• Food Science and Biotechnology
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• 제14권5호
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• pp.651-655
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• 2005

Enzymatic hydrolysis of shark (Squatina oculata) cartilage (SC) was optimized by response surface methodology (RSM) for chondroitin sulfate (CS) preparation. Among 11 commercial proteases, Maxazyme NNP showed highest productivity (CS yield per enzyme cost) of CS. Optimal hydrolysis conditions determined by RSM were 1.63% and 2.87 hr for enzyme concentration and hydrolysis time ($r^2\;=\;0.9527$, p<0.0l), respectively and highest yield of hydrolysate under the conditions was 42.3%. The yield ($43.1{\pm}2.1%$) and CS content ($24.8{\pm}0.1%$) of hydrolysate at optimal condition verified statistical optimization of SC enzymatic hydrolysis was valid.

• Journal of the Korean Wood Science and Technology
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• 제15권3호
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• pp.34-43
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• 1987

This study was performed to find out the types of linkage of carbohydrates in wood cell walls. To study the structure of linkage of carbohydrates in wood cell walls, we have attempted to find out the method holocellulose preparation and optimum condition of enzyme hydrolysis in holocellulose, and fractionate oligosaccharide with products that hydrolized partly by acetolysis and deacetylation in holocellulose. We have achieved four results. These results as follow; 1. At first. we reacted in wood meal $NaClO_2$ 1g per lignin lg for one hour and then the same of quantity $NaClO_2$ for four hours. Through these experiments, we have developed new holocellulose preparation method which had low loss of carbohydrates and high effect of the delignification. 2. The optimum condition of enzyme hydrolysis of holocellulose which had lignin was 0.005M sodium acetate buffer (pH 5.0). We have achieved 7.2% reducing sugar through the procedure that reactioned 0.01g holocellulose putting enzyme 0.03g for 72 hours. It may be supposed that 5.5% of lignin contained in holocellulose prevented enzyme contaction from holocellulose and so this lignin has resulted in the low efficiency of enzyme hydrolysis. 3. We did not fractionated from oligosaccharides which were preparated by the method of acetolysis and deacetylation in holocellulose. The reason is that holocellulose having a lot of lignin prevented prefectly partial hydrolysis from the method of acetolysis and deacetylation. 4. We attempted analysis of six standard substances through HPLC apparatus having sugar pak 1 column which we have changed flow rate and the column temperature variably. These six standard substances were D-glucose, D-mannose, D-xylose, D-galactose and L-rhamnose, L-arabinose, But sugar pak 1 column was not fitted analysis of four substances because D-galactose, D-mannose, D-xylose, L-rhamnose were agreement with elution time. And so, we could not analize four standard substances with sugar pak 1 column.

• 한국축산식품학회지
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• 제44권3호
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• pp.723-737
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• 2024

Yeast protein can be a nutritionally suitable auxiliary protein source in livestock food. The breakdown of proteins and thereby generating high-quality peptide, typically provides nutritional benefits. Enzyme hydrolysis has been effectively uesed to generate peptides; however, studies on the potential applications of different types of enzymes to produce yeast protein hydrolysates remain limited. This study investigated the effects of endo- (alcalase and neutrase) and exotype (flavourzyme and prozyme 2000P) enzyme treatments on yeast protein. Endotype enzymes facilitate a higher hydrolysis efficiency in yeast proteins than exotype enzymes. The highest degree of hydrolysis was observed for the protein treated with neutrase, which was followed by alcalase, prozyme 2000P, and flavourzyme. Furthermore, endotype enzyme treated proteins exhibited higher solubility than their exotype counterparts. Notably, the more uniform particle size distribution was observed in endotype treated yeast protein. Moreover, compared with the original yeast protein, the enzymatic protein hydrolysates possessed a higher content of β-sheets structures, indicating their higher structural stability. Regardless of enzyme type, enzyme treated protein possessed a higher total free amino acid content including essential amino acids. Therefore, this study provides significant insights into the production of protein hydrolysates as an alternative protein material.

• KSBB Journal
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• 제13권1호
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• pp.44-51
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• 1998

Hydrolysis and adsorption reversibility experiments were run for initial enzyme activity of 4.48, 9.65, 11.19 and 17.14U/mL at a temperature 30$^\circ C$. The chitin particle size corresponded to a mean particle diameter of 0.127mm, and the initial concentration of chitin was 10mg/mL. After approximately 2hrs, the enzyme activity remained constant in a speudo-steady state. The amounts in the bulk [E] and the amounts of enzyme adsorbed on the chitin surface [E] are plotted on Lineweaver-Burk plot to yield a linear relationship with a correlation coefficient of 0.99, a slope of 2.79cm$^-1$ and an intercept of 0.08$\textrm{cm}^2$/U. From this parameters, the values of [E$_T$] and $K_E$ were calculated to be 12.5U/cm$^2$ and 34.88U/mL. respectively, Adsorption isotherm of the enzyme on the particles showed a well developed plateau of 1.35$\times$10$^-3$, 4.72$\times$10$^-3$, 4.42$\times$10$^-3$, 8.58$\times$10$^-3$U/cm$^2$ at 30$^\circ C$. To determine the specificity of chitinase for crystalline chitin, the free energy of adsorption was measured, and its was determined as about -14.62~-18.8kJ/mol.

• Journal of Microbiology and Biotechnology
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• 제8권4호
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• pp.318-324
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• 1998

A ${\beta}$-galactosidase with high transgalactosylic activity was purified from a Bacillus species, registered as KFCC10855. The enzyme preparation showed a single protein band corresponding to a molecular mass of 150 kDa on SDS-PAGE and gave a single peak with the estimated molecular mass of 250 kDa on Sephacryl S-300 gel filtration, suggesting that the enzyme is a homodimeric protein. The amino acid and sugar analyses revealed that the enzyme is a glycoprotein, containing 19.2 weight percent of sugar moieties, and is much more abundant in hydrophilic amino acid residues than in hydrophobic residues, the mole ratio being about 2:1. The pI and optimum pH were determined to be 5.0 and 6.0, respectively. Having a temperature optimum at $70^{\circ}C$ for the hydrolysis of lactose, the enzyme showed good thermal stability. The activity of the enzyme preparation was markedly increased by the presence of exogenous Mg (II) and was decreased by the addition of EDTA. Among the metal ions examined, the most severely inhibitory effect was seen with Ag (I) and Hg (II). Further, results of protein modification by various chemical reagents implied that 1 cysteine, 1 histidine, and 2 methionine residues occur in certain critical sites of the enzyme, most likely including the active site. Enzyme kinetic parameters, measured for both hydrolysis and transgalactosylation of lactose, indicated that the enzyme has an excellent catalytic efficiency for formation of the transgalactosylic products in reaction mixtures containing high concentrations of the substrate.

• 한국식품과학회지
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• 제29권6호
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• pp.1125-1130
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• 1997

효소 분해에 의해 HVP를 생산하는데 있어서 여러 가지 효소의 조합, 효소 첨가 순서, pH, 산세척 등이 가수분해에 미치는 효과를 검토하였다 Endoprotease으로서 Neutrase와 Alcalase를 혼합하여 사용하는 것이 Alcalase를 단독 사용하는 것 보다 가수분해도가 높았으며 exoprotease인 Flavourzyme을 이용하여 2차 가수분해함으로써 60%이상의 가수분해도를 얻을 수 있었다. 2차 가수분해 시 원심분리에 의해 미반응 불용 성분을 제거하는 것은 가수분해도에 큰 영향을 미치지 않았고, 1차 가수분해 후 2차 원심분리의 수세수를 원료 현탁에 재사용하였을 경우 가수분해도 및 단백질 회수율을 높일 수 있었다. Ca이온의 첨가에 의한 Neutrase의 안정화 효과는 가수분해도에 큰 영향을 미치지 않았다. 탄수화물 분해효소의 사용과 산세척의 반복에 의해 가수분해도와 생산물의 단백질 함량이 각각 증가함을 알 수 있었다. Endoprotease과 exoprotease을 별도로 각각 처리하기보다는 동시 처리하는 것이 가수분해에 효율적이었다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제7권5호
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• pp.268-274
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• 2002

Enzymatic hydrolysis of waste office paper was evaluated using three commercial cellulases, Acremonium cellulase, Meicelase, and Cellulosin T2. Varying the enzyme loading from 1 to 10% (w/w) conversion of waste office paper to reducing sugar was investigated. The conversion increased with the increase in the enzyme loading: in the case of enzyme loading of 10% (w/w), Acremonium cellulase yielded 79%conversion of waste office paper, which was 17% higher compared to Meicelase, 13% higher than that of Cellulosin T2. Empirical model for the conversion (%) of waste office paper to re-ducing sugar (x) was derived from experimental results as follow, x = $kE^{m}t^{(aE+b)}$ where k, m, a, and b de-note empirical constants. E indicates initial enzyme concentration.

• Journal of Microbiology and Biotechnology
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• 제9권4호
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• pp.514-517
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• 1999

Hydrolysis of EFB (empty fruit bunch) derived from oil palm was studied using crude enzyme from Aspergillus terreus IMI 282743 along with commercial enzymes from Trichoderma reesei and Aspergillus niger. Hydrolysis at $40^{\circ}C$ and $50^{\circ}C$ with $\alpha$-cellulose or EFB gave significantly lower yield when commercial enzymes of T. reesei and A. niger were used and the hydrolysis time extended beyond 10 h. After 24 h of hydrolysis at $40^{\circ}C$ and $50^{\circ}C$, the filter paper activity (Fpase) from A. terreus retained as much activity as A. niger and it was significantly higher than T. reesei. Glucose concentration of 0.25% and 0.5% caused significant inhibition in the crude enzyme, but in regards to the commercial enzymes it only showed a slight effect. Crude enzymes from A. terreus could produce the highest reducing sugars when compared to commercial enzymes from T. reesei or A. niger. Nevertheless, low yield of sugar was observed for EFB for all treatments.

• Food Science and Biotechnology
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• 제18권3호
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• pp.706-711
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• 2009

Lysozyme was treated with digestive enzymes and the production of interleukin 8 (IL-8) was measured in Caco-2 cell with the peptides from lysozyme upon stimulating with lipopolysaccharide (LPS) to investigate the overall anti-inflammatory activity of lysozyme when it is in digestive tracts. Lysozyme reduced IL-8 production, and the peptides from pepsin hydrolysis of lysozyme had the similar effect. The products of trypsin digestion of lysozyme had no effect on the reduction of IL-8 production while those of pepsin-trypsin hydrolysis did. The effectiveness of lowering IL-8 production was not different by time of the peptide addition. When Caco-2 cells were pre-incubated with peptides for 24 hr, the reduction effects were observed from the peptides from pepsin hydrolysis, indicating that some of the peptides are still remaining in the cells. Therefore, it can be concluded that the IL-8 reduction effect of lysozyme against LPS still remained even after the pepsin and trypsin hydrolysis.

• Bulletin of the Korean Chemical Society
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• 제18권3호
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• pp.300-305
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• 1997

Effect of a nonionic surfactant, Tween 20 on the adsorption and kinetic mechanism for the hydrolysis of a microcrystalline cellulose, Avicel PH 101, by endoglucanase Ⅰ (Endo Ⅰ) and exoglucanase Ⅱ (Exo Ⅱ) isolated from Trichoderma viride were studied. The Langmuir isotherm parameters, amount of maximum adsorption (Amax) and adsorption equilibrium constant (Kad) for the adsorption, were obtained in the presence and the absence of nonionic surfactant. On the addition of Tween 20, the Kad and Amax values of Exo Ⅱ were decreased, while those of Endo Ⅰ were not affected. These indicate that the adsorption affinity of Exo Ⅱ on the cellulose is weakened by nonionic surfactant, and the surfactant enhanced desorption of Exo Ⅱ from insoluble substrate. The enzymatic hydrolysis of the cellulose can be described by two parallel pseudo-first order reactions using the percentages of easily (Ca) and hardly (Cb) hydrolyzable cellulose in Avicel PH 101 and associated rate constants (ka and kb). The Ca value was increased by adding Tween 20 for all enzyme samples (Exo Ⅱ, Endo Ⅰ and their 1:1 mixture) implying that the low-ordered crystalline fraction in the cellulose may be partly dispersed by surfactant. The ka value was not affect by adding Tween 20 for all enzyme samples (Exo Ⅱ, Endo Ⅰ and their 1:1 mixture). The kb value of Exo Ⅱ was increased by adding Tween 20, while that of Endo Ⅰ was not affected. This suggests that the surfactant helps the Exo Ⅱ desorb from microcrystalline cellulose, and increase the hydrolysis rate. These results were show that the increase of hydrolysis of cellulose by the nonionic surfactant is due to both the activation of Exo Ⅱ and partial defibrillation of the cellulose.