Effects of inorganic salts on biomass production, cell wall components, and bioethanol production in Nicotiana tabacum

The development of bioenergy through biomass has gained importance due to the increasing rates of fossil fuel depletion. Biomass is important to increase the productivity of bioethanol, and production of biomass with high biomass productivity, low lignin content, and high cellulose content is also important in this regard. Inorganic salts are important in the cultivation of biomass crops for the production of biomass with desirable characteristics. In this study, the roles of various inorganic salts in biomass and bioethanol production were investigated using an in vitro tobacco culture system. The inorganic salts evaluated in this study showed dramatic effects on tobacco plant growth. For example, H2PO4 substantially improved plant growth and the root/shoot (R/S) ratio. The chemical compositions of tobacco plants grown in media after removal of various inorganic salts also showed sig- nificant differences; for example, lignin content was high after Mg2+ removal treatment and low after K+ treatment and H2PO4 removal treatment. On the other hand, NO3- and H2PO4 treatments yielded the highest cellulose while enzymatic hydrolysis yielded the highest glucose concentration ratio 24 h after NH4+ removal treatment. The ethanol productivity after H2PO4 removal treatment was 3.95% (w/v) 24 h after fermentation and 3.75% (w/v) after 36 h. These results can be used as the basis for producing high-quality biomass for future bioethanol production.