• Journal of the Korean Wood Science and Technology
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• v.32 no.1
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• pp.28-34
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• 2004

This study was performed to evaluate the characteristics of the carboxymethylated substrate from high reactive autohydrolyzed cellulose (HRC) and those of commercial α-cellulose (CAC) and refiner mechanical pulp (RMP). Saccharification rates of HRC substrate were achieved over 70% with 12 hr hydrolysis, about 90% with 24 hr, and 99.5% with 72 hr. CMCase and avicelase activities of cellulase onozuka were 4.09 ㎛ G/mg·min and 14.0 ㎛ G/mg·min, respectively. There were no any significant changes in cellulase activities with this substrate. The saccharification rates of CAC and RMP were very low, 57% and 38% with 72 hr, respectively. Those lignin-zero autohydrolyzed substrates, HRC and CAC, were highly carboxymethylated at the high alkali concentration, near 30%, for 3 hr. reaction, and resulted in 1.13-1.15 of D.S., besides 0.85 of D.S. from RMP. Water solubilities of carboxymethylated substrates were increased with an increase of D.S., 98-98.5% from HRC and CAC and 31.5% from RMP. RMP which has low specific surface area showed lower water retention values, compared to high values of 435 and 321% from CAC and HRC, respectively. There were no direct relationship between surface area and swelling ratio of the substrates.

• Korean Chemical Engineering Research
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• v.51 no.4
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• pp.438-442
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• 2013

The study of bioproduct production from inexpensive biomass such as marine biomass has recently attracted considerable attention. Because, marine biomass which compared to land biomass, it can be grown rapidly and is easily cultivated without the need for expensive equipment. In addition, the carbohydrate contents are similar or higher than land biomass such as woody biomass and can be easily converted to chemicals through proper chemical processes. In the production of various biochemicals from marine biomass, levulinic acid is a highly versatile chemical with numerous industrial uses and has the potential to become a commodity chemical. It can be used as a raw material for resins, plasticizers, textiles, animal feed, coatings and antifreeze. In this study, experiments were carried out to determine the optimum conditions of temperature, acid concentration and reaction time for production of levulinic acid from marine biomass, Gelidium amansii, using two-step treatment. In the first hydrolysis step, solid-state cellulose which was used to produce ethanol by fermentation and liquid-state galactose which used to produce bioproduct such as levulinic aicd were obtained through acid soaking. In the second hydrolysis step, the liquid-state galactose was converted into levulinic acid via a high-temperature reaction in a batch reactor. As a result, the overall production yield of Gelidium amansii to levulinic acid in the two-step acid hydrolysis was approximately 20.6% on the initial biomass basis.

• Fibers and Polymers
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• v.5 no.1
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• pp.44-51
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• 2004

Three bi-functional reactive dyes such as Bis(vinylsulphone) type, Bis(monochlorotriazine) type and Bis(mononicotinotriazine) type were applied to regular viscose rayon and new regenerated cellulosic fiber ($enVix^ⓡ$) which was prepared from cellulose acetate fiber by the hydrolysis of acetyl groups, and their dyeing properties and fastness properties were compared. enVix exhibited better dyeability and fastness than regular viscose rayon and these results were also explained by the differences in the supramolecular structure of these two fibers.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.32 no.1
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• pp.72-78
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• 2000

The major cause of paper deterioration is the acid-catalyzed hydrolysis of the cellulose in paper fibres. The deacidification of paper reduced the rate of this deterioration, and it has been reported to extend the useful life of acidic paper by three to five times. It has been recognized the need for an effective method of deacidifying large quantities of books and documents. T도 review of the current state of deacidification technology has been published recently. The paper points to the immediate need for a cost-effective and reliable method to save the millions of books that prish every year. It was tried to deacidify by the gaseous ethanolamine for solving with the above the problem. Acidic paper was treated with the monoethanolamine, diethanolamine, triehtanolamine. It result, it was found that the rate of deacidification was in caused very little grightness and fold endurances. For solving this problem, it was carried with deacidify by combination treatment of the various gaseous ehtnaloamines. In result, decreasing of brightness and fold endurance is reduced.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 1999.11b
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• pp.149-152
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• 1999

A new process for deinking of colored offset newsprint, i.e. enzyme treatment in cooperation with ultrasonic wave was developed in the present study. The physical characteristics such as fiber length, coarseness, crystallinity index of the deinked pulps were investigated and the sugar residues released from the treatment were analyzed. It was found that colored offset newsprint could be deinked effectively by cellulase treatment when ultrasonic wave was applied. The brightness increased by 5% ISO over that of control experiment and the pigment content was reduced markedly. Though the ultrasonic wave had little effect on the strength and crystallinity of the pulp, the treatment of enzyme combined with ultrasonic wave reduced the coarseness and fiber length to some extent. It was also found that ultrasonic wave could accelerate the hydrolysis of cellulose and hemicellulose during the cellulase treatment.

• Fibers and Polymers
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• v.7 no.3
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• pp.241-244
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• 2006

In this paper, the effect of cellulase treatment was evaluated by means of phenol-sulphuric acid method. This method was performed by determining sugar liberation in the treatment bath with the amount expressed in glucose equivalent. As compared with conventional method, the measurement of amount of sugar liberated gave a more reliable and accurate result than the weight loss method. It was found that although the weight loss of cellulose became negligible when the treatment was done under agitation-free condition, the amount of sugar liberated was still readily measurable.

• Journal of the Korean Ceramic Society
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• v.31 no.1
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• pp.1-10
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• 1994

Monodispersed alumina and Mg-doped alumina fine particles were prepared by controlled hydrolysis of alkoxides. Aluminium alkoxide and magnesium alkoxide were dissolved into complex solvent which was composed of hydrophobic n-octanol and hydrophilic acetonitrile. Hydroxypropyl cellulose(HPC) was used as a dispersant for the alumina particles. The size of these prepared powders was approximately 0.3 ${\mu}{\textrm}{m}$. In the case of sintering above 100$0^{\circ}C$, most of these prepared powders were transformed to $\alpha$-alumina. The relative density of the sintered body of these prepared powders at 1$600^{\circ}C$ was 98%. The sintered body of the Mg-doped alumina powder had more uniform grain size than that of the undoped alumina podwer.

• KSBB Journal
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• v.28 no.2
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• pp.131-136
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• 2013

The hydrolysates prepared with various enzyme digestion of Capsosiphon fulvescens were used to measure the inhibitory effects against angiotensin I converting enzyme (ACE). The commercially available enzymes such as Celluclast, Viscozyme, Lysing enzyme, Flavourzyme, Alcalase and Pectinex were used to digest C. fulvescens and produce hydrolysates. The maximum ACE inhibitory activity was observed using Alcalase hydrolysis (72.9%). The optimal conditions of Alcalase extraction were pH 8.0 and extraction time for 12 hr. The hydrolysates were fractionated using preparative-LC and anion-exchange chromatography on DEAE-cellulose and the fraction B and B-2 were isolated. The ACE inhibitory activity of fraction B-2 by anion-exchange chromatography was 82.6%. The molecular weight of fraction B-2 estimated using size exclusion chromatography was about 1 kDa. The monosaccharide composition of the fraction B-2 was determined to be mannose (1.1%), glucuronic acid (1.3%), galactose (1.3%) and glucose (96.3%).

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.43 no.1
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• pp.29-35
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• 2011

Since the role of lignin in the wood cell wall is to keep integrity and structure rigidity of lignocellulosic substrate, lignin of the cell wall has to be destroyed before enzymatic hydrolysis of wood polysaccharides. The aspen wood meals were delignified with ozone in acidic condition. The chemical characteristics of wood meal were investigated. The 60% of lignin and almost zero % of polysaccharides in aspen wood meal was degraded with 10min. ozone treatment. The phenolic hydroxyl groups of lignin in ozonated wood meal were increased with ozonation time. The sugar composition of ozonated wood meal showed that the hemicellulose was more susceptible to ozonation than cellulose. The yield of aldehyde was increased in some degree with 10min. ozone treatment and decreased with longer ozone treatment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.3
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• pp.255-262
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• 1992

In vitro digestibility of filefish, protein was substantially decreased by fiber constituents in the follow-ing order : pectin (9.97%), gum karaya (7.03%), sodium alginate (6.12%),and cellulose (1.52%). The order of reduction by fibrous residues from vegetables ranked as follows : sea tangle (12.36%), Ro-maine lettuce (11.12%), perillar leaf (8.96%), and green pepper (5.15%). The inhibitory effect of the dietary fibers towards filefish protein digestion, expressed as soybean trypsin inhibitor equivalents, in-creased with added levels, but the inhibition differed with the sources of dietary fibers. Sea tangle and sodium alginate were most active in decreasing the concentration of essential amino acid from filefish protein hydrolysis. Sodium alginate exerted an inhibitory effect on the activity of trypsin, but the other fiber constituents did not have an inhibitory potency on trypsin and bacterial pretense (Streptomyces griceus). Results supported that dietary fiber components may reduce protein digestibility through the interaction of dietary fiber components with filefish protein.