Standardising Cellulose Production From Acetobacter diazotrophicus

Abstract

Bacterial cellulose (BC) is a biopolymer that comes from natural sources. It has high purity, crystallinity, mechanical strength, and biocompatibility, which makes it suitable for various biomedical and industrial uses. Unlike plant cellulose, BC does not contain lignin or hemicellulose. This results in better material quality and simpler processing. However, producing BC on a large scale is limited by high production costs, expensive culture media, and dependence on a few bacterial strains. It is essential to find cost-effective production methods and alternative microbial sources to expand its commercial use. This study looked at the cellulose-producing ability of Acetobacter diazotrophicus, a safe and relatively unexplored bacterium, under different growth conditions. We compared bacterial growth and cellulose production using Hestrin-Schramm (HS) medium, the standard for BC production, and LB supplemented with glucose (LB+Glucose), which we explored as a more affordable option. We analyzed growth rates, inoculum age, and pH levels to find the best conditions for cellulose production. We observed faster bacterial growth in HS medium, with a doubling time of 3.906 hours, compared to 6.241 hours in LB+Glucose medium. Cellulose production was greatly affected by inoculum age, with successful synthesis from cultures that were agitated for 36 to 40 hours. The highest cellulose yield was at pH 6.0 in HS medium (4.6 mg/mL) and at pH 5.5 in LB+Glucose medium (3.6 mg/mL). FTIR analysis confirmed the presence of characteristic functional groups of bacterial cellulose. These results suggest that Acetobacter diazotrophicus is a promising and cost-effective option for producing bacterial cellulose and highlight the importance of medium composition, inoculum age, and pH for optimizing production.