Value added products from fermentation of sugars derived from agro-food residues

The use of renewable and environmentally sustainable agro-food residues as raw material for the production of bio-based products has gained interest recently. For this purpose, the application of a suitable pretreatment to improve biomass digestibility and the optimization of biomass hydrolysis for the production of fermentable sugars is crucial to make bio-based products competitive with petroleum-based ones. The combination of pretreatments together with the employment of microorganisms tolerant to inhibitors generated during the pretreatment or able to ferment pentose sugars in hydrolysates have turned out to be interesting approaches. Regarding hydrolysis and fermentation, SHF and SSF are the predominant strategies, although CBP and SSCF have gained recognition recently. The final bioproduct cost depends on the productivity, yield per quantity of substrate, cost of raw material and the recovery method. In this way, for the commercialization of these bioproducts, some technical challenges are still needed, including the reduction of the pretreatments and enzymes costs, the design of strains with tailored capabilities, downstream processes optimization, waste treatment, etc.