Conditions promoting effective very high gravity sugarcane juice fermentation

摘要: Applying very high gravity (VHG) fermentation conditions to the sugarcane juice (SCJ) bioethanol industry would improve its environmental and economic sustainability without need for major infrastructure changes or investments. It could enable a decrease in consumption of biological natural resources (cane/land, water energy) while maintaining acceptable production parameters. The present study attempts demonstrate characterise an effective industrially relevant SCJ-VHG process. An industry-like process with 30 35 °Bx broth was employed investigate effects both yeast strain used nitrogen source supplementation on yield, productivity, biomass viability, glycerol concentration retention-associated gene expression. Process performance shown be variably affected by different investigated. Highest efficiency, 17% (w/v) ethanol yield only 0.2% sugar remaining unfermented, observed Saccharomyces cerevisiae industrial CAT-1 30 °Bx urea supplementation. In addition, efficient retention identified as requisite better consistent higher expression permease STL1 channel FPS1. Urea promote deregulation expression, overcoming glucose repression. consistency between Fps1-mediated secretion extracellular media reinforces previous suggestions that might exit cell through Fps1 channel. This work brings solid evidence favour utilisation VHG conditions in SCJ fermentations, bringing it a step closer application. concentrated up maintains provided is supplemented suitable appropriate bioethanol-producing used. contributes understanding VHG-SCJ variable parameters efficiency response.