. Decleire N. van Huynh J. C. Motte W. De Cat 《Applied microbiology and biotechnology》1985,22(6):438-441
Summary Whey hydrolysis was compared in column reactors containing whole yeast cells immobilized in Ca-alginate or in hen egg white in relation to cell -galactosidase activity, flow rates, temperature and time. With cells of 1.3 U/mg dry weight (ONPG method) immobilized in Ca-alginate, 80% hydrolysis was obtained at 4° and 20° C with, respectively 0.50 and 1.65 bed volume/H; the values were 0.2 and 0.74 with cells entrapped in hen egg white. When the flow rate was expressed as ml/H/g wet yeast, no significant difference was observed between both matrices and 80% hydrolysis was reached with a flow rate 1.7 and 5 according to the temperature. The best performance was achieved by the yeast egg white reactor. At 4°C, hydrolysis decreased by 10% after 13 days; by 20% after 17 days. The presence of lactose transport inhibitors in whey did not significantly influence lactose hydrolysis.M. Decleire et al.: Hydrolysis of whey by immobilized whole cells of Kluyveromyces bulgaricus 相似文献
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Biosorption of 2,4-dichlorophenol by immobilized white-rot fungus Phanerochaete chrysosporium from aqueous solutions 总被引:1,自引:0,他引:1
The fungus Phanerochaete chrysosporium was immobilized in several polymer matrices: Ca-alginate, Ca-alginate-polyvinyl alcohol (PVA) and pectin, and was then used as a biosorbent for removing 2,4-dichlorophenol (2,4-DCP) in wastewater. Immobilization of P. chrysosporium onto pectin was less efficient than that onto other matrices because of its poor mechanical strength and low adsorption efficiency. Ca-alginate immobilized fungal beads with biocompatibility exhibited good mechanical strength and adsorption efficiency over 60%. Among the different biomass dosages in Ca-alginate immobilized fungal beads, 1.25% (w/v) was the optimum. The adsorption data of 2,4-DCP on the blank Ca-alginate beads, free, and immobilized fungal biomass could be described by the Langmuir and Freundlich isotherms very well. Desorption operation was efficiently completed by using distilled water as eluant, and the desorption efficiency reached 82.16% at an optimum solid/liquid ratio of 14.3. The consecutive adsorption/desorption cycles studies employing the Ca-alginate immobilized fungal beads demonstrated that the immobilized fungal biomass could be reused in five cycles without significant loss of adsorption efficiency and adsorbent weight. 相似文献
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Summary Baker's yeast cells (40% w/v) were immobilized in 2% Ca-alginate and were used in a batch process for the removal of glucose from egg melange by fermentation. Immobilized cells (10 g) could completely remove the glucose from 135 ml melange in 60 min. The immobilized preparation was repeatedly used in 30 batches without decrease in the activity. 相似文献
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A new immobilized cell system providing protection against toxic solvents was investigated so that normal fermentations could be carried out in a medium containing toxic solvents. The system consists of immobilized growing cells in Ca-alginate gel beads to which vegetable oils, which are inexpensive absorbents of solvents, had been added. The ethanol fermentation of Saccharomyces cerevisiae ATCC 26603 was used as a model fermentation to study the protection afforded by the system against solvent toxicities. The fermentation was inhibited by solvents such as 2-octanol, benzene, toluene, and phenol. Ethanol production of one batch was not finished even after 35 h using immobilized growing yeast cells in conventional Ca-alginate gel beads in an ethanol production medium (5% glucose) containing 0.1% 2-octanol, which is used as a solvent for liquid-liquid extraction and is one of the most toxic solvents in our experiments. With the new immobilized growing cell system using vegetable oils, however, four repeated batch fermentations were completed in 35 h. Castor oil provided even more protection than soy bean, olive, and tung oils, and it was possible to complete six repeated batches in 35 h. The immobilized cell system with vegetable oils also provided protection against other toxic solvents such as benzene and toluene. A possible mechanism for the protective function of the new immobilized cell system is discussed. 相似文献
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A. M. Nolan N. Barron D. Brady T. McAree D. Smith L. McHale A. P. McHale 《Biotechnology letters》1994,16(8):849-852
Summary In comparing ethanol production by free and Ca-alginate immobilized cultures of the thermotolerant yeast, Kluyveromyces marxianus IMB3, on glucose-containing media at 45°C, it was found that initial yields produced by the immobilized culture lagged behind those produced by cultures in free suspension. However, in subsequent batch-feed experiments it was demonstrated that the ethanol-producing ability of the immobilized preparation increased with successive feeds, while production by the free suspension reduced significantly. 相似文献
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Microenvironmentally restricted yeast cell growth within Ca-alginate beads with and without entrapped gas bubbles was considered based on experimental data. Cell growth dynamics was described by (1) the dimensionless cell number density as a function of the cell growth time and (2) the cell distribution per bead cross sections. One of the key control parameters for bioprocess optimization is the matrix resistance stress generated during immobilized cell expansion. The dynamics of the increase in matrix stress was described theoretically based on a multi-scale mathematical model. In order to estimate and reduce the accumulation of matrix stress we considered repeated stress relaxation cycles in separate rheological experiments without immobilized cells.The results revealed that the increase in resistance stress within the Ca-alginate matrix was significant (∼7 kPa) after 10 repeated cycles, even under a low compression strain of 2% per cycle. The stress could be reduced by using the Ca-alginate matrix with entrapped gas bubbles. The final cell concentration within the beads with entrapped bubbles was 3.3 times higher in comparison with the beads without bubbles. The bubbles could locally amortize the compression effects within the surrounding cell clusters. 相似文献
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Summary The incorporation of small glass hollow spheres into Ca-alginate beads allows the density of immobilized cell preparations to be decreased. For immobilized yeast, glass hollow spheres at 14% (v/v) decrease the density from 1088 to 996 kg m-3, thus greatly changing their hydrodynamic properties. As a consequence, the operation of a three-phase fluidized bed reactor is clearly improved. 相似文献