当前位置: X-MOL 学术Biotechnol. Biofuels › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Enhanced rhamnolipids production using a novel bioreactor system based on integrated foam-control and repeated fed-batch fermentation strategy.
Biotechnology for Biofuels ( IF 6.3 ) Pub Date : 2020-04-24 , DOI: 10.1186/s13068-020-01716-w
Ning Xu 1, 2 , Shixun Liu 1 , Lijie Xu 1 , Jie Zhou 1 , Fengxue Xin 1 , Wenming Zhang 1 , Xiujuan Qian 1 , Min Li 1 , Weiliang Dong 1, 3 , Min Jiang 1, 3
Affiliation  

Background Rhamnolipids are the best known microbial-derived biosurfactants, which has attracted great interest as potential ''green" alternative for synthetic surfactants. However, rhamnolipids are the major contributors to severe foam problems, which greatly inhibit the economics of industrial-scale production. In this study, a novel foam-control system was established for ex situ dealing with the massive overflowing foam. Based on the designed facility, foam reduction efficiency, rhamnolipids production by batch and repeated fed-batch fermentation were comprehensively investigated. Results An ex situ foam-control system was developed to control the massive overflowing foam and improve rhamnolipids production. It was found that the size of individual bubble in the early stage was much larger than that of late fermentation stage. The foam liquefaction efficiency decreased from 54.37% at the beginning to only 9.23% at the end of the fermentation. This difference of bubble stability directly resulted in higher foam reduction efficiency of 67.46% in the early stage, whereas the small uniform bubbles can only be reduced by 57.53% at the later fermentation stage. Moreover, reduction of secondary foam is very important for foam controlling. Two improved designs of the device in this study obtained about 20% improvement of foam reduction efficiency, respectively. The batch fermentation result showed that the average volume of the overflowing foam was reduced from 58-640 to 19-216 mL/min during the fermentation process, presenting a notable reduction efficiency ranging from 51.92 to 73.47%. Meanwhile, rhamnolipids production of batch fermentation reached 45.63 g/L, and the yield 0.76 g/g was significantly better than ever reported. Further, a repeated fed-batch fermentation based on the overall optimization was carried out. Total rhamnolipids concentration reached 48.67 g/L with the yield around of 0.67-0.83 g/g, which presented an improvement of 62% and 49% compared with conventional batch fermentation by using various kinds of defoamers, respectively. Conclusions The ex situ foam-control system presented a notable reduction efficiency, which helped greatly to easily solve the severe foaming problem without any defoamer addition. Moreover, rhamnolipids production and yield by repeated fed-batch fermentation obtained prominent improvement compared to conventional batch cultivation, which can further facilitate economical rhamnolipids production at large scales.

中文翻译:

使用基于集成泡沫控制和重复补料分批发酵策略的新型生物反应器系统提高鼠李糖脂的生产。

泡沫液化效率从发酵开始时的54.37%下降到发酵结束时的9.23%。这种气泡稳定性的差异直接导致前期的消泡效率更高,达到67.46%,而在发酵后期,均匀的小气泡只能减少57.53%。此外,减少二次泡沫对于泡沫控制非常重要。本研究中装置的两种改进设计分别使消泡效率提高了约 20%。分批发酵结果表明,发酵过程中溢出泡沫的平均体积从58-640减少到19-216 mL/min,减少效率显着,从51.92%到73.47%不等。同时,分批发酵的鼠李糖脂产量达到45.63 g/L,并且产量 0.76 g/g 比以往报道的要好得多。此外,在整体优化的基础上进行了重复的补料分批发酵。总鼠李糖脂浓度达到48.67 g/L,产率在0.67-0.83 g/g左右,与使用各种消泡剂的常规分批发酵相比,分别提高了62%和49%。结论非原位控泡体系具有显着的减泡效果,有助于在不添加任何消泡剂的情况下轻松解决严重的起泡问题。此外,与常规分批培养相比,重复补料分批发酵的鼠李糖脂产量和产量均获得显着提高,可进一步促进鼠李糖脂的大规模经济生产。76 g/g 比以往报道的要好得多。此外,在整体优化的基础上进行了重复的补料分批发酵。总鼠李糖脂浓度达到48.67 g/L,产率在0.67-0.83 g/g左右,与使用各种消泡剂的常规分批发酵相比,分别提高了62%和49%。结论非原位控泡体系具有显着的减泡效果,有助于在不添加任何消泡剂的情况下轻松解决严重的起泡问题。此外,与常规分批培养相比,重复补料分批发酵的鼠李糖脂产量和产量均获得显着提高,可进一步促进鼠李糖脂的大规模经济生产。76 g/g 比以往报道的要好得多。此外,在整体优化的基础上进行了重复的补料分批发酵。总鼠李糖脂浓度达到48.67 g/L,产率在0.67-0.83 g/g左右,与使用各种消泡剂的常规分批发酵相比,分别提高了62%和49%。结论非原位控泡体系具有显着的减泡效果,有助于在不添加任何消泡剂的情况下轻松解决严重的起泡问题。此外,与常规分批培养相比,重复补料分批发酵的鼠李糖脂产量和产量均获得显着提高,可进一步促进鼠李糖脂的大规模经济生产。进行了基于整体优化的重复补料分批发酵。总鼠李糖脂浓度达到48.67 g/L,产率在0.67-0.83 g/g左右,与使用各种消泡剂的常规分批发酵相比,分别提高了62%和49%。结论非原位控泡体系具有显着的减泡效果,有助于在不添加任何消泡剂的情况下轻松解决严重的起泡问题。此外,与常规分批培养相比,重复补料分批发酵的鼠李糖脂产量和产量均获得显着提高,可进一步促进鼠李糖脂的大规模经济生产。进行了基于整体优化的重复补料分批发酵。总鼠李糖脂浓度达到48.67 g/L,产率在0.67-0.83 g/g左右,与使用各种消泡剂的常规分批发酵相比,分别提高了62%和49%。结论非原位控泡体系具有显着的减泡效果,有助于在不添加任何消泡剂的情况下轻松解决严重的起泡问题。此外,与常规分批培养相比,重复补料分批发酵的鼠李糖脂产量和产量均获得显着提高,可进一步促进鼠李糖脂的大规模经济生产。83 g/g,与使用各种消泡剂的常规分批发酵相比,分别提高了62%和49%。结论非原位控泡体系具有显着的减泡效果,有助于在不添加任何消泡剂的情况下轻松解决严重的起泡问题。此外,与常规分批培养相比,重复补料分批发酵的鼠李糖脂产量和产量均获得显着提高,可进一步促进鼠李糖脂的大规模经济生产。83 g/g,与使用各种消泡剂的常规分批发酵相比,分别提高了62%和49%。结论非原位控泡体系具有显着的减泡效果,有助于在不添加任何消泡剂的情况下轻松解决严重的起泡问题。此外,与常规分批培养相比,重复补料分批发酵的鼠李糖脂产量和产量均获得显着提高,可进一步促进鼠李糖脂的大规模经济生产。在不添加任何消泡剂的情况下,极大地帮助轻松解决了严重的起泡问题。此外,与常规分批培养相比,重复补料分批发酵的鼠李糖脂产量和产量均获得显着提高,可进一步促进鼠李糖脂的大规模经济生产。在不添加任何消泡剂的情况下,极大地帮助轻松解决了严重的起泡问题。此外,与常规分批培养相比,重复补料分批发酵的鼠李糖脂产量和产量均获得显着提高,可进一步促进鼠李糖脂的大规模经济生产。
更新日期:2020-04-24
down
wechat
bug