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

• Korean Journal of Food Science and Technology
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• v.39 no.1
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• pp.94-98
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• 2007

Ethyl carbamate, which is also known as a possible human carcinogen, is formed by ethanolysis of N-carbamyl compounds such as carbamyl phosphate, urea, or citrulline. NaCl that is highly present in fermented foods was suspected to have an influence on ethyl carbamate formation. This study was designed to determine the effect of NaCl on the chemical reactions upon incubation of ethanol with the N-carbamyl compound in a 25% NaCl solution or in the absence of NaCl, and to find a possible association with the formation of ethyl carbamate. While the amount of ethyl carbamate formed in a urea solution with the addition of NaCl was increased up to 26%, the amount formed with citrulline or carbamyl phosphate in the presence of NaCl was decreased up to 30% and 40%, respectively. This indicates that NaCl should be considered as a potential factor influencing the rate of ethyl carbamate formation from its precursors.

• Environmental Analysis Health and Toxicology
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• v.14 no.3
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• pp.113-120
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• 1999

Fluorination of drinking water has been used world widely to reduce the incidence of caries. Recently, contradictory results on the cytotoxicity of fluoride compounds are reported. In addition, there are attempts to use fluorosilicate for fluorination of drinking water in Korea, therefore, we tried to analyze the cytotoxicity of fluoride compounds on oral epidermoid carcinoma (KB and A253) and osteosarcoma (HOS and MG-63) cells in this study. We treated cells with 0, 10, 50 and 250 ppm of fluorosilicic acid (domestic or from Fluka, F$\_$6/H$_2$Si), sodium fluorosilicate (F$\_$6/Na$_2$Si), sodium fluoroacetate (FCH$_2$CO$_2$Na), sodium fluoride (NaF) or potassium fluoride(KF) and measured the relative cell survival by MTT assay. At the concentration of < 10ppm, no significant cytotoxicity was observed. At 50 ppm, each cells revealed different response to fluoride treatment. Among cells used in this study, MG-63 was the most resistant to fluoride treatment. Comparable toxicity data from domestic and imported fluorosilicic acids were obtained. When we compared the relative cytotoxicity of fluoride compounds against their fluoride contents, the differences in relative cell survival were smaller. Most of cells showed < 20% of survival at 250 ppm. In order to analyze the pH dependence of the cytotoxicity of fluorosilicates, the pH of cell culture media containing fluorosilicate was adjusted to 7.4 or 6.5 and the relative cytotoxicity was measured. At lower pH, about 10% higher cytotoxicity was obtained. Thus, our data suggested that the toxicity of domestic fluorosilicic acid was similar to that of fluorosilicic acid from Fluka, and the cytotoxicity of fluoride compounds was dependent on the relative content of fluoride and pH.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.4
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• pp.629-634
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• 2000

The effects of gamma irradiation on changes of chemical compounds of fermented shromp with low salt were studied. The shirmp was salted NaCl concentration of 10%, 15% and 20%, and irradiated at 0, 2.5, 5.0, 7.5 and 10.0kGy. Amino nitrogen (AN), volatile basic nitrogen (VBN), trimethylamine (TMA) and neutral protease acivity were examined during ferentation at 15$^{\circ}C$. A sample with 30% salt concontration was also prepared as a control. The initial contents of AAN, VBN, TMA and protease acitivity were not affected by gamma irradiation. The contents of AN, VBN and TMA were incteased with fermentation period. But, the more increased NaCl concentrations and the higher irradiation dose, the loss increased content of chemical compounds and protease activity were found. Protease was increased until 4~5 weeks and then decreased gradually. The results showed that the chemical compounds and protease activity of salted abd fermeted shrimp prepared with 15% NaCl contentration and 10 kGy irradiation dose, or 20% and 5 kGy or higher were maintained the appropriate level of quality up to 10 weeks of storage compared with the control.

• Bulletin of the Korean Chemical Society
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• v.33 no.8
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• pp.2619-2622
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• 2012

Bromination and iodination of the aromatic compounds have efficiently been carried out at room temperature and $70^{\circ}C$, respectively, in short reaction times using orthoperiodic acid/sodium bromide (1:2) and orthoperiodic acid/sodium iodide (1:2) in water to prepare the corresponding halo compounds with excellent yields.

• Bulletin of the Korean Chemical Society
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• v.24 no.11
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• pp.1664-1670
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• 2003

$NaBH_4$ with catalytic amounts of $MoCl_5$ can readily reduce a variety of carbonyl compounds such as aldehydes, ketones, acyloins, ${\alpha}$-diketones and conjugated enones to their corresponding alcohols in good to excellent yields. Reduction reactions were performed under aprotic condition in $CH_3CN$ at room temperature or reflux. In addition, the chemoselective reduction of aldehydes over ketones was accomplished successfully with this reducing system.

• Journal of Environmental Health Sciences
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• v.25 no.3
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• pp.103-107
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• 1999

Even if odorous compounds remain very low concentration in water, it cause strong odor. Because Geosmin and most of odorous compound had very low vaporization, those were difficult to analyze with GC/MSD and Purge & Trap. So, we needed pre-treatment method for decreasing amounts of extracting solvents, improving recovery efficiencies and increasing analytical efficiencies. This study developed efficient technology for analyzing odorous compounds, using various adsorbents and extracting solvents. The optimum adsorbent was XAD resins. Especially, XAD-2, XAD-7 and XAD-2010 were superior, but XAD-2 of these and the optimum extraction solvent is MTBE. Other extraction solvents' efficiency is in order of MTBE>Dichloromethane>n-Hexane>Diethylether. The optimum NaCl dosage for increasing efficiency is 5 g in liquid-liquid extraction method. The shaking time(0~24hr) has no concern with adsorption efficiency. The optimum adsorbent is XAD-2 resin and extraction solvent is MTBE. Dosing NaCl, adsorption efficiency is increased in liquid-liquid extraction method, but NaCl has no effect on liquid-solid extraction method. In this experimental results, this algae toxins(Mycrocystin, Anatoxin etc.).

• Journal of Integrative Natural Science
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• v.8 no.3
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• pp.209-213
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• 2015

Influenza A virus (H1N1) causes and spreads infectious diseases and becomes a major health threat in humans. Among the subtypes of influenza virus, neuraminidase (NA) plays an important role in viral life cycle and becomes an attractive therapeutic target. Currently two NA inhibitors namely Zanamivir and Oseltamivir are available for treating infectious diseases. Recently five naturally derived polyphenols extracted from Phellinus baumii was reported as inhibitors against NA. Molecular docking is powerful tool in computer aided drug designing which aids in exploring and elucidating the properties of the molecules from their 3D structure. Hence, in the present study, molecular docking was carried out on reported polyphenols isolated from ethanolic extract of fruiting bodies of Phellinus baumii. The objective of this work was to study the interaction and to propose the binding mode of these compounds within the binding site of H1N1 neuraminidase. The results showed these compounds had better binding energy and H-bond interactions with the important active site residues of the receptor which authenticate these compounds contributes to inhibitory activity of neuraminidase to treat influenza infection.

• Food Science and Biotechnology
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• v.14 no.2
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• pp.238-241
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• 2005

Aroma-active compounds were evaluated from salt-fermented anchovy sauce by solid phase microextraction-gas chromatography-olfactometry (SPME-GC-O) based on sample dilution analysis (SDA). SPME extract from carboxen/polydimethylsiloxane (CAR/PDMS) fiber was the most similar to the original odor of salt-fermented anchovy sauce used for this experiment, followed by divinylbenzene/CAR/PDMS (DVB/CAR/PDMS) fiber. Because salt-fermented anchovy sauce contains 23% NaCl, NaCl concentration of diluent was considered when salt-fermented anchovy sauce was serially diluted. Linear relationship between GC response and sample concentration was observed when diluted with 23% NaCl solution, whereas not observed when diluted with deodorized distilled water. Eleven and 16 aroma-active compounds were detected by SPME-GC-O based on SDA using CAR/PDMS and DVB/CAR/PDMS fibers, respectively. Butanoic acid and 3-methyl butanoic acid showed the highest ${\log}_2SD$ factors for CAR/PDMS and DVB/CAR/PDMS fibers. Dimethyl trisulfide, methional, trimethyl amine, 1-penten-3-ol, and acetic acid were also detected as potent aroma-active compounds.

• Genomics & Informatics
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• v.14 no.3
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• pp.96-103
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• 2016

The influenza A (H1N1) virus, also known as swine flu is a leading cause of morbidity and mortality since 2009. There is a need to explore novel anti-viral drugs for overcoming the epidemics. Traditionally, different plant extracts of garlic, ginger, kalmegh, ajwain, green tea, turmeric, menthe, tulsi, etc. have been used as hopeful source of prevention and treatment of human influenza. The H1N1 virus contains an important glycoprotein, known as neuraminidase (NA) that is mainly responsible for initiation of viral infection and is essential for the life cycle of H1N1. It is responsible for sialic acid cleavage from glycans of the infected cell. We employed amino acid sequence of H1N1 NA to predict the tertiary structure using Phyre2 server and validated using ProCheck, ProSA, ProQ, and ERRAT server. Further, the modelled structure was docked with thirteen natural compounds of plant origin using AutoDock4.2. Most of the natural compounds showed effective inhibitory activity against H1N1 NA in binding condition. This study also highlights interaction of these natural inhibitors with amino residues of NA protein. Furthermore, among 13 natural compounds, theaflavin, found in green tea, was observed to inhibit H1N1 NA proteins strongly supported by lowest docking energy. Hence, it may be of interest to consider theaflavin for further in vitro and in vivo evaluation.