• Journal of Life Science
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• v.28 no.12
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• pp.1424-1431
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• 2018

We prepared flocculated detritus-like organic marine snow originating from various organisms by fermentation using microorganisms; this fermented organic material was fed to the leptocephali of the eel (Anguilla japonica) to investigate whether or not such organic matter was an appropriate food source for the larvae. A strain was isolated from a biofloc technology system used to culture fish, and seven types of organic material from hen's egg, eel muscle, tuna muscle, lugworm, shrimp, manila clam, mussel, and sea squirt were fermented using isolated bacteria (Bacillus sp.). The fermented matter did not show any specific form and was larger than $10-20{\mu}m$ but no more than $100{\mu}m$ in size. Four diets (A-D) were prepared using the various fermented products, and the larvae were fed the prepared food from 20 days after hatching. The leptocephali fed the A, B, and C diets survived until 37, 39, and 37 days after hatching, respectively. However, the leptocephali fed the D diet survived for 60 days after hatching. The protein content of each diet was very similar, but the n-3 HUFA concentration in the D diet was approximately twice as high as that of the others.

• Korean Chemical Engineering Research
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• v.57 no.5
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• pp.611-619
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• 2019

This study was carried out to investigate fuel decomposition characteristics and coke formation according to types of endothermic fuels and methods of catalyst molding. Methylcyclohexane (MCH), n-dodecane, and exo-tetrahydrodipentadiene (exo-THDCP) were used as the endothermic fuels. As a catalyst, USY720 supported with platinum was used. It was manufactured by only using pressure to disk-type, or pelletized with a binder and a silica solution. The characteristics of the catalysts according to the molding method were analyzed by X-ray diffraction analysis, scanning electron microscopy, nitrogen adsorption-desorption isotherm, and ammonia temperature programmed desorption analysis. The reaction was carried out under conditions of high temperature and high pressure ($500^{\circ}C$, 50 bar) in which the fuel could exist in a supercritical state. The product was analyzed by gas chromatograph/mass spectrometer and the coke produced by the catalyst was analyzed by thermogravimetric analyzer. After the reaction, the composition of the products varied greatly depending on the structure of the fuel. In addition, the crystallinity and surface properties of the catalysts were not changed by the method of catalyst molding, but the changes of the acid sites and the pore characteristics were observed, which resulted in changes in the amount and composition of products and coke.

• 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.

• Korean Journal of Poultry Science
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• v.35 no.4
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• pp.361-366
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• 2009

The purpose of this study was to assess the genetic variation and establish the relationship amongst breeds and strains using 7 chicken specific microsatellite markers. A total of 317 DNA samples from four Korean native chicken (KNC) strains (KR: Korean Native Red chicken strain, KY: Korean Native Yellow chicken strain, KL: Korean Native Black chicken strain, KO: Ogol chicken strain) and three introduced endemic chicken breeds (LE: Leghorn chicken breed, RI: Rhode Island Red chicken breed, CO: Cornish chicken breed). The size of microsatellite markers was decided using GeneMapper Software (v.4.0) after being analyzed using an ABI 3130 Genetic Analyzer. Frequencies of microsatellites markers were used to estimate heterozygosities and genetic distances. The lowest distance (0.074) was observed between the KY and KL breeds and the highest distance (0.779) between the KL and LE breeds. The KNC strains (KR, KY, KL) have comparatively near genetic distance each other. On the other side, each individual was not ramified to different groups and were spread evenly in phylogenetic dendrogram about all the KNC of each strain populations. But the endemic breed populations (LE, RI, CO) were ramified to different groups. The microsatellite polymorphism data were shown to be useful for assessing the genetic relationship between Korean native strains and other foreign breeds.

• Analytical Science and Technology
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• v.27 no.2
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• pp.92-99
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• 2014

Interferences were removed using anion exchange solid phase extraction (AE SPE) in quantification of selenoproteins in Korean human blood serum with affinity high performance liquid chromatography (AF HPLC)-inductively coupled plasma/mass spectrometry (ICP/MS). The average selenium level obtained for healthy Koreans was $94.3{\pm}2.3ngg^{-1}$ using isotope dilution method. AE SPE was coupled to AF column to separate 3 selenoproteins, glutathione peroxidase GPx, selenoprotein SelP, and selenoalbumin SeAlb. Post column isotope dilution was employed to quantify the proteins. The certified reference material of human blood serum BCR-637 was analyzed to give total selenoprotein concentration of $85.4{\pm}3.4ngg^{-1}$, which agreed well with the reference value of $81{\pm}7ngg^{-1}$. The pooled concentration of GPx, SelP, and SeAlb from healthy Koreans (n=20) was $12.1{\pm}1.4ngg^{-1}$, $57.2{\pm}2.0ngg^{-1}$, and $20.0{\pm}1.9ngg^{-1}$, respectively. The sum of selenoproteins is $89.3ngg^{-1}$, which is about the same as the total selenium concentration of $94.3ngg^{-1}$. The fact suggests that selenium in blood serum is mostly consisted of selenoproteins. After the removal of interference, GPx showed a significant decrease (more than 50%) from $25.0ngg^{-1}$ to $12.1ngg^{-1}$. It was identified that the interference in blood serum was mostly from GPx and the use of AE SPE was proven to be efficient in eliminating Cl and Br that cause interference to GPx.

• Korean Journal of Food Science and Technology
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• v.50 no.2
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• pp.152-164
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• 2018

Fermented seasoning pastes were prepared by Aspergillus oryzae and Bacillus subtilis using three edible insects, Tenebrio molitor larvae (TMP), Gryllus bimaculatus (GBP), and Bombyx mori pupa (SPP), with soybean (SBP) as a negative control. Volatile compounds were extracted by the headspace solid-phase microextraction (HS-SPME) method and confirmed by gas chromatograph-mass spectrometry (GC-MS). In total, 121 volatiles from four samples were identified and sub-grouped as 11 esters, 18 alcohols, 23 aldehydes, 5 acids, 10 pyrazines, 2 pyridines, 7 aromatic hydrocarbons, 10 ketones, 19 alkanes, 9 amides, 4 furans and 3 miscellaneous. TMP, GBP, SPP and SBP had 48, 54, 36, and 55 volatile compounds, respectively. Overall, 2,6-dimethylpyrazine and trimethylpyrazine were found by a high proportion in all samples. Tetramethylpyrazine, a main flavor of doenjang, a Korean fermented seasoning soybean paste, was identified as one of the major compounds in TMP, SPP, and SBP. SBP had benzaldehyde, hexanal, n-pentanal, and aldehydes and SPP with pyrazines.

• Journal of Microbiology and Biotechnology
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• v.8 no.5
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• pp.455-460
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• 1998

In the course of screening for new antitumor substances, a novel cytotoxic agent inducing apoptotic cell death was isolated from the culture broth of marine bacterial strain SCRC A-20. Strain SCRC A-20 was separated from a mollusk and was chemotaxonomically identified as a Streptomyces sp. The cytotoxic substance was purified by organic solvent extraction followed by silica gel column chromatography and preparative TLC. HRFAB-MS determined its molecular formula to be $C_{30}H_{40}N_2O_5$ (MW 508). The 1D and 2D NMR spectral data demonstrated that the substance has a novel lactam structure of a 20-membered macrocycle coupled with a unique acyl tetramine and bicyclo［3.3.0］ octane, which includes three methyl groups, six olefinic protons, five carbonyl groups, a conjugated diene and a dienone. The substance, named aburatubolactam C, appeared to be cytotoxic for various continuously proliferating tumor cells of human and murine origins. The $IC_{50}$ values determined by MIT assay were in the range of 0.3 to $5.8\mug/ml$. When Jurkat T cells were treated with $3\mug/ml$. of aburatubolactam C, the apoptotic DNA fragmentation was detectable within 3 h, indicating that the cytotoxic effect of aburatubolactam C on tumor cells is attributable to the induced apoptosis.

• Journal of Microbiology and Biotechnology
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• v.18 no.10
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• pp.1659-1662
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• 2008

Pseudomonas chlororaphis O6 exhibits induced systemic resistance (ISR) against P. syringae pv. tabaci in tobacco. To identify one of the ISR metabolites, O6 cultures were extracted with organic solvents, and the organic extracts were subjected to column chromatography followed by spectroscopy analyses. The ISR bioassay-guided fractionation was carried out for isolation of the metabolite. High-resolution mass spectrometric analysis of the metabolite found $C_{9}H_{9}O_{3}N$ with an exact mass of 179.0582. LC/MS analysis in positive mode showed an $(M+H)^{+}$ peak at m/z 180. Nuclear magnetic resonance ($^{1}H,\;^{13}C$) analyses identified all protons and carbons of the metabolite. Based on the spectroscopy data, the metabolite was identified as 4-(aminocarbonyl) phenylacetate (4-ACPA). 4-ACPA applied at 68.0 mM exhibited ISR activity at a level similar to 1.0 mM salicylic acid. This is the first report to identify an ISR metabolite produced by P. chlororaphis O6 against the wildfire pathogen P. syringae pv. tabaci in tobacco.

• Bulletin of the Korean Chemical Society
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• v.26 no.11
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• pp.1757-1760
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• 2005

A series of 6-alkyloxyl-3,4-dihydro-2(1H)-quinoliones (5a-5n) were synthesized through nitration, reduction, diazotization, hydrolysis and alkylation from 3,4-dihydro-2(1H)-quinolione. Their structures were characterized by IR, $^1H$-NMR and MS. The anticonvulsant activity was evaluated by the Maximal electroshock test (MES) and the subcutaneous pentylenetetrazole (Metrazole) test (sc-Met). The neurotoxicity was measured by the Rotarod test (Tox). The result showed that 6-hexyloxy-3,4-dihydro-2 (1H)-quinolinone (5c) was potent in anti-MES and anti-scMet test with $ED_{50}$ of 24.0 mg/kg and 21.2 mg/kg, respectively, albeit its $TD_{50}$ (67.6 mg/kg) revealed the high neurotoxicity. 6-Benzyloxy-3,4-dihydro-2(1H)-quinolinone (5f) was less effective against MES induced seizure with $ED_{50}$ of 29.6 mg/kg, but no neurotoxicity was observed even under 300 mg/kg. Its Protective index (PI) was greater than 10 preferable to Phenytoin, Carbamazepin, Phenobarbital and Valproate.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.31 no.1
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• pp.41-45
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• 2020

Objective: The objective of this study was to assess serum, hair, and urinary magnesium (Mg) levels in children with attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorder (ASD), and both ASD and ADHD to reveal potential interactive effects. Methods: A total of 148 boys aged 4-9 years old were enrolled in this study, including 44 children with ADHD, 40 pediatric patients with ASD, 32 patients with both ADHD and ASD, as well as 32 healthy neurotypical children. Hair, serum, and urinary Mg levels were assessed using inductively-coupled plasma mass spectrometry (ICP-MS). Laboratory quality control was performed using certified reference materials of human hair, plasma, and urine. Results: No significant group difference in serum Mg levels was observed. Mg content in hair was found to be reduced in children with ADHD and ADHD+ASD compared to that in healthy controls by 11% and 15%, respectively. Urinary Mg levels in children with ADHD+ASD exceeded the control, ADHD, and ASD values by 51, 76, and 65%, respectively. Factorial analysis revealed significant contribution of ADHD to hair and urinary Mg levels. Multiple regression analysis demonstrated that hair and urinary Mg levels were considered as significant predictors of neurodevelopmental disorder complexity. Conclusion: We propose that impaired Mg status may provide a link between ADHD and ASD.