Aphrodisiac Principles and other Constituents from the Roots of Panax quinguefolium and Panax ginseng.

Bioassay-guided fractionation of P. quinquefolium and P. ginseng root extracts afforded six compounds. Among these, two bioactive compounds ginsenoside Re (1) and (20S)-ginsenoside Rg2 (5) exhibiting significant relaxation in rabbit corpus cavernosum with EC50 values of 95.1 and 114.7 µM, respectively. In addition, the phytochemical composition of the water extract of the roots of P. quinquefolium was investigated, and thirty-one compounds were characterized, including four undescribed compounds panajaponol B (18) and panaxjapynes D-F (21-23). Moreover, the spectral characteristics and biosynthetic pathway of Panax triterpene saponins were discussed according to our results and some previous reports.

Isolation and synthesis of melodamide A, a new anti-inflammatory phenolic amide from the leaves of Melodorum fruticosum.

Together with twelve known compounds (2-13), melodamide A (1), a new phenolic amide possessing p-quinol moiety, was purified and characterized from the methanolic extracts of the leaves of Melodorum fruticosum. The structure of melodamide A (1) was established with a combination of 2D NMR experiments, HR-ESI-MS and X-ray analyses. The other known compounds were identified by comparison of their spectroscopic and physical data with those reported in the literature. Moreover, some isolated compounds were examined for their inhibitory activity towards superoxide anion generation and elastase release in human neutrophils. Among the tested compounds, 1, 3, and 5 exhibited strong inhibition of superoxide anion generation with IC50 values ranging from 5.25 to 8.65 µM. Furthermore, synthesis and biological evaluation of melodamide A (1) and its analogs (14a-p) were described.

Drimane-type sesquiterpenes with a dioxabicyclooctane skeleton from the fruiting bodies of Nigrofomes melanoporus and their cytotoxicity.

Two new drimane-type compounds, nigrofomins A ( 1) and B ( 2), possessing a rare dioxabicyclooctane moiety, were purified from the fruiting bodies of Nigrofomes melanoporus. Their structures were determined using 1D-, 2D-NMR and HR-ESI-MS spectroscopic analyses. In addition, 1 was established by X-ray crystallographic studies. Both nigrofomins A ( 1) and B ( 2) exhibited cytotoxicity on acute T-cell leukemia (Jurkat), human nasopharyngeal carcinoma (NPC-TW01), and lung cancer (NCI-H661) cells with IC (50) values in the range of 99.44-246.32 µM. Furthermore, the effects of 1 and 2 on cell-cycle progression of Jurkat cells displayed a concentration-dependent accumulation in the G (0)/G (1) phase.

Biologically active constituents from the fruiting body of Taiwanofungus camphoratus.

Five new benzenoids, benzocamphorins A-E (1-5), and 10 recently isolated triterpenoids, camphoratins A-J (16-25), together with 23 known compounds including seven benzenoids (6-12), three lignans (13-15), and 13 triterpenoids (26-38) were isolated from the fruiting body of Taiwanofungus camphoratus. Their structures were established by spectroscopic analysis. Selected compounds were examined for cytotoxic and anti-inflammatory activities. Compounds 9 and 21 showed moderate cytotoxicity against MCF-7 and Hep2 cell lines with ED(50) values of 3.4 and 3.0µg/mL, respectively. Compounds 21, 25, 26, 29-31, 33, and 36 demonstrated potent anti-inflammatory activity by inhibiting lipopolysaccharide (LPS)-induced nitric oxide (NO) production with IC(50) values of 2.5, 1.6, 3.6, 0.6, 4.1, 4.2, 2.5, and 1.5µM, respectively, which were better than those of the nonspecific nitric oxide synthase (NOS) inhibitor N-nitro-l-arginine methyl ester (l-NAME) (IC(50): 25.8µM). These results may substantiate the use of T. camphoratus in traditional Chinese medicine (TCM) for the treatment of inflammation and cancer-related diseases. The newly discovered compounds deserve further development as anti-inflammatory candidates.

Bioactive constituents from the roots of Panax japonicus var. major and development of a LC-MS/MS method for distinguishing between natural and artifactual compounds.

Two new saponins, panajaponol (1) and pseudoginsenoside RT1 butyl ester (2), together with 35 known compounds (3-37), were isolated from the roots of Panax japonicus var. major. The structures of 1 and 2 were elucidated on the basis of spectroscopic analysis and chemical methods. Furthermore, a LC-MS/MS method was developed for confirming 2, 3, and 8 as natural compounds containing a butyl ester group. This method should be useful for distinguishing between minor natural and artifactual compounds in Panax species. Moreover, compounds 3, 6, 8, 9, 11, 13, and 15 exhibited strong inhibition of superoxide anion generation and elastase release by human neutrophils in response to formyl-l-methionyl-l-leucyl-l-phenylalanine/cytochalasin B (fMLP/CB), with IC(50) values ranging from 0.78 to 43.6 µM. In addition, 1 showed greater than 2- to 3-fold selective cytotoxic activity against KB and DU145 cancer cell lines.

Preparation of a series of novel bichalcones linked with a 1,4-dimethylenepiperazine moiety and examination of their cytotoxicity.

The chalcone basic skeleton is a unique template which is associated with widespread biological activities. In the present study, a series of novel bichalcones linked with a 1,4-dimethylenepiperazine moiety was prepared through Mannich reaction and Clasien-Schmidt condensation. The synthetic analogs 2-16 were subjected into the cytotoxicity examinations using a panel of 25 human tumor cell lines. Among the tested compounds, 3 and 4 which possessed the 3-pyridyl and phenyl groups as the substructure, respectively, displayed significant cytotoxicity against all the tumor cell lines. The results suggested that these bichalcones were potential to be the anticancer lead drugs.

Chemical constituents and biological studies of the leaves of Grevillea robusta.

Three new compounds: Graviquinone (1), cis-3-hydroxy-5-pentadecylcyclohexanone (2), and methyl 5-ethoxy-2-hydroxycinnamate (3), and thirty-eight known compounds were isolated and identified from the leaves of Grevillea robusta. The structures of these compounds were determined by spectroscopic and chemical transformation methods. Graviquinone (1) showed the strongest cytotoxicity against MCF-7, NCI-H460, and SF-268 cell lines. Methyl 2,5-dihydroxycinnamate (4), graviphane (13), and dehydrograviphane (14) exhibited very potent DPPH scavenging activity compared with α-tocopherol. Methyl 2,5-dihydroxycinnamate (4) and bis-norstriatol (17) demonstrated strong inhibition of L-DOPA oxidation by mushroom tyrosinase compared with kojic acid.

ß-carboline alkaloids from Stellaria dichotoma var. lanceolata and their anti-inflammatory activity.

The present investigation on the chemical constituents of the roots of Stellaria dichotoma var. lanceolata has resulted in the isolation of 21 ß-carboline alkaloids, including 13 new compounds, dichotomides III-XIV (1-12) and dichotomine E (13), and eight known compounds. The structures of the new compounds were established on the basis of spectroscopic data analysis. Among these isolated alkaloids, five compounds were examined for their anti-inflammatory potential for the inhibition of NO production in LPS-treated RAW 264.7 cells. All compounds tested exhibited significant inhibition of NO production, with IC(50) values in the range of 11.3 to 19.3 µM.

Camphoratins A-J, potent cytotoxic and anti-inflammatory triterpenoids from the fruiting body of Taiwanofungus camphoratus.

Ten new triterpenoids, camphoratins A-J (1-10), along with 12 known compounds were isolated from the fruiting body of Taiwanofungus camphoratus. Their structures were established by spectroscopic analysis and chemical methods. Compound 10 is the first example of a naturally occurring ergosteroid with an unusual cis-C/D ring junction. Compounds 2-6 and 11 showed moderate to potent cytotoxicity, with EC(50) values ranging from 0.3 to 3 µM against KB and KB-VIN human cancer cell lines. Compounds 6, 10, 11, 14-16, 18, and 21 exhibited anti-inflammatory NO-production inhibition activity with IC(50) values of less than 5 µM, and were more potent than the nonspecific NOS inhibitor N(ω)-nitro-L-arginine methyl ester.

A feasible and practical 1H NMR analytical method for the quality control and quantification of bioactive principles in Lycii Fructus.

Lycii Fructus, a solanaceous drug, is widely used as functional foods and in Traditional Chinese Medicine. Samples collected from different regions of China have been found to be not identical in chemical compositions which might affect the biological activities. Although many chromatographic and spectrometric methods have been reported to determine the concentration of betaine and other bioactive amino acids, disturbance resulted from other polar substances with low UV-absorbance and expensive mass facilities reduced the applicability of these techniques. In the present study, the strong cation exchange solid phase extraction procedure incorporated with 1H NMR was successfully developed as a rapid and reliable method that can simultaneously determine betaine, citric acid, threonine, alanine, and proline in various Lycii Fructus. In addition, ERETIC 2 method based on PULCON principle was also applied and compared with conventional method. This feasible and practical method offers a very powerful tool for the quality control of commercial Lycii Fructus from different sources.

Mechanistic Study of Tetrahydrofuran- acetogenins In Triggering Endoplasmic Reticulum Stress Response-apotoposis in Human Nasopharyngeal Carcinoma.

For past three decades, numerous studies have elucidated the antiproliferative effects of acetogenins in hopes of developing a new class of clinical anticancer agents. However, clear and definitive action mechanisms of acetogenins were less clarified. In the present study, three tetrahydrofuran (THF)-containing acetogenins were found to have potent and selective antiproliferative activity against human nasopharyngeal carcinoma (NPC) cell lines and their methotrexate-resistant counterparts. The THF-containing acetogenins induced G2/M phase arrest, mitochondrial damage and apoptosis, and increased cytosolic and mitochondrial Ca2+ in NPCs. Microarray analysis of NPC-TW01 cells treated with squamostatin A, a non-adjacent bis-THF acetogenin, demonstrated an increased endoplasmic reticulum (ER)-stress response (ESR). Enhanced ESR in squamostatin A-treated cells was confirmed by real-time PCR, Western blot and shRNA gene knockdown experiments. Although our results showed that squamostatin A-induced ESR was independent of extracellular Ca2+, the presence of extracellular Ca2+ enhanced the antiproliferative effect of acetogenins. In vivo analyses demonstrated that squamostatin A showed good pharmacokinetic properties and significantly retarded NPC tumor growth in the xenograft mouse model. Conclusively, our work demonstrates that acetogenins are effective and selective inducers of the ESR that can block NPC proliferation, and illustrate a previously unappreciated antitumor mechanism of acetogenins that is effective against nasopharyngeal malignancies.

Ajugalide-B (ATMA) is an anoikis-inducing agent from Ajuga taiwanensis with antiproliferative activity against tumor cells in vitro.

Ajuga taiwanensis is widely used for the treatment of hepatitis and hepatoma in Taiwanese folk medicine. However, its bioactive components and mechanism of action are unclear. Herein, ajugalide-B (ATMA), a neoclerodane diterpenoid isolated from Ajuga taiwanensis, is reported to exhibit high anti-proliferative activity against tumor cell lines from various tissues. These results demonstrate that ATMA disrupts the focal adhesion complex by decreasing phosphorylation of paxillin and focal adhesion kinase (FAK). As a result, anoikis, a specific type of apoptosis caused by detachment of cells, is triggered by activation of caspase-8 in A549 cells. Furthermore, ATMA also blocks anchorage-independent growth and cell migration and, therefore, ATMA may serve as a lead compound for the developing of anti-cancer therapeuties with anoikis-inducing properties.

Bioactive constituents of Clausena lansium and a method for discrimination of aldose enantiomers.

Glycosides, clausenosides A and B, and carbazole alkaloids, clausenaline A, claulamine A, and claulamine B, together with 50 known compounds, were isolated from the stems of Clausena lansium. Their structures were determined by means of spectroscopic methods, including that of CD and 1D/2D NMR analysis. Claulamine A has a 1-oxygenated carbazole skeleton with a rare 2,3-lactone ring, and claulamine B represents an hitherto unknown acetal carbazole alkaloid. Thirty-one of the isolated known compounds were evaluated in various assays for anti-inflammatory activity. Among them, imperatorin, isoheraclenin, and osthol exhibited selective and potent inhibition of formyl-l-methionyl-l-leucyl-l-phenylalanine/cytochalasin B (fMLP/CB)-induced superoxide anion generation, and lansiumarin C also decreased nitric oxide (NO) and tumor necrosis factor-α (TNF-α) production in lipopolysaccharide (LPS)-induced macrophages. In addition, a modified HPLC method of pre-column derivatization was developed that is more practical for simultaneous analysis of aldose enantiomers as compared to the literature method. The absolute configurations of the sugar moieties in clausenosides A and B were determined with this modified method.

Isolation of substances with antiproliferative and apoptosis-inducing activities against leukemia cells from the leaves of Zanthoxylum ailanthoides Sieb. & Zucc.

Extraction of the leaves of Zanthoxylum ailanthoides Sieb. & Zucc. affords extracts and four isolated compounds which exhibit activities against leukemia cells. The chloroform-soluble fraction (ZAC) of the crude extract of this plant showed cytotoxic activity against human promyelocytic leukemia (HL-60) and myelomonocytic leukemia (WEHI-3) cells with IC(50) values of 73.06 and 42.22 µg/mL, respectively. The active ZAC was further separated to yield pheophorbide-a methyl ester (1), pheophorbide-b methyl ester (2), 13(2)-hydroxyl (13(2)-S) pheophorbide-a methyl ester (3) and 13(2)-hydroxyl (13(2)-R) pheophorbide-b methyl ester (4) whose structures were confirmed by spectroscopic methods. Compounds 2-4 showed cytotoxic activities against both leukemia cells with IC(50) value in the range of 46.76-79.43 nM, whereas compound 1 exhibited only weak cytotoxic activity. The extracts and compounds 1-4 also induced apoptosis and DNA damage in leukemia cells after treatment. The results suggested that the Z. ailanthoides is biologically active against leukemia cells.

Anti-inflammatory, anticholinesterase and antioxidative constituents from the roots and the leaves of Salvia nipponica Miq. var. formosana.

Reactive oxygen species and granule proteases produced by neutrophils contribute to the pathogenesis of inflammatory diseases. The extracts of the roots and the leaves of Salvia nipponica var. formosana were showed potent inhibitory effects on superoxide anion production in fMLP/CB-activated human neutrophils as well as other anti-inflammatory effects, and led to the isolation of 25 compounds. Among them, compounds 8, 12, 13, 14, 15, 17 and 20 were exhibited more potent inhibitory effect on superoxide anion generation and elastase release by human neutrophils in response to fMLP/CB. Moreover, those isolated compounds also showed significant anticholinesterase and antioxidative activities. To the best of our knowledge, this is the first report of phytochemical and biological activity study on S. nipponica var. formosana.

Potent alpha-glucosidase inhibitors from the roots of Panax japonicus C. A. Meyer var. major.

Bioassay-guided fractionation of the CHCl(3) soluble portion of the roots of Panax japonicus C. A. Meyer var. major afforded an active fraction with inhibitory activity against baker's yeast alpha-glucosidase with an IC(50) value 1.02 mg/mL. Furthermore, the active fraction isolated contained three previously unreported polyacetylenes, designated panaxjapynes A-C, together with 11 other compounds, including four polyacetylenes, five phenolic compounds, a sesquiterpenoid, and a sterol glucoside. The structures of the compounds were elucidated by spectroscopic and chemical methods. Compared with the control acarbose (IC(50) 677.97 microM), six compounds were shown to be more potent alpha-glucosidase inhibitors with IC(50) values in the range 22.21-217.68 microM.

Anthraquinones from Ophiorrhiza hayatana OHWI.

Three new naturally occurring anthraquinones, ophiohayatone-A (1), -B (2), and -C (3), together with four known anthraquinones, were isolated from Ophiorrhiza hayatana OHWI (Rubiaceae). Structures of these new compounds were established by spectral methods.