Jaiboon Kanokjun, Chouwatat Patcharida, Napathorn Suchada Chanprateep
Biotechnology Program, Faculty of Science, Chulalongkorn University, Pathumwan, Bangkok 10330, Thailand.
Bangchak Corporation Public Company Limited, M Tower Building, 8(th) Floor, Sukhumvit Rd, Phra Khanong, Bangkok 10260, Thailand.
Int J Biol Macromol. 2024 Nov;281(Pt 4):136556. doi: 10.1016/j.ijbiomac.2024.136556. Epub 2024 Oct 13.
This study demonstrated that Burkholderia sp. SCN-KJ is a promising novel species for the biovalorization of crude glycerol to polyhydroxybutyrate (PHB) and galactose-rich heteroexopolysaccharide (EPS). Whole-genome and genetic evolution analyses revealed separation of the different clades according to the ANIb and dDDH analyses, which confirmed that Burkholderia sp. SCN-KJ is a novel species. The highest PHB production from crude glycerol was 12.9 ± 0.4 g/L (72.9 ± 2.1 % w/w), with a productivity of 0.46 g/L/h and Y of 0.3 g/g at 28 h in a 10 L fermenter. The galactose-rich hetero-EPS began to be produced after nitrogen depletion, resulting in a concentration of 22.4 ± 0.2 g/L at 38 h. Examination of the carbon-to‑nitrogen ratio (C/N) showed that nitrogen-rich condition (C/N 20) was optimal for PHB production, whereas nitrogen-depleted condition promoted EPS production, showing two different extrema. The findings showed that Burkholderia sp. SCN-KJ has the potential to transform the landscape of biovalorization for sustainable production.
本研究表明，伯克霍尔德氏菌属SCN-KJ是一种很有前景的新物种，可将粗甘油生物转化为聚羟基丁酸酯（PHB）和富含半乳糖的杂多糖（EPS）。全基因组和遗传进化分析显示，根据ANIb和dDDH分析，不同分支相互分离，这证实了伯克霍尔德氏菌属SCN-KJ是一个新物种。在10 L发酵罐中，28 h时，以粗甘油为原料生产PHB的最高产量为12.9±0.4 g/L（72.9±2.1% w/w），生产率为0.46 g/L/h，Y为0.3 g/g。富含半乳糖的杂EPS在氮耗尽后开始产生，38 h时浓度为22.4±0.2 g/L。碳氮比（C/N）检测表明，富氮条件（C/N 20）最适合PHB生产，而贫氮条件促进EPS生产；显示出两个不同的极值。研究结果表明，伯克霍尔德氏菌属SCN-KJ有潜力改变生物转化的格局，实现可持续生产。
