Phytochemical constituents from the florets of tiger grass Thysanolaena latifolia from Nepal.

Phytochemical investigation on the florets of Thysanolaena latifolia leads to the isolation of a new compound 6″-O-acetylorientin-2″-O-α-L-rhamnopyranoside (1), named amrisoside and other 34 known compounds. The chemical structures of the compounds were determined from the interpretation of spectroscopic data including NMR, MS, and IR. This is the first report of phytochemical constituents from the monotypic genus Thysanolaena.

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.

Neolignans from the fruits of Magnolia obovata and their inhibition effect on NO production in LPS-induced RAW 264.7 cells.

Three new neolignans, named 9-methoxyobovatol (6), magnobovatol (7), and 2-hydroxyobovaaldehyde (9), along with six known ones, magnolol (1), honokiol (2), isomagnolol (3), obovatol (4), obovatal (5), and obovaaldehyde (8), were isolated from the fruits of Magnolia obovata using silica gel and ODS column chromatography. From the results of spectroscopic data including EIMS, IR, 1H- and 13C-NMR, DEPT, and 2D-NMR (gCOSY, gHSQC, gHMBC), the chemical structures were determined. All isolated compounds were evaluated for inhibition activity on nitric oxide production in LPS-induced RAW 264.7 cells, and compounds 1-4, 6, 7, and 9 showed significant activity with IC50 values of 15.8 ± 0.3, 3.3 ± 1.2, 14.1 ± 0.9, 6.2 ± 1.2, 14.8 ± 2.3, 14.2 ± 1.2, and 14.8 ± 3.2 µM, respectively, without any visible toxic effect.

Anti-inflammatory lignans from the fruits of Acanthopanax sessiliflorus.

A new lignan, named acanthosessilin A (1), as well as eight known lignan and lignan glycosides 2-9 were isolated from an ethanolic extract of Acanthopanax sessiliflorus fruits. The chemical structures were determined by spectroscopic methods, including HR-EIMS, 1D NMR (1H, 13C, DEPT), 2D NMR (gCOSY, gHSQC, gHMBC, NOESY), and IR spectroscopy. All isolated compounds were tested for the ability to inhibit LPS-induced nitric oxide production in RAW264.7 macrophages.

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.

Neuroprotective effect of prenylated arylbenzofuran and flavonoids from morus alba fruits on glutamate-induced oxidative injury in HT22 hippocampal cells.

A prenylated arylbenzofuran and six flavonoids were isolated from the fruits of Morus alba L. through silica gel, octadecyl silica gel, and Diaion HP-20 column chromatography. Based on the nuclear magnetic resonance, mass spectrometry, and infrared spectroscopic data, the chemical structures of the compounds were determined to be artoindonesianin O (1), isobavachalcone (2), morachalcone A (3), quercetin (4), astragalin (5), isoquercetin (6), and rutin (7). The isolated compounds were evaluated for protection of HT22-immortalized hippocampal cells against glutamate-induced oxidative stress. Compounds 1 and 3 exhibited protective effects with EC(50) values of 19.7±1.2 and 35.5±2.1 µM, respectively. The major compounds 1-3 and 7 were quantified using liquid chromatography/mass spectrometry analysis and were determined to be 1.88±2.1, 1.90±1.8, 0.78±1.5, and 37.29±2.2 mg/kg, respectively, in the ethanol extract of M. alba L. fruits.