Abstract: The present invention relates to a method for a dicarboxylic acid, which method comprises fermenting fungal cells in a vessel comprising a suitable fermentation medium, wherein a least a portion of the fungal cells are reused in the presence of a vitamin and/or a trace element.

Abstract: Process for producing a dicarboxylic acid comprising fermenting a microorganism in a suitable fermentation medium wherein a gas flow comprising 30% to 100% v/v oxygen as measured under atmospheric pressure is added to the fermentation medium and producing the dicarboxylic acid.

Abstract: The present invention relates to a process for recovering succinic acid in crystal form from a fermentation broth comprising succinic acid, comprising the steps of a) bringing the fermentation broth to a pH of between 1 and 4, b) crystallizing the succinic acid from the fermentation broth to form succinic acid crystals, c) dissolving the succinic acid crystals at a temperature of between 30 and 90 degrees Celsius to form an aqueous solution comprising dissolved succinic acid, d) crystallizing the succinic acid from the solution to recover succinic acid in crystal form. The invention further relates to succinic acid in crystal form, comprising a sugar content of 1 to 100 ppm and a nitrogen content of 1 to 80 ppm.