• KSBB Journal
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• v.6 no.3
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• pp.263-270
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• 1991

The optimal cell concentration and dilution rate for maximum ethanol productivity were obtained using dynamic simulation in cell recycled continuous bioreactor. The good control performance was observed using rule-based STR (self-tuning regulator) compared to conventional STR. Rule-base contained the scheme to implement the STR in an efficient on-off way and the scheme for the controlled variable to reach the optimal value in a short time. Since a mathematical model was used to analyze and estimate the changes of the state variables and the parameters, it was possible to understand the physical meaning of the system.

• Bulletin of Food Technology
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• v.23 no.2
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• pp.220-223
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• 2010

최근에 대두되고 있는 환경오염문제라던가 원유의 의존도 측면에서 볼 때 삼림자원 바이오매스를 원료로 한 bioethanol의 중요성이 높아지고 있다. 현재 bioethanol 제조는 효모 등을 이용한 발효법으로 대부분 제조되고 있지만 효소를 이용한 bioethanol 제조를 할 수 있다면 효율이 높은 ethanol생산과 이 반응에서 나오는 반응산물을 간단하게 정제할 수가 있게 된다. 또한 내열성 효소를 이용하여 고온 조건에서 효소반응을 하게 되면 효소반응과 반응산물 증류를 동시에 진행할 수 있으며, 반응속도의 향상과 잡균의 혼입억제 등 여러가지 이점이 기대된다. 본 고에서는 내열성 효소를 이용한 cellulose와 hemicellulose로부터 ethanol 제조 연구에 대한 개요를 살펴보기로 한다.

• KSBB Journal
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• v.14 no.1
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• pp.24-30
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• 1999

The fed-bach simultaneous saccharification and fermentation (SSF) of newspaper to ethanol with Brettanomyces custersii was studied. The initial substrate concentration for the effective fed-batch SSF was 8% (w/v). The initial optimum enzyme concentration was 30 FPU/g cellulose for cellulase and the optimum volumetric ratio of $\beta$-glucosidase to cellulase was 0.1. When 4% (w/v) of ball-milled newspaper was supplemented intermittently at time intervals, considering the mixing of newspaper slurry, the fed-batch SSF showed higher ethanol concentration (26.80 g/L) and two times higher ethanol production yield based on enzyme than the batch SSF.

• Microbiology and Biotechnology Letters
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• v.16 no.3
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• pp.205-212
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• 1988

The immobilized cell tubular tormentor was prepared by wood chips or alginate gel. Investigations of characterization of the performance of ethanol fermentation in the immobilized cell tubular tormentor were undertaken and the results were compared with those of other tormentors. The immobilized cell tormentor packed with alginate gel showed much higher ethanol productivity than that with wood chip. It was concluded that the immobilized cell tubular tormentor packed with alginate gel might offer better perspectives for continuous ethanol production than that with wood chip.

• Journal of Forest and Environmental Science
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• v.36 no.1
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• pp.62-66
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• 2020

Ethanol fermentation of the enzymatic hydrolysates from the products pretreated using 1-ethyl-3-methyl-imidazolium acetate ([EMIM]Ac) and its co-solvents with dimethylformamide (DMF) was conducted using Saccharomyces cerevisiae (D452-2). The optical density change due to the yeast cell growth, the consumption amount of monosugars (glucose, xylose), the concentration of acetate, and ethanol production yield were investigated. The co-solvent system lowered inhibition of the growth of the cells. The highest concentration of glucose (7.8 g/L) and xylose (3.6 g/L) was obtained from the enzymatic hydrolysates of the pretreated product by pure [EMIM]Ac. The initial concentration of both monosugars in the enzymatic hydrolysates was decreased with increasing fermentation time. Ethanol of Approximately 3 g/L was produced from the enzymatic hydrolysates by pure [EMIM]Ac and co-solvent with less than 50% DMF.

• The Korean Journal of Food And Nutrition
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• v.13 no.2
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• pp.152-157
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• 2000

In order to select the optimum drying method for the production of cinnamon extract, water extract and 70% ethanol extract of cinnamon were prepared. And then several drying method of oven drying, vacuum evaporation, spray drying and freeze drying were performed. Content of cinnamic acid, cinnamic aldehyde, eugenol, tannin and free sugar, and antioxidant activity, degree of browning, pH, color value, turbity and solubility were compared. In water extract, contents of cinnamic acid, cinnamic aldehyde, eugenol were 29.45mg/100g, 94.86mg/100g, 120.75mg/100g and decreased to 4.76%∼44.21%, 5.30%∼48.05%, 3.66%∼21.83% by oven dyring, vaccum drying, spray drying respectively, but freeze drying showed a little decrease of those components. In 70% ethanol extract, effectual components decreased to 76.05%∼88.38% and 26.86%∼78.76% by freeze drying and vacuum evaporation respectively. Antioxidant activity decreased by drying and decreasing rate in 70% ethanol extract was lower than water extract. Degree of browning increased as the drying temperature increased. Tannin and free sugars were little affected by drying temperature. Solubility decreased in oven drying and 70% ethanol extract. Overall data suggested that optimum drying methods of cinnamon extract were freeze drying in case of water extract and freeze drying and vaccum drying in case of 70% ethanol extract.

• Textile Coloration and Finishing
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• v.25 no.4
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• pp.327-336
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• 2013

The purpose of this study was to evaluate the color image of the natural-dyed silk fabrics. The dye was extracted from pine needle by boiling pine needle with ethanol at $78^{\circ}C$ for 3hours and distilled water at $100^{\circ}C$ for 2hours. The 100% silk fabric was dyed of extract in pH 5 at $90-100^{\circ}C$ for 1 hr. As mordants used were compounds of Al, Sn, Fe, and Cr, color image of pine-needle dyed silk fabrics was classified into 5 factors (pure, gentle, sophisticate, comfortable, pastorale) and the factor pure is most important one of those. Most cheerful image in pure factor was from the fabrics dyed with ethanol extract and then, none and Cr mordanting. Dignified image was from the fabrics dyed with ethanol extract and then, Cu or Fe mordanting. In production, products dyed with ethanol extracts was preferred to those dyed with distilled water extracts. Color image and preference of the silk fabrics dyed with pine needles extracted was affected by extraction solvents and mordants.

• KSBB Journal
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• v.7 no.1
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• pp.27-31
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• 1992

Xylose represents a major component of cellulosic materials. This paper describes patterns of ethanol fermentation by Saccharomyces cerevisiae from xylulose, which is an isomer of xylose. Special emphasis was placed on the effects of xylulose concentration and growth temperature on cell growth and ethanol yield. The maximum specific growth of $0.087 1/hr^{-1}$ was obtained at an initial xylulose concentration of 5 g/1. The ethanol yield was propotional to initial xylulose concentrations. A xylulose concentration of 16 g/l resulted in the maximum ethanol yield of 0.49 g EtOH/g xylulose, which corresponds to 90% of a theoretical value. It is interesting to nota that xylulose metabolism was accelerated by the presence of glucose as a carbon source.

• Biomedical Science Letters
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• v.27 no.3
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• pp.161-169
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• 2021

The present study, antioxidant and anti-inflammatory effects were measured of 6 endemic plants in Indonesian extracted by hot water or ethanol. The Nipa Fruticans Wurmb ethanol extract (NFWE) and Orthosiphon aristatus ethanol extract (OAE) showed the highest polyphenol and flavonoid contents of 203.70 and 33.70 ㎍/mg, respectively. Antioxidant activity of OAE was highest in DPPH radical scavenging activity (77.49% at 10 ㎍/mL) and ABTS⁺ radical scavenging activity (93.36% at 10 ㎍/mL). FRAP activity was significantly higher in NFWE than other extracts. Anti-inflammatory effects of 6 endemic plants in Indonesian extracted by hot water or ethanol were examined using nitric oxide (NO) inhibition assays. In the LPS-induced BV2 cells, OAE showed the highest inhibition of NO production without toxicity. The results of this study, suggest that OAE is a potential functional raw material for antioxidant and anti-inflammatory.

• Korean Chemical Engineering Research
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• v.59 no.3
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• pp.467-479
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• 2021

Abstract: A kinetic model was developed for the dehydration of ethanol to ethylene based on two parallel reaction pathways. Kinetic parameters were estimated by fitting experimental data of powder catalysts in a lab-scale test, and the effectiveness factor was determined using data from pellet-type catalysts in bench-scale experiments. The developed model was used to design a multitubular fixed-bed reactor (MTR) and an adiabatic reactor (AR) at a 10 ton per day scale. The two different reactor types resulted in different process configurations: the MTR consumed the ethanol completely and did not produce the reaction intermediate, diethyl ether (DEE), resulting in simple separation trains at the expense of high equipment cost for the reactor, whereas the AR required azeotropic distillation and cryogenic distillation to recycle the unreacted ethanol and to separate the undesired DEE, respectively. Quantitative analysis based on the equipment and annual energy costs showed that, despite high equipment cost of the reactor, the MTR process had the advantages of high productivity and simple separation trains, whereas the use of additional separation trains in the AR process increased both the total equipment cost and the annual energy cost per unit production rate.