• Archives of Pharmacal Research
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• v.27 no.12
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• pp.1226-1232
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• 2004

Extracts from seventeen seaweeds were determined for tyrosinase inhibitory activity using mushroom tyrosinase with L-tyrosine as a substrate. Only one of them, Ecklonia stolonifera OKAMURA (Laminariaceae) belonging to brown algae, showed high tyrosinase inhibitory activity. Bioassay-guided fractionation of the active ethyl acetate (EtOAc) soluble fraction from the methanolic extract of E. stolonifera, led us to the isolation of phloroglucinol derivatives [phloroglucinol (1), eckstolonol (2), eckol (3), phlorofucofuroeckol A (4), and dieckol (5)]. Compounds 1~5 were found to inhibit the oxidation of L-tyrosine catalyzed by mushroom tyrosinase with $IC_{50}$ values of 92.8, 126, 33.2, 177, and 2.16 ${\mu}g$ /mL, respectively. It was compared with those of kojic acid and arbutin, well-known tyrosinase inhibitors, with $IC_{50}$ values of 6.32 and 112 ${\mu}g$ / mL, respectively. The inhibitory kinetics analyzed from Lineweaver-Burk plots, showed compounds 1 and 2 to be competitive inhibitors with $K_i$ of $2.3{\times}10^{-4}\;and\;3.1{times}10^{-4}$ M, and compounds 3~5 to be noncompetitive inhibitors with $K_i$ of $1.9{\times}10^{-5},\;1.4{\times}10^{-3}\;and\;1.5{\times}10^{-5}$ M, respectively. This work showed that phloroglucinol derivatives, natural compounds found in brown algae, could be involved in the control of pigmentation in plants and other organisms through inhibition of tyrosinase activity using L-tyrosine as a substrate.

• Archives of Pharmacal Research
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• v.27 no.2
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• pp.169-172
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• 2004

Activity-guided fractionation of the EtOAc-soluble extract of the stems of Couepia ulei, using a bioassay based on the induction of quinone reductase (QR) in cultured Hepa 1c1c7 mouse hepatoma cells led to the isolation of two active compounds, a new natural product, erythro-2,3-bis(4-hydroxy-3-methoxyphenyl)-3-ethoxypropan-1-o1 (1), and a known compound, evofolin-B (2), along with five inactive compounds all of known structure, viz., betulinic acid, oleanolic acid, pomolic acid, ($\pm$)-syringaresinol, and ursolic acid. These isolates were identified by analysis of physical and spectral data. Compounds 1 and 2 exhibited QR inducing activity, with observed CD (concentration required to double induction) values of 16.7 and 16.4 $\mu\textrm{M}$, respectively.

• Journal of Korea Foresty Energy
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• v.19 no.1
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• pp.49-60
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• 2000

The traditional Korea medical book already recorded various biological activities of the Korean mistletoes. The objective of this study was examine antifungal activities of MeOH extract from the Korean mistletoe through column chromatography on three fungi, such as Tyromyces palustris Endothia nitschkei and Trichophyton rubrum. No mistletoes had anti-fungal activity against T. palusties. Extracts of V. album var. coloratum showed the highest hyphal growth-inhibitory activity against E. nitschkei and leaf extract of this species had higher activity than twig extract. Further fractionation of most active fraction and following antifungal assay showed that its anti-fungal activity might be caused by synergism if its components. It was suggested that Viscum album var. coloratum shows significantly antifungal activities against E. nitschkei and T. rubrum. Further examination is needed to find out more exact active compounds.

• Korean Journal of Food Science and Technology
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• v.47 no.2
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• pp.170-175
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• 2015

The methanol extract of Asian pear (Pyrus pyrifolia N. cv. Chuhwangbae) fruit peel was purified using solvent fractionation, Sephadex LH-20 column chromatography, and octadecylsilane high performance liquid chromatography. Based on the electrospray ionization mass spectrometry and nuclear magnetic resonance data, the two isolated compounds were identified as quercetin 3-O-${\beta}$-D-glucopyranoside (1) and 3,5,6,7,8,3',4'-heptahydroxyflavan [(-)-dulcisflavan, 2]. Compounds 1 and 2 were isolated and identified for the first time from Asian pears and pears, respectively.

• The Korean Journal of Food And Nutrition
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• v.18 no.4
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• pp.367-372
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• 2005

Antimicrobial effects of the extracts from Castanea crenata leaf were investigated. The antimicrobial effects of methanol extract (8 mg, 20 mg) of 0.2 g and 0.5 g. eq. of Castanea crenata leaf was stronger than that of 0.65 mg of benzoic acid against Gram(+) bacteria such as Staphylococcus aureus, Staphylococcus epidermidis, Micrococcus luteus, Leuconostoc mesenteroides and Bacillus subtilig and Gram(-) bacteria such as Escherichia coli, Salmonella typhimurium, and Pseudomonas aeruginosa. Growth inhibition of various microorganisms was observed in Castanea crenata leaf, therefor the Castanea crenata leaf were solvent fractionated. The ethyl acetate-soluble acidic and phenolic fraction were showed remarkable antimicrobial activity against microorganisms tested. The acidic fraction was purified with silica gel adsorption column chromatography, Sephadex LH-20 column chromatography and HPLC, subsequantly. The antimicrobial active substance isolated from the acid fraction of Castanea crenata leaf was characterized as stigmast-5-en-3-ol($\beta$-sitosterol) by MS and NMR analysis.

• Nutrition Research and Practice
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• v.8 no.5
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• pp.509-515
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• 2014

BACKGROUND/OBJECTIVES: The root of Vitis amurensis Ruprecht, a sort of wild-growing grape, has been used in oriental medicine for treatment of skin ailments; however, its dermatological activity is not sufficiently understood. The aim of this study was to investigate tyrosinase inhibitory and anti-melanogenic activities of V. amurensis Ruprecht root methanol extract (VARM) in B16F10 mouse melanoma cells and to attempt to isolate and identify the active compound issued from VARM. MATERIALS/METHODS: Anti-melanogenic activity of VARM was analyzed in ${\alpha}$-melanocyte stimulating hormone (MSH)-stimulated B16F10 cells through evaluation of antioxidative activity as well as inhibited tyrosinase activity and melanin contents compared with those of kojic acid and arbutin. After anti-melanogenic analysis of VARM, serial fractionation, nuclear magnetic resonance (NMR), and thin layer chromatorgraphy (TLC) were applied for identification of active compounds contained in VARM. RESULTS: VARM significantly inhibited oxidative stress and tyrosinase activity and attenuated ${\alpha}$-MSH-induced melanin production in B16F10 cells. For isolation of active compounds, VARM was fractionated using a series of organic solvents, including dichloromethane ($CH_2Cl_2$), ethyl acetate (EtOAc), and n-butanol (n-BuOH). Among fractions showing anti-melanogenic activity, the CH2Cl2 fraction induced the most potent attenuation of melanogenesis without cytotoxicity and the major compound in the $CH_2Cl_2$ fraction was identified as betulinic acid. Betulinic acid isolated from the $CH_2Cl_2$ fraction of VARM significantly attenuated ${\alpha}$-MSH-induced melanogenesis in a dose dependent manner, which was stronger than that of arbutin used as a positive control. CONCLUSIONS: These results indicate that VARM inhibits oxidative stress, tyrosinase activity, and ${\alpha}$-MSH-induced melanogenesis in B16F10 cells, due primarily to the active compound, betulinic acid, in the $CH_2Cl_2$ fraction.

• Applied Biological Chemistry
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• v.27 no.1
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• pp.40-44
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• 1984

Experiments on the GA production ability by ectomycorrhizal fungus, Pisolithus tinctorius was carried out to investigate specific physiological phenomena of growth increase in host plants by formation of mycorrhizae, The culture extract of P. tinctorius was purified by solvent fractionation, sephadex LH-20 chromatography, silica gel partition chromatography and TLC, successively. GA activities in the purified GA fractions were monitored by micro-drop bioassay using dwarf rice seedlings, 'Tan-ginbozu'. $30{\sim}60%$ EtOAc election fractions of silica gel pardon chromatography and the zone of Rf $0.1{\sim}0.4,\;0.6{\sim}0.8$ of TLC exhibited the GA-like activities. The GA activities were increased with the more treated amount of culture extracts. This activity in 100ml of culture solution was equivalent to 0.1ng of $GA_3$.

• The Journal of Pediatrics of Korean Medicine
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• v.30 no.3
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• pp.1-30
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• 2016

Objectives Previous studies have found out that Forsythiae Fructus (FF) extracts have anti-atopic activities by in vitro experiment. In order to understand more about FF extracts' benefit, we subdivided FF extracts depending on systematic fractionation method by using Methylene chloride (MC), Ethyl acetate (EtOAc), n-BuOH and n-hexane (n-Hx). This study is designed to examine the effect of FF fractions on the PMA- ionomycin-induced activation of RBL-2H3 mast cell lines in vitro and on the DNCB-induced activation of NC/Nga mice in vivo. Methods For this study, we examined IL-4, IL-13 production by ELISA analysis, IL-4, IL-13, IL-31, IL-31RA and TNF-${\alpha}$ mRNA expression by real-time PCR and manifestations of AP-1 and MAPKs transcription factors by western blotting in vitro. Through in vitro experiment, we selected FF n-BuOH fraction that seems the best effective in atopic dermatitis then induced it on NC/Nga mice by DNCB. We measured mice's WBC, eosinophil and neutrophil in heart blood, IL-4, IL-5, IFN-${\gamma}$ in the spleenocyte culture supernatant, the absolute cell numbers of CD4+, CD8+, B220+CD23+, CD3+CD69+ and Gr-1+CD11b+ in the PBMCs, ALN and dorsal skin, IL-5, IL-13, IL-31, IL-31RA in the dorsal skin by real-time PCR and the distribution of immune cells by H&E on dorsal skin and ANL and toluidine blue staining on dorsal skin. Results FF n-BuOH fraction suppressed IL-4, IL-13 production and mRNA expression of IL-4, IL-13, IL-31, IL-31RA and TNF-${\alpha}$. Results from the western blot analysis showed that FF n-BuOH fraction reduced the activation of the mast cell specific transduction factors involved in AP-1 by suppressing JNK and ERK phosphorylation. In the gross, atopic dermatitis induced by DNCB in NC/Nga mice were improved by oral administration of FF n-BuOH fraction. Oral FF n-BuOH fraction also decreased the level of IgE in mice's serum and the level of IL-4 and IL-5 in the spleenocyte culture supernatant, cell numbers of CD8+, B220+CD23+ in the PBMCs, CD4+ in the ALN and CD4+, Gr-1+CD11b+ in the dorsal skin and suppressed mRNA expression of IL-5, IL-13, IL-31, IL-31RA in the dorsal skin. Histological examination showed that infiltration levels of immune cells in atopic dermatitis induced NC/Nga mice were improved by FF n-BuOH fraction. Conclusions FF n-BuOH fraction can reduce pruritus by suppressing IL-31, IL-31RA secretion and modulate molecular mediators and immune cells associated with atopic dermatitis induced in NC/Nga mice which may have played a significant role in recovering atopic dermatitis symptoms.

• Archives of Pharmacal Research
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• v.26 no.8
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• pp.585-590
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• 2003

Activity-guided fractionation of the EtOAc-soluble extract of the whole plants of Sida acuta using a bioassay based on the induction of quinone reductase (OR) in cultured Hepa 1c1c7 mouse hepatoma cells, led to the isolation of ten active compounds of previously known structure, quindolinone (1), cryptolepinone (2), 11-methoxyquindoline (3), N-trans-feruloyltyramine (4), vomifoliol (5), loliolide (6), 4-ketopinoresinol (7), scopoletin (8), evofolin-A (9), and evofolin-B (10), along with five inactive compounds of known structure, ferulic acid, sinapic acid, syringic acid, ($\pm$)-syringaresinol, and vanillic acid. These isolates were identified by physical and spectral data measurement. A new derivative of quindolinone, 5,10-dimethylquindolin-11-one (1a) was synthesized and characterized spectroscopically. Of the active substances, compounds 1-3 and 1a exhibited the most potent QR activity, with observed CD (concentration required to double induction) values ranging from 0.01 to 0.12 $\mu$ g/mL. Six compounds were then evaluated in a mouse mammary organ culture assay, with cryptolepinone (2), N-trans-feruloyltyramine (4), and 5,10-dimethylquindolin-11-one (1a) found to exhibit 83.3, 75.0, and 66.7% inhibition of 7,12-dimethylbenz[a]anthracene-induced preneoplastic lesions, respectively, at a dose of 10 $\mu\textrm{g}$/mL.