• Korean Journal of Agricultural Science
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• v.25 no.1
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• pp.107-117
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• 1998

Ths studies was carried out to investigate the processing possibility of pheasant meat extracts treated with proteases. The crude protein, aminonitrogen, degree of hydrolysis, yield and amino acid composition of pheasant meat extracts when it was treated with proteases at various temperature and reaction time were analyzed. The crude protein contents of pheasant meat extracts processed in $130^{\circ}C$ were more than when it was done in $100^{\circ}C$, but the contents of aminonitrogen were not quite different between two processing temperature. The content of crude protein and aminonitrogen when pheasant meat was hydrolyzed with protease NP and prozyme A. The yields of pheasant meat extracts, when pheasant meat were treated at $100^{\circ}C$ and $130^{\circ}C$, were from 2.24 to 7.10% and from 5.51 to 10.45%, respectively. And the yield of extraction depended on extraction temperature, kinds of enzyme, amount of enzyme, extraction time. The content of aminonitrogen in pheasant meat extracts treated with enzyme was much higher than any other treatments. And it depended on amount of enzyme, extraction time and temperature. The amount of the amino acids in pheasant meat extracts treated by protease NP were eminently higher than by heat at $100^{\circ}C$ or $130^{\circ}C$.

• Ceramist
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• v.21 no.3
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• pp.204-215
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• 2018

Proteases are one of the most abundant classes of enzymes in living organisms and have been considered major targets for drug development. However, despite the ability to specifically cleave their substrates, many attempts to assay protease activity have generally relied upon the use of gel zymography or fluorophore-labeled peptide substrates, which is limited in rapid and multiplex analysis. Here we review the recent advances in nanoparticle (NP)-utilized assays of protease activity focused on in vitro and cell imaging-based approaches. Owing to large surface area and unprecedented physical properties of NPs, these approaches are anticipated to facilitate many applications related to protease activity-based disease diagnosis and drug discovery.

• Korean journal of applied entomology
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• v.27 no.4
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• pp.211-218
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• 1988

Polyhedral proteins and the endogenous alkaline protease associated with larval-derived polyhedra of nuclear viruses isolated from Spodoptera litura, Bombyx mori, and Hyphantria cunea were investigated. Polyhedral proteins prepared under alkaline protease heat-inactivated condition were separated as one band with 31Kd in S. litura a H. cunea NpV and 30Kd in B. mori NPV by the SDS-polyacrylamide gel electroptoresis. Whereas polyhedral proteins without heat-inactivation were degraded into smaller polypeptides with a certain pattern in alkaline solution. The results of double-immunodiffusion and western blot analysis with antisera against polyhedral proteins indicated that those three polyhedral proteins had common antigenic determinants and the degradation of polyhedral proteins by alkaline protease could be confirmed.

• Korean Journal of Food Science and Technology
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• v.34 no.4
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• pp.570-576
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• 2002

For the utilization of the by-products of whelk processing, whelk internal organ with the addition of commercial proteolytic enzymes - Flavourzyme, Neutrase, Protease NP, Prozyme - were used to make jeotgal, Korean traditional salted and fermented seafood sauce. The products were prepared at salt concentration of 25% with enzyme contents 0.05 and 0.1%. The samples were stored at $10^{\circ}C$ and the chemical properties were evaluated for 6 months. The pH in all samples were decreased from near 6.8 in the beginning stage to 6.1-6.4 in the final stage of incubation. Amino nitrogen of jeotgal increased with enzyme concentration and showed maximum value, 646 mg%, at 0.1% of Flavourzyme. Total nitrogen content was increased till four months, but rapidly decreased after that. Protein degradations of whelk internal organ during maturation of jeotgals were investigated by SDS-PAGE. The patterns of degradation were different with added enzymes.

• Korean Journal of Food Science and Technology
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• v.40 no.2
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• pp.190-193
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• 2008

Bovine hepatic extract is recognized as possessing detoxifying activity against various liver diseases. In orderto develop a process for its mass production, various enzymatic hydrolysis conditions were tested, and bovine hepatic extracts were prepared. These extracts were then examined for composition, microorganism levels, and vitamin $B_{12}$ content. Among the enzymes tested, papain was selected based on yields for dry residue and amino nitrogen. The other enzymes tested included bromelain, ficin, pancreatin, and protease NP. The optimal hydrolysis conditions were established at 65$^{\circ}C$ for 24 hr, with an addition of 1%(w/w) papain to the beef liver. The prepared spray-dried bovine hepatic extract showed an 11% recovery yield on a raw beef liver basis, with 95% dry residue and 11.8% total nitrogen content. Microorganisms were not detected in the dried extract, and its vitamin $B_{12}$ content was 4.1 ${\mu}$g/g. In summary, the conditions established in this study could be applied for the high yield mass production of bovine hepatic extract.

• Korean Journal of Microbiology
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• v.30 no.6
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• pp.528-532
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• 1992

The ATP-dependent protease. Clp P from Esehaichia coli has been increase the stahility with or without detergent as Triton X-100 and NP-40 in the Clp P. The C]p P proteolytic activity was remained to 0.1 M salt by $Na^{-1}$, $K^{+}$, $Li^{+}$ but was inhihited by $SO_4^{2}$. An active ATPase site in Clp A is required for A TP-dependent proteolysis by Clp protease as

• BMB Reports
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• v.44 no.10
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• pp.665-668
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• 2011

In order to clarify the impact of Ca-binding sites (Ca1 and 2) on the conformational stability of neutral proteases (NPs), we have analyzed the thermal, pH and organic solvent stability of a NP variant, V189P/A195E/G203D/A268E (Q-mutant), from Salinovibrio proteolyticus. This mutant has shown to bind calcium more tightly than the wild-type (WT) at Ca1 and to possess Ca2. Q-mutant was resisted against autolysis, thermoinactivation and pH denaturation in a Ca-dependent manner and exhibited better activity in organic solvents compared to the WT enzyme. These results imply that Ca1 and Ca2 are important for the conformational stability of NPs.