Chemical Constituents of Euonymus alatus (Thunb.) Sieb. and Their PTP1B and α-Glucosidase Inhibitory Activities.

Phytochemical study on the corks of Euonymus alatus resulted in the isolation of a novel 3-hydroxycoumarinflavanol (23), along with ten triterpenoids (1-10), ten phenolic derivatives (11-20), and two flavonoid glycosides (21 and 22). Their structures were determined by extensive 1D and 2D-nuclear magnetic resonance spectroscopic and mass spectrometry data analysis. Furthermore, their inhibitory effects against the protein tyrosine phosphatases 1B (PTP1B) and α-glucosidase enzyme activity were evaluated. Compounds 6, 7, 9, 15, 19, and 23 were non-competitive inhibitors, exhibiting most potency with IC50 values ranging from 5.6 ± 0.9 to 18.4 ± 0.3 µm, against PTP1B. Compound 3 (competitive), compounds 5 and 15 (mixed-competitive) displayed potent inhibition with IC50 values of 15.1 ± 0.7, 23.6 ± 0.6 and 14.8 ± 0.9 µm, respectively. Moreover, compounds 15, 20, and 23 exhibited potent inhibition on α-glucosidase with IC50 values of 10.5 ± 0.8, 9.5 ± 0.6, and 9.1 ± 0.5 µm, respectively. Thus, these active ingredients may have value as new lead compounds for the development of new antidiabetic agents.

Simultaneous quantitation and validation of method for the quality evaluation of Eucommiae cortex by HPLC/UV.

A new HPLC/UV method has been developed for the simultaneous quantitative determination of four major components in Eucommiae cortex, namely geniposidic acid (1), geniposide (2), pinoresinol di-O-ß-D-glucopyranoside (3), and liriodendrin (4). Simultaneous separations of these four components were achieved on a J'sphere ODS C(18) column (250 × 4.6 mm, 4 µm). The elution was done using water with 0.1% phosphoric acid (A) and acetonitrile with 0.1% phosphoric acid (B) in a two-step elution of the mobile phase at a flow rate of 1.0 mL/min and a wavelength of 230 nm. The method was validated for linearity, recovery, precision, accuracy, stability and robustness. All calibration curves showed good linear regression (r(2) > 0.999) within the test ranges. This method showed good recovery and reproducibility for the quantification of these four components in 85 species of Eucommiae cortex. The intra-day and inter-day precisions were lower than 0.53% (as a relative standard deviation, RSD) and accuracies between 93.00 and 106.28% for all standards. The results indicate that the established HPLC/UV method is suitable for quantitation and quality evaluation of Eucommiae cortex.

Quantitative analysis of marker compounds in Angelica gigas, Angelica sinensis, and Angelica acutiloba by HPLC/DAD.

Although Danggui is the root of Angelica gigas NAKAI in the Korean Pharmacopoeia, it is determined that Danggui is also the root of Angelica sinensis (OLIV.) DIELS in China and Hong Kong, as well as the root of Angelica acutiloba KITAGAWA in Japan. Accordingly, we tried to develop an identification method using the main compounds in A. gigas, A. sinensis, and A. acutiloba through HPLC/diode-array detector (DAD). This method was fully validated for linearity, accuracy, precision, recovery, and robustness. Multivariate analysis was also implemented after pattern analysis and monitoring. As a result, each compound pattern of A. gigas, A. sinensis, and A. acutiloba was identified, making it possible to distinguish them from each other.

Quantitative determination and pattern recognition analyses of bioactive marker compounds from Dipsaci Radix by HPLC.

In this study, quantitative and pattern recognition analyses were developed using HPLC/UV for the quality evaluation of Dipsaci Radix. For quantitative analysis, five major bioactive compounds were assessed. The separation conditions employed for HPLC/UV were optimized using ODS C18 column (250 × 4.6 mm, 5 µm) with a gradient of acetonitrile and water as the mobile phase at a flow rate of 1.0 mL/min and a detection wavelength of 212 nm. These methods were fully validated with respect to linearity, accuracy, precision, recovery, and robustness. The HPLC/UV method was applied successfully to the quantification of five major compounds in the extract of Dipsaci Radix. The HPLC analytical method for pattern recognition analysis was validated by repeated analysis of 17 Dipsaci Radix and four Phlomidis Radix samples. The results indicate that the established HPLC/UV method is suitable for quantitative analysis.

Induction of microtubule-damage, mitotic arrest, Bcl-2 phosphorylation, Bak activation, and mitochondria-dependent caspase cascade is involved in human Jurkat T-cell apoptosis by aruncin B from Aruncus dioicus var. kamtschaticus.

Exposure of human Jurkat T cells to aruncin B, purified from Aruncus dioicus, caused apoptosis along with microtubule damage, G(2)/M-arrest, Bcl-2 phosphorylation, Bak activation, mitochondrial membrane potential (Δψm) loss, cytochrome c release, activation of multiple caspases, and PARP degradation. Analyses by employing Bcl-2 overexpression and selective caspase inhibitors revealed that G(2)/M-arrest and Bcl-2 phosphorylation occurred prior to mitochondria-dependent activation of caspase-9, -3, and -8. The IC(50) values for human resting T cells, activated T cells, and Jurkat T cells were >60µg/ml, 49µg/ml, and 22µg/ml, respectively. These results demonstrate the apoptogenic activity of a novel microtubule-damaging agent aruncin B.

Constituents with DNA topoisomerases I and II inhibitory activity and cytotoxicity from the roots of Rubia cordifolia.

Activity-directed isolation of the ethyl acetate fraction from the roots of Rubia cordifolia resulted in the identification of a new anthraquinone, 1,3,6-trihydroxy-2-hydroxymethyl-9,10-anthraquinone-3- O- α- L-rhamnopyranosyl-(1 → 2)- ß-D-(6'-O-acetyl)-glucopyranoside (1), two new dihydronaphtoquinones, 1,4-dihydroxy-2-carbomethoxy-3-prenylnaphthalene-1-O- ß-D-glucopyranoside (2) and mollugin-1-O- ß- D-glucopyranoside (3), and a new monoterpenoid, 3 R,3a S,4 R,6a R-3,4,6-tris(hydroxymethyl)-3,3a,4,6a-tetrahydro-2 H-cyclopenta[ B]furan-2-one (4), together with nine known compounds (5-13). The structures of these compounds were elucidated on the basis of spectroscopic evidence. In addition, their DNA topoisomerases I and II inhibitory activity and cytotoxicity were measured.

A new cytotoxic coumarin, 7-[(E)-3',7'-dimethyl-6'-oxo-2',7'-octadienyl] oxy coumarin, from the leaves of Zanthoxylum schinifolium.

A new coumarin, 7-[(E)-3',7'-dimethyl-6'-oxo-2',7'-octadienyl]oxy coumarin (1), together with three known compounds, schinilenol (2), schinindiol (3) and 7-[(E)-7'-hydroxy-3',7'-dimethylocta-2',5'-dienyloxy]-coumarin (4) were isolated from the methylene chloride fraction of Z. schinifolium by normal and reverse phase column chromatographies. Their structures were determined on the basis of physical and spectroscopic evidences. Compound 1 (IC(50) 8.10 µM) showed potent cytotoxicity compared to auraptene (IC(50) 55.36 µM) against Jurkat T cells. The other isolated compounds 2 and 4 exhibited weak cytotoxicities.

Monoterpenoids from the aerial parts of Aruncus dioicus var. kamtschaticus and their antioxidant and cytotoxic activities.

The aerial parts of Aruncus dioicus var. kamtschaticus afforded five new monoterpenoids (1-5): 4-(erythro-6,7-dihydroxy-9-methylpent-8-enyl)furan-2(5H)-one (1, aruncin A), 2-(8-ethoxy-8-methylpropylidene)-5-hydroxy-3,6-dihydro-2H-pyran-4-carboxylic acid (2, aruncin B), 4-(hydroxymethyl)-6-(8-methylprop-7-enyl)-5,6-dihydro-2H-pyran-2-one-11-O-ß-D-glucopyranoside (3, aruncide A), (3S,4S,5R,10R)-3-(10-ethoxy-11-hydroxyethyl)-4-(5-hydroxy-7-methylbut-6-enyl)oxetan-2-one-11-O-ß-D-glucopyranoside (4, aruncide B), and (3S,4S,5R,7R)-5-(9-methylprop-8-enyl)-1,6-dioxabicyclo[3,2,0]heptan-2-one-7-(hydroxymethyl)-12-O-ß-D-glucopyranoside (5, aruncide C). Compound 2 showed potent cytotoxicity against Jurkat T cells with an IC(50) value of 17.15 µg/mL. In addition, compounds 7 and 10 exhibited moderate antioxidant activity with IC(50) values of 46.3 and 11.7 µM, respectively.