Towards high-temperature fuel ethanol production using Kluyveromyces marxianus: On the search for plug-in strains for the Brazilian sugarcane-based biorefinery

Author(s)

Madeira-Jr, Jose Valdo ; Gombere, Andreas Karoly ^[1]

Affiliation

^[1] Madeira-Jr, Jr., Jose Valdo, Univ Estadual Campinas, Sch Food Engn, Rua Monteiro Lobato 80, BR-13083862 Campinas, SP - Brazil

• Document type: Journal article
• Source: BIOMASS & BIOENERGY; v. 119, p. 217-228, DEC 2018.
• Web of Science Citations: 5

Abstract

In the production of fuel ethanol from sugarcane in Brazilian biorefineries, one way to achieve lower production costs is the fermentation of sugars into ethanol at high temperatures (similar to 48 degrees C), which could lead to a decrease in: contamination levels, use of antibiotics, cooling costs, water usage, use of sulphuric acid in cell recycling, and energy used in distillation. Since Saccharomyces cerevisiae, the yeast species used in these biorefineries, cannot grow at these temperatures, alternative organisms need to be employed and one candidate is Kluyveromyces marxianus. Here, 20 strains belonging to this species were screened for their capacity to thrive at high temperatures (37, 45 and 48 degrees C) and under conditions relevant in the fuel ethanol industry: low pH (2.5), anaerobiosis, and high ethanol concentrations (up to 10%). The ethanol producing capacity of some strains was also evaluated and the ethanol yield on sugar quantified. Strains K. marxianus NCYC 3396 and UFV-3 stood out as potential microorganisms to be plugged into this industry (metabolic, evolutionary and reverse engineering will be required), since they grew better than the remaining ones under most of the conditions tested and produced ethanol at 48 degrees C with similar yields (0.40 g ethanol.g glucose(-1)) to those displayed by S. cerevisiae at 37 degrees C. (AU)

• FAPESP's process: 16/23606-0 - Towards a Kluyveromyces marxianus strain suitable for non-aseptic fuel ethanol production at high temperature
• Grantee: José Valdo Madeira Junior
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• FAPESP's process: 15/26072-3 - Fuel ethanol production by the fastest eukaryote on the planet
• Grantee: José Valdo Madeira Junior
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 15/14109-0 - Fuel ethanol production by the fastest eukaryote on the planet
• Grantee: Andreas Karoly Gombert
• Support Opportunities: Regular Research Grants