Fermentation of biomass sugars to ethanol using native industrial yeast strains

Yuan, Dawei; Rao, Kripa; Relue, Patricia A.; Varanasi, Sasidhar

doi:10.1016/j.biortech.2010.11.034

Cited by 35 publications

(35 citation statements)

References 25 publications

(22 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Using the latter ethanol yield calculation method, the total amount of nutrients used to produce the reported ethanol concentrations was obtained by assuming that 1 g dry cell weight of the inoculum required 2 g glucose or other nutrient, which conservatively estimates the nutrients used . The ethanol yield for the extracellular xylose isomerase urea system dropped to 0.12 g/g, due to the very high yeast inoculum . The ethanol yield of 0.35 g/g reported for one of the extracellular xylose isomerase system is this research group's prior work (Figure D), and the xylose was not completely consumed; however, the total added glucose and xylose were used to determine the yield.…”

Section: Resultsmentioning

confidence: 90%

“…In this study, approximately 140 ± 10 g/L glucose and 70 ± 5 g/L xylose were added to the fermentation vessel and 78 ± 3 g/L ethanol was obtained (Figure B). The literature data for maximum ethanol concentrations were 70 g/L for extracellular xylose isomerase systems and 60 g/L for the recombinant S. cerevisiae systems . The two‐stage fermentation using S. pastorianus has comparable maximum ethanol concentrations, indicating good ethanol tolerance.…”

Section: Resultsmentioning

confidence: 98%

“…In comparison, the highest ethanol yield reported for the extracellular xylose isomerase systems was 0.37 g/g. Although the immobilized xylose isomerase with urea system had a very high ethanol to sugar yield for the fermentation, it would also have significant operating costs for the immobilization process (Figure C) . The highest ethanol yield for many recent recombinant system publications was 0.32 g/g, where the most recent works have reported up to 0.42 g/g .…”

Section: Resultsmentioning

confidence: 99%

See 2 more Smart Citations

Novel two‐stage fermentation process for bioethanol production using Saccharomyces pastorianus

Gowtham

Miller

Hodge

et al. 2014

Biotechnology Progress

View full text Add to dashboard Cite

Bioethanol produced from lignocellulosic materials has the potential to be economically feasible, if both glucose and xylose released from cellulose and hemicellulose can be efficiently converted to ethanol. Saccharomyces spp. can efficiently convert glucose to ethanol; however, xylose conversion to ethanol is a major hurdle due to lack of xylose-metabolizing pathways. In this study, a novel two-stage fermentation process was investigated to improve bioethanol productivity. In this process, xylose is converted into biomass via non-Saccharomyces microorganism and coupled to a glucose-utilizing Saccharomyces fermentation. Escherichia coli was determined to efficiently convert xylose to biomass, which was then killed to produce E. coli extract. Since earlier studies with Saccharomyces pastorianus demonstrated that xylose isomerase increased ethanol productivities on pure sugars, the addition of both E. coli extract and xylose isomerase to S. pastorianus fermentations on pure sugars and corn stover hydrolysates were investigated. It was determined that the xylose isomerase addition increased ethanol productivities on pure sugars but was not as effective alone on the corn stover hydrolysates. It was observed that the E. coli extract addition increased ethanol productivities on both corn stover hydrolysates and pure sugars. The ethanol productivities observed on the corn stover hydrolysates with the E. coli extract addition was the same as observed on pure sugars with both E. coli extract and xylose isomerase additions. These results indicate that the two-stage fermentation process has the capability to be a competitive alternative to recombinant Saccharomyces cerevisiae-based fermentations.

show abstract

Section: Resultsmentioning

confidence: 90%

Section: Resultsmentioning

confidence: 98%

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Novel two‐stage fermentation process for bioethanol production using Saccharomyces pastorianus

Gowtham

Miller

Hodge

et al. 2014

Biotechnology Progress

View full text Add to dashboard Cite

show abstract

“…Lignocellulosic biomass has been considered a promising substrate for the production of bio ethanol (Balat and Balat 2009; Sanchez and Cardona 2008). One of the major impediments in utilizing lignocellulosic biomass as a feedstock is the inability of many yeasts to utilize both the hexose and pentose sugars, which are the principal components of hydrolysates from lignocellulose (Yuan et al 2011; Tian et al 2009; Sanchez and Cardona 2008). The ability of yeasts to metabolize these hexoses and pentoses has been studied widely.…”

Section: Introductionmentioning

confidence: 99%

Production of ethanol and arabitol by Debaryomyces nepalensis: influence of process parameters

2013

View full text Add to dashboard Cite

Debaryomyces nepalensis, osmotolerant yeast isolated from rotten apple, is known to utilize both hexoses and pentoses and produce industrially important metabolites like ethanol, xylitol and arabitol. In the present study, the effect of different growth substrates, trace elements, nitrogen concentration and initial pH on growth and formation of ethanol and arabitol were examined. Optimum conditions for maximizing the product yields were established: glucose as carbon source, an initial pH of 6.0, 6 g/L of ammonium sulphate and addition of micronutrients. Under these best suited conditions, a concentration of 11g/L of arabitol and 19 g/L of ethanol was obtained in shake flask fermentations. The fermentation was scaled up to 2.5 L bioreactor and the influence of aeration, agitation and initial substrate concentration was also determined. Under optimal conditions (150 g/L glucose, 400 rpm and 0.5 vvm) ethanol concentration reached 52 g/L, which corresponds to a yield of 0.34 g/g and volumetric productivity of 0.28 g/L/h, whereas arabitol production reached a maximum of 14 g/L with a yield and volumetric productivity of 0.1 g/g and 0.07 g/L/h respectively.

show abstract

“…The µMAX value of 0.20 h -1 , was relatively low when compared with the results that have been obtained in other studies and indicates that cell growth is slow under assessed conditions. This fact is likely associated with the low biomass of the inocula (Duarte et al 2008;Yuan et al 2011). …”

Section: Resultsmentioning

confidence: 99%

Cultivation of Trichosporon mycotoxinivorans in sugarcane bagasse hemicellulosic hydrolyzate

Matos¹,

Cassa-Barbosa²,

Neto³

et al. 2012

Electro Journal of Biotech

View full text Add to dashboard Cite

Background: The yeast strain IB09 was isolated from the gut of Calosoma sp. (Carabidae, Coleoptera, Insecta) that were collected in the central Amazon rainforest. First, tolerance of the strain to ethanol and heat was tested. Then, IB09 was cultivated in a medium using sugarcane bagasse hemicellulosic hydrolyzate as a carbon source, and cell growth (OD600), specific growth rate (μMAX, h -1 ), biomass yield (YB, g.g -1 ) and relative sugar consumption (RSC, %) were evaluated. Taxonomic identification was determined by sequencing the ITS1 region of IB09 and comparing it to sequences obtained from the GenBank database (NCBI). Results: IB09 showed both ethanol tolerance and thermotolerance. Relative sugar consumption indicated that IB09 was able to perform saccharification of sugarcane bagasse hemicellulosic hydrolyzate, increasing the total reducing sugar concentration by approximately 50%. The μMAX value obtained was 0,20, indicating that cell growth was slow under the assessed conditions. Biomass yield was 0,701 g per g of consumed sugar, which is relatively high when compared with other findings in the literature. After 120 hrs of cultivation, 80,1% of total reducing sugar had been consumed. Sequencing of the ITS1 region identified IB09 as Trichosporon mycotoxinivorans. Conclusion: This is the first report to document this species in the central Amazon rainforest at this host. Trichosporon mycotoxinivorans has great biotechnological potential for use in the saccharification of sugarcane bagasse hemicellulosic hydrolyzate and for biomass production with this substrate as carbon source.

show abstract

Fermentation of biomass sugars to ethanol using native industrial yeast strains

Cited by 35 publications

References 25 publications

Novel two‐stage fermentation process for bioethanol production using Saccharomyces pastorianus

Novel two‐stage fermentation process for bioethanol production using Saccharomyces pastorianus

Production of ethanol and arabitol by Debaryomyces nepalensis: influence of process parameters

Cultivation of Trichosporon mycotoxinivorans in sugarcane bagasse hemicellulosic hydrolyzate

Contact Info

Product

Resources

About