Sustainable production of bacterial nanocellulose from date fruit waste using Bacillus haynesii for waste valorisation and crystal violet dye removal.

Growing concerns about pollution caused by industrial and agricultural wastes have increased interest in converting waste materials into useful products. Bacterial nanocellulose has garnered global interest due to its environmentally friendly production, excellent mechanical properties, and biocompatibility, making it a promising material for various industries. This study explores the production of bacterial nanocellulose (BNC) by Bacillus strains utilizing fruit waste as a sustainable carbon source. Six potential BNC-producing Bacillus strains were isolated and identified. Among them, Bacillus haynesii showing the highest BNC productivity. A Box-Behnken experimental design was employed to optimize cost-effective technique for BNC production. Key factors like temperature, date waste extract percentage, and initial pH level influencing bacterial cellulose production by Bacillus haynesii were optimized. The highest BNC productivity with a value of 2.6 g/L was obtained under optimized conditions of 29 °C, 15% date waste extract, and pH 6. The glass transition temperature of the bacterial nanocellulose ranged from 21.51 to 42.06 °C, with a low negative charge for colloidal stability. Moreover, crystal violet elimination experiments revealed efficient dye removal (84.7%) with adsorbent concentrations of 2 mg/L and a contact time of 60 min. This study concluded that the Bacillus haynesii 9.1AP strain is a promising candidate for sustainable BNC production. To the best of our knowledge, this study represents the initial documentation of Bacillus haynesii's capability for BNC production, highlighting its potential in environmental and industrial applications, particularly in dye adsorption.