| Abstract |
The population growth and increasing economic activities have impacted on the environment, indicating the need to change from linear to circular business models which are sustainable and resource efficient. One of the circular economy drivers is the use of waste as raw materials in the industry, reducing environmental impacts and process costs. Crude glycerol and corn steep liquor are low-cost industrial by-products that can become waste when produced in a large amount. The present study proposes using crude glycerol and corn steep liquor as raw materials for 1,3-propanediol production by Clostridium butyricum NCIMB 8082. 1,3-Propanediol is an important molecule, being mainly used for polymer synthesis. Clostridium butyricum NCIMB 8082 was able to grow in a culture medium containing only crude glycerol and corn steep liquor, achieving 0.51 g.g- 1 of 1,3-propanediol yield and 6.56 g.L-1 1,3-propanediol after 24 h of fermentation in 65 mL serum glass bottle with no pH control. A 5-L batch fermentation was performed in a culture medium containing only crude glycerol, corn steep liquor and KH2PO4. 1,3-Propanediol concentration reached 28.26 g.L-1 after 16 h of glycerol fermentation, achieving 1.71 g.L-1.h-1 of 1,3-propanediol productivity and 0.49 g.g- 1 of 1,3-propanediol yield. Besides, acetic and butyric acids were also produced in all studied conditions. |
