In some embodiments, the invention provides a method for converting of a flue gas desulfurization (FGD) waste product to a gypsum-enriched product by fostering growth of sulfur oxidizing bacteria (SOB) in the FGD waste product. Also provided are isolated sulfur oxidizing bacteria cultures as well as kits comprising an isolated sulfur oxidizing bacteria culture and written instructions for fostering the growth of the isolated sulfur oxidizing bacteria culture in FGD waste product to product a gypsum-enriched product.

Genetically modified microorganisms useful in fermentation and methods of using such microorganisms are provided. Such microorganisms contain a [GAR+] prion or are modified to contain a [GAR+] prion. Exemplary microorganisms include yeast such as S. cerevisiae. The microorganisms can be further modified to convert xylose and/or arabinose. Methods of fermentation using such microorganisms exhibit improved fermentation efficiency and improved microorganism viability.

The present disclosure relates to using a source of one or more monosaccharides derived from a pulp or paper mill waste by-product for propagating microorganisms (e.g., yeast or bacteria). If desired, after propagation, the microorganisms can then be used to ferment one or more monosaccharides derived from a pulp or paper mill waste by-product into one or more biochemicals. Optionally, a stillage composition can be included in propagation medium to facilitate propagation and/or a stillage composition can be used to facilitate enzymatic hydrolysis of oligosaccharides and/or polysaccharides in a pulp or paper mill waste by-product to form monosaccharides.

The present disclosure relates to using a source of one or more monosaccharides derived from a pulp or paper mill waste by-product for propagating microorganisms (e.g., yeast or bacteria). If desired, after propagation, the microorganisms can then be used to ferment one or more monosaccharides derived from a pulp or paper mill waste by-product into one or more biochemicals. Optionally, a stillage composition can be included in propagation medium to facilitate propagation and/or a stillage composition can be used to facilitate enzymatic hydrolysis of oligosaccharides and/or polysaccharides in a pulp or paper mill waste by-product to form monosaccharides.

Methods for production of yeast biomass and removal of sugar from red liquor by propagating yeast on sugars in red liquor byproduct of the sulfite pulping process are disclosed. Yeast are propagated using the sugars in red liquor as a carbon source, thereby consuming the sugars and producing a composition of lignosulfonates that has a reduced sugar content. Disclosed methods allow for separation of sugars from lignosulfonates in red liquor without costly ultrafiltration or nanofiltration processes and also produce valuable yeast biomass.

Methods for production of yeast biomass and removal of sugar from red liquor by propagating yeast on sugars in red liquor byproduct of the sulfite pulping process are disclosed. Yeast are propagated using the sugars in red liquor as a carbon source, thereby consuming the sugars and producing a composition of lignosulfonates that has a reduced sugar content. Disclosed methods allow for separation of sugars from lignosulfonates in red liquor without costly ultrafiltration or nanofiltration processes and also produce valuable yeast biomass.

In some embodiments, the invention provides a method for converting of a flue gas desulfurization (FGD) waste product to a gypsum-enriched product by fostering growth of sulfur oxidizing bacteria (SOB) in the FGD waste product. Also provided are isolated sulfur oxidizing bacteria cultures as well as kits comprising an isolated sulfur oxidizing bacteria culture and written instructions for fostering the growth of the isolated sulfur oxidizing bacteria culture in FGD waste product to product a gypsum-enriched product.

In some embodiments, the invention provides a method for converting of a flue gas desulfurization (FGD) waste product to a gypsum-enriched product by fostering growth of sulfur oxidizing bacteria (SOB) in the FGD waste product. Also provided are isolated sulfur oxidizing bacteria cultures as well as kits comprising an isolated sulfur oxidizing bacteria culture and written instructions for fostering the growth of the isolated sulfur oxidizing bacteria culture in FGD waste product to product a gypsum-enriched product.