• Korean Journal of Veterinary Service
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• v.20 no.3
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• pp.261-279
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• 1997

The study for a effect of monitoring on bovine mastitis was conduced for improvement of raw milk from Jan. to Dec. in 1996. Sampling the milk of 367 cows(1, 406 quarters) from 5 herds in Inchon and were carried out California mastitis test(CMT), somatic cell count(SCC), isolation of pathogens and antibiotic sensitivity tests. The results were summarized as follows, 1. The number of bovine mastitis was 177 cows(48.2%) and 371 quarters(26.4%) : clinical mastitis : 25 cows(6.8%), 32 quarters(2.3%) and subclinicsl mastitis : 152 cows(41.4% ), 339 quarters(24.1%). Incidence rate of mastitis by season were Summer 52.0%, Fall and Winter 48% and Spring 41%. Incidence rate of mastitis by quarters were Summer 30%, Fall 28%, Winter 25% and Spring 21%, respectively. 2. In the distribution of CMT degree by quarter, CMT positive(CMT$\pm$) of 1, 406 quarters milk were 50.1% (704 quarters). The ratio of CMT positivity by quarter were left front quarter 55.8%, right front quarter 48.9%, right hind quarter 48.6% and left hind quarter 47% The ratio of CMT positivity by season were Summer 54.1%, Fall 49.7%, Spring 48.5% and Winter 48% 3. The highest mean SCC by season among 5 herds was "A" herd. Mean SCC (cell/ml) of A herd were Summer 2, 032, 000cells/ml, Fall 1, 109, 000cells/ml, Winter 782, 000cells/ml and Spring 577, 000cells/ml. The lowest mean SCC by season among 5 herds was "E" herds. Mean SCC of E herd were Summer 1, 064, 000cells/ml, Spring 795, 000cells/m1, Fall 429, 000cells/ml and Winter 400, 000cells/ml. Mean SCC of the other herds by season were little difference. 4. The milk samples of "A" herd were collected from 10 cows. In 3 seasons, mean SCC of No. 2 and 3 cows were than 1, 000, 000cells/ml. In 1 season, mean SCC of No. 6, 7 and 8 cows were than 1, 000, 000cells/ml. The more than mean SCC 1, 000, 000cells/ml of cows by season were distributed Summer 4 cows, Winter 3 cows, Spring and Fall 1 cow respectively. The milk samples of "B" herd were collected from 14 cows. In 3 seasons, mean SCC of No. 1 cow was more than 1, 000, 000cells/ml. In 2 seasons, mean SCC of No. 5, 9 and 14 cows were more than 1, 000, 000cells/ml. In 1 season, No. 3, 6 and 7 cows were more than 1, 000, 000cells/ml. The more than mean SCC 1, 000, 000cells/ml of cows by season were distributed Fall and Winter 4 cows respectively, Summer 3 cows and Spring 1 cow. The milk samples of "C" herd were collected from 18 cows. In 2 seasons, mean SCC of No. 16 cow was more than 1, 000, 000cells/ml. In 1 season, mean SCC of No. 1, 2, 6, 7, 13, 15 and 18 cows were more than 1, 000, 000cells/ml respectively. The more than mean SCC 1, 000, 000cells/ml of cows by season were distributed Summer 5 cows, Fall 3 cows, Spring 2 cows and Winter 1 COW. The milk sampes of "D" herd were collected 24 cows. In 3 season, mean SCC of No. 14 cow was more than 1, 000, 000cells/ml. In 2 seasons, mean SCC of No. 14 and 18 cows were more than 1, 000, 000cells/ml. In 1 season, mean SCC of No. 1, 2, 3, 8, 12, 17, 19, 20 and 21 cows were more than 1, 000, 000cells/ml. The more than mean SCC 1, 000, 000cells/ml of cows were distributed Fall 15 cows, Spring and Winter 4 cows respectively and Summer 3 cows. The milk samples of "E" herd were collected from 27 cows. In 2 seasons, mean SCC of No. 6, 7 and 21 cows were more than 1, 000, 000cells/ml. In 1 season, mean SCC of No. 2, 4, 7, 11, 14, 16 and 23 cows were more than 1, 000, 000cells/ml. The more than mean SCC 1, 000, 000cells/ml of cows were distributed Spring and Fall 5 cows respectively, Summer and Winter 2 cows, respectively. 5. The rate of isolated pathogenic microorganisms from bovine mastitis were summarized as follows : Staphylococcus sp 168 strains(45.8%), Streptococcus sp 82 strains(22.3%), Gram(-) sp 45 strains(12.3%), Gram(＋) sp 51 strains and the other sp 21 strains(5.7%). 6. The highest of antibiotic sensitivity test of each microorganism was summarized as follows : Staphyolcoccus sp - cephalosporin 76%, gentamicin 55%, Streptococcus sp - ampicillin 61%, cephalosporin 63%, Gram(-) sp - gentamicin 58%, Gram(＋) sp - cephalosporin 63%, The other sp - cephalosporin 90%. Microorganisms showed the highest sensitivity(68%) to cephalospsorin. Microorganisms showed the highest sensitivity(68%) to cephalospsorin.

• Journal of Life Science
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• v.25 no.6
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• pp.680-685
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• 2015

Previously, cellulase and xylanase producing microorganism, Bacillus subtilis NC1, was isolated from soil. Based on the 16S rRNA gene sequence and API 50 CHL test the strain was identified as Bacillus subtilis, and named as B. subtilis NC1. We cloned and sequenced the genes for cellulase and xylanase. Plus, the deduced amino acid sequences from the genes of cellulase and xylanase were determined and were also identified as glycosyl hydrolases family (GH) 5 and 30, respectively. In this study to optimize the medium parameters for cellulase production by B. subtilis NC1 the RSM (response surface methodology) based on CCD (central composite design) model was performed. Three factors, tryptone, yeast extract, and NaCl, for N or C source were investigated. The cellulase activity was measured with a carboxylmethyl cellulose (CMC) plate and the 3,5-dinitrosalicylic acid (DNS) methods. The coefficient of determination (R²) for the model was 0.960, and the probability value (p=0.0001) of the regression model was highly significant. Based on the RSM, the optimum conditions for cellulase production by B. subtilis NC1 were predicted to be tryptone of 2.5%, yeast extract of 0.5%, and NaCl of 1.0%. Through the model verification, cellulase activity of Bacillus subtilis NC1 increased from 0.5 to 0.62 U/ml (24%) compared to the original medium.

• Journal of Life Science
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• v.25 no.2
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• pp.237-242
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• 2015

The use of calcite-forming bacteria (CFB) in crack remediation and durability improvements in construction materials creates a permanent and environmentally-friendly material. Therefore, research into this type of application is stimulating interdisciplinary studies between microbiology and architectural engineering. However, the mechanisms giving rise to these materials are dependent on calcite precipitation by the metabolism of the CFB, which raises concerns about possible hazards to cement-based construction due to microbial metabolic acid production. The aim of this study was to determine target microorganisms that possibly can have bio-corrosive effects on cement mortar and to assess multi-functional CFBs for their safe application to cement structures. The chalky test was first used to evaluate the $CaCO_3$ solubilization feature of construction sites by fungi, yeast, bacterial strains. Not all bacterial strains are able to solubilize $CaCO_3$, but C. sphaerospermum KNUC253 or P. prolifica KNUC263 showed $CaCO_3$ solubilization activity. Therefore, these two strains were identified as target microorganisms that require control in cement structures. The registered patented strains Bacillus aryabhatti KNUC205, Arthrobacter nicotianae KNUC2100, B. thuringiensis KNUC2103 and Stenotrophomonas maltophilia KNUC2106, reported as multifunctional CFB (fungal growth inhibition, crack remediation, and water permeability reduction of cement surfaces) and isolated from Dokdo or construction site were unable to solubilize $CaCO_3$. Notably, B. aryabhatti KNUC205 and A. nicotianae KNUC2100 could not hydrolyze cellulose or protein, which can be the major constituent macromolecules of internal materials for buildings. These results show that several reported multi-functional CFB can be applied to cement structures or diverse building environments without corrosive or bio-deteriorative risks.

• Journal of Life Science
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• v.19 no.8
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• pp.1039-1046
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• 2009

The cytochrome P450s (P450s) metabolizing natural products are among the most versatile biological catalysts known in plants, but knowledge of the structural basis for their broad substrate specificity has been limited. The activity of p-coumarate 3-hydroxylase (C3H) is thought to be essential for the biosynthesis of lignin and many other phenylpropanoid pathway products in plants however, all attempts to express and purify the protein corresponding C3H gene have failed. As a result, no conditions suitable for the unambiguous assay of the enzyme are known. The detailed understanding of the mechanism and substrate-specificity of C3Hdemands a method for the production of active protein on the milligram scale. We have developed a bacterial expression and purification system for the plant C3H, which allows for the quick expression and purification of active wild-type C3H via introduction of combinational mutagenesis. The modified cytochrome P450 C3H ($C3H_{mod}$) could be purified in the absence of detergent using immobilized metal affinity chromatography and size exclusion chromatography following extraction from isolated membranes in a high salt buffer and catalytically activated. This method makes the use of isotopic labeling of C3H for NMRstudies and X-ray crystallography practical, and is also applicable to other plant cytochrome P450 proteins.

• Journal of Life Science
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• v.20 no.3
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• pp.430-436
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• 2010

In this study, the effects of dibenzocyclooctadiene on seed germination were investigated in pepper. Four $C_{18}$ dibenzocyclooctadiene lignans - schisandrin (1143.7 mg), schisandrin C (317.3 mg), gomisin A (261.4 mg) and gomisin N (213.4 mg) - were isolated from hexane extracts of the fruits of Schisandra chinensis. The molecular structures of the four lignans were elucidated based on spectroscopic analyses including 1D NMR experiments, and bi comparing their spectroscopic data with those of previous literatures. Seeds were immersed in $10^{-5}\;M$ schisandrin, $10^{-6}\;M$ schisandrin C and $10^{-7}\;M$ gomisin A and gomisin N for 1 hr and incubated at $25^{\circ}C$ in the dark for germination. Compared to untreated control, treatment with schisandrin C and gomisin A suppressed seed germination at 48 hrs after incubation, whereas treatment with gomisin N increased germination rate at 48 hrs after incubation. The results of the germination activity of the lignans from S. chinensis confirm their potential plant growth role, and the relative natural abundances of these metabolites suggest their potential use as natural plant growth regulators.

• Journal of Life Science
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• v.24 no.3
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• pp.252-259
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• 2014

The leaves of Peatasites japonicus are a traditional oriental medicine with diverse biological activities. A simple and specific analytical method for the quantitative determination of bakkenolide B constituents from methanolic extract of the leaves of P. japonicus was developed. Bakkenolide B was isolated from the leaves of P. japonicus, and its structure was elucidated based on 1D, 2D NMR, and GC-MS spectral data. A liquid chromatographic method was developed to evaluate the quality of P. japonicus through determination of major active compound, bakkenolide B. The wavelengths at 254 and 215 nm were chosen to determine bakkenolide B. The recovery of the method was in the range of 98.6 to 103.1%, and bakkenolide B showed good linearity ($r^2$=0.999) within test ranges. The developed method was applied to the determination of bakkenolide B in the plant part and seasonal changes. The results showed that the content of bakkenolide B in the leaf was higher than in the petiole and rhizome. In this study, a simple, rapid, and reliable high-performance liquid chromatography method was used to determine the percentage and composition of bakkenolide B in P. japonicus procured from different Petasites species plants in South Korea. The method can be employed in routine quantitative analysis and quality control of different products in the market.

• Journal of Life Science
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• v.24 no.3
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• pp.242-251
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• 2014

The objective of this study was to isolate a photosensitizer from Pueraria thunbergiana leaves that induces apoptosis in SK-HEP-1 cells. Column chromatography and thin layer chromatography were used to isolate active compounds from extracts of P. thunbergiana leaves. The structures of the isolated compounds were determined by 1D-NMR, 2D-NMR, and FAB-mass spectroscopy. A substance, named M4-3, was purified from the leaves of P. thunbergiana using various chromatography methods, and the absorbance of the substance was measured. The absorbance was highest at 410 nm, suggesting that the M4-3 substance was a different compound from chlorophyll a and b, which absorb at 410, 502, 533, and 607 nm. Further analyses revealed that the M4-3 compound was a $13^2$-hydoxy pheophorbide, a methyl ester with a molecular weight of 662. M4-3 was identified as a derivative compound of pheophorbide, with a structure that magnesium comes away from the porphyrin ring. The results of the analysis of the cytotoxicity of the M4-3 substance against the SK-HEP-1 cells revealed that it inhibited rates of cell growth by 40% and 80% at a concentration of 0.04 ${\mu}M$ and 0.08 ${\mu}M$, respectively. The M4-3 compound was found to be a photosensitizer for cytotoxicity because it was appeared only in light condition as examining activity in different irradiation conditions (light condition and nonlight condition) under the same concentration. Analysis of morphological changes in the cells following cell death induced by exposure to the M4-3 substance reveled representative phenomena of apoptosis (nuclear condensation, vesicle formation, and fragmentation of DNA). The induction of apoptosis was attributed to the compound's photodynamic activity.

• Journal of Life Science
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• v.23 no.3
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• pp.415-425
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• 2013

This study compared the characteristics of five Bacillus strains capable of aerobic and anaerobic growth, CBW3, CBW4, CBW9, CBW14 and EBW10. They were isolated and selected from a polychaete, Perinereis aibuhitensis, which is known as a good degrader of organic compounds in marine wetland. Based on a 16S rRNA sequence, CBW3 and CBW14 were found to share more than 99.8% similarity with B. nanhaiensis, B. arsenicus and B. barbaricus. CBW4, CBW9 and EBW10 shared 92.7%, 99.8%, and 99.8% similarity with B. anthracis, B. algicoa and B. thuringiensis, respectively. The temperature, salinity, and pH ranges of the cell growth of the Bacillus strains were $4-45^{\circ}C$, 0-17%, and pH 5-pH 9, respectively. All Bacillus strains were found to exhibit enzyme activities for the degradation of casein and starch. Notably, strain EBW10 exhibited the enzyme activities for all the tested macromolecules, DNA, casein, starch, cellulose, and four kinds of Tweens, which suggests the possibility that it had protease, amylase, cellulose, and lipase. All five Bacillus strains had alkaline phosphatase activities, and the strains CBW3, CBW4, and EBW10 also had acid phospatase. Strains CBW3 and EBW10 exhibited the enzyme activities both for esterase (C4) and esterase lipase (C8). The analysis of fatty acids revealed that in all strains, major fatty acids were anteiso $C_{15:0}$ and iso $C_{15:0}$.

• Journal of Life Science
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• v.23 no.3
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• pp.389-398
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• 2013

Platycodin D is a major constituent of triterpene saponins, which is found in the root of Platycodon grandiflorum, Platycodi Radix, which is widely used in traditional Oriental medicine for the treatment of many chronic inflammatory diseases. Several pharmacological effects of this compound have been reported recently, such as anti-inflammation, immunogenicity, anti-adipogenesis, lowered cholesterol, and anti-cancer activity. However, the mechanism by which this action occurs is poorly understood. In this study, we found that platycodin D greatly increased the potential of the anti-proliferative effect in various cancer cell lines. Our data revealed that platycodin D treatment resulted in a time- and concentration-response growth inhibition of U937 cells by inducing apoptosis, as evidenced by the formation of apoptotic bodies, chromatin condensation, and the accumulation of cells in the sub-G1 phase. Apoptosis induction of U937 cells by platycodin D correlated with an increase in the Bax/Bcl-2 ratio and caused the down-regulation of IAP family members. In addition, platycodin D treatment resulted in proteolytic activation of caspase-3, the concomitant degradation of poly(ADP-ribose) polymerases, and the collapse of the mitochondria membrane potential (${\Delta}{\Psi}_m$). However, the cytotoxic effects induced by platycodin D treatment were significantly inhibited by z-DEVD-fmk, a caspase-3 inhibitor, which demonstrated the important role that caspase-3 played in the observed cytotoxic effect. These findings suggest that platycodin D may be a potential chemotherapeutic agent for use in the control of human leukemia U937 cells. These findings also provided important new insights into possible molecular mechanisms of the anti-cancer activity of platycodin D.

• Journal of Life Science
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• v.23 no.10
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• pp.1267-1272
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• 2013

The aim of this study was to determine the prevalence and infection status of Salmonella species (spp.) in 25 conventional pig farms by traditional fecal culture and serological methods to develop a Salmonella control program for Korean pig farms. The individual seroprevalence of Salmonella spp. in pigs reared in the 25 pig farms was 83.1% in sows and 6.4-32% in different aged pig groups, with the total seroprevalence 28.4% (141/848). The seroprevalence of the tested pigs increased in accordance with the decrease in maternal antibody and the rearing period on these farms. Of note, all the 25 pig farms contained at least two or more anti-Salmonella antibody-positive sows. In the fecal cultures Salmonella spp. were isolated only in three (12.0%, 3/25) of 16 serologically Salmonella-suspected farms (64.0%, 16/25), showing the limitation of the fecal culture method and the need for serum assays to understand the exact status of Salmonella infection in swine herds, which likely contain subclinically infected pigs or carriers. The results highlight the need to establish a supply system of Salmonella-free gilts for the promotion of a national Salmonella control program on swine farms in Korea. Further studies will be needed to develop an effective monitoring system for the implementation of a national Salmonella control program.