• Microbiology and Biotechnology Letters
• /
• v.18 no.3
• /
• pp.233-238
• /
• 1990

The mechanism of intracellular accumulation of cadmium in a cadmium-ion tolerant yeast, Hansenula ammala B-7, which is an extreme cadmium tolerant strain and has the ability to take up a large amount of cadmium was investigated. The amounts of cadmium taken up by the scalded yeast cells were 2 to 3 times more than the value of the living cells. The living Hansenula anomala B-7 cells adsorbed 74% of cadmium taken up onto the other layer of the cells and 26% of it accumulated inside the cells. But the scalded cells adsorbed 98.3% of cadmium taken up and accumulated 1.7% of it inside the cells. A cadmium uptake and its accumulation were accelerated up to 162.3% and 275.4% by Triton X-100 in the living cells, respectively. Whereas in the scalded cell cadmium uptake was not affected by Triton X-100. Furthermore the cadmium uptake and its accumulation were strongly inhibited by metabolic inhibitors like 2,4-dinitrophenol, sodium azide and potassium cyanide in the living cells, but in the scalded cells cadmium uptake was not affected by metabolic inhibitors. These results suggested that the intracellular accumulation of cadmium by the cadmium-tolerant Hansenula anomala B-7 cells was apparently dependent of biological activity, and also gave evidence of the existance of energy-dependent system.

• Journal of the Korean Chemical Society
• /
• v.57 no.5
• /
• pp.612-617
• /
• 2013

The versatile, hitherto unreported 3-(4-(2-phenyldiazenyl)-2-oxo-2H-chromen-3-yl)-3-oxopropanenitrile 3 was prepared by two convenient routes: either by the reaction of ethyl 4-(2-phenyldiazenyl)-2-oxo-2H-chromen-3-carboxylate 2 with acetonitrile in the presence of sodium hydride or by treatment of 4-(2-phenyldiazenyl)-3-(2-bromoacetyl)-2H-chromen-2- one 5 with potassium cyanide. Reaction of 3 with heterocyclic diazonium salts 6, 7, 14 and 17 furnished the corresponding hydrazones 8, 9, 15 and 18. The latter hydrazones underwent intramolecular cyclization into the corresponding pyrazolo[5,1- c]-1,2,4-triazine 10, 1,2,4-triazolo[5,1-c]-1,2,4-triazine 11, 1,2,4-triazino[4,3-b]indazole 16 and imidazo[2,1-c]-1,2,4-triazine 19 derivatives, respectively upon refluxing in pyridine.

• Journal of Plant Biology
• /
• v.2 no.1
• /
• pp.1-12
• /
• 1959

1) The comparative studies of the quantitative measurement of growth characteristics and utilization of substrates by Euglena gracilis var. bacilla 10616 in the light and in darkness have been carried out. Eodogenous respiration, effect of respiratory inhibitors and responses to the added substrates for the exogenous respiration are also investigated. 2) All cultures are grown in the open air under the continuous illumination of fluorescent light of 3500 lux at room termperature, the growth rate of the culture in the basal medium added 0.5% lactate is found to be the highest. The growth rate decreases successively for the cultures of 0.5% sucinate, 0.5% Na-acetate, 0.5% malate, and control. There is no growth in the basal meidum added 0.5% butyrate and 0.5% hydroquinone. The similar results are obtained for the mentioned cultures in the darkness. However, the growth rate in basal medium added 0.5% glucose and 0.5% sucrose does seem to increase in the darkness unlike the illumination. 3) The endogenous rate of respiration for the organism cultured photosynthetically is about 12.94ul 02/mg/hr, in basal medium and the respiratory quotient is about 0.84. The rate is decreased by starvations to 6.5ul 02/mg/hr, about to a half, but the respiratory quotient does net change. 4) The oxygen consomption during initial 2 hours in suspending solution ranging from pH 4.5 to pH 9.3 is highest at pH 4.5 in which the algae had grown, at pH 5.5 and at pH 6.9. 5) Endogenous respiration of the cells is strongly inhibited by 0.1M of potassium cyanide, malomic acid, sodium fluoride and iodo-acetic acid. It is also strongly inhibited by 0.01M of potassium cyanide. 6) The respiratory response to added substrates for the exogenous respiration in the organism is coincided with the rate in the basal medium added the substrate in light and in darkness, whether the cells are fed or starved. 7) According to the results of this study, there seems to be the flexibility of the interconversion between photosynthesis and chemosynthesis, heterotropic mode of metabolism, in Euglena gracilis var. bacillaris, and that this organism utilizes the lactate most. It also may be suggested that the enayme systems linked in the each steps of Embden-Myerhof-Parnas path way and TCA cycle seem to exist in this organism.

• Clean Technology
• /
• v.5 no.1
• /
• pp.20-29
• /
• 1999

In the treatment of Cu - and CN - contained wastewater by using Fenton oxidation-flocculation-precipitation, the optimal removal efficiencies of the cyanide and copper were investigated according to pH, reaction time, the molar ratio of cyanide and hydrogen peroxide and the mass ratio of ferrous sulfate and hydrogen peroxide for Fenton oxidation, and pH for hydroxide precipitation, respectively. As a result, the $CN^-$ removal efficiency in our experimental wastewater by the Fenton oxidation was 81.2%~99% at its optimal conditions of pH ranging from 3 to 5 and reaction time of 30 minutes. And the optimal dosage of hydrogen peroxide and ferrous sulfate was 214, $428mg/{\ell}$, 107, $161mg/{\ell}$, 214, $214mg/{\ell}$ and 520, $500mg/{\ell}$, respectively when the molar ratio of $Cu^{2+}$:CN is 2:1, 1:1, 1:2, 1:10, and was 900, $1050mg/{\ell}$ when the molar ratio of $Cu^+$: CN is 1:10. When the copper was precipitated by sodium hydroxide after Fenton oxidation, the copper removal efficiency in the wastewater at pH 7 was 98.92%, 98.52%, 92.46%, 90.6% and 95%, respectively.

• Proceedings of the Ginseng society Conference
• /
• 1984.09a
• /
• pp.257-275
• /
• 1984

Enzymatic browning is considered desirable in tea and tobacco processing but undesirable in many fruits processing at the present time. It is necessary to understand the nature of the enzyme, phenoloxidase, in order to control browning reactions, and extend its effects to formation of browning products as antioxidants in ginseng. Ginseng exhibits antioxidant activity when incorporated with turkey dark meat patties. The activity in red ginseng showed about two times stronger than white ginseng. One of the phenolic antioxidants from fresh, white and reprocessed white ginseng was identified as phenol 2.6 Bis(1.1 dimethyl ethyl) 4-methyl among several unknown compounds by GC/mass spectrometer. In red ginseng, no phenol 2.6 Bis (1.1 dimethyl ethyl) 4-methyl was detected, the compound may be polymerized by phenoloxidase and form some higher molecular compounds which may possess high antioxidant activity. Phenoloxidase isozymes in fresh Korean ginseng (panax ginseng C.A. Meyer) were extracted with phosphate buffer at pH 7.3. The isozymes were purified through ammonium sulfate fractionation, dialysis and chromatography on a DEAE-cellulose column. Two groups of phenoloxidase were shown to be present, one in the floating agglomerated group and the other in the precipitate. group from the 0.85 saturation ammonium sulfate. The DEAE-cellulose column chromatography, the phenoloxidase isozyme present in the precipitate appears as the first peak (I), and that in the agglomerate in the second peak (II). Isozyme I showed higher activity with catechin and catechal, and isozyme II showed higher activity with p-cresol. The isozyme showed two optimum pH activity one at pH 4.5 and the other at 8.5 with catechin as substrate. Korean ginseng phenoloxidase has high heat stability. When heated at $75^{\circ}C$ for 2 hours, its activity remained $90\%\;and\;80\%$ on phenoloxidase I and II respectively. Phenoloxidase I was most active on (+) catechin followed by p-cresal, catechol and epicatechin. Phenoloxidase II was most active on p-cresal followed by (+) catechin, catechol, p-coumanic acid and epicatechin. Sodium bisulfite, sodium cyanide, ascorbic acid glutachion in the oxidized form, sodium diethyl dithiocarbomate and ethylendiamine tetra acetate (EDTA) acted as inhibitors. Red ginseng color development was initiated by phenoloxidase and finished by a followed sun drying process. The antiaging activity of ginseng may be initiated by the antioxidant in the ginseng.

• Herbal Formula Science
• /
• v.13 no.1
• /
• pp.35-48
• /
• 2005

Alzheimer's disease(AD) is a geriatric dementia that is widespread in old age. In the near future AD will be the biggest problem in public health service. It has been widely believed that $A{\beta}$ peptide devided from APP causes apoptotic neurotoxicity in brain. However, recent evidence suggests that n99 may be an important factor causing neurotoxicity in AD. Mouse PC12 cells expressed with n99 exhibited remarkable apoptotic cell damage. We invesgated the protective effects of Gagamgobonhwan water extract(GKG). Findings from our experiments have shown that GKG inhibits the activities of CT99, which has neurotoxicities and apoptotic activities in cell line. In addition, treatment of GKG($75{\mu}g/ml$ 24 hours) partially prevented CT99-induced cytotoxicity in PC12 cells. As the result of this study, in GKG group the apoptosis in the nervous system was inhibited, the repair against the degerneration of PC12 cells by CT99 expression is promoted. Taken together, GKG exhibited inhibition of CT99-induced apoptotic cell death. GKG may be beneficial for the treatment of AD.

• Korean Journal of Pharmacognosy
• /
• v.30 no.3
• /
• pp.306-313
• /
• 1999

Polyphenol Oxidase(PPO) was purified from an extract of Ginkgo biloba leaves by ammonium sulfate fractionation followed by sephadex G-150 column chromatography, which resulted in a 18-fold increase in specific activity. The enzyme was most active at pH 8.5 and the temperature optimum for the PPO catechol oxidation reaction was $45^{\circ}C$. Heat inactivation studies showed that heating for 7, 9 and 48 min, at 80, 70 and $60^{\circ}C$ respectively caused a 50% loss in enzymatic activity and that the enzyme was completely inactivated after heat treatment at $90^{\circ}C$ for 60 min. Km values of the PPO for catechol, hydroquinone and 4-methylcatechol derived from Lineweaver-Burk plots were $6.06\;{\times}\;10^{-4}M,\;1.02\;{\times}\;10^{-3}M,\;1.41\;{\times}\;10^{-3}M$ respectively. Of the substrates tested, 4-methylcatechol was oxidized most readily and the enzyme did not oxidize monophenols. The enzyme datalyzed browning reaction was completely inhibited in the presence of reducing reagents, namely ascorbic acid, cysteine, glutathione, 2-mercaptoethanol, potassium metabisulfite at 0.5 mM level. Sodium chloride showed very little inhibition effect on Ginkgo biloba leaves PPO. Lineweaver-Burk analysis of inhibition data revealed that the inhibition by cysteine, 2-mercaptoethanol, potassium cyanide was competitive with ki values of $1.1\;{\times}\;10^{-5}M,\;2.4\;{\times}\;10^{-5}M,\;8\;{\times}\;10^{-5}M$, respectively. Among the divalent cations, $Cu^{2+}ion$ was a strong activator on PPO and $Mn^{2+}ion$ was little or no effect on PPO activity $Ni^{2+}ion$ was an inhibitor on PPO.

• Applied Biological Chemistry
• /
• v.24 no.3
• /
• pp.167-173
• /
• 1981

Crude enzyme of polyphenol oxidase was obtained from garlic. This enzyme actively oxidized triphenols such as pyrogallol and gallic acid, although it showed very weak activity on diphenols such as catechol and chlorogenic acid among the phenolic compounds tested. The optimum pH of the enzyme was 6.5 which was slightly higher than that of the garlic itself (pH 6.0). The enzyme was stable relatively at heat treatment. Sodium metabisulfite inhibited the enzyme activity at the concentration of 1mM, and KCN, L-ascorbic acid and thiourea also inhibited the enzyme action. $Mg^{++}$ activated the enzyme activity. $Cu^{++}$ activated slightly the enzyme action at low concentration (1mM), but inhibited at high concentration (10mM).

• Journal of The Korean Society of Clinical Toxicology
• /
• v.5 no.2
• /
• pp.106-111
• /
• 2007

Purpose: Inadequate hospital stocking and unavailability of essential antidotes is a worldwide problem. The purpose of this study was to determine the adequacy of antidote stocks in Korean hospitals based on a modified version of US antidote stocking guidelines. Methods: Both written and telephone surveys to collect information on hospital demographics and antidote stocking were given to the emergency departments or hospital pharmacies of 117 hospitals with emergency medical centers. The twenty antidotes included in the survey were taken from year 2000 US antidote stocking guidelines, except for activated charcoal and black widow spider antivenin. Antidote stocks were compared by hospital size, geographic location, and type of emergency medical center. Results: Complete responses were received from all hospitals. A mean of $12.4{\pm}2.9$ antidotes were adequately stocked per hospital. All hospitals stocked atropine, $CaCl_2$ naloxone, and sodium bicarbonate. However, digoxin Fab fragment (16%), cyanide kits (15%), EDTA (10%), BAL (9%), and fomepizole (1%) were not uniformly stocked. Large and teaching hospitals were significantly more likely to stock greater numbers of antidotes. Conclusions: Korean hospitals as a group do not have adequate antidote stocks. Korean stocking guidelines and an antidote management system are recommended in order to correct these deficiencies.

• Korean Journal of Veterinary Research
• /
• v.40 no.2
• /
• pp.291-299
• /
• 2000

Magnesium ($Mg^{2+}$) transport across the plasma membrane of cardiac myocytes appears to be under hormonal control. Repeated stimulations with adrenergic or histaminergic agonist produced a progressive decrease in $Mg^{2+}$ efflux from hearts. Thus we hypothesized that the $Mg^{2+}$ efflux may be resulted from a down-regulation of receptors or from a depletion of $Mg^{2+}$ from intracellular pool(s) in the hearts. In the present study, the regulation of $Mg^{2+}$ homeostasis by receptor stimulation was studied in perfused rat and guinea pig hearts. The successive short addition of norepinephrine (NE) to rat and guinea pig, and of histamine (HT) to perfused guinea pig hearts induced a progressive decrease in $Mg^{2+}$ efflux. These $Mg^{2+}$ effluxes were blocked by propranolol or ranitidine, respectively. These decrease in $Mg^{2+}$ efflux were inhibited by sodium cyanide (NaCN), which increases intracellular $Mg^{2+}$ ($[Mg^{2+}]_i$) levels. When NE (or HT) was added after HT (or NE), this efflux was also decreased in the guinea pig hearts. In the rat hearts and myocytes, HT did not stimulate $Mg^{2+}$ efflux. But NE produced a large $Mg^{2+}$ efflux after stimulation with HT. 8-(4-Chlorophenylthio)-adenosine cAMP (cAMP), like NE and HT, also induced a progressive decrease in $Mg^{2+}$ efflux in guinea pig hearts. This effect was inhibited by NaCN. These data provide evidence that the progressive decrease in receptor-stimulated $Mg^{2+}$ efflux is considered to be due to a decrease in $[Mg^{2+}]_i$ levels rather than receptor down-regulation.