Komagataeibacter intermedius V-05: An Acetic Acid Bacterium Isolated from Vinegar Industry, with High Capacity for Bacterial Cellulose Production in Soybean Molasses Medium
Rodrigo José Gomes1, Paula Cristina de Sousa Faria-Tischer2, Cesar Augusto Tischer2, Leonel Vinicius Constantino3, Morsyleide de Freitas Rosa4, Roberta Torres Chideroli5, Ulisses de Pádua Pereira5 and Wilma Aparecida Spinosa1*
1Department of Food Science and Technology, State University of Londrina, Celso Garcia Cid (PR 445) Road, 86057-970, Londrina, PR, Brazil
2Departament of Biochemistry and Biotechnology, State University of Londrina, Celso Garcia Cid (PR 445) road, 86057-970, Londrina, PR, Brazil
3Departament of Chemistry, State University of Londrina, Celso Garcia Cid (PR 445) road, 86057-970, Londrina, PR, Brazil
4Embrapa Agroindústria Tropical, 2270 Dra. Sara Mesquita road, 60511-110, Fortaleza, CE, Brazil
5Department of Veterinary Preventive Medicine, State University of Londrina, Celso Garcia Cid (PR 445) road, 86057-970, Londrina, PR, Brazil
Received: 19 January 2021
Accepted: 25 October 2021
bacterial isolation, acetic fermentation, soybean co-product, microbial polysaccharide, physicochemical characterization
Research background. Despite the great properties of bacterial cellulose, its manufacture is still limited due to difficulties in large-scale production. These problems are mainly related to low production yields and high overall costs of the conventional culture media normally used. To surpass these problems, it is necessary to identify new cheap and sustainable carbon sources. Thus, this work aims to isolate and select a high cellulose-producing Komagataeibacter strain from vinegar industry, and study its potential for bacterial cellulose synthesis in an industrial soybean co-product, known as soybean molasses, used as fermentation medium.
Experimental approach. One isolated strain was able to produce high amount of cellulose in the standard Hestrin-Schramm medium, so we tested its ability to produce this biopolymer in a soybean molasses medium. The characteristics and properties of the produced bacterial cellulose membranes were analyzed by thermogravimetric analysis, X-ray diffraction, infrared spectroscopy, water-holding capacity and rehydration ratio. Genetic analysis of the selected strain served to determine its genus and species.
Results and conclusions. An isolated strain that produced the highest amount of cellulose in Hestrin-Schramm medium (3.7 g/L) was genetically identified as Komagataeibacter intermedius V-05. This strain produced 10.0 g/L of cellulose in soybean molasses medium. Membranes from both substrates had similar chemical structure, crystallinity and thermal degradation. Soybean molasses proved to be a suitable alternative medium for biosynthesis of cellulose in comparison with the standard medium. In addition to providing higher production yield, the membranes showed great structural characteristics, similar to those obtained from standard medium.
Novelty and scientific contribution. In this research, we have isolated and identified a Komagataeibacter strain which exhibits a high capacity for cellulose production in soybean molasses. The isolation and selection of strains with high capacity for microbial metabolite production is important for decreasing bioprocess costs. Furthermore, as there is a necessity today to find cheaper carbon sources to obtain microbial products at a lower cost, soybean molasses represents an interesting alternative medium to produce bacterial cellulose for its industrial application.