• Molecules and Cells
• /
• v.37 no.2
• /
• pp.109-117
• /
• 2014

Microbiota in the niches of the rhizosphere zones can affect plant growth and responses to environmental stress conditions via mutualistic interactions with host plants. Specifically, some beneficial bacteria, collectively referred to as Plant Growth Promoting Rhizobacteria (PGPRs), increase plant biomass and innate immunity potential. Here, we report that Enterobacter sp. EJ01, a bacterium isolated from sea china pink (Dianthus japonicus thunb) in reclaimed land of Gyehwa-do in Korea, improved the vegetative growth and alleviated salt stress in tomato and Arabidopsis. EJ01 was capable of producing 1-aminocy-clopropane-1-carboxylate (ACC) deaminase and also exhibited indole-3-acetic acid (IAA) production. The isolate EJ01 conferred increases in fresh weight, dry weight, and plant height of tomato and Arabidopsis under both normal and high salinity conditions. At the molecular level, short-term treatment with EJ01 increased the expression of salt stress responsive genes such as DREB2b, RD29A, RD29B, and RAB18 in Arabidopsis. The expression of proline biosynthetic genes (i.e. P5CS1 and P5CS2) and of genes related to priming processes (i.e. MPK3 and MPK6) were also up-regulated. In addition, reactive oxygen species scavenging activities were enhanced in tomatoes treated with EJ01 in stressed conditions. GFP-tagged EJ01 displayed colonization in the rhizosphere and endosphere in the roots of Arabidopsis. In conclusion, the newly isolated Enterobacter sp. EJ01 is a likely PGPR and alleviates salt stress in host plants through multiple mechanisms, including the rapid up-regulation of conserved plant salt stress responsive signaling pathways.

• Journal of Microbiology and Biotechnology
• /
• v.25 no.1
• /
• pp.109-118
• /
• 2015

Open raceway ponds are cost-efficient for mass cultivation of microalgae compared with photobioreactors. Although low-cost options like wastewater as nutrient source is studied to overcome the commercialization threshold for biodiesel production from microalgae, a cost analysis on the use of wastewater and other incremental increases in productivity has not been elucidated. We determined the effect of using wastewater and wavelength filters on microalgal productivity. Experimental results were then fitted into a model, and cost analysis was performed in comparison with control raceways. Three different microalgal strains, Chlorella vulgaris AG10032, Chlorella sp. JK2, and Scenedesmus sp. JK10, were tested for nutrient removal under different light wavelengths (blue, green, red, and white) using filters in batch cultivation. Blue wavelength showed an average of 27% higher nutrient removal and at least 42% higher chemical oxygen demand removal compared with white light. Naturally, the specific growth rate of microalgae cultivated under blue wavelength was on average 10.8% higher than white wavelength. Similarly, lipid productivity was highest in blue wavelength, at least 46.8% higher than white wavelength, whereas FAME composition revealed a mild increase in oleic and palmitic acid levels. Cost analysis reveals that raceways treating wastewater and using monochromatic wavelength would decrease costs from 2.71 to 0.73 $/kg biomass. We prove that increasing both biomass and lipid productivity is possible through cost-effective approaches, thereby accelerating the commercialization of low-value products from microalgae, like biodiesel.

• Journal of Soil and Groundwater Environment
• /
• v.20 no.3
• /
• pp.25-33
• /
• 2015

In this study, Fe₃O₄-ACCS-Ag nanoparticles (NPs) were successfully synthesized using silica extracted from corn cob ash. The synthesized Fe₃O₄-ACCS-Ag NPs were characterized using X-ray diffraction (XRD), scanning electron microscopyenergy dispersive X-ray spectroscopy (SEM-EDX), transmission electron microscopy (TEM) and fourier transform infrared spectroscopy (FTIR). In addition, the potential application of Fe₃O₄-ACCS-Ag NPs as an antibacterial material in water disinfection was investigated using Escherichia coli ATCC 8739 as model bacteria. The antibacterial activity of synthesized composite material showed 99.9% antibacterial effect within 20 min for the tested bacteria. From this experiment, the synthesized Fe₃O₄-ACCS-Ag nanocomposites also hold magnetic properties and could be easily recovered from the water solution for its reuse. The reused nanocomposites presented the decreasing antibacterial efficiencies with the reuse cycle but the composite used three times still killed 90% of bacteria in 20 min.

• Archives of Pharmacal Research
• /
• v.28 no.10
• /
• pp.1170-1176
• /
• 2005

2-Methyl-2-(2-methylpropenyl)-2,3-dihydronaphthoquinone[2,3-b]furan-4,9-dione (N FD-37) is a synthetic furonaphthoquinone compound. In this study, we determined that NFD-37 could inhibit the lipopolysaccharide (LPS)-induced production of inflammatory mediators in macrophages RAW 264.7. This compound inhibited LPS-induced nitric oxide (NO) or prostaglandin (PG) $E_{2}$ production in dose-dependent manners, with $IC_{50}$ values of 7.2 ${\mu}M$ and 5.3 ${\mu}m$, respectively. As the positive controls, pyrrolidine dithiocarbamate (30 ${\mu}M$) exhibited a $57{\%}$ inhibition of NO production, and NS-398 ($1{\mu}M$) manifested a $48{\%}$ inhibition of $PGE_2$ production. The inhibitory effects of NFD-37 on NO and $PGE_2$ production were determined to occur in conjunction with the suppression of inducible NO synthase or cyclooxygenase-2 expression. NFD-37 also inhibited the production of LPS-inducible tumor necrosis factor-${\alpha}$, interleukin (IL)-$1{\beta}$ and IL-6, at $IC_{50}$ values of 4.8-8.9 ${\mu}M$. We also determined the anti-inflammatory efficacy of NFD-37 using carrageenin-induced paw edema in experimental mice.

• Proceedings of the Membrane Society of Korea Conference
• /
• 2004.05a
• /
• pp.82-85
• /
• 2004

Microinterface of W/Omicroemulsion prepared by phosphatidylcholine was used as reaction media of hydrolysis of phosphatidylcholine by phospholipaseA$_2$. Phosphatidylcholine was used as an amphiphile and was acted as a substrate. Organic phase of W/Omicroemulsion in this study was prepared by mixed organic solvents i.e. 2,2,4-trimethylpentane (isooctane) as a main solvent and 1-butanol as a co-solvent. The effect of added 1-butanol was remarkable not only on reaction beginning but also on high reaction rate. The hydrolysis reaction was dramatically initiated when 1-butanol was injected into the running isooctane/PC system. The enhancement by 1-butanol addition into single organic solvent was our original finding compare with previous conventional organic solvent. The reaction rate was elevated by the added amount of 1-butanol. The enhanced reaction rate was about 150-folds. This enhancement was speculated as 1-butanol adsorption on the microinterface. The adsorbed 1-butanol improved the properties of microinterface, especially its mobility was increased by difference of the chain length between phosphatidylcholine and 1-butanol. PhospholipaseA$_2$ molecules were located on the microinterface due to modified mobility of microinterface. Located phospholipaseA$_2$ on the microinterface reacted easily with phosphatidylcholine molecule. As a result high reaction rate was obtained. Microinterfacial properties were successfully improved by adsorbed 1-butanol molecule, and were favorable to appear higher reactivity of phospholipaseA$_2$.

• Korean Journal of Pharmacognosy
• /
• v.34 no.3 s.134
• /
• pp.242-245
• /
• 2003

The effects of chelidonine, a benzophenanthridine isoquinoline alkaloid, on L-DOPA-induced cytotoxicity in PC12 cells were investigated. The treatment of PC12 cells with chelidonine $(1-4\;{\mu}M)$ decreased dopamine content in a dose-dependent manner (30.2% inhibition at $4\;{\mu}M)$. Chelidonine was not cytotoxic up to $4\;{\mu}M)$. However, chelidonine at concentrations higher than $5\;{\mu}M$ caused a cytotoxicity in PC12 cells. L-DOPA at concentrations higher than $50\;{\mu}M$ led to cell damage by oxidative stress in PC12 cells. Chelidonine at non-cytotoxic concentration ranges of $1-4{\mu}M$ aggravated L- DOPA $(20-50\;{\mu}M)$-induced cytotoxicity in PC12 cells. The L-DOPA-induced cytotocxicity was synergistically stimulated by chelidonine at concentrations grader than $5\;{\mu}M$. These data demonstrate that chelidonine exacerbates L-DOPA-induced cytotoxicity. Therefore, it is proposed that the long-term L-DOPA therapeutic patients with chelidonine may need to be checked for the adverse symptoms.

• Mycobiology
• /
• v.47 no.2
• /
• pp.256-260
• /
• 2019

Neuraminidase (NA) cleaves the glycosidic bond linkages of sialic acids to release the mature virions from infected cells and has been an attractive therapeutic target for anti-influenza agents. In our ongoing investigation of NA inhibitors in mushroom extracts, we found that the extract the fruiting body of Glaziella splendens potently inhibited neuraminidase. The fruiting bodies of G. splendens were extracted and partitioned successively with hexane, ethyl acetate, and butanol. The ethyl acetate soluble-layer was subjected to silica gel and Sephadex LH-20 column chromatographies, and MPLC to obtain five compounds (1-5). Their structures were determined by spectroscopic methods. NA inhibitory activity of these compounds was evaluated using NAs from recombinant rvH1N1, H3N2, and H5N1 influenza A viruses. One compound (1) was elucidated as a new azaphilone derivative, and four compounds (2-5) were identified as entonaemin A, comazaphilone D, rubiginosin A, and entonaemin B, respectively. Compounds 3 and 4 showed considerable inhibitory activity against three types of neuraminidases with the $IC_{50}$ values of 30.9, 41.8, and $35.7{\mu}M$ for 3 and 46.5, 50.4, and $29.9{\mu}M$ for 4, respectively. This study reveals that the fruiting bodies of G. splendens possess azaphilone derivatives with the NA inhibitory activity. This is the first report on the isolation of neuraminidase inhibitors from the fruiting bodies of G. splendens.

• Asian-Australasian Journal of Animal Sciences
• /
• v.32 no.6
• /
• pp.842-848
• /
• 2019

Objective: Heat stress poses an increasing threat for poultry production. Some amino acids have been found to play critical roles in affording thermotolerance. Recently, it was found that in ovo administration of L-leucine (L-Leu) altered amino acid metabolism and afforded thermotolerance in heat-exposed broiler chicks. Methods: In this study, two doses (35 and $70{\mu}mol/egg$) of L-Leu were administered in ovo on embryonic day 7 to determine their effect on rectal temperature (RT), body weight (BW) and thyroid hormones at hatching. Changes in RT, BW, and thermotolerance in post-hatched chicks were also analyzed. Results: It was found that in ovo administration of L-Leu dose-dependently reduced RT and plasma thyroxine ($T_4$) level just after hatching. In post-hatched neonatal broiler chicks, however, the higher dose of L-Leu administered in ovo significantly increased RT without affecting BW gain. In chicks that had been exposed to heat stress, the RT was significantly lowered by in ovo administration of L-Leu (high dose) in comparison with the control chicks under the same high ambient temperature (HT: $35^{\circ}C{\pm}1^{\circ}C$, 120 min). Conclusion: In ovo administration of L-Leu in a high dose contributed to an increased daily body temperature and afforded thermotolerance under HT in neonatal broiler chicks.

• Proceedings of the Plant Resources Society of Korea Conference
• /
• 2019.10a
• /
• pp.105-105
• /
• 2019

Much of bacteria inhabit intestine and affect health. To elucidate the composition of intestinal bacteria and biological activities of plant materials on the bacteria, bacterial strains are need to be isolated and identified. In previous study, we isolated 41 fecal bacteria of BALB/c mice and the strains were identified as 11 species including Lactobacillus murinus and not classified bacterium. To expand the bacterial resources, we tried to isolate more bacteria from C57BL/6 mice. Fresh feces was suspended and serially diluted in distilled water. The aliquots were inoculated on GAM agar plate and incubated anaerobically at $37^{\circ}C$ for 48 h. Each of colony formed was picked up and incubated again on GAM agar plate for stock and sampling. The bacteria gained were analyzed and identified by 16S rRNA gene. The bacterial strain were listed up. Major strain was Lactobacillus murinus which was observed as an abundant strain of BALB/c mice. The resources could be used for experiments of biological activities of plant materials and microbial composition of intestinal contents of experimental animals.

• Mycobiology
• /
• v.49 no.6
• /
• pp.604-606
• /
• 2021

In our ongoing search for new secondary metabolites from fungal strains, one novel compound (1) and nine known compounds (2-10) were isolated from the EtOAc-soluble layer of the culture broth of Panus rudis. The culture broth of P. rudis was extracted in acetone and fractionated by solvent partition; column chromatography using silica gel, Sephadex LH-20, and Sephadex G-10; MPLC; and HPLC. The structures of isolated compounds were elucidated by one- and two-dimensional NMR and LC-ESI-mass measurements. One new compound, panepoxydiol (1), and nine known compounds, (E)-3-(3-hydroxy-3-methylbut-1-en-1-yl)-7-oxabicyclo[4.1.0]hept-3-ene-2,5-diol (2), isopanepoxydone (3), neopanepoxydone (4), panepoxydone (5), panepophenanthrin (6), 4-hydroxy-2,2-dimethyl-6-methoxychromane (7), 6-hydroxy-2,2-dimethyl-3-chromen (8), 2,2-dimethyl-6-methoxychroman-4-one (9), 3,4-dihydroxy-2,2-dimethyl-6-methoxychromane (10), were isolated from the culture broth of P. rudis. This is the first report of isolation of a new compound panepoxydiol (1) and nine other chemical constituents (2-5, 7-10) from the culture broth of P. rudis.