Optimization and Characterization of a Novel Exopolysaccharide from <i>Bacillus haynesii</i> CamB6 for Food Applications
Aparna Banerjee,
Sura Jasem Mohammed Breig,
Aleydis Gómez,
Ignacio Sánchez-Arévalo,
Patricio González-Faune,
Shrabana Sarkar,
Rajib Bandopadhyay,
Sugunakar Vuree,
Jorge Cornejo,
Jaime Tapia,
Gaston Bravo,
Gustavo Cabrera-Barjas
Affiliations
Aparna Banerjee
Centro de Investigación de Estudios Avanzados del Maule, Vicerrectoría de Investigación y Posgrado, Universidad Católica del Maule, Talca 3466706, Chile
Sura Jasem Mohammed Breig
Department of Biochemical Engineering, Al-khawarizmi Collage of Engineering, University of Baghdad, Baghdad 10011, Iraq
Aleydis Gómez
Centro de Biotecnología de los Recursos Naturales (CENBio), Facultad de Ciencias Agrarias y Forestales, Universidad Católica del Maule, Talca 3466706, Chile
Ignacio Sánchez-Arévalo
Escuela de Ingeniería en Biotecnología, Facultad de Ciencias Agrarias y Forestales, Universidad Católica del Maule, Talca 3466706, Chile
Patricio González-Faune
Escuela de Ingeniería en Biotecnología, Facultad de Ciencias Agrarias y Forestales, Universidad Católica del Maule, Talca 3466706, Chile
Shrabana Sarkar
Centro de Investigación de Estudios Avanzados del Maule, Vicerrectoría de Investigación y Posgrado, Universidad Católica del Maule, Talca 3466706, Chile
Rajib Bandopadhyay
UGC Center of Advanced Study, Department of Botany, The University of Burdwan, Burdwan 713104, India
Sugunakar Vuree
Department of Biotechnology, School of Bioengineering and Biosciences, Lovely Professional University, Phagwara 144411, India
Jorge Cornejo
Institute of Chemistry and Natural Resources, Universidad de Talca, Talca 3460000, Chile
Jaime Tapia
Institute of Chemistry and Natural Resources, Universidad de Talca, Talca 3460000, Chile
Gaston Bravo
Unidad de Desarrollo Tecnológico (UDT), Universidad de Concepción, Av. Cordillera 2634, Parque Industrial Coronel, Coronel 3349001, Chile
Gustavo Cabrera-Barjas
Unidad de Desarrollo Tecnológico (UDT), Universidad de Concepción, Av. Cordillera 2634, Parque Industrial Coronel, Coronel 3349001, Chile
Extremophilic microorganisms often produce novel bioactive compounds to survive under harsh environmental conditions. Exopolysaccharides (EPSs), a constitutive part of bacterial biofilm, are functional biopolymers that act as a protecting sheath to the extremophilic bacteria and are of high industrial value. In this study, we elucidate a new EPS produced by thermophilic Bacillus haynesii CamB6 from a slightly acidic (pH 5.82) Campanario hot spring (56.4 °C) located in the Central Andean Mountains of Chile. Physicochemical properties of the EPS were characterized by different techniques: Scanning electron microscopy- energy dispersive X-ray spectroscopy (SEM-EDS), Atomic Force Microscopy (AFM), High-Performance Liquid Chromatography (HPLC), Gel permeation chromatography (GPC), Fourier Transform Infrared Spectroscopy (FTIR), 1D and 2D Nuclear Magnetic Resonance (NMR), and Thermogravimetric analysis (TGA). The EPS demonstrated amorphous surface roughness composed of evenly distributed macromolecular lumps. GPC and HPLC analysis showed that the EPS is a low molecular weight heteropolymer composed of mannose (66%), glucose (20%), and galactose (14%). FTIR analysis demonstrated the polysaccharide nature (–OH groups, Acetyl groups, and pyranosic ring structure) and the presence of different glycosidic linkages among sugar residues, which was further confirmed by NMR spectroscopic analyses. Moreover, D-mannose α-(1→2) and α-(1→4) linkages prevail in the CamB6 EPS structure. TGA revealed the high thermal stability (240 °C) of the polysaccharide. The functional properties of the EPS were evaluated for food industry applications, specifically as an antioxidant and for its emulsification, water-holding (WHC), oil-holding (OHC), and flocculation capacities. The results suggest that the study EPS can be a useful additive for the food-processing industry.
