• Korean Journal of Food Science and Technology
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• v.42 no.1
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• pp.8-13
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• 2010

Bisphenol A diglycidyl ether (BADGE) and bisphenol F diglycidyl ether (BFDGE) were obtained by a polymerization reaction of epichlorohydrin (ECH) with bisphenol A (BPA) or bisphenol F (BPF). These compounds are commonly used as monomers or additives such as a polymerization stabilizer and a hydrochloric acid scavenger of epoxy resin, polyvinyl chloride (PVC)-containing organosols and polyester lacquers, that are applied to the internal surface of most canned foods to impart chemical resistance. The unreacted BADGE, BFDGE and their reaction products migrating from epoxy resin, PVC-containing organosol and/or polyester lacquer-based food packaging materials into the foods have recently become an issue of great concern because of increased customer demand for safety. This study was conducted to develop a rapid and sensitive simultaneous analysis method based on HPLC/FLD and HPLC/APCI-mass and to evaluate the concentration of BADGE, BFDGE and their metabolites, BADGE $H_2O$, BADGE $2H_2O$, BADGE HCl, BADGE 2HCl, BADGE HCl $H_2O$, BFDGE $H_2O$, BFDGE $2H_2O$, BFDGE HCl, BFDGE 2HCl and BFDGE HCl $H_2O$ for 133 canned food samples. The method provided a linearity of 0.9997-0.9999, a limit of detection of $0.01-0.13\;{\mu}g/mL$, a limit of quantitation of $0.03-0.44\;{\mu}g/mL$ and a recovery (%) of 85.64-118.18. The number of samples containing BADGE, BFDGE or their metabolites were: 28/133 (21.1%), with levels of 0.400-0.888 mg/kg being observed for aqueous foods (19/133) and 0.093-0.506 mg/kg being observed for oily foods (9/133).

• Culinary science and hospitality research
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• v.20 no.3
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• pp.37-49
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• 2014

In order to elucidate the usefulness of Lycopene, a cherry tomato variety, as a food material, the compositions of free amino acids, amino acid metabolites and polyphenol compounds were analyzed using HPLC and LC-MS/MS method. Lycopene contained eighteen free amino acids except for L-Cys and L-Try. L-Glu was the most abundant free amino acid, followed by L-Gln and L-Asp. The percentages of L-Glu, L-Gln and L-Asp of total free amino acid were 55.5%, 15.9% and 9.9% respectively. Lycopene contained essential amino acids with the exception of tryptophan. The following amino acid metabolites were found : ${\gamma}$-aminobutyric acid(GABA), carnitine(L-Car), o-phosphoethanolamine(o-Pea), hydroxylysine(Hyl) phosphoserine (p-Ser), N-methyl-histidine(Me-His), ethanolamine($EtNH_2$). Especially, GABA known as a neurotransmitter was present at a high level(305.99 mg/100 g dry weight). We identified the following polyphenol compounds in the cherry tomatoes : caffeic acid-hexose isomer I (CH I), caffeic acid-hexose isomer II (CH II), 3-caffeoylquinic acid(3-CQA), 5-caffeoylquinic acid(5-CQA), caffeoylquinic acid isomer(CQAI), quercetin-hexose-deoxyhexose-pentose(QTS), quercetin-3-rutinoside(Q-3-R), di-caffeoylquinic acid(di-CQA), tri-caffeoylquinic acid(tri-CQA), naringenin chalcone(NGC). Large quantities of Q-3-R and NGC known as bioactive compounds were found. These results revealed that Lycopene variety contained various nutritional and bioactive compounds and would be a potent functional food material.

• Journal of Ginseng Research
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• v.44 no.3
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• pp.461-474
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• 2020

Background: Ginseng effectively reduces fatigue in both animal models and clinical trials. However, the mechanism of action is not completely understood, and its molecular targets remain largely unknown. Methods: By screening for proteins that interact with the primary components of ginseng (ginsenosides) in an affinity chromatography assay, we have identified muscle-type creatine kinase (CK-MM) as a potential target in skeletal muscle tissues. Results: Biolayer interferometry analysis showed that ginsenoside metabolites, instead of parent ginsenosides, had direct interaction with recombinant human CK-MM. Subsequently, 20(S)-protopanaxadiol (PPD), which is a ginsenoside metabolite and displayed the strongest interaction with CK-MM in the study, was selected as a representative to confirm direct binding and its biological importance. Biolayer interferometry kinetics analysis and isothermal titration calorimetry assay demonstrated that PPD specifically bound to human CK-MM. Moreover, the mutation of key amino acids predicted by molecular docking decreased the affinity between PPD and CK-MM. The direct binding activated CK-MM activity in vitro and in vivo, which increased the levels of tissue phosphocreatine and strengthened the function of the creatine kinase/phosphocreatine system in skeletal muscle, thus buffering cellular ATP, delaying exercise-induced lactate accumulation, and improving exercise performance in mice. Conclusion: Our results suggest a cellular target and an initiating molecular event by which ginseng reduces fatigue. All these findings indicate PPD as a small molecular activator of CK-MM, which can help in further developing better CK-MM activators based on the dammarane-type triterpenoid structure.

• Journal of Life Science
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• v.28 no.8
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• pp.917-922
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• 2018

Centella asiatica is one of the local herbs that is claimed to possess various physiological effects. C. asiatica also accumulates large amounts of pentacyclic triterpenoid saponins known as centelloids. These terpenoids usually include asiatic acid, asiaticoside, madecassoside, and madecassic acids. In the present study, to understand the changes of triterpene glycoside levels in the different shoot tissues of C. asiatica during seasonal cultivation, we investigated the High-Performance Liquid Chromatography (HPLC) analysis via different extraction methods, such as water, 20% ethanol and methanol extracts. Significant increases were observed in the levels of madecassoside and asiaticoside in the leaf extracts by methanol compare with extracts using water or 20% ethanol. Additionally, we also analyzed the various antioxidant activity in the different shoot tissues of C. asiatica using different extracts, such as leaves, petioles and both materials. Among these petiole extracts showed high 2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTs) scavenging activity in all extracts, whereas 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity exhibited high activity levels in the leaf part using methanol and ethanol extracts. Levels of total phenolics and flavonoid also showed the highest levels in the leaf tissues using all extracts such as methanol, ethanol and water. Our results indicated that the increased levels of triterpene glycoside and antioxidant activity in the leaf parts of the C. asiatica were indicating that useful metabolites were mainly maintained through seasonal cultivation such as madecassoside, asiaticoside.

• The Plant Pathology Journal
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• v.33 no.5
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• pp.488-498
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• 2017

The aim of this study was to identify volatile and agardiffusible antifungal metabolites produced by Bacillus sp. G341 with strong antifungal activity against various phytopathogenic fungi. Strain G341 isolated from four-year-old roots of Korean ginseng with rot symptoms was identified as Bacillus velezensis based on 16S rDNA and gyrA sequences. Strain G341 inhibited mycelial growth of all phytopathogenic fungi tested. In vivo experiment results revealed that n-butanol extract of fermentation broth effectively controlled the development of rice sheath blight, tomato gray mold, tomato late blight, wheat leaf rust, barley powdery mildew, and red pepper anthracnose. Two antifungal compounds were isolated from strain G341 and identified as bacillomycin L and fengycin A by MS/MS analysis. Moreover, volatile compounds emitted from strain G341 were found to be able to inhibit mycelial growth of various phytopathogenic fungi. Based on volatile compound profiles of strain G341 obtained through headspace collection and analysis on GC-MS, dimethylsulfoxide, 1-butanol, and 3-hydroxy-2-butanone (acetoin) were identified. Taken together, these results suggest that B. valezensis G341 can be used as a biocontrol agent for various plant diseases caused by phytopathogenic fungi.

• The Korean Journal of Pesticide Science
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• v.4 no.1
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• pp.1-10
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• 2000

The purpose of this study is to establish the assessment techniques of hazardous chemicals by the development of analytical method of biological samples. In this study, we have developed an extraction method of nine pesticides used for rice paddy that resulted in high recovery from the spiked human urine by the liquid-liquid extraction with diethyl ether at pH 7.0. Calibration curve obtained from each pesticide standard using by gas chromatography/mass spectrometry/selected ion monitoring has shown good linearity and detection limits were the range of $0.4{\sim}2.0$ ng/mL in urine. As a biological monitoring, urine samples of local farmers exposed directly to nine pesticides in the field were collected and analyzed by GC/MS. Of the tested pesticides, metabolites of phenthoate assumed were identified by GC/MS analysis. No parent compound was detected.

• Journal of Microbiology and Biotechnology
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• v.28 no.2
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• pp.199-209
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• 2018

Volatile organic compounds (VOCs) are increasingly been recognized as the chemical mediators of mold interactions, shaping their community dynamics, growth, and metabolism. Herein, we selectively examined the time-correlated (0 D-11 D, where D = incubation days) effects of intraspecies VOC-mediated interactions (VMI) on Aspergillus oryzae KCCM 60345 (S1), following co-cultivation with partner strain A. oryzae KACC 44967 (S2), in a specially designed twin plate assembly. The comparative evaluation of $S1_{VMI}$ (S1 subjected to VMI with S2) and its control ($S1_{Con}$) showed a notable disparity in their radial growth ($S1_{VMI}$ < $S1_{Con}$) at 5 D, protease activity ($S1_{VMI}$ > $S1_{Con}$) at 3-5 D, amylase activity ($S1_{VMI}$ < $S1_{Con}$) at 3-5 D, and antioxidant levels ($S1_{VMI}$ > $S1_{Con}$) at 3 D. Furthermore, we observed a distinct clustering pattern for gas chromatography-time of flight-mass spectrometry datasets from 5 D extracts of $S1_{VMI}$ and $S1_{Con}$ in principle component analysis (PC1: 30.85%; PC2: 10.31%) and partial least squares discriminant analysis (PLS-DA) (PLS1: 30.77; PLS2: 10.15%). Overall, 43 significantly discriminant metabolites were determined for engendering the metabolic variance based on the PLS-DA model (VIP > 0.7, p < 0.05). In general, a marked disparity in the relative abundance of amino acids ($S1_{VMI}$ > $S1_{Con}$) at 5 D, organic acids ($S1_{VMI}$ > $S1_{Con}$) at 5 D, and kojic acid ($S1_{VMI}$ < $S1_{Con}$) at 5-7 D were observed. Examining the headspace VOCs shared between S1 and S2 in the twin plate for 5 D incubated samples, we observed the relatively higher abundance of C-8 VOCs (1-octen-3-ol, (5Z)-octa-1,5-dien-3-ol, 3-octanone, 1-octen-3-ol acetate) having known semiochemical functions. The present study potentially illuminates the effects of VMI on commercially important A. oryzae's growth and biochemical phenotypes with subtle details of altered metabolomes.

• Korean Journal of Biological Psychiatry
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• v.18 no.2
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• pp.95-100
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• 2011

Objectives To evaluate the drug interactions between aripiprazole and haloperidol, authors investigated plasma concentrations of those drugs by genotypes. Method Fifty six patients with a confirmed Diagnostic and Statistical Manual of Mental Disorders 4th edition diagnosis of schizophrenia were enrolled in this eight-week, double blind, placebo-controlled study. Twenty-eight patients received adjunctive aripiprazole treatment and twenty-eight patients received placebo while being maintained on haloperidol treatment. Aripiprazole was dosed at 15 mg/day for the first 4 weeks, and then 30 mg for the next 4 weeks. The haloperidol dose remained fixed throughout the study. Plasma concentrations of haloperidol and aripiprazole were measured by high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) at baseline, week 1, 2, 4 and 8. $^*1$, $^*5$, and $^*10$ B alleles of CYP2D6 and $^*1$ and $^*3$ alleles of CYP3A5 were determined. The Student's T-test, Pearson's Chi-square test, Wilcoxon Rank Sum test and Logistic Regression analysis were used for data analysis. All tests were two-tailed and significance was defined as an alpha < 0.05. Results In the frequency of CYP2D6 genotype, $^*1/^*10$ B type was most frequent (36.5%) and $^*1/^*1$ (30.8%), $^*10B/^*10B$ (17.3%) types followed. In the frequency of CYP3A5 genotype, $^*3/^*3$ type was found in 63.5% of subjects, and $^*1/^*3$ type and $^*1/^*1$ were 30.8% and 5.8% respectively. The plasma levels of haloperidol and its metabolites did not demonstrate significant time effects and time-group interactions after adjunctive treatment of aripiprazole. The genotypes of CYP2D6 and 3A5 did not affect the plasma concentration of haloperidol in this trial. No serious adverse event was found after adding aripiprazole to haloperidol. Conclusion No significant drug interaction was found between haloperidol and aripiprazole. Genotypes of CYP2D6 and 3A5 did not affect the concentration of haloperidol after adding aripiprazole.

• Journal of Plant Biotechnology
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• v.42 no.3
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• pp.186-195
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• 2015

Anthranilate synthase (AS) is a key enzyme in the biosynthesis of tryptophan (Trp), which is the precursor of bioactive metabolites like indole-3-acetic acid and other indole alkaloids. Alpha anthranilate synthase 2 (OsASA2) plays a critical role in the feedback inhibition of tryptophan biosynthesis. In this study, two vectors with single (F124V) and double (S126F/L530D) point mutations of the OsASA2 gene for feedback-insensitive ${\alpha}$ subunit of rice anthranilate synthase were constructed and transformed into wildtype Dongjinbyeo by Agrobacterium-mediated transformation. Transgenic single and double mutant lines were selected as a single copy using TaqMan PCR utilized nos gene probe. To select intergenic lines, the flanking sequence of RB or LB was digested with a BfaI enzyme. Four intergenic lines were selected using a flanking sequence tagged (FST) analysis. Expression in rice (Oryza sativa L.) of the transgenes resulted in the accumulation of tryptophan (Trp), indole-3-acetonitrile (IAN), and indole-3-acetic acid (IAA) in leaves and tryptophan content as a free amino acid in seeds also increased up to 30 times relative to the wildtype. Two homozygous event lines, S-TG1 and D-TG1, were selected for characterization of agronomic traits and metabolite profiling of seeds. Differentially expressed genes (DEGs), related to ion transfer and nutrient supply, were upregulated and DEGs related to co-enzymes that work as functional genes were down regulated. These results suggest that two homozygous event lines may prove effective for the breeding of crops with an increased level of free tryptophan content.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.36-36
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• 2017

Out of twenty common protein amino acids, there are many kinds of non protein amino acids (NPAAs) that exist as secondary metabolites and exert ecological functions in plants. Mimosine (Mim), one of those NPAAs derived from L. leucocephala acts as an iron chelator and reversely block mammalian cell cycle at G1/S phases. Cysteine (Cys) is decisive for protein and glutathione that acts as an indispensable sulfur grantor for methionine and many other sulfur-containing secondary products. Cys biosynthesis includes consecutive two steps using two enzymes-serine acetyl transferase (SAT) and O-acetylserine (thiol)lyase (OASTL) and appeared in plant cytosol, chloroplast, and mitochondria. In the first step, the acetylation of the ${\beta}$-hydroxyl of L-serine by acetyl-CoA in the existence of SAT and finally, OASTL triggers ${\alpha}$, ${\beta}$-elimination of acetate from OAS and bind $H_2S$ to catalyze the synthesis of Cys. Mimosine synthase, one of the isozymes of the OASTLs, is able to synthesize Mim with 3-hydroxy-4-pyridone (3H4P) instead of $H_2S$ for Cys in the last step. Thus, the aim of this study was to clone and characterize the cytosolic (Cy) OASTL gene from L. leucocephala, express the recombinant OASTL in Escherichia coli, purify it, do enzyme kinetic analysis, perform docking dynamics simulation analysis between the receptor and the ligands and compare its performance between Cys and Mim synthesis. Cy-OASTL was obtained through both directional degenerate primers corresponding to conserved amino acid region among plant Cys synthase family and the purified protein was 34.3KDa. After cleaving the GST-tag, Cy-OASTL was observed to form mimosine with 3H4P and OAS. The optimum Cys and Mim reaction pH and temperature were 7.5 and $40^{\circ}C$, and 8.0 and $35^{\circ}C$ respectively. Michaelis constant (Km) values of OAS from Cys were higher than the OAS from Mim. Inter fragment interaction energy (IFIE) of substrate OAS-Cy-OASTL complex model showed that Lys, Thr81, Thr77 and Gln150 demonstrated higher attraction force for Cys but 3H4P-mimosine synthase-OAS intermediate complex showed that Gly230, Tyr227, Ala231, Gly228 and Gly232 might provide higher attraction energy for the Mim. It may be concluded that Cy-OASTL demonstrates a dual role in biosynthesis both Cys and Mim and extending the knowledge on the biochemical regulatory mechanism of mimosine and cysteine.