• Natural Product Sciences
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• v.19 no.1
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• pp.8-14
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• 2013

The inhibitory effect and the structure-activity relationships of luteolin and its related derivatives isolated from Taraxacum mongolicum against MAO activities were investigated. The activity-guided isolation of extract from Taraxacum mongolicum led to the isolation of three flavonoids, luteolin, diosmetin, and luteolin-7-glucoside, a polyphenol, chlorogenic acid, a tyrosine and a uridine. The inhibitory activities of luteolin and its related derivatives against MAOs activities are dependent on their molecular structures. The presence of the phenolic hydroxy group at para-position is the active site for MAO-A inhibition as well as of MAO-B. The methoxy group has no potential on MAO-A inhibition. An additional phenolic hydroxy group at the ortho-position alleviates about 4-fold MAO-A inhibitory activity of phenolic hydroxy group at para-position. A carboxylic group seems to be critical for DBH inhibition and has no effects on MAO.

• Natural Product Sciences
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• v.2 no.1
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• pp.43-47
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• 1996

Macrophages play an important role in host defense against tumors by killing tumor cells. Our work is directed toward studying the effect of the extracts of Salvia plebeia on induction of antitumor activity in macrophages, since it has been usezd as a folk-medicine for the treatment of hepatitis and tumors. The ability of macrophage treated with the plant extracts to inhibit the growth of tumor cells was assessed. The Extracts of the plant induced antitumor activity and could enhance the tumoricidal activity of macrophages when used in combination with $IFN-{\gamma}$. These results suggest that Salvia plebeia extract contain immunomodulatory factors responsible for the induction of the antitumor activity.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.1
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• pp.230-233
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• 2005

The cytotoxic activity of $13(E)-labd-13-ene-8{\alpha}$, 15-diol (1), isolated from the ethanol extract of Brachyglottis monroi, was evaluated against human oral epithelioid carcinoma cells(KB).

• Natural Product Sciences
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• v.2 no.2
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• pp.96-101
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• 1996

A new natural product, 3,4,8-trihydroxybenzopyranopyran-6,9-dione was isolated from the aqueous ethanolic gall extract of Tamarix aphylla (Tamaricaceae) along with the known phenolics, monodecarboxyellagic acid and brevifolin carboxylic acid as well. The structures have been established by ESI-MS, $^1H$ and $^{13}C$ NMR spectral analysis. Antiinflammatory, antipyretic and ulcerogenic activities determination for both plant (Tamarix aphylla and Phragmites australis) were carried out on aq. ethanolic of extracts.

• Korean Journal of Pharmacognosy
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• v.25 no.3
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• pp.214-220
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• 1994

From the Viticis Fructus n-hydrocarbons, ${\beta}-sitosterol$ $3-O-{\beta}-_D-glucoside$ and hesperidin along with the known polyoxygenated flavonoids such as vitexicarpin, artemetin and luteolin, and vanillic acid were isolated and identified by means of spectroscopic methods. HPLC analysis of the flavonoid components from the MeOH extract was established. Phytochemical analyses of the domestic plant sample and the imported ones were conducted and the flavonoid compositions of the domestic samples were greatly different from those of the imported ones.

• Natural Product Sciences
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• v.7 no.2
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• pp.49-52
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• 2001

Anti-lipid peroxidative activity and phytochemical study on the leaves of Glycine max Meer. were investigated. The methanol extract of the leaves of G. max reduced the level of lipid peroxides induced by bromobenzene in vitro. From the leaves of this plant, apigenin, genistein $7-O-{\beta}-D-glucopyranoside$, kaempferol $3-O-{\beta}-D-glucopyranoside$, and kaempferol 3-O-sophoroside were isolated and characterized by spectral data.

• Natural Product Sciences
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• v.19 no.3
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• pp.231-235
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• 2013

Activity-guided isolation to search for antifibrotic compounds from natural products using HSC-T6 cells afforded nine flavonoids or phenolics, luteolin (1), 3'-O-methylorobol (2), acactin 7-rutinoside (3), sedelolactone (4), 4-methoxyphenol (5), 4-hydroxyaldehyde (6), 4-hydoxyaldehyde (7), 4-hydroxy-3-methoxybenzoic acid (8), and ferulic acid (9) from the methanolic extract of aerial parts of Eclipta prostrata L.. Among the isolated compounds, luteolin (1) significantly inhibited the proliferation of HSCs in dose- and time-dependent manners. Antifibrotic activity of E. prostrata and its phenolic compounds might provide potential therapeutical choice in the treatment of hepatic fibrosis.

• Archives of Pharmacal Research
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• v.27 no.10
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• pp.1020-1022
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• 2004

A new ceramide alomacrorrhiza A was isolated from the ethanolic extract of the plant Alocasia macrorrhiza (L.) Schott. Its chemical structure was elucidated as (2S,3S,4R)-2N-[(2'R)-2'- hydroxy-hexacosanoyl]-tetradecane-1,3,4-triol based on extensive 1D, 2D NMR, EI-MS, FABMS, HR-FAB-MS spectroscopic data and chemical degradation studies.

• Nuclear Engineering and Technology
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• v.49 no.1
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• pp.234-244
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• 2017

Natural frequencies of immersed square sections decrease due to a contribution of added mass to the movement of square sections. In this study, natural frequencies of square sections are obtained as a function of gap size between the square section and a rigid square wall using the finite element method. Additionally, they are used to extract the added mass effect on translational and rotation motions. Published information and studies on the translational and torsional vibration of square beams are also examined for practical use. D coupling of a square section is also investigated for multiple square sections. The suggested added mass estimation can be applicable to the spent fuel storage design of a pressurized light water modulated nuclear power plant.

• Natural Product Sciences
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• v.8 no.4
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• pp.129-132
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• 2002

The MeOH extract of the twig of Morus alba L. (Moraceae) inhibited strong lipid peroxidation activity. In order to find out active principle from the plant, acivity-guided fractionation was performed and five antioxidant compounds were isolated. Their chemical structures were identified as 6-geranylapigenin (1), 6-geranylnorartocarpetin (2), resveratrol (3), oxyresveratrol (4) and quercetin (5) by physicochemical and spectrometric methods. Compounds 1-5 significantly inhibited lipid peroxidation in rat brain homogenate $(IC_{50}\;values\;of\;3.37,\;3.74,\;0.23,\;0.29\;and\;0.06\; {\mu}M,\;respectively)$.