• Korean Journal of Food Science and Technology
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• v.23 no.1
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• pp.25-30
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• 1991

Chicken liver was enzymatically hydrolyzed with an alkaline protease and determined the optimal conditions of reaction temperature and time, pH and enzyme to substrate ratio(E/S ratio) for possible utilization as a protein supplementary ingredient. The functional properties of hydolysate measured were water and oil absorption capacity, emulsifying activity and viscosity and sensory properties were also evaluated. It was found that hydrolysis at $60^{\circ}C$ and pH 8.0 were most effective and the degree of hydrolysis increased with increasing E/S ratio. A decrease in water and oil absorption capacity and an increase in viscosity were found during hydrolysis. The lowest emulsifying activity and highest water absorption were measured for 1/2 hour-hydrolysate and little difference was found for those treated more than 1 hour. The sensory characteristics of odor showed no significant difference among the chicken liver hydrolysates while the brightness increased and red decreased significantly(p<0.01) as the hydrolysis proceeded.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.388.3-389
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• 2002

Kyonin(Armeniacae Semen)is the herb medicine that contains amygdalin as a major ingredient. Amygdalin in water is decomposed into benzaldehyde. HCN. and glucose by emulsin. a hydrolysis enzyme in kyonin. A useful and practical method for the optimum extraction condition of amygdalin without enzymatic hydrolysis is required. The extraction yield of amygdalin of natural formula kyonin was 0.5% from crude powers. 0.7% from small pieces. 1.2% from half pieces and 2.7% from whole pieces. (omitted)

• Food Science and Biotechnology
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• v.14 no.6
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• pp.818-822
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• 2005

Beta-1,4-mannotriose was prepared by the enzymatic hydrolysis of poonac and the subsequent elimination with yeast of monosaccharides and disaccharide from the resultant hydrolysate. The enzyme system hydrolyzed poonac and produced monosaccharides, disaccharide and ${\beta}$-1,4-mannotriose without other oligomers at the final reaction stage. Poonac (50 g) was hydrolyzed at $50^{\circ}C$ and pH 6 for 48 hr with the crude enzyme solution (500 mL) from Trichoderma harzianum. The elimination of monosaccharides and disaccharide from the hydrolysis products with a yeast (Candida guilliermondii) produced 10.5 g of crystalline [${\beta}$-1,4-mannotriose without the use of chromatographic techniques. After 48 hr of yeast cultivation, the total sugar content fell from 4.8% to 3.4%, and the average degree of polymerization (D.P) rose from 2.5 to 3.2. The preparation method presented was confirmed to be suitable for the preparation of mannotriose from poonac.

• Korean Journal of Food Science and Technology
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• v.2 no.2
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• pp.43-48
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• 1970

When of the synthetic peptides were subjected hydrolysis with Mucor-rennin which crystalline milk-clotting enzyme from Mucor pusillus, the peptides of Z-L-Glu-L- Phe-OH, Z-L-Phe-L-Tyr-OH, Z-L-Phe-L-Leu-OH, Z-L-Tyr-L-Leu and Z-L-Glu-L-Phe-OH, were found to be hydrolysis.

• Journal of Microbiology and Biotechnology
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• v.3 no.3
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• pp.194-198
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• 1993

${\beta}-1$, 4-Mannobiose was prepared by the enzymatic hydrolysis of brown copra meal and the subsequent elimination of mono-saccharides from the resultant hydrolysate with a yeast. The enzyme system hydrolyzed brown copra meal and produced monosaccharides and $\beta$-1, 4-mannobiose without other oligomers at the final stage of the reaction. Brown copra meal (30 g) was hydrolyzed at $50^{\circ}^C$ and pH 5 for 48 hr with the crude enzyme solution (300 ml) from Penicillium purpurogenum. By the elimination of monosaccharides from the hydrolysis products with a yeast (Candida parapsilosis var. komabaensis k-75), 5.2 g of crystalline mannobiose was obtained without the use of chromatographic techniques. After 50 hours of yeast cultivation, the total sugar content fell from 3.5% to 2.4%, and the average degree of polymerization rose from 1.8 to 2.2.

• Microbiology and Biotechnology Letters
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• v.18 no.3
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• pp.260-267
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• 1990

The mechanism of enzymatic hydrolysis of raw corn starch by the purified glucoamylase and a - amylase in an agitated bead reaction system was studied by investigating the changes of sugar profiles produced by each enzyme, the granular structure of raw corn starch, the amount of enzyme adsorption on residual starch, and the amylose content in residual raw starch. The sugar profiles produced by the action of exo-type glucoamylase or endo-type $\alpha$ -amylase in an agitated bead system were not recognizably differed with those produced in reaction system without bead. Without enzyme the intergenic microcrystalline structure of starch granule was not changed by the simple mechanical impact of solid media, but it was cleaved. However, starch granule was fragment into large number of small particles by the synergistic action of enzyme and attrition-milling media, identified to be the major saccharification enhancing mechanism along with the increased amount of enzyme adsorption. The amylose content decreased more readily in an agitated bead reaction system, especially by $\alpha$ -amylase.

• KSBB Journal
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• v.6 no.2
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• pp.167-174
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• 1991

Enzymatic cellulose hydrolysis depends on the several factors such as the structural features (CrI, particle size and surface area, etc.), the nature of cellulase enzyme system, the inhibitory effects of products, and enzyme deactivation. At the presence of products on the initial hydro- lysis rate of cellulose, cellobiose has more severe inhibitory effect than glucose. Othewise, the inhibition effect of products for adsorbed enzyme is related to the glucose and cellobiose conentration hyperbolically. Enzyme deactivation of FPA and ${\beta}-glucosidase$ were expressed by exponential decay profile.

• Food Science of Animal Resources
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• v.41 no.4
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• pp.608-622
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• 2021

Bioactive peptides have great potentials as nutraceutical and pharmaceutical agents that can improve human health. The objectives of this research were to produce functional peptides from ovotransferrin, a major egg white protein, using single enzyme treatments, and to analyze the properties of the hydrolysates produced. Lyophilized ovotransferrin was dissolved in distilled water at 20 mg/mL, treated with protease, elastase, papain, trypsin, or α-chymotrypsin at 1% (w/v) level of substrate, and incubated for 0-24 h at the optimal temperature of each enzyme (protease 55℃, papain 37℃, elastase 25℃, trypsin 37℃, α-chymotrypsin 37℃). The hydrolysates were tested for antioxidant, metal-chelating, and antimicrobial activities. Protease, papain, trypsin, and α-chymotrypsin hydrolyzed ovotransferrin relatively well after 3 h of incubation, but it took 24 h with elastase to reach a similar degree of hydrolysis. The hydrolysates obtained after 3 h of incubation with protease, papain, trypsin, α-chymotrypsin, and after 24 h with elastase were selected as the best products to analyze their functional properties. None of the hydrolysates exhibited antioxidant properties in the oil emulsion nor antimicrobial property at 20 mg/mL concentration. However, ovotransferrin with α-chymotrypsin and with elastase had higher Fe³⁺-chelating activities (1.06±0.88%, 1.25±0.24%) than the native ovotransferrin (0.46±0.60%). Overall, the results indicated that the single-enzyme treatments of ovotransferrin were not effective to produce peptides with antioxidant, antimicrobial, or Fe³⁺-chelating activity. Further research on the effects of enzyme combinations may be needed.

• Microbiology and Biotechnology Letters
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• v.32 no.4
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• pp.347-351
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• 2004

Hydrolysis of manno-oligosaccharides and galactomannan was studied with the purified Bacillus subtilis WL-7 mannanase from recombinant Eschericoli. The predominant products of hydrolysis were mannose, mannobiose and mannotriose. The enzyme could hydrolyze $\beta$-1 A-linked manno-oligosaccharides larger than mannobiose, but was not active on mannobiose. When the mannanase hydrolyzed manno-oligo saccharides of degree of polymerization(DP) 4-6, it was more active on the substrate of higher DP. Based on analysis of transient reaction products by TLC, the enzyme was found to have a preference for internal $\beta$-IA-mannosidic linkages, which are the central mannosidic bond of mannotetraose and the two middle mannosidic bonds of mannopentaose. The $\beta$-l A-mannosidic bonds situated at the second and fourth positions from the nonreducing end of mannohexaose were preferenhydrolyzed by the mannanase. Locust bean gum(LBG) was enzymatically hydrolyzed with higher efficiency than guar gum, resulting that amount of reducing sugars was liberated more efficiently from LBG than guar gum with same activity of mannanase.

• Korean Journal of Food Science and Technology
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• v.31 no.3
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• pp.727-733
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• 1999

Endo- and exoproteases were used to hydrolyze Alaska pollack processing scrap. In 2 stage hydrolysis, the optimal conditions by Protamex were: temperature, $45.8^{\circ}C$; pH, 6.73; enzyme concentration, 0.11%; time, 105.5 min, whereas those by Flavourzyme were: temperature, $42.0^{\circ}C$; pH, 6.54; enzyme concentration, 0.28%; time, 20.4 hrs. But, the optimal conditions of 1 stage hydrolysis by equal proportion of Protamex and Flavourzyme were: temperature, $52.9^{\circ}C$; pH, 6.3; enzyme concentration, 0.46%; time 10.9 hrs. The contents of carbohydrate and ash were higher in the 2 stage hydrolyzate than the 1 stage, while that of crude lipid was in the reverse order. There were no significant differences in the contents of moisture and crude protein between both methods. The contents of total creatine and IMP, and viable cell counts were higher in the 1 stage hydrolyzate than the 2 stage, while the contents of TMAO, TMA, and Hx was in the reverse order. But, there were no significant differences in the contents of amino-N and color between both methods. The free amino acid contents of the 1 and 2 stage hydrolyzate were 2,741.77 and 3,529.47 mg/100 mL, respectively.