• Korean Journal of Pharmacognosy
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• v.27 no.1
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• pp.20-25
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• 1996

In searching for anticomplementary compounds, three phenylpropanoids were isolated from the roots of Agastache rugosa and identified as rosmarinic acid (RA), rosmarinic acid methyl ester (RAM) and caffeic acid methyl ester (CAM) by NMR analyses. RA and RAM exhibited strong inhibitory activity on both the classical pathway (CP) and the alternative pathway (AP) of the complement system, in vitro, but CAM did far less than RA and RAM. $RAM-M1{\sim}-M5$, the methylated derivatives from the RAM, showed that the inhibitory activity was decreased in inverse proportion to the number of methylated groups and $RAM-M 2{\sim}-M4$, the isomers of two methylated hydroxyl groups, exhibited different inhibition activity.

• Preventive Nutrition and Food Science
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• v.16 no.4
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• pp.328-332
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• 2011

After preparation of acetone, ethanol, methanol, and water extracts (10 g/300 mL) of dried persimmon (Diospyros kaki cv. Fuyu) flower-buds, total phenolic contents (TPC), 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity (RSA), 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) RSA, reducing power (RP), and tyrosinase inhibitory activity of the extracts were evaluated. The methanol extracts produced the highest TPC (113.39 mg gallic acid equivalents/g), DPPH RSA ($IC_{50}=40.25\;{\mu}g/mL$), ABTS RSA ($IC_{50}=58.17\;{\mu}g/mL$) and RP ($IC_{50}=69.43\;{\mu}g/mL$) activities while the water extracts generated the lowest values. The ethanol extract showed the highest tyrosinase inhibitor activity (88.90%) at a concentration of 1 mg/mL. These results indicated that persimmon flower-buds may be a useful source of natural antioxidants.

• Korean Journal of Pharmacognosy
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• v.39 no.3
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• pp.174-178
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• 2008

Melanin is a polymer of phenol which produces hyperpigmentation in the skin. Melanin synthesis is catalyzed by the enzyme tyrosinase. To investigate the whitening activity of the fractions from the ethanol extract of Enteromorpha linza, we studied the inhibitory effect on the tyrosinase activity and melanogenesis in the B16/F1 melanoma cells. The inhibition ratio of tyrosinase activity of ethylacetate fraction from E. linza was as strong as that of kojic acid, a positive control. Also, the melanin production was significantly inhibited by the ethylacetate fraction in a dose dependent manner. The ethylacetate fraction showed the highest activity in the fractions and as strong activity as that of arbutin, a positive control. From these results, we suggest that the E. linza extract might be able to apply to cosmetic and medical fields.

• Archives of Pharmacal Research
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• v.21 no.2
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• pp.106-112
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• 1998

Structure-activity relationship of 20 fluoroquinolones was studied using the susceptible and 4 resistant Escherichia coli which were developed against 4 fluoroquinolones [ciprofloxacin (1), KR-10755 (6), norfloxacin (2), and ofloxacin (3)] in our laboratory. The C-7 and C-8 substituents of fluoroquinolone were important in various functions such as the inhibitory activity on DNA gyrase, permeability, and efflux. Among 20 fluoroquinolones, compounds with a 3-methyl-3,7-diazabicyclo[3.3.0]octan-1(5)-ene-7-yl substituent at the C-7 position or a chlorine substituent at the C-8 position showed a good inhibitory activity on DNA gyrase (especially a mutated DNA gyrase). Compounds with a 3,7-diazabicyclo [3.3.0]octan-1(5)-ene-7-yl substituent at the C-7 position showed good permeability in the susceptible and resistant strains, while compounds with a fluorine substituent at the C-8 position were less eff luxed from cells.

• Natural Product Sciences
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• v.7 no.4
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• pp.114-119
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• 2001

The effect of Rhinacanthus nasutus leaf extract on the growth of dermatophytes had been investigated. In vitro the extract exhibited high activity against various species of dermatophytes (Trichophyton mentagrophytes var. mentagrophytes, T. mentagrophytes var. interdigitale, T. rubrum, Microsporum canis and M. gypseum). The minimal inhibitory concentration (MIC) values of the extract revealed that all the dermatophytes tested had MIC values of 13.6 mg/ml. The extract exhibited fungistatic activity at lower concentrations $({\leq}13.6\;mg/ml\;or\;below\;the\;MIC\;value)$ and fungicidal activity at higher concentrations $({\geq}13.6\;mg/ml$\;or\;above\;the\;MIC\;value)$. The results suggested that the extract acted on the cell wall of the dermatophytes which subsequently leading to the formation of cytopathological and membrane structural degeneration and finally leading to cell lysis and death.

• Korean Journal of Clinical Pharmacy
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• v.8 no.2
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• pp.139-142
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• 1998

The effects of MeOH extracts from 28 herbal medicines on monoamine oxidase (MAO) activity were investigated. MAO was purified from mouse brain and its activity was determined by fluoro-photometry using kynuramine as a substrate. Three MeOH extracts, Coptis japonica, Cinnamomum cassia and Poncirus trifoliate from the herbal medicines showed a strong inhibitory effect with less than $100\;{\mu}g/ml$ in their inhibitory amounts of $50\%$ ($IC_{50}$ values) on MAO activity. Four MeOH extracts including Evodia officinalis exhibited a mild inhibition of MAO activity with $100-200\;{\mu}g/ml$ in their $IC_{50}$ values.

• Bulletin of the Korean Chemical Society
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• v.31 no.4
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• pp.971-975
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• 2010

Eight hydroxylated stilbene derivatives including resveratrol, desoxyrhapontigenin and piceatannol as potential radical scavenger and tyrosinase inhibitor are synthesized using optimized Wittig-Horner reaction for excellent trans-selectivity in good yields. Antioxidant activity was tested against ABTS radical and tyrosinase inhibitory activity was performed with L-tyrosine as the substrate based on previous procedure with some modification. In general, catecholic stilbenes showed stronger activity against ABTS radical and resorcinolic moiety showed stronger tyrosinase inhibitory activity. Synthetic piceatannol which containing both catecholic and resorcinolic moieties showed the strongest activity in both as ABTS radical scavenger and tyrosinase inhibitor with $IC_{50}$ values of 4.1 and $8.6\;{\mu}M$, respectively.

• YAKHAK HOEJI
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• v.45 no.5
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• pp.522-528
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• 2001

Tyrosinase plays an important role in the process of melanin biosynthesis, and it is a biochemical target enzyme for skin-whitening agents and the remedy for disturbances in pigmentation. We have screened 25 natural plant extracts for inhibitory effects against DOPA oxidase activity of tyrosinase. For the inhibitory effect against DOPA oxidase activity of tyrosinase, the recombinant human tyrosinase and the purified mushroom tyrosinase were used. Each of the dried plants extracted with methanol, and then the extracts were subjected to sequential fractionations with methylene chloride, ethyl acetate, n-butanol and water, respective The methylene chloride fractions of Angelica tenuissima, Nardostachys chinensis, Bombyx mop and Saposhnikovia divaricata, and the n-butanol fraction of Bombyx mori notably inhibited the human tyrosinase activity as well as mushroom tyrosinase activity (more than 90% inhibition). This study suggests that the above extracts have a potential as whitening agents as single ingredients or in combination with other of the extracts.

• KSBB Journal
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• v.16 no.2
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• pp.153-157
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• 2001

Alcohol fermentation conditions for the production of plum wine were investigated and further, sensory evaluation and physiological functionalities of the plum wines were also determined and compared with those of plum liquors made by soaking plums in a mixture of commercial soju and 10% sugar for 15, 30, 60 and 120 days. Ethanol was produced maximally when 5% Saccharomyces cerevisiae was added to red plum juices and fermented at 25$^{\circ}C$ for 5 days. Angiotensin-converting enzyme inhibitory activity and fibrinolytic activity of the red plum wine were better than those of the plum liquors. However, the antioxidant activity, the SOD-like activity and the tyrosinase inhibitory activity of the plum liquors were better than those of the red plum wine. On comparing the red plum wine and the various kinds of plum liquors, the red plum wine was shown to be more acceptable by sensory evaluation.

• Mycobiology
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• v.36 no.3
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• pp.148-151
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• 2008

A novel biomass was prepared from Pichia anomala KCCM 11473, which grew well in ginseng-steaming effluent (GSE), and its physiological functionalities and enzyme activities were determined. When the strain was cultured in the GSE (pH 6.0) at 30$^{\circ}C$ for 48 h, 1.6 mg of biomass per ml-cultures was produced. The cell-free extract of the biomass showed high antihypertensive angiotensin I-converting enzyme inhibitory activity of 72.0% and anticholesteromia HMG-CoA reductase inhibitory activity of 46.5%. The cell-free extract also showed 13.0 U per ml and 8.5 U per ml of neutral protease activity and alkaline protease, respectively.