• Toxicological Research
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• v.29 no.3
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• pp.165-172
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• 2013

Acetaminophen (APAP) known as paracetamol is the main ingredient in Tylenol, which has analgesic and anti-pyretic properties. Inappropriate use of APAP causes major morbidity and mortality secondary to hepatic failure. Overdose of APAP depletes the hepatic glutathione (GSH) rapidly, and the metabolic intermediate leads to hepatocellular death. This article reviews the mechanisms of hepatotoxicity and provides an overview of current research studies. Pharmacokinetics including metabolism (activation and detoxification), subsequent transport (efflux)-facilitating excretion, and some other aspects related to toxicity are discussed. Nuclear factor erythroid 2-related factor 2 (Nrf2)-regulated gene battery plays a critical role in the multiple steps associated with the mitigation of APAP toxicity. The role of Nrf2 as a protective target is described, and potential natural products inhibiting APAP toxicity are outlined. This review provides an update on the mechanism of APAP toxicity and highlights the beneficial role of Nrf2 and specific natural products in hepatoprotection.

• Korean Journal of Pharmacognosy
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• v.27 no.2
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• pp.117-122
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• 1996

The methanolic extracts of some marine natural products were tested for investigating the effects on the formation of lipid peroxide and the activities of free radical generating enzymes. The methanolic extracts of Styela clava, Ecklonia stolonifera, Pachymeniopsis elliptica and Hypnea charoides which decreased the formation of lipid peroxide inhibited the activity of xanthine oxidase about 41, 20, 20 and 21% by adding $100\;{\mu}g/ml$ of each methanolic extracts, respectively. However, the four extracts didn't inhibit the activity of aldehyde oxidase.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.23 no.3
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• pp.122-127
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• 1997

Chitin and chitosan have been almost neglected until 1960's although they second largest biomass on earth. Chitosan is a partially deacetylated chitin and belongs to the class of cationic biopolymers. We investigated the antimicrobial activity of chitosan as natural preservatives in cosmetic products. Antimicrobial activity of chitosan against some microorganisms was investigated. The results indicated that chitosan had an effectiveness against some bacteria. We found that chitosan had minimum inhibitory concentataions as low as 100 ppm to S. aureus ATCC 6538, E. coli ATCC 1634 and P. aeruginosa KCTC 2004. But there was not effects to Asp. Niger ATCC 1374 at 1,000 ppm. Also, formuias preserved with chitosan have been subjected to preservative efficacy tests to some microorganisms. Formla preserved with 0.5% chitosan had an effective antimicrobial activity against the Gram (+) and Gram (-) bacteria but not fungi. It is possible to dertermine the formulas with chitosan, which would be effective to reduce the artificial preservatives.

• Journal of Applied Biological Chemistry
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• v.58 no.3
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• pp.209-218
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• 2015

Fructooligosaccharides have been mainly produced by microbial fructosyltransferases (FTase) enzymes. The present work focuses on the optimization of medium composition and cultivation parameters affecting FTase produced by Penicillium aurantiogriseum AUMC 5605 in shake flask cultivation. FTase production was optimized in two steps using DeMeo's fractional factorial design. A 1.46-fold increase in FTase production (105.4 U/mL) was achieved using the optimized culture medium consisting of (g/L): sucrose, 600; yeast extract, 10; $K_2HPO_4$, 5; $MgSO_4{\cdot}7H_2O$, 0.5; $(NH_4)_2SO_4$, 1.0 and KCl, 0.5. The obtained results showed that the maximum FTase enzyme activity was produced at initial cultivation pH values ranging from 6.0-6.5, at agitation speed of 200 rpm and using vegetative fungal cells as inoculum. Moreover, results showed that optimization of medium composition and some cultivation parameters resulted in an increase of about 93.7% in the enzyme activity than the nonoptimized cultivation conditions after 96 h of cultivation. Additionally, maximum production and specific production rates recorded 2340 U/L/h and 102 U/L/h/g cells, respectively.

• Archives of Pharmacal Research
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• v.19 no.2
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• pp.112-115
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• 1996

Some antioxidant phenolic compounds exhibit prooxidant activity mainly due to their abilities to reduce $Fe^{3+}\; to\; Fe^{2+}.$ Reducing ability and prooxidant activity of maltol, an antioxidant component of Korean red ginseng, were compared with those of pyrogallol. Maltol at 2 mM did not appreciably reduce$ Fe^{3+}\; to\; Fe^{2+}$ and also failed to reduce nitroblue tetrazolium. Stimulation of hydroxyl radical mediated-deoxyribose degradation by pyrogallol was maximal at 60 .mu.M. Maltol stimulated the deoxyribose degradation to a much less extent, and a similar stimulatory effect was observed at a concentration of more than 100-fold higher than that of pyrogallol. The stimulatory effect of maltol reached a plateau over 1 mM, suggesting the removal of hydroxyl radicals by excess maltol. In bleomycin-$Fe^{3+}$-DNA assay, maltol at 2 mM produced a 2.5-fold increase of the iron-bleomycin-dependent DNA degradation over the basal value, whereas pyrogallol at 10 .mu.M accelerated DNA degradation by ca. 10-fold. Furthermore, maltol inhibited $Fe^{2+}$-stimulated DNA degradation by bleomycin. These results strongly suggested that maltol is an antioxidant with little prooxidant activity.

• Korean Journal of Medicinal Crop Science
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• v.18 no.5
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• pp.291-297
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• 2010

Liriope platyphylla has been though as an useful medical plant to improve the cough, sputum, neurodegenerative disorders, obesity, and diabetes in Korea and China from old times. In order to investigate the effects of Liriope platyphylla on expression and secretion of nerve growth factor (NGF), the mRNA expression and protein secretion were detected in the neuronal cell (B35) and neuroglial cell (C6) cultured with three differences concentration (5%, 10%, 15%) of Liriope platyphylla. In MTT assay and FACS anslysis, the some death of some B35 and C6 cells were observed in 15% extract-treated group, while other groups did not induce the death. Also, the mRNA expression of NGF were significantly increased in 5% and 10% extracts treated-group. Furthermore, the NGF protein concentration in supernatant collected from cultured cells showed the very similar pattern with mRNA expression. In order to verify the activity of secreted NGF, the culture supernatant collected from B35 and C6 cells cultured with Liriope platyphylla extracts for 24 hrs were treated into undifferentiated PC12 cells, and the differentiation level of PC12 cell were also observed with microscopes. The differentiation level of PC12 cell were significantly increased depend on the dose of extract. Therefore, these results suggested that the water extracts of Liriope platyphylla may contribute the regulation of NGF expression and secretion in the neuronal cell and be considered as an excellent candidate for a neurodegenerative disease-therapeutic drug.

• Bulletin of the Korean Mathematical Society
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• v.47 no.2
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• pp.275-286
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• 2010

The algebraic structure of the natural integral cohomology operations is explored by means of examples. We decompose the generators of the groups $H^m(\mathbb{Z},\;n)$ with $2\;{\leq}\;n\;{\leq}\;7$ and $2\;{\leq}\;m\;{\leq}\;13$ into the operations of cup products, cross-cap products and compositions. Examination of these decompositions and comparison with other possible generators demonstrates the existence of relations between integral operations that have withheld formulation. The calculated groups and generators are collected in a table for practical reference.

• Proceedings of the SCSK Conference
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• 2003.09a
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• pp.499-500
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• 2003

To investigate the potency of some natural extracts as skin whitening agents, in this study, 25 natural plants were prepared from natural sources including medicinal plants, such as Angelica dahurica using methylene dichloride, ethyl acetate, n-butyl alcohol, and water as the extraction and/or the partitioning solvents. These natural extracts were subsequently subjected to in-vitro DOPA auto-oxidation test in the media containing human or mushroom tyrosinase as the oxidation promoting enzymes. Most of the extracts showed relatively higher enzyme inhibition(omitted)

• Journal of Ginseng Research
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• v.16 no.3
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• pp.228-234
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• 1992

There has been general tendency to explain the traditional ginseng efficacy through the pharmacological and biochemical activities of ginsenosides. However, when we analyze the pharmacological and biological data on ginseng reported yet, we can easily arrive at the conclsion that most of the data on pharmacological and biological activities must have been obtained using impure ginsenoside samples, which should contain some non-saponin constituents as impurities. Based on the above back-ground, the non-saponin constituents of ginseng were studied in our laboratory. Phenolic substances including Maltol, Vanillic Acid, Salicylic Acid, Ferrulic Acid and Caffeic acid and impure ginsenoside samples were found to show strong antioxidant and anti-fatigue activities, while pure ginsenosides were devoid of the activities. Maltol, one of antioxidant components In Korean red ginseng drew a special interest due to its very low pro-oxidant activity. The antioxidant activity of ginseng may be considered as scientific basis for the antiageing activity which was described in traditional medicinal material book as "long-term medication of ginseng will improve bio-efficiency and extend life-span" The lignin components, another non-saponin consitutents, isolated from ginseng extract In our laboratory may eplain the hepato-protective activity of ginseng which has been repeatedly rtaimed as one of the efficacies of ginsenosides. The P-carboline alkaloids isolated in our laboratory as one of the non-saponin constituents of ginseng may play some pharmacological activities which should also be investigated. Present paper will include chemistry and biochemical aspects of the non-saponin constituents of ginseng with special interests for the explanation of traditional ginseng efficacy on modern scientific basis.fic basis.

• Korean Journal of Pharmacognosy
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• v.1 no.2
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• pp.1-10
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• 1970

The cyclization of geranylgeranyl pyrophosphate followed by ionization, proton elimination or cation center migration produces dicyclic, tricyclic and tetracyclic diterpenoids. The role of some of diterpenoids in animals is well known but their precise functions in plants remain to be explained.