Diterpenes from the roots of Oryza sativa L. and their inhibition activity on NO production in LPS-stimulated RAW264.7 macrophages.

Two new pimarane diterpenoids, momilactone D (3) and momilactone E (5), along with three known diterpenoids, momilactone A (1), sandaracopimaradien-3-one (2), and oryzalexin A (4) were isolated from Oryza sativa roots. The chemical structures of the compounds were determined by spectroscopic data analysis. The isolated diterpenoids were evaluated for their ability to inhibit NO production and iNOS mRNA and protein expression in LPS-stimulated RAW264.7 macrophages. Compound 4 showed strong inhibition activity on NO production, and compounds 1 and 4 decreased the expression of iNOS mRNA and protein levels.

Glycosyl glycerides from hydroponic Panax ginseng inhibited NO production in lipopolysaccharide-stimulated RAW264.7 cells.

BACKGROUND: Although the aerial parts of hydroponic Panax ginseng are reported to contain higher contents of total ginsenosides than those of roots, the isolation and identification of active metabolites from the aerial parts of hydroponic P. ginseng have not been carried out so far. METHODS: The aerial parts of hydroponic P. ginseng were applied on repeated silica gel and octadecylsilane columns to yield four glycosyl glycerides (Compounds 1-4), which were identified based on nuclear magnetic resonance, infrared, fast atom bombardment mass spectrometry, and gas chromatography/mass spectrometry data. Compounds 1-4 were evaluated for inhibition activity on NO production in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. RESULTS AND CONCLUSION: The glycosyl glycerides were identified to be (2S)-1-O-7(Z),10(Z),13(Z)-hexadecatrienoyl-3-O-ß-d-galactopyranosyl-sn-glycerol (1), (2S)-1-O-linolenoyl-3-O-ß-d-galactopyranosyl-sn-glycerol (2), (2S)-1-O-linolenoyl-2-O-linolenoyl-3-O-ß-d-galactopyranosyl-sn-glycerol (3), and 2(S)-1-O-linoleoyl-2-O-linoleoyl-3-O-ß-d-galactopyranosyl-sn-glycerol (4). Compounds 1 and 2 showed moderate inhibition activity on NO production in LPS-stimulated RAW264.7 cells [half maximal inhibitory concentration (IC50): 63.8 ± 6.4µM and 59.4 ± 6.8µM, respectively] without cytotoxicity at concentrations < 100µM, whereas Compounds 3 and 4 showed good inhibition effect (IC50: 7.7 ± 0.6µM and 8.0 ± 0.9µM, respectively) without cytotoxicity at concentrations < 20µM. All isolated compounds showed reduced messenger RNA (mRNA) expression of interleukin-1ß (IL-1ß), IL-6, and tumor necrosis factor-α in LPS-induced macrophage cells with strong inhibition of mRNA activity observed for Compounds 3 and 4.

The potential of minor ginsenosides isolated from the leaves of Panax ginseng as inhibitors of melanogenesis.

Three minor ginsenosides, namely, ginsenoside Rh6 (1), vina-ginsenoside R4 (2) and vina-ginsenoside R13 (3), were isolated from the leaves of hydroponic Panax ginseng. The chemical structures were determined based on spectroscopic methods, including fast atom bombardment mass spectroscopy (FAB-MS), 1D-nuclear magnetic resonance (NMR), 2D-NMR, and, infrared (IR) spectroscopy. The melanogenic inhibitory activity of compounds 1, 2 and 3 was 23.9%, 27.8% and 35.2%, respectively, at a concentration of 80 µM. Likewise, the three compounds showed inhibitory activity on body pigmentation on a zebrafish model, which is commonly used as a model for biomedical or cosmetic research. These results from in vitro and in vivo systems suggest that the three aforementioned compounds isolated from Panax ginseng may have potential as new skin whitening compounds.

Inhibition effect of phenyl compounds from the Oryza sativa roots on melanin production in murine B16-F10 melanoma cells.

Five phenyl compounds, vanillin (1), methyl trans-ferulate (2), trans-p-coumaric acid methyl ester (3), N-benzoyltryptamine (4), and N-(trans-cinnamoyl)tryptamine (5), were isolated from the roots of Oryza sativa L. and identified on the basis of spectroscopic data. Compounds 3 and 5 showed strong inhibition effect on melanin production in murine B16-F10 melanoma cells and tyrosinase activity. Also, the quantitative analysis of the compounds was carried out using LC/MS/MS experiment. Compounds 3 and 5 could be used as skin-whitening agents.

Re-evaluation of physicochemical and NMR data of triol ginsenosides Re, Rf, Rg2, and 20-gluco-Rf from Panax ginseng roots.

Ginseng roots were extracted with aqueous methanol, and extracts were suspended in water and extracted successively with ethyl acetate and n-butanol. Column chromatography using the n-butanol fraction yielded four purified triol ginseng saponins: the ginsenosides Re, Rf, Rg2, and 20-gluco-Rf. The physicochemical, spectroscopic, and chromatographic characteristics of the ginsenosides were measured and compared with reports from the literature. For spectroscopic analysis, two-dimensional nuclear magnetic resonance (NMR) methods such as (1)H-(1)H correlation spectroscopy, nuclear Overhauser effect spectroscopy, heteronuclear single quantum correlation, and heteronuclear multiple bond connectivity were employed to identify exact peak assignments. Some peak assignments for previously published (1)H- and (13)C-NMR spectra were found to be inaccurate. This study reports the complete NMR assignment of 20-gluco-Rf for the first time.