Unlike traditional energy crops, tobacco is characterized by its high content of water-soluble carbohydrates and nitrogen, low lignocellulose level, and strong tolerance to barren land conditions, especially on moderately to heavily saline-alkali soils. This makes it an ideal candidate for low-energy bioconversion processes.

A recent study by researchers at the Qingdao Institute of Bioenergy and Bioprocess Technology (QIBEBT) of the Chinese Academy of Sciences and the Tobacco Research Institute of the Chinese Academy of Agricultural Sciences (CAAS), along with international collaborators, have identified tobacco as a highly promising energy crop for biofuels and biochemicals production, harboring high capability of reducing greenhouse gas emissions.

Researchers designed a strategy that maximizes biomass conversion into bio-based products while minimizing energy and material inputs. By autoclaving tobacco leaves in water, they obtained a nutrient-rich medium. The medium can support the growth of microorganisms and the production of bioproducts, without needing for extensive pretreatment, hydrolysis, or additional supplements.

"This process dissolves over 65% of the biomass into a nutrient-rich medium without requiring extensive pretreatment," said Prof. ZHANG Haibo, one of the corresponding authors of this study and a researcher at QIBEBT.

The study marks a significant step forward in the development of low-carbon biorefineries and paves the way for future research and policy initiatives aimed at optimizing the use of tobacco in bioenergy applications.

"The ability to replace conventional synthetic media with tobacco medium in microbial fermentation processes helps open up new opportunities for the industrial-scale production of bioproducts in a more sustainable and cost-effective manner," said Prof. WANG Qian, a co-corresponding author of this study from the CAAS.

Life-cycle assessment showed that using tobacco could cut carbon emissions by up to 76% and reduce energy use by about 81% compared to traditional corn stover during biorefinery processes, according to their study.

This simple and viable technology of tobacco utilization will contribute to mitigating climate change, reducing environmental impact, and fostering a more sustainable future for generations to come, said Prof. Sang Yup Lee, another corresponding author who's from the Korea Advanced Institute of Science and Technology.

Results of the study were published in The Innovation on August 16.

Carbon Emission Life Cycle and Efficiency Comparison: Traditional vs. Tobacco Biorefinery (Image by WANG Fan)