Isolation of Bacterial Cellulose Nanofibers Producing Acetic Acid Bacteria from Fermented juices

Bacterial cellulose (BC) are high purity, ultra-fine network of nanofibrils structure, and non-toxic. The nanofibrils bacterial cellulose used for many applications in the food, medical and cosmetics industries. The objectives of this study aim to isolate and identify of nanofibrils bacterial cellulose producing acetic acid bacteria (AAB). We studied, isolation of cellulose producing AAB from 26 samples of Kombucha culture and different kinds of fermented fruit, and herb juices on Histrin Schramm. One hundred and seventeen bacterial isolates were obtained. The isolates were tested for their biochemical characteristics and bacteria cellulose nanofibrils production. Four isolates: RC1, RC3, RJ1, and RG2 were found to produce highest of bacteria cellulose (approximately 9-11 mm) from 1% (v/v) concentration of acetic acid in HS broth. The morphology and nanofibers were investigated by SEM and XRD, the bacterial cellulose nanofibrils size was 4.10, 4.95, 4.38, and 4.91 nm, respectively. However, isolates RJ1, RC3, and RC1 were identified to Komagataeibacter hansenii and then, isolates RG2 was identified to K. maltaceti.细菌纤维素（Bacterial cellulose，BC）具有高纯度、超细纳米纤维网络结构，且无毒性。该纳米纤维状细菌纤维素可应用于食品、医药及化妆品等多个工业领域。本研究旨在分离并鉴定产纳米纤维细菌纤维素的醋酸菌（Acetic Acid Bacteria，AAB）：借助赫斯特林-施拉姆（Hestrin-Schramm）培养基，从26份康普茶（Kombucha）发酵液样本、多种发酵果汁及草本汁液中分离产纤维素醋酸菌，共获得117株细菌分离株。对上述分离株的生化特性与细菌纳米纤维纤维素合成能力进行了检测。在醋酸浓度为1%（体积分数）的HS肉汤培养基中，RC1、RC3、RJ1与RG2共4株分离株的细菌纤维素产量最高，约为9~11 mm。通过扫描电子显微镜（Scanning Electron Microscope，SEM）与X射线衍射（X-ray Diffraction，XRD）对其形态及纳米纤维结构进行表征，各分离株对应的细菌纳米纤维纤维素尺寸分别为4.10、4.95、4.38及4.91 nm。经鉴定，RJ1、RC3与RC1菌株为汉逊葡糖醋杆菌（Komagataeibacter hansenii），RG2菌株则为麦芽糖葡糖醋杆菌（Komagataeibacter maltaceti，简称K. maltaceti）。