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.

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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



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: 30.06.2016


Quali-quantitative analysis of the phenolic fraction of the flowers of Corylus avellana, source of the Italian PGI product “Nocciola di Giffoni”: Isolation of antioxidant diarylheptanoids

Publication date: Available online 29 June 2016
Source:Phytochemistry

Author(s): Milena Masullo, Angela Mari, Antonietta Cerulli, Alfredo Bottone, Bogdan Kontek, Beata Olas, Cosimo Pizza, Sonia Piacente

There is only limited information available on the chemical composition of the non-edible parts of Corylus avellana, source of the Italian PGI product “Nocciola di Giffoni” (hazelnut). An initial LC-MS profile of the methanolic extract of the male flowers of C. avellana, cultivar ‘Tonda di Giffoni’ led to the isolation of 12 compounds, of which the structures were elucidated by NMR spectroscopy. These were identified as three previously undescribed diarylheptanoids, named giffonins Q-S, along with nine known compounds. Furthermore, the quantitative determination of the main compounds occurring in the methanolic extract of C. avellana flowers was carried out by an analytical approach based on LC-ESI(QqQ)MS, using the Multiple Reaction Monitoring (MRM) experiment. In order to explore the antioxidant ability of C. avellana flowers, the methanolic extract and the isolated compounds were evaluated for their inhibitory effects on human plasma lipid peroxidation induced by H2O2 and H2O2/Fe2+, by measuring the concentration of TBARS.

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Datum: 30.06.2016


Natural variability in acyl moieties of sugar esters produced by certain tobacco and other Solanaceae species

Publication date: Available online 1 June 2016
Source:Phytochemistry

Author(s): Antoaneta B.M. Kroumova, Dave Zaitlin, George J. Wagner

A unique feature of glandular trichomes of plants in the botanical family Solanaceae is that they produce sugar esters (SE), chemicals that have been shown to possess insecticidal, antifungal, and antibacterial properties. Sugar esters of tobacco (Nicotiana tabacum) provide pest resistance, and are important flavor precursors in oriental tobacco cultivars. Acyl moieties of SEs in Nicotiana spp., petunia, and tomato are shown to vary with respect to carbon length and isomer structure (2–12 carbon chain length; anteiso-, iso-, and straight-chain). Sugar esters and their acyl groups could serve as a model to explore the basis of phenotypic diversity and adaptation to natural and agricultural environments. However, information on the diversity of acyl composition among species, cultivars, and accessions is lacking. Herein, described is the analysis of SE acyl groups found in 21 accessions of Nicotiana obtusifolia (desert tobacco), six of Nicotiana occidentalis subsp. hesperis, three of Nicotiana alata, two of N. occidentalis, four modern tobacco cultivars, five petunia hybrids, and one accession each of a primitive potato (Solanum berthaultii) and tomato (Solanum pennellii). A total of 20 different acyl groups was observed that were represented differently among cultivars, species, and accessions. In Nicotiana species, acetate and iso- and anteiso-branched acids prevailed. Straight-chain groups (2–8 carbons) were prominent in petunias, while octanoic acid was prominent in N. alata and N. × sanderae. Two unexpected acyl groups, 8-methyl nonanoate and decanoate were found in N. occidentalis subsp. hesperis. Longer chain groups were found in the petunia, tomato, and potato species studied.

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Datum: 30.06.2016


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: 30.06.2016


Graphical Contents List

Publication date: August 2016
Source:Phytochemistry, Volume 128










Datum: 30.06.2016


Graphical Contents List

Publication date: July 2016
Source:Phytochemistry, Volume 127










Datum: 30.06.2016


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: 30.06.2016


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: 30.06.2016


Rare phenolic structures found in the aerial parts of Eriosema laurentii De Wild.

Publication date: August 2016
Source:Phytochemistry, Volume 128

Author(s): Sylvin Benjamin Ateba, Dieudonné Njamen, Claus Gatterer, Tamara Scherzer, Martin Zehl, Hanspeter Kählig, Liselotte Krenn

Recent pharmacological and toxicological investigations of Eriosema laurentii (Leguminosae) have underlined the plausibility of the use of this plant in traditional African medicine. A very complex pattern of phenolic compounds was detected in the tested extracts. Based on these preceding results a detailed phytochemical study was performed and resulted in the isolation and identification of eleven compounds. All are reported in this plant for the first time and four of those are previously undescribed secondary metabolites: 3,4′,6,8-tetrahydroxyflavanone-7-C-glucoside and 3,4′,6,8-tetrahydroxyflavone-7-C-glucoside with an extremely rare substitution pattern as well as 1-[2,4-dihydroxy-3-(2-hydroxy-3-methylbut-3-en-1-yl)phenyl]-3-phenylpropan-1-one and 1-[2,4-dihydroxy-3-(2-hydroxy-3-methylbut-3-en-1-yl)phenyl]-3-(4-methoxyphenyl)-propan-1-one. Their structures were elucidated unambiguously by extensive MS- and NMR-experiments.

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Datum: 30.06.2016


Saponins of Agave: Chemistry and bioactivity

Publication date: Available online 30 June 2016
Source:Phytochemistry

Author(s): Jasmeen Sidana, Bikram Singh, Om P. Sharma

The genus Agave comprises more than 400 species with geographical presence in the tropical and sub-tropical regions of the world. These plants have a rich history of folkloric use and are known for a wide spectrum of applications. Secondary metabolites of diverse chemical classes have been reported from Agave species. Owing to their pharmacological significance, the steroidal saponins of Agave have caught the attention of phytochemists, biologists and drug discovery scientists. The present review describes 141 steroidal saponins and sapogenins and covers the literature published from 1970 to 2015. It is a comprehensive and coherent presentation of the structures, methods of chemical profiling, structure elucidation and biological activities of the saponins and sapogenins reported from Agave. The article provides a perspective of the research on steroidal compounds of Agave.

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Datum: 30.06.2016


Identification and characterization of UDP-glucose:Phloretin 4′-O-glycosyltransferase from Malus x domestica Borkh

Publication date: Available online 14 June 2016
Source:Phytochemistry

Author(s): Mosaab Yahyaa, Rachel Davidovich-Rikanati, Yoram Eyal, Alona Sheachter, Sally Marzouk, Efraim Lewinsohn, Mwafaq Ibdah

Apples (Malus x domestica Brokh.) are among the world’s most important food crops with nutritive and medicinal importance. Many of the health beneficial properties of apple fruit are suggested to be due to (poly)phenolic metabolites, including various dihydrochalcones. Although many of the genes and enzymes involved in polyphenol biosynthesis are known in many plant species, the specific reactions that lead to the biosynthesis of the sweet tasting dihydrochalcones, such as trilobatin, are unknown. To identify candidate genes for involvement in the glycosylation of dihydrochalcones, existing genome databases of the Rosaceae were screened for apple genes with significant sequence similarity to Bacillus subtilis phloretin glycosyltransferase. Herein reported is the identification and functional characterization of a Malus x domestica gene encoding phloretin-4′-O-glycosyltransferase designated MdPh-4′-OGT. Recombinant MdPh-4′-OGT protein glycosylates phloretin in the presence of UDP-glucose into trilobatin in vitro. Its apparent K m values for phloretin and UDP-glucose were 26.1 μM and 1.2 mM, respectively. Expression analysis of the MdPh-4′-OGT gene indicated that its transcript levels showed significant variation in apple tissues of different developmental stages.

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Datum: 30.06.2016


Naphthohydroquinones, naphthoquinones, anthraquinones, and a naphthohydroquinone dimer isolated from the aerial parts of Morinda parvifolia and their cytotoxic effects through up-regulation of p53

Publication date: Available online 10 June 2016
Source:Phytochemistry

Author(s): Jie Kang, Peng Zhang, Zengping Gao, Jian Zhang, Zheng Yan, Hongqing Wang, Ruoyun Chen

Five unknown compounds, morindaparvins C–G, consisting of naphthohydroquinones, a naphthoquinone, an anthraquinone, and a naphthohydroquinone dimer, together with three known quinones and seven other known compounds, were isolated from the aerial parts of Morinda parvifolia. The structures of morindaparvins C, D, E, F, and G were elucidated on the basis of spectroscopic or X-ray diffraction analysis as methyl 4-hydroxy-1,6-dimethoxy-naphthalene-2-carboxylate, methyl 4,8-dihydroxy-1-methoxy-naphthalene-2-carboxylate, 3-amino-6-methoxy-2-methoxycarbonyl-1,4-naphthoquinone, 1,4-dihydroxy-7-hydroxymethyl-anthraquinone, and dimethyl 1,1′-dihydroxy-4,4′,7,7′-tetramethoxy-2,2′-binaphthalene-3,3′-dicarboxylate, respectively. Naphthoquinones and naphthohydroquinone dimers were previously unknown in the genus Morinda. In addition, the compounds were tested for cytotoxicity against four human cancer cell lines HeLa, A2780, Ketr3 and MCF-7 and their effects on p53-activated transcription. Three naphthoquinones had moderate cytotoxic effects with IC50 values ranging from 1.51 to 9.56 μM, through up-regulation of p53 transcriptional activity.

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Datum: 30.06.2016


Truncations of xyloglucan xylosyltransferase 2 provide insights into the roles of the N- and C-terminus

Publication date: August 2016
Source:Phytochemistry, Volume 128

Author(s): Alan T. Culbertson, Adrienne L. Smith, Matthew D. Cook, Olga A. Zabotina

Xyloglucan is the most abundant hemicellulose in the primary cell wall of dicotyledonous plants. In Arabidopsis, three xyloglucan xylosyltransferases, XXT1, XXT2, and XXT5, participate in xylosylation of the xyloglucan backbone. Despite the importance of these enzymes, there is a lack of information on their structure and the critical residues required for substrate binding and transferase activity. In this study, the roles of different domains of XX2 in protein expression and catalytic activity were investigated by constructing a series of N- and C-terminal truncations. XXT2 with an N-terminal truncation of 31 amino acids after the predicted transmembrane domain showed the highest protein expression, but truncations of more than 31 residues decreased protein expression and catalytic activity. XXT2 constructs with C-terminal truncations showed increased protein expression but decreased activity, particularly for truncations of 44 or more amino acids. Site-directed mutagenesis was also used to investigate six positively charged residues near the C-terminus and found that four of the mutants showed decreased enzymatic activity. We conclude that the N- and C-termini of XXT2 have important roles in protein folding and enzymatic activity: the stem region (particularly the N-terminus of the catalytic domain) is critical for protein folding and the C-terminus is essential for enzymatic activity but not for protein folding.

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Datum: 30.06.2016


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: 30.06.2016


Carlactone-type strigolactones and their synthetic analogues as inducers of hyphal branching in arbuscular mycorrhizal fungi

Publication date: Available online 2 June 2016
Source:Phytochemistry

Author(s): Narumi Mori, Kenta Nishiuma, Takuya Sugiyama, Hideo Hayashi, Kohki Akiyama

Hyphal branching in the vicinity of host roots is a host recognition response of arbuscular mycorrhizal fungi. This morphological event is elicited by strigolactones. Strigolactones are carotenoid-derived terpenoids that are synthesized from carlactone and its oxidized derivatives. To test the possibility that carlactone and its oxidized derivatives might act as host-derived precolonization signals in arbuscular mycorrhizal symbiosis, carlactone, carlactonoic acid, and methyl carlactonoate as well as monohydroxycarlactones, 4-, 18-, and 19-hydroxycarlactones, were synthesized chemically and evaluated for hyphal branching-inducing activity in germinating spores of the arbuscular mycorrhizal fungus Gigaspora margarita. Hyphal branching activity was found to correlate with the degree of oxidation at C-19 methyl. Carlactone was only weakly active (100 ng/disc), whereas carlactonoic acid showed comparable activity to the natural canonical strigolactones such as strigol and sorgomol (100 pg/disc). Hydroxylation at either C-4 or C-18 did not significantly affect the activity. A series of carlactone analogues, named AD ester and AA’D diester, was synthesized by reacting formyl Meldrum’s acid with benzyl, cyclohexylmethyl, and cyclogeranyl alcohols (the A-ring part), followed by coupling of the potassium enolates of the resulting formylacetic esters with the D-ring butenolide. AD ester analogues exhibited moderate activity (1 ng–100 pg/disc), while AA’D diester analogues having cyclohexylmethyl and cyclogeranyl groups were highly active on the AM fungus (10 pg/disc). These results indicate that the oxidation of methyl to carboxyl at C-19 in carlactone is a prerequisite but BC-ring formation is not essential to show hyphal branching activity comparable to that of canonical strigolactones.

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Datum: 30.06.2016


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: 30.06.2016


Effects of meteorological conditions and plant growth stage on the accumulation of carvacrol and its precursors in Thymus pulegioides

Publication date: August 2016
Source:Phytochemistry, Volume 128

Author(s): Vaida Vaičiulytė, Rita Butkienė, Kristina Ložienė

The effects of meteorological conditions (temperature, rainfall, photosynthetically active solar radiation (PAR) and sunshine duration) and plant growth stages on the quantitative composition of a secondary metabolite – essential oil and its main compounds, in the carvacrol chemotype of Thymus pulegioides L. (Lamiaceae) cultivated in open ground were studied under the same micro-edaphoclimatic environmental conditions for six years. The essential oil was isolated by hydrodistillation, the analysis of monoterpenic phenol carvacrol and the biogenetic precursors (monoterpene hydrocarbons p-cymene and γ-terpinene) were carried out annually using GC-FID and GC-MS. In the carvacrol chemotype investigated in this study, the yield of essential oil varied from 0.72% to 0.98% (CV = 12%) at full flowering stage. Regression analysis showed a significant negative relationship between the amount of essential oil and both temperature and rainfall during T. pulegioides flowering (July) and the period from April (beginning of vegetation) to July, but a strong positive relationship with photosynthetically active solar radiation during April–July (beta = 0.658, p < 0.05). The percentage of carvacrol, p-cymene and γ-terpinene ranged between 16.88 and 29.29% (CV = 18%), 5.54–11.33% (CV = 23%) and 20.60–24.43% (CV = 6%) respectively. Regression analysis showed the significant positive relationship between the percentage of carvacrol and sunshine duration at the flowering stage (in July) (beta = 0.699, p < 0.05); while the negative relationship was established between the percentages of precursors of carvacrol and photosynthetically active solar radiation and sunshine duration. The accumulation of p-cymene, the percentage of which varied most strongly from all investigated chemical compounds, showed significant positive relationships with temperature and rainfall during the period April–July and temperature in July (beta = 0.617, beta = 0.439 and beta = 0.429 respectively, p < 0.05). The analysis of plant growth stages showed that the highest amount of essential oil in carvacrol chemotype of T. pulegioides accumulated at ripening/seed maturity stage. The percentage of carvacrol increased gradually from the stem elongation to the post-flowering/seed maturity stage, overtaking the full flowering stage by 22%. The highest carvacrol content in the T. pulegioides carvacrol chemotype coincided with the highest oil yield during the fruiting stage. The amount of essential oil was also measured at the second full flowering stage, because after cutting the aerial part of the plant at the full flowering stage T. pulegioides often bloom for a second time: the carvacrol chemotype accumulated by 21% lower yield of essential oil at this stage compared to the first flowering, however, only traces of carvacrol and its precursors were found at the second full flowering stage.

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Datum: 30.06.2016


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: 30.06.2016


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: 30.06.2016


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: 30.06.2016


High concentrations of aromatic acylated anthocyanins found in cauline hairs in Plectranthus ciliatus

Publication date: August 2016
Source:Phytochemistry, Volume 128

Author(s): Monica Jordheim, Kate Calcott, Kevin S. Gould, Kevin M. Davies, Kathy E. Schwinn, Øyvind M. Andersen

Vegetative shoots of a naturalized population of purple-leaved plectranthus (Plectranthus ciliatus, Lamiaceae) were found to contain four main anthocyanins: peonidin 3-(6″-caffeoyl-β-glucopyranoside)-5-β-glucopyranoside, peonidin 3-(6″-caffeoyl-β-glucopyranoside)-5-(6‴-malonyl-β-glucopyranoside), peonidin 3-(6″-E-p-coumaroyl-β-glucopyranoside)-5-(6‴-malonyl-β-glucopyranoside), and peonidin 3-(6″-E-p-coumaroyl-β-glucopyranoside)-5-β-glucopyranoside. The first three of these pigments have not been reported previously from any plant. They all follow the typical anthocyanin pattern of Lamiaceae, with universal occurrence of anthocyanidin 3,5-diglucosides and aromatic acylation with p-coumaric and sometimes caffeic acids; however, they differ by being based on peonidin. The four anthocyanins were present in the leaves (22.2 mg g−1 DW), and in the xylem and interfascicular parenchyma of the stem. They were exceptionally abundant, among the highest reported for any plant organ, in epidermal hairs on some of the stem internodes (101 mg g−1 DW). Anthocyanin content in these hairs increased more than three-fold from the youngest to the fourth-youngest internodes. In situ absorbances (λmax ≈ 545 nm) were bathochromic in comparison to absorbances of the isolated anthocyanins in their flavylium form in acidified aqueous solutions (λmax = 525 nm), suggesting that the anthocyanins occur both in quinoidal and flavylium forms in constant proportions in the anthocyanic hair cells. The most distinctive observation with respect to relative proportions of individual anthocyanins was found in de-haired internodes, for which anthocyanin caffeoyl-derivatives decreased, and anthocyanin coumaroyl-derivatives increased, from the youngest to the fourth-youngest internode.

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Datum: 30.06.2016


Chemical constituents from Melicope pteleifolia leaves

Publication date: Available online 30 June 2016
Source:Phytochemistry

Author(s): Ngoc Hieu Nguyen, Thi Kim Quy Ha, Sangho Choi, Sangmi Eum, Chul Ho Lee, Tran The Bach, Vu Tien Chinh, Won Keun Oh

Five acetophenones bearing spiroketal-hexofuranoside rings, one di-C-glycosidic acetophenone and two benzopyrans, along with 16 known compounds were isolated from the leaves of Melicope pteleifolia. Structures of all the isolates were elucidated using extensive spectroscopic methods, including 1D, 2D-NMR and HRESIMS. All the isolates were also evaluated for their neuraminidase inhibitory activities against H1N1, H9N2, wild-type H1N1 and oseltamivir-resistant H1N1 (H274Y mutation) virus strains. Of the isolates, tamarixetin 3-robinobioside was found to exhibit the strongest enzymatic inhibition (IC50 24.93 ± 3.46, 23.19 ± 5.41, 26.67 ± 5.16 and 40.16 ± 4.50 μM, respectively). Selected candidates, kaempferol 3-robinobioside, kaempferol 3-O-β-d-glucopyranosyl (1 → 2)-α-d-xylopyranoside and tamarixetin 3-robinobioside, also showed moderate reductions in H1N1-induced cytopathic effects on MDCK cells.






Datum: 30.06.2016


Editorial Board/Publication Information

Publication date: August 2016
Source:Phytochemistry, Volume 128










Datum: 30.06.2016


Zebiriosides A-L, oleanane saponins from the roots of Dendrobangia boliviana

Publication date: Available online 26 June 2016
Source:Phytochemistry

Author(s): Ilhem Zebiri, Mohamed Haddad, Laurent Duca, Dominique Harakat, Billy Cabanillas, Lucie Paloque, Amandine Scandolera, Michel Sauvain, Elsa Rengifo, Laurence Voutquenne-Nazabadioko

Twelve oleanane saponins, zebiriosides A-L, were isolated from the roots of Dendrobangia boliviana Rusby, together with two known saponins, talunùmoside I and 3-O-β-d-glucuronopyranosyl serjanic acid. These saponins are glycosides of serjanic or phytolaccinic acid. Their structures were established on two basis: first, their spectral data, mainly HR-TOFESIMS, 1D-NMR (1H, 13C, DEPT) and 2D-NMR (1H 1H COSY, TOCSY, HSQC, HMBC, and ROESY), and second by comparison with literature data. These compounds were evaluated for their cytotoxic, antileishmanial and hemolytic activities. No antileishmanial or hemolytic activities were revealed, however zebirioside C and zebirioside I showed cytotoxicity against fibroblasts with IC50 of 6.4 and 5.6 μM, respectively.

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Datum: 30.06.2016


Anthocyanins of the anthers as chemotaxonomic markers in the genus Populus L.. Differentiation between Populus nigra, Populus alba and Populus tremula

Publication date: August 2016
Source:Phytochemistry, Volume 128

Author(s): Cristina Alcalde-Eon, Ignacio García-Estévez, Julián C. Rivas-Gonzalo, David Rodríguez de la Cruz, María Teresa Escribano-Bailón

Three main species of Popululs L. (Salicaceae) have been reported to occur in the Iberian Peninsula: Populus nigra L., Populus alba L. and Populus tremula L. The degree of pilosity of the bracts of the male catkins is a key character for their differentiation. The anthers of these poplar species possess anthocyanins that provide them a red colouration. Since these poplars are wind-pollinated and, consequently, do not need to attract pollinators, anthocyanins in the anthers might be acting as photoprotectors, shielding pollen grains from excessive sunlight. In order to verify this hypothesis, the first objective of this study was to establish if there is any relationship between the degree of pilosity of the bracts (related to the physical shading of the pollen grains) and the levels and types of anthocyanins in the anthers of these three species. This study also aimed to check the usefulness of the anthocyanins of the anthers as chemotaxonomic markers, through the study of the differences in the anthocyanin composition between these poplar species. Anthocyanins were identified from the data supplied by HPLC-DAD-MSn analyses. Seventeen different compounds, including mono-, di- and triglycosides and anthocyanin-derived pigments (F-A+ dimers) have been identified. Cyanidin 3-O-glucoside was the major compound in all the samples (>60% of the total content), which may be in accordance with the photoprotective role proposed for them. However, qualitative and quantitative differences were detected among samples. Cyanidin and delphinidin 3-O-sambubiosides have been detected only in the anthers of P. tremula as well as cyanidin 3-O-(2″-O-xyloxyl)rutinoside, making them valuable chemotaxonomic markers for this species. Hierarchical Cluster and Principal Components Analyses (HCA and PCA) carried out with the anthocyanin percent composition data have allowed a separation of the samples that is in accordance with the initial classification of the samples made from the morphological characters of the specimens. Furthermore, these analyses have revealed intraspecific differences among samples that point out to different clones or varieties of a same species.

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Datum: 30.06.2016


Effect of growth temperature on glucosinolate profiles in Arabidopsis thaliana accessions

Publication date: Available online 16 June 2016
Source:Phytochemistry

Author(s): Ralph Kissen, Franziska Eberl, Per Winge, Eivind Uleberg, Inger Martinussen, Atle M. Bones

Glucosinolates are plant secondary metabolites with important roles in plant defence against pathogens and pests and are also known for their health benefits. Understanding how environmental factors affect the level and composition of glucosinolates is therefore of importance in the perspective of climate change. In this study we analysed glucosinolates in Arabidopsis thaliana accessions when grown at constant standard (21 °C), moderate (15 °C) and low (9 °C) temperatures during three generations. In most of the tested accessions moderate and pronounced chilling temperatures led to higher levels of glucosinolates, especially aliphatic glucosinolates. Which temperature yielded the highest glucosinolate levels was accession-dependent. Transcriptional profiling revealed also accession-specific gene responses, but only a limited correlation between changes in glucosinolate-related gene expression and glucosinolate levels. Different growth temperatures in one generation did not consistently affect glucosinolate composition in subsequent generations, hence a clear transgenerational effect of temperature on glucosinolates was not observed.

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Datum: 30.06.2016


Evolutionary correlations in flavonoid production across flowers and leaves in the Iochrominae (Solanaceae)

Publication date: Available online 10 June 2016
Source:Phytochemistry

Author(s): Andrea E. Berardi, Sherry B. Hildreth, Richard F. Helm, Brenda S.J. Winkel, Stacey D. Smith

Plant reproductive and vegetative tissues often use the same biochemical pathways to produce specialized metabolites. In such cases, selection acting on the synthesis of specific products in a particular tissue could result in correlated changes in other products of the pathway, both in the same tissue and in other tissues. This study examined how changes in floral anthocyanin pigmentation affect the production of other compounds of the flavonoid pathway in flowers and in leaves. Focusing on the Iochrominae, a clade of Solanaceae with a wide range of flower colors, liquid chromatography coupled with mass spectrometry and UV detection was used to profile and quantify the variation in two classes of flavonoids, anthocyanins and flavonols. Purple, red, orange and white-flowered Iochrominae produced all of the six common anthocyanidin types, as well as several classes of flavonols. Differences in anthocyanin and flavonol production were significantly correlated in flowers, particularly with respect to B ring hydroxylation pattern. However, these differences in floral flavonoids were not strongly related to differences in leaf chemistry. Specifically, most species made only flavonols (not anthocyanins) in leaves, and these comprised the two most common flavonols, quercetin and kaempferol, regardless of the color of the flower. These results suggest that shifts in flower color may occur without significant pleiotropic consequences for flavonoid production in vegetative tissues. Similar studies in other systems will be important for testing the generality of this pattern in other groups of flowering plants.

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Datum: 30.06.2016


Current knowledge and future research perspectives on cassava (Manihot esculenta Crantz) chemical defenses: An agroecological view

Publication date: Available online 14 June 2016
Source:Phytochemistry

Author(s): Delia M. Pinto-Zevallos, Martín Pareja, Bianca G. Ambrogi

Cassava (Manihot esculenta Crantz) is one of the most important staple crops worldwide. It constitutes the major source of carbohydrates for millions of low-income people living in rural areas, as well as a cash crop for smallholders in tropical and sub-tropical regions. The Food and Agriculture Organization of the United Nations predicts that cassava plantations will increase and production systems will intensify in the future, highlighting the need for developing strategies that improve the sustainability of production. Plant chemical defenses hold the potential for developing pest management strategies, as these plant traits can influence the behavior and performance of both pests and beneficial arthropods. Cassava plants are well-defended and produce a number of compounds involved in direct defense, such as cyanogenic glycosides, flavonoid glycosides, and hydroxycoumarins. In addition, volatile organic compounds induced upon herbivory and the secretion of extrafloral nectar act as indirect defense against herbivores by recruiting natural enemies. Here, cassava chemical defenses against pest arthropods are reviewed, with the aim of identifying gaps in our knowledge and areas of research that deserve further investigation for developing sound pest control strategies to improve sustainable production of this crop, and how these defenses can be used to benefit other crops. Cyanogenic content in cassava is also highly toxic to humans, and can cause irreversible health problems even at sub-lethal doses when consumed over prolonged periods. Therefore, the promotion of chemical defense in this crop should not aggravate these problems, and must be accompanied with the education on processing methods that reduce human exposure to cyanide.

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Datum: 30.06.2016


A new view on the codonocarpine type alkaloids of Capparis decidua

Publication date: August 2016
Source:Phytochemistry, Volume 128

Author(s): Yvonne Forster, Abdul Ghaffar, Stefan Bienz

Several spermidine alkaloids are described in literature as constituents of the root bark of Capparis decidua. Since some of the proposed structures, however, are in conflict with the expected biosynthetic paths, an extract of the root bark of the plant was re-investigated. Four major spermidine alkaloids of the codonocarpine type were identified and their structures elucidated: of the four compounds, isocodonocarpine was described previously for C. decidua and cadabicine was proposed as a possible constituent as well. Codonocarpine was found for the first time in an extract of C. decidua but was previously isolated from a closely related plant. Capparidisinine, finally, is an alkaloid with a structure that has never been described before. The structures of the four alkaloids are substantiated by NMR and MS data, and the four compounds are in logical agreement with biosynthetic considerations: they would arise from α,ω-bis-adducts of spermidine with coumaric and/or ferulic acids, followed by phenol oxidation.

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Datum: 30.06.2016


Abietane-type diterpenoids from the roots of Caryopteris mongolica and their cholinesterase inhibitory activities

Publication date: Available online 10 June 2016
Source:Phytochemistry

Author(s): Toshihiro Murata, Yoshinobu Ishikawa, Erdenebileg Saruul, Erdenechimeg Selenge, Kenroh Sasaki, Kaoru Umehara, Fumihiko Yoshizaki, Javzan Batkhuu

Eleven abietane-type diterpenoids and two known abietanes were isolated from the roots of Caryopteris mongolica, and their structures were characterized. The absolute configurations at C-5 and C-10 were determined from the NMR data, including from the nuclear Overhauser effect and CD spectra, and the absolute configuration of C-16 in the hydroxypropyl group was determined via a modified Mosher’s method. Furthermore, the previously unknown absolute configuration of the C-15 of cyrtophyllone B was determined to be in an R-configuration using X-ray crystallography. To estimate the preventive effects of the isolates for neurodegenerative disease development, their inhibitory activities against acetylcholinesterase (AChE) from human erythrocytes and butyrylcholinesterase (BChE) from horse serum were evaluated.

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Datum: 30.06.2016


Effect of salinity on the fatty acid and triacylglycerol composition of five haptophyte algae from the genera Coccolithophora, Isochrysis and Prymnesium determined by LC-MS/APCI

Publication date: Available online 10 June 2016
Source:Phytochemistry

Author(s): Linda Nedbalová, Antonín Střížek, Karel Sigler, Tomáš Řezanka

Non-aqueous reversed-phase high-performance liquid chromatography (NARP-HPLC) with atmospheric pressure chemical ionization (APCI) was used for separation of triacylglycerols from five strains of haptophyte algae (genera Coccolithophora, Isochrysis, and Prymnesium). This study describes the separation and identification of C18 polyunsaturated triacylglycerols containing stearidonic and octadecapentaenoic fatty acids, including their regioisomers. Salinity affects the proportion of saturated and unsaturated fatty acids. The biosynthesis of C18 polyunsaturated triacylglycerols was found to be very stereospecific and to depend on the salinity of cultivation media, asymmetric regioisomers predominating at low salinity (sn-OpOpSt and/or PoStSt) and symmetric ones at high salinity (sn-OpStOp and or StPoSt).

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Datum: 30.06.2016


Bioactive ent-kaurane diterpenoids from Isodon serra

Publication date: Available online 10 June 2016
Source:Phytochemistry

Author(s): Jun Wan, Miao Liu, Hua-Yi Jiang, Jin Yang, Xue Du, Xiao-Nian Li, Wei-Guang Wang, Yan Li, Jian-Xin Pu, Han-Dong Sun

Nine 7,20-epoxy-ent-kaurane diterpenoids (15-acetylmegathyrin B, serrin E, 14β-hydroxyrabdocoestin A, serrin F, serrin G, 11-epi-rabdocoestin A, serrin H, serrin I, and 15-acetylenanderianin N), along with seven known ones, were isolated from the aerial parts of Isodon serra. Their structures were elucidated by extensive spectroscopic analysis, and the absolute configuration of 15-acetylmegathyrin B was determined by signal-crystal X-ray diffraction. All of these compounds were evaluated for their cytotoxic activities against five human tumor cell lines (HL-60, SMMC-7721, A-549, MCF-7, SW480). Serrin F, rabdocoestin B and 1α,11β-dihydroxy-1α,11β-acetonide-7α,20-epoxy-ent-kaur-16-en-15-one showed cytotoxic activities against all cell lines, with IC50 values ranging from 0.7 to 4.6 μM; serrin F also strongly inhibited NO production in LPS-stimulated RAW264.7 cells. Otherwise, 14β-hydroxyrabdocoestin A, serrins H and I, as well as enanderianin N and megathyrin B, also exhibited inhibitory effects towards NO production, while no cytotoxicity against five cell lines was detected.

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Datum: 30.06.2016


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

Publication date: August 2016
Source:Phytochemistry, Volume 128

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: 30.06.2016


Hepatoprotective pyranocoumarins from the stems of Clausena emarginata

Publication date: Available online 8 June 2016
Source:Phytochemistry

Author(s): Hong-Min Xia, Chuang-Jun Li, Jing-Zhi Yang, Jie Ma, Yan Li, Li Li, Dong-Ming Zhang

Seven pyranocoumarins, clauemarmarins A−G, along with 6 known analogues were isolated from the stems of Clausena emarginata. Their structures were elucidated by extensive spectroscopic analyses, and the absolute stereochemistries at C-6″ of clauemarmarin B, C and D and the absolute configurations of clauemarmarin E, F and G were determined by ECD experiments. Compounds clauemarmarin C, D and two known analogues exhibited hepatoprotective activities against DL-galactosamine-induced damage in WB-F344 cells at the concentration of 10 μM.

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Datum: 30.06.2016


Editorial Board/Publication Information

Publication date: June 2016
Source:Phytochemistry, Volume 126










Datum: 30.06.2016


Composition of cuticular waxes coating flag leaf blades and peduncles of Triticum aestivum cv. Bethlehem

Publication date: Available online 2 June 2016
Source:Phytochemistry

Author(s): Radu C. Racovita, Shelly Hen-Avivi, Josefina-Patricia Fernandez-Moreno, Antonio Granell, Asaph Aharoni, Reinhard Jetter

The work herein presents comprehensive analyses of the cuticular wax mixtures covering the flag leaf blade and peduncle of bread wheat (Triticum aestivum) cv. Bethlehem. Overall, Gas Chromatography-Mass Spectrometry and Flame Ionization Detection revealed a wax coverage of flag leaf blades (16 μg/cm2) a third that of peduncles (49 μg/cm2). Flag leaf blade wax was dominated by 1-alkanols, while peduncle wax contained primarily β-diketone and hydroxy-β-diketones, thus suggesting differential regulation of the acyl reduction and β-diketone biosynthetic pathways in the two analyzed organs. The characteristic chain length distributions of the various wax compound classes are discussed in light of their individual biosynthetic pathways and biosynthetic relationships between classes. Along with previously reported wheat wax compound classes (fatty acids, 1-alkanols, 1-alkanol esters, aldehydes, alkanes, β-diketone, hydroxy-β-diketones, alkylresorcinols and methyl alkylresorcinols), esters of 2-alkanols and three types of aromatic esters (benzyl, phenethyl and p-hydroxyphenethyl) are also reported. In particular, 2-heptanol esters were identified. Detailed analyses of the isomer distributions within 1-alkanol and 2-alkanol ester homologs revealed distinct patterns of esterified acids and alcohols, suggesting several wax ester synthases with very different substrate preferences in both wheat organs. Terpenoids, including two terpenoid esters, were present only in peduncle wax.

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Datum: 30.06.2016


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

Publication date: August 2016
Source:Phytochemistry, Volume 128

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. Léonard (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: 30.06.2016


Graphical Contents List

Publication date: June 2016
Source:Phytochemistry, Volume 126










Datum: 30.06.2016


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: 30.06.2016


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: 30.06.2016


Isolation and characterisation of 13 pterosins and pterosides from bracken (Pteridium aquilinum (L.) Kuhn) rhizome

Publication date: August 2016
Source:Phytochemistry, Volume 128

Author(s): Rizgar Hassan Mohammad, Mohammad Nur-e-Alam, Martina Lahmann, Ifat Parveen, Graham J. Tizzard, Simon J. Coles, Mark Fowler, Alex F. Drake, Derren Heyes, Vera Thoss

Systematic phytochemical investigations of the underground rhizome of Pteridium aquilinum (L.) Kuhn (Dennstaedtiaceae) afforded thirty-five pterosins and pterosides. By detailed analysis of one- and two-dimensional nuclear magnetic resonance spectroscopy, circular dichroism (CD) and high-resolution mass spectrometric data, thirteen previously undescribed pterosins and pterosides have been identified. Interestingly, for the first time 12-O-β-D-glucopyranoside substituted pterosins, rhedynosides C and D, and the sulfate-containing pterosin, rhedynosin H, alongside the two known compounds, histiopterosin A and (2S)-pteroside A2, were isolated from the rhizomes of subsp. aquilinum of bracken. In addition, six-membered cyclic ether pterosins and pterosides, rhedynosin A and rhedynoside A, are the first examples of this type of pterosin-sesquiterpenoid. Additionally, the three previously reported compounds (rhedynosin I, (2S)-2-hydroxymethylpterosin E and (2S)-12-hydroxypterosin A) were obtained for the first time from plants as opposed to mammalian metabolic products. Single crystal X-ray diffraction analysis was applied to the previously undescribed compounds (2R)-rhedynoside B, (2R)-pteroside B and (2S)-pteroside K, yielding the first crystal structures for pterosides, and three known pterosins, (2S)-pterosin A, trans-pterosin C and cis-pterosin C. Rhedynosin C is the only example of the cyclic lactone pterosins with a keto group at position C-14. Six selected pterosins ((2S)-pterosin A, (2R)-pterosin B and trans-pterosin C) and associated glycosides ((2S)-pteroside A, (2R)-pteroside B and pteroside Z) were assessed for their anti-diabetic activity using an intestinal glucose uptake assay; all were found to be inactive at 300 μM.

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Datum: 30.06.2016


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: 30.06.2016


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: 30.06.2016


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: 30.06.2016


Phenylbenzoisoquinolindione alkaloids accumulate in stamens of Xiphidium caeruleum Aubl. flowers

Publication date: August 2016
Source:Phytochemistry, Volume 128

Author(s): Yu Chen, Christian Paetz, Riya C. Menezes, Bernd Schneider

Xiphidium caeruleum (Haemodoraceae) flower organs such as carpels, pedicels, petals, and stamens were separately investigated for their phytochemical profile. The stamens appeared to be a rich source of previously undescribed phenylbenzoisoquinolindiones, a group of phenylphenalenone-derived alkaloids, also named aza-phenylphenalenones. Nine previously undescribed compounds with an identical aza-phenylphenalenone core structure but different amino acid-derived side chains at position 2 were isolated and their structures elucidated by nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS). In addition, some previously reported phenylbenzoisoquinolindiones, phenylbenzoisochromenones and flavonoids were found in stamens and other parts of the flowers. The specific occurrence of heterocyclic phenylphenalenone-type compounds in X. caeruleum suggests these are involved in physiological or ecological processes.

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Datum: 30.06.2016


Phytochemical Society of Europe

Publication date: June 2016
Source:Phytochemistry, Volume 126










Datum: 30.06.2016


Chemical characterization of high-molar-mass fractions in a Norway spruce knotwood ethanol extract

Publication date: Available online 30 May 2016
Source:Phytochemistry

Author(s): Annika I. Smeds, Patrik C. Eklund, Stefan M. Willför

The low-molar-mass (LMM) fraction, only, i.e., the GC-eluting compounds, which are mainly lignans, has been characterized in Norway spruce knotwood hydrophilic extracts previously. Of this fraction, many lignans and sesquilignans and all GC peaks supposedly representing dilignans remain unidentified. In this work, dilignans and the GC non-eluting compounds (the high-molar mass fractions, HMM) were characterized in a 7-hydroxymatairesinol-reduced knotwood ethanol extract of Norway spruce by using several fractionation and analytical techniques. A methyl tert-butyl ether (MTBE) insoluble fraction of the extract contained mainly HMM material, of which the main part was shown to consist of lignan oligomers. The oligolignans (with a molar mass up to approximately 3700 Da) seemed to be linked by 55′ bonds, some of them containing one or two guaiacylglycerol ether units linked to the lignan by βO4 or β5 bonds. Several oligolignans were identified or tentatively identified. The MTBE soluble fraction, which accounted for the major part (81%) of the extract, contained mainly LMM material (lignans, sesqui- and dilignans). The part of the HMM material in the MTBE soluble fraction that was easily isolable (2%) seemed to contain polymers of fatty acids and alcohols, resin acids, and sterols.

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Datum: 30.06.2016


Cytotoxic triterpenoid saponins from Clematis tangutica

Publication date: Available online 1 June 2016
Source:Phytochemistry

Author(s): Min Zhao, Zhuo-Ma Da-Wa, Da-Le Guo, Dong-Mei Fang, Xiao-Zhen Chen, Hong-Xi Xu, Yu-Cheng Gu, Bing Xia, Lei Chen, Li-Sheng Ding, Yan Zhou

Eight previously undescribed oleanane-type triterpenoid saponins, clematangoticosides A-H, together with eight known saponins, were isolated from the whole plants of Clematis tangutica (Maxim.) Korsh. Their structures were elucidated by extensive spectroscopic analysis, in combination with chemical methods (acid hydrolysis and mild alkaline hydrolysis). Clematangoticosides D-G were found to be unusual 23, 28-bidesmosidic glycosides. The cytotoxic activities of all of the isolated saponins were evaluated against the four human cancer cell lines SGC-7901, HepG2, HL-60 and U251MG. Clematoside S, sapindoside B, kalopanax saponin A, and koelreuteria saponin A exhibited cytotoxicity against all of the test cancer cell lines with IC50 values in the range of 1.88–27.20 μM, while clematangoticoside D and F showed selective cytotoxicity against SGC-7901 with IC50 values of 24.22 and 21.35 μM, respectively.

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Datum: 30.06.2016


Editorial Board/Publication Information

Publication date: July 2016
Source:Phytochemistry, Volume 127










Datum: 30.06.2016


Botanical and biological pesticides elicit a similar Induced Systemic Response in tomato (Solanum lycopersicum) secondary metabolism

Publication date: Available online 29 May 2016
Source:Phytochemistry

Author(s): Luca Pretali, Letizia Bernardo, Timothy S. Butterfield, Marco Trevisan, Luigi Lucini

Natural pesticides have attracted substantial interest due to the increase in organic agriculture and enhanced attention to environmental pollution. Plant Growth Promoting Bacteria (PGPB) are applied for both disease control and growth enhancement; PGPBs are known to elicit Induced Systemic Response (ISR) in plants. However, less is known about the effect of botanical pesticides, such as the azadirachtin-containing neem extracts, on plant metabolism. This study aimed to investigate the effects of foliar application of the above-mentioned natural pesticides on the metabolic profiling of tomato. Leaf application of Bacillus subtilis fostered Induced Systemic Resistance (ISR) in treated plants via the Jasmonic acid pathway, and enhanced production of secondary metabolites such as flavonoids, phytoalexins and auxins. Changes in sterols and terpenes, as well as an increase in glucosinolates were also observed. Interestingly, azadirachtin-treated tomatoes also showed an increase in ISR and our results revealed that most of the enriched metabolites are shared with a B. subtilis treatment, suggesting conserved biochemical responses. These (un)expected findings indicate that plants are not insensitive to application of natural pesticide and while Azadirachtin is applied as a direct pesticide, it also stimulates a defense response in tomatoes very similar to B. subtilis induced ISR.

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Datum: 30.06.2016






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