Sorghum (Sorghum bicolor L. Moench) and Its Main Parts (By-Products) as Promising Sustainable Sources of Value-Added Ingredients

Sorghum (Sorghum bicolor L. Moench) is a flowering plant in the grass family (Poaceae) characterized by a great genotypic and phenotypic diversity, making it a cereal species of major interest cultivated in warm climate worldwide. Fifth most cultivated cereal in the world and second in Africa, sorghum is the main cultivated species in the Sahelian zone. In 2020, its world and African estimated production were 58.7 and 27.5 million tonnes over an area of 40.3 and 27.3 million hectares, respectively. Primarily cultivated for its seeds, fodder, sugar and fiber, or for bioenergy production, sorghum is a staple food for millions of people. Its polymorphism gives it a versatile, multifunctional character and allows it to combine different food, energy and industrial uses. Mainly studied as a feedstock for the production of several chemicals and biofuels including bioethanol, biomethane, biohydrogen, biolipids, butyric and lactic acids, 1-butanol, acetone-butanol etc. and for electrical energy production in microbial fuel cells. The processes for exploiting the various components (starchy grains, lignocellulosic biomass and sweet juice extracted from the stem) of this plant generate a large quantity of by-products which are valued in many fields of application. Mainly as source of food and feed, biomolecules with therapeutic, nutraceutical and functional properties and for industrial or artisanal applications and biomaterials. The world population increasing combined with the decrease of biomass resources, due to the effects of climate change, imposed a reconsideration of the potential of the entire value chain of this crop. The present review focused on the biochemical composition of sorghum and its use as food but also as a source of valuable by-products. [GRAPHICS] .