Using Static Culture Method to Increase the Production of Acetobacter Xylinum Bacterial Cellulose

ABSTRACT

Bacterial cellulose is a natural polymer, usually produced through synthetic (chemically defined) or natural media. However, the current methods of bacterial cellulose production are not ideal because of their low productivity and large number of byproducts. In order to improve the yield of bacterial cellulose, the influence of medium composition, culture time, culture temperature and culture pH on the production of bacterial cellulose by Acetobacter xylinum ATCC 23,767 was studied by single factor method. The optimal medium composition for Acetobacter xylinum can be analyzed by Thermal field emission scanning electron microscopy (TF-SEM) as glucose (20 g/L), yeast extract (5 g/L), peptone (5 g/L), citric acid (2 g/L). Using the logarithmic calculation method, we can determine that the optimal culture conditions are controlled by initial pH of the culture medium of 6 and constant static culture at 28°C for 9 days. Using TF-SEM, Fourier transform infrared (FT-IR) spectroscopy and water contact angle test, the best post-treatment solution can be selected as sodium hydroxide (1%). The results showed that the yield of bacterial cellulose could reach up to 8.5 g/L under the above conditions, and the obtained product exhibited a dense three-dimensional network structure.

摘要

细菌纤维素是一种天然聚合物，通常通过合成（化学定义）或天然介质生产. 然而，目前的细菌纤维素生产方法并不理想，因为它们的生产率低，副产物多. 为了提高细菌纤维素的产量，采用单因素法研究了培养基组成、培养时间、培养温度和培养pH对木醋杆菌ATCC 23,767生产细菌纤维素的影响. 通过热场发射扫描电子显微镜（TF-SEM）可以分析木醋杆菌的最佳培养基组成，如葡萄糖（20 g/L）、酵母提取物（5 g/L）、蛋白胨（5gg/L）、柠檬酸（2 g/L）. 采用对数计算法，可以确定最佳培养条件为: 培养基初始pH为6，28°C恒温培养9d. 通过TF-SEM、傅立叶变换红外光谱（FT-IR）和水接触角测试，可以选择最佳的后处理溶液为氢氧化钠（1%）. 结果表明，在上述条件下，细菌纤维素的产率可达8.5 g/L，所得产物呈现出致密的三维网络结构.

KEYWORDS:

• Bacterial cellulose
• Static cultivation
• fermentation condition
• acetobacter xylinum

关键词:

• 细菌纤维素
• 静态培养
• 发酵条件
• acetobacter xylinum

Acknowledgments

This work was supported by the National Natural Science Foundation of China (22378034, 21908015), Liaoning Province Applied Basic Research Program (2023JH2/101600003), Fujian’s seventh batch of provincial talent introduction “Hundred Talents Plan” team project (202102), Dalian Key Technology R&D Project (2022YF12GX057), and Dalian Science and Technology Innovation Fund Project (2022JJ12SN055).

Disclosure statement

All authors are informed and agree to publish the paper.

Additional information

Funding

The work was supported by the National Natural Science Foundation of China [21908015]; Liaoning Province Applied Basic Research Program [2023JH2/101600003]; Dalian Key Technology R&D Project [2022YF12GX057]; Fujian’s seventh batch of provincial talent introduction ”Hundred Talents Plan” team project [202102]; Dalian Science and Technology Innovation Fund Project [2022JJ12SN055].