• Microbiology and Biotechnology Letters
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• v.14 no.6
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• pp.467-471
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• 1986

Yeast cell wall lytic enzyme was purified from Fusarium moniliforme by ammonium sulfate fractionation and gel column chromatography. The lytic activity was found to consist of three enzyme activities which were resolved on Sephadex G-100. The first peak on chromatogram exhibited proteolytic, lytic and laminarinase activities, and the second had both lytic and laminarinase activities, whereas the third peak was shown to contain lytic activity only. Three enzyme activities showed the synergistic effect and reducing agents accelerated the yeast roil wall lysis. This indicates that lytic, proteolytic and laminarinase activity acted cooperatively in the lysis of intact cells. Tannic acid precipitate of crude enzyme constituted of three enzyme activities had a high lytic activity on viable yeast cell and has proved useful in yeast protoplast formation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.4
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• pp.458-465
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• 1999

Distribution of the proteolytic activities of crude pretense extracted from the viscera of ten kinds of fish was examined. Their proteolytic activities on proteinous substrates (azocasein, hemoglobin, and casein) from the viscera of anchovy, bastard flatfish, mackerel and red sea bream were higher than those of other fishes, and the crude pretenses were further fractoinated with acetone or ammonium sulfate. Optimum concentrations for pretenses fractionation were $0\~55\%$ for acetone and $30\~70\%$ for ammonium sulfate. The fractionated viscera pretense of mackerel showed the highest proteolytic activity among four kinds of fishes. Activities of cathepsin D- and pepsin-like enzymes at pH 3.0, cathepsin L-, B-, H- and G-like enzyme at pH 6,0, and Hypsin- and chymotrypsin- like enzymes (pH 8.0) were detected in the fractionated viscera pretense, whereas activities of cathepsin L- and chymoeypsin-like enzyme were observed in commercial pretenses. Proteolytic activities of Alcalase, Protamex, and Aroase AP-10 for azocasein were slightly higher than the fractionated viscera pretenses, but their amidolytic activities at pH 6.0 and 8.0 toward synthetic substrates were lower than counterpart. The fractionated pretenses from fish viscera would be utilized as commercial pretenses.

• The Korean Journal of Food And Nutrition
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• v.11 no.5
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• pp.576-579
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• 1998

Water extract of mulberry tree barks(Morus alba Linne) was studied for its proteolytic activity. Protein content of the extract was 1.12mg/ml and its specific activity was 5.14U/ml. The enzyme was active on various proteins : the relative acitities were 100 for casein, 63 for albumin, 58 for collagen, 45 for hemoglobin and 36 gelatin, respectively. There suggested that the ability of the enzyme to hydrolyze meat was relatively high since those are major meat proteins. Optimum pH and temperature for proteolytic activity were : pH 6.0 and 6$0^{\circ}C$. And the enzyme was stable at the pH range of 6.0 to 7.0 and temperature between 50 and 8$0^{\circ}C$. Apparent proteolytic activities could support some scientific grounds of traditional application of mulberry tree barks to home cooking for meat tenderization.

• Food Science and Biotechnology
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• v.17 no.4
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• pp.873-877
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• 2008

Native soy protein isolate (SPI) was hydrolyzed with 4 different proteolytic enzymes, including bromelain, papain, Neutrase, and Flavourzyme. SPI hydrolysates with the degree of hydrolysis (DH) in range of 6 to 15% were prepared by each enzyme. The angiotensin 1 converting enzyme (ACE) inhibitory and the antioxidant activities of the SPI hydrolysates, such as superoxide dismutase-like activity and inhibition of the linoleic acid autoxidation, were evaluated. Overall, as the DH increased, all evaluated bioactivities of the SPI hydrolysates significantly increased. The significantly highest ACE inhibitory and antioxidant activities were found in hydrolysates made with papain and bromelain, respectively. SPI hydrolysates by Flavourzyme showed the significantly lowest activity in all tested bioactivities. The results suggested that ACE inhibitory and antioxidant activities of SPI hydrolysates were determined by the DH and by the enzyme used.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.6
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• pp.1116-1121
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• 1997

Effects of gamma irradiation onf the activity and the properties(amino acid compositions, in vitro digestibility and SDS-PAGE pattern) of proteolytic enzymes were investigated. The proteolytic activity of soluble human serine protease, enzyme in kiwi and pineapple decreased 10% and 30~65% by 5 kGy and 30 kGy, respectively. In dried pancreatin and lysozyme, the proteolytic and antimicrobial activities decreased 6~14% and 10~20% by 5kGy and 40kGy, respectively. The analysis of above 10kGy-irradiated soluble human serine protease by SDS-PAGE revealed radiolysis of the enzyme into protein or peptides of lower molecular weights. The irradiation of skim milk, hammastein casein, and lysozyme up to 40kGy had no deleterious effect on either the in vitro digestibility or amino acid compositions.

• Journal of fish pathology
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• v.21 no.3
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• pp.247-257
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• 2008

To understand the activity of non-specific defence factors in cultured Sebastes, the antibacterial effect of the serum, skin mucus and homogenate of various organs from cultured oblong rockfish (Sebastes oblongus) and rockfish(Sebastes schlegeli) against pathogenic bacteria, Aeromonas hydrophila, Edwardsiella tarda, Vibrio anguillarum, and Streptococcus sp. was compared with that of flounder(Paralichthys olivaceus) and seabass(Leteolabrax japonicus). And the activities of proteolytic enzyme, chitinolytic enzyme and haemolycin as non-specific defence factor were investigated on the oblong rockfish and rockfish. Samples from oblong rockfish showed the highest antibacterial activity by lysoplate assay on agar plate mixed with pathogens, followed in descending order by rockfish, seabass, and flounder. Turbidimetric assay was carried to evaluate the lysozyme activity of fish samples against lyophilized cells of Micrococcus lysodeiktikus. The serum, kidney, liver, stomach, intestine and eyeball of oblong rockfish and the mucus and gill of rockfish appeared to have the highest lysozyme activity among the fish strains investigated. All samples except skin mucus, liver, and eyeball of oblong rockfish and rockfish showed proteolytic enzyme activity. Chitinolytic enzyme activity was showed in random sampling and haemolytic activity was remarkable in oblong rockfish. Therefore, Sebastes strain was proved to have effective defense mechanisms based on the antibacterial activities, and lysozyme, proteolytic enzyme, chitinolytic enzyme, and haemolycin were considered to act as the non-specific defence factor of Sebastes.

• Fisheries and Aquatic Sciences
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• v.18 no.4
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• pp.349-357
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• 2015

To reutilize fisheries waste, we isolated a bacterial strain from a coastal area located in Busan. It was identified as Bacillus licheniformis TK3-Y. Using plate assay and 500-mL flask experiments, we found that the isolate simultaneously possessed cellulolytic, proteolytic, and lipolytic activities with salt tolerance. 10% (v/v) inoculums, were used to examine the biodegradation characteristics of the TK3-Y strain on carboxymethylcellulose, skim milk, and olive oil media. The optimum conditions for pH, temperature, agitation speed, and NaCl concentration on each 1% substrate were 6, $50^{\circ}C$, 180 rpm, and 17.5%, respectively. Under optimal conditions, the TK3-Y strain showed 1.07 U/mL cellulolytic, 1,426 U/mL proteolytic, and 6.45 U/mL lipolytic activities. Each enzyme was stable within a range of 17.5-35% NaCl. Therefore, the salt tolerance ability of strain TK3-Y was superior to other related strains. In degradation of a mixed medium containing all three substrates, both the cellulolytic and proteolytic activities were somewhat lower than those on each single substrate, while the lipolytic activity was somewhat higher. From the above results, the TK3-Y strain appears to be a good candidate for use in the efficient treatment of fisheries waste in which components are not collected separately.

• Journal of Ginseng Research
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• v.13 no.1
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• pp.92-97
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• 1989

This study investigated the effects of high light intensity (100 KLw) and high temperature (45 ℃, dark) on enzyme (glucose-6-phosphate dehydrogenase, acid phosphatase, catalase, peroxidase, and proteinase) activities and characteristics of Panax ginseng C.A. Meyer leaves. Enzyme activity and protein content decreased rapidly under treatment with high light intensity In P ginseng the thermal stabilities of catalase and peroxidase were high (above 70%), and the coagulation rates of soluble proteins were low (below 17%). Therefore, the decrease in enzyme activity and protein content was not caused by increase in leaf temperature due to the high light intensity, but by increase in proteolytic activities. The photochemical formation rate of superoxide radical (O-2) was higher in the P ginseng leaf extracts than in Solanum nigmm, and was accelerated by addition of crude saponin to the buffer extracts.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.3
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• pp.280-286
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• 2021

This study was performed to screen the antimicrobial activities and proteolytic enzyme stability of the acidified extract of the Blue mussel Mytilus edulis. The acidified extract showed potent antimicrobial activities against Gram-positive bacteria, Bacillus subtilis, and Gram-negative bacteria, Escherichia coli D31, but had no activity against Candida albicans. Treatment of extract with trypsin completely abolished all or significant antibacterial activity against the tested bacteria, but slightly decreased antimicrobial activity against B. subtilis, and treatment of extract with chymotrypsin retained almost antibacterial activity against the tested bacteria except for E. coli D31. To confirm the additional enzyme stability of the extract, antimicrobial activity of the extract was tested after treated with several enzymes. Enzymes treated extract showed potent antimicrobial activity against B. subtilis and its activity was also retained for 5 h after trypsin treatments. Non-proteinaceous materials in the acidified extract also showed strong DNA-binding ability but did not show bacterial membrane permeabilizing ability. All our results indicate that mussel extract might contain the proteinaceous or non-proteinaceous antibacterial materials target not bacterial membrane but intracellular components. These results could be used to develop mussel extract as an additive for the improvement of stability or antimicrobial activity of antibiotics against specific bacteria.

• Food Science of Animal Resources
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• v.41 no.5
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• pp.869-882
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• 2021

Sodium chloride (NaCl) replacement with calcium chloride (CaCl₂) effect on protein solubility, proteolytic enzyme and quality characteristics of a chicken soup prepared from spent hen (SH) chicken were investigated. By means of immerse marination prior to cooking, a total of 60 skinless SH breast meat were randomly allocated into ten groups admitted to treatments with marinade solution containing sodium tripolyphosphate (STPP) and reduced percentage of NaCl with CaCl₂ at 0%, 25%, 50%, 75%, and 100% at 4±2℃ for 20 h. STPP was adjusted to 0.5% for all treatments and NaCl replacement at 0% was used as control. The different methods, particularly boiling at 100℃ and retorting at 121℃, 1.5 kgf/cm² for 60 minutes, were applied following marination. An upregulation of cathepsin-B and caspase-3 enzymes were a consequences from a higher percentage of CaCl₂ within meat environment. Accordingly, modified the protein solubility in particular the myofibrillar and total protein solubility. In addition, a significant increase in water holding capacity (WHC), pH value, myofibril fragmentation index (MFI), and moisture content was obtained due to salt replacement (p<0.05). Limited effect was observed for shear force value, collagen content and cooking yield. Eventually, this study implied that although protelytic enzyme and protein solubility was upregulated by the replacement of NaCl with CaCl₂ at >75%, extensive effect on texture properties was not observed. Therefore, NaCl replacement at 75% could be a promising strategy for quality improvement of SH chicken soup.