Utilization of inulin-containing waste in industrial fermentations to produce biofuels and bio-based chemicals

AbstractInulins are polysaccharides that belong to an important class of carbohydrates known as fructans and are used by many plants as a means of storing energy. Inulins contain 20 to several thousand fructose units joined by β-2,1 glycosidic bonds, typically with a terminal glucose unit. Plants with high concentrations of inulin include: agave, asparagus, coffee, chicory, dahlia, dandelion, garlic, globe artichoke, Jerusalem artichoke, jicama, onion, wild yam, and yacón. To utilize inulin as its carbon and energy sour ce directly, a microorganism requires an extracellular inulinase to hydrolyze the glycosidic bonds to release fermentable monosaccharides. Inulinase is produced by many microorganisms, including species ofAspergillus, Kluyveromyces, Penicillium, andPseudomonas. We review various inulinase-producing microorganisms and inulin feedstocks with potential for industrial application as well as biotechnological efforts underway to develop sustainable practices for the disposal of residues from processing inulin-containing crops. A multi-stage biorefinery concept is proposed to convert cellulosic and inulin-containing waste produced at crop processing operations to valuable biofuels and bioproducts usingKluyveromyces marxianus, Yarrowia lipolytica, Rhodotorula glutinis, andSaccharomyces cerevisiae as well as thermochemical treatments.
Source: World Journal of Microbiology and Biotechnology - Category: Microbiology Source Type: research