• Food Science of Animal Resources
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• v.42 no.3
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• pp.441-454
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• 2022

This study aimed to determine the effect of enzyme, guar gum, and pressure processing on the digestibility and physicochemical properties of age-friendly liver sausages. Liver sausages were manufactured by adding proteolytic enzyme (Bromelain) and guar gum, and pressure-cooking (0.06 MPa), with the following treatments: control, without proteolytic enzyme; T1, proteolytic enzyme; T2, proteolytic enzyme and guar gum; T3, pressure-cooking; T4, proteolytic enzyme and pressure-cooking; T5, proteolytic enzyme, guar gum, and pressure-cooking. The pH was high in the enzyme- and pressure-processed groups. The pressure-processed groups had lower apparent viscosity than other cooking groups, and it decreased during enzyme treatment. Hardness was lower in the enzyme- and pressure-processed groups than in the control, and the T4 was the lowest. Digestibility was the highest in T4 at 82.58%, and there was no significant difference with that in T5. The general cooking group with enzyme and guar gum also showed higher digestibility than the control (77.50%). As a result of the sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the enzyme- and pressure-treated groups (T4, T5) were degraded more into low-molecular-weight peptides (≤37 kDa) than the control and other treatments. Viscoelasticity showed similar trends for viscous and elastic moduli. Similarly, combined pressure processing and enzymatic treatment decreased viscoelasticity, while guar gum increased elasticity but decreased viscosity. Therefore, the tenderized physical properties and improved digestibility by enzyme and pressurization treatment could be used to produce age-friendly spreadable liver sausages.

• The Korean Journal of Food And Nutrition
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• v.36 no.6
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• pp.526-534
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• 2023

To improve usability of super sweet corn, extracts were prepared with hydrolytic enzyme and changes in physicochemical and antioxidant properties were analyzed. Soluble solids and reducing sugars contents were higher in all enzyme treatment groups than in the control. When enzyme treatment time increased, contents of soluble solids and reducing sugars were also increased. There was no significant difference in lightness between treatment groups, with redness showing the highest value in the control and yellowness showing the highest value in the invertase treatment group. Free sugar content in the control was the lowest. However free sugar content in the enzyme combination treatment group was increased by more than four times compared to that in the control. Contents of ascorbic acid, flavonoids and polyphenols were higher in the enzyme treatment group than in the control. In particular, the enzyme combination treatment group showed the highest content. DPPH and ABTS radical scavenging abilities were significantly higher in all enzyme treatment groups than in the control. Radical scavenging abilities of cellulase treatment group and enzyme combination treatment group showed high activity. The activity increased when enzyme treatment time increased. The combined enzyme treatment method for super sweet corn was suitable for food processing.

• Preventive Nutrition and Food Science
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• v.11 no.2
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• pp.127-132
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• 2006

Bacillus sp. strain K-l, which produces a strong fibrinolytic enzyme, was isolated from chongkukjang, a traditional Korean fermented soybean paste. The fibrinolytic enzyme was purified from chongkukjang base by using ammonium sulfate fractionation and chromatographic techniques. Purified enzyme, CK K-1 was demonstrated to be homogeneous by SDS-PAGE and isoelectric focusing electrophoresis, and has molecular mass of a 12.4 kDa and a pI of 8.0. The optimal reaction pH value and temperature were 8.0 and $40^{\circ}C$, respectively. Phenyl-methyl-sulfonyl-fluoride (PMSF; serine protease inhibitor), ethylene-diamine-tetra-acetic acid (EDTA; metallo protease inhibitor), copper ion, ferric ion and lead ion inhibited the enzyme activity. These results indicated that the fibrinolytic enzyme is a metallo-serine protease and different from nattokinase and chongkukjangkinase.

• Korean Journal of Food Science and Technology
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• v.25 no.3
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• pp.238-242
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• 1993

For the Purpose of utilizing tannins in the functional foods and crude drugs, the enzyme inhibition of tannins isolated from Korean green tea were determined. Acetone extract from Korean green tea showed inhibition effect against the angiotensin converting enzyme. The galloyl tannins showed higher inhibition activity against angioteosin converting enzyme than the nongalloyl tannins. In terms of stereo isomers, (-)-epicatechins had higher inhibition activity than the (+ )-catechins. The synergistic activity was also observed. Tannins isolated from Korean green tea appeared to be incompetitive inhibitor against the angiotensin converting enzyme.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.6
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• pp.973-979
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• 1994

Microorganisms, including the strain IJ-3 isolated from soil, were found to secrete an extracellular soybean protein coagulating enzyme and the strain, IJ-3 was identified as Genus Bacillus according to the Bergey's manual . The enzyme coagulated protein in soymilk , thus forming a curd at pHs 5.8-6.4 and at 55-75℃. The optimum temperature for soybean protein coagulating activity was 65-75℃ and the enzyme was stable at temperature below 50℃ and was found to be stable with about 60-100% of the original activity at a with pH ranges(pH6-7). The molecular weight of enzyme was estimated to be 28,000 by SDS-PAGE. The curd formed with the enzyme from Bacilus sp. IJ-3 has a smooth texture, and a mild taste without any bitterness or a beany flavor.

• Journal of Microbiology and Biotechnology
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• v.17 no.5
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• pp.792-799
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• 2007

A gene encoding a putative glycogen-debranching enzyme in Sulfolobus shibatae(abbreviated as SSGDE) was cloned and expressed in Escherichia coli. The recombinant enzyme was purified to homogeneity by heat treatment and Ni-NTA affinity chromatography. The recombinant SSGDE was extremely thermostable, with an optimal temperature at $85^{\circ}C$. The enzyme had an optimum pH of 5.5 and was highly stable from pH 4.5 to 6.5. The substrate specificity of SSGDE suggested that it possesses characteristics of both amylo-1,6-glucosidase and $\alpha$-1,4-glucanotransferase. SSGDE clearly hydrolyzed pullulan to maltotriose, and $6-O-\alpha-maltosyl-\beta-cyclodextrin(G2-\beta-CD)$ to maltose and $\beta$-cyclodextrin. At the same time, SSGDE transferred maltooligosyl residues to the maltooligosaccharides employed, and maltosyl residues to $G2-\beta-CD$. The enzyme preferentially hydrolyzed amylopectin, followed in a decreasing order by glycogen, pullulan, and amylose. Therefore, the present results suggest that the glycogen-debranching enzyme from S. shibatae may have industrial application for the efficient debranching and modification of starch to dextrins at a high temperature.

• Preventive Nutrition and Food Science
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• v.2 no.1
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• pp.55-60
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• 1997

A lysosomal and matrix degrading enzyme $\beta$-glucuronidase activity was measured in BALS/c mice fed high and low Ca in combination with the i.p. adminstration of calcium-regulating hormones including parathyoid hormone(PTH), calcitonin(CT) and cholecalciferol(Vit D). After feeding experimental diets for five weeks, mice were sacrificed by cervical dislocation and the enzyme was fluometrically measured at 440nm. $\beta$-Glucuronidase activity was inhibited by high calcium in the diet. in addition, vitamin D also inhibited the enzyme activity in the serum regardless of the level of dietary calcium. In contrast, PTH has shown to stimulate the enzyme at all the levels of dietary calcium. Calcitonin, and inhibitor of PTH action for bone resorption, revealed to curb PTH effect in this enzyme, whereas CT stimulated the action of vitamin D in the serum. The above results led us to conclude that osteoclastic bone resorption and senile osteoporosis may be reduced by adequate dietary calcium and vitamin D.

• Microbiology and Biotechnology Letters
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• v.25 no.1
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• pp.56-61
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• 1997

An alkaline protease producing microorganism was isolated from korean traditional Meju and identified as Scopulariopsis brevicaulis. The optimum culture condition of Scopulariopsis brevicaulis for the production of alkaline protease was as follow: 2% soluble starch, 0.2$, tryptophan, 0.1% (NH$_{4}$) $_{2}$S$_{2}$O$_{8}$ 0.2% NaHPO$_{4}$, pH 7.5, 35$\CIRC $C. The optimum pH and temperature for the enzyme activity of alkaline protease producing Scopulariopsis brevicaulis were pH 9.0 and 50$\circ $C, respectively. The enzyme was relatively stable at pH 6.0~11.0 and at temperature below 40$\circ $C. The activity of the enzyme was inhibited by Hg$^{2+}$ whereas Cu$^{2+}$ gave rather activating effects on the enzyme activity. Phenylmethanesulfonyl fluoride inhibited the enzyme activity. This result indicates that serine is very important role in this enzyme. Km value for casein was 1.2410$^{4}$ M/L, V$_{max}$ value for casein was 25.99 $\mu $g/min. This enzyme hydrolyzed casein more rapidly than the hemoglobin.

• Fisheries and Aquatic Sciences
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• v.1 no.2
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• pp.209-215
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• 1998

Trypsin-like enzyme was purified from shrimp hepatopancreas through Q-Sepharose ionic exchange, benzamidine Sepharose-6B affinity, and Superdex 75 gel chromatography. Purity of trypsin-like enzyme was increased 69-fold with $44\%$ yield. The enzyme consisted of a single polypeptide chain with a molecular weight (M.W.) of 32 kDa judged by sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE). The enzyme was completely inactivated by serine enzyme inhibitors such as soybean trypsin inhibitor (SBTI), tosyl-L­lysine chloromethyl ketone (TLCK), and leupeptin. However, the enzyme was not affected by tosyl-L-phenylalanine chloromethyl ketone (TPCK) which is a chymotrypsin specific inhibitor. The enzyme had no activity against benzoyl-tyrosine ethyl ester (BTEE) which is a chymotrypsin specific substrate. The enzyme showed high activity on the carboxyl terminal of Phe, Tyr. Glu, Arg, and Asp. However. no activity was detected against the carboxyl terminal of Pro, Trp, Cys, Gly, Val, and Ala.

• Journal of Microbiology and Biotechnology
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• v.1 no.2
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• pp.102-110
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• 1991

Alkalophilic Bacillus sp. YJ-451, which was isolated from soil at several area in Korea, produced a novel type of bacteriolytic enzyme (cell wall peptidoglycan hydrolase) extracellulary. The cell wall hydrolytic activity was identified as a clear zone on sodium dodecyl sulfate polyacrylamide gel electrophoresis containing 0.2% (w/v) cell wall of Bacillus sp. as substrate. This enzyme was successively purified 66 fold with 3.2% yield in culture broth by ammonium sulfate precipitation, CM-cellulose column chromatography, and gel filtration, followed by hydroxylapatite column chromatography. The molecular weight of the purified enzyme was estimated to be 27,000 by sodium dodecyl sulfate polyacrylamide gel electrophoresis and gel filtration column chromatography. The optimum pH and temperature for the activity of the enzyme were pH 10.0 and $50^{\circ}C$, respectively. The enzyme was stable between pH 5.0 and 10.0 and up to $40^{\circ}C$. Among the microorganisms used in this experiment the enzyme was active against most of gram negative strains and the genus Bacillus such as B. megaterium, B. licheniformis, B. circulans, B. pumilus, B. macerans, B. polymyxa. The release of dinitrophenylglutamic acid but not reducing group from cell wall peptidoglycan digested by the enzyme suggested that the enzyme is a kind of peptidase which hydrolyzes the peptide bond at the amino group of D-glutamic acid in the peptidoglycan.