• Microbiology and Biotechnology Letters
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• v.22 no.4
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• pp.340-346
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• 1994

Six bacterial strains capable to grow on medium containing cholesterol as sole carbon source were isolated from soil, pork fat and cheese. Three of them were tentatively identified as Rhodococcus species, Rhodococcus sp. CD-1, R. sp. CD-2, and R. sp. CD-3. All the isolates showed a varying amount of cholest-4-en-3-one as the degradation product, and three strains of Rhodococcus spp. showed rapid degradation of cholesterol. Radioisotopic studies revealed that cholesterol was degraded to non-sterol hydrophilic compounds via cholest-4-en-3-one, and presumably to C0$_{2}$- These strains showed two distinct patterns in further degradation of cholest-4-en-3-one. By one group, R. sp. CD-1 and R. sp. CD-3, cholest-4-en-3-one was rapidly converted to non-sterol inter- mediates without significant accumulation of sterol derivatives in the culture broth. In contrast, by another group, R. sp. CD-2, the substantial amount of cholest-4-en-3-one was accumulated indica- ting a lower conversion of the compound to the next metabolites.

• Korean Journal of Food Science and Technology
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• v.35 no.6
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• pp.1209-1215
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• 2003

This study was carried out to establish a quantitative analysis method of separating immuno-activating substance (EN-SP) from Acanthopanax senticosus (A. senticosus) by competitive direct ELISA. Mouse antiserum (anti-EN-SP) against EN-SP was generated by immunization (s.c.) of EN-SP purified from A. senticosus as an immunogen. The titer of anti-EN-SP was about 1 : 400, and the optimal dilution of EN-SP-HRP conjugate was 1 : 1,000. When the standard curve was constructed by ELISA, its sensitivity was about $0.2{\mu}g/mL$. The coefficient variation of intra- and inter-assay were $6.13{\sim}8.81%$ and $6.73{\sim}8.60%$, respectively. According to the standard curve, the concentration of EN-SP in various senticosus extracts was found to be only $59.85\;{\mu}g$ in 10mg of extract from the bark of A. senticosus. Similarly, the immunostimulating activity to produce $TNF-{\alpha}$ or IL-12 among the various extracts of Acanthopanax was shown to be correlated with the content of EN-SP. These results demonstrated that competitive ELISA was a convenient, fast, reproducible, and accurate method for the determination of EN-SP as an immunologically active standard substance in extract of A. senticosus.

• Journal of Microbiology and Biotechnology
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• v.31 no.9
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• pp.1241-1255
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• 2021

This study was carried out to explore a non-chemical strategy for enhancing productivity by employing some antagonistic rhizobacteria. One hundred eighteen bacterial isolates were obtained from the rhizospheric zone of various crop fields of Gangwon-do, Korea, and screened for antifungal activity against Fusarium wilt (Fusarium oxysporum f. sp. lactucae) in lettuce crop under in vitro and in vivo conditions. In broth-based dual culture assay, fourteen bacterial isolates showed significant inhibition of mycelial growth of F. oxysporium f. sp. lactucae. All of the antagonistic isolates were further characterized for the antagonistic traits under in vitro conditions. The isolates were identified on the basis of biochemical characteristics and confirmed at their species level by 16S rRNA gene sequencing analysis. Arthrobacter sulfonivorans, Bacillus siamensis, Bacillus amyloliquefaciens, Pseudomonas proteolytica, four Paenibacillus peoriae strains, and Bacillus subtilis were identified from the biochemical characterization and 16S rRNA gene sequencing analysis. The isolates EN21 and EN23 showed significant decrease in disease severity on lettuce compared to infected control and other bacterial treatments under greenhouse conditions. Two bacterial isolates, EN4 and EN21, were evaluated to assess their disease reduction and growth promotion in lettuce in field conditions. The consortium of EN4 and EN21 showed significant enhancement of growth on lettuce by suppressing disease caused by F. oxysporum f. sp. lactucae respectively. This study clearly indicates that the promising isolates, EN4 (P. proteolytica) and EN21 (Bacillus siamensis), can be commercialized and used as biofertilizer and/or biopesticide for sustainable crop production.

• Archives of Pharmacal Research
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• v.27 no.2
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• pp.217-224
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• 2004

Previously, we reported that water-extracted Acanthopanax senticasus exhibited anti-meta-static activity by stimulating the immune system. In this study, we fractionated glycoproteins (EN-SP) from the soluble protein layer (GF-AS) of A. senticasus and determined their basic chemical properties. We also investigated the anti-tumor and immunostimulating activities of the fractionated glycoprotein, EN-SP. We found that intravenous (i.v.) administration of GF-AS dramatically inhibited metastasis of colon26-M3.1 carcinoma cells to the lung in a dose-dependent manner. In vitro analysis showed GF-AS to enhance the proliferation of splenocytes. GF-AS also stimulated peritoneal macrophage, which was followed by the production of various cytokines such as IL-1$\beta$, TNF-$\alpha$, IL-12 and IFN-${\gamma}$. Furthermore, the production of these cytokines was partially blocked when peritoneal macrophage was cultured with the polyclonal antibodies against GF-AS. The depletion of NK cells by rabbit anti-asialo GM1 serum partly abolished the inhibitory effect of GF-AS on lung metastasis of colon26-M3.1 cells. Using gel filtration, EN-SP, an active glycoprotein fraction, is isolated from GF-AS. While both GF-AS and EN-SP stimulated the proliferatation of splenocytes of normal mice, EN-SP showed higher anti-metastatic activity and more potently stimulated the proliferation of splenocytes compared to GF-AS. These results suggest the use of EN-SP, the fractionated glycoprotein from A. senticasus, can be used as a therapeutical reagent to prevent or inhibit tumor metastasis.

• The Korean Journal of Mycology
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• v.25 no.1 s.80
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• pp.10-19
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• 1997

Fusarium wilt of radish (Raphanus sativus L.) is caused by the Fusarium oxysporum f. sp. raphani (FOR) which mainly attacks Raphanus spp. The pathogen is a soil-borne and forms chlamydospores in infected plant residues in soil. Infected pathogen colonizes the vascular tissue, leading to necrosis of the vascular tissue. Growth promoting beneficial organisms such as Pseudomonas fluorescens WCS374 (strain WCS374), P. putida RE10 (strain RE10) and Pseudomonas sp. EN415 (strain EN415) were used for microorganisms-mediated induction of systemic resistance in radish against Fusarium wilt. In this bioassy, the pathogens and bacteria were treated into soil separately or concurrently, and mixed the bacteria with the different level of combination. Significant suppression of the disease by bacterial treatments was generally observed in pot bioassy. The disease incidence of the control recorded 46.5% in the internal observation and 21.1% in the external observation, respectively. The disease incidence of P. putida RE10 recorded 12.2% in the internal observation and 7.8% in the external observation, respectively. However, the disease incidence of P. fluorescens WCS374 which was proved to be highly suppressive to Fusarium wilt indicated 45.6% in the internal observation and 27.8% in the external observation, respectively. The disease incidence of P. putida RE10 mixed with P. fluorescens WCS374 or Pseudomonas sp. EN415 was in the range of 10.0-22.1%. On the other hand, the disease incidence of P. putida RE10 mixed with Pseudomonas sp. EN415 was in the range of 7.8-20.2%. The colonization by FOR was observed in the range of $2.4-5.1{\times}10^3/g$ on the root surface and $0.7-1.3{\times}10^3/g$ in the soil, but the numbers were not statistically different. As compared with $3.8{\times}10^3/g$ root of the control, the colonization of infested ROR indicated $2.9{\times}10^3/g$ root in separate treatments of P. putida RE10, and less than $3.8{\times}10^3/g$ root of the control. Also, the colonization of FOR recorded $5.1{\times}10^3/g$ root in mixed treatments of 3 bacterial strains such as P. putida RE10, P. fluorescens WCS374 and Pseudomonas sp. EN415. The colonization of FOR in soil was less than that of FOR in root part. Based on soil or root part, the colonization of ROR didn't indicate a significant difference. The colonization of introduced 3 fluorescent pseudomonads was observed in the range of $2.3-4.0{\times}10^7/g$ in the root surface and $0.9-1.8{\times}10^7/g$ in soil, but the bacterial densities were significantly different. When growth promoting organisms were introduced into the soil, the population of Pseudomonas sp. in the root part treated with P. putida RE10 was similar in number to the control and recorded the low numerical value as compared with any other treatments. The population density of Pseudomonas sp. in the treatment of P. putida RE10 indicated significant differences in the root part, but didn't show significant differences in soil. The population densities of infested FOR and introduced bacteria on the root were high in contrast to those of soil. P. putida RE10 and Pseudomonas sp. EN415 used in this experiment appeared to induce the resistance of the host against Fusarium wilt.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.12
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• pp.2655-2663
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• 2011

Several algorithms have been developed to detect AF which rely either on the form of P waves or the based on the time frequency domain analysis of RR variability. However, locating the P wave fiducial point is very difficult because of the low amplitude of the P wave and the corruption by noise. Also, the time frequency domain analysis of RR variability has disadvantage to get the details of irregular RR interval rhythm. In this study, we describe an atrial fibrillation detection algorithm through non-linear analysis of irregular RR interval rhythm based on the variability, randomness and complexity. We employ a new statistical techniques root mean squares of successive differences(RMSSD), turning points ratio(TPR) and sample entropy(SpEn). The detection algorithm was tested using the optimal threshold on two databases, namely the MIT-BIH Atrial Fibrillation Database and the Arrhythmia Database. We have achieved a high sensitivity(Se:94.5%), specificity(Sp:96.2%) and Se(89.8%), Sp(89.62%) respectively.

• Environmental Analysis Health and Toxicology
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• v.24 no.4
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• pp.311-320
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• 2009

The short term (24-hr) and long term (21 days) effects of copper, cadmium, fenbendazole and sulfathiazole on the survival of the Korean fairy shrimp Branchinella kugenumaensis were evaluated. The 24-hr median lethal concentrations ($LC_{50}$) of copper, cadmium, fenbendazole, and sulfathiazole were 39, 512, 182, and 31,818 ${\mu}g/L$, respectively. The toxicity of copper is highest among 4 chemicals used in this study, while sulfathazole the lowest. After the long term (21 days) exposure experiment, the $LC_{50}$ copper, cadmium, fenbendazole, and sulfathiazole were 1.12, 2.1, 0.1, 6.6 ${\mu}g/L$, respectively. The long term effects of antibiotics were highly enhanced while the short-term effects were not strong. The sensitivities of B. kugenumaensis to copper and cadmium were higher than or comparable to those of other freshwater branchiopods (Streptocephalus spp., Thamnocephalus sp.), and far higher than the marine species (Artemia sp.). There were significant effects on the survival of B. kugenumaensis after long term exposure to relatively lower concentrations of copper, cadmium, fenbendazole and sulfathiazole. Therefore, B. kugenumaensis seems quite a good candidate species for the ecotoxicological assessments of freshwater environments.

• Analytical Science and Technology
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• v.22 no.5
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• pp.376-385
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• 2009

In our study, the accuracy for measurement of seventeen 2,3,7,8-substituted PCDDs/PCDFs in certified reference material (CRM) which is the sample of homogeneous sediment matrix taken from an area known to have significant chemical contamination, particularly PCBs (polychlorinated biphenyls), was evaluated. Though the methodology in this study followed the official method of unintentionally produced persistent organic pollutants (UPOPs) announced by the Ministry of Environment of the Republic of Korea in 2007, there were slight changes using additional purification step by activated carbon column because the interferences of sample were not sufficiently removed when only multi-silica column and alumina column have been used for purification. The |En| number proposed by the Korea Research Institute of Standards and Science was used for a valuation basis of the accuracy. The |En| numbers of seventeen 2,3,7,8-substituted PCDDs/PCDFs have been indicated as 1 and below, they were decided "Pass" in this test, when DB-5MS column and SP-2331 column were used together. Because 1,2,3,7,8-PeCDD and #169-HxCB were not separated on DB-5MS column, the ions of 1,2,3,7,8-PeCDD were selected at M/M+2 instead of M+2/M+4 suggested by EPA 1613. It is possible to distinguish them in HRGC/HRMS analysis.

• Journal of the Korean Chemical Society
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• v.35 no.6
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• pp.607-611
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• 1991

The stereochemical ratio cis and trans isomer of the hydration reaction of trans-$[Co(en)(tmd)Cl_2]^+$ complex ion were studied with varing temperature by the spectrophotometric method. It was observed that the ratio of cis-isomer was about 30%, and the intermediate was rearranged. And in order to investigate this mechanism more clearly, stability energy profile, interaction diagram and orbital correlation diagram were calculated by the EHT method. By the calculation, the mechanism of cis-isomer was in good agreement with the experimental results, and it was estimated that the hydration reaction was carried through some distorted square pyramid (sp).

• Korean Journal of Agricultural Science
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• v.21 no.1
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• pp.60-66
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• 1994

Among the various bacterial isolates from municipal sewages which utilized linear alkylbenzene sulfonate (LAS) as a sole source of carbon. 3 potent strains - KL-3, SH-2 and EN-1 - were selected. The strains were classified: KL-3 as a strain belong to the genus Klebsiella; SH-2 Shigella; and EN-1 Enterobacter, respectively. They were grown in a broth containing 200 ppm of LAS, using a laboratory scale fermentor: the bacterial growth reached stationary phase after 2 days with a maximum viability of $10^8cfu/mL$ of the culture; initial rates of LAS degradation were high during the first 24 hours of cultivation (KL-3 and SH-2, approx. 50%; EN-1, 20%); after 1 day a lag period of about 24 hours was observed for all the strains, and thereafter break-down proceeded rapidly; final rates after 7 days were approximately 85% by KL-3, 82% by SH-2 and 75% by EN-1. Adsorption of LAS by the bacterial cell mass was high for the strain SH-2, as Freundlich equation: Y= 0.030X + 0.95 was calculated.