Abstract：
This study aimed to enhance the extracellular polymeric substances (EPS) production of Virgibacillus dokdonensis VITP14 and explore its antioxidant potential. EPS and biomass production by VITP14 strain were studied under different culture parameters and media compositions using one factor at a time method. Among different nutrient sources, glucose and peptone were identified as suitable carbon and nitrogen sources. Furthermore, the maximum EPS production was observed at 5% of inoculum size, 5 g/L of NaCl, and 96 h of fermentation. Response surface methodology was employed to augment EPS production and investigate the optimal levels of nutrient sources with their interaction. The strain was observed to produce actual maximum EPS of about 26.4 g/L for finalized optimum medium containing glucose 20 g/L, peptone 10 g/L, and NaCl 50 g/L while the predicted maximum EPS was 26.5 g/L. There was a nine fold increase in EPS production after optimization study. Additionally, EPS has exhibited significant scavenging, reducing, and chelating potential (>85%) at their higher concentration. This study imparts valuable insights into optimizing moderately halophilic bacterial EPS production and evaluating its natural antioxidant properties. According to findings, V. dokdonensis VITP14 was a promising isolate that will provide significant benefits to biopolymer producing industries.
摘要：
本研究旨在提高多克多杆菌属VITP14的胞外聚合物（EPS）产量，并探索其抗氧化潜力。在不同的培养参数和培养基组成下，使用一次因子法研究了VITP14菌株的EPS和生物量产量。在不同的营养来源中，葡萄糖和蛋白胨被确定为合适的碳源和氮源。此外，最大的EPS产量在接种量的5%时观察到，5g/L的NaCl，和96小时的发酵。采用响应面法来增加EPS的产量，并研究营养源的最佳水平及其相互作用。对于含有葡萄糖20g/L的最终最佳培养基，观察到该菌株产生约26.4g/L的实际最大EPS，蛋白胨10g/L，和NaCl50g/L，而预测的最大EPS为26.5g/L。优化研究后，EPS产量增加了9倍。此外,EPS表现出显著的清除作用，减少,和螯合电位（>85％）在其较高的浓度。这项研究为优化中度嗜盐细菌EPS的生产和评估其天然抗氧化性能提供了有价值的见解。根据调查结果,V.dokdonensisVITP14是一种有前途的分离株，将为生物聚合物生产行业提供重大利益。
