细菌纤维素合成菌的筛选、鉴定及其产物结构和性质表征

Screening and identification of cellulose-synthesis bacterium and its product structure and property characterization

该研究从腐败葡萄中筛选、分离细菌纤维素(BC)合成菌株,对其进行分子生物学鉴定,并对其产物的结构与性质进行表征。结果表明,筛选分离得到一株细菌纤维素合成菌株,该菌株的16S rRNA基因测序结果表明其属于醋酸菌属(Acetobacter sp.),编号为ZX C6-15。扫描电镜(SEM)和傅立叶变换红外光谱(FT-IR)分析结果表明,菌株ZX C6-15产膜具有典型的3D纳米纤维状结构且具有典型细菌纤维素吸收峰。凝胶渗透色谱(GPC)、X-射线衍射(XRD)分析结果表明,菌株产膜重均分子质量(Mw)为14.1×10^(4)k Da,数均分子质量(Mn)为32.3×10^(4)k Da,分散度为2.28,结晶度指数为96%,吸水率达298%。该菌株合成细菌纤维素具有优良的材料性质,为后续培养条件优化及规模生产奠定基础。

In this study,a bacterial cellulose synthetic strain was screened and isolated from spoilage grape.Molecular biological identification was conducted,and the structure and properties of the products were characterized.The results showed that a bacterial cellulose synthetic strain was screened and isolated,and the 16S rRNA gene sequencing results of the strain indicated that it belonged to Acetobacter sp.,and the serial number was ZX C6-15.The results of scanning electron microscopy(SEM)and Fourier transform infrared spectroscopy(FT-IR)analysis showed that the membrane produced by strain ZX C6-15 had typical 3D nanofiber structure and typical bacterial cellulose absorption peak.Gel permeation chromatography(GPC)and X-ray diffraction(XRD)analysis results showed that the weight of average molecular mass(Mw)of membrane produced by the strain was 14.1×10^(4)kDa,the number of average molecular mass(Mn)was 32.3×10^(4) kDa,the dispersion was 2.28,the crystallinity index was 96%,and the water absorption rate was 298%.The bacterial cellulose synthesized by the strain had excellent material properties,which laid a foundation for the optimization of subsequent culture conditions and large-scale production.