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Baihuasheshecao (Hedyotis diffusa), a Chinese herb for cancer treatment, is frequently adulterated by a related species Hedyotis corymbosa. DNA sequencing of the complete internal transcribed spacer region was applied to differentiate H. diffusa from H. corymbosa and other closely related species. The molecular data showed that four out of seven herb samples of Baihuasheshecao were adulterants. Chemical analyses by TLC and HPLC were used to authenticate H. diffusa and H. corymbosa. Two marker compounds were identified exclusively in H. diffusa: 6-O-(E)-p-coumaroyl scandoside methyl ester (compound 1) and 10(S)-hydroxypheophytin a (compound 2). Both compounds showed moderate anti-proliferation effect on PC3 human androgen-independent prostate cancer cells, while compound 2 also showed strong anti-proliferation effect on LNCaP human androgen-sensitive prostate cancer cells. Accordingly, these bioactive marker compounds could be applied to verify the authenticity and assess the quality of Baihuasheshecao.

Rhodomentosones A and B (1 and 2), two pairs of novel enantiomeric phloroglucinol trimers featuring a unique 6/5/5/6/5/5/6-fused ring system were isolated from Rhodomyrtus tomentosa. Their structures with absolute configurations were elucidated by NMR spectroscopy, X-ray crystallography, and ECD calculation. The bioinspired syntheses of 1 and 2 were achieved in six steps featuring an organocatalytic asymmetric dehydroxylation/Michael addition/Kornblum-DeLaMare rearrangement/ketalization cascade reaction. Compounds 1 and 2 exhibited promising antiviral activities against respiratory syncytial virus (RSV).

Puerarin (PU) is the most abundant isoflavone from the root of Pueraria lobata and exhibits a broad range of pharmacological activities. However, poor water solubility and low bioavailability limit its use. Enzymatic transglycosylation is emerging as a new strategy to improve the pharmacodynamic and pharmacokinetic properties of natural products for drug development. In this study, three PU glucosides (PU-G, PU-2G, and PU-3G) were synthesized by using a cyclodextrin glucanotransferase from Bacillus licheniformis with PU as the acceptor and α-cyclodextrin as the sugar donor. The transglycosylation products were isolated and structurally identified by mass spectrometry and nuclear magnetic resonance. The water solubilities of PU-G, PU-2G, and PU-3G were 15.6, 100.9, and 179.1 times higher than that of PU, respectively. Moreover, the antiosteoporosis activities of these glucosides were tested, and PU-G was found to show much more potent antiosteoporosis activity as compared to the original PU.

Three pairs of Securinega alkaloid epimers with a piperidin-2-yl moiety (1-6) were isolated from Flueggea suffruticosa, and their structures including absolute configurations were definitely characterized. An interconvertible C-2' epimerization process within each pair of epimers was observed. The following comprehensive experimental and theoretical investigations demonstrated an unusual stereochemical inversion mechanism of an N-substituted carbon stereogenic center, which was evidenced to be a protic solvent mediated process involving a tandem 1,4-elimination/1,4-addition as the key step.

Six new quassinoids (1–6) were isolated from the roots of Eurycoma longifolia, and their structures with absolute configurations were determined unambiguously by spectroscopic analyses and single-c...

A Gram-reaction-positive, endospore-forming and rod-shaped bacterial strain, designated py1325T, was isolated from the root of Paris polyphylla Smith var. yunnanensis collected from Yunnan Province, PR China, and subjected to a polyphasic taxonomic characterization. It grew optimally with 0–1 % NaCl (w/v), at pH 7 and at 30 °C. The major respiratory quinone was MK-7 and the diagnostic diamino acid in the cell-wall peptidoglycan was meso-diaminopimelic acid. The major cellular fatty acid was anteiso-C15 : 0. The polar lipids consisted of phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, two unidentified aminophospholipids, two unidentified phospholipids and two unidentified lipids. The results of 16S rRNA gene sequence analysis revealed the highest levels of sequence similarity with respect to Paenibacillus luteus R-3T (99.0 %), Paenibacillus sinopodophylli CCTCC AB 2016047T (97.9 %), Paenibacillus castaneae DSM 19417T (97.5 %) and Paenibacillus endophyticus LMG 27297T (97.2 %). The digital DNA–DNA hybridization and average nucleotide identity values between py1325T and these species ranged 20.6–53.3 % and 79.9–93.6 %. The G+C content of the genomic DNA was 47.7 mol%. According to the phylogenetic, phenotypic and chemotaxonomic evidence, strain py1325T clearly represents a novel species of the genus Paenibacillus , for which the name Paenibacillus paridis sp. nov. is proposed. The type strain is py1325T (=CCTCC AB 2015220T=LMG 29068T).

Two novel phloroglucinol-terpenoid adducts (1 and 2), featuring a rare 2,2,4-trimethyl-cinnamyl-β-triketone unit, were isolated from the buds of Cleistocalyx operculatus. Their structures with absolute configurations were established by spectroscopic analyses, single-crystal X-ray diffraction, and quantum chemical calculations. Structurally, compound 1 represents a new carbon skeleton possessing a densely functionalized tricyclo[11.3.1.03;8]heptadecane bridged ring system with an unusual bridgehead enol. Compounds 1 and 2 exhibited significant in vitro antiviral activities against respiratory syncytial virus (RSV).

A novel endophytic strain, designated as YIM B02564T, was isolated from the root of Paris polyphylla Smith var. yunnanensis obtained from Yunnan Province, southwest China. By using a polyphasic approach, cells of the strain were characterized as facultative anaerobic, Gram-positive and rod-shaped. The growth conditions of the strain were found to occur at 20–55 ℃ (optimum, 30 ℃), pH 6.0–9.0 (optimum, pH 7.0). Strain YIM B02564T can tolerate 2% NaCl concentration. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain YIM B02564T belonged to the genus Neobacillus and the 16S rRNA gene sequence similarity values of strain YIM B02564T to the type strains of members of this genus ranged from 95.6%–97.8%. The DNA G+C content of strain YIM B02564T calculated from the whole genome sequence was 41.6 mol%. Values of the ANI and the dDDH between strain YIM B02564T and its closely related Neobacillus species were below 77.87% and 21.50%. Strain YIM B02564T contained MK-7 as the major menaquinone, iso-C15:0 and anteiso-C15:0 as the major fatty acids. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, an unidentified aminophospholipid and four unidentified lipids. It contained meso-diaminopimelic acid in the cell-wall peptidoglycan. On the basis of polyphasic analysis, strain YIM B02564T could be differentiated genotypically and phenotypically from recognized species of the genus Neobacillus. The isolate therefore represents a novel species, for which the name Neobacillus paridis is proposed. The type strain is YIM B02564T (= JCM 34668T = CGMCC 1.18655T).

Background Isatidis Radix, the root of Isatis indigotica Fort. (Chinese woad) can produce a variety of efficacious compound with medicinal properties. The tetraploid I. indigotica plants exhibit superior phenotypic traits, such as greater yield, higher bioactive compounds accumulation and enhanced stress tolerance. In this study, a comparative transcriptomic and metabolomic study on Isatidis Radix autotetraploid and its progenitor was performed. Results Through the targeted metabolic profiling, 283 metabolites were identified in Isatidis Radix, and 70 polyploidization-altered metabolites were obtained. Moreover, the production of lignans was significantly increased post polyploidization, which implied that polyploidization-modulated changes in lignan biosynthesis. Regarding the transcriptomic shift, 2065 differentially expressed genes (DEGs) were identified as being polyploidy-responsive genes, and the polyploidization-altered DEGs were enriched in phenylpropanoid biosynthesis and plant hormone signal transduction. The further integrative analysis of polyploidy-responsive metabolome and transcriptome showed that 1584 DEGs were highly correlated with the 70 polyploidization-altered metabolites, and the transcriptional factors TFs-lignans network highlighted 10 polyploidy-altered TFs and 17 fluctuated phenylpropanoid pathway compounds. Conclusions These results collectively indicated that polyploidization contributed to the high content of active compounds in autotetraploid roots, and the gene–lignan pathway network analysis highlighted polyploidy–responsive key functional genes and regulators.

A combined strategy of building blocks recognition and molecular network construction, termed the building blocks-based molecular network (BBMN), was first presented to facilitate the efficient discovery of novel natural products. By mapping the BBMN of the total alkaloid fraction of Flueggea suffruticosa, three Securinega alkaloids (SEAs) with unusual chemical architectures, suffranidines A-C (1-3), were discovered and isolated. Compound 1 characterizes an unprecedented 8/5/6/5/6/6/6/6-fused octacyclic scaffold with a unique cage-shaped 3-azatricyclo[6.4.0.03,11 ]dodecane core. Compounds 2 and 3 are highly modified SEA dimers that incorporate additional C6 motifs. A hypothetical biosynthetic pathway for 1-3 was proposed. In addition, 1 significantly induced neuronal differentiation and neurite extension by upregulating eukaryotic elongation factor 2 (eEF2)-mediated protein synthesis.

A Gram-negative, yellow-pigmented, rod-shaped bacterial strain YIM B02567 T was isolated from the root of Paris polyphylla Smith var. yunnanensis in China. Strain YIM B02567 T grew optimally at 25–30°C and at pH 7.0 in the absence of NaCl on nutrient agar. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain YIM B02567 T belong to the genus Chryseobacterium , and closely related to Chryseobacterium piperi CTM T and Chryseobacterium soli DSM 19298 T . Whole genome sequencing indicated that the genome size was 4,774,612 bp and had a DNA G+C content of 34.5 %. Values of the ANI and the dDDH between strain YIM B02567 T and its closely related Chryseobacterium species were below 81.72 % and 24.7 %. Strain YIM B02567 T contained menaquinone-6 as the sole isoprenoid quinone, anteiso-C 15:0, iso-C 17:1 ω 9 c and iso-C 17:0 3-OH as major fatty acids and phosphatidylethanolamine as major polar lipid. Based on the polyphasic analyses, strain YIM B02567 T could be differentiated genotypically and phenotypically from recognized species of the genus Chryseobacterium . The isolate therefore represents a novel species, for which the name Chryseobacterium paridis sp. nov. is proposed. The type strain is YIM B02567 T (=CGMCC 1.18657 T =JCM 5426 T ).

International audience; For highly specialized insect herbivores, plant chemical defenses are often co-opted as cues for oviposition and sequestration. In such interactions, can plants evolve novel defenses, pushing herbivores to trade off benefits of specialization with costs of coping with toxins? We tested how variation in milkweed toxins (cardenolides) impacted monarch butterfly ( Danaus plexippus ) growth, sequestration, and oviposition when consuming tropical milkweed ( Asclepias curassavica ), one of two critical host plants worldwide. The most abundant leaf toxin, highly apolar and thiazolidine ring–containing voruscharin, accounted for 40% of leaf cardenolides, negatively predicted caterpillar growth, and was not sequestered. Using whole plants and purified voruscharin, we show that monarch caterpillars convert voruscharin to calotropin and calactin in vivo, imposing a burden on growth. As shown by in vitro experiments, this conversion is facilitated by temperature and alkaline pH. We next employed toxin-target site experiments with isolated cardenolides and the monarch’s neural Na + /K + -ATPase, revealing that voruscharin is highly inhibitory compared with several standards and sequestered cardenolides. The monarch’s typical >50-fold enhanced resistance to cardenolides compared with sensitive animals was absent for voruscharin, suggesting highly specific plant defense. Finally, oviposition was greatest on intermediate cardenolide plants, supporting the notion of a trade-off between benefits and costs of sequestration for this highly specialized herbivore. There is apparently ample opportunity for continued coevolution between monarchs and milkweeds, although the diffuse nature of the interaction, due to migration and interaction with multiple milkweeds, may limit the ability of monarchs to counteradapt.

Guided by 1H NMR spectroscopic experiments using the aromatic protons as probes, 11 macrocyclic diterpenes (1-11) were isolated from the aerial parts of Euphorbia helioscopia. Their full three-dimensional structures, including absolute configurations, were established unambiguously by spectroscopic analysis and single-crystal X-ray crystallographic experiments. Among the isolated compounds, compound 1 is the third member thus far of a rare class of Euphorbia diterpenes featuring an unusual 5/10 fused ring system, and 2-4 are new jatrophane diterpenes. Based on the NMR data of the jatrophane diterpenes obtained in this study as well as those with crystallographic structures reported in the literature, the correlations of the chemical shifts of the relevant carbons and the configurations of C-2, C-13, and C-14 of their flexible macrocyclic ring were considered. Moreover, the anti-inflammatory activities of 1-11 were investigated by monitoring their inhibitory effects on nitric oxide production in lipopolysaccharide-stimulated RAW 264.7 cells. Compound 1 showed an IC50 of 7.4 ± 0.6 μM, which might be related to the regulation of the NF-κB signaling pathway by suppressing the translocation of the p65 subunit and the consequent reduction of IL-6 and TNF-α secretions.

Drug discovery process and biological research critically depend on the access to libraries of molecules with interesting biomolecular properties. Thus, it is extremely important to develop robust and efficient strategies to access structurally diverse druglike compound collections. We introduce here a strategy for glycosylation of the total bufadienolides in Venenum Bufonis (VB) by using a permissive glycosyltransferase YjiC1 with conversion rates up to 90%, which was more efficient than other two enzymes. Compared to the crude extract, the glycosylated VB showed lower toxicity against zebrafish and more potent inhibitory activity on Na+,K+-ATPase. The results demonstrated the great advantages of using permissive enzymes as an alternative strategy for producing structurally diverse natural product-like libraries.

In order to understand variation characteristics of the soil available phosphorus and total nitrogen (TN) content around the roots of typical desert plants Peganum harmala Linn. (PHL) and Asterothamnus centrali-asiaticus (AC), which are widely distributed in Jinchang mining area of Gansu Province, the soil samples around the roots of the two plants were collected, and the contents of available phosphorus and TN were analyzed. The results showed that the change trend of soil available phosphorus content was not the same in the range of 0-60 cm around the roots of PHL and AC. In most areas the change of available phosphorus content in the soil from around the root of PHL was U-shaped, and the content of phosphorus around the roots of AC increased firstly and then decreased, while the change trends of TN content around AC was decreased gradually.

In 2005 edition of the Chinese Pharmacopoeia, lobetyolin was used as a marker for TLC identification of Radix Codonopsis, whose source plants are Codonopsis pilosula, C. pilosula var. modesta and C. tangshen. Quantification of lobetyolin in 44 samples derived from eight species of Codonopsis and another four genera of the same family Campanulaceae revealed that lobetyolin is present in all Codonopsis species and in Campanumoea javanica, Platycodon grandiflorum and Lobelia chinensis. In fact, the other five Codonopsis species are commonly used as the substitutes of Radix Codonopsis, and the roots of Campanumoea javanica and Platycodon grandiflorum are sometimes found as the adulterants. Contents of lobetyolin were found variable among different samples, and some substitutes and adulterants actually had comparably high contents of lobetyolin. Therefore, lobetyolin should be taken only as a general but not a definitive marker for the identification of Radix Codonopsis. HPLC-UV fingerprints with seven characteristic peaks were established for discriminating Radix Codonopsis from its adulterants, but more specific and definitive markers remain to be identified for differentiating Radix Codonopsis from its substitutes.

The new concept that Na/K-ATPase acts as a receptor prompted us to look for new ligands from Callicarpa kwangtungensis Chun. Using column chromatography, an undescribed phenethyl alcohol glycoside, callicarpanoside A, and an undescribed benzyl alcohol glycoside, callicarpanoside B, along with twelve known polyphenols were isolated from Callicarpa kwangtungensis Chun. All the isolated compounds were evaluated for their Na/K-ATPase (NKA) inhibitory activities. Using our NKA technology platform-based screening assay protocols, callicarpanoside B was identified as an undescribed Na/K-ATPase agonist. In particular, the newly identified benzyl alcohol glycoside was found to bind NKA and activate the receptor NKA/Src complex, resulting in the activation of protein kinase cascades. These cascades included extracellular signal-regulated kinases and protein kinase C epsilon, as well as NKA α1 endocytosis at nanomolar concentrations. Unlike the class of cardiotonic steroids, callicarpanoside B showed less inhibition of NKA activity and caused less cellular toxicity. Moreover, callicarpanoside B was found to bind NKA at a different site other than the cardiotonic steroids binding site. Thus, we have identified an undescribed NKA α1 agonist that may be used to enhance the physiological processes of NKA α1 signaling.

Ethnopharmacological relevance Seeds of Cardiocrinum giganteum var. yunnanense (Leichtlin ex Elwes) Stearn (Liliaceae), also known as Doulingzi, have been used as a folk substitute for conventional antitussive herb “Madouling” (Aristolochia species) to treat chronic bronchitis and pertussis. The active antitussive phytochemicals in C. giganteum seeds are not known. Aim of the study The present work aims at isolating the active phytochemicals in C. giganteum seeds and confirming their antitussive effects. Materials and methods Active chemicals were isolated from C. giganteum seeds ethanol extract and identified their structures. Antitussive effects were evaluated with the cough frequency of guinea pigs exposed to citric acid. Electrical stimulation of the superior laryngeal nerve in guinea pigs was performed to differentiate the acting site of potential antitussives. Results Two racemic biflavonoids (CGY-1 and CGY-2) were isolated from C. giganteum seeds. CGY-1 was identified as (S)-2″R,3″R- and (R)-2″S,3″S-dihydro-3″-hydroxyamentoflavone-7- methyl ether, which are new compounds and firstly isolated from C. giganteum seeds. Racemic CGY-2 was identified as (S)-2″R,3″R- and (R)-2″S,3″S-dihydro-3″-hydroxyamentoflavone. Both CGY-1 and CGY-2 could significantly inhibit coughs induced by inhalation of citric acid. Further, they acted on the peripheral reflex pathway to inhibit cough after electrical stimulation of the superior laryngeal nerve in guinea pigs. Conclusions These chemicals isolated from C. giganteum seeds showed good antitussive effects. The data provide scientific evidence to support the traditional use of C. giganteum seeds as an antitussive herbal medicine.

Four novel phloroglucinol derivatives (1-4) featuring a 2,4-dimethyl-cinnamyl-phloroglucinol moiety, along with their putative biosynthetic precursors 5 and 6, were isolated from the leaves of Cleistocalyx operculatus. Compounds 1 and 2 are two pairs of new enantiomeric phloroglucinol dimers possessing an unprecedented polycyclic skeleton with a highly functionalized dihydropyrano[3,2- d]xanthene tetracyclic core. Compounds 3 and 4 are two new phloroglucinol-terpene adducts (PTAs) with a novel carbon skeleton. The structures of 1-4 including their absolute configurations were unambiguously accomplished by combination of extensive spectroscopic analyses, X-ray crystallography, and quantum chemical ECD calculations. A hypothetical biosynthetic pathway for 1-4 was also proposed. Compound 1 exhibited a promising in vitro antiherpes simplex virus type-1 (HSV-1) effect.

A permissive steroid glycosyltransferase (UGT74AN1) from Asclepias curassavica exhibited robust capabilities for the regiospecific C3 glycosylation of cardiotonic steroids and C21 steroid precursors, and unprecedented promiscuity toward 53 structurally diverse natural and unnatural compounds to form O-, N-, and S-glycosides, along with the catalytic reversibility for a one-pot transglycosylation reaction. These findings highlight UGT74AN1 as the first regiospecific catalyst for cardiotonic steroid C3 glycosylation and exhibit significant potential for glycosylation of diverse bioactive molecules in drug discovery.

Three pairs of new flavonostilbene enantiomers, cajanusflavanols A-C (1-3), along with their putative biogenetic precursors 4-6, were isolated from Cajanus cajan. Compound 1 possesses an unprecedented carbon skeleton featuring a unique highly functionalized cyclopenta[1,2,3-de]isobenzopyran-1-one tricyclic core. Compounds 2 and 3 are the first examples of methylene-unit-linked flavonostilbenes. Their structures with absolute configurations were elucidated by spectroscopic analyses, X-ray diffraction, and computational calculations. Compounds 1 and 2 exhibited significant in vitro anti-inflammatory activities.

Solidago canadensis is a malignant invasive plant widely distributed in China. In this study, it was used as a biomass source to prepare biochar via an oxygen-limited pyrolysis method. The effect of temperature, heating rate and pyrolysis time on the yield and surface characteristics of the biochar was identified. The adsorption properties for dimethyl phthalate (DMP), a typical allelochemical of Solidago canadensis, of the biochar were explored. In addition, a pot experiment was conducted to reveal the effect of the biochar on tomato seed germination in the presence of allelochemicals. The maximum yield of the biochar was observed when Solidago canadensis was pyrolyzed at 300 °C for 2 h, with a heating rate of 8 °C min−1. Variation of pyrolysis conditions had little influence on the surface characteristics of the biochar. The adsorption of DMP on the biochar could be well described by the Langmuir model, with a maximum adsorption capacity of 59.37 mg kg−1. The addition of biochar to the soil could promote tomato seed germination in the presence of allelochemicals. Therefore, the biochar prepared from Solidago canadensis can be used for soil amendment for invaded sites.

Flueggeacosines A-C (1-3), three dimeric securinine-type alkaloid analogues with unprecedented skeletons, were isolated from Flueggea suffruticosa. Compounds 1 and 2 are the first examples of C-3-C-15' connected dimeric securinine-type alkaloids. Compound 3 is an unprecedented heterodimer of securinine-type and benzoquinolizidine alkaloids. Biosynthetic pathways for 1-3 were proposed on the basis of the coexisting alkaloid monomers as the precursors. Compound 2 exhibited significant activity in promoting neuronal differentiation of Neuro-2a cells.

Certain biflavonoids have been proven to protect against cognitive dysfunction. A new biflavonoid, CGY-1, isolated from Cardiocrinum giganteum seeds, has not yet been reported to have any neuroprotective effect. In this study, a scopolamine-induced memory deficit model was used to explore the neuroprotective effect of CGY-1. Behavioral experiments, such as tests using the Morris water maze, the Y-maze and the fear conditioning test, were conducted. The results revealed that oral administration of CGY-1 (20 and 40 mg/kg) and donepezil shortened the escape latency, improved the percentage of spontaneous alternation, and increased the freezing times, respectively. CGY-1 decreased the levels of reactive oxygen species and malondialdehyde and increased the activities of superoxide dismutase and glutathione peroxidase in the hippocampus. In addition, CGY-1 decreased the activity of acetylcholinesterase and increased the activities of choline acetyltransferase and acetylcholine in the hippocampus. Furthermore, qPCR and western blot results revealed that the expressions of neurotrophic factors, brain-derived neurotrophic factor and nerve growth factor were upregulated in the hippocampus after CGY-1 treatment. In conclusion, CGY-1 could be a promising candidate for the treatment of cognitive dysfunction.

The phytochemical investigation on the fruits of Flueggea virosa resulted in the discovery of two new norsecurinine-derived alkaloid dimers, norsecurinamines A and B (1 and 2). Compound 1 is the first hetero-dimeric alkaloid possessing norsecurinine and donaxaridine units, and 2 represents the first example of NH-linked dimeric Securinega alkaloid. Their structures and absolute configuration were elucidated on the basis of extensive spectroscopic analysis as well as single-crystal X-ray diffraction method. A plausible biogenetic pathway of 1 was also proposed.

Nine new melodinus-type alkaloids, melohemsines A-I (1–9), together with eight known ones were isolated from Melodinus hemselyanus. The structures of the new alkaloids, including their absolute configurations, were elucidated on the basis of comprehensive spectroscopic and electronic circular dichroism (ECD) analyses and X-ray diffraction. Compound 1 is the first melodinus-type alkaloid with a 6/6/5/5/6/3 hexacyclic ring skeleton system. Compounds 2–3 are the first natural melodinus-type alkaloids with a reduction in two carbon units at C-20.

Objective To study the chemical constituents from the roots of Rubus parvifolius. Methods The chemical constituents were extracted and purified by silica gel column chromatography. NMR spectra were used for structural identification. Results Phytochemical study on the roots of R. parvifolius led to the isolation of one ceramide (1), two anthraquinones (2 and 3), four triterpenoids (4-7), two flavonoids (8 and 9), one fatty acid ester (10), and two sterols (11 and 12). Conclusion Compound 1 is isolated from the plants of family Rosaceae for the first time, and compounds 2-5 are isolated from genus Rubus for the first time. Though R. parvifolius shares the same major chemical types (triterpenoid, flavonoid, and anthraquinone) with those of R. alceaefolius, a substituent of R. parvifolius, their individual constituents are different. In addition, R. parvifolius contains ceramide (1) with high concentration, while caffeoylquinic acid reported in R. alceaefolius has not been found in R. parvifolius. Furthermore, the results from our phytochemical study are consistent with the DNA phylogenic relationship between R. parvifolius and R. alceaefolius (two separated subgenera), suggesting that the substitution of the former species with the latter one in folk medicine might not be suitable.

Phytochemical investigation of Helleborus thibetanus led to the isolation of two new bufadienolides with a trans A/B ring fusion mode (1–2) and two known ones (3–4), three podophyllotoxins (5–7), two flavones (8 and 9), one phytoecdysteroid (10), one spirostane (11) and one pseudo-spirostane (12). The structures of the new compounds were identified using extensive spectroscopic analyses and the known compounds were identified by comparing the spectral data with those previously reported. Isolation of bufadienolides with a trans A/B ring fusion mode could be chemotaxonomic marker for the differentiation of H. thibetanus from the toad venom and other plants of this genus, on the other hand, co-occurrence of podophyllotoxin from H. thibetanus supported the inclusion of Berberidaceae and Ranunculaceae in the same monophyletic order Ranunculales based on the outgroup comparison and parsimony analysis.

Phytochemical investigations on Physalis. alkekengi L. var. franchetii, a widespread traditional Chinese medicine, led to the isolation and identification of three new sesquiterpenoids physalisitins A–C (1–3). Their structures were elucidated by NMR and HRESIMS analysis, and their absolute configurations were determined by quantum chemical NMR and ECD calculations, as well as by comparing their optical rotation values with those known analogues. All of the isolated compounds were evaluated for their cyclooxygenase-2 (COX-2) inhibitory activity. Compounds 1–3 dose-dependently inhibited the COX-2 enzyme with IC50 values of 3.22 ± 0.25, 6.35 ± 0.84, and 11.13 ± 1.47 μM, respectively.

To enhance the structural diversity of isoflavonoids and provide more derivatives for the biological screening, a semisynthetic mixture was generated by diversification of the crude extract of Radix puerariae (Pueraria montana var. lobata) through the chemical reaction with hydrazine hydrate. Eleven 3,4-diarylpyrazoles (1-11) and two 5-phenyl-6-benzyldihydropyridazinones (12 and 13) were isolated from the semisynthetic mixture, and their structures were identified by spectroscopic methods in combination with X-ray crystallographic analysis. Among them, nine compounds (5-13) were new derivatives. All the compounds were evaluated on the inhibitory activities against the prostate cancer cell lines LNCaP and PC3. Compounds 12 and 13 were found to exhibit much more potent inhibitory activities against the androgen dependent LNCaP cells than the androgen independent PC3 cells. Rapid synthesis of new 3,4-diarylpyrazoles and two 5-phenyl-6-benzyldihydropyridazinones with significant biological activity highlights the great potential of one-pot combinatorial modification for the diversification of natural products.

Three new 6,6-spiroketal polyketides, streptospirodienoic acids A (1), B (2) and streptospirodienoate A (3), were obtained from the fermentation broth of Streptomycetes sp. (no. 0950134). Their structures were constructed by one 6,6-spiroketal core coupled with hexadienoic acid, in which the starter unit might be 2-methylpropionyl-CoA. Their chemical structures were determined by detailed analyses of UV, IR, HRESIMS, 1D, 2D-NMR spectroscopic data and the X-ray crystallography technique. The biosynthetic pathway for 1 and 2 was proposed. Compound 3 showed moderate cytotoxic activity against HCT-116 cells (IC50 = 5.2 μM), while compounds 1 and 2 showed no activity (IC50 > 10.0 μM).

Six cycloheptadepsipeptides, marformycins A-F (1-6), featuring a unique N-terminally formylated side chain and five non-proteinogenic amino acid residues, were isolated from the deep Sea-derived Streptomyces drozdowiczii SCSIO 10141. The previously unsolved absolute stereochemistry of 3 and 4 was determined and the structures of other four new congeners were elucidated by extensive spectroscopic, chiral-phase HPLC, and single-crystal X-ray diffraction analyses. Compounds 1-5 bear no cytotoxicity against a number of human tumor cell lines but show selective anti-infective activity against Micrococcus luteus. (C) 2014 Elsevier Ltd. All rights reserved.

In this study, the non-specific immunostimulatory effect of alginate oligosaccharides (AOSs) with three types of molecular weights, namely, A 1 = below 1 kD (polymerization of 2–5), A 2 = 1 kD to 2 kD (polymerization of 5–10), and A 3 = 2 kD to 4 kD (polymerization of 10–20), as well as their two types of corresponding purified uronic acid oligomers (mannuronate and guluronate oligomers) on sea cucumber ( Apostichopus japonicus ) coelomocyte were investigated in vitro. Coelomocytes cultured in L-15 medium containing different AOS concentrations (0, 50, 100, 200, or 400 μg mL − 1 ) were sampled, and non-specific immune responses, such as phagocytic capacity, reactive oxygen species, lysozyme activity, peroxidase activity, total nitric oxide synthase and acid phosphatase activity were determined and compared with those of the control samples (i.e., treatments without immunostimulants) after exposure to AOS for 3, 6, 12, or 24 h. Most of the above mentioned immune parameters were significantly ( P 1 group showed better effects on phagocytic capacity, lysozyme activity, peroxidase activity and total nitric oxide synthase of coelomocytes because of the higher increase, earlier appearance, and longer duration time than those of the A 2 and A 3 groups. Furthermore, among the significant differences of various molecular weights of the AOS groups relative to the control sample, these immune parameters in mannuronate or guluronate oligomer groups were all significantly higher than those in the control sample ( P 1 mannuronate group had a higher increase in phagocytic activity than that of guluronate, and no significant difference was observed in other immune parameters between corresponding mannuronate and guluronate oligomer groups. These results indicated that AOS could enhance the non-specific immune response of sea cucumber coelomocytes in vitro and provided basic information regarding AOS as a potential immunostimulant in sea cucumber culture.

One new stenine-type alkaloid, tuberostemonine D ( 1 ), together with five known stenine-type alkaloids ( 2 – 6 ) and two known stemoninine-type alkaloids ( 7 and 8 ), were isolated from the roots of Stemona tuberosa . Their structures were elucidated by extensive spectroscopic methods (IR, UV, MS, 1D and 2D NMR), and the structure of 1 was further confirmed by X-ray diffraction analysis. First simultaneous isolation of stenine- and stemoninine-type alkaloids not only added a new chemical type and increased the chemical diversity of Stemona tuberosa , but also provided chemotaxonomic clues for the close relationship between genera Stemona and Stichoneuron , and favored retaining them in the same family.

Phytochemical investigation on the fruits of Flueggea suffruticosa resulted in the isolation of three new Securinega alkaloids, secu'amamine H (1), 15β-methoxy-14,15-dihydrosecurinine (3), and securinol E (7), as well as eight known ones (2, 4-6, and 8-11). Their structures were elucidated by means of spectroscopic techniques (1D and 2D NMR, MS, UV, and IR). The absolute configurations of the new compounds were established by single-crystal X-ray diffraction and CD analyses.

Suffrutines A (1) and B (2), a pair of novel photochemical Z/E isomeric indolizidine alkaloids, with a unique and highly conjugated C20 skeleton, were isolated from the roots of Flueggea suffruticosa. The structures were elucidated by extensive analysis of NMR spectra and single-crystal X-ray diffraction. The light-induced isomerization and hypothetical biogenetic pathway to 1 and 2, as well as their activity for regulating the morphology of Neuro-2a cells are also discussed.

A pair of new enantiomeric isoquinoline alkaloids, (+)- and (−)-5-hydroxyl-8-oxyberberine (1), along with nine known analogs (2–10) were isolated from the rhizoma of Coptis chinensis. Their structures with absolute configurations were elucidated on the basis of spectroscopic methods, X-ray diffraction analysis, and quantum chemical calculation. The antibacterial activities of 1–10 were also evaluated. Berberine (8) displayed synergism against methicillin-resistant Staphylococcus aureus (MRSA) in combination with ceftazidime and cefepiem.

Five new cardenolide lactates (1–5) and one new dioxane double linked cardenolide glycoside (17) along with 15 known compounds (6–16 and 18–21) were isolated from the ornamental milkweed Asclepias curassavica. Their structures were elucidated by extensive spectroscopic methods (IR, UV, MS, 1D- and 2D-NMR). The molecular structures and absolute configurations of 1–3 and 17 were further confirmed by single-crystal X-ray diffraction analysis. Simultaneous isolation of dioxane double linked cardenolide glycosides (17–21) and cardenolide lactates (1–5) provided unique chemotaxonomic markers for this genus. Compounds 1–21 were evaluated for the inhibitory activities against DU145 prostate cancer cells. The dioxane double linked cardenolide glycosides showed the most potent cytotoxic effect followed by normal cardenolides and cardenolide lactates, while the C21 steroids were non-cytotoxic. Enzymatic assay established a correlation between the cytotoxic effects in DU145 cancer cells and the Ki for the inhibition of Na(+),K(+)-ATPase. Molecular docking analysis revealed relatively strong H-bond interactions between the bottom of the binding cavity and compounds 18 or 20, and explained why the dioxane double linked cardenolide glycosides possessed higher inhibitory potency on Na(+),K(+)-ATPase than the cardenolide lactate.

This feeding trial was conducted to determine the vitamin E requirement of sea cucumber (Apostichopus japonicus) and to study the effects of vitamin E on nonspecific immune parameters. Commercial sea cucumber diets supplemented with 0, 50, 100, 200, 500 or 1000 mg kg−1 vitamin E were fed to juvenile sea cucumber (7.96 ± 0.01 g) for 60 days. Specific growth rate and total coelomocyte counts were maximized in sea cucumber fed diets supplemented with 100 mg kg−1 vitamin E. Reactive oxygen species production was maximized at 50 mg kg−1 vitamin E, whereas superoxide dismutase activity was the highest in sea cucumber fed diets supplemented with 100 mg kg−1 vitamin E. The vitamin E concentration in the body wall of the sea cucumber increased as the vitamin E level in the diet increased. Analysis of specific growth rate and total coelomocyte counts of the sea cucumber indicated that 88–92 mg kg−1 vitamin E is required for maximal growth and nonspecific immune responses of A. japonicus and that 114.7 mg kg−1 vitamin E is required to minimize lipid peroxidation levels.

Two pairs of new enantiomeric benzofurans with unusual skeletons, (+)- and (−)-eupachinin A (1), as well as (+)- and (−)-eupachinin B (2), were isolated from the roots of Eupatorium chinense by chiral HPLC. Their structures with absolute configurations were elucidated on the basis of spectroscopic methods, X-ray diffraction analysis, and quantum chemical calculation. The plausible biogenetic pathway of 1 and 2 was also proposed.

Herein we report the discovery of a novel lead compound, oxyphylla A [(R)-4-(2-hydroxy-5-methylphenyl)-5-methylhexanoic acid] (from the fruit of Alpinia oxyphylla), which functions as a neuroprotective agent against Parkinson's disease. To identify a shortlist of candidates from the extract of A. oxyphylla, we employed an integrated strategy combining liquid chromatography/mass spectrometry, bioactivity-guided fractionation, and chemometric analysis. The neuroprotective effects of the shortlisted candidates were validated prior to scaling up the finalized list of potential neuroprotective constituents for more detailed chemical and biological characterization. Oxyphylla A has promising neuroprotective effects: (i) it ameliorates in vitro chemical-induced primary neuronal cell damage and (ii) alleviates chemical-induced dopaminergic neuron loss and behavioral impairment in both zebrafish and mice in vivo. Quantitative proteomics analyses of oxyphylla A-treated primary cerebellar granule neurons that had been intoxicated with 1-methyl-4-phenylpyridinium revealed that oxyphylla A activates nuclear factor-erythroid 2-related factor 2 (NRF2)-a master redox switch-and triggers a cascade of antioxidative responses. These observations were verified independently through western blot analyses. Our integrated metabolomics, chemometrics, and pharmacological strategy led to the efficient discovery of novel bioactive ingredients from A. oxyphylla while avoiding the nontargeting, labor-intensive steps usually required for identification of bioactive compounds. Our successful development of a synthetic route toward oxyphylla A should lead to its availability on a large scale for further functional development and pathological studies.

Six new pentacyclic triterpenoids were isolated from the fruit of Camptotheca acuminata. The chemical structures of the new compounds were elucidated by extensive spectroscopic analysis including HR-ESI-MS, IR, UV, 1D- and 2D-NMR. Moreover, the antibacterial activities of compounds 1, 2, 4, 5, and 6 were evaluated against Staphylococcus aureus, Escherichia coli, Bacillus subtilis and Dickeya zeae. All these tested compounds showed moderate antibacterial activity against Bacillus subtilis and Dickeya zeae.

The antibacterial activities of compounds (I) and (II) are evaluated, and (I) is shown to exhibit moderate activity.

A pair of new alkaloid stereo-isomers, stemocochinin (1) and isostemocochinin (2), was obtained from the roots of Stemona japonica Miq., along with seven known alkaloids, stemonamine (3), isostemonamine (4), maistemonine (5), isomaistemonine (6), croomine (7), stemonine (8), and protostemonine (9). The complete structure and stereochemistry of the pair of isomers were established by extensive analysis of the spectral data. Furthermore, our results indicated that S. japonica is chemically closer to S. sessilifolia than S. tuberosa, which are consistent with our previous DNA study on Stemona species.

Pseudoguaianolide sesquiterpene lactones minimolides A (1), B (2), C (3) and D (4) and two guaianolide sesquiterpene lactones minimolides E (5) and F (6), along with seven known ones (7-13), were isolated from the supercritical fluid extract of Centipeda minima. The structures of these compounds were elucidated by extensive spectroscopic methods (IR, UV, HRESIMS, 1D-NMR and 2D-NMR), and the complete structure and stereochemistry of 1 was further confirmed by X-ray diffraction analysis. Compounds 1, 5-8,11 and 13 displayed inhibitory activity against human nasopharyngeal cancer cells (CNE) with IC(50) values ranging from 1.1 to 20.3 μM. Compound 13 containing both α-methylene-γ-lactone and α, β-unsaturated cyclopentenone moieties exhibited even stronger inhibitory activity than that of cisplatin (positive control) through cell cycle arrest at G2/M phase. Isolation of six sesquiterpene lactones from Centipeda minima highlighted the potential of supercritical fluid extraction for enrichment of minor constituents for phytochemical study.

Tydemania expeditionis Weber-van Bosse (Udoteaceae) is a weakly calcified green alga. In the present paper, liquid chromatography coupled with photodiode array detection and electrospray mass spectrometry was developed to identify the fingerprint components. A total of four triterpenoid sulfates and three hydroxy fatty acids in the ethyl acetate fraction of the crude extract were structurally characterized on the basis of retention time, online UV spectrum, and mass fragmentation pattern. Furthermore, a detailed liquid chromatography-mass spectrometry analysis revealed two new hydroxy fatty acids, which were then prepared and characterized by extensive nuclear magnetic resonance (NMR) analyses. The proposed method provides a scientific and technical platform for the rapid identification of triterpenoid sulfates and hydroxy fatty acids in similar marine algae and terrestrial plants.

Two new antimycin antibiotics; that is antimycins A(19) (1) and A(20) (2), were isolated from a cultured broth of marine actinomycete Streptomyces antibioticus H74-18 together with antimycins A(1a) (3a) and A(1b) (3b), A(2a) (4), A(3a) (5a) and A(3b) (5b). Their structures were determined by spectroscopic methods in combination with X-ray diffraction. Antimycin A(19) possessed a chiral acyl chain and an alkyl branch. The absolute configuration of chiral acyl chain in 1 was determined by X-ray diffraction analysis. Antimycin A(20) (2) has the shortest and simplest acetoxy acyl chain in the antimycins family. All the antimycins (1-5) showed potential antifungal activities against Candida albicans with MIC of about 5-10 μg ml(-1).

A new ursane-type triterpenoid (1), together with 15 known compounds (2-16), was isolated from the barks of Schefflera heptaphylla (L.) Frodin. The structure of the new compound was determined on the basis of extensive spectroscopic data including IR, HR-ESI-MS, 1D and 2D NMR, and further confirmed by single-crystal X-ray diffraction. Compounds 2-6 were isolated from Schefflera genus for the first time.

Aims of the study Stemona alkaloids with distinctly different chemical skeletons are recently reported as the active components in the antitussive herb Baibu derived from the root-tubers of Stemona tuberosa . This study aims to determine if alkaloids of this herb contribute equally to the antitussive functions, act on the same sites of cough reflex, and play any role in inducing central respiratory depressant effects. Materials and methods Antitussive potency of four major alkaloids was evaluated on guinea pigs with citric acid aerosol to induce cough. The action sites of the alkaloids on cough reflex pathway were tested with electrical stimulation of the superior laryngeal nerve in guinea pigs. The central respiratory effects of croomine were also tested on guinea pigs. Results Croomine, neotuberostemonine and stemoninine showed similar antitussive potency, while tuberostemonine showed much weaker antitussive potency. Neotuberostemonine, tuberostemonine and stemoninine acted on the peripheral cough reflex pathway, while croomine acted on the central part. Croomine also showed obvious central respiratory depressant effects. Conclusions The four major Stemona alkaloids in Stemona tuberosa do not contribute equally to antitussive potency in guinea pigs. Neotuberostemonine, tuberostemonine and stemoninine target on peripheral cough reflex pathway. Croomine acts on central sites in the cough reflex pathway and demonstrates central respiratory depressant effects, which can partly account for the adverse reactions reported for the herb.