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.

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

 - Phytochemical Analysis.

 - Phytochemistry Letters.

 - Phytochemistry Reviews.



Phytochemistry - Abstracts



Eremophilane sesquiterpenes from Hawaiian endophytic fungus Chaetoconis sp. FT087

Publication date: June 2016
Source:Phytochemistry, Volume 126

Author(s): Chun-Shun Li, Yuanqing Ding, Bao-Jun Yang, Naomi Hoffman, Hong-Quan Yin, Taifo Mahmud, James Turkson, Shugeng Cao

Seven sesquiterpene derivatives, including chaetopenoids A–F and dendryphiellin A1, and 6-methyl-(2E, 4E, 6S) octadienoic acid were isolated from the culture broth of Chaetoconis sp. FT087. Their structures were determined through the analysis of HRMS and NMR spectroscopic data. The absolute configurations of chaetopenoids A–D were elucidated by comparison of their CD and optical rotation data with those in the literature. Chaetopenoids A–C and E belong to the eremophilane type of sesquiterpenoids, while chaetopenoids D and F and dendryphiellin A1 have a trinor-eremophilane skeleton. All compounds were tested against A2780 and cisplatin resistant A2780CisR cell lines, and dendryphiellin A1 was moderately active with IC50 values of 6.6 and 9.1μg/mL, respectively.

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Datum: 05.05.2016


Variability in the carbon isotope composition of individual amino acids in plant proteins from different sources: 1 Leaves

Publication date: May 2016
Source:Phytochemistry, Volume 125

Author(s): Anthony H. Lynch, Nicholas J. Kruger, Robert E.M. Hedges, James S.O. McCullagh

The natural carbon isotope composition of individual amino acids from plant leaf proteins has been measured to establish potential sources of variability. The plant leaves studied, taken from a range of plant groups (forbs, trees, grasses, and freshwater aquatic plants), showed no significant influence of either season or environment (water and light availability) on their Δδ13C values. Plant groups did, however, differ in carbon isotope composition, although no consistent differences were identified at the species level. A discriminant analysis model was constructed which allowed leaves from (1) nettles, (2) Pooideae, (3) other Poales, (4) trees and (5) freshwater higher plants to be distinguished from each other on the basis of their natural abundance 13C/12C ratios of individual amino acids. Differences in carbon isotope composition are known to be retained, to some extent, in the tissues of their consumers, and hence an understanding of compound-specific variation in 13C/12C fractional abundance in plants has the potential to provide dietary insights of value in archaeological and ecological studies.

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Datum: 05.05.2016


Prenylated phenyl polyketides and acylphloroglucinols from Hypericum peplidifolium

Publication date: April 2016
Source:Phytochemistry, Volume 124

Author(s): Serge Alain Tanemossu Fobofou, Chelsea Rebecca Harmon, Antoine Honoré Nkuete Lonfouo, Katrin Franke, Stephen M. Wright, Ludger A. Wessjohann

In search for new or chemo-taxonomically relevant bioactive compounds from chemically unexplored Hypericum species, four previously undescribed natural products, named peplidiforones A–D were isolated and characterized from Hypericum peplidifolium A. Rich., together with six known compounds. The structures of all compounds were elucidated by extensive 1D- and 2D-NMR experiments, high resolution mass spectrometric analyses (HR-MS), and by comparison with data reported in the literature. Seven of these compounds are phenyl polyketides while three are acylphloroglucinol type compounds. Peplidiforone C, which possesses an unusual carbon skeleton consisting of a furan ring substituted by a 2,2-dimethylbut-3-enoyl moiety, is the first example of a prenylated furan derivative isolated from the genus Hypericum. The cytotoxicity, antifungal, and anti-herpes simplex virus type 1 (HSV-1) activities of extracts and compounds are described.

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Datum: 05.05.2016


Editorial Board/Publication Information

Publication date: May 2016
Source:Phytochemistry, Volume 125










Datum: 05.05.2016


Graphical Contents List

Publication date: July 2016
Source:Phytochemistry, Volume 127










Datum: 05.05.2016


Quorum sensing inhibitory potential and molecular docking studies of sesquiterpene lactones from Vernonia blumeoides

Publication date: June 2016
Source:Phytochemistry, Volume 126

Author(s): Abubakar Babando Aliyu, Neil Anthony Koorbanally, Brenda Moodley, Parvesh Singh, Hafizah Yousuf Chenia

The increasing incidence of multidrug-resistant Gram-negative bacterial pathogens has focused research on the suppression of bacterial virulence via quorum sensing inhibition strategies, rather than the conventional antimicrobial approach. The anti-virulence potential of eudesmanolide sesquiterpene lactones previously isolated from Vernonia blumeoides was assessed by inhibition of quorum sensing and in silico molecular docking. Inhibition of quorum sensing-controlled violacein production in Chromobacterium violaceum was quantified using violacein inhibition assays. Qualitative modulation of quorum sensing activity and signal synthesis was investigated using agar diffusion double ring assays and C. violaceum and Agrobacterium tumefaciens biosensor systems. Inhibition of violacein production was concentration-dependent, with ⩾90% inhibition being obtained with ⩾2.4mgml−1 of crude extracts. Violacein inhibition was significant for the ethyl acetate extract with decreasing inhibition being observed with dichloromethane, hexane and methanol extracts. Violacein inhibition ⩾80% was obtained with 0.071mgml−1 of blumeoidolide B in comparison with ⩾3.6mgml−1 of blumeoidolide A. Agar diffusion double ring assays indicated that only the activity of the LuxI synthase homologue, CviI, was modulated by blumeoidolides A and B, and V. blumeoides crude extracts, suggesting that quorum sensing signal synthesis was down-regulated or competitively inhibited. Finally, molecular docking was conducted to explore the binding conformations of sesquiterpene lactones into the binding sites of quorum sensing regulator proteins, CviR and CviR′. The computed binding energy data suggested that the blumeoidolides have a tendency to inhibit both CviR and CviR′ with varying binding affinities. Vernonia eudesmanolide sesquiterpene lactones have the potential to be novel therapeutic agents, which might be important in reducing virulence and pathogenicity of drug-resistant bacteria in vivo.

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Datum: 05.05.2016


Identification and characterization of two bisabolene synthases from linear glandular trichomes of sunflower (Helianthus annuus L., Asteraceae)

Publication date: April 2016
Source:Phytochemistry, Volume 124

Author(s): Anna-Katharina Aschenbrenner, Moonhyuk Kwon, Jürgen Conrad, Dae-Kyun Ro, Otmar Spring

Sunflower is known to produce a variety of bisabolene-type sesquiterpenes and accumulates these substances in trichomes of leaves, stems and flowering parts. A bioinformatics approach was used to identify the enzyme responsible for the initial step in the biosynthesis of these compounds from its precursor farnesyl pyrophosphate. Based on sequence similarity with a known bisabolene synthases from Arabidopsis thaliana AtTPS12, candidate genes of Helianthus were searched in EST-database and used to design specific primers. PCR experiments identified two candidates in the RNA pool of linear glandular trichomes of sunflower. Their sequences contained the typical motifs of sesquiterpene synthases and their expression in yeast functionally characterized them as bisabolene synthases. Spectroscopic analysis identified the stereochemistry of the product of both enzymes as (Z)-γ-bisabolene. The origin of the two sunflower bisabolene synthase genes from the transcripts of linear trichomes indicates that they may be involved in the synthesis of sesquiterpenes produced in these trichomes. Comparison of the amino acid sequences of the sunflower bisabolene synthases showed high similarity with sesquiterpene synthases from other Asteracean species and indicated putative evolutionary origin from a β-farnesene synthase.

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Datum: 05.05.2016


Acetophenone derivatives from a freshwater fungal isolate of recently described Lindgomyces madisonensis (G416)

Publication date: June 2016
Source:Phytochemistry, Volume 126

Author(s): Noemi D. Paguigan, Huzefa A. Raja, Cynthia S. Day, Nicholas H. Oberlies

The exploration of freshwater ascomycetes, which have undergone only limited investigation, may provide opportunities both to characterize new genera/species of fungi and to uncover new chemical diversity. In this study, seven acetophenone derivatives, madisone, 4′-methoxymadisone, dehydromadisone, 2″-methoxymadisone, dihydroallovisnaginone, dimadisone, and 4′-methoxydimadisone were characterized from an organic extract of a recently described Lindgomyces madisonensis (G416) culture, which was isolated from submerged wood collected in a stream in North Carolina. Madisone, dehydromadisone, 2″-methoxymadisone, dimadisone and 4′-demethoxydimadisone have not been reported previously, while 4′-methoxymadisone and dihydroallovisnaginone were previously unknown as natural products. Their structures were assigned on the basis of NMR and HRESIMS data, with the structure of madisone supported by X-ray crystallography. The antimicrobial activities of madisone, 4′-methoxymadisone and dihydroallovisnaginone were evaluated against a panel of bacteria and fungi. A heat map analysis of the surface of a G416 culture showed that most of the isolated compounds concentrated in the guttate compared with the vegetative mycelium of the fungus.

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Datum: 05.05.2016


A Solanum torvum GH3 β-glucosidase expressed in Pichia pastoris catalyzes the hydrolysis of furostanol glycoside

Publication date: July 2016
Source:Phytochemistry, Volume 127

Author(s): Rungarun Suthangkornkul, Pornpisut Sriworanun, Hiroyuki Nakai, Masayuki Okuyama, Jisnuson Svasti, Atsuo Kimura, Saengchan Senapin, Dumrongkiet Arthan

Plant β-glucosidases are usually members of the glucosyl hydrolase 1 (GH1) or 3 (GH3) families. Previously, a β-glucosidase (torvosidase) was purified from Solanum torvum leaves that specifically catalyzed hydrolysis of two furostanol 26-O-β-glucosides, torvosides A and H. Furostanol glycoside 26-O-β-glucosides have been reported as natural substrates of some plant GH1 enzymes. However, torvosidase was classified as a GH3 β-glucosidase, but could not hydrolyze β-oligoglucosides, the natural substrates of GH3 enzymes. Here, the full-length cDNA encoding S. torvum β-glucosidase (SBgl3) was isolated by the rapid amplification of cDNA ends method. The 1887bp ORF encoded 629 amino acids and showed high homology to other plant GH3 β-glucosidases. Internal peptide sequences of purified native Sbgl3 determined by LC–MS/MS matched the deduced amino acid sequence of the Sbgl3 cDNA, suggesting that it encoded the natural enzyme. Recombinant SBgl3 with a polyhistidine tag (SBgl3His) was successfully expressed in Pichia pastoris. The purified SBgl3His showed the same substrate specificity as natural SBgl3, hydrolyzing torvoside A with much higher catalytic efficiency than other substrates. It also had similar biochemical properties and kinetic parameters to the natural enzyme, with slight differences, possibly attributable to post-translational glycosylation. Quantitative real-time PCR (qRT-PCR) showed that SBgl3 was highly expressed in leaves and germinated seeds, suggesting a role in leaf and seedling development. To our knowledge, a recombinant GH3 β-glucosidase that hydrolyzes furostanol 26-O-β-glucosides, has not been previously reported in contrast to substrates of GH1 enzymes.

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Datum: 05.05.2016


Tetrandrine – A molecule of wide bioactivity

Publication date: May 2016
Source:Phytochemistry, Volume 125

Author(s): N. Bhagya, K.R. Chandrashekar

Stephania tetrandra and other related species of Menispermaceae form the major source of the bisbenzylisoquinoline alkaloid – tetrandrine. The plant is extensively referenced in the Chinese Pharmacopoeia for its use in the Chinese medicinal system as an analgesic and diuretic agent and also in the treatment of hypertension and various other ailments, including asthma, tuberculosis, dysentery, hyperglycemia, malaria, cancer and fever. Tetrandrine, well-known to act as a calcium channel blocker, has been tested in clinical trials and found effective against silicosis, hypertension, inflammation and lung cancer without any toxicity. Recently, the efficacy of tetrandrine was tested against Mycobaterium tuberculosis, Candida albicans, Plasmodium falciparum and Ebola virus. Tetrandrine’s pharmacological property has been proved to be through its action on different signalling pathways like reactive oxygen species, enhanced autophagic flux, reversal of multi drug resistance, caspase pathway, cell cycle arrest and by modification of calcium channels. The present review summarises current knowledge on the synthesis, distribution, extraction, structural elucidation, pharmacological properties and the mechanism of action of tetrandrine. Future perspectives in the clinical use of tetrandrine as a drug are also considered.

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Datum: 05.05.2016


Toxin distribution and sphingoid base imbalances in Fusarium verticillioides-infected and fumonisin B1-watered maize seedlings

Publication date: May 2016
Source:Phytochemistry, Volume 125

Author(s): Silvina L. Arias, Verónica S. Mary, Santiago N. Otaiza, Daniel A. Wunderlin, Héctor R. Rubinstein, Martín G. Theumer

Fusarium verticillioides is a major maize pathogen and there are susceptible and resistant cultivars to this fungal infection. Recent studies suggest that its main mycotoxin fumonisin B1 (FB1) may be involved in phytopathogenicity, but the underlying mechanisms are mostly still unknown. This work was aimed at assessing whether FB1 disseminates inside the plants, as well as identifying possible correlations between the maize resistant/susceptible phenotype and the unbalances of the FB1-structurally-related sphingoid base sphinganine (Sa) and phytosphingosine (Pso) due to toxin accumulation. Resistant (RH) and susceptible hybrid (SH) maize seedlings grown from seeds inoculated with a FB1-producer F. verticillioides and from uninoculated ones irrigated with FB1 (20ppm), were harvested at 7, 14 and 21days after planting (dap), and the FB1, Sa and Pso levels were quantified in roots and aerial parts. The toxin was detected in roots and aerial parts for inoculated and FB1-irrigated plants of both hybrids. However, FB1 levels were overall higher in SH seedlings regardless of the treatment (infection or watering). Sa levels increased substantially in RH lines, peaking at 54-fold in infected roots at 14dap. In contrast, the main change observed in SH seedlings was an increase of Pso in infected roots at 7dap. Here, it was found that FB1 disseminates inside seedlings in the absence of FB1-producer fungal infections, perhaps indicating this might condition the fungus–plant interaction before the first contact. Furthermore, the results strongly suggest the existence of at least two ceramide synthase isoforms in maize with different substrate specificities, whose differential expression after FB1 exposure could be closely related to the susceptibility/resistance to F. verticillioides.

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Datum: 05.05.2016


Cytotoxic sesquiterpenoids from Ligularia pleurocaulis

Publication date: May 2016
Source:Phytochemistry, Volume 125

Author(s): Guang-Bo Xie, Ya Xie, Yang-Zhirong Hu, Zhi-Xiang Zhu

The phytochemical investigation of whole plants of Ligularia pleurocaulis led to isolation of five sesquiterpenoids, including an eremophilenolide dimer named biligupleurolide, along with eight known sesquiterpenoids. Their structures were determined by spectroscopic methods including 2D NMR techniques, and the structures of biligupleurolide and ligupleurolide were confirmed by X-ray diffraction analysis. All of the isolated compounds were tested for their cytotoxic activity against three cancer cell lines (HepG2, A549 and MCF-7), and biligupleurolide showed moderate inhibitory activities, with IC50 values of 5.2, 5.6 and 8.4μM against MCF-7, HepG2 and A549, respectively.

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Datum: 05.05.2016


Functional characterisation of a tropine-forming reductase gene from Brugmansia arborea, a woody plant species producing tropane alkaloids

Publication date: July 2016
Source:Phytochemistry, Volume 127

Author(s): Wei Qiang, Ke Xia, Qiaozhuo Zhang, Junlan Zeng, Yuanshe Huang, Chunxian Yang, Min Chen, Xiaoqiang Liu, Xiaozhong Lan, Zhihua Liao

Brugmansia arborea is a woody plant species that produces tropane alkaloids (TAs). The gene encoding tropine-forming reductase or tropinone reductase I (BaTRI) in this plant species was functionally characterised. The full-length cDNA of BaTRI encoded a 272-amino-acid polypeptide that was highly similar to tropinone reductase I from TAs-producing herbal plant species. The purified 29kDa recombinant BaTRI exhibited maximum reduction activity at pH 6.8–8.0 when tropinone was used as substrate; it also exhibited maximum oxidation activity at pH 9.6 when tropine was used as substrate. The Km, Vmax and Kcat values of BaTRI for tropinone were 2.65mM, 88.3nkatmg−1 and 2.93S−1, respectively, at pH 6.4; the Km, Vmax and Kcat values of TRI from Datura stramonium (DsTRI) for tropinone were respectively 4.18mM, 81.20nkatmg−1 and 2.40S−1 at pH 6.4. At pH 6.4, 6.8 and 7.0, BaTRI had a significantly higher activity than DsTRI. Analogues of tropinone, 4-methylcyclohexanone and 3-quinuclidinone hydrochloride, were also used to investigate the enzymatic kinetics of BaTRI. The Km, Vmax and Kcat values of BaTRI for tropine were 0.56mM, 171.62nkat.mg−1 and 5.69S−1, respectively, at pH 9.6; the Km, Vmax and Kcat values of DsTRI for tropine were 0.34mM, 111.90nkatmg−1 and 3.30S−1, respectively, at pH 9.6. The tissue profiles of BaTRI differed from those in TAs-producing herbal plant species. BaTRI was expressed in all examined organs but was most abundant in secondary roots. Finally, tropane alkaloids, including hyoscyamine, anisodamine and scopolamine, were detected in various organs of B. arborea by HPLC. Interestingly, scopolamine constituted most of the tropane alkaloids content in B. arborea, which suggests that B. arborea is a scopolamine-rich plant species. The scopolamine content was much higher in the leaves and stems than in other organs. The gene expression and TAs accumulation suggest that the biosynthesis of hyoscyamine, especially scopolamine, occurred not only in the roots but also in the aerial parts of B. arborea.

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Datum: 05.05.2016


Steroidal saponins from Chlorophytum deistelianum

Publication date: June 2016
Source:Phytochemistry, Volume 126

Author(s): Turibio Kuiate Tabopda, Anne-Claire Mitaine-Offer, Thomas Paululat, Stéphanie Delemasure, Patrick Dutartre, Bonaventure Tchaleu Ngadjui, Marie-Aleth Lacaille-Dubois

Phytochemical investigation of the aerial parts of Chlorophytum deistelianum led to the isolation of four previously undescribed steroidal saponins called chlorodeistelianosides A–D with five known ones. Their structures were established mainly by extensive 1D and 2D NMR spectroscopic techniques and mass spectrometry as (25R)-3β-[(β-d-glucopyranosyl-(13)-[α-l-rhamnopyranosyl-(14)]-β-d-xylopyranosyl-(13)-[β-d-glucopyranosyl-(12)]-β-d-glucopyranosyl-(14)-β-d-galactopyranosyl)oxy]-5α-spirostan-12-one, (24S,25S)-24-[(β-d-glucopyranosyl)oxy]-3β-[(β-d-glucopyranosyl-(12)-[β-d-xylopyranosyl-(13)]-β-d-glucopyranosyl-(14)-β-d-galactopyranosyl)oxy]-5α-spirostan-12-one, (25R)-26-[(β-d-glucopyranosyl)oxy]-2α-hydroxy-22α-methoxy-5α-furostan-3β-yl β-d-glucopyranosyl-(12)-[β-d-xylopyranosyl-(13)]-β-d-glucopyranosyl-(14)-β-d-galactopyranoside, and (25R)-26-[(β-d-glucopyranosyl)oxy]-3β-[(β-d-glucopyranosyl-(12)-[β-d-xylopyranosyl-(13)]-β-d-glucopyranosyl-(14)-β-d-galactopyranosyl)oxy]-5α-furost-20(22)-en-12-one. Cytotoxicity of most compounds was evaluated against one human cancer cell line (SW480) and one rat cardiomyoblast cell line (H9c2). Among them, three known spirostane-type glycosides exhibited cytotoxicity on both cell lines with IC50 ranging from 8 to 10μM.

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Datum: 05.05.2016


Terpenoids from Flueggea virosa and their anti-hepatitis C virus activity

Publication date: Available online 21 April 2016
Source:Phytochemistry

Author(s): Chih-Hua Chao, Ju-Chien Cheng, De-Yang Shen, Hui-Chi Huang, Yang-Chang Wu, Tian-Shung Wu

Phytochemical study of the methanolic root extract of Flueggea virosa allowed for the characterization of 18 non-alkaloid terpenoids. Their structures have skeletons composed of six rearranged ent-podocarpanes, 11 ent-podocarpanes, and a 3,4-seco-30-nor-friedelane. These were characterized based on 2D NMR, IR, UV, and MS spectroscopic analysis and their absolute configurations were determined by single-crystal X-ray studies, as well as by 1H NMR spectroscopic analysis for the corresponding chiral derivatives. The isolates were evaluated for therapeutic potential against hepatitis C virus (HCV) infection to human hepatoma Huh7.5 cells.

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Datum: 05.05.2016


Polyoxypregnane steroids with an open-chain sugar moiety from Marsdenia tenacissima and their chemoresistance reversal activity

Publication date: June 2016
Source:Phytochemistry, Volume 126

Author(s): Sheng Yao, Kenneth Kin-Wah To, Liang Ma, Chun Yin, Chunping Tang, Stella Chai, Chang-Qiang Ke, Ge Lin, Yang Ye

A polyoxypregnane aglycone, 12β-O-acetyl-11α-O-isobutyryltenacigenin B, and four polyoxypregnane glycosides with a pachybionic acid ester moiety, 12β-O-acetyl-3-O-(6-deoxy-3-O-methyl-β-d-allopyranosyl-(1→4)-β-d-oleandronyl)-11α-O-isobutyryltenacigenin B, 12β-O-acetyl-3-O-(6-deoxy-3-O-methyl-β-d-allopyranosyl-(1→4)-β-d-oleandronyl)-11α-O-tigloyltenacigenin B, 12β-O-acetyl-3-O-(6-deoxy-3-O-methyl-β-d-allopyranosyl-(1→4)-β-d-oleandronyl)-11α-O-2-methylbutyryltenacigenin B, and 12β-O-acetyl-3-O-(β-d-glucopyranosyl-(1→4)-6-deoxy-3-O-methyl-β-d-allopyranosyl-(1→4)-d-oleandronyl)-11α-O-tigloyltenacigenin B, were isolated from the canes of Marsdenia tenacissima, together with a disaccharide derivative. Their structures were elucidated by extensive spectroscopic analysis, and the absolute configurations were further determined by X-ray crystallographic analysis. With the exception of the disaccharide derivative, all five compounds are unusual naturally occurring polyoxypregnane glycosides bearing an open-chain sugar moiety. Two of these exhibit a wide spectrum of chemoresistance reversal activity, and potential mechanisms were studied accordingly.

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Datum: 05.05.2016


Functional characterization of CYP71D443, a cytochrome P450 catalyzing C-22 hydroxylation in the 20-hydroxyecdysone biosynthesis of Ajuga hairy roots

Publication date: July 2016
Source:Phytochemistry, Volume 127

Author(s): Yuki Tsukagoshi, Kiyoshi Ohyama, Hikaru Seki, Tomoyoshi Akashi, Toshiya Muranaka, Hideyuki Suzuki, Yoshinori Fujimoto

20-Hydroxyecdysone (20HE), a molting hormone of insects, is also distributed among a variety of plant families. 20HE is thought to play a role in protecting plants from insect herbivores. In insects, biosynthesis of 20HE from cholesterol proceeds via 7-dehydrocholesterol and 3β,14α-dihydroxy-5β-cholest-7-en-6-one (5β-ketodiol), the latter being converted to 20HE through sequential hydroxylation catalyzed by four P450 enzymes, which have been cloned and identified. In contrast, little is known about plant 20HE biosynthesis, and no biosynthetic 20HE gene has been reported thus far. We recently proposed involvement of 3β-hydroxy-5β-cholestan-6-one (5β-ketone) in 20HE biosynthesis in the hairy roots of Ajuga reptans var. atropurpurea (Lamiaceae). In this study, an Ajuga EST library was generated from the hairy roots and P450 genes were deduced from the library. Five genes with a high expression level (CYP71D443, CYP76AH19, CYP76AH20, CYP76AH21 and CYP716D27) were screened for a possible involvement in 20HE biosynthesis. As a result, CYP71D443 was shown to have C-22 hydroxylation activity for the 5β-ketone substrate using a yeast expression system. The hydroxylated product, 22-hydroxy-5β-ketone, had a 22R configuration in agreement with that of 20HE. Furthermore, labeling experiments indicated that (22R)-22-hydroxy-5β-ketone was converted to 20HE in Ajuga hairy roots. Based on the present results, a possible 20HE biosynthetic pathway in Ajuga plants involved CYP71D443 is proposed.

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Datum: 05.05.2016


Phytochemical Society of Europe

Publication date: June 2016
Source:Phytochemistry, Volume 126










Datum: 05.05.2016


Exploring occurrence and molecular diversity of betaine lipids across taxonomy of marine microalgae

Publication date: April 2016
Source:Phytochemistry, Volume 124

Author(s): José Pedro Cañavate, Isabel Armada, José Luis Ríos, Ismael Hachero-Cruzado

Betaine lipids (BL) from ten microalgae species of the kingdoms Plantae and Chromista were identified and quantified by HPLC/ESI-TOF-MS. Diacylgyceryl-N-trimethylhomoserine (DGTS) was detected in Trebouxiophyceae and Eustigmatophyceae species, whereas Tetraselmis suecica was described as the first green algae containing diacylglyceryl-hydroxymethyl-N,N,N-trimethyl-beta-alanine (DGTA). DGTA molecular species where also characterized in Cryptophyceae species as well as in the Bacillariophyceae diatom Phaeodactylum tricornutum. The Mediophyceae diatom Chaetoceros gracilis had no DGTA, but contained diacylglyceryl-carboxyhydroxymethylcholine (DGCC). A principal coordinate (PCO) analysis of microalgae species revealed the existence of three main clusters around each BL type. The first PCO axis (43.9% of total variation) grouped Chlorophyceae, Trebouxiophyceae and Eustigmatophyceae species and positively correlated with DGTS. The second PCO axis (27.8% of total variation) segregated DGTA from DGCC containing species. Cryptophyceae, Bacillariophyceae and Chlorodendrophyceae were the more closely associated species to DGTA. Mediophyceae and Dinophyceae species contained DGCC as the only BL. Molecular diversity varied from the simplest DGCC composition in Gyrodinium dorsum to the highest spectrum of ten different molecular species detected for DGTA (Rhodomonas baltica) and DGCC (C. gracilis). The fatty acid profile of DGTS was very dissimilar to that of the whole lipid cell content. DGTS from Nannochloropsis gaditana was highly unsaturated respecting to total lipids, whereas in Picochlorum atomus DGTS unsaturation was nearly one half to that of total lipids. Dissimilarity between DGTA and total lipid fatty acid profile was minimum among all BL and DGTA fatty acid unsaturation was the maximum observed in the study. New DGCC molecular species enriched in 20:5 were described in Mediophyceae diatoms. Multivariate microalgae ordination using BL as descriptors revealed a higher chemotaxonomic potential than that based on their respective BL fatty acid profile. Nevertheless, taxonomic resolution was improved when fatty acids from the whole cell lipid pool were used.

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Datum: 05.05.2016


Graphical Contents List

Publication date: May 2016
Source:Phytochemistry, Volume 125










Datum: 05.05.2016


Distinguishing commercially grown Ganoderma lucidum from Ganoderma lingzhi from Europe and East Asia on the basis of morphology, molecular phylogeny, and triterpenic acid profiles

Publication date: July 2016
Source:Phytochemistry, Volume 127

Author(s): Florian Hennicke, Zakaria Cheikh-Ali, Tim Liebisch, Jose G. Maciá-Vicente, Helge B. Bode, Meike Piepenbring

In China and other countries of East Asia, so-called Ling-zhi or Reishi mushrooms are used in traditional medicine since several centuries. Although the common practice to apply the originally European name ‘Ganoderma lucidum’ to these fungi has been questioned by several taxonomists, this is still generally done in recent publications and with commercially cultivated strains. In the present study, two commercially sold strains of ‘G. lucidum’, M9720 and M9724 from the company Mycelia bvba (Belgium), are compared for their fruiting body (basidiocarp) morphology combined with molecular phylogenetic analyses, and for their secondary metabolite profile employing an ultra-performance liquid chromatography–electrospray ionization mass spectrometry (UPLC–ESIMS) in combination with a high resolution electrospray ionization mass spectrometry (HR-ESI-MS). According to basidiocarp morphology, the strain M9720 was identified as G. lucidum s.str. whereas M9724 was determined as Ganoderma lingzhi. In molecular phylogenetic analyses, the M9720 ITS and beta-tubulin sequences grouped with sequences of G. lucidum s.str. from Europe whereas those from M9724 clustered with sequences of G. lingzhi from East Asia. We show that an ethanol extract of ground basidiocarps from G. lucidum (M9720) contains much less triterpenic acids than found in the extract of G. lingzhi (M9724). The high amount of triterpenic acids accounts for the bitter taste of the basidiocarps of G. lingzhi (M9724) and of its ethanol extract. Apparently, triterpenic acids of G. lucidum s.str. are analyzed here for the first time. These results demonstrate the importance of taxonomy for commercial use of fungi.

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Datum: 05.05.2016


Proteomic analysis of mature barley grains from C-hordein antisense lines

Publication date: May 2016
Source:Phytochemistry, Volume 125

Author(s): Daiana Schmidt, Salete Aparecida Gaziola, Luis Felipe Boaretto, Ricardo Antunes Azevedo

Hordeins are the major storage proteins in barley grains and are responsible for their low nutritional quality. Previously, antisense C-hordein barley lines were generated and were shown to contain a more balanced amino acid composition and an altered storage protein profile. In the present study, a proteomic approach that combined two-dimensional gel electrophoresis (2-DE) and mass spectrometry was used to (1) identify the changes in the protein profile of non-storage proteins (salt soluble fraction) in antisense C-hordein barley lines (L1, L2 and L3) and (2) map the differentially expressed proteins compared to the non-transgenic control line (Hordeum vulgare cv. Golden Promise). Moreover, the changes in the proteins were correlated with the more balanced amino acid composition of these lines, with special attention to the lysine content. The results showed that suppression of C-hordein expression does not exclusively affect hordein synthesis and accumulation. The more balanced amino acid composition observed in the transgenic lines L1, L2 and L3 was an indirect result of the profound alterations in the patterns of the non-storage proteins. The observed changes included up-regulated expression of the proteins involved in stress and detoxification (L1), defence (L2 and L3), and storage globulins (L1, L2 and L3). To a lesser extent, the proteins involved in grain metabolism were also changed. Thus, the increased essential amino acids content results from changes in distinct protein sources among the three antisense C-hordein lines analyzed, although the up-regulated expression of lysine-rich proteins was consistently observed in all lines.

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Datum: 05.05.2016


Editorial Board/Publication Information

Publication date: July 2016
Source:Phytochemistry, Volume 127










Datum: 05.05.2016


Developmental patterning and segregation of alkaloids in areca nut (seed of Areca catechu) revealed by magnetic resonance and mass spectrometry imaging

Publication date: May 2016
Source:Phytochemistry, Volume 125

Author(s): Amitava Srimany, Christy George, Hemanta R. Naik, Danica Glenda Pinto, N. Chandrakumar, T. Pradeep

Areca nut (seed of Areca catechu) is consumed by people from different parts of Asia, including India. The four major alkaloids present in areca nut are arecoline, arecaidine, guvacoline and guvacine. Upon cutting, the nut reveals two kinds of regions; white and brown. In our present study, we have monitored the formation of these two regions within the nut during maturation, using the non-invasive techniques of magnetic resonance imaging (MRI) and volume localized magnetic resonance spectroscopy (MRS). Electrospray ionization mass spectrometry (ESI MS) and desorption electrospray ionization mass spectrometry (DESI MS) imaging have been used to study the associated change in the alkaloid contents of these two regions during the growth of the nut. Our study reveals that white and brown regions start forming within the nut when the liquid within starts solidifying. At the final stage of maturity, arecoline, arecaidine and guvacoline get segregated in the brown region whereas guvacine gets to the white region of the nut. The transport of molecules with maturity and corresponding pattern formation are expected to be associated with a multitude of physiochemical changes.

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Datum: 05.05.2016


Prenylfuranocoumarin–HMGA–flavonol glucoside conjugates and other constituents of the fruit peels of Citrus hystrix and their anticholinesterase activity

Publication date: July 2016
Source:Phytochemistry, Volume 127

Author(s): Chonticha Seeka, Pakawadee Sutthivaiyakit, Juthamanee Youkwan, Norbert Hertkorn, Mourad Harir, Philippe Schmitt-Kopplin, Somyote Sutthivaiyakit

Sixteen compounds including dihydroxy prenylfuranocoumarins/3-hydroxy-3-methylglutaric acid conjugates and dihydroxy prenylfuranocoumarins/3-hydroxy-3-methylglutaric acid/1-O-flavonyl-β-d-glucopyranoside conjugates, together with other dihydroxyprenylfuranocoumarins conjugates, were isolated from the ethyl acetate extract of the fruit peels of Citrus hystrix. Some of the isolates were evaluated for their cholinesterase inhibitory activity, but only one compound possessing a 3-O-β-d-glucopyranosyl-3,5,7,4′-tetrahydroxy-6,8,3′-trimethoxyflavonol nucleus in the prenylfuranocoumarin–HMGA conjugate showed strong activity.

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Datum: 05.05.2016


Regulation of sesquiterpenoid metabolism in recombinant and elicited Valeriana officinalis hairy roots

Publication date: May 2016
Source:Phytochemistry, Volume 125

Author(s): Vincent Ricigliano, Santosh Kumar, Scott Kinison, Christopher Brooks, S. Eric Nybo, Joe Chappell, Dianella G. Howarth

The medicinal properties of Valerian (Valeriana officinalis) root preparations are attributed to the anxiolytic sesquiterpenoid valerenic acid and its biosynthetic precursors valerenal and valerenadiene, as well as the anti-inflammatory sesquiterpenoid β-caryophyllene. In order to study and engineer the biosynthesis of these pharmacologically active metabolites, a binary vector co-transformation system was developed for V. officinalis hairy roots. The relative expression levels and jasmonate-inducibility of a number of genes associated with sesquiterpenoid metabolism were profiled in roots: farnesyl pyrophosphate synthase (VoFPS), valerendiene synthase (VoVDS), germacrene C synthase (VoGCS), and a cytochrome P450 (CYP71D442) putatively associated with terpene metabolism based on sequence homology. Recombinant hairy root lines overexpressing VoFPS or VoVDS were generated and compared to control cultures. Overexpression of the VoFPS cDNA increased levels of the corresponding transcript 4- to 8-fold and sesquiterpene hydrocarbon accumulation by 1.5- to 4-fold. Overexpression of the VoVDS cDNA increased the corresponding transcript levels 5- to 9-fold and markedly increased yields of the oxygenated sesquiterpenoids valerenic acid and valerenal. Our findings suggest that the availability of cytoplasmic farnesyl diphosphate and valerenadiene are potential bottlenecks in Valeriana-specific sesquiterpenoid biosynthesis, which is also subject to regulation by methyl jasmonate elicitation.

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Datum: 05.05.2016


Biosynthesis of natural and novel C-glycosylflavones utilising recombinant Oryza sativa C-glycosyltransferase (OsCGT) and Desmodium incanum root proteins

Publication date: May 2016
Source:Phytochemistry, Volume 125

Author(s): B. Hao, J.C. Caulfield, M.L. Hamilton, J.A. Pickett, C.A.O. Midega, Z.R. Khan, J. Wang, A.M. Hooper

The rice C-glycosyltransferase (OsCGT) is one of only a small number of characterised plant C-glycosyltransferases (CGT) known. The enzyme C-glucosylates a 2-hydroxyflavanone substrate with UDP-glucose as the sugar donor to produce C-glucosyl-2-hydroxyflavanones. We tested substrate specificity of the enzyme, using synthetic 2-hydroxyflavanones, and showed it has the potential to generate known natural CGFs that have been isolated from rice and also other plants. In addition, we synthesised novel, unnatural 2-hydroxyflavanone substrates to test the B-ring chemical space of substrate accepted by the OsCGT and demonstrated the OsCGT capacity as a synthetic reagent to generate significant quantities of known and novel CGFs. Many B-ring analogues are tolerated within a confined steric limit. Finally the OsCGT was used to generate novel mono-C-glucosyl-2-hydroxyflavanones as putative biosynthetic intermediates to examine the potential of Desmodium incanum biosynthetic CGTs to produce novel di-C-glycosylflavones, compounds implicated in the allelopathic biological activity of Desmodium against parasitic weeds from the Striga genus.

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Datum: 05.05.2016


Biological activity of ellagitannins: Effects as anti-oxidants, pro-oxidants and metal chelators

Publication date: May 2016
Source:Phytochemistry, Volume 125

Author(s): Johanna Moilanen, Maarit Karonen, Petri Tähtinen, Rémi Jacquet, Stéphane Quideau, Juha-Pekka Salminen

Ellagitannins are a subclass of hydrolysable tannins that have been suggested to function as defensive compounds of plants against herbivores. However, it is known that the conditions in the digestive tracts of different herbivores are variable, so it seems reasonable to anticipate that the reactivities and modes of actions of these ingested defensive compounds would also be different. A previous study on a few ellagitannins has shown that these polyphenolic compounds are highly oxidizable at high pH and that their bioactivity can be attributed to certain structural features. Herein, the activities of 13 ellagitannins using the deoxyribose assay were measured. The results provided information about the anti-oxidant, pro-oxidant and metal chelating properties of ellagitannins. Surprisingly, many of the tested ellagitannins exhibited pro-oxidant activities even at neutral pH and only moderate to low radical scavenging activities, although the metal chelating capacities of all tested ellagitannins were relatively high.

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Datum: 05.05.2016


Phenylethanoid glycosides and phenolic glycosides from stem bark of Magnolia officinalis

Publication date: July 2016
Source:Phytochemistry, Volume 127

Author(s): Zhenzhen Xue, Renyi Yan, Bin Yang

An investigation of the hydrophilic constituents of the stem bark of Magnolia officinalis was performed and which led to isolation and identification of twenty-one previously unreported glycosides. These included eleven phenylethanoid glycosides, magnolosides F–P, and ten phenolic glycosides, magnolosides Q–Z, along with eight known compounds. Their structures were elucidated on the basis of extensive spectroscopic analyses and chemical hydrolysis methods, as well as by comparison with literature data. Most of the phenylethanoid glycosides contained an allopyranose moiety, which is rare in the plant kingdom. Magnolosides I and K as well as 2-(3,4-dihydroxyphenyl) ethanol 1-O-[4-O-caffeoyl-2-O-α- l -rhamnopyranosyl-3-O-α- l -rhamnopyranosyl-6-O-β- d -glucopyranosyl]-β- d -glucopyranoside showed more potent α-glucosidase inhibitory effects (IC50 values of 0.13, 0.27, and 0.29mM, respectively) than the positive control, acarbose (IC50 value of 1.09mM) in vitro. Magnolosides H, E and D also showed moderate cytotoxicity against MGC-803 and HepG2 cells with IC50 values of 13.59–17.16μM and 29.53–32.46μM, respectively.

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Datum: 05.05.2016


Galactinol synthase enzyme activity influences raffinose family oligosaccharides (RFO) accumulation in developing chickpea (Cicer arietinum L.) seeds

Publication date: May 2016
Source:Phytochemistry, Volume 125

Author(s): Manu P. Gangola, Sarita Jaiswal, Udhaya Kannan, Pooran M. Gaur, Monica Båga, Ravindra N. Chibbar

To understand raffinose family oligosaccharides (RFO) metabolism in chickpea (Cicer arietinum L.) seeds, RFO accumulation and corresponding biosynthetic enzymes activities were determined during seed development of chickpea genotypes with contrasting RFO concentrations. RFO concentration in mature seeds was found as a facilitator rather than a regulating step of seed germination. In mature seeds, raffinose concentrations ranged from 0.38 to 0.68 and 0.75 to 0.99g/100g, whereas stachyose concentrations varied from 0.79 to 1.26 and 1.70 to 1.87g/100g indicating significant differences between low and high RFO genotypes, respectively. Chickpea genotypes with high RFO concentration accumulated higher concentrations of myo-inositol and sucrose during early seed developmental stages suggesting that initial substrate concentrations may influence RFO concentration in mature seeds. High RFO genotypes showed about two to three-fold higher activity for all RFO biosynthetic enzymes compared to those with low RFO concentrations. RFO biosynthetic enzymes activities correspond with accumulation of individual RFO during seed development.

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Datum: 05.05.2016


Phytochemical Society of Europe

Publication date: May 2016
Source:Phytochemistry, Volume 125










Datum: 05.05.2016


Synthesis of rebaudioside A from stevioside and their interaction model with hTAS2R4 bitter taste receptor

Publication date: May 2016
Source:Phytochemistry, Volume 125

Author(s): Ramit Singla, Vikas Jaitak

Steviol glycosides (SG’s) from Stevia rebaudiana (Bertoni) have been used as a natural low-calorie sweeteners. Its aftertaste bitterness restricts its use for human consumption and limits its application in food and pharmaceutical products. In present study, we have performed computational analysis in order to investigate the interaction of two major constituents of SG’s against homology model of the hTAS2R4 receptor. Molecular simulation study was performed using stevioside and rebaudioside A revealed that, sugar moiety at the C-3′′ position in rebaudioside A causes restriction of its entry into the receptor site thereby unable to trigger the bitter reception signaling cascade. Encouraged by the current finding, we have also developed a greener route using β-1,3-glucanase from Irpex lacteus for the synthesis of de-bittered rebaudioside A from stevioside. The rebaudioside A obtained was of high quality with percent conversion of 62.5%. The results here reported could be used for the synthesis of rebaudioside A which have large application in food and pharmaceutical industry.

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Datum: 05.05.2016


Structures and biological activities of triterpenes and sesquiterpenes obtained from Russula lepida

Publication date: July 2016
Source:Phytochemistry, Volume 127

Author(s): Jong-Soo Lee, Wilmar Maarisit, Delfly B. Abdjul, Hiroyuki Yamazaki, Ohgi Takahashi, Ryota Kirikoshi, Syu-ichi Kanno, Michio Namikoshi

A seco-cucurbitane triterpene and two aristolane sesquiterpenes, named (24E)-3,4-seco-cucurbita-4,24-diene-3-hydroxy-26,29-dioic acid, (+)-1,2-didehydro-9-hydroxy-aristlone, and (+)-12-hydroxy-aristlone, were isolated from fruiting bodies of the medicinal mushroom Russula lepida, together with (24E)-3,4-seco-cucurbita-4,24-diene-3,26,29-trioic acid and (+)-aristlone. The structures of the first three compounds, including their absolute configurations, were assigned on the basis of their NMR and ECD spectra. Two seco-cucurbitane triterpenes, (24E)-3,4-seco-cucurbita-4,24-diene-3-hydroxy-26,29-dioic acid and (24E)-3,4-seco-cucurbita-4,24-diene-3,26,29-trioic acid, inhibited the activity of protein tyrosine phosphatase 1B (PTP1B), with IC50 values of 20.3 and 0.4μM, respectively. All isolated compounds did not show cytotoxicity against human cancer cell lines, Huh-7 (hepatoma) and EJ-1 (bladder), at 50μM.

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Datum: 05.05.2016


HIV-inhibitory michellamine-type dimeric naphthylisoquinoline alkaloids from the Central African liana Ancistrocladus congolensis

Publication date: Available online 29 April 2016
Source:Phytochemistry

Author(s): Gerhard Bringmann, Claudia Steinert, Doris Feineis, Virima Mudogo, Julia Betzin, Carsten Scheller

Five michellamine-type dimeric naphthylisoquinoline alkaloids (NIQs), named michellamines A2, A3, A4, B2, and B3, have been isolated from the root bark of the Central African liana Ancistrocladus congolensis J. L é onard (Ancistrocladaceae), along with their two known parent compounds, the michellamines A and B, which had so far only been detected in the Cameroonian species Ancistrocladus korupensis. Five monomeric representatives, viz., korupensamine D, ancistrobrevine B, hamatine, 5′-O-demethylhamatine, and 6-O-methylhamatine, already known from related Ancistrocladus species, have likewise been identified. The structure elucidation was achieved by spectroscopic analysis including HRESIMS, 1D and 2D NMR, and by chemical and chiroptical methods. The michellamines A2, A3, B3, and A4 were evaluated for their cytotoxic and anti-HIV activities at a concentration range of 0–100 μM against the HIV reference strain IIIB/LAI in A3.01 T lymphoblast cell cultures, and their effects were compared to the ones displayed by the known michellamines A and B. Inhibitory activities for HIV replication were monitored for the michellamines A2 (IC50 = 29.6 μM), A3 (IC50 = 15.2 μM), A4 (IC50 = 35.9 μM), and B (IC50 = 20.4 μM). The michellamines A and B3, by contrast, did not inhibit HIV replication. No cytotoxicity was observed. Furthermore, the chemotaxonomic significance of the previously undescribed michellamines is discussed.

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Datum: 05.05.2016


Graphical Contents List

Publication date: April 2016
Source:Phytochemistry, Volume 124










Datum: 05.05.2016


Editorial Board/Publication Information

Publication date: April 2016
Source:Phytochemistry, Volume 124










Datum: 05.05.2016


Editorial Board/Publication Information

Publication date: June 2016
Source:Phytochemistry, Volume 126










Datum: 05.05.2016


Secondary metabolites of seagrasses (Alismatales and Potamogetonales; Alismatidae): Chemical diversity, bioactivity, and ecological function

Publication date: April 2016
Source:Phytochemistry, Volume 124

Author(s): Christian Zidorn

Seagrasses are the only higher plants living in fully marine environments; they play a significant role in coastal ecosystems. Seagrasses inhabit the coastal shelves of all continents except Antarctica and can grow in depths of up to 90m. Because of their eminent ecological importance, innumerous studies have been dedicated to seagrasses and their ecology. However, the phytochemistry has not been equally well investigated yet and many of the existing studies in chemical ecology are only investigating the chemistry at the level of compound classes, e.g. phenolics, and not at the level of chemically defined metabolites. In the present review, the existing literature on secondary metabolites of seagrasses, their known source seagrasses, their bioactivity, and ecological function are compiled and critically assessed. Moreover, research gaps are highlighted and avenues for future research are discussed. Currently, a total of 154 chemically defined natural products have been reported from the about 70 seagrass species known worldwide. Compounds reported include simple phenols derivatives (four compounds), phenylmethane derivatives (14 compounds), phenylethane derivatives (four compounds), phenylpropane derivatives including their esters and dimers (20 compounds), chalkones (four compounds), flavonoids including catechins (57 compounds), phenylheptanoids (four compounds), one monoterpene derivative, one sesquiterpene, diterpenoids (13 compounds), steroids (31 compounds), and one alkaloid. Most of the existing bioactivity studies of seagrass metabolites and extracts have been directed to potential cytotoxic, antimicrobial, or antimacrofouling activity. Antimicrobial studies have been performed towards panels of both human pathogens and ecologically relevant pathogens. In the antimacrofouling studies, investigations of the potential of zosteric acid from the genus Zostera are the most numerous and have yielded so far the most interesting results. Studies on the chemical ecology of seagrasses often have been focused on variation in phenolic compounds and include but are not limited to studies on variation due to abiotic factors, seasonal variation, variation in response to grazing by fish or sea urchins, or following microbial attack.

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Datum: 05.05.2016


Dynamic metabolic changes in seeds and seedlings of Brassica napus (oilseed rape) suppressing UGT84A9 reveal plasticity and molecular regulation of the phenylpropanoid pathway

Publication date: April 2016
Source:Phytochemistry, Volume 124

Author(s): Karina Hettwer, Christoph Böttcher, Andrej Frolov, Juliane Mittasch, Andreas Albert, Edda von Roepenack-Lahaye, Dieter Strack, Carsten Milkowski

In Brassica napus, suppression of the key biosynthetic enzyme UDP-glucose:sinapic acid glucosyltransferase (UGT84A9) inhibits the biosynthesis of sinapine (sinapoylcholine), the major phenolic component of seeds. Based on the accumulation kinetics of a total of 158 compounds (110 secondary and 48 primary metabolites), we investigated how suppression of the major sink pathway of sinapic acid impacts the metabolome of developing seeds and seedlings. In UGT84A9-suppressing (UGT84A9i) lines massive alterations became evident in late stages of seed development affecting the accumulation levels of 58 secondary and 7 primary metabolites. UGT84A9i seeds were characterized by decreased amounts of various hydroxycinnamic acid (HCA) esters, and increased formation of sinapic and syringic acid glycosides. This indicates glycosylation and β-oxidation as metabolic detoxification strategies to bypass intracellular accumulation of sinapic acid. In addition, a net loss of sinapic acid upon UGT84A9 suppression may point to a feedback regulation of HCA biosynthesis. Surprisingly, suppression of UGT84A9 under control of the seed-specific NAPINC promoter was maintained in cotyledons during the first two weeks of seedling development and associated with a reduced and delayed transformation of sinapine into sinapoylmalate. The lack of sinapoylmalate did not interfere with plant fitness under UV-B stress. Increased UV-B radiation triggered the accumulation of quercetin conjugates whereas the sinapoylmalate level was not affected.

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Datum: 05.05.2016


Cyclofarnesoids and methylhexanoids produced from β-carotene in Phycomyces blakesleeanus

Publication date: April 2016
Source:Phytochemistry, Volume 124

Author(s): Eugenio Alcalde, Humberto R. Medina, M. Mar Herrador, Alejandro F. Barrero, Enrique Cerdá-Olmedo

The oxidative cleavage of β-carotene in the Mucorales produces three fragments of 18, 15, and 7 carbons, respective heads of three families of apocarotenoids: the methylhexanoids, the trisporoids, and the cyclofarnesoids (named after their 1,6-cyclofarnesane skeleton). The apocarotenoids are easily recognized because they are absent in white mutants unable to produce β-carotene. In cultures of Phycomyces blakesleeanus we detected thirty-two apocarotenoids by LC, UV absorbance, and MS. With additional IR and NMR we identified two methylhexanoids and the eight most abundant cyclofarnesoids. Four of them were previously-unknown natural compounds, including 4-dihydrocyclofarnesine S, the most abundant cyclofarnesoid in young cultures. We arranged the apocarotenoids of the Mucorales in a scheme that helps classifying and naming them and suggests possible metabolites and biosynthetic pathways. We propose specific biosynthetic pathways for cyclofarnesoids and methylhexanoids based on structural comparisons, the time course of appearance of individual compounds, and the bioconversion of β-apo-12-carotenol, an early precursor, to three more oxygenated cyclofarnesoids by the white mutants. Some of the reactions occur spontaneously in the increasingly acidic culture media. Mating increased the contents of methylhexanoids and cyclofarnesoids by ca. threefold in young cultures and ca. twelvefold in old ones (five days); cyclofarnesine S, the most abundant cyclofarnesoid in old cultures, increased over one hundredfold. We found no differences between the sexes and no activity as sexual pheromones, but we suggest that methylhexanoids and cyclofarnesoids could mediate species-specific physiology and behavior.

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Datum: 05.05.2016


Graphical Contents List

Publication date: June 2016
Source:Phytochemistry, Volume 126










Datum: 05.05.2016


Metabolite profiles of essential oils and molecular markers analysis to explore the biodiversity of Ferula communis: Towards conservation of the endemic giant fennel

Publication date: April 2016
Source:Phytochemistry, Volume 124

Author(s): Fatma Zohra Rahali, Myriam Lamine, Mahmoud Gargouri, Iness Bettaieb Rebey, Majdi Hammami, Ibtissem Hamrouni Sellami

Giant fennel (Ferula communis L.) is well known in folk medicine for the treatment of various organ disorders. The biological importance of members of genus Ferula prompted us to investigate the leaves of the endangered Tunisian medicinal plant F. communis L. not previously investigated. An estimate of genetic diversity and differentiation between genotypes of breeding germplasm is of key importance for its improvement. Thus, four F. communis populations were RAPD fingerprinted (63 RAPD markers generated by 7 primers) and the composition of their leaf essential oils (EO) (134 EO compounds) was characterized by GC–MS. Cluster analysis based on the leaf volatiles chemical composition of F. communis accessions defined three chemotypes according to main compounds have been distinguished: α-eudesmol/β-eudesmol/γ-terpinene; α-eudesmol/α-pinene/caryophyllene oxide and chamazulene/α-humulene chemotypes. A high genetic diversity within population and high genetic differentiation among them, based on RAPDs, were revealed (H pop =0.320 and G ST =0.288) caused both by the habitat fragmentation, the low size of most populations and the low level of gene flow among them. The RAPD dendrogram showed separation of three groups. Populations dominated by individuals from the β-eudesmol/γ-terpinene; chemotype showed the lowest gene diversity (H =0.104), while populations with exclusively α-pinene/caryophyllene oxide chemotype showed the highest value (H =0.285). The UPGMA dendrogram and PCA analysis based on volatiles yielded higher separation among populations, indicated specific adaptation of populations to the local environments. Correlation analysis showed a non-significant association between the distance matrices based on the genetic markers (RAPD) and chemical compounds of essential oil (P >0.05) indicating no influence of genetic background on the observed chemical profiles. These results reinforce the use of both volatile compounds and RAPD markers as a starting point for in situ conservation. The analysis of chemical constitution of oil of the populations from a specific region revealed predominance of specific constituents indicating possibility of their collection/selection for specific end uses like phytomedicines. Sufficient molecular and biochemical diversity detected among natural populations of this species will form the basis for the future improvement. The correlation between matrices of RAPD and essential oils was not significant. The conservation strategies of populations should be made according to their level of genetic and chemical diversity in relation to geographic location of populations. Our results give some insights into the characterization of this as yet little investigated plant.

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Datum: 05.05.2016


Sesquiterpenoids and tirucallane triterpenoids from the roots of Scorzonera divaricata

Publication date: April 2016
Source:Phytochemistry, Volume 124

Author(s): Yong-Jin Yang, Juan Yao, Xiao-Jie Jin, Zhuan-Ning Shi, Tian-Fei Shen, Jian-Guo Fang, Xiao-Jun Yao, Ying Zhu

A sulfated guaiane sesquiterpene lactone, an unusual pyridinium alkaloid with a sulfated guaiane sesquiterpene lactone nucleus, an amino conjugate of a sulfated guaiane sesquiterpene lactone, a bisabolane sesquiterpene, three tirucallane triterpenes, and six known compounds, were isolated from roots of Scorzonera divaricata. Their structures and absolute configurations were established based on chemical and spectroscopic methods, X-ray single crystal crystallography, and also by comparison with experimental and calculated ECD spectra. One of the tirucallane triterpenes exhibited significant cytotoxic activities against four human cancer cell lines (HL60, HeLa, HepG2, and SMMC-7721) in vitro. Two of sulfated guaiane sesquiterpenoids also exhibited antioxidant activities by scavenging ABTS cation free radicals. Tirucallane-type and dammarane-type triterpenes were not previously known in the genus Scorzonera. The study suggests that sulfated guaiane-type sesquiterpenoids are a valuable marker for systematic chemical studies in the Lactuceae tribe of the Asteraceae.

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Datum: 05.05.2016


Antibacterial and antifungal screening of natural products sourced from Australian fungi and characterisation of pestalactams D–F

Publication date: April 2016
Source:Phytochemistry, Volume 124

Author(s): Karren D. Beattie, Nicola Ellwood, Rohitesh Kumar, Xinzhou Yang, Peter C. Healy, Vanida Choomuenwai, Ronald J. Quinn, Alysha G. Elliott, Johnny X. Huang, Jessica L. Chitty, James A. Fraser, Matthew A. Cooper, Rohan A. Davis

Eighteen natural products sourced from Australian micro- or macro-fungi were screened for antibacterial and antifungal activity. This focused library was comprised of caprolactams, polyamines, quinones, and polyketides, with additional large-scale isolation studies undertaken in order to resupply previously identified compounds. Chemical investigations of the re-fermented culture from the endophytic fungus Pestalotiopsis sp. yielded three caprolactam analogues, pestalactams D–F, along with larger quantities of the known metabolite pestalactam A, which was methylated using diazomethane to yield 4-O-methylpestalactam A. The chemical structures of the previously undescribed fungal metabolites were determined by analysis of 1D/2D NMR and MS data. The structure of 4-O-methylpestalactam A was confirmed following single crystal X-ray diffraction analysis. The antibacterial and antifungal activity of all compounds was assessed, which identified three compounds, (1S,3R)-austrocortirubin, (1S,3S)-austrocortirubin, and 1-deoxyaustrocortirubin with mild activity (100μM) against Gram-positive isolates and one compound, 2-hydroxy-6-methyl-8-methoxy-9-oxo-9H-xanthene-1-carboxylic acid, with activity against Cryptococcus neoformans and Cryptococcus gattii at 50μM.

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Datum: 05.05.2016


Talarolutins A–D: Meroterpenoids from an endophytic fungal isolate of Talaromyces minioluteus

Publication date: June 2016
Source:Phytochemistry, Volume 126

Author(s): Amninder Kaur, Huzefa A. Raja, Dale C. Swenson, Rajesh Agarwal, Gagan Deep, Joseph O. Falkinham, Nicholas H. Oberlies

Four meroterpenoids [talarolutins A–D] and one known compound [purpurquinone A] were characterized from an endophytic fungal isolate of Talaromyces minioluteus (G413), which was obtained from the leaves of the medicinal plant milk thistle [Silybum marianum (L.) Gaertn. (Asteraceae)]. The structures of talarolutins A–D were determined by the analysis of various NMR and MS techniques. The relative and absolute configuration of talarolutin A was determined by X-ray diffraction analysis. A combination of NOESY data and comparisons of ECD spectra were employed to assign the relative and absolute configuration of the other analogs. Talarolutins B–D were tested for cytotoxicity against human prostate carcinoma (PC-3) cell line, antimicrobial activity, and induction of quinone reductase; no notable bioactivity was observed in any assay.

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Datum: 05.05.2016


Elucidation of hypoglycemic action and toxicity studies of insulin-like protein from Costus igneus

Publication date: April 2016
Source:Phytochemistry, Volume 124

Author(s): Manasi R. Hardikar, Mokshada E. Varma, Anjali A. Kulkarni, Prasad P. Kulkarni, Bimba N. Joshi

We have reported earlier, an orally active insulin-like protein (ILP) from Costus igneus having potent hypoglycemic property in STZ-induced diabetic Swiss mice. The blood glucose level was reduced significantly within two hours after feeding ILP orally in an oral glucose tolerance test. The present study elucidates the mechanism underlying the hypoglycemic action of ILP. Mechanism of action of ILP was studied in differentiated L6 myotubes. 2-NBDG uptake stimulated by ILP was studied in differentiated L6 myotubes under normoglycemic, hyperglycemic and induced insulin resistant conditions. ILP treatment significantly increased 2-NBDG uptake in differentiated L6 myotubes. The levels of insulin signaling molecules IRS-1 and GLUT-4 were assessed in ILP treated L6 myotubes by immunoblot analysis of cytoplasmic and plasma membrane fractions respectively. Immunoblot analysis revealed an increase in cytoplasmic IRS-1 with a concomitant increase in GLUT-4 translocation to the plasma membrane in a time dependent manner. Toxicity studies of ILP were performed on normal as well as diabetic Swiss albino mice. ILP did not show any toxicity in the acute and sub-chronic toxicity studies in normal as well as diabetic Swiss albino mice. Mass spectrometry was carried out to identify ILP. MALDI TOF/TOF MS analysis of ILP revealed sequence homology with the predicted protein from Physcomitrella patens. Our study reveals that ILP acts via insulin signaling pathway and can be used as oral insulin mimetic.

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Datum: 05.05.2016


Editorial Board/Publication Information

Publication date: March 2016
Source:Phytochemistry, Volume 123










Datum: 05.05.2016


Phytochemical Society of Europe

Publication date: April 2016
Source:Phytochemistry, Volume 124










Datum: 05.05.2016


Benzoylsalicylic acid isolated from seed coats of Givotia rottleriformis induces systemic acquired resistance in tobacco and Arabidopsis

Publication date: June 2016
Source:Phytochemistry, Volume 126

Author(s): Samuel Kamatham, Kishore Babu Neela, Anil Kumar Pasupulati, Reddanna Pallu, Surya Satyanarayana Singh, Padmaja Gudipalli

Systemic acquired resistance (SAR), a whole plant defense response to a broad spectrum of pathogens, is characterized by a coordinated expression of a large number of defense genes. Plants synthesize a variety of secondary metabolites to protect themselves from the invading microbial pathogens. Several studies have shown that salicylic acid (SA) is a key endogenous component of local and systemic disease resistance in plants. Although SA is a critical signal for SAR, accumulation of endogenous SA levels alone is insufficient to establish SAR. Here, we have identified a new acyl derivative of SA, the benzoylsalicylic acid (BzSA) also known as 2-(benzoyloxy) benzoic acid from the seed coats of Givotia rottleriformis and investigated its role in inducing SAR in tobacco and Arabidopsis. Interestingly, exogenous BzSA treatment induced the expression of NPR1 (Non-expressor of pathogenesis-related gene-1) and pathogenesis related (PR) genes. BzSA enhanced the expression of hypersensitivity related (HSR), mitogen activated protein kinase (MAPK) and WRKY genes in tobacco. Moreover, Arabidopsis NahG plants that were treated with BzSA showed enhanced resistance to tobacco mosaic virus (TMV) as evidenced by reduced leaf necrosis and TMV-coat protein levels in systemic leaves. We, therefore, conclude that BzSA, hitherto unknown natural plant product, is a new SAR inducer in plants.

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Datum: 05.05.2016


Graphical Contents List

Publication date: March 2016
Source:Phytochemistry, Volume 123










Datum: 05.05.2016






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