Li Mengxing, Wilkins Mark R
Department of Biological Systems Engineering, The University of Nebraska-Lincoln, Lincoln, 68583, NE, USA.
Department of Statistics, The University of Nebraska-Lincoln, Lincoln, 68583, NE, USA.
Bioprocess Biosyst Eng. 2021 Jan;44(1):185-193. doi: 10.1007/s00449-020-02434-1. Epub 2020 Sep 7.
Polyhydroxybutyrate (PHB) is a biodegradable bioplastic that is comparable with many petroleum-based plastics in terms of mechanical properties and is highly biocompatible. Lignocellulosic biomass conversion into PHB can increase profit and add sustainability. Glucose, xylose and arabinose are the main monomer sugars derived from upstream lignocellulosic biomass processing. The sugar mixture ratios may vary greatly depending on the pretreatment and enzymatic hydrolysis conditions. Paraburkholderia sacchari DSM 17165 is a bacterium strain that can convert all three sugars into PHB. In this study, fed-batch mode was applied to produce PHB on three sugar mixtures (glucose:xylose:arabinose = 4:2:1, 2:2:1, 1:2:1). The highest PHB concentration produced was 67 g/L for 4:2:1 mixture at 41 h corresponding to an accumulation of 77% of cell dry weight as PHB. Corresponding sugar conversion efficiency and productivity were 0.33 g PHB/g sugar consumed and 1.6 g/L/h, respectively. The results provide references for process control to maximize PHB production from real sugar streams derived from corn fibre.
聚羟基丁酸酯（PHB）是一种可生物降解的生物塑料，在机械性能方面可与许多石油基塑料相媲美，并且具有高度的生物相容性。将木质纤维素生物质转化为PHB可以增加利润并提高可持续性。葡萄糖、木糖和阿拉伯糖是上游木质纤维素生物质加工产生的主要单糖。糖的混合比例可能会因预处理和酶水解条件的不同而有很大差异。糖假伯克霍尔德氏菌DSM 17165是一种能将所有三种糖转化为PHB的菌株。在本研究中，采用分批补料模式在三种糖混合物（葡萄糖:木糖:阿拉伯糖 = 4:2:1、2:2:1、1:2:1）上生产PHB。对于4:2:1的混合物，在41小时时产生的最高PHB浓度为67 g/L，相当于细胞干重的77%以PHB的形式积累。相应的糖转化效率和生产率分别为0.33 g PHB/消耗的g糖和1.6 g/L/h。这些结果为从玉米纤维衍生的实际糖流中最大化生产PHB的过程控制提供了参考。
