• Journal of Marine Bioscience and Biotechnology
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• v.1 no.4
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• pp.311-316
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• 2006

Enzymatic ethanolysis of fish oil with immobilized lipase was investigated for reducing the free fatty acid contents and enhancing the function of fish oil. Ethanolysis reactions were carried out in erlenmeyer flask (25ml) containing a mixture of squid viscera oil and 99.9% ethanol using 1% (based on w/w squid viscera oil) immobilized lipase. The reaction mixtures were incubated at $50^{\circ}C$ and shaken at 100rpm. Ethanol was added into the mixture by stepwise addition method of Shinmada[9]. Measurement of free fatty acid molar amounts was studied by Acid Value. Tendency of oil variation during transesterification was studied by TLC method. Enzymatic ethanolysis composed diglyceride, monoglyceride and fatty acid ethyl ester with reducing free fatty acid contents. Also, selective ethanolysis by Lipozyme TL-IM and Lipozyme RM-IM mostly did not react at the sn-2 position of squid viscera oil. Lipozyme RM-IM was more suitable enzyme to reduce the free fatty acid contents by ethanolysis than Lipozyme TL-IM. Squid viscera oil was transformed into suitable properties (5 in Acid Value) for functional fish oil production.

• 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.

• Microbiology and Biotechnology Letters
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• v.20 no.1
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• pp.73-78
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• 1992

- Enzymatic synthesis of L-tryptophan(Trp) using E. coli tryptophanase has been investigated. In order to reduce the substrate inhibition by indole and to increase the product yield of L-tryptophan three different approaches have been made in this work. First, indole was intermittently fed to the reaction mixture in order to control the indole concentration at lower level. When 15 mM of indole was used as a total amount of substrate, conversion yield of 80% has been obtained with intermittent feeding while only 20% of indole was converted into L-tryptophan by conventional batch operation, The second method employed in this work was the use of cyclohexane-phosphate buffer organic two-phase system. In this system, indole was mainly partitioned into the organic-solvent phase and therefore substrate inhibition was expected to be reduced. L-Tryptophan production in organic two-phase system was, however, unexpectedly lower than that obtained in aqueous buffer solution. As a third method cyclodextrins have been added to the aqueous reaction mixture. It was found that the addition of $\beta$-cyclodextrin enhanced the tryptophan synthesis noticeably while $\alpha$-cycfodextrin showed little effect on tryptophan production.

• KSBB Journal
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• v.18 no.5
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• pp.363-370
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• 2003

A filamentous fungus, strain FM04 producing amylase was isolated from rotten yam peels and potatoes. The favorable conditions of cultivation factors such as, temperature, pH, and agitation speed of strain FM04 were 28∼30$^{\circ}C$, 5.0∼6.0, and 100 rpm, respectively. Starch was the best carbon source in the amylase production. Therefore, food wastes containing lots of starch were employed as the carbon source of the cultivation for the economical amylase production. 5.2 U/ml of amylase was obtained In the cultivation using 1 % (w/v) of food wastes. The amylase showed the highest activity at enzyme reaction conditions of 60$^{\circ}C$ and pH 4.5 and showed 90% of residual activity after the reaction at 50$^{\circ}C$ for 2 days. In the enzymatic hydrolysis reaction using 20% (w/v) of food wastes and 2.5 U/ml of amylase, 72.6 g/l of reducing sugar was obtained at the reaction condition of 50$^{\circ}C$, pH 4.5 for 2 days.

• Korean Chemical Engineering Research
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• v.53 no.4
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• pp.417-424
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• 2015

In this study, the pretreatment of Helianthus tuberosus residue had been performed. The two-stage pretreatment on flow-through process were applied in the interests of increase of sugar production yield on enzymatic saccharification. The delignification by aqueous ammonia and the fractionation of hemicellulose by sulfuric acid solution as pretreatment solution were confirmed for effects of enzymatic saccharification. Two-stage pretreatment process was performed using aqueous ammonia and sulfuric acid. The first step was performed with aqueous ammonia for 40 min at $163.2^{\circ}C$ and the second step was performed with sulfuric acid solution for 20 min at $169.7^{\circ}C$. And then, the first step was performed with sulfuric acid solution and the second step was pretreated with aqueous ammonia. At this time, the glucose production was 30.7 g and the glucose yield was 72.4% in the first step process with aqueous ammonia. And, the glucose production was 20.9 g and the glucose yield was 49.3% in the first step process with sulfuric acid solution.

• KSBB Journal
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• v.28 no.2
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• pp.65-73
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• 2013

This study aimed to investigate the enzymatic hydrolysis of mannitol using Viscozyme$^{(R)}$ L, Celluclast$^{(R)}$ 1.5 L, Saczyme$^{(R)}$, Novozym$^{(R)}$, Fungamyl$^{(R)}$ 800 L, Driselase$^{(R)}$ Basidiomycetes sp., and Alginate Lyase, and to optimize of reaction conditions for production of reducing sugar. Response surface methodology (RSM) based on central composite rotatable design was used to study effects of the independent variables such as enzyme (1-9% v/w), reaction time (10-30 h), pH (3.0-7.0) and reaction temperature ($30-70^{\circ}C$) on production of reducing sugar from mannitol. The coefficient of determination ($R^2$) of $Y_1$ (yield of reducing sugar by Viscozyme$^{(R)}$ L) and $Y_3$ (yield of reducing sugar by Saczyme$^{(R)}$) for the dependent variable regression equation was analyzed as 0.985 and 0.814. And the p-value of $Y_1$ and $Y_3$ showing 0.000 and 0.001 within 1% (p < 0.01), respectively, was very significant. The optimum conditions for production of reducing sugar with Viscozyme$^{(R)}$ L were 9.0 % (v/w) amount of enzyme, 30.0 hours of reaction time, pH 4.5 and $30.0^{\circ}C$ of reaction temperature, and those with Saczyme$^{(R)}$ were 9.0% (v/w) of amount of enzyme dosage, 30.0 h of reaction time, pH 7.0 and $30.0^{\circ}C$ of reaction temperature, consequently, the predicted reducing sugar yields were 22.5 and 27.9 mg/g-mannitol, respectively.

• Journal of Forest and Environmental Science
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• v.27 no.3
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• pp.143-149
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• 2011

The possibility of employing biomass of Salix viminalis cv. Q683 as a resource of bio-energy was evaluated. The chemical analysis of S. viminalis cv. Q683 leaf biomass showed components such as, extractives (2.57%), lignin (39.06%), hemicellulose (21.61%), and cellulose (37.83%), whereas, its stem was composed of extractives (1.67%), lignin (23.54%), hemicellulose (33.64%), and cellulose (42.03%). The biomass of S. viminalis cv. Q683 was saccharified using two enzymes celluclast and viscozyme. The saccharification of S. viminalis cv. Q683 biomass was influenced by enzymes and their strengths. The optimal enzyme combination was found to be celluclast (59 FPU/g substrate) and viscozyme (24 FBG/g substrate). On saccharification the glucose from leaf and stem biomass was 7.5g/L and 11.7g/L, respectively after 72 hr of enzyme treatment. The biomass and enzyme-treated biomass served as the feedstock for ethanol production by fermentation. The ethanol production from stem and leaf biomass was 5.8 g/L and 2.2 g/L respectively, while the fermentation of the enzymatic hydrolysates yielded 5 g/L to 8 g/L bioethanol in 72 hours.

• Journal of Life Science
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• v.26 no.12
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• pp.1477-1486
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• 2016

Lactulose (4-O-${\beta}$-D-galactopyranosyl-D-fructose) is a non-digestible synthetic ketose disaccharide which can used in food and pharmaceutical fields due to its useful functions for encephalopathy, chronic constipation, hyperammonemia, etc. Therefore, the lactulose is regarded as one of the most important disaccharides and have been concentrated much interesting as an attractive functional material in the current industry. From this reason, the research related on the production of lactulose has been carried out various academic and industrial research groups. To produce lactulose, two main methods, chemical production and enzymatic production have been used. Commercially lactulose produced by alkaline isomerization of lactose as chemical production method but it has many disadvantages such as rapid lactulose degradation, purification, and waste management. From these reasons, lactulose produced by enzymatic method which solves these problems has been suggested as a proper method for lactulose production. Two different enzymatic methods have been reported as methods for lactulose production. Lactulose can be obtained through hydrolysis and transfer reaction catalyzed by a ${\beta}$-galactosidase which requires fructose as co-substrate and exhibits a low conversion. Alternatively, lactulose can be produced by direct isomerization of lactose to lactulose catalyzed by cellobiose 2-epimerase which requires lactose as a single substrate and achieves a high lactulose yield. This review summarizes the current state of lactulose production by chemical and biological methods.

• Preventive Nutrition and Food Science
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• v.14 no.1
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• pp.21-28
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• 2009

In this study, we focused on natural water-soluble antioxidants from Tetraselmis suecica (T. suecica) and Chlorella ellipsoidea (C. ellipsoidea). They were prepared by enzymatic digestion using five carbohydrases (Viscozyme, Celluclast, AMG, Termamyl and Ultraflo) and five proteases (Protamex, Alcalase, Flavourzyme, Neutrase, and Kojizyme), and the potential antioxidant activity of each was assessed. Most enzymatic digests from T. suecica had a higher radical scavenging activity than those from C. ellipsoidea. Among the enzymatic digests, Kojizyme digest from T. suecica exhibited the highest effect on DPPH radical scavenging. Viscozyme (30.2%) and Neutrase (34.6%) digests from T. suecica exhibited higher hydroxyl radical scavenging activity. Kojizyme digest from T. suecica (81.5%) had strong alkyl radical scavenging activity. Neutrase (61.9%) and Kojizyme (61.5%) digest from T. suecica possessed the highest effects on hydrogen peroxide scavenging. Among the tested samples, Neutrase (TN) and Kojizyme (TK) digests from T. suecica showed the highest antioxidant activity (DPPH, alkyl radical, hydrogen peroxide). Therefore, TN and TK digests were selected for use in the further experiments. Those digests showed enhanced cell viability against $H_2O_2$-induced oxidative damage, and relatively good hydrogen peroxide scavenging activity in an African green monkey kidney (Vero) cell line. These results suggested that an enzymatic digestion will be an effective way for the production of a potential water-soluble antioxidant from a microalgae, T. suecica.

• Journal of the Korean Wood Science and Technology
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• v.48 no.5
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• pp.651-665
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• 2020

Hydrolysis of biomass for the production of fermentable sugar can be improved by the addition of surfactants. In pulp and paper mills, lignin, which is a by-product of the pulping process, can be utilized as a fine chemical. In the hydrolysis process, lignin is one of the major inhibitors of the enzymatic breakdown cellulose into sugar monomer. Therefore, the conversion of lignin into a biosurfactant offers the opportunity to solve the waste problem and improve hydrolysis efficiency. In this study, lignin derivatives, a biosurfactant, was applied to enzymatic hydrolysis of various lignocellulosic biomass. This Biosurfactant can be prepared by reacting lignin with a hydrophilic polymer such as polyethylene glycol diglycidylethers (PEDGE). In this study, the effect of biosurfactants on the enzymatic hydrolysis of pretreated sweet sorghum bagasse (SSB), oil palm empty fruit bunch, and sugarcane trash with different lignin contents was investigated. The results show that lignin derivatives improve the enzymatic hydrolysis of the pretreated biomass with low lignin content, however, it has less influence on the enzymatic hydrolysis of other pretreated biomass with lignin content higher than 10% (w/w). The use of biosurfactant on SSB kraft pulp can increase the sugar yield from 45.57% to 81.49%.