• Fisheries and Aquatic Sciences
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• v.7 no.1
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• pp.10-15
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• 2004

A total of 52 pathogenic Vibrio strains was isolated from the Gwangan Beach during summer in 2003. The isolated vibrios were composed of 6 different species: V. parahaemolyticus, V. cholerae non O1, V. fluvialis, V. vulnificus, V. alginolyticus, and V. mimicus. V. parahaemolyticus was most predominant as $46\%$ (24/52), V. cholerae non O1 was the second with $23\%$ (12/52), and V. fluvialis was the third with $17\%$ (9/52). Among the isolated strains, 22 strains showed hemolytic, proteolytic or ureolytic activity. Eight strains showed both hemolysin and protease activities, and either 6 strains showed only hemolysin activities and 7 strains only protease activities. Only one strain of V. parahaemolyticus isolates showed urease activity. The urease-positive V. parahaemolyticus strain (V. parahaemolyticus S25) showed the same biochemical characteristics as the reference strain, V. parahaemolyticus KCTC 2471 (urease­negative) except for urease production. To compare the degree of virulence of Vibrio strains having different pathogenic factors, hemolysin, protease, or urease-positive strains were injected into groups of 10 each of ICR mice (7- to l0-week-old male). The lethal rate of urease-positive V. parahaemolyticus S25 was significantly high, being $70\%$. Protease-positive strains showed $40-60\%$ of lethal rate. Hemolysin-positive strains showed no mortality, similar to non-pathogenic V. parahaemolyticus KCTC 2471 and V. parahaemolyticus FM12.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.4
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• pp.369-375
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• 2018

This study investigated the effects of selected seaweeds on rice koji preparation (rice inoculated with Aspergillus luchuensis) and enzyme activity. Four types of rice koji were prepared using one of three seaweeds (0.5% laver, 0.5% kelp and 0.5% green laver) or a control for 72 h. The changes in the moisture content, water activity, pH, total mold cell count, amylase and protease activities were measured. During preparation, there was no significant difference in the moisture content among the four kojis, whereas the pH in the kojis made with either laver or green laver decreased rapidly compared with the control (P<0.05). This seemed to result from the seaweeds promoting the growth of mold cells. In terms of the activities of both amylase and protease, the koji with laver was superior. Subsequently, the amylase and protease activities of the koji made with laver were evaluated at various pHs (3 to 9), temperatures ($15-55^{\circ}C$) and NaCl concentrations (0-10%). The activities of both enzymes decreased notably at pH 9 and the protease activity decreased at temperatures above $45^{\circ}C$. Although the activities of both enzymes decreased at greater than 2.5% NaCl, activity was present at 10% NaCl.

• International journal of advanced smart convergence
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• v.10 no.1
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• pp.197-208
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• 2021

The deer antler has been used as a major drug in oriental medicine for a long time. Recently, the demand for easy-to-take health functional foods is increasing due to economic development and changes in diet. As part of research on the development of functional materials for antlers, lactic acid fermentation of antler extract was performed. It was intended to develop a functional material with enhanced total polyphenol and flavonoid content and enhanced antioxidant activity. Lactic acid bacteria fermentation was performed by adding 4 types of lactic acid bacteria starter products, B. longum, Lb. Plantarum, Lb. acidophilus and mixture of 8 types of lactic acid bacteria to the antler water extract substrate, respectively. During the fermentation of lactic acid bacteria, the number of proliferation, total polyphenol and total flavonoid content, DPPH radical scavenging and antioxidant activity were quantified and evaluated. As a result of adding these four types of lactic acid bacteria to the antler water extract substrate, the number of lactic acid bacteria measured was 2.04~5.00×107. Meanwhile, a protease (Baciullus amyloliquefaciens culture: Maxazyme NNP DS) was added to the antler extract to decompose the peptide bonds of the contained proteins. Then, these four types of lactic acid bacteria were added and the number of lactic acid bacteria increased to 2.84×107 ~ 2.21×108 as the result of culture. The total polyphenol contents were 4.82~6.26 ㎍/mL in the lactic acid bacteria fermentation extracts, and after the reaction of protease enzyme and lactic fermentation, increased to 14.27~20.58 ㎍/mL. The total flavonoid contents were 1.52~2.21 ㎍/ml in the lactic acid bacteria fermentation extracts, and after the protease reaction and fermentation, increased to 5.59 ~ 8.11 mg/mL. DPPH radical scavenging activities of lactic acid bacteria fermentation extracts was 17.03~22.75%, but after the protease reaction and fermentation, remarkably increased to 32.82~42.90%.

• Animal Bioscience
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• v.35 no.10
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• pp.1628-1634
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• 2022

Objective: This study focused on the effect of dietary metallo-protease and Bacillus velezensis CE 100 on growth performance, carcass parameters, intestinal microflora, footpad dermatitis (FPD), and manure odor in broiler chickens. Methods: One hundred-ten (two-day-old Ross 308) broiler chicks were randomly assigned to five groups with two replicate pens. The dietary treatments were divided to control, metallo-protease groups (A1, added with 0.1%; A2, added with 0.2%) and B. velezensis CE 100 groups (B1, added with 0.5%; B2, added with 1.0%). Results: The feed intake was decreased in A1 and B2 compared to the other group (p<0.05). The liver weight was lower in B2 than in A2 (p<0.05). The Salmonella in the cecum was decreased in A2 compared to control and A1 (p<0.05). However, the lactic acid bacteria were increased in all treatments (p<0.05). The litter moisture content was decreased in A2, B1, and B2 (p<0.05). The litter quality visual score was increased in all treatments (p<0.05). The FPD score and prevalence were reduced in all treatments (p<0.05). The (CH₃)₂S emission was decreased in all treatments (p<0.05). Conclusion: The present study indicated that both additives improve litter quality and reduce the incidence of FPD. These findings suggest that dietary metallo-protease and B. velezensis CE 100 have the potential to improve the broiler chickens' welfare.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.3
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• pp.364-370
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• 2008

Chemical analysis and in vitro studies were conducted to investigate the nutritive value for ruminants of cell mass from lysine production (CMLP) which is a by-product of the lysine manufacturing process. Proximate analysis, protein fractionation, and in vitro protein degradation using protease from Streptomyces griseus and strained ruminal fluid were carried out to estimate ruminal protein degradability of CMLP with two reference feedstuffs-soybean meal (SBM) and fish meal (FM). Amino acid composition and pepsin-HCl degradability were also determined to evaluate postruminal availability. CMLP contained 67.8% crude protein with a major portion being soluble form (45.4% CP) which was composed of mainly ammonium nitrogen (81.8% soluble CP). The amount of nucleic acids was low (1.15% DM). The total amount of amino acids contained in CMLP was 40.60% DM, which was lower than SBM (47.69% DM) or FM (54.08% DM). CMLP was composed of mainly fraction A and fraction B2, while the protein fraction in SBM was mostly B2 and FM contained high proportions of B2 and B3 fractions. The proportion of B3 fraction, slowly degradable protein, in CP was the highest in fish meal (23.34%), followed by CMLP (7.68%) and SBM (1.46%). CMLP was degraded up to 51.40% at 18 h of incubation with Streptomyces protease, which was low compared to FM (55.23%) and SBM (83.01%). This may be due to the insoluble portion of CMLP protein being hardly degradable by the protease. The in vitro fermentation by strained ruminal fluid showed that the amount of soluble fraction was larger in CMLP (40.6%) than in SBM (17.8%). However, because the degradation rate constant of the potentially degradable fraction of CMLP (2.0%/h) was lower than that of SBM (5.8%/h), the effective ruminal protein degradability of CMLP (46.95%) was slightly lower than SBM (53.77%). Unavailable fraction in the rumen was higher in CMLP (34.0%) compared to SBM (8.8%). In vitro CP degradability of CMLP by pepsin was 80.37%, which was lower than SBM (94.42%) and FM (89.04%). The evaluation of protein degradability using different approaches indicated that soluble protein in CMLP may supply a large amount of ammonia in the rumen while insoluble protein can be by-passed from microbial attacks due to its low degradability. The results from this study suggest that CMLP can be used as a protein supplement to ruminants for supplying both non-protein nitrogen to rumen microbes and rumen undegradable protein to the host animal.

• Journal of Life Science
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• v.6 no.4
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• pp.270-277
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• 1996

Streptococcus sp J-C1 producing bacteriocin was isolated from Kimchi. The optimum conditions for bacteriocin production by Streptococcus sp. J-C1 were evaluated. For the maximum yield of bacteriocin production by Streptococcus sp. J-C1, the cell should be harvested at the late stationary phase and the temperature, pH and NaCl concentration should be 25$\circ$C, pH 8 and without the addition of NaCl, respectively. Sucrose should be used as a carbon source and organic nitrogen such as peptone should be used as a nitorgen source for the best yield. The production of bacteriocin is related to the cell growth of Streptococcus sp. J-C1. The bacteriocin from Streptococcus sp. J-C1 was active for gram positive microorganisms such as Lactobacillus sp., Leuconoctoc sp., Lactococcus sp., Streptococcus mutans, Staphylococcus aureus amd Bacillus subtilis and also active for gram negetive bacteria such as Acetobacter aceti. Antibacterial activity of the bacteriocin was completely disappeared by protease treatment.

• Journal of Microbiology
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• v.42 no.2
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• pp.156-159
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• 2004

In general, the salinity of the ocean is close to 3.5％ and marine vibrios possess the respiratory chain-linked Na$\^$+/ pump. The influence of sodium chloride and the proton conductor carbonylcyanide m-chlo-rophenylhydrazone (CCCP) on the production of extracellular proteases in a marine Vibrio strain was examined. At the concentration of 0.5 M, sodium chloride minimally inhibited the activity of extra-cellular proteases by approximately 16％, whereas at the same concentration, the producton of extra-cellular proteases was severely inhibited. On the other hand, the production of extracellular proteases was completely inhibited by the addition of 2 ${\mu}$M CCCP at pH 8.5, where the respiratory chain-linked Na$\^$+/ pump functions.

• KSBB Journal
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• v.27 no.6
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• pp.352-360
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• 2012

Bacillus clausii I-52 which produced SDS- and $H_2O_2$-tolerant extracellular alkaline protease (BCAP) was isolated from heavily polluted tidal mud flat of West Sea in Incheon, Korea and stable strain (transformant C5) of B. clausii I-52 harboring another copy of BCAP gene in the chromosome was developed using the chromosome integration vector, pHPS9-fuBCAP. When investigated the production of BCAP using B. clausii transformant C5 through pilot-scale submerged fermentation (500 L) at $37^{\circ}C$ for 30 h with an aeration rate of 1 vvm and agitation rate of 250 rpm, protease yield of approximately 105,700 U/mL was achieved using an optimized medium (soybean meal 2%, wheat flour 1%, sodium citrate 0.5%, $K_2HPO_4$ 0.4%, $Na_2HPO_4$ 0.1%, NaCl 0.4%, $MgSO_4{\cdot}7H_2O$ 0.01%, $FeSO_4{\cdot}7H_2O$ 0.05%, liquid maltose 2.5%, $Na_2CO_3$ 0.6%). The enzyme stability of BCAP was increased by addition of polyols (10%, v/v) and also, the stabilities of BCAP towards not only the thermal-induced inactivation at $50^{\circ}C$ but also the SDS and $H_2O_2$-induced inactivation at $50^{\circ}C$ were enhanced. Among the polyols examined, the best result was obtained with propylene glycol (10%, v/v). The BCAP supplemented with propylene glycol exhibited extreme stability against not only the detergent components such as ${\alpha}$-orephin sulfonate (AOS) and zeolite but also the commercial detergent preparations. The granulized enzyme of BCAP was prepared with approximately 1,310,000 U/g of granule. Wash performance analysis using EMPA test fabrics revealed that BCAP granule exhibited high efficiency for removal of protein stains in the presence of anionic surfactants as well as bleaching agents. When compared to Savinase 6T$^{(R)}$ and Everlase 6T$^{(R)}$ manufactured by Novozymes, BCAP under this study probably showed similar or higher efficiency for the removal of protein stains. These results suggest that the alkaline protease produced from B. clausii transformant C5 showing high stability against detergents and high wash performance has significant potential and a promising candidate for use as a detergent additive.

• Korean Journal of Food Science and Technology
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• v.30 no.6
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• pp.1333-1338
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• 1998

Several enzymes of kimchi ingredients were assayed to improve the product quality using these quality related enzyme information. Among various hydrolases, amylase and protease were selected with respect to lactic acid fermentation. Peroxidase and ascorbic acid oxidase were studied for off flavor production and ascorbic acid destruction. The amount of protein in kimchi ingredients, specific and total enzyme activity of sample were compared. Regarding total enzyme activity of sample, ${\alpha}-amylase$ activity of salted and fermented anchovy, dried red pepper and salted and fermented shrimp were higher than other ingredients. Activity of salted and fermented anchovy was 2,790.0 units/g sample. Salted and fermented anchovy, oyster and Chinese radish showed the highest ${\beta}-amylase$ activity (4.4, 2.1, 1.0 units/g sample, respectively). Salted and fermented anchovy showed the highest protease activity of 13.4 PU/g sample, followed by salted and fermented shrimp and dried red pepper. For peroxidase, Chinese radish, cucumber, green onion showed the highest activity of 7.2, 6.8 and 5.6 units/g sample, respectively. In case of ascorbic acid oxidase, salted and fermented anchovy showed the strongest enzyme activity (331.4 units/g sample), followed by dried red pepper and salted and fermented shrimp.

• Korean Journal of Food Science and Technology
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• v.34 no.1
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• pp.57-64
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• 2002

This study was carried out to investigate the effect of yucca extract on the flavor development in Chungkookjang fermented by Bacrillus sp. b01. The changes in the contents of amino-type N, ammonia type N, volatile compounds and organic acids, and those in the activities of ${\alpha}-amylase$ and protease were also determined with aging period. The amount of amino-type N increased gradually with time and was slightly higher in Chungkookjang containing yucca extract than in control. The content of ammonia-type N in Chungkookjang decreased by the addition of yucca extract. During aging, a little higher amylase activity was detected in Chungkookjang containing yucca extract. However, the amylase activity was the lowest in Chungkookjang containing 1 mg/g of yucca extract. The protease activity was slightly higher in Chungkookjang containing yucca extract. The organic acids, such as citrate, acetate, malate, fumarate, and succinate, were detected. The yucca extract reduced the production of tetramethylpyrazine which was responsible for the unpleasant odor, but enhanced the production of 2,5-dimethylpyrazine and 2,6-dimethylpyrazine which contributed to the taste. Sensory evaluation showed that the addition of yucca extract of 0.5 mg/g significantly improved the flavor and taste of products.