• Journal of Microbiology and Biotechnology
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• v.4 no.1
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• pp.56-62
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• 1994

A yeast strain, BT001, which can directly ferment D-xylose to ethanol was isolated from forest soils, and then identified as Candida sp. Cultural conditions for the optimum ethanol production, along with the effects of aeration on cell growth and ethanol production were investigated. Aeration stimulated the cell growth and the volumetric rate of ethanol production, but decreased the ethanol yield. Optimum temperature and initial pH for the ethanol production were $33{\circ}^C$ and 6.0, respectively. In a shake flask culture, this strain produced 52.3 g ethanol per liter from 12%(w/v) D-xylose after incubation for 96 hours. Ethanol yield was 0.436 g per g D-xylose consumed. This corresponds to 85.8% of theoretical yield. Also, this yeast strain produced ethanol from D-galactose, D-glucose and D-mannose, but not from L-arabinose and L-rhamnose. Among these sugars, D-glucose was the fastest in being converted to ethanol sugars.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.4
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• pp.401-408
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• 2012

The grain and agronomic characteristics of Korean barley cultivars were investigated with respect to ethanol yield. Test weight, grain yield, and starch yield showed noticeable variation among the cultivars. Grain yields were higher in covered barley and non-waxy barley. Starch yield was higher in non-waxy barley than waxy barley. Protein, ${\beta}$-glucan, and starch content of tested cultivars ranged in 10.0-12.9%, 4.4-7.5% and 49.7-65.3%, respectively. Naked barley cultivar had higher starch content than covered barley cultivar. However, covered barley had high starch yield because it has higher grain yield than naked barley. Covered barley cultivar had higher husk content, ranging 7.6-14.0%, than that of naked barley cultivar, ranging 5.3-8.0%. Starch content was positively correlated with amylose content, test weight, ethanol yield and negatively correlated with protein, husk, ${\beta}$-glucan content. Ethanol yield per ton was positively correlated with starch content, but negatively correlated with husk content. Ethanol yield per hectare was positively correlated with starch yield, grain yield, grain weight and negatively correlated with protein, test weight. From this research, the important characteristics of barley cultivar as a bioethanol producing material were starch content and grain yield. Optimum barley genotype was non-waxy naked barley that had low protein, ${\beta}$-glucan, husk content, and high starch content and grain yield.

• Journal of Microbiology and Biotechnology
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• v.11 no.3
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• pp.384-388
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• 2001

The metabolic pathway synthesis algorithm was applied to estimate the maximum ethanol yield from xylose in a model recombinant Saccharomyces cerevisiae strain containing the genes involved in xylose metabolism. The stoichiometrically independent pathways were identified by constructing a biochemical reaction network for conversion of xylose to ethanol in the recombinant S. cerevisiae. Two independent pathways were obtained in xylose-assimilating recombinant S. cerevisiae as opposed to six independent pathways for conversion of glucose to ethanol. The maximum ethanol yield from xylose was estimated to be 0.46 g/g, which was lower than the known value of 0.51 g/g for glucose-fermenting and wild-type xylose-fermenting yeasts.

• Journal of Ginseng Research
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• v.4 no.1
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• pp.1-7
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• 1980

In order to establish effective extracting method of ginseng extracts from fresh ginseng, the yield, chemical composition, physical properties and organoleptic quality of the extracts, which are extracted with various concentrations of ethanol, were investigated. The results are as follows : 1. The yield of the extracts was increased with decreasing the concentration of ethanol as solvent. As in case of water as a solvents, the highest yield was achieved when 23.64% of water was used. The yield were 12.3% and 9.05%, when 70% and 90% of ethanol were used, respectively lively. 2. Crude protein content is the highest level and nitrogen·free extracts content is the lowest at the concentration of 50% ethanol. Lipid was increased linerly while ash was decreased as increment of ethanol concentration. 3. Viscosity and residue of the extracts also decreased in accordance with the increament of ethanol concentration and the transmittance value and pH of extract solutions were almost similar except transmittance value of the water extracts. 4. The extracts extracted with 70% ethanol gave the best result of sensory test. The total sensory test score of each extracts (70%, 90%, 50%, 0% and 30%) were 70, 65, 50, 46 and 41, respectively.

• Transactions of the Korean hydrogen and new energy society
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• v.28 no.6
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• pp.697-703
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• 2017

This study investigated the high-efficient process for bioethanol from barley by various condition. First, higher concentrations of ethanol could be produced without loss of yield by using reducing water consumption. This is because it could prevent to increase viscosity despite reducing water consumption. Second, the ethanol yield could be improved by using reducing particle size of biomass (increase of enzyme reactive surface). Third, The addition of protease could have a considerable effect on yield of fermentation, which provides nutrients to the yeast. This results showed that bioethanol production would provide efficient ethanol production and lower production costs.

• Food Science and Preservation
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• v.30 no.5
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• pp.857-867
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• 2023

In this study, the extraction yield, acidic polysaccharides and ginsenosides of red and black ginseng were optimized by using the response surface methodology in consideration of the ethanol concentration and temperature of the extraction. The R² of the model formula for the yield, acidic polysaccharides and ginsenosides was 0.8378-0.9679 (p<0.1). An optimal extraction yield of 5.29% was reached for red ginseng soluble solids when 1.52% ethanol concentration was used at a temperature of 67.27℃. Additionally, the optimal extraction yield for black ginseng soluble solid was 6.11% when 3.12% ethanol concentration was used at a temperature of 66.13℃. Furthermore, the optimal conditions for extracting acidic polysaccharides from red ginseng were using an ethanol concentration of 4.03% at a temperature of 69.61℃; a yield of 1.86 mg/mL was obtained. The optimal extraction yield for acidic polysaccharides from black ginseng was 1.80 mg/mL when extracted using a concentration of 24.67% of ethanol at a temperature of 71.14℃. An optimal extraction yield of 0.22 mg/mL was reached for ginsenoside Rg₁ from red ginseng when 79.92% ethanol concentration was used at a temperature of 70.62℃. The optimal extraction yield of ginsenoside Rg₃ from black ginseng was 0.31 mg/mL when ethanol was used at a concentration of 75.70% at a temperature of 65.49℃. The ideal extraction conditions for obtaining the maximum yield of both acidic polysaccharide and ginsenoside from red and black ginseng were using ethanol at a concentration between 35 and 50% at an extraction temperature of 70℃.

• Journal of Forest and Environmental Science
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• v.29 no.2
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• pp.125-130
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• 2013

An attempt was made on pulp production from the fast growing plant, Acacia hybrid to determine the total yield, screened yield, Kappa number, and fibre morphology of organosolv Acacia hybrid pulp. Uniform-sized chips were taken to undergo pulping in a digester with five different concentrations of ethanol, 50%, 60%, 70%, 80% and 90% (v/v) with 1 M of sodium hydroxide as catalyst. All chips were digested in a temperature-controlled digester with constant amount of water added and temperature of $185^{\circ}C$ with the duration of three hours cooking time and correspond pressure 1.1-1.2 MPa. It was observed that increasing of ethanol concentration has led to pulp yield increment and decreased in the degree of delignification at the same time. This study was aimed to focus on the effect of the varied concentration of organic solvent towards the pulp yield and its relationship with Kappa number and pulp yield.

• KSBB Journal
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• v.9 no.4
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• pp.395-399
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• 1994

P. stipitis CBS5776 was cultivated to examine the characteristics of ethanol fermentation for hexoses (mannose, g1ucose, and galactose) and pentoses(xylose and arabinose). Glucose was the best carbon source among the sugars used in terms of ethanol yield. Glucose was used to produce ethanol with an yield coefficient 0.376g ethanol/g glucose, whereas mannose was converted to produce ethanol with an yield coefficient 0.326g ethanol/g mannose. P. stipitis CBS5776 was also grown in a mixture of sugars to study the pattern of carbon utilization. The yeast utilized glucose and mannose firsts and then galastose and xylose as carbon sources. Arabinose was partially used for biomass when it was present as a sole carbon source, but it was not metabolized at all in a mixture of carbon sources. P. stipitis produced $12.2g/\ell$ ethanol with a yield coefficient 0.332 g ethano1/g sugar in a mixture of sugars.

• KSBB Journal
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• v.10 no.4
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• pp.370-373
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• 1995

The major by-products in ethanol fermentation by Saccharomyces cerevisiae were glycerol, acetaldehyde, acetic acid, lactic acid, and formic acid. The effects of these by-products on the cell growth and ethanol production were studied. By adding acetaldehyde or acetic acid in the fermentation broth, the cell growth decreased while the ethanol production increased. But glycerol and lactic acid had nearly no effects on the cell growth and the ethanol production. Acetic acid and acetaldehyde inhibited the cell growth by diminishing the growth rate as well as by prolonging the lag phase. The ethanol yield increased with the elevation of concentrations of acetic acid and acetaldehyde in the fermentation broth. The maximum ethanol yield was obtained for $3g/\ell$ acetic acid and $2g/\ell$ acetaldehyde, respectively.

• Microbiology and Biotechnology Letters
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• v.11 no.3
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• pp.181-185
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• 1983

The possibility of the ethanol fermentation from raw cassava starch without cooking was investigated. Saccharification yield in the simultaneous saccharification-fermentation (SSF) system was compared with that in saccharification of raw cassava starch, using glucoamylase of Aspergillus shirousmi. Although the saccharification yield of raw cassava starch with 10 folds of the enzyme was 60% compared to cooked cassava starch, higher saccharification could be obtained by SSF This result is maybe due to the elimination of end product inhibition in saccharification of raw starch by glucoamylase. Final ethanol yield from raw cassava starch was about 88% under the condition of 3$0^{\circ}C$, 120 rpm shaking after 3 days in the SSF system.