• Fisheries and Aquatic Sciences
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• v.14 no.3
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• pp.179-185
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• 2011

The antioxidant activities of a methanolic extract of Eisenia bicyclis and its organic solvent fractions, including dichloromethane ($CH_2Cl_2$), ethyl acetate (EtOAc), n-butanol (n-BuOH), and water ($H_2O$) fractions, were investigated. Scavenging activities against DPPH, hydroxyl, superoxide anion, and peroxynitrite radicals were evaluated using electron spin resonance spectrometry; intracellular reactive oxygen species (ROS) were evaluated by a 2',7'-dichlorofluorescein diacetate assay using RAW264.7 mouse macrophages. The antioxidant activities of the individual fractions were: EtOAc>n-BuOH>$CH_2Cl_2$ >$H_2O$. The EtOAc fraction exhibited strong radical scavenging activity and a significantly reduced ROS level in RAW264.7 cells. Moreover, the phenolic contents of the extract and fractions followed the same order as their radical scavenging activities. Our results indicate that E. bicyclis is a valuable natural source of antioxidants that may be applicable to the functional food industry.

• Microbiology and Biotechnology Letters
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• v.34 no.4
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• pp.289-298
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• 2006

3',5'-cyclic adenosine monophosphate (cAMP) is an important molecule, which mediates diverse cellular processes. For example, it is involved in regulation of sugar uptake/catabolism, DNA replication, cell division, and motility in various acterial species. In addition, cAMP is one of the critical regulators for syntheses of virulence factors in many pathogenic bacteria. It is believed that cAMP acts as a signal for environmental changes as well as a regulatory factor for gene expressions. Therefore, intracellular concentration of cAMP is finely modulated by according to its rates of synthesis (by adenylate cyclase), excretion, and degradation (by cAMP phosphodiesterase). In the present review, we discuss the bacterial physiological characteristics governed by CAMP and the molecular mechanisms for gene regulation by cAMP. Furthermore, the effect of cAMP on phosphotransferase system is addressed.

• Korean Journal of Microbiology
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• v.23 no.1
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• pp.13-19
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• 1985

Acc I endonuclease has been isolated from 300g (wet weight) cells of Acinetobacter calcoaceticus. The cells were broken by using French press at 20, 000p.s.i. After ammonium sulfate fractionation, the enzyme was further purified by heparin agarose, DEAE-sephades, Affi.-gel Blue, phosphocellulose, and hydroxylapatite column chromatography. The purified Acc I endonudlease has a single polypeptide species and its subunit molecular weight was 45,000 ${\pm}$ 1,000 daltons as judged by 10% SDS-polyacrylamide gel electrophoresis. The isolated enzyme was essentially free of contaminating nucleases as judged by homochromatography by using a $^{32}P-labeled$ oligonucleotide. The enzyme showed maximum activity at pH values between 8.0 and 11.0 and in the presence of $MgCl_2$. Acc I endonuclease was maximally active in the absence of NaCl and was completely inhibited at 200 mM NaCl.

• Journal of Microbiology
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• v.35 no.2
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• pp.117-122
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• 1997

Several dominant 4-CPA-degrading bacteria were isoalted from agricultural soils. Most of the isolates were identified as Burkholderia species by fatty acid methyl ester (FAME) analysis, but they were idstinct in chromosomal patterns obtained by PCR amplification of repetitive extragenic palindromic (REP) sequences. These strains were generally restricted in their substrate utilization capabilities. The 4-CPA degradative enzymes were idnducible by 4-CPA and some isolates appeared to mineralize 4-CPA via formation of 4-chlorophenol and 4-chlorocatechol as intermediates during its biodegradation pathway. Plasmid DNAs were not detected from most of the isoaltes and their 4-CPA genes wer on the chromosomal DAN. The 4-CPA degradation patterns in axenic cultures and natural soils varied depending on the strains and soils. The inoculation of 4-CPA degraders much improved the removal of 4-CPA from the 4-CPA treated soils.

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.335-339
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• 2005

Enterobacteria, named ${\lambda}-bacteria$ isolated from fusiform fish bearing higher antioxidative capacity with ORP values, ${\lambda}-28$ strain bore higher anti-angiogenesis effect than other ${\lambda}-species$. Optimum growth condition of ${\lambda}-28$ bacterium was $25^{\circ}C$, neutral pH, Glc as a C-source, ammonium chloride as a N-source, and not effected with organic N-source.

• BMB Reports
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• v.45 no.10
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• pp.589-594
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• 2012

Paclitaxel is produced by various species of yew trees and has been extensively used to treat tumors. In our research, a taxadiene synthase (TS) gene from Taxus brevifolia was used to transform the roots of cultured ginseng (Panax ginseng C.A. Meyer) to produce taxadiene, the unique skeletal precursor to taxol. The TS gene was successfully introduced into the ginseng genome, and the de novo formation of taxadiene was identified by mass spectroscopy profiling. Without any change in phenotypes or growth difference in a TS-transgenic ginseng line, the transgenic TSS3-2 line accumulated $9.1{\mu}g$ taxadiene per gram of dry weight. In response to the treatment of methyl jasmonate for 3 or 6 days, the accumulation was 14.6 and $15.9{\mu}g$ per g of dry weight, respectively. This is the first report of the production of taxadiene by engineering ginseng roots with a taxadiene synthase gene.

• The Plant Pathology Journal
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• v.24 no.1
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• pp.58-62
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• 2008

Utilization of carbon sources by Bacillus cereus D324, a biological control agent, and Pythium species, which causes rice seedling disease, was studied with the objective of increasing the efficacy of biological control by providing the biological control agent with specific beneficial carbon sources. D-galactose, D-sorbitol, and D-mannitol were poor carbon sources for Pythium spp. growth but were good for B. cereus D324 growth. Growth in a growth chamber of rice seeds coated with B. cereus D324 amended with specific carbon sources, such as D-galactose and D-sorbitol, showed significantly enhanced seedling emergence compared to seeds coated only with B. cereus D324. Field trials showed that both seedling emergence and yield increased, when the above specific carbon sources were added to B. cereus D324 in seed coating formulations. This result indicated that amending seed coating formulations with specific carbon sources could significantly increase seedling emergence and yield in the field.

• Korean Journal Plant Pathology
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• v.3 no.2
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• pp.85-92
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• 1987

The present researches were carried out to differentiate the species of Colletotrichum by elecrophoretic method. C. gloeosporioides, C. dematium and Gloeosporium fructigenum could be differentiated by the isozyme patterns of esterase, leucine aminopeptidase, acid phosphatase and glutamic oxaloacetic transaminase. Especially. G-strain and R-strain of C. gloeosporioides were differentiated by the enzyme patterns. The G­strain damaged all stage fruits (green and red fruits) of Capsicum annum. The R-strain could not infect the unripe (green) fruits, but it could damage only ripe (red) fruit of Capsicum annum.

• Parasites, Hosts and Diseases
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• v.48 no.4
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• pp.297-301
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• 2010

Recently, emerging waterbome protozoa, such as microsporidia, Cyclospora, and Cryptosporidium, have become a challenge to human health worldwide. Rapid, simple, and economical detection methods for these major waterborne protozoa in environmental and clinical samples are necessary to control infection and improve public health. In the present study, we developed a multiplex PCR test that is able to detect all these 3 major waterborne protozoa at the same time. Detection limits of the multiplex PCR method ranged from $10^1$ to $10^2$ oocysts or spores. The primers for microsporidia or Cryptosporidium used in this study can detect both Enterocytozoon bieneusi and Encephalitozoon intestinalis, or both Cryptosporidium hominis and Cryptosporidium paNum, respectively. Restriction enzyme digestion of PCR products with BsaBI or BsiEI makes it possible to distinguish the 2 species of microsporidia or Cryptosporidium, respectively. This simple, rapid, and cost-effective multiplex PCR method will be useful for detecting outbreaks or sporadic cases of waterborne protozoa infections.

• Parasites, Hosts and Diseases
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• v.53 no.1
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• pp.101-104
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• 2015

A nematode species belonging to the genus Cosmocephalus was collected from the stomach of 2 common gulls, Larus canus. The common gulls were found dead on the seaside of Gangneung City, the Republic of Korea. The worms were identified and classified by light (LM) and scanning electron microscopy (SEM) on the basis of important taxonomic characters. The nematodes were characterized by a body length 9.1-9.3 mm (males) and 15.5-15.9 mm (females) and cordons recurrent in anterior direction and anastomosing laterally at about the level of anterior quarter of the buccal cavity. The salient bicuspid deirids were located on the posterior to the cordons. Lateral alae were well-developed, extending from the level just posterior of deirids to the level about middle of the body. LM and SEM observations identified the worms as C. obvelatus. This is the first reported case of C. obvelatus infection in common gulls in Korea.