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Phytochemistry

Current research reports and chronological list of recent articles..




Phytochemistry is the international scientific journal of pure and applied plant chemistry, plant biochemistry and molecular biology. It is also a is a primary source for papers dealing with plant secondary compounds, especially with regard to their biosynthesis and diverse properties.

The publisher is Elsevier. The copyright and publishing rights of specialized products listed below are in this publishing house. This is also responsible for the content shown.

To search this web page for specific words type "Ctrl" + "F" on your keyboard (Command + "F" on a Mac). Then: type the word you are searching for in the window that pops up!

Additional research articles see Current Chemistry Research Articles. Magazines with similar content (phytochemistry):

 - Phytochemical Analysis.

 - Phytochemistry Letters.

 - Phytochemistry Reviews.



Phytochemistry - Abstracts



Biochemical characterization of microbial type terpene synthases in two closely related species of hornworts, Anthoceros punctatus and Anthoceros agrestis

Publication date: May 2018
Source:Phytochemistry, Volume 149
Author(s): Wangdan Xiong, Jianyu Fu, Tobias G. Köllner, Xinlu Chen, Qidong Jia, Haobo Guo, Ping Qian, Hong Guo, Guojiang Wu, Feng Chen
Microbial terpene synthase-like (MTPSL) genes are a type of terpene synthase genes only recently identified in plants. In contrast to typical plant terpene synthase genes, which are ubiquitous in land plants, MTPSL genes appear to occur only in nonseed plants. Our knowledge of catalytic functions of MTPSLs is very limited. Here we report biochemical characterization of the enzymes encoded by MTPSL genes from two closely related species of hornworts, Anthoceros punctatus and Anthoceros agrestis. Seven full-length MTPSL genes were identified in A. punctatus (ApMTPSL1-7) based on the analysis of its genome sequence. Using homology-based cloning, the apparent orthologs for six of the ApMTPSL genes, except ApMTPSL2, were cloned from A. agrestis. They were designated AaMTPSL1, 3–7. The coding sequences for each of the 13 Anthoceros MTPSL genes were cloned into a protein expression vector. Escherichia coli-expressed recombinant MTPSLs from hornworts were assayed for terpene synthase activities. Six ApMTPSLs and five AaMTPSLs, except for ApMTPSL5 and AaMTPSL5, showed catalytic activities with one or more isoprenyl diphosphate substrates. All functional MTPSLs exhibited sesquiterpene synthase activities. In contrast, only ApMTPSL7 and AaMTPSL7 showed monoterpene synthase activity and only ApMTPSL2, ApMTPSL6 and AaMTPSL6 showed diterpene synthase activity. Most MTPSLs from Anthoceros contain uncanonical aspartate-rich motif in the form of either ‘DDxxxD’ or ‘DDxxx’. Homology-based structural modeling analysis of ApMTPSL1 and ApMTPSL7, which contain ‘DDxxxD’ and ‘DDxxx’ motif, respectively, showed that ‘DDxxxD’ and ‘DDxxx’ motifs are localized in the similar positions as the canonical ‘DDxxD’ motif in known terpene synthases. To further understand the role of individual aspartate residues in the motifs, ApMTPSL1 and ApMTPSL7 were selected as two representatives for site-directed mutagenesis studies. No activities were detected when any of the conserved aspartic acid was mutated into alanine. This study provides new information about the catalytic functions of MTPSLs and the functionality of their uncanonical aspartate-rich motifs, and builds a knowledge base for studying the biological importance of MTPSL genes and their terpene products in nonseed plants.

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Datum: 25.04.2018


Editorial Board/Publication Information

Publication date: May 2018
Source:Phytochemistry, Volume 149




Datum: 25.04.2018


Saponins from seeds of Genus Camellia: Phytochemistry and bioactivity

Publication date: May 2018
Source:Phytochemistry, Volume 149
Author(s): Na Guo, Tuantuan Tong, Ning Ren, Youying Tu, Bo Li
Camellia seeds have been traditionally used as oil raw materials in Asia, and are known for a wide spectrum of applications. Oleanane-type triterpene saponins are the major specialised metabolites in Camellia seeds, and more than seventy saponins have been isolated and characterized. These natural compounds have caught much attention due to their various biological and pharmacological activities, including modulation of gastrointestinal system, anti-cancer, anti-inflammation, anti-microorganism, antioxidation, neuroprotection, hypolipidemic effects, foaming and detergence, as well as helping the accumulation of pollutants by plants. These compounds have a promising application in medicine, agriculture, industry and environmental protection. The present paper summarized the information from current publications on Camellia seed saponins, with a focus on the advances made in chemical structures, determination methods, bioactivities and toxicity. We hope this article will stimulate further investigations on these compounds.

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Datum: 25.04.2018


Aims and Scope

Publication date: May 2018
Source:Phytochemistry, Volume 149




Datum: 25.04.2018


Graphical Contents List

Publication date: April 2018
Source:Phytochemistry, Volume 148




Datum: 25.04.2018


Seco-labdane diterpenoids from the leaves of Callicarpa nudiflora showing nitric oxide inhibitory activity

Publication date: May 2018
Source:Phytochemistry, Volume 149
Author(s): Xiaocong Sun, Feng Liu, Xueyuan Yang, Jinghan Wang, Bangjian Dong, Chunfeng Xie, Da-Qing Jin, Jie Zhang, Dongho Lee, Yasushi Ohizumi, Jing Xu, Yuanqiang Guo
Nine previously undescribed seco-labdane diterpenoids, nudiflopenes A−I, were isolated from the leaves of Callicarpa nudiflora. Their structures were elucidated on the basis of extensive 1D and 2D NMR spectroscopic data analysis, and the absolute configurations of these compounds were established by the modified Mosher's method and experimental and calculated electronic circular dichroism spectra. Nudiflopenes A−I belong to the class of seco-labdane diterpenoids. All of the isolates showed inhibitory activities on lipopolysaccharide-induced nitric oxide (NO) production in murine microglial BV-2 cells. The possible mechanism of NO inhibition of some bioactive compounds was also investigated using molecular docking, which revealed interactions of bioactive compounds with the inducible nitric oxide synthase (iNOS) protein.

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Datum: 25.04.2018


An OMIC approach to elaborate the antibacterial mechanisms of different alkaloids

Publication date: May 2018
Source:Phytochemistry, Volume 149
Author(s): Fatma Gizem Avci, Nihat Alpagu Sayar, Berna Sariyar Akbulut
Plant-derived substances have regained interest in the fight against antibiotic resistance owing to their distinct antimicrobial mechanisms and multi-target properties. With the recent advances in instrumentation and analysis techniques, OMIC approaches are extensively used for target identification and elucidation of the mechanism of phytochemicals in drug discovery. In the current study, RNA sequencing based transcriptional profiling together with global differential protein expression analysis was used to comparatively elaborate the activities and the effects of the plant alkaloids boldine, bulbocapnine, and roemerine along with the well-known antimicrobial alkaloid berberine in Bacillus subtilis cells. The transcriptomic findings were validated by qPCR. Images from scanning electron microscope were obtained to visualize the effects on the whole-cells. The results showed that among the three selected alkaloids, only roemerine possessed antibacterial activity. Unlike berberine, which is susceptible to efflux through multidrug resistance pumps, roemerine accumulated in the cells. This in turn resulted in oxidative stress and building up of reactive oxygen species, which eventually deregulated various pathways such as iron uptake. Treatment with boldine or bulbocapnine slightly affected various metabolic pathways but has not changed the growth patterns at all.

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Datum: 25.04.2018


LC-MS guided isolation of sinodamines A and B: Chimonanthine-type alkaloids from the endangered ornamental plant Sinocalycanthus chinensis

Publication date: July 2018
Source:Phytochemistry, Volume 151
Author(s): Guang-Lei Ma, Juan Xiong, Ezzat E.A. Osman, Ting Huang, Guo-Xun Yang, Jin-Feng Hu
Two previously undescribed chimonanthine-type [sinodamines A and B] and five related known dimeric tryptamine-derived alkaloids were isolated and characterized from the leaves of the endangered ornamental plant Sinocalycanthus chinensis under the guidance of LC-MS detection and dereplication analyses, along with conventional isolation procedures. Their structures were established on the basis of spectroscopic methods and chemical transformations. Sinodamine A can be regarded as the naturally occurring N-oxide derivative of its pseudo-mesomer sinodamine B. An acid-catalyzed Meisenheimer rearrangement from sinodamine A to its oxazine-form with a final equilibrium of 1:2 was observed by monitoring their NMR spectra. (−)-Folicanthine showed significant cytotoxicity against human lung carcinoma A549 and colorectal carcinoma HT29 cells, with IC50 values of 7.76 and 6.16 μM, respectively.

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Datum: 25.04.2018


Trijugin- and mexicanolide-type limonoids from the fruits of Heynea trijuga that reverse multidrug resistance in MCF-7/DOX cells

Publication date: July 2018
Source:Phytochemistry, Volume 151
Author(s): Fa-Liang An, Dong-Mei Sun, Rui-Zhi Wang, Ming-Hua Yang, Jun Luo, Ling-Yi Kong
Eleven previously undescribed limonoids, trichisins A-K, including eight structural analogues A-H of trijugin and three H-J mexicanolide derivatives, together with two known mexicanolide derivatives were isolated from the fruits of Heynea trijuga Roxb. ex Sims. The structure determination was based on extensive physical data analyses (NMR, MS), and their basic skeletons and the absolute configurations of trichisins A, B, E, K and trichiconnarone A were assigned via X-ray crystallographic analysis (Cu Kα radiation). The hemiketal motifs in trijugins A, B, and E-G are rare in limonoids. Bioactivity screenings suggested that the trijugin H and mexicanolide-type trichiconnarones A and B limonoids were effective in reversing resistance in MCF-7/DOX cells at a nontoxic concentration of 50 μM with IC50 values of 12.45, 10.86, and 14.96 μM, respectively.

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Datum: 25.04.2018


Resin glycosides from the seeds of Ipomoea muricata and their multidrug resistance reversal activities

Publication date: May 2018
Source:Phytochemistry, Volume 149
Author(s): Wen-qiong Wang, Shan-shan Liu, Wei-bin Song, Jun Li, Li-jiang Xuan
Resin glycosides represent an important chemotaxonomic marker of the Convolvulaceae family and possess multidrug resistance (MDR) reversal activity. In our recent study, nine previously undescribed resin glycosides, Calonyctins B–J, were isolated from the seeds of Ipomoea muricata. Their structures with the absolute configuration were established on the basis of comprehensive spectroscopic analysis and chemical methods. Among these, Calonyctins F–I possessed a skeleton in which the aglycone moiety and the oligosaccharide core were linked by a 3-hydroxy-2-methylbutanoic acid moiety to form a 25-membered macrocyclic structure. Calonyctins E, J, and muricatic acid C methyl ester were non-cytotoxic but enhanced the cytotoxicity of vincristine by 2.5–407.1 fold at 25 μM in KB/VCR cells. Calonyctin E was the most active one.

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Datum: 25.04.2018


Lanostane triterpenes from the mushroom Ganoderma resinaceum and their inhibitory activities against α-glucosidase

Publication date: May 2018
Source:Phytochemistry, Volume 149
Author(s): Xian-Qiang Chen, Jing Zhao, Ling-Xiao Chen, Shen-Fei Wang, Ying Wang, Shao-Ping Li
Eighteen previously undescribed lanostane triterpenes and thirty known analogues were obtained from the fruiting bodies of Ganoderma resinaceum. Resinacein C was isolated from a natural source for the first time. The structures of all the above compounds were elucidated by extensive spectroscopic analysis and comparisons of their spectroscopic data with those reported in the literature. Furthermore, in an in vitro assay, Resinacein C, ganoderic acid Y, lucialdehyde C, 7-oxo-ganoderic acid Z3, 7-oxo-ganoderic acid Z, and lucidadiol showed strong inhibitory effects against α-glucosidase compared with the positive control drug acarbose. The structure-activity relationships of ganoderma triterpenes on α-glucosidase inhibition showed that the C-24/C-25 double bond is necessary for α-glucosidase inhibitory activity. Moreover, the carboxylic acid group at C-26 and the hydroxy group at C-15 play important roles in enhancing inhibitory effects of these triterpenes.

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Datum: 25.04.2018


Editorial Board/Publication Information

Publication date: April 2018
Source:Phytochemistry, Volume 148




Datum: 25.04.2018


Sucrose diester of aryldihydronaphthalene-type lignans from Echium angustifolium Mill. and their antitumor activity

Publication date: May 2018
Source:Phytochemistry, Volume 149
Author(s): Ahmed Ramadan El-Rokh, Amr Negm, Maha El-Shamy, Mohamed El-Gindy, Mamdouh Abdel-Mogib
Four previously undescribed sucrose diester of aryldihydronaphthalene-type lignans, named echiumins A-D, were isolated from the butanol fraction of Echium angustifolium Mill, in addition to a known compound, trigonotin A, which is reported for the first time from the title plant. The structures of isolated compounds were elucidated using spectroscopic methods such as HRESIMS and 1D and 2D NMR spectroscopy. The isolated compounds displayed strong to weak antitumor activity against HepG2 and MCF7 cancer cell lines, with echiumins A and D showed the most potent activity.

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Datum: 25.04.2018


Graphical Contents List

Publication date: May 2018
Source:Phytochemistry, Volume 149




Datum: 25.04.2018


Cytokinin activity of N6-benzyladenine derivatives assayed by interaction with the receptors in planta, in vitro, and in silico

Publication date: May 2018
Source:Phytochemistry, Volume 149
Author(s): Ekaterina M. Savelieva, Vladimir E. Oslovsky, Dmitry S. Karlov, Nikolay N. Kurochkin, Irina A. Getman, Sergey N. Lomin, Georgy V. Sidorov, Sergey N. Mikhailov, Dmitry I. Osolodkin, Georgy A. Romanov
Biological effects of hormones in both plants and animals are based on high-affinity interaction with cognate receptors resulting in their activation. The signal of cytokinins, classical plant hormones, is perceived in Arabidopsis by three homologous membrane receptors: AHK2, AHK3, and CRE1/AHK4. To study the cytokinin–receptor interaction, we used 25 derivatives of potent cytokinin N6-benzyladenine (BA) with substituents in the purine heterocycle and/or in the side chain. The study was focused primarily on individual cytokinin receptors from Arabidopsis. The main in planta assay system was based on Arabidopsis double mutants retaining only one isoform of cytokinin receptors and harboring cytokinin-sensitive reporter gene. Classical cytokinin biotest with Amaranthus seedlings was used as an additional biotest. In parallel, the binding of ligands to individual cytokinin receptors was assessed in the in vitro test system. Quantitative comparison of results of different assays confirmed the partial similarity of ligand-binding properties of receptor isoforms. Substituents at positions 8 and 9 of adenine moiety, elongated linker up to 4 methylene units, and replacement of N6 by sulfur or oxygen have resulted in the suppression of cytokinin activity of the derivative toward all receptors. Introduction of a halogen into position 2 of adenine moiety, on the contrary, often increased the ligand activity, especially toward AHK3. Features both common and distinctive of cytokinin receptors in Arabidopsis and Amaranthus were revealed, highlighting species specificity of the cytokinin perception apparatus. Correlations between the extent to which a compound binds to a receptor in vitro and its ability to activate the same receptor in planta were evaluated for each AHK protein. Interaction patterns between individual receptors and ligands were rationalized by structure analysis and molecular docking in sensory modules of AHK receptors. The best correlation between docking scores and specific binding was observed for AHK3. In addition, receptor-specific ligands have been discovered with unique properties to predominantly activate or block distinct cytokinin receptors. These ligands are promising for practical application and as molecular tools in the study of the cytokinin perception by plant cells.

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Datum: 25.04.2018


Diterpenes from buds of Wikstroemia chamaedaphne showing anti-hepatitis B virus activities

Publication date: July 2018
Source:Phytochemistry, Volume 151
Author(s): Shi-Fei Li, Ying-Ying Jiao, Zhi-Qiang Zhang, Jian-Bin Chao, Jie Jia, Xun-Long Shi, Li-Wei Zhang
Phytochemical study of the buds of Wikstroemia chamaedaphne Meisn. led to the isolation of seven previously undescribed diterpenes, including one tigliane diterpene (wikstchalide A), two daphnane diterpenes (wikstroelides W-X), and four lathyrane diterpenes (laurifoliosides A-B and 2-epi-laurifoliosides A-B), along with four known diterpenes. The structures of these compounds were established by extensive spectroscopic evidence and electronic circular dichroism (ECD) calculations. Wikstchalide A possesses a 5,6-epoxy ring in the tigliane skeleton. Two compounds exhibited potential anti-hepatitis B virus activities, with IC50 values of 46.5 and 88.3 μg/mL against hepatitis B virus (HBV) surface antigen (HBsAg), and six compounds showed certain inhibitory effects on HBV-DNA replication with the inhibition ratios ranging from 2.0% to 33.0% at the concentrations ranging from 0.39 to 6.25 μg/mL.

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Datum: 25.04.2018


Protective effects of total alkaloids from Dendrobium crepidatum against LPS-induced acute lung injury in mice and its chemical components

Publication date: May 2018
Source:Phytochemistry, Volume 149
Author(s): Yang Hu, Jie Ren, Lei Wang, Xin Zhao, Mian Zhang, Kuniyoshi Shimizu, Chaofeng Zhang
Dendrobium crepidatum was one of the sources of Herba Dendrobii, a famous and precious traditional Chinese medicine. Indolizine-type alkaloids are the main characteristic ingredients of D. crepidatum, which possesses a variety of changeable skeletons. In the present study, we found that the total alkaloids of D. crepidatum (TAD) can inhibit the production of nitric oxide (NO) in lipopolysaccharide (LPS)-activated macrophages and showed protective effects against LPS-induced acute lung injury (ALI) in mice through downregulating the TLR4-mediated MyD88/MAPK signaling pathway. Further phytochemical study showed that six previously undescribed indolizine-type compounds, including a racemic mixture (dendrocrepidine A-E) were isolated from TAD. Meanwhile, dendrocrepidine F was separated into a pair of enantiomers by a chiral chromatography, and their absolute configurations were assigned by single-crystal X-ray diffraction analysis. The isomer (−)-dendrocrepidine F showed higher anti-inflammatory effects by inhibiting NO production in LPS-treated macrophages with an IC50 value of 13.3 μM. Taken together, indolizine-type alkaloids are the active components of D. crepidatum through downregulating the TLR4-mediated pathway, indicating some kind of therapy of TAD for ALI treatment.

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Datum: 25.04.2018


Antimicrobial activity and cytotoxicity of xanthoquinodin analogs from the fungus Cytospora eugeniae BCC42696

Publication date: July 2018
Source:Phytochemistry, Volume 151
Author(s): Karoon Sadorn, Siriporn Saepua, Nattawut Boonyuen, Tanapong Boonruangprapa, Pranee Rachtawee, Pattama Pittayakhajonwut
Eleven previously undescribed compounds, including cytosporanthraxanthone, xanthoquinodins A7–A10, ketoxanthoquinodin A6, xanthoquinodins B6–B8, and spiroxanthoquinodins A and B, and one synthetically known compound, 2-methoxy pinselin, as well as ten known compounds, including xanthoquinodins A4−A6, B4, and B5, chrysophanol, physcion, (4S)-5-hydroxy-4-methoxy-α-tetralone, (4S)-4,8-dihydroxy-α-tetralone (or isosclerone), and gonytolide C were isolated from the fungus Cytospora eugeniae BCC42696. Their chemical structures were determined based on the analysis of NMR spectroscopic and mass spectrometric data. Moreover, the absolute configurations of the unknown compounds were established by using NOESY and NOEDIFF NMR experiments along with CD spectroscopic data. The isolated xanthoquinodins exhibited a broad range of antimalarial, antibacterial, and fungicidal activities as well as cytotoxicity. Xanthoquinodins A6, B4, and B5 showed strong activity to Plasmodium falciparum, K1 strain (IC50 0.52–0.92 μM) and displayed anti-Bacillus cereus (MIC 1.56 μg/mL). Xanthoquinodin A6 also showed anti-Curvularia lunata (MIC 3.13 μg/mL). In addition, xanthoquinodins A4, A6, B4, and B5 and ketoxanthoquinodin A6 showed cytotoxicity against both cancerous (MCF-7, KB, NCI-H187) and non-cancerous (Vero) cells.

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Datum: 25.04.2018


Towards a complete characterisation of guaiacwood oil

Publication date: May 2018
Source:Phytochemistry, Volume 149
Author(s): Loïc Tissandié, Stéphane Viciana, Hugues Brevard, Uwe J. Meierhenrich, Jean-Jacques Filippi
Guaiacwood oil is a common perfume ingredient used in modern compositions for its suave woody-rosy scent. This essential oil is a byproduct of the timber industry obtained by hydrodistillation of the heartwood of Bulnesia sarmientoi, a tree native from Latin America. Despite being widely used in perfumery, guaiacwood oil has been poorly described in the past. This study aims at giving an in-depth characterisation of its chemical composition as well as disclosing the odorant compounds responsible for its characteristic fragrance. Our methodology was based on a combination of fractionation and analytical techniques, including comprehensive two-dimensional gas chromatography coupled to mass spectrometry and preparative capillary-gas chromatography. The entire analytical work led to the isolation of 20 constituents among which 14 have never been reported so far in natural extracts. Each isolated compound was fully characterised by spectroscopic methods. Finally, the accurate knowledge of the chemical composition permitted the identification of the odour-active constituents by gas chromatography-olfactometry.

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Datum: 25.04.2018


Bioactive carbazole and quinoline alkaloids from Clausena dunniana

Publication date: July 2018
Source:Phytochemistry, Volume 151
Author(s): Nankai Cao, Yuemei Chen, Xiaoli Ma, Kewu Zeng, Mingbo Zhao, Pengfei Tu, Jun Li, Yong Jiang
Nine undescribed carbazole and quinoline alkaloids, named dunnines A–E, and 14 known analogues were isolated from the leaves and stems of Clausena dunniana. Their structures were elucidated on the basis of comprehensive analysis of NMR and HRMS spectroscopic data, and the absolute configurations were assigned via comparison of their specific rotations and calculated and experimental ECD data. (±)-Dunnines A–C and (±)-clausenawalline A are four pairs of biscarbazole atropisomers and (±)-dunnine D is a pair of dihydropyranocarbazole enantiomers. They were separated by chiral HPLC to obtain the optically pure compounds. Three compounds showed weak inhibitory effects on nitric oxide production stimulated by lipopolysaccharide in BV-2 microglial cells (IC50 > 50 μM); five compounds could significantly promote insulin secretion in HIT-T15 cell line (1.9–3.1-fold of the control, p < 0.01) at 40 μM, and nine compounds could inhibit the apoptosis of PC12 cell induced by 6-hydroxydopamine with IC50 values in the range of 10.9–47.2 μM.

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Datum: 25.04.2018


(P)/(M)-corinepalensin A, a pair of axially chiral prenylated bicoumarin enantiomers with a rare C-5C-5′ linkage from the twigs of Coriaria nepalensis

Publication date: May 2018
Source:Phytochemistry, Volume 149
Author(s): Lin Chen, Gui-Hua Tang, Fu-Liang Guo, Wei Li, Jun-Sheng Zhang, Bo Liu, Sheng Yin
A pair of undescribed bicoumarin enantiomers, (P)/(M)-corinepalensin A, two undescribed prenylated coumarins, corinepalensins B and C, along with ten known coumarins were isolated from the twigs of Coriaria nepalensis. (P)/(M)-corinepalensin A feature a rare C-5C-5′ axially chiral linkage between two prenylated coumarin monomers. Their structures were determined by a combination of spectroscopic methods, single crystal X-ray diffraction, and ECD calculations. All isolates were evaluated for the inhibitory activity against phosphodiesterase-4 (PDE4), which is a drug target for the treatment of asthma and chronic obstructive pulmonary disease. Compounds (P)-corinepalensin A, (M)-corinepalensin A, corinepalensin B, norbraylin, braylin, and nepalin C exhibited significant inhibition with IC50 values ranging from 0.43 to 7.15 μM.

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Datum: 25.04.2018


Use of fatty acids in the chemotaxonomy of the family Selenastraceae (Sphaeropleales, Chlorophyceae)

Publication date: July 2018
Source:Phytochemistry, Volume 151
Author(s): Cilene Cristina Mori, Inessa Lacativa Bagatini, Thais Garcia da Silva, Christopher Charles Parrish, Armando Augusto Henriques Vieira
The family Selenastraceae includes many species of freshwater green microalgae with morphological characteristics that are so subtly different that it is difficult to discriminate species within it. Therefore, the use of the diacritical characteristics of traditional morphological taxonomy may be ineffective at differentiating among many species of the family. Chemotaxonomy based on fatty acid methyl ester (FAME) can help resolve uncertainties not completely addressed by other approaches, such as molecular studies of some species within the Selenastraceae. Here, we first tested three techniques for the analysis of microalgal FAME to choose the one that would provide the best profiles for chemotaxonomy: 1) direct transesterification (DT) of the biomass followed by gas chromatography coupled to mass spectrometry analysis (GC-MS); 2) extraction using chloroform and methanol, followed by transesterification (T) and then analysis by gas chromatography/flame ionization detector (GC-FID); and 3) extraction with chloroform and methanol and then separation into lipid classes using thin-layer chromatography (TLC) using the Iatroscan-Chromarod system. The tests were conducted on 12 strains (11 species) of Selenastraceae and one outgroup strain. The fatty acid profiles produced by the DT-GC-MS technique yielded the best results for the chemotaxonomy of the Selenastraceae species using 12 FAME. The proportion of the variance in the fatty acid profiles obtained with DT-GC-MS analysis explained by species was 85%, whereas the differences explained by strains was 92%. Therefore, DT-GC-MS was used to analyze other microalgae strains, totaling 15 species of 8 genera of green coccoid microalgae, including the recently described Curvastrum. The results with all strains showed that fatty acid profiles obtained by DT-GC-MS were significantly different (p < 0.001) among strains and among species. The variance in fatty acids profiles explained by separation into strains was 97%, whereas the separation into species explained 93% of the variance. Statistical analyses showed that, for our dataset, the C18 fatty acids 18:3ω3 and 18:4ω6 were indicative of the Selenastraceae. Therefore, fatty acid profiles are a useful auxiliary chemotaxonomic tool for species identification in Selenastraceae.

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Datum: 25.04.2018


Outside Front Cover

Publication date: April 2018
Source:Phytochemistry, Volume 148




Datum: 25.04.2018


Seasonality effect on the composition of oxindole alkaloids from distinct organs of Uncaria tomentosa from the Caribbean region of Costa Rica

Publication date: July 2018
Source:Phytochemistry, Volume 151
Author(s): Silvana Alvarenga-Venutolo, Catalina Rosales-López, Luis Sánchez-Chinchilla, Rodrigo Muñoz-Arrieta, Francisco Aguilar-Cascante
Uncaria tomentosa (Willd.) D.C. (Rubiaceae), commonly known as “Uña de Gato” or “Cat's Claw”, is a tropical vine from the rainforest used in traditional medicine and spread through Central and South America, including Costa Rica. There is an increasing demand for medicinal extracts with biological activity attributed mainly to oxindole alkaloids (OA), where the ratio between tetracyclic (TOA) and pentacyclic oxindole alkaloids (POA) determines its feasibility for medicinal applications. The ratio is affected by distinct factors including the dynamics of environmental conditions during seasons. The purpose of the study was to assess the seasonality effect in oxindole alkaloids content in relation to plant organs from U. tomentosa grown in the Caribbean region of Costa Rica. Young leaves followed by mature leaves presented the highest amount of total OA during seasons; for these, isoryncophylline, pteropodine and isomitraphylline, were the predominant OA. The POA/TOA ratio of both leaf materials was nearly 1:1 (3.2 mg g−1: 3.1 mg g−1). Bark and root material showed a pentacyclic chemotype in all seasons with a ratio of 6:1 (6.7 mg g−1: 1.3 mg g−1) with pteropodine and isomitraphylline as the predominant POA. The POA content presented seasonality with a significant increase from rainy to dry season in young leaves, bark and roots. In contrast, TOA amount remained virtually unchanged in all plant parts. Humidity and temperature between the studied seasons were constant except for precipitation, reflecting that differences of water content had an effect in the POA amounts. Further studies of abiotic factors, like water stress, could explain the variation of POA content due to seasonality.

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Datum: 25.04.2018


Outside Front Cover

Publication date: May 2018
Source:Phytochemistry, Volume 149




Datum: 25.04.2018


Biochemical characterization in Norway spruce (Picea abies) of SABATH methyltransferases that methylate phytohormones

Publication date: May 2018
Source:Phytochemistry, Volume 149
Author(s): Minta Chaiprasongsuk, Chi Zhang, Ping Qian, Xinlu Chen, Guanglin Li, Robert N. Trigiano, Hong Guo, Feng Chen
Indole-3-acetic acid (IAA), gibberellins (GAs), salicylic acid (SA) and jasmonic acid (JA) exist in methyl ester forms in plants in addition to their free acid forms. The enzymes that catalyze methylation of these carboxylic acid phytohormones belong to a same protein family, the SABATH methyltransferases. While the genes encoding these enzymes have been isolated from a small number of flowering plants, little is known about their occurrence and evolution in non-flowering plants. Here, we report the systematic characterization of the SABATH family from Norway spruce (Picea abies), a gymnosperm. The Norway spruce genome contains ten SABATH genes (PaSABATH1-10). Full-length cDNA for each of the ten PaSABATH genes was cloned and expressed in Escherichia coli. Recombinant PaSABATHs were tested for activity with IAA, GA, SA, and JA. Among the ten PaSABATHs, five had activity with one or more of the four substrates. PaSABATH1 and PaSABATH2 had the highest activities with IAA and SA, respectively. PaSABATH4, PaSABATH5 and PaSABATH10 all had JA as a preferred substrate but with notable differences in biochemical properties. The structural basis of PaSABATHs in discriminating various phytohormone substrates was inferred based on structural models of the enzyme-substrate complexes. The phylogeny of PaSABATHs with selected SABATHs from other plants implies that the enzymes methylating IAA are conserved in seed plants whereas the enzymes methylating JA and SA have independent evolution in gymnosperms and angiosperms.

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Datum: 25.04.2018


Design, synthesis and perception of fluorescently labeled isoprenoid cytokinins

Publication date: June 2018
Source:Phytochemistry, Volume 150
Author(s): Karolina Kubiasová, Václav Mik, Jaroslav Nisler, Martin Hönig, Alexandra Husičková, Lukáš Spíchal, Zuzana Pěkná, Olga Šamajová, Karel Doležal, Ondřej Plíhal, Eva Benková, Miroslav Strnad, Lucie Plíhalová
Isoprenoid cytokinins play a number of crucial roles in the regulation of plant growth and development. To study cytokinin receptor properties in plants, we designed and prepared fluorescent derivatives of 6-[(3-methylbut-2-en-1-yl)amino]purine (N6-isopentenyladenine, iP) with several fluorescent labels attached to the C2 or N9 atom of the purine moiety via a 2- or 6-carbon linker. The fluorescent labels included dansyl (DS), fluorescein (FC), 7-nitrobenzofurazan (NBD), rhodamine B (RhoB), coumarin (Cou), 7-(diethylamino)coumarin (DEAC) and cyanine 5 dye (Cy5). All prepared compounds were screened for affinity for the Arabidopsis thaliana cytokinin receptor (CRE1/AHK4). Although the attachment of the fluorescent labels to iP via the linkers mostly disrupted binding to the receptor, several fluorescent derivatives interacted well. For this reason, three derivatives, two rhodamine B and one 4-chloro-7-nitrobenzofurazan labeled iP were tested for their interaction with CRE1/AHK4 and Zea mays cytokinin receptors in detail. We further showed that the three derivatives were able to activate transcription of cytokinin response regulator ARR5 in Arabidopsis seedlings. The activity of fluorescently labeled cytokinins was compared with corresponding 6-dimethylaminopurine fluorescently labeled negative controls. Selected rhodamine B C2-labeled compounds 17, 18 and 4-chloro-7-nitrobenzofurazan N9-labeled compound 28 and their respective negative controls (19, 20 and 29, respectively) were used for in planta staining experiments in Arabidopsis thaliana cell suspension culture using live cell confocal microscopy.

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Datum: 25.04.2018


Bioactive norditerpenoids from Cephalotaxus fortunei var. alpina and C. lanceolata

Publication date: July 2018
Source:Phytochemistry, Volume 151
Author(s): Ling Ni, Xiu-Hong Zhong, Xiao-Jiao Chen, Bing-Jie Zhang, Mei-Fen Bao, Xiang-Hai Cai
Twenty-eight naturally occurring Cephalotaxus tropone analogues, including 19 previously undescribed ones, were identified from Cephalotaxus fortunei Hook. var. alpina H. L. Li and C. lanceolata K. M. Feng. The presence of the C20 cephinoids A−E revealed that these tropones were assigned to the norditerpenoids and were perhaps derived from labdane-type diterpenoids. These norditerpenoids showed excellent cytotoxicity against human cancer cells (IC50, 20–0.1 μM) in vitro. The SAR (structure-activity relationship) analysis disclosed that the tropone moiety and the lactone ring were crucial structural features for the observed activities. Further SAR analyses led to a new candidate, cephinoid H, which demonstrated an inhibition of 49.0% by administration to zebrafish at a dose of 60.0 ng/mL, compared to cisplatin (DDP, 22.4%) at 15.0 μg/mL. These compounds might affect the NF-κB signaling pathway rather than binding to microtubules. Additionally, the isolated norditerpenoids showed almost equal anti-inflammatory activities compared to the positive control, MG132.

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Datum: 25.04.2018


Morphology of glandular trichomes of Japanese catnip (Schizonepeta tenuifolia Briquet) and developmental dynamics of their secretory activity

Publication date: June 2018
Source:Phytochemistry, Volume 150
Author(s): Chanchan Liu, Narayanan Srividya, Amber N. Parrish, Wei Yue, Mingqiu Shan, Qinan Wu, B. Markus Lange
Schizonepeta tenuifolia Briquet, commonly known as Japanese catnip, is used for the treatment of colds, headaches, fevers, and skin rashes in traditional Asian medicine (China, Japan and Korea). The volatile oil and its constituents have various demonstrated biological activities, but there is currently limited information regarding the site of biosynthesis. Light microscopy and scanning electron microscopy indicated the presence of three distinct glandular trichome types which, based on their morphological features, are referred to as peltate, capitate and digitiform glandular trichomes. Laser scanning microscopy and 3D reconstruction demonstrated that terpenoid-producing peltate glandular trichomes contain a disk of twelve secretory cells. The oil of peltate glandular trichomes, collected by laser microdissection or using custom-made micropipettes, was demonstrated to contain (−)-pulegone, (+)-menthone and (+)-limonene as major constituents. Digitiform and capitate glandular trichomes did not contain appreciable levels of terpenoid volatiles. The yield of distilled oil from spikes was significantly (44%) higher than that from leaves, while the composition of oils was very similar. Oils collected directly from leaf peltate glandular trichomes over the course of a growing season contained primarily (−)-pulegone (>80% at 32 days after germination) in young plants, while (+)-menthone began to accumulate later (>75% at 80 days after germination), at the expense of (−)-pulegone (the levels of (+)-limonene remained fairly stable at 3–5%). The current study establishes the morphological and chemical characteristics of glandular trichome types of S. tenuifolia, and also provides the basis for unraveling the biosynthesis of essential oil in this popular medicinal plant.

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Datum: 25.04.2018


Transgenic expression of plant-specific insert of potato aspartic proteases (StAP-PSI) confers enhanced resistance to Botrytis cinerea in Arabidopsis thaliana

Publication date: May 2018
Source:Phytochemistry, Volume 149
Author(s): María Eugenia Frey, Sebastián D'Ippolito, Alfonso Pepe, Gustavo Raúl Daleo, María Gabriela Guevara
The plant-specific insert of Solanum tuberosum aspartic proteases (StAP-PSI) has high structural similarity with NK-lysin and granulysin, two saposin-like proteins (SAPLIPs) with antimicrobial activity. Recombinant StAP-PSI and some SAPLIPs show antimicrobial activity against pathogens that affect human and plants. In this work, we transformed Arabidopsis thaliana plants with StAP-PSI encoding sequence with its corresponding signal peptide under the control of the cauliflower mosaic virus (CaMV) 35S promoter. Results obtained show that StAP-PSI significantly enhances Arabidopsis resistance against Botrytis cinerea infection. StAP-PSI is secreted into the leaf apoplast and acts directly against pathogens; thereby complementing plant innate immune responses. Data obtained from real-time PCR assays show that the constitutive expression of StAP-PSI induces the expression of genes that regulate jasmonic acid signalling pathway, such as PDF1.2, in response to infection due to necrotrophic pathogens. On the other hand, according to the data described for other antimicrobial peptides, the presence of the StAP-PSI protein in the apoplast of A. thaliana leaves is responsible for the expression of salicylic acid-associated genes, such as PR-1, irrespective of infection with B. cinerea. These results indicate that the increased resistance demonstrated by A. thaliana plants that constitutively express StAP-PSI owing to B. cinerea infection compared to the wild-type plants is a consequence of two factors, i.e., the antifungal activity of StAP-PSI and the overexpression of A. thaliana defense genes induced by the constitutive expression of StAP-PSI. We suggest that the use of this protein would help in minimizing the ecological and health risks that arise from the use of pesticides.We suggest that the use of this protein would help in minimizing the ecological and health risks that arise from the spreading of resistance of agriculturally important pathogens.

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Datum: 25.04.2018


Discrimination of different geographic varieties of Gymnema sylvestre, an anti-sweet plant used for the treatment of type 2 diabetes

Publication date: June 2018
Source:Phytochemistry, Volume 150
Author(s): Ha Thanh Tung Pham, Minh Chau Hoang, Thi Kim Quy Ha, Lan Huong Dang, Van On Tran, Thi Bich Thu Nguyen, Chul Ho Lee, Won Keun Oh
Gymnema sylvestre (Retz.) R.Br. ex Sm. (Asclepiadaceae) is a well-known Ayurvedic anti-sweet plant for the treatment of type 2 diabetes mellitus. Although it was previously proposed that G. sylvestre exhibits chemical variation based on geography, most research on G. sylvestre has used material originating from India. Morphological and anatomical descriptions, ITS1-5.8S-ITS2 DNA sequencing, and acid hydrolysis analyses showed that G. sylvestre samples from Vietnam are distinguishable from those of Indian origin and thus suggest a dissimilarity among G. sylvestre samples with different geographic distributions. An LC-MS-guided strategy targeting 3β-glucuronide oleane-triterpenes in the Vietnamese G. sylvestre variety led to the isolation of four known compounds and nine previously undescribed compounds, named gymnemosides ND1-ND9. None of the isolated compounds were reported in the Indian sample, further supporting the geo-diversity of G. sylvestre. Three compounds, gymnemosides ND7-9, exerted significant stimulatory effects on the uptake of 2-NBDG in 3T3-L1 adipocyte cells and thus have potential as lead molecules for anti-diabetes agents.

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Datum: 25.04.2018


Ilicicolinic acids and ilicicolinal derivatives from the fungus Neonectria discophora SNB-CN63 isolated from the nest of the termite Nasutitermes corniger found in French Guiana show antimicrobial activity

Publication date: July 2018
Source:Phytochemistry, Volume 151
Author(s): Jonathan Sorres, Abir Sabri, Orianne Brel, Didier Stien, Véronique Eparvier
The fungus Neonectria discophora SNB-CN63 has been isolated from the nest of the termite Nasutitermes corniger found in French Guiana. From the ethyl acetate extract of fungal culture, bioassay guided fractionation led to the isolation of fourteen ilicicolinic acids and ilicicolinal derivatives. Their structures were elucidated by analyses of 1D and 2D NMR and MS spectroscopic data. All metabolites were tested against several microbial pathogens and six displayed antimicrobial activities with MIC <16 μg/mL on T. rubrum, Staphylococcus aureus and methicillin-resistant S. aureus. Based on their structural similarities, a common biosynthetic pathway is proposed for all isolated metabolites.

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Datum: 25.04.2018


Radial distribution of wood extractives in European larch Larix decidua by TOF-SIMS imaging

Publication date: June 2018
Source:Phytochemistry, Volume 150
Author(s): Tingting Fu, Nicolas Elie, Alain Brunelle
Wood extractives in the xylem of European larch Larix decidua were mapped by time-of-flight secondary ion mass spectrometry (TOF-SIMS) imaging, which allows the radial distribution of both mineral and lipophilic extractives in the xylem to be scrutinized with high spatial resolution for the first time. Results show that all the components are inhomogeneously distributed across the annual ring. Mineral nutrients including Na+, K+, Ca+, and Cl ions exhibit no preferential localization between earlywood and latewood, whereas PO3 ion is exclusively present in the ray cells, indicating it may be related to acid phosphatase. Lipophilic extractives were found to be more abundant in the inner secondary xylem. Ion images with 400 nm spatial resolution reveal that fatty acids, triglycerides and phytosterols are co-localized principally in the earlywood within the first annual ring. Resin acids prove to be the main components in the resin canal of the secondary xylem and are distributed in the outer of it.

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Datum: 25.04.2018


Anti-inflammatory flavone and chalcone derivatives from the roots of Pongamia pinnata (L.) Pierre

Publication date: May 2018
Source:Phytochemistry, Volume 149
Author(s): Ran Wen, Hai-Ning Lv, Yong Jiang, Peng-Fei Tu
A phytochemical study on the roots of Pongamia pinnata (L.) Pierre yielded 52 flavonoids, including four previously undescribed flavone and four previously undescribed chalcone derivatives. The structures of the isolated compounds were determined on the basis of the 1D, 2D NMR, and mass spectroscopic data. The absolute configurations of the compounds were assigned via the specific rotation, Mosher's method, as well as the electronic circular dichroism (ECD) spectra. All the isolates were evaluated for their inhibitory effects on NO production in LPS-stimulated BV-2 microglial cells. Ten compounds showed significant inhibitory effects against NO production, comparable to the positive control, dexamethasone.

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Datum: 25.04.2018


Characterization of anthocyanins in the hybrid progenies derived from Iris dichotoma and I. domestica by HPLC-DAD-ESI/MS analysis

Publication date: June 2018
Source:Phytochemistry, Volume 150
Author(s): Wenji Xu, Gangjun Luo, Fengyang Yu, Qingxiang Jia, Yang Zheng, Xiaoying Bi, Jiajun Lei
Iris dichotoma with different flower colors and I. domestica are beardless wild irises belonging to the family Iridaceae that bloom in the summer and have long flowering periods. In this study, we collected three accessions of I. dichotoma with violet, yellow, and white flowers, respectively, in China, and crossed them with I. domestica individuals. The flower color of the hybrids derived from these crosses was categorized into eight groups: violet, purple, brown, orange, red, pink, yellow, and white. From this population, 45 individuals were selected for analysis, and their fully expanded inner and outer perianths were harvested for extraction of anthocyanins. Using high-performance liquid chromatography-mass spectrometry (HPLC-MS) analysis, 29 anthocyanins were identified by comparing MS and UV–visible spectra and elution order based on published data and guidelines. The 29 anthocyanins were classified into six groups: non-acylated glycosides (3RG, 3RG5G), acetylglycosides (3acRG5G), p-coumaroylglycosides (3pCRG, 3pCRG5G), caffeoylglycosides (3CRG5G), feruloylglycosides (3feRG, 3feRG5G), and acetyl-(p-coumaroyl) glycosides (3ac-pCRG5G). Acylated anthocyanin contents were considerably higher than non-acylated anthocyanin contents in the individuals evaluated, regardless of flower color, except in the yellow-flowered I. dichotoma and its yellow-flowered progeny. We found ten anthocyanins derived from pelargonidin, including pelargonidin 3-O-(caffeoyl)rutinoside-5-O-glucoside (Pg3CRG5G), pelargonidin 3-O-(feruloyl)rutinoside-5-O-glucoside (Pg3feRG5G), and pelargonidin 3-O-(feruloyl)rutinoside (Pg3feRG), that have not yet been reported in other Iris species. Moreover, delphinidin 3-O-(feruloyl) rutinoside-5-O-glucoside (Dp3feRG5G), and delphinidin 3-O-(feruloyl)rutinoside (Dp3feRG) were also characterized for the first time in Iris. Two to five major anthocyanins were detected in the petals of the violet and purple groups, whereas those of the brown group contained three to six anthocyanins. Petals of the orange, red, and pink groups contained two to four major anthocyanins. The total variance explained by the first two principal components (PC) in a PC analysis of the intensities of the compound peaks detected in individuals representing the eight color groups was 44.7%. Individuals were classified into 10 types (A-I to A-X) according to their anthocyanidin composition in the flower petals. Knowledge of the types of anthocyanins determining flower petal color will aid comprehensive understanding of flower color characteristics in hybrid progeny and will contribute to the development of breeding Iris cultivars of diverse flower colors.

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Datum: 25.04.2018


Hebecarposides A−K, antiproliferative lanostane-type triterpene glycosides from the leaves of Lyonia ovalifolia var. hebecarpa

Publication date: July 2018
Source:Phytochemistry, Volume 151
Author(s): Yang Teng, Hanqi Zhang, Junfei Zhou, Guanqun Zhan, Guangmin Yao
Eleven previously undescribed lanostane-type triterpene glycosides, hebecarposides A−K, were isolated from the leaves of Lyonia ovalifolia var. hebecarpa (Ericaceae), along with two known analogues, lyonifolosides L and O. The structures of hebecarposides A−K were established by extensive spectroscopic analysis and chemical methods, and the absolute configuration of C-24 in hebecarposides A and E was determined to be S and R, respectively, by a Mo2(OAc)4−induced electronic circular dichroism method. This is the first report of the presence of lanostane-type triterpene glycosides in L. ovalifolia var. hebecarpa. All compounds were evaluated for their antiproliferative activities against five cancer cell lines, SMMC-7721, HL-60, SW480, MCF-7, and A-549, and a normal epithelial cell line BEAS-2B, and none of them showed general cytotoxity to the normal cell line BEAS-2B. Interestingly, hebecarposides C, D, G, and K selectively inhibited the proliferation of HL-60 and SMMC-7721 cell lines, and hebecarposides C and D showed significant anti-proliferative activities against A-549 cell lines than the positive control, cis-platin. In addition, hebecarposides C and H exhibited more potent anti-proliferative activities against MCF-7 than cis-platin.

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Datum: 25.04.2018


Metabolomic analysis applied to chemosystematics and evolution of megadiverse Brazilian Vernonieae (Asteraceae)

Publication date: June 2018
Source:Phytochemistry, Volume 150
Author(s): Marília Elias Gallon, Marcelo Monge, Rosana Casoti, Fernando Batista Da Costa, João Semir, Leonardo Gobbo-Neto
Vernonia sensu lato is the largest and most complex genus of the tribe Vernonieae (Asteraceae). The tribe is chemically characterized by the presence of sesquiterpene lactones and flavonoids. Over the years, several taxonomic classifications have been proposed for Vernonia s.l. and for the tribe; however, there has been no consensus among the researches. According to traditional classification, Vernonia s.l. comprises more than 1000 species divided into sections, subsections and series (sensu Bentham). In a more recent classification, these species have been segregated into other genera and some subtribes were proposed, while the genus Vernonia sensu stricto was restricted to 22 species distributed mainly in North America (sensu Robinson). In this study, species from the subtribes Vernoniinae, Lepidaploinae and Rolandrinae were analyzed by UHPLC-UV-HRMS followed by multivariate statistical analysis. Data mining was performed using unsupervised (HCA and PCA) and supervised methods (OPLS-DA). The HCA showed the segregation of the species into four main groups. Comparing the HCA with taxonomical classifications of Vernonieae, we observed that the groups of the dendogram, based on metabolic profiling, were in accordance with the generic classification proposed by Robinson and with previous phylogenetic studies. The species of the genera Stenocephalum, Stilpnopappus, Strophopappus and Rolandra (Group 1) were revealed to be more related to the species of the genus Vernonanthura (Group 2), while the genera Cyrtocymura, Chrysolaena and Echinocoryne (Group 3) were chemically more similar to the genera Lessingianthus and Lepidaploa (Group 4). These findings indicated that the subtribes Vernoniinae and Lepidaploinae are non-chemically homogeneous groups and highlighted the application of untargeted metabolomic tools for taxonomy and as indicators of species evolution. Discriminant compounds for the groups obtained by OPLS-DA were determined. Groups 1 and 2 were characterized by the presence of 3′,4′-dimethoxyluteolin, glaucolide A and 8-tigloyloxyglaucolide A. The species of Groups 3 and 4 were characterized by the presence of putative acacetin 7-O-rutinoside and glaucolide B. Therefore, untargeted metabolomic approach combined with multivariate statistical analysis, as proposed herein, allowed the identification of potential chemotaxonomic markers, helping in the taxonomic classifications.

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Datum: 25.04.2018


Alkaloids with neuroprotective effects from the leaves of Isatis indigotica collected in the Anhui Province, China

Publication date: May 2018
Source:Phytochemistry, Volume 149
Author(s): Si-Fan Liu, Ying-Ying Zhang, Le Zhou, Bin Lin, Xiao-Xiao Huang, Xiao-Bo Wang, Shao-Jiang Song
Six undescribed alkaloids, indiforine A-F, together with four known ones, were isolated from the leaves of Isatis indigotica Fortune. Their structures were elucidated on the basis of extensive spectroscopic analyses. The absolute configurations of indiforine A and B were determined by comparison of the experimental and calculated electronic circular dichroism spectra, as well as experimental and calculated optical rotations. The isolated alkaloids were evaluated for their neuroprotective activities against H2O2-induced cell injury in human neuroblastoma SH-SY5Y cells. The results showed that in H2O2-induced SH-SY5Y cell injury models, indiforine A and B exhibited potent neuroprotective activities. Further investigation of the most potent indiforine A by Hoechst 33258 staining and Annexin V/PI analysis demonstrated that it could protect SH-SY5Y cells from oxidative damage through inhibiting cell apoptosis.

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Datum: 25.04.2018


Triterpenoid saponins from Scabiosa stellata collected in North-eastern Algeria

Publication date: June 2018
Source:Phytochemistry, Volume 150
Author(s): Meryem Lehbili, Abdulmagid Alabdul Magid, Ahmed Kabouche, Laurence Voutquenne-Nazabadioko, Hamid Morjani, Dominique Harakat, Zahia Kabouche
Eight undescribed triterpenoid saponins, scabiostellatosides A-H, together with three known compounds were isolated from the whole plant of Scabiosa stellata L. Their structures were established by spectroscopic analyses (1D, 2D-NMR and HRESIMS) and chemical methods. Scabiostellatosides A-H were evaluated for their cytotoxicity against human fibrosarcoma cell line (HT1080). Scabiostellatoside F, a heptasaccharide derivative of oleanolic acid, exhibited moderate cytotoxicity against HT1080 cell line with IC50 value of 12.0 μM.

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Datum: 25.04.2018


Coriariin M, a trimeric hydrolysable tannin with dehydrodigalloyl and valoneoyl groups as linking units, and accompanying dimeric hydrolysable tannins from Coriaria japonica

Publication date: July 2018
Source:Phytochemistry, Volume 151
Author(s): Yuuki Shimozu, Takayasu Hirai, Tsutomu Hatano
Three oligomeric hydrolysable tannins, coriariins K, L, and M, which were previously undescribed, together with five known hydrolysable tannins were isolated from dried leaves of Coriaria japonica. Their structures were determined based on 1D and 2D NMR spectroscopy, HR-ESI-MS, and ECD spectroscopy experiments. Among the isolated compounds, coriariin M has a unique trimer structure where both dehydrodigalloyl and valoneoyl group linkages were found between the hydrolysable tannin monomers. Dimeric hydrolysable tannins coriariins K and L, having a dehydrodigalloyl group as the linking unit, were structurally related to coriariin A, the main hydrolysable tannin of this plant species. Additionally, the complexation of the eight hydrolysable tannins isolated in this study with bovine serum albumin (BSA) to form water-soluble macromolecules was analyzed using native polyacrylamide gel electrophoresis (PAGE). A comparison of the behaviors of the oligomeric hydrolysable tannins suggested the participation of the hexahydroxydiphenoyl group and the importance of the molecular sizes of the hydrolysable tannins in the formation of macromolecules.

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Datum: 25.04.2018


Dinardokanshones C–E, isonardoeudesmols A–D and nardoeudesmol D from Nardostachys jatamansi DC.

Publication date: June 2018
Source:Phytochemistry, Volume 150
Author(s): Hong-Hua Wu, Xu Deng, Hu Zhang, Ying-Peng Chen, Shu-Song Ying, Yi-Jing Wu, Yan-Ting Liu, Yan Zhu, Xiu-Mei Gao, Yan-Tong Xu, Li Li
Dinardokanshones C–E, three sesquiterpenoid dimers comprising an unusual nornardosinane-type sesquiterpenoid core and an aristolane-type sesquiterpenoid unit conjugated by an extra pyran or furan ring, together with monomeric sesquiterpenoids isonardoeudesmols A–D and nardoeudesmol D, were isolated from the underground parts of Nardostachys jatamansi DC. Structures of the eight compounds were elucidated by analysis of the extensive spectroscopic data, and their absolute configurations were established by analysis of NOESY and X-ray diffraction data, combined with computational electronic circular dichroism (ECD) calculations. The results of SERT activity assay revealed that isonardoeudesmol D and nardoeudesmol D significantly inhibited SERT activity, while dinardokanshones D–E and isonardoeudesmols B–C significantly enhanced SERT activity, among which dinardokanshone D exhibited the strongest effect.

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Datum: 25.04.2018


Filler Advert

Publication date: May 2018
Source:Phytochemistry, Volume 149




Datum: 25.04.2018


Aestivalosides A–L, twelve pregnane glycosides from the seeds of Adonis aestivalis

Publication date: June 2018
Source:Phytochemistry, Volume 150
Author(s): Minpei Kuroda, Satoshi Kubo, Daichi Masatani, Yukiko Matsuo, Hiroshi Sakagami, Yoshihiro Mimaki
Eight adonilide (14,20α-epoxy-3β,20-dihydroxy-14β-pregn-5-en-18-oic acid γ-lactone) glycosides, named aestivalosides A–H, and four glycosides of the adonilide derivatives, named aestivalosides I–L, were isolated from the MeOH extract of seeds of Adonis aestivalis. Aestivalosides A–L were previously undescribed compounds, and were structurally characterized using spectroscopic techniques, including two-dimensional NMR, and chemical methods.

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Datum: 25.04.2018


Biotransformation of cyclocanthogenol by the endophytic fungus Alternaria eureka 1E1BL1

Publication date: July 2018
Source:Phytochemistry, Volume 151
Author(s): Güner Ekiz, Seda Duman, Erdal Bedir
The microbial transformation of cyclocanthogenol (CCG), Astragalus sp. originated sapogenin, by the endophytic fungus Alternaria eureka 1E1BL1 isolated from Astragalus angustifolius was investigated. Hydroxylation, oxidation, epoxidation, O-methylation, ring-expansion and methyl migration reactions were observed on the triterpenoid skeleton. As a result, eight metabolites were isolated and the structures of the previously undescribed compounds were established by 1-D, 2-D NMR and HR-MS analyses.

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Datum: 25.04.2018


Alkaloids from Corydalis decumbens suppress neuronal excitability in primary cultures of mouse neocortical neurons

Publication date: June 2018
Source:Phytochemistry, Volume 150
Author(s): Qilong Huang, Juan Chen, Wanjin Zhang, Baoping Zhou, Chunlei Zhang, William H. Gerwick, Zhengyu Cao
Eight previously undescribed alkaloids, named corydemine, dihydrocorydemine, corydedine, 8,13-dioxo-14-hydroxytetrahydropalmatine, egenine-α-N-oxide, egenine-β-N-oxide, 7′-O-ethylegenine-α-N-oxide, and 7′-O-ethylegenine-β-N-oxide, together with three known ones, muramine, l-tetrahydropalmatine, and (+)-egenine, were isolated from the bulbs of Corydalis decumbens. Their structures were elucidated by comprehensive spectroscopic analysis and chemical correlation. The isolated compounds were tested for their ability to modulate neuronal excitability in primary cultured neocortical neurons. Four of the compounds, corydemine, dihydrocorydemine, muramine, and l-tetrahydropalmatine, inhibited neuronal excitability with IC50 values of 3.6, 16.7, 13.5 and 14.0 μM, respectively.

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Datum: 25.04.2018


Biochemical properties of a bacterially-expressed Bowman-Birk inhibitor from Rhynchosia sublobata (Schumach.) Meikle seeds and its activity against gut proteases of Achaea janata

Publication date: July 2018
Source:Phytochemistry, Volume 151
Author(s): Soundappan S. Mohanraj, Sarada D. Tetali, Nalini Mallikarjuna, Aparna Dutta-Gupta, Kollipara Padmasree
Crude proteinase inhibitors (CPIs) extracted from the seeds of Rhynchosia sublobata, a wild relative of pigeon pea showed pronounced inhibitory activity on the larval gut trypsin-like proteases of lepidopteran insect pest – Achaea janata. Consequently, a full-length cDNA of Bowman-Birk inhibitor gene (RsBBI1) was cloned from the immature seeds of R. sublobata. It contained an ORF of 360 bp encoding a 119-amino acid polypeptide (13.3 kDa) chain with an N-terminus signal sequence comprising of 22 amino acids. The amino acid sequence and phylogenetic analysis together revealed that RsBBI1 exhibited a close relation with BBIs from soybean and Phaseolus spp. A cDNA sequence corresponding to RsBBI1 mature protein (89 amino acid stretch) was expressed in E. coli. The recombinant rRsBBI1 protein with a molecular mass of 9.97 kDa was purified using trypsin affinity chromatography. The purified rRsBBI1 exhibited non-competitive mode of inhibition of both bovine trypsin (Ki of 358 ± 11 nM) and chymotrypsin (Ki of 446 ± 9 nM). Its inhibitory activity against these proteases was stable at high temperatures (>95 °C) and a wide pH range but sensitive to reduction with dithiothreitol (DTT), indicating the importance of disulphide bridges in exhibiting its activity. Also, rRsBBI1 showed significant inhibitory activity (IC50 = 70 ng) on A. janata larval gut trypsin-like proteases (AjGPs). Conversely, it showed <1% inhibitory activity (IC50 = 8 μg) on H. armigera larval gut trypsin-like proteases (HaGPs) than it has against AjGPs. Besides, in vivo feeding experiments clearly indicated the deleterious effects of rRsBBI1 on larval growth and development in A. janata which suggests it can be further exploited for such properties.

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Datum: 25.04.2018


Variability between organs of proanthocyanidins in Geranium sylvaticum analyzed by off-line 2-dimensional HPLC-MS

Publication date: June 2018
Source:Phytochemistry, Volume 150
Author(s): Anu Tuominen, Maarit Karonen
Proanthocyanidins have been characterized in the different organs of Geranium sylvaticum by using an off-line 2-dimensional chromatographic method. In the first dimension, proanthocyanidins were separated according to their increasing degree of polymerization by hydrophilic interaction liquid chromatography. In the second dimension, reversed-phase liquid chromatography was used to separate the same size isomers based on their hydrophobicity. Ultraviolet detection and high-resolution electrospray ionization time-of-flight mass spectrometry were used for the identification and characterization of proanthocyanidins. The method was proven to be suitable for the analysis of plant organ fractions of G. sylvaticum that contained complex mixtures of phenolic compounds and proanthocyanidins from several classes. Procyanidins, prodelphinidins and mixed proanthocyanidins composed of both (epi)catechin and (epi)gallocatechin units including monomers, oligomers and polymers up to the degree of polymerization of 20 were identified. The type and size of proanthocyanidins varied between eight studied organs of G. sylvaticum. The 2-dimensional analysis revealed that each proanthocyanidin type occur in the equally complex isomeric pattern. The mean degree of polymerization of different proanthocyanidins in the eight plant organs of G. sylvaticum was 5 and it varied only slightly between plant organs.

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Datum: 25.04.2018


Pentacyclic triterpenoids from Cyclocarya paliurus and their antioxidant activities in FFA-induced HepG2 steatosis cells

Publication date: July 2018
Source:Phytochemistry, Volume 151
Author(s): Hui-Min Yang, Zhi-Qi Yin, Meng-Ge Zhao, Cui-Hua Jiang, Jian Zhang, Ke Pan
Six undescribed pentacyclic triterpenoids including four triterpenoid aglycones, 1β,2a,3β,23-tetrahydroxyurs-12-en-28-ursolic acid, 2a,3a,6β,19α,23-pentahydroxyurs-12-en-28-ursolic acid, 2α,3α,20β,23-tetrahydroxyurs-12-en-28-ursolic acid and 1β,2a,3β,23-tetrahydroxyurs-12,20(30)-dien-28-ursolic acid, and two triterpenoid glucosides, 2a,3a,23-trihydroxy-12,20(30)-dien-28-ursolic acid 28-O-β-d-glucopyranoside and 1-oxo-3β,23-dihydroxyolean-12-en-28-oic acid 28-O-β-d-xylopyranoside, along with 5 known triterpenoids were isolated from a CH3Cl-soluble extract of the leaves of Cyclocarya paliurus. Their structures were established on the basis of chemical and spectroscopic approaches. These compounds were assessed for their antioxidant effects on FFA-induced hepatic steatosis in HepG2 cells. The results revealed that three saponins and two aglycones markedly increased SOD activity and reduced MDA level.

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Datum: 25.04.2018


Biotransformation of ruscogenins by Cunninghamella blakesleeana NRRL 1369 and neoruscogenin by endophytic fungus Neosartorya hiratsukae

Publication date: August 2018
Source:Phytochemistry, Volume 152
Author(s): Özge Özçinar, Özgür Tağ, Hasan Yusufoglu, Bijen Kivçak, Erdal Bedir
Biotransformation of steroidal ruscogenins (neoruscogenin and ruscogenin) was carried out with Cunninghamella blakesleeana NRRL 1369 and endophytic fungus Neosartorya hiratsukae yielding mainly P450 monooxygenase products together with a glycosylated compound. Fermentation of ruscogenins (75:25, neoruscogenin-ruscogenin mixture) with C. blakesleeana yielded 8 previously undescribed hydroxylated compounds. Furthermore, microbial transformation of neoruscogenin by endophytic fungus N. hiratsukae afforded three previously undescribed neoruscogenin derivatives. While hydroxylation at C-7, C-12, C-14, C-21 with further oxidation at C-1 and C-7 were observed with C. blakesleeana, N. hiratsukae biotransformation provided C-7 and C-12 hydroxylated compounds along with C-12 oxidized and C-1(O) glycosylated derivatives. The structures of the metabolites were elucidated by 1-D (1H, 13C and DEPT135) and 2-D NMR (COSY, HMBC, HMQC, NOESY, ROESY) as well as HR-MS analyses.

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Datum: 25.04.2018


Tyrosine biosynthesis, metabolism, and catabolism in plants

Publication date: May 2018
Source:Phytochemistry, Volume 149
Author(s): Craig A. Schenck, Hiroshi A. Maeda
L-Tyrosine (Tyr) is an aromatic amino acid (AAA) required for protein synthesis in all organisms, but synthesized de novo only in plants and microorganisms. In plants, Tyr also serves as a precursor of numerous specialized metabolites that have diverse physiological roles as electron carriers, antioxidants, attractants, and defense compounds. Some of these Tyr-derived plant natural products are also used in human medicine and nutrition (e.g. morphine and vitamin E). While the Tyr biosynthesis and catabolic pathways have been extensively studied in microbes and animals, respectively, those of plants have received much less attention until recently. Accumulating evidence suggest that the Tyr biosynthetic pathways differ between microbes and plants and even within the plant kingdom, likely to support the production of lineage-specific plant specialized metabolites derived from Tyr. The interspecies variations of plant Tyr pathway enzymes can now be used to enhance the production of Tyr and Tyr-derived compounds in plants and other synthetic biology platforms.

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Datum: 25.04.2018


 


Category: Current Chemistry Research

Last update: 28.03.2018.






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