Discovery and biological evaluation of a new type of dual inhibitors of indoleamine 2,3-dioxygenase 1 and tryptophan 2,3-dioxygenase from ethnomedicinal plant Dactylicapnos scandens.

The root of Dactylicapnos scandens (D.Don.) Hutch (Papaveraceae), one of the most famous ethno-medicinal plants from the Bai communities in P. R. China, is used to treat various inflammations and tumours. Bioassay-guided phytochemical research on D. scandens followed by semi-synthesis led to a series of undescribed tetrahydroisoquinoline alkaloids with dual inhibitory activities against indoleamine 2,3-dioxygenase 1 (IDO1) and tryptophan 2,3-dioxygenase (TDO). The previously undescribed dark-green alkaloid dactycapnine A exhibited the best dual inhibitor effects among the identified compounds. Structure-activity relationship analysis revealed the importance of the base skeleton with a hyperconjugation system. The performed semi-synthesis further yielded bioactive dimeric and trimeric compounds with hyperconjugated systems. Performed STD NMR experiments disclosed direct interactions between dactycapnine A and IDO1/TDO. Inhibition kinetics indicated dactycapnine A as a mixed-type dual inhibitor. These findings provided a possible explanation for the anticancer properties of the ethno-medicinal plant species D. scandens.

Induction of Callogenesis, Organogenesis, and Embryogenesis in Non-Meristematic Explants of Bleeding Heart and Evaluation of Chemical Diversity of Key Metabolites from Callus.

Lamprocapnos spectabilis (L.) Fukuhara is a perennial plant species valued in the horticultural, cosmetic, and pharmaceutical markets. To date, however, there were no studies on tissue culture systems in this species when adjusted from non-meristematic explants. The aim of this study is to induce callogenesis, organogenesis, and somatic embryogenesis in non-meristematic explants of Lamprocapnos spectabilis 'Alba' cultured in various media and to analyze the chemical diversity of the produced callus. Leaf, petiole, and internode explants were cultured on the modified Murashige and Skoog (MS) medium fortified with various combinations and concentrations of 6-benzyladenine (BA), indole-3-acetic acid (IAA), 1-naphthaleneacetic acid (NAA), 2,4-dichlorphenoxyacetic acid (2,4-D), and picloram (PIC). After 10 weeks of culturing, the morphogenetic response of explants was evaluated and the concentration of chlorophylls, carotenoids, anthocyanins, and polyphenols in callus was analyzed. There was no influence of explant type on the callogenesis efficiency (62.1-65.3%). The highest fresh weight of callus was produced on leaf explants in the presence of 2,4-D or PIC. In contrast, the highest share of dry weight was found in internode-derived calli and cultured on IAA-supplemented medium (up to 30.8%). Only 2.5% of all explants regenerated adventitious shoots, while rhizogenesis was reported in 4.5% of explants. Somatic embryos were produced indirectly by 0% to 100% of explants, depending on the culture medium and explant type. The highest mean number of embryos (11.4 per explant) was found on petioles cultured in the MS medium with 0.5 mg·L-1 BA and 1.0 mg·L-1 PIC. Calli cultured in media with NAA usually contained a higher content of primary and secondary metabolites. There was also a significant impact of explant type on the content of anthocyanins, polyphenols, and carotenoids in callus. Further studies should focus on the elicitation of metabolites production in callus culture systems of the bleeding heart.

Comparative exine development from the post-tetrad stage in the early-divergent lineages of Ranunculales: the genera Euptelea and Pteridophyllum.

Studies of pollen wall development produce a great deal of morphological data that supplies useful information regarding taxonomy and systematics. We present the exine development of Euptelea and Pteridophyllum, two taxa whose pollen wall development has never previously been studied using transmission electron microscopy. Both genera are representatives of the two earliest-diverging families of the order Ranunculales and their pollen data are important for the diagnosis of the ancestral pollen features in eudicots. Our observations show these genera are defined by having microechinate microreticulate exine ornamentation, perforate tectum, columellate morphology of the infratectum and the existence of a foot layer and endexine. The presence of lamellations is detected during the early stages of development in the nexine of both genera, especially in the apertures. Euptelea presents remains of the primexine layer during the whole maturation process, a very thin foot layer, and a laminate exinous oncus in the apertural region formed by ectexine and endexine elements. Pteridophyllum has a thicker tectum than Euptelea, a continuous foot layer and a thicker endexine. In the apertures, the exinous oncus is formed by islets and granules of endexine, in contrast to the Euptelea apertures. The secretory tapetum produces orbicules in both genera, but they have different morphology and electron-density. Comparisons with pollen data from related orders and families confirm the ancestral states for the pollen of eudicots proposed in previous studies: reticulate and echinate surfaces, columellate infractectum and a thin foot layer relative to the thickness of the ectexine. According to our observations, we propose considering the possibility of a polymorphic state for the aperture number in the ancestor of Ranunculales, and suggest the development of orbicules as the ancestral state in this order.

Some contributions to the application of LC-NMR, LC-MS, and LC-CD to the biosynthesis of isoquinoline alkaloids using callus cultures.

Hyphenated spectroscopic techniques in combination with a special extraction and work-up of plant calli cultures of Berberidaceae, Fumariaceae, and Papaveraceae families, e.g., enabled us to get deeper insight into the sequential biochemical conversions of precursors into simple isoquinoline- and protoberberine-alkaloids and their follow-up-products with different skeletons. Some new alkaloids of these types have been found.

Occurrence of sarmentosin and other hydroxynitrile glucosides in Parnassius (papilionidae) butterflies and their food plants.

Sequestration of plant secondary metabolites is a widespread phenomenon among aposematic insects. Sarmentosin is an unsaturated γ-hydroxynitrile glucoside known from plants and some Lepidoptera. It is structurally and biosynthetically closely related to cyanogenic glucosides, which are commonly sequestered from food plants and/or de novo synthesized by lepidopteran species. Sarmentosin was found previously in Parnassius (Papilionidae) butterflies, but it was not known how the occurrence was related to food plants or whether Parnassius species could biosynthesize the compound. Here, we report on the occurrence of sarmentosin and related compounds in four different Parnassius species belonging to two different clades, as well as their known and suspected food plants. There were dramatic differences between the two clades, with P. apollo and P. smintheus from the Apollo group containing high amounts of sarmentosin, and P. clodius and P. mnemosyne from the Mnemosyne group containing low or no detectable amounts. This was reflected in the larval food plants; P. apollo and P. smintheus larvae feed on Sedum species (Crassulaceae), which all contained considerable amounts of sarmentosin, while the known food plants of the two other species, Dicentra and Corydalis (Fumariaceae), had no detectable levels of sarmentosin. All insects and plants containing sarmentosin also contained other biosynthetically related hydroxynitrile glucosides in patterns previously reported for plants, but not for insects. Not all findings could be explained by sequestration alone and we therefore hypothesize that Parnassius species are able to de novo synthesize sarmentosin.

Preparative isolation of alkaloids from Dactylicapnos scandens using pH-zone-refining counter-current chromatography by changing the length of the separation column.

pH-Zone-refining counter-current chromatography was successfully applied for the preparative separation of alkaloids from Dactylicapnos scandens. The two-phase solvent system was composed of petroleum ether-ethyl acetate-methanol-water (3:7:1:9, v/v), where 20 mM of triethylamine (TEA) was added to the upper phase as a retainer and 5 mM of hydrochloric acid (HCl) to the aqueous phase as an eluter. In this experiment, the apparatus with an adjustable length of the separation column was used for the separation of alkaloids from D. scandens and the resolution of the compounds can be remarkably improved by increasing the length of the separation column. As a result, 70 mg protopin, 30 mg (+) corydine, 120 mg (+) isocorydine and 40 mg (+) glaucine were obtained from 1.0 g of the crude extracts and each with 99.2%, 96.5%, 99.3%, 99.5% purity as determined by HPLC. The chemical structures of these compounds were confirmed by positive ESI-MS and (1)H NMR.

Biotransformation of phenolic tetrahydroprotoberberines in plant cell cultures followed by LC-NMR, LC-MS, and LC-CD.

A metabolic pathway of 2,3,10,11-oxygenated tetrahydroprotoberberines having the OH group on ring D was demonstrated. Metabolism of (13)C- or D(2)-labeled precursors was studied in cell cultures of Macleaya, Corydalis, and Nandina species. The structures of alkaloid metabolites obtained from feeding experiments were determined by application of combined LC-NMR, LC-MS/MS, and LC-CD techniques. (S)-Tetrahydropseudoprotoberberine (5) was stereospecifically O-methylated to the S-isomer (12) in cell cultures of three plant species. This S-isomer was further N-methylated to the (S)-alpha-N-methyl salt (15), which was oxidized to produce the pseudoprotopine-type alkaloid (10) in cell cultures of Macleaya and Corydalis species. These transformations were the same as those of 2,3,9,10-oxygenated protoberberines. The tetrahydropseudoprotoberberines (5, 6, and 12) were dehydrogenated to pseudoprotoberberines (13, 16, and 14), respectively. Both the R- and S-enantiomers of 5 were dehydrogenated in Macleaya cordata different from the case of 2,3,9,10-oxygenated protoberberines. Precursor 7, with OH groups at C-10 and C-11, was O-methylated at C-10 in M. cordata and C. ochotensis var. raddeana, which was distinct from O-methylation in N. domestica, in which 7 was O-methylated at both C-11 and C-10. Stereoselective O-demethylation [(S)-5 to (S)-18] occurred in N. domestica.

[Alkaloids from Dactylicapnos scandens Hutch].

OBJECTIVE: To investigate the alkaloids in the roots of Dactylicapnos scanden (D. Don) Hutch. METHOD: The compounds were isolated by various column chromatographic methods. The structures were elucidated by spectroscopic analysis. RESULT: Eight compounds were isolated and identified as d-isocorydine (1), protopine (2), d-magnoflorine (3), d-isocorydine-beta-N-oxide (4), d-corydine-alpha-N-oxide (5), d-corydine-beta-N-oxide (6), 6S, 6aS-N-methyllaurotetanine-alpha-N-oxide (7), and 6R, 6aS-N-methyllaurotetanine-beta-N-oxide (8). CONCLUSION: Compounds 4-8 were isolated from this species and the genus Dactylicapnos for the first time.

Alkaloids from Dactylicapnos scandens Hutch / 中国中药杂志

<p><b>OBJECTIVE</b>To investigate the alkaloids in the roots of Dactylicapnos scanden (D. Don) Hutch.</p><p><b>METHOD</b>The compounds were isolated by various column chromatographic methods. The structures were elucidated by spectroscopic analysis.</p><p><b>RESULT</b>Eight compounds were isolated and identified as d-isocorydine (1), protopine (2), d-magnoflorine (3), d-isocorydine-beta-N-oxide (4), d-corydine-alpha-N-oxide (5), d-corydine-beta-N-oxide (6), 6S, 6aS-N-methyllaurotetanine-alpha-N-oxide (7), and 6R, 6aS-N-methyllaurotetanine-beta-N-oxide (8).</p><p><b>CONCLUSION</b>Compounds 4-8 were isolated from this species and the genus Dactylicapnos for the first time.</p>

Discovery of the apoptosis-inducing activity and high accumulation of the butenolides, menisdaurilide and aquilegiolide in Dicentra spectabilis.

The occurrence of two butenolides, menisdaurilide and aquilegiolide, in commercial specimens of Dicentra spectabilis is reported for the first time; a rapid and direct isolation protocol is described. The ability of these lactones to induce apoptosis in human tumour cell lines at 10 microM concentration is also described. The high abundance and apoptosis-inducing activity reported here indicates that these constituents play a more significant role than the hormonal action previously attributed to them.

Diversification of CYCLOIDEA-like TCP genes in the basal eudicot families Fumariaceae and Papaveraceae s.str.

CYCLOIDEA-like genes belong to the TCP family of transcriptional regulators and have been shown to control different aspects of shoot development in various angiosperm lineages, including flower monosymmetry in asterids and axillary meristem growth in monocots. Genes related to the CYC gene from ANTIRRHINUM show independent duplications in both asterids and rosids. However, it remains unclear to what extent this affected the evolution of flower symmetry and shoot branching in these and other eudicot lineages. Here, we show that CYC-like genes have also undergone duplications in two related Ranunculales families, Fumariaceae and Papaveraceae s.str. These families exhibit morphological diversity in flower symmetry and inflorescence architecture that is potentially related to functions of CYC-like genes. We present sequences of 14 CYC-related genes covering 9 genera. Phylogenetic analyses indicate the presence of three clades of CYC-like genes. Shared motifs in the region between the TCP and R domains of CYC-like genes between Fumariaceae, Papaveraceae s.str., and AQUILEGIA (Ranunculaceae) indicate that the observed duplications originated from a single CYC gene present in all Ranunculales. RT-PCR expression data suggest that gene duplication and diversification in Fumariaceae and Papaveraceae s.str. was accompanied by divergence in expression patterns.

Synthesis and receptor binding evaluation of clavizepine analogues with no ring D substituents.

Assembly of the azepine ring of xantheno[9,1-cd]azepines by electrophilic cyclization of sulfonamide acetals provides access to clavizepine analogues in the form of 2,12b-dihydro- or 4-hydroxy-2,3,4,12b-tetrahydro-1H-xantheno[9,1-cd]azepines, in the latter case producing the trans derivative stereoselectively. Binding assays for clavizepine and analogues at adrenergic, dopaminergic, and serotonergic receptors are reported.

Antibacterial activity of the Chinese traditional medicine, Zi Hua Di Ding.

The antibacterial activity of extracts from species of plants used in the Chinese medicine, Zi Hua Di Ding (Viola yedoensis, V. prionantha, Corydalis bungeana and Gueldenstaedtia verna), was tested against Bacillus subtilis and Pseudomonas syringae using a bioautographic assay. The petroleum ether and ethyl acetate extracts of all four species of plants showed activity against both species of bacteria, whereas the methanol and aqueous methanol extracts were inactive. Three fractions from the petroleum ether extracts of V. yedoensis, V. prionantha and C. bungeana showed activity against B. subtilis at 6.25 microg/mL. Preliminary analysis of these active fractions indicates that they contain long chain carboxylic acids.

A new route to aristocularine alkaloids: total synthesis of aristoyagonine.

A short and efficient synthesis of aristocularines, involving the sequential construction of phosphorylated 4-alkoxyisoindolinones, Horner-type reaction, and ultimate cyclization by diaryl ether coupling, is disclosed. The success of this new conceptual approach is demonstrated by the total synthesis of the aristocularine alkaloid aristoyagonine.

Somatic embryogenesis and plant regeneration from seeds of wild Dicentra spectabilis (L.) LEM.

Regeneration via somatic embryogenesis from callus was studied in Dicentra spectabilis. To obtain somatic embryogenic callus, we cultured D. spectabilis seeds on MS basal media supplemented with various concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D). The highest percentage of embryogenic callus formation was observed on media containing 1.0 mg/l 2,4-D under dark conditions. Somatic embryogenesis was studied by transferring the callus onto MS basal medium containing different concentrations (0.0, 0.1, 0.5, 1.0, 2.0 mg/l) of KIN (kinetin) and/or BAP. Somatic embryogenesis on MS basal media with 1.0 mg/l of KIN was excellent under light conditions. Somatic embryos were rooted by transferring them to half-strength MS basal media containing 2 g/l Phytagel. About 64.2% of the somatic embryos converted to rooted plantlets, 4% showed secondary embryogenesis and 31.8% did not develop and died. Rooted plantlets showed a 46% survival rate when acclimatized ex vitro.