Agriculture and agro-Industrial wastes, byproducts, and wastewaters: origin, characteristics, and potential in bio-based-compounds production

A survey of the origin, characteristics and possible re-uses of various agriculture and agro-industrial wastes and wastewaters is given. By-products and effluents often contain substances of high-added value that can be directly recovered or can represent a zero- or low-cost substrate for fermentation processes aimed at producing bio-fuels or bio-molecules of actual or potential commercial interest. At first, focus has been put on the general upgrading criteria and strategies. Then, a number of examples have been reported and examined concerning wastes and wastewaters such as residual agricultural and agro-industrial biomasses, relevant effluents (i.e., slaughterhouse, winery and starch industry wastewaters and whey) and by-products of the olive-oil extraction industry.