The invention relates to a process for the production of ethanol, the process comprising fermenting of a carbon source composition with a recombinant yeast,

wherein the carbon source composition comprises at least glucose and arabinose; and
wherein the recombinant yeast comprises arabinose isomerase activity, ribulokinase activity, ribulose phosphate epimerase activity, glycerol uptake activity and glycerol conversion capacity; and
wherein the recombinant yeast further comprises a genetic modification leading to the reduction, downregulation, inhibition and/or elimination of the activity of a homologous protein with glycerol-efflux activity; and
wherein each of the glucose and the arabinose is converted into ethanol.

In addition, the invention relates to a recombinant yeast that can be used in such a process.

The present invention relates to polypeptides which are Gal2 variants comprising at least one amino acid substitution at a position corresponding to T354, and optionally further amino acid substitution(s). The present invention further relates to nucleic acid molecules encoding the polypeptides and to host cells containing said nucleic acid molecules. The present invention further relates to a method for the production of bioethanol and/or other bio-based compounds, comprising the expression of said nucleic acid molecules, preferably in said host cells. The present invention also relates to the use of the polypeptides, nucleic acids molecule or host cells for the production of bioethanol and/or other bio-based compounds, and/or for the recombinant fermentation of biomaterial containing pentose(s), preferably D-xylose and/or L-arabinose.

The present invention relates to polypeptides which are Gal2 variants comprising at least one amino acid substitution at a position corresponding to M435, and optionally further amino acid substitution(s). The present invention further relates to nucleic acid molecules encoding the polypeptides and to host cells containing said nucleic acid molecules. The present invention further relates to a method for the production of bioethanol and/or other bio-based compounds, comprising the expression of said nucleic acid molecules, preferably in said host cells. The present invention also relates to the use of the polypeptides, nucleic acids molecule or host cells for the production of bioethanol and/or other bio-based compounds, and/or for the recombinant fermentation of biomaterial containing pentose(s), preferably D-xylose and/or L-arabinose.

The present invention relates to polypeptides which are Gal2 variants comprising at least one amino acid substitution at a position corresponding to T354, and optionally further amino acid substitution(s). The present invention further relates to nucleic acid molecules encoding the polypeptides and to host cells containing said nucleic acid molecules. The present invention further relates to a method for the production of bioethanol and/or other bio-based compounds, comprising the expression of said nucleic acid molecules, preferably in said host cells. The present invention also relates to the use of the polypeptides, nucleic acids molecule or host cells for the production of bioethanol and/or other bio-based compounds, and/or for the recombinant fermentation of biomaterial containing pentose(s), preferably D-xylose and/or L-arabinose.

The present invention relates to a method for preparing tagatose from residue after extracting coffee, comprising: obtaining a hydrolysate by hydrolyzing residue after extracting coffee into acid; obtaining a hydrolysate refined by decolorization and ion-refining the obtained hydrolysate; and obtaining tagatose by isomerizing the refined hydrolysate to an arabinose isomerase.

The present application discloses the identification of the novel K. marxianus xylose transporter genes KHT105 and RAG4, as well as the identification of a novel set of I. orientalis pentose phosphate pathway genes The present application further discloses a series of genetically modified yeast cells comprising various combinations of arabinose fermentation pathways, xylose fermentation pathways, pentose phosphate pathways, and/or xylose transporter genes, and methods of culturing these cells to produce ethanol in fermentation media containing xylose.

The present invention relates to polypeptides which are Gal2 variants comprising at least one amino acid substitution at a position corresponding to M435, and optionally further amino acid substitution(s). The present invention further relates to nucleic acid molecules encoding the polypeptides and to host cells containing said nucleic acid molecules. The present invention further relates to a method for the production of bioethanol and/or other bio-based compounds, comprising the expression of said nucleic acid molecules, preferably in said host cells. The present invention also relates to the use of the polypeptides, nucleic acids molecule or host cells for the production of bioethanol and/or other bio-based compounds, and/or for the recombinant fermentation of biomaterial containing pentose(s), preferably D-xylose and/or L-arabinose.

The present invention relates to a method for preparing tagatose from residue after extracting coffee, comprising: obtaining a hydrolysate by hydrolyzing residue after extracting coffee into acid; obtaining a hydrolysate refined by decolorization and ion-refining the obtained hydrolysate; and obtaining tagatose by isomerizing the refined hydrolysate to an arabinose isomerase.