Pichia pastoris fermentation for phytase production using crude glycerol from biodiesel production as the sole carbon source
Pichia pastoris fermentation for phytase production using crude glycerol from biodiesel production as the sole carbon source
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DOI：
10.1016/j.bej.2008.09.020
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发表时间：
2009-02-15
影响因子：
3.9
通讯作者：
Zhang, Zisheng
中科院分区：
文献类型：
--
作者：
Tang, Shuiquan;Boehme, Lindsay;Zhang, Zisheng
粗甘油是生物柴油生产过程中的副产物，其有效利用具有显著的经济效益和环境效益。本研究以低品位甘油为唯一碳源，利用pGAP组成型表达载体构建重组毕赤酵母，并在此基础上进行植酸酶的发酵研究。在分批和补料分批模式下，使用分析甘油和生物柴油甘油在分批和补料分批发酵中研究了重要培养条件的影响。分析了以下因素：初始甘油浓度，溶解氧水平，以及补料策略对细胞生长生物量和蛋白质产量的影响。在分批发酵中，当粗甘油浓度高达70 g/L时，细胞生长受到明显抑制。然而，通过以较低的粗甘油水平开始培养，在补料分批模式下克服了这种抑制作用。最后，以粗生物柴油甘油为唯一碳源进行分批补料发酵，获得了高达146 g（细胞干重）/L发酵液和1125 U/mL上清液的细胞密度和植酸酶活性水平。该研究证明了利用生物柴油生产中的粗甘油作为碳源在重组毕赤酵母的高细胞密度发酵中工业规模大规模生产植酸酶的潜力。(C)2008 Elsevier B. V.保留所有权利。
Efficient utilization of crude glycerol, a by-product from biodiesel production, could bring significant economic and environmental benefits. in this work, a low-grade glycerol was used as the sole carbon source in phytase production with recombinant Pichia pastoris possessing a pGAP-based constitutive expression vector. In batch and fed-batch modes, the effects of important cultivation conditions were investigated using both analytical and biodiesel glycerols in batch and fed-batch fermentations. The following factors were analyzed: initial glycerol concentration, dissolved oxygen level, and the effect of feeding strategy on cell growth biomass and protein production. Significant cell growth inhibition was observed in batch fermentation when the initial crude glycerol concentration was as high as 70g/L. However, such inhibition was overcome in fed-batch mode by starting the cultivation with a lower crude glycerol level. Finally, cell densities and phytase activity levels of as high as 146 g (dry cell weight)/L broth and 1125 U/mL supernatant were achieved in the fed-batch fermentation with crude biodiesel glycerol as the sole carbon source. The study has proven the potential of using crude glycerol from biodiesel production as the carbon source for industrial scale phytase mass production in high cell density fermentations with recombinant P. pastoris. (C) 2008 Elsevier B.V. All rights reserved.