• Weed & Turfgrass Science
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• v.2 no.2
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• pp.176-183
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• 2013

To explore hydrolysis methods for the efficient manufacture of sugar solutions from the freshwater alga Water-net (Hydrodictyon reticulatum, HR), acid hydrolysis, enzymatic hydrolysis, and combined hydrolysis (acid followed by enzymatic hydrolysis) were investigated. In the one-step acid hydrolysis, the reaction of 8% solids content using 2% sulfuric acid at $120^{\circ}C$ for 1 hour was desirable. In this case, glucose 27.44 g 100 g $DM^{-1}$ could be obtained from the HR-d13 samples. In the two-step acid hydrolysis, the primary hydrolysis (HR powder : 72% sulfuric acid = 1 g : 1.5 mL) was carried out for 1 hour at $60^{\circ}C$, and then the secondary hydrolysis was done for 1 hour at $120^{\circ}C$ after addition of distilled water 23.5 mL. In this case, glucose 35.11 g/100 g DM could be obtained from the HR-d13 samples. In the combined hydrolysis, 25% solids content using 2% hydrochloric acid were reacted for 1 hour at $120^{\circ}C$, and then citrate buffer and hydrolysis enzyme complexes (E1 1.0 mL+E2 0.2 mL $g^{-1}$ dried matter) were added and reacted for 1 - 2 days at $50^{\circ}C$. In this case, glucose 33.5 g 100 g $DM^{-1}$ could be obtained from the HR-d23+26 samples. In conclusion, combined hydrolysis was likely to be more useful saccharification method of HR biomass at a practical level, considering the glucose productivity, generation of fermentation-inhibiting substances (hydroxyl methyl furfural, furfural), and limited use of strong acid.

• Journal of Korea Foresty Energy
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• v.20 no.2
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• pp.20-27
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• 2001

An effective method for production of glucose was developed using enzymatic hydrolysis of Suwon poplar by the cellulase. Enzymatic hydrolysis of wood is the reaction to produce glucose from wood using enzyme which derives from microorganism. Glucose can be transferred easily to ethanol by fermentation. Ethanol is the starting material for producing acetone, butanol, citric acid and lactic acid. The mechanism of the enzymatic hydrolysis of cellulose are reasonably explained in terms of the sequential action of three different types of enzymes, endo-cellulase, ex-cellulase, and $\beta$ -glucosidase. The goal of this work was to investigate the cellulose hydrolysis pretreated polar with various concentration NaOH, the crystallinity of cellulose, lignin contents and the degree of hydrolysis.

• YAKHAK HOEJI
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• v.35 no.2
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• pp.131-134
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• 1991

A new method for the synthesis of butibufen, which is a non steroidal anti-iriflammatory agent, is described. Friedel-Crafts reaction of isobutylbenzene with ethyl $\alpha$-chloro-.alpha.-(methylthio) acetate (1) gives ethyl $\alpha$-methylthio-(p-isobutylphenyl)acetate (2). Ethyl 2-methylthio-2-(4-isobutylphenyl)butyrate (3) is obtained from treatment of the compound (2) with NaH and Etl. Butibufen (5) is synthesized by reductive desulfurization of the compound (3) with zinc dust-acetic acid or Raney nickel, followed by hydrolysis of the resultant ethyl 2-(4-isobutylphenyl)butyrate (4).

• YAKHAK HOEJI
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• v.33 no.4
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• pp.237-240
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• 1989

A new synthetic method for tiaprofenic acid, which is a potent anti-inflammatory agent, was described. Friedel-Crafts reaction of thiophene with ethyl ${\alpha}-chloro-{\alpha}-(methylthio)$ acetate (1) gave ethyl ${\alpha}-methylthio-2-thiopheneacetate$ (3). Ethyl ${\alpha}-methyl-2-thiopheneacetate$ (5) was prepared by treatment of (3) with NaH and MeI, followed by desulfurization with zinc dust-acetic acid of the resultant ethyl ${\alpha}-methyl-{\alpha}-methylthio-2-thiopheneacetate$ (4). Tiaprofenic acid (7) could be easily synthesized by benzoylation of (5) and hydrolysis of the resultant ethyl $5-benzoyl-{\alpha}-methyl-2-thiopheneacetate$ (6).

• Archives of Pharmacal Research
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• v.16 no.4
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• pp.322-326
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• 1993

For the development of new antinflammatory and analgesic drugs, new 5-alkylthio (or sulfonyl) methyl-5-m-methoxyphenylhydantoin-3-acetic acid derivatives(alkyl; ethyl, propyl, butyl) were prepared. The 5,5 -disubstituted hydantoins which were used as starting materials, were prepared acording to Bucherer-Berg method. The reaction of ethyl chloroacelate with these compounds gave 3-acetate and the subsequent hydrolysis with dilute sodium hydroxide resulted in hydantoin 3-acetate and the subsequent hydrolysis with dilute sodium hydroxide resulted in hydantoin 3-acetic acid derivatives. Through the same procedure of equivalent hydroxide resulted in hydantoin 3-acetic acid derivatives. Through the same procedure of equivelent hydantions or the oxidation of 5-alkylthiohydantoin ocmpounds described above, 5-alkylsulfonylme-thyl-5-m-methoxyphenylhydantoin-30acetic acid derivatives were also synthesized.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2001.06a
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• pp.162-177
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• 2001

The hydrolysis rates of seven kinds of polyol ester base oils 〔POEs〕 of different branch shape were investigated by using a simple apparatus under mild acidic condition. Seven polyol ester base oils were made of poly hydric alcohols of two-four valence, normal or branched fatty acids of different carbon number. p-Toluene sulfonic acid was used as acid catalyst to accelerate the rate of hydrolysis. Partial esters and fatty acid produced by sequential hydrolysis of POEs were identified and their concentrations were determined by calibrated-internal standard method using Gas Chromatography. The rate constants of each step in sequential hydrolysis were determined by the least square method from rate equation and the concentration of each component, were compared with one another. It was shown that the rate of hydrolysis of POEs was strongly affected by whether molecular structure of fatty acid was straight chain or branch chain and which position was branched. The hydrolysis stability for all the POEs can be reasonably explained by using a steric hindrance effect anticipated fi:om their molecular structures affecting as water molecule makes an attack on the carbonyl carbon of POEs.

• Journal of Energy Engineering
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• v.23 no.3
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• pp.241-246
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• 2014

This study is to compare characteristics of saccharification reactions applying to enzymatic hydrolysis of pretreated fallen leaves for bio-ethanol production. It experimented pretreatment of acid, alkaline in the chemical. This experiment includes preteatment of acid and alkaline in chemical, soaking, shaking and autoclaving method, which were applied to biomass. In result, the glucose production from alkaline-NaOH method was 263 mg glucose/ g biomass comparing with them of acid-HCl method. Thus, alkaline-NaOH method is superior than the acid-HCl method for chemical preteatment of fallen leaves. Also, when various chemical treatments were compared, they were all. Based on the results of this study, we found that leaves, one of biomass, are possible in pretreatment and enzymatic hydrolysis process, and they are likely to affect bio-ethanol production in the future.

• Journal of the Korean Society of Food Culture
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• v.24 no.1
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• pp.84-89
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• 2009

This paper was conducted to evaluate aglycones and carbohydrates produced by acid hydrolysis of three potato glycoalkaloids [(PGA); ${\alpha}$-chaconine, ${\alpha}$-solanine, and demissine] in potatoes. Standard solanidine and demissidine were dissolved in 1N HCl and then heated at $100^{\circ}C$ for 10-120 min. Solanidine was rapidly decomposed during acid hydrolysis and one peak that was identified as solantherene ($M^+$=379) by GC-MS was detected. The transformation solanidine to solanthrene was approximately 50% complete after 10 min, approximately 90% complete after 60 min and 100% complete after 120 min. Demissidine was hydrolyzed using the same method that was used to hydrolyze the solanidine. However, demissidine produced only one peak upon GC-MS ($M^+$=399) analysis and was found to be very stable at increased temperatures. Acidy hydrolysis of ${\alpha}$-chaconine, ${\alpha}$-solanine and demissine resulted in the decomposition of ${\alpha}$-chaconine and ${\alpha}$-solanine to solanidine and solanthrene, respectively. Therefore, this hydrolysis method should not be utilized to produce PGA combining with solanidine as aglycone. The individual carbohydrates produced by the two PGAs by hydrolysis were very stable at increased temperatures; therefore, it was possible to quantify these PGAs based on calculation of the individual carbohydrate content. Conversely, because demissidine produced by the hydrolysis of demissine was extremely stable at increased temperatures, it was possible to quantify the PGA based on the aglycone produced by hydrolysis.

• Biotechnology and Bioprocess Engineering:BBE
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• v.5 no.3
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• pp.196-201
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• 2000

Lactic acid is of interest as the raw materials of polyactide that is a biodegradable polymer. For an effective purification of acid, batch distillation with the simultaneous reactions was used. Two Oldershow colums and reboilers were usde for fractionation of methanol and reactions. Two Oldershaw columns and reboilers were used for fractionation of methanol and reactions. Esterification reaction of lactic with methanol produced methyllactate and water. The productes of the esterification reaction, methl lactate and water were transported to the reboiler of the reproysis part. In hydroduced in the hydrolysis part and nureacter method lactic acid and methanol. Methanol produced in the hydroysis part and unreacted method lactic acid and methanol in the esterification part were separated by distillation and recycled to the revoiler of the esterification part so that the esterification reaction would be stimulated. Thus, pure lactic acid solution remained in the reboiler of the hydroysis part. The effect of the number of stages in column on the recovery yield was also inverstigated. In the operation with colums improved the fractionation of componets and stimulated the reactions in two parts.

• Microbiology and Biotechnology Letters
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• v.1 no.1
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• pp.31-36
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• 1973

A method for acid-hydrolysis of agricultural wastes and its utilization was investigated. In order to obtain fermentable sugar solution from cellulosic wastes such as cereal straws and hulls, in particular, of rice, barley and wheat, the chemical compositions were analyzed and optimum conditions of hydrolysis determined. The cereal straws contain 42 to 55 % of crude cellulose including hemicellulose. On the hydrolysis with 1% of sulfuric acid at 40 psig, 35.6% of the reducing sugar based on the weight of dry matter was formed from rice straw, (variety Chinheung) in 30 min. More powerful condition of hydrolysis would appear to decompose the sugar formed into other compounds, for instance, furfural. Under atmospheric pressure with 5% of the acid, rice straw was hydrolyzed to 35% of reducing sugar content in 3 hours. Candida utilis could assimilate the sugars in the hydrolyzate up to more than 97%, and a yield of the yeast cells reached 55% to the utilized sugars.