Direct ethanol production from starch using a natural isolate, Scheffersomyces shehatae: Toward consolidated bioprocessing

Abstract

Consolidated bioprocessing (CBP), which integrates enzyme production, saccharification and fermentation into a one-step process, is a promising strategy for cost-effective ethanol production from starchy biomass. To gain insights into starch-based ethanol production using CBP, an extensive screening was undertaken to identify naturally occurring yeasts that produce ethanol without the addition of any amylases. Three yeast strains were capable of producing a significant amount of ethanol. Quantitative assays revealed that Scheffersomyces shehatae JCM 18690 was the strain showing the highest ethanol production ability. This strain was able to utilize starch directly, and the ethanol concentration reached 9.21 g/L. We attribute the ethanol-producing ability of this strain to the high levels of glucoamylase activity, fermentation potential and ethanol stress tolerance. This study strongly suggests the possibility of starch-based ethanol production by consolidated bioprocessing using natural yeasts such as S. shehatae JCM 18690.

Whole-genome de novo sequencing, combined with RNA-Seq analysis, reveals unique genome and physiological features of the amylolytic yeast Saccharomycopsis fibuligera and its interspecies hybrid

“…Intensive research efforts have recently been made in searching for and genome sequencing of microorganisms that secrete hydrolytic enzymes with high potential for applications in sectors such as the food, detergent, laundry, textile, baking, and biofuel industries [61, 62]. The distinctive genomic inventory of S. fibuligera , enriched in genes for extracellular hydrolytic enzymes, further supports the high potential of this amylolytic yeast to serve as an economical host for the production of industrial enzymes and bioproducts from renewable resources.…”

Bioethanol Production by Novel Indigenous Yeast Strains from Lignocellulosic Waste

“…Another related study by the ethanol concentration reached 9.21 g/L. Another study strongly suggests the possibility of starch-based ethanol production by consolidated bioprocessing using natural yeasts such as S. shehatae JCM 18690 [13][14][15][16].…”

Evaluation of Non-Saccharomyces Cerevisiae Strains Isolated from Sea Water Against Inhibitory Compounds for Ethanol Production

“…Yeast strains assimilate glucose and other monosaccharides derived from enzymatic hydrolysis of starch (Tanimura et al, 2015). The global trend of renewable energy uses various materials, such as those derived from lignocellulosic biomass including herbaceous and woody plants, agricultural and forestry residues, municipal solid waste and industrial waste streams (Van Wyk, 2001;Fujita et al, 2002;Tesfaw & Assefa 2014).…”