The use of fungi for bioconversion of distillery waste into microbial biomass or some useful metabolites is reviewed. Stillages remaining in alcohol distilleries, although based on different raw materials have the common characteristic in that they are highly loaded effluents, which are difficult to purify. They are harmful to the environment due to the high content of organic substances and low pH. However, these properties facilitate their use as substrates for fungal growth. Sugarcane molasses stillages have been used for the most part. Among fungi, yeasts, especially C. utilis, predominate. To a minor extent filamentous fungi, including Basidiomycetes, as well as mixed fungal or mixed fungal and bacterial cultures have been used. Laboratory, pilot scale, and industrial scale experiments have been performed, and batch or continuous, single- or two-step fermentations have been introduced. The end products of bioconversion are fungal biomass and substantially purified and decolorized effluents. A well-balanced amino acid composition makes the biomass suitable as an animal feed supplement. In addition to biomass other products can be obtained, such as ethanol, enzymes, polysaccharides, pigments, and plant growth hormones. The economics of stillage bioconversion with fungi is dependent on many different factors and can vary from country to country. However, the conclusion is that fungi have a great potential in helping to solve pollution problems and, at the same time, producing marketable products.
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