• Journal of Ginseng Research
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• v.34 no.4
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• pp.321-326
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• 2010

Enzymatic treatment conditions for red ginseng residue (RGR) were investigated to apply RGR as a microbial medium. Polysaccharide hydrolyase and protease were screened to obtain high solid and carbohydrate yields, and a good degree of carbohydrate hydrolysis. The optimal dosage and reaction time for Viscozyme, the chosen polysaccharide hydrolyase, were found to be 1.0% (w/w) and 3 h, respectively. Of the tested proteases, Flavourzyme, whose optimal dosage was 0.5% (w/w), was selected. Co-treatment with the optimal dosages of Flavourzyme and Viscozyme increased solid yield, carbohydrate yield, and degree of carbohydrate hydrolysis by 76%, 65%, and 1,865%, respectively, over levels in non-treated RGR. The culture characteristics of Leuconostoc mesenteroides strain KACC 91459P grown in enzymatically hydrolyzed red ginseng residue (ERGR) and RGR suspensions were compared. After cultivation for 6 h, the viable cell counts of both cell suspensions rapidly increased to $1.3{\times}10^9$ colony-forming units (CFU)/g. Moreover, while the viable cell population drastically decreased to $2.4{\times}10^6\;CFU/g$ for cells grown in RGR medium, it was maintained in cells fermented in ERGR medium for 24 h.

• Journal of Life Science
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• v.25 no.7
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• pp.795-800
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• 2015

Oyster is a nutritionally good food ingredient. Also, oyster is used to make source for taste and flavor. This study tried to investigate optimal condition of hydrolysis of oyster and oyster cooking drip for better amino acid content to make good taste and flavor. And then this study characterized hydrolysate of oyster and oyster cooking drip. Enzymes are Acalase, Flavourzyme, Neutrase, and Protamax. The optimal condition for the highest enzyme activity is given by the company. Under the best condition of each enzymes, they react with the homogenized oyster and oyster cooking drip for 0.5, 1.0, 1.5, 2, 4, 6 hr. The degree of oysters’ hydrolysis is 13.2±0.1%. But, in the case of using enzyme, the rate of hydrolysis sharply increased as time went on during 2 hr. After 8 hr, the rate is 36.9~40.5%. Protamax showed 27.4±0.4% of hydrolysis rate in 2 hr. And the degree of oyster cooking drop hydrolysis is 42.7±0.1%. The highest of hydrolysate concentration is 72.1±0.1% using protamax. In the case of oyster, it has a similar tendency of all enzymes. Otherwise, the hydrolysate of oyster cooking drip had a difference among the enzymes. Composition of free amino acid of hydrolysate using protamax was investigated how much time showed highest rate of hydrolysis to find best amino acid composition. Hydrolysis using Protamax during 6 hr is selected for best condition.

• Food Science and Preservation
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• v.13 no.1
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• pp.71-76
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• 2006

We monitored the characteristics of soybean hydrolysate prepared under various hydrolysis condition using response surface methodology. The yield was affected by protease content but 1be effect of hydrolysis time to yield gradually increased at over $0.4\%$ of protease, while the $R^2$ of polynomial equation was 0.978 (p<0.01). The soluble solid enlarged by increase of both variables and the $R^2$ of polynomial equation was 0.954 (p<0.01). The degree of hydrolysis was affected by protease content at low (under $0.4\%$) protease and maximized at $0.57\%$ protease and 5.49 hrs. The $R^2$ of polynomial equation for the degree of hydrolysis was 0.916 (P<0.05). The calcium intolerance capacity showed similar pattern like yield but the effect of hydrolysis time was rapidly increased at over $0.4\%$ protease. The $R^2$ of polynomial equation for calcium intolerance capacity was 0.932 (p<0.05). The total phenolic compounds increased in proportion to protease content and hydrolysis time, while the $R^2$ of polynomial equation was 0.920 (p<0.05). According to the results of this study, the optimal conditions for soybean hydrolysis were predicted to be $0.51\~0.66\%$ of protease and $6.5\~9.0\;hrs$, and the predicted values and actual values of each response variable were similar to each other when the hydrolysis was performed at a random point within the optimal range.

• Proceedings of the Membrane Society of Korea Conference
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• 1996.10a
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• pp.92-93
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• 1996

PVA membrane was widely used in the dehydration pervaporation process. PVA membrane showed remakable selectivity towed water and an excellent film-forming polymer, with a good resistance to orgamic solvents but it has poor stability in aqueous mixtures. Generally the PVA is manufactured by the hydrolysis reaction from poly vinyl acetate(PVAc) and so the degree of PVA hydrolysis is a major parameter for properties of PVA membrane such as the crystallinity and polarity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.6
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• pp.1086-1090
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• 1997

Morphological properties on lintnerized maize starches with different amylose content were investigated. With increasing the lintnerization periods and decreasing the amylose content, hydrolysis rate was increased. As amylose content of starch was increased, the degree of damage with acid treatment was decreased by SEM. With increasing hydrolysis, iodine affinity, apparent amylose content and ${\lambda}_{max}$ of lintnerized starches were decreased. Water binding capacities of lintnerized starches were higher than those of native starches.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.42 no.3
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• pp.67-73
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• 2010

Pine (Pinus densiflora) and aspen (Populus euramericana) wood meals were treated with ozone at various time schedule in acidic condition. The lignin contents and surface area of the ozone treated wood meals were determined and the enzymatic hydrolysis rate of ozonated wood meals was evaluated. The feasibility of enzymatic hydrolysis of the ozone treated wood meal was obviously influenced with the degree of delignification. After ozone treatment of wood meal for 10min, total pore volume were slightly increased in the surface of wood meal. When wood meals were treated with ozone longer than 10min, few change in the pore volume was observed. However, the area of over $50{\AA}$ of pore size is increased with ozonation time. As a conclusion, the rate of enzymatic hydrolysis of wood is more effective with the pore size distribution than the total pore volume.

• Food Science of Animal Resources
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• v.35 no.3
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• pp.350-359
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• 2015

This review focuses on the enhanced functional characteristics of enzymatic hydrolysates of whey proteins (WPHs) in food applications compared to intact whey proteins (WPs). WPs are applied in foods as whey protein concentrates (WPCs), whey protein isolates (WPIs), and WPHs. WPs are byproducts of cheese production, used in a wide range of food applications due to their nutritional validity, functional activities, and cost effectiveness. Enzymatic hydrolysis yields improved functional and nutritional benefits in contrast to heat denaturation or native applications. WPHs improve solubility over a wide range of pH, create viscosity through water binding, and promote cohesion, adhesion, and elasticity. WPHs form stronger but more flexible edible films than WPC or WPI. WPHs enhance emulsification, bind fat, and facilitate whipping, compared to intact WPs. Extensive hydrolyzed WPHs with proper heat applications are the best emulsifiers and addition of polysaccharides improves the emulsification ability of WPHs. Also, WPHs improve the sensorial properties like color, flavor, and texture but impart a bitter taste in case where extensive hydrolysis (degree of hydrolysis greater than 8%). It is important to consider the type of enzyme, hydrolysis conditions, and WPHs production method based on the nature of food application.

• Preventive Nutrition and Food Science
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• v.20 no.3
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• pp.183-189
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• 2015

In the present study, an optimum protease was selected to hydrolyze the egg white liquid protein for the antioxidant peptides. Alcalase treatment yielded the highest amount of ${\alpha}$-amino groups (15.27 mg/mL), while the control (no enzymatic hydrolysis) showed the lowest amount of ${\alpha}$-amino groups (1.53 mg/mL). Alcalase also gave the highest degree of hydrolysis (DH) value (43.2%) and was more efficient for egg white liquid hydrolysis than the other enzymes. The Alcalase hydrolysate had the highest radical-scavenging activity (82.5%) at a concentration of 5.0 mg/mL. The conditions for enzymatic hydrolysis of egg white liquid with Alcalase were selected as substrate : water ratio of 2:1. Five percent Alacalse treatment did not show significant (P>0.05) increases of DH and ${\alpha}$-amino nitrogen content after 24 hhydrolysis. Thirty two hour-hydrolysis with 5% Alcalase is sufficient to make antioxidative egg white liquid hydrolysate from egg white liquid. DPPH and ABTS radical-scavenging activities were significantly (P<0.05) higher after enzymatic digestion. These results suggest that active peptides released from egg-white protein are effective radical-scavengers. Thus, this approach may be useful for the preparation of potent antioxidant products.

• Environmental Engineering Research
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• v.19 no.1
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• pp.83-89
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• 2014

The effects of initial solid concentration and microwave irradiation (MWI) time on the hydrolysis of waste activated sludge (WAS) were investigated. MWI time strongly influenced WAS hydrolysis for all initial solid concentrations of 8.20, 31.51, and 52.88 g VSS/L. For all WAS, the volatile suspended solids (VSS) solubilization degree ranged from 35.6% to 38.4% during a total MWI time of 10 min. Soluble chemical oxygen demand (SCOD) concentration increased at a rate proportional to the decrease of VSS during the MWI. However, the clearly different VSS solubilization patterns that were observed during the MWI were explained by the 2-step hydrolysis of WAS, consisting of the initial disintegration of the easily degradable part of the sludge, followed by the subsequent disintegration of the hardly degradable part of the sludge. WAS hydrolysis rates for 3 to 6 min of MWI were significantly lower than those for less than 3 min, or more than 6 min. From these results, 3 min MWI time and WAS of 31.51 g VSS/L (centrifugal thickener WAS) showed the most efficient hydrolysis of WAS at 36.0%. The profiles of total nitrogen (T-N) concentrations corresponded well to the SCOD increases in terms of the empirical formula of bacterial cell mass ($C_5H_7O_2N$). The negligible T-N increase and pH decrease during WAS hydrolysis by MWI will allow the application of this process to subsequent biological processes, such as anaerobic digestion.

• KSBB Journal
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• v.14 no.6
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• pp.696-701
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• 1999

The enzymatic hydrolysis of Castor oil for the mass production of ricinoleic acid was studied to find out the optimum conditions such as solvents and the weight ratio of substrate to enzyme. Three different lipases were tested for the hydrolysis of castor oil: lipase from Porcine Pancrease(lipsase PP), lipase from Candida cylindracea(lipase CC), lipase from Candida Rugosa(lipase CR). The poor mass transfer in water caused a low degree of hydrolysis of castor oil. To overcome this problem, organic solvents were used. Among organic solvents tested, hydrophobic solvents gave better results of hydrolysis than hydrophilic solvents. Organic solvents also lowered or changed the effect of pH. Isopropyl ether made complete hydrolysis of castor oil. The ratio of water to isopropyl ether and the ratio of weight ratio of lipase to castor oil were important for the hydrolysis of castor oil. At 30$^{\circ}C$ castor oil was completely hydrolyzed by 4 wt% of lipase in the mixture of isopropyl ether and water(1:1 in volume).