Abstract

Providing additives into the culture media is a traditional method to manufacture bacterial cellulose (BC) based nanocomposites. This study employed a novel fermentation process, which is to co-culture Gluconacetobacter hansenii (G. hansenii) with genetically modified Lactococcus lactis (L. lactis) under static conditions, to synthesize BC/HA (hyaluronic acid) nanocomposites. The HA concentration produced by L. lactis and the dry weight of BC/HA during co-culture were regulated by the initial pH values of culture media. The incorporation of HA into the cellulose network increased the crystal sizes when the initial pH values were at 7.0, 6.2, and 5.5. The strain at break was also increased while Young’s modulus was decreased when comparing BC/HA to pure BC produced under the initial pH values of culture media at 7.0 and 6.2. When the initial pH value was 4.0, the HA concentration in the culture media exhibited the lowest level observed, which was 20.4 ± 2.3 mg/L. The BC/HA composite synthesized under this condition exhibited an improved Young’s modulus of 5029 ± 1743 MPa from 2705 ± 656 MPa associated with the pure BC. The FESEM images showed that the presence of HA dramatically changed the distribution of ribbon width in BC/HA compared to that of pure BC. The BC/HA produced by co-culture fermentation didn’t need to add extra and expensive HA during production and could be used in biomedical applications such as wound dressing and tissue engineering.

中文翻译：

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在发酵培养基的不同初始pH值下，通过共同培养汉逊氏杆菌和乳酸乳球菌来生产细菌纤维素/透明质酸纳米复合材料

抽象的

向培养基中提供添加剂是制造基于细菌纤维素（BC）的纳米复合材料的传统方法。本研究中所采用的新颖发酵方法，这是共培养葡逊（G.逊）与转基因的乳酸乳球菌（乳球菌）在静态条件下，以合成BC / HA（透明质酸）纳米复合材料。乳酸乳球菌产生的HA浓度共培养过程中BC / HA的干重受培养基初始pH值的调节。当初始pH值分别为7.0、6.2和5.5时，将HA掺入纤维素网络中会增加晶体尺寸。当将BC / HA与在7.0和6.2的培养基初始pH值下产生的纯BC进行比较时，断裂应变也增加，而杨氏模量降低。当初始pH值为4.0时，培养基中的HA浓度最低，为20.4±2.3 mg / L。在此条件下合成的BC / HA复合材料与纯BC相比具有2705±656 MPa的改进的杨氏模量，为5029±1743 MPa。FESEM图像显示，与纯BC相比，HA的存在极大地改变了BC / HA中碳带宽度的分布。