Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands.
Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands.
Water Res. 2017 Dec 1;126:472-480. doi: 10.1016/j.watres.2017.09.031. Epub 2017 Sep 19.
Double-limitation systems have shown to induce polyhydroxyalkanoates (PHA) production in chemostat studies limited in e.g. carbon and phosphate. In this work the impact of double substrate limitation on the enrichment of a PHA producing community was studied in a sequencing batch process. Enrichments at different C/P concentration ratios in the influent were established and the effect on the PHA production capacity and the enrichment community structure was investigated. Experimental results demonstrated that when a double substrate limitation is imposed at a C/P ratio in the influent in a range of 150 (C-mol/mol), the P-content of the biomass and the specific substrate uptake rates decreased. Nonetheless, the PHA storage capacity remained high (with a maximum of 84 wt%). At a C/P ratio of 300, competition in the microbial community is based on phosphate uptake, and the PHA production capacity is lost. Biomass specific substrate uptake rates are a linear function of the cellular P-content, offering advantages for scaling-up the PHA production process due to lower oxygen requirements.
双限制系统已被证明可以在例如碳和磷酸盐限制的恒化器研究中诱导聚羟基烷酸酯 (PHA) 的产生。在这项工作中，在序批式工艺中研究了双底物限制对PHA 产生群落的富集的影响。在入口处建立了不同 C/P 浓度比的富集物，并研究了它们对 PHA 生产能力和富集群落结构的影响。实验结果表明，当在入口处以 C/P 比为 150（C-摩尔/摩尔）施加双底物限制时，生物质的 P 含量和特定底物摄取率降低。尽管如此，PHA 储存能力仍然很高（最高可达 84wt%）。在 C/P 比为 300 时，微生物群落中的竞争基于磷酸盐摄取，PHA 生产能力丧失。生物质的特定底物摄取率是细胞内 P 含量的线性函数，由于对氧气的需求较低，因此为扩大 PHA 生产过程提供了优势。
