Abstract: Phosphate-regulated expression of recombinant glycoprotein antigens and other recombinant proteins in diatoms is described herein. More specifically, described herein is the expression and purification of glycosylated, immunogenic, and serologically active receptor-binding domain (RBD) of the SARS-CoV-2 spike protein, as well as SARS-CoV-2 nucleocapsid protein, in the marine pennate diatom Phaeodactylum tricornutum, as well as a functional lateral flow assay-based diagnostic device based on the produced recombinant RBD and nucleocapsid protein. Also described herein is the use of phosphate/iron levels in culture media to regulate expression/secretion of recombinant proteins under control of an HASP1 promoter in P. tricornutum or other suitable host cells. Also described herein is a method for increasing the expression/secretion of a recombinant protein by engineering the recombinant protein to lack a Tobacco Etch Virus (TEV) protease cleavage site.

Abstract: A method is provided for the treatment of waste streams resulting from the processing of hydrocarbons that contain naphthenic acids, for example desalter brine resulting from the extraction or production of hydrocarbons from an oil sands reservoir. Naphthenic acids can be removed from these streams by removing oil-wet solids from the waste stream prior to conventional waste water processing, and the oil-wet solids can further be independently remediated to reduce naphthenic acid concentration for disposal.

Abstract: A method is provided for the treatment of waste streams resulting from the processing of hydrocarbons that contain naphthenic acids, for example desalter brine resulting from the extraction or production of hydrocarbons from an oil sands reservoir. Naphthenic acids can be removed from these streams by removing oil-wet solids from the waste stream prior to conventional waste water processing, and the oil-wet solids can further be independently remediated to reduce naphthenic acid concentration for disposal.