• Preventive Nutrition and Food Science
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• v.13 no.3
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• pp.196-203
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• 2008

Hwangtae, dried Alaska pollack, is a major storage product in the fish processing industry. Hwangtae is prepared by removing the internal organs and drying outdoors during the cold witner months by allowing it to thaw during the daytime and re-freeze at night under sub-zero ($-10^{\circ}C$) conditions and gradually dry from December until the next April for around 5 months from Myungtae. In this study, ground Hwangtae was hydrolyzed using two proteolytic enzymes (pepsin and alcalase) which produced five soluble active peptides from Hwangtae (yellowish dried Pollack, Theragra chalcogramma) protein. Two different peptides with strong antioxidative activity were isolated from the hydrolysate using consecutive chromatographic methods of Sephadex G-25 gel, ion-exchange chromatography on a Sepharose-Sephadex C-25 gel, and high-performance liquid chromatography. The isolated peptides, APO1 and APO2, were composed of 16 and 13 amino acid residues, respectively. Both peptides contained a Gly residue at the C-terminus and the repeating motif Gly-Pro-Hyp. The peptide with a molecular weight less than 1,000 Daltons (APACE) obtained from enzymatic hydrolysates of Hwangtae exhibited the highest ACE inhibitory activity. The APACE peptides was composed of 4 amino acid residues (Gly-Leu-Leu-Pro). These results suggest that Hwangtae hydrolysates could be a good source of peptides with ACE inhibitory activity. Biochemical analysis indicated that two 70 kDa peptides (APG1 and APG2) isolated from the hydrolysate had gelatinoytic activity, which was shown to be a calcium dependent protease type as showed by gelatin SDS PAGE.

• International Journal of Oral Biology
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• v.35 no.4
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• pp.153-158
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• 2010

Angelica decursiva has been used in Korean traditional medicine as an antitussive, an analgesic, an antipyretic and a cough remedy. However, the anti-cancer properties of Angelica decursiva have not yet been well defined. In our current study the cytotoxic activity of ethanol extracts of Angelica decursiva root (EEAD) and the mechanism of cell death exhibited by EEAD were examined in FaDu human head and neck squamous cell carcinoma cells. The cytotoxic effects of EEAD upon the growth of FaDu cells were examined with an MTT assay. In addition, the mechanism of cell death induced by EEAD was evaluated by DNA fragmentation analysis, immunoblotting and caspase activation measurements. EEAD induced apoptotic cell death in FaDu cells in a concentration- and time-dependent manner, as determined by MTT assay and DNA fragmentation analysis. Furthermore, the proteolytic processing of caspase-3, -7 and -9 was increased by EEAD treatment of FaDu cells. In addition, the activation of caspase-3 and -7 was detected in living FaDu cells by fluorescence microscopy. These results suggest that EEAD can induce apoptosis and suppress cell growth in cancer cells and may have utility as a future anticancer therapy.

• The Journal of Internal Korean Medicine
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• v.27 no.3
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• pp.603-616
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• 2006

The water extract of Gamiyaengshinhwan (GYH), has been used in vitro tests for its beneficial effects on neuronal survival and neuroprotective functions, particularly in connection with CT105-related dementias and Alzheimer's disease(AD). CT105 derived from proteolytic processing of the $\beta$-amyloid precursor protein (APP), including the amyloid-$\beta$ peptide ($A{\beta}$), plays a critical role in the pathogenesis of Alzheimer's dementia. We determined that transfected overexpressing APP695 and $A{\beta}$ CT105 have a profound attenuation in the Increase in CT105 expressing neuro2A cells from GYH. Experimental evidence indicates that GYH protects against neuronal damage from cells, but its cellular and molecular mechanisms remain unknown. Using a neuroblastoma cell line stably expressing CT105-associated neuronal degeneration, we demonstrated that GYH inhibits formation of amyloid-$\beta$ fragment ($A{\beta}$ CT105). which are the characteristic, and possibly causative, features of AD. The decreased CT105 $A{\beta}$ in the presence of GYH was observed in the conditioned medium of this CT105-secreting cell line under in vitro. In the cells, GYH significantly attenuated mitochondrion-initiated apoptosis and decreased the activity of Bax, a key enzyme in the apoptosis cell-signaling cascade. These results suggest that neuronal damage in AD might be due to two factors: a direct CT05 toxicity and the apoptosis initiated by the mitochondria. Multiple cellular and molecular neuroprotective mechanisms, including attenuation of apoptosis and direct inhibition of CT105 aggregation, underlie the neuroprotective effects of GYH.

• Food Science and Biotechnology
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• v.17 no.6
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• pp.1165-1170
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• 2008

The deposition of the amyloid $\beta}$ ($A{\beta}$)-peptide following proteolytic processing of amyloid precursor protein (APP) by $\beta$-secretase (BACE1) and $\gamma$-secretase is critical feature in the progress of Alzheimer's disease (AD). Consequently, BACE1, a key enzyme in the production of $A{\beta}$, is a prime target for therapeutic intervention in AD. In the course of searching for BACE1 inhibitors from natural sources, the ethyl acetate fraction of Petasites japonicus showed potent inhibitory activity. Two BACE1 inhibitors quercetin (QC) and kaempferol 3-O-(6"-acetyl)-$\beta$-glucopyranoside (KAG) were isolated from P. japonicus by activity-guided purification. QC, in particular, non-competitively attenuated BACE1 activity with $IC_{50}$ value of $2.1{\times}10^{-6}\;M$ and $K_i$ value of $3.7{\times}10^{-6}\;M$. Both compounds exhibited less inhibition of $\alpha$-secreatase (TACE) and other serine proteases including chymotrypsin, trypsin, and elastase, suggesting that they ere relatively specific and selective inhibitors to BACE1. Furthermore, both compounds significantly reduced the extracellular $A{\beta}$ secretion in $APP_{695}$-transfected B103 cells.

• Journal of Microbiology and Biotechnology
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• v.32 no.1
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• pp.99-109
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• 2022

This study is the first report on production and characterization of the enzyme from an Ornithinibacillus species. A 4.2-fold increase in the extracellular protease (called L9^T) production from Ornithinibacillus caprae L9^T was achieved through the one-factor-at-a-time approach and response surface methodological optimization. L9^T protease exhibited a unique protein band with a mass of 25.9 kDa upon sodium dodecyl sulfate-polyacrylamide gel electrophoresis. This novel protease was active over a range of pH (4-13), temperatures (30-80℃) and salt concentrations (0-220 g/l), with the maximal activity observed at pH 7, 70℃ and 20 g/l NaCl. Proteolytic activity was upgraded in the presence of Ag⁺, Ca²⁺ and Sr²⁺, but was totally suppressed by 5 mM phenylmethylsulfonyl fluoride, which suggests that this enzyme belongs to the serine protease family. L9^T protease was resistant to certain common organic solvents and surfactants; particularly, 5 mM Tween 20 and Tween 80 improved the activity by 63 and 15%, respectively. More importantly, L9^T protease was found to be effective in dehairing of goatskins, cowhides and rabbit-skins without damaging the collagen fibers. These properties confirm the feasibility of L9^T protease in industrial applications, especially in leather processing.

• Food Science of Animal Resources
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• v.44 no.4
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• pp.912-933
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• 2024

The objective of this study was to isolate, identify, and evaluate novel Korean starter cultures for use in fermented sausages. A total of 72 strains were isolated from various indigenous sources, including Nuruk, Jeotgal, and mudflats on the west coast of South Korea. Two strains were identified as Penicillium nalgiovense (SD01 and SJ02), a traditional starter used in the production of fermented sausages. A comparative analysis was performed between SD01 and SJ02 using the commercial starter culture (M600). Strain SJ02 exhibited superior lipolytic and proteolytic activities, as well as an enhanced growth rate at the optimal salinity level of 2% NaCl compared to M600. No significant differences were observed in thiobarbituric acid reactive substances values, sausage colors, and texture properties between SJ02 and M600 fermented sausages, except for adhesiveness. Profiles of mycotoxin-related genes were similar for both strains. Electronic nose analysis revealed distinct aroma profiles between SJ02 and M600 fermented sausages, with a relatively higher levels of propan-2-one and butyl butanoate in SJ02, and a higher level of ethanol and propanal in M600. In electronic tongue analysis, there was no significant differences in taste characteristics between SJ02 and M600. These results indicate that P. nalgiovense SJ02 is a potential starter culture to produce dry fermented sausages, enhancing Korean style cured meat processing industry.

• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.1
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• pp.97-106
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• 1984

The Antarctic krill, Euphausia superba, is drawing attention over the world as the largest source of unutilized proteins in the ocean. For the use of krill as a human food, processing conditions of krill sauce by autolysis and/or commercial proteolytic enzyme digestion were examined. The krill was chopped and mixed with equal weight of water, and hydrolyzed by autolysis and/or commercial proteolytic enzyme digestion. The optimal conditions for hydrolysis of krill were $52.5^{\circ}C$, pH 7.0-7.5, 3 hours by autolysis, $52.5^{\circ}C$, pH 6.3, 3hours by bromelain (0.5 %) digestion, and $52.5^{\circ}C$, pH 7.0-7.5, 3 hours by commercial complex enzyme (5 %) digestion, respectively The maximum hydrolyzing rate of protein were 83.2 % by autolysis, 89.7 % by bromelain digestion, 92.7 % by commercial complex enzyme digestion. After krill meat hydrolyzed by autolysis at optimum condition, inactivated at $100^{\circ}C$ for 20 minutes and filtered with Buchner funnel. Two kinds of products were prepared with krill hydrolysate and preservatives: one contained 10 % of sodium chloride and 0.06 % of benzoic acid and the other 10 % of sodium chloride and 3 % of ethyl alcohol. These products were filled in the sterilized glass bottle and sealed. The pH, volatile basic nitrogen, amino nitrogen, color value (L, a and b values) and viable counts of bacteria were determined during storage at $37^{\circ}C$. The results showed that the products could be preserved in good condition during one month at $37^{\circ}C$. As a method to reduce the sodium level in krill sauce, it is convinced that sodium chloride could be replaced half in partially by potassium chloride. In the products prepared from krill by autolysis, bromelain or commercial complex enzyme digestion, hypoxanthine and 5'-IMP were abundant among the nucleotides and their related compounds as 15.3-20.4 ${\mu}mole/g$, dry solid, 2.2-2.5 ${\mu}mole/g$, dry solid, respectively. The abundant free amino acids were lysine, leucine, proline, alanine and valine. The contents of these amino acids were 67.4 %, 69.4 %, 69.8 % of the total free amino acids of each products. And TMAO, betaine and total creatinine were low in contents. The flavor of krill sauce prepared from krill by autolysis or enzyme digestion was not inferior to that of traditional Kerean soy sauce by sensory evaluation.

• Journal of Food Hygiene and Safety
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• v.14 no.4
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• pp.346-351
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• 1999

To develop a lactic starter to produce antimicrobial substance for inhibiting the growth of a variety of foodborne spoilage bacteria in fermented foods, we investigated the anti-bacterial effect of the antibacterial substance, produced by Lactobacillus amylovorus IMC-1, against foodborne spoilage strains, and its sensitivity on the treatment of proteolytic enzymes. L. amylovorus IMC-1, which was isolated from a traditional cheese in Inner Mongolia, produced a maximum amount of antibacterial substance in the skim milk medium after 72 h incubation at 37$^{\circ}C$, and further incubation resulted in the same activity. The substance obtained from gel filtration inhibited all strains used such as Bacillus subtilis IFO 3025, Staphylococcus aureus IAM 1011, Listeria monocytogenes VTU 206, Escherichia coli RB, and Pseudomonas fragi IFO 3458 at the concentration of 20 units/ml. This substance was found to show bactericidal action against B. subtilis, E. coli, and Ps. fragi, and bacteriostatic activity against both Staph. aureus and L. monocytogenes. The bactericidal action was due to cellular Iysis. The substance is not organic acid, hydrogen peroxide and proteinaceous compound.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.23 no.2
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• pp.109-124
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• 1990

A rapid processing method for fish sauce of high quality stability and favorable flavor was investigated using mackerel waste as starting material. The chopped waste was homogenized with water and hydrolyzed by commercial proteolytic enzymes such as Complex enzyme-2000($2.18\cdot10^4$ U/g solid, Pacific Chem. Co.) and Alcalase ($1.94\cdot10^4$ U/g solid, Novo) in a cylindrical vessel with 4 baffles and 6-bladed turbine impeller. Optimal pH and temperature for the hydrolysis with Complex enzyme-2000 were 8.0 and $50^{\circ}C$, and those with Alcalase were 9.0 and $55^{\circ}C$. In both cases, the reasonabe amount of added water and enzyme concentration based on the waste weight were $40\%,\;3\%$ and hydrolyzing time was 100 min. Thermal treatment of the hydrolysate with $6\%$ of invert sugar for 2 hours at $90^{\circ}C$ was adequated to inactivation of the enzymes and pasteurization of the hydrolysate. Flavor, taste and color of the hydrolysate were improved during the thermal treatment in which the browning reaction products might participate and result in antioxidative and bactericidal effects. Combined use of $0.005\%$ of Caryophylli flos with $6\%$ of invert sugar was also effective for the improvement of taste. Yield of the fish sauce based on the total nitrogen of the raw waste was $93.7\~94.9\%$, and $87.6\~87.9\%$ of the total nitrogen in the fish sauce was in the from of amino nitrogen. The pH, salinity and histamine content of the fish sauce prepared with $15\%$ of table salt were $6.1\~6.2$, $14.0\~14.5\%$ and less than $10mg\%$, respectively. The fish sauce was stable on bacterial growth during the storage of 60 days at $26\pm3^{\circ}C$ and the quality was also maintained.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.23 no.5
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• pp.361-372
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• 1990

Processing conditions of whole sardine into modified fish sauce were investigated. Thawed and chopped sardine was homogenized and hydrolyzed using commercial proteolytic enzymes such as complex enzyme-2000($2.18{\cdot}10^4U/g solid$) and alcalase($1.94{\cdot}10^4\;U/g solid$) in a cylindrical vessel with 4 baffles and 6-bladed impeller. Optimal pH, enzyme concentration and temperature for the hydrolysis with complex enzyme-2000 were 7.0, $7\%$ (W/W) and $52^{\circ}C$, and-those with alcalase were 8.0, $6\%$ (W/W) and $60^{\circ}C$. In both cases, the reasonable amount of water for homogenization, agitation speed and hydrolyzing time were $100\%$ (W/W), 100 rpm and 210 minutes. Thermal treatment of the filtered hydrolysate at $90^{\circ}C$ for 2 hours with $6\%$ of invert sugar was adequated to inactivation of the enzymes and pasteurization of the hydrolysate. Flavor, taste and color of the hydrolysate were improved during the heating process in which the browning products might participate. The content of free amino nitrogen in the fish sauce seasoned with $15\%$ of table salt was ca. $1,640 mg\%$. Yield of the fish sauce based on the contents of proteinous and free amino nitrogen in the raw whole sardine was ca. $86\%$, and ca. $96\%$ of these compounds of the fish sauce was in the form of free amino nitrogen. The pH, salinity and histamine content of the fish sauce were $6.1\~6.3,\;14.2\~14.3\%$ and less than $10\;mg\%$.