Li Quanfei, Chen Qian, Yang Kai, Hu Kai, Lei Peng, Gu Yi'an, Sun Liang, Xu Hong, Wang Rui
College of Food Science and Light Industry, Nanjing University of Technology, Nanjing 210009, Jiangsu, China.
State Key Laboratory of Materials-oriented Chemical Engineering, Nanjing 210009, Jiangsu, China.
Sheng Wu Gong Cheng Xue Bao. 2024 Mar 25;40(3):921-930. doi: 10.13345/j.cjb.230475.
NX-11 exopolysaccharide (PAPS) is a novel microbial biostimulant that enhances crop resistance to salt and drought stress. It is biodegradable and holds promising applications in improving agricultural yield and efficiency. However, the fermentation process of PAPS exhibits a high viscosity due to low oxygen transfer efficiency, which hinders yield improvement and downstream processing. This study aimed to investigate the effects of seven oxygen carriers (Span 80, Span 20, Tween 80, Tween 20, glycerin, olive oil, and soybean oil) on fermentation yield. The results showed that the addition of 0.5% (/) Tween 20 significantly enhanced the production of PAPS. Moreover, the introduction of 0.5% (/) Tween 20 in a 7.5 L fermenter resulted in a PAPS titer of (16.85±0.50) g/L, which was 17.70% higher than that of the control group. Furthermore, the rheological characterization and the microstructure analysis of the polysaccharide products revealed that the characteristic structure of polysaccharides remained unchanged in the oxygen carrier treated group, but their viscosity increased. These findings may facilitate enhancing the biosynthesis efficiency of other polymer products.
NX - 11胞外多糖（PAPS）是一种新型微生物生物刺激素，可增强作物对盐胁迫和干旱胁迫的抗性。它可生物降解，在提高农业产量和效率方面具有广阔的应用前景。然而，由于氧气传递效率低，PAPS的发酵过程表现出高粘度，这阻碍了产量的提高和下游加工。本研究旨在研究七种氧载体（司盘80、司盘20、吐温80、吐温20、甘油、橄榄油和大豆油）对发酵产量的影响。结果表明，添加0.5%（/）吐温20显著提高了PAPS的产量。此外，在7.5 L发酵罐中引入0.5%（/）吐温20后，PAPS效价达到（16.85±0.50）g/L，比对照组高出17.70%。此外，对多糖产物的流变学表征和微观结构分析表明，氧载体处理组多糖的特征结构保持不变，但其粘度增加。这些发现可能有助于提高其他聚合物产品的生物合成效率。
