Department of Food Biotechnology, Research Institute of Food Science and Technology (RIFST), Mashhad, Iran.
Department of Food Physics, Research Institute of Food Science and Technology (RIFST), Mashhad, Iran.
Sci Rep. 2024 Nov 4;14(1):26616. doi: 10.1038/s41598-024-77305-w.
Bacterial cellulose (BC) is a cellulosic biopolymer produced by specific acetic acid bacteria during kombucha fermentation. In this study, bacterial cellulose-producing strains were isolated from four different global kombucha SCOBY samples obtained from markets in the Netherlands, America, China, and Iran. The strains were identified using biochemical and molecular techniques. The ability of species to produce BC was evaluated under both static and stirred fermentation conditions. Seven dominant strains from the Acetobacteraceae family and the genus of Komagataeibacter and Gluconacetobacter were identified and submitted to NCBI gene bank archives: K. xylinus CH1, K. sucrofermentans IR2, K. intermedius IR3, K. cocois AM2, K. sucrofermentans NE4, K. cocois NE6, and G. liquefaciens NE7. Among these, K. intermedius IR3, isolated from local Iranian SCOBY, exhibited the highest BC production yield at 5.733 ± 0.170 gL under static fermentation conditions. On the other hand, K. xylinus CH1, from Chinese SCOBY, had the highest yield under stirred conditions, producing 12.689 ± 0.808 gL of BC. The BC production yield of both K. xylinus CH1 and K. intermedius IR3 under stirred conditions was 3 and 1.3 times more than static conditions, respectively. Despite the yield differences, static fermentation demonstrated superior physicochemical characteristics; such as moisture content, water holding capacity, and crystallinity degree, compared to stirred. Therefore, depending on the intended application in industry and specific criteria, both products could serve as functional substitutes in food and medicine sectors.
细菌纤维素（BC）是一种纤维素生物聚合物，由特定的醋酸菌在康普茶发酵过程中产生。在这项研究中，从来自荷兰、美国、中国和伊朗市场的四种不同全球康普茶 SCOBY 样本中分离出了产细菌纤维素的菌株。使用生化和分子技术对菌株进行了鉴定。在静态和搅拌发酵条件下评估了物种产生 BC 的能力。从醋酸菌科和Komagataeibacter 和Gluconacetobacter 属中鉴定出了 7 种优势菌株，并提交给 NCBI 基因库档案：K. xylinus CH1、K. sucrofermentans IR2、K. intermedius IR3、K. cocois AM2、K. sucrofermentans NE4、K. cocois NE6 和 G. liquefaciens NE7。其中，从当地伊朗 SCOBY 中分离出的 K. intermedius IR3 在静态发酵条件下表现出最高的 BC 产量，为 5.733 ± 0.170 g/L。另一方面，来自中国 SCOBY 的 K. xylinus CH1 在搅拌条件下具有最高的产量，产生 12.689 ± 0.808 g/L 的 BC。K. xylinus CH1 和 K. intermedius IR3 在搅拌条件下的 BC 产量分别比静态条件下高 3 倍和 1.3 倍。尽管产量存在差异，但与搅拌相比，静态发酵表现出更好的物理化学特性；例如，水分含量、持水能力和结晶度。因此，根据在工业中的预期应用和特定标准，这两种产品都可以作为食品和医药领域的功能性替代品。
