Liu Yan, Liao Wei, Chen Shulin
Department of Biological Systems Engineering and Center for Bioenergy and Bioproducts, Washington State University, L.J. Smith 213, Pullman, Washington 99163, USA.
Biotechnol Bioeng. 2008 Jan 1;99(1):117-28. doi: 10.1002/bit.21531.
Fungal pellet formation is an important topic of fermentation research. It has been reported that many factors such as agitation, medium nutrients, pH, polymer additives, and inoculum size influence the formation of fungal pellets. However, a few studies on the effects of all of these factors on fungal pellet formation have been reported. This paper conducted a comprehensive investigation using a completely randomized design (CRD) on a filamentous fungus, Rhizopus oryzae NRRL 395, in order to discover the effects of the above factors on fungal pellet formation. In addition, other factors, such as addition of biodegradable polymers and spore storage time that have not been reportedly studied were examined and their effects on pellet formation were investigated. A multiple logistic regression model was established to predict the probability of pellet formation using the above factors and their interactions as predictor variables. Model building and diagnostics were obtained using the Statistical Analysis System (SAS 9.0) program. The model developed in this study can be used to predict the pellet formation of other R. oryzae strains as well.
真菌菌球形成是发酵研究的一个重要课题。据报道，许多因素如搅拌、培养基营养成分、pH值、聚合物添加剂和接种量等都会影响真菌菌球的形成。然而，关于所有这些因素对真菌菌球形成影响的研究报道较少。本文采用完全随机设计（CRD）对丝状真菌米根霉NRRL 395进行了全面研究，以发现上述因素对真菌菌球形成的影响。此外，还研究了其他一些尚未见报道的因素，如可生物降解聚合物的添加和孢子储存时间，并探讨了它们对菌球形成的影响。建立了一个多元逻辑回归模型，以上述因素及其相互作用作为预测变量来预测菌球形成的概率。使用统计分析系统（SAS 9.0）程序进行模型构建和诊断。本研究建立的模型也可用于预测其他米根霉菌株的菌球形成情况。
