Influence of 1-methylcyclopropene (1-MCP) on the production of bacterial cellulose biosynthesized by Acetobacter xylinum under the agitated culture

Aims: Bacterial cellulose is an extracellular polysaccharide secreted by Acetobacter xylinum, which has become a novel material increasingly used in food and medical industries. However, its broad application is limited by its low yield and high cost. 1-Methylcyclopropene (1-MCP) is a potent inhibitor to either exogenous or endogenous ethylene during the biological senescence of plants, which has been broadly applied in commercial preservation of fruits and vegetables. The purpose of this study was to investigate the effects of 1-MCP on both the growth of Acet. xylinum and its cellulose production to demonstrate the potential enhancement of bacterial cellulose yield. Methods and Results: Three groups of samples were fermented under agitated culture with 125 rev min-1 rotational speed. To the culture media, 0 center dot 14 mg of 1-MCP contained in 100 mg dextrose powder was added on assigned days or on the first culture day only. Results from the measurement of bacterial cell concentration and bacterial cellulose yield at the end of a 12-day culture demonstrated that cultures excluding 1-MCP displayed a higher cell concentration and a lower cellulose production, while cultures containing 1-MCP produced 15 center dot 6% more cellulose (1-MCP added on day 1) and 25 center dot 4% (1-MCP added on each assigned day) with less biomass. Conclusions: 1-MCP was able to affect the growth of Acet. xylinum cells and resulted in increasing bacterial cellulose yield up to 25 center dot 4% over controls, which did not contain 1-MCP. Significance and Impact of the Study: This was the first study to use the growth inhibitor of plants to investigate its effects on bacterial growth and production. It also demonstrated a significant enhancement of bacterial cellulose yield by the addition of 1-MCP during the common agitated culture of Acet. xylinum.