木葡糖酸醋杆菌株型对细菌纤维素产量与性能的影响

Effects of Different Gluconacetobacter xylinus Strains on Yield and Properties of Bacterial Cellulose

摘要: 木葡糖酸醋杆菌是重要的细菌纤维素生产菌。该课题以40 g/L葡萄糖为碳源，研究了静态培养时5株菌种对细菌纤维素产量与性能的影响。采用扫描电镜、X射线衍射和万能材料测试机分别对细菌纤维素进行了形貌观察、结晶度表征以及力学性能测试。研究结果表明：细菌纤维素的产量排序依次为DHU-ZCY-1 (3.9 g/L) > DHU-ATCC-1 (2.6 g/L) > DHU-ZGD-1 (2.3 g/L) > DHU-YQ-1 (1.7 g/L) > ATCC23770 (0.6 g/L)；株型对细菌纤维素的含水率和结晶度基本无影响；不同菌株产的细菌纤维素湿膜的断裂拉伸强度大小依次如下：DHU-ZGD-1 (350 KPa) > DHU-ZCY-1 (150 KPa) > DHU-YQ-1 (68 KPa) > DHU-ATCC-1 (56 KPa) > ATCC23770 (35 KPa)；菌株对细菌纤维素的微观结构影响甚微，纤维直径大都分布在65~91 nm之间。

Abstract: Gluconacetobacter xylinus is an important bacterial cellulose (BC) producing bacterium. Effects of five strains of G. xylinus on cellulose production and properties were investigated by using D-glu- cose as carbon source. The initial concentration of glucose was 40 g/L. X-ray diffraction analysis, scanning electron microscopy and universal material testing machine were used to characterize the bacterial cellulose. The volume yield of bacterial cellulose by the five strains of G. xylinus was as follows: DHU-ZCY-1 (3.9 g/L) > DHU-ATCC-1 (2.62 g/L) > DHU-ZGD-1 (2.34 g/L) > DHU-YQ-1 (1.72 g/L) > ATCC23770 (0.61 g/L). The highest volume yield was around 7 times higher than the lowest one. Tensile strength of bacterial cellulose of the five strains was as follows: DHU-ZGD-1 > DHU-ZCY-1 > DHU-YQ-1 > DHU-ATCC-1 > ATCC23770. The results showed that unremarkable morphological difference of bacterial cellulose was found among the five strains. And there was no obvious difference in water content and crystallinity of BC obtained by the five strains. The fiber diameters were in the range between 65 nm and 91 nm.