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Phytochemistry - Current Research Articles



Current research articles: Phytochemistry

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Phytochemistry - published by Elsevier

Phytochemistry is the international journal of pure and applied plant chemistry, plant biochemistry and molecular biology.




Current articles of the journal:



Identification and characterisation of the phenolics of Ilex glabra L. Gray (Aquifoliaceae) leaves by liquid chromatography tandem mass spectrometry

Publication date: October 2014
Source:Phytochemistry, Volume 106

Author(s): Rakesh Jaiswal , Elias A. Halabi , Mohamed Gamaleldin Elsadig Karar , Nikolai Kuhnert

The phenolics of the leaves of Ilex glabra L. Gray (Aquifoliaceae) were investigated qualitatively by LC–MS n . Thirty-two phenolics were detected and characterised on the basis of their unique fragmentation pattern in the negative ion mode tandem MS spectra. All of them were extracted for the first time from this source and fifteen of them were not reported previously in nature. For the positive identification of phenolic glucosides by LC–MS n a series of authentic standards and experiments were carried out. This is the first report of a full characterisation of 3,4-dihydroxybenzoyl glucosides, 3,4-dihydroxybenzyl glucosides, 4-hydroxybenzoyl glucosides, chlorogenic acid glucosides and vanillic acid glucosides by LC–MS2?4.

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Highlights

We have developed an LC–MS n method for the identification and characterisation of 3,4-dihydroxybenzyl alcohol, 4-hydroxybenzyl alcohol and chlorogenic acid glucosides from Ilex glabra L. Gray leaves.





Posted on 16 September 2014 | 12:54 pm


Announcement for the Phytochemical Society of Europe (PSE)

Publication date: October 2014
Source:Phytochemistry, Volume 106









Posted on 16 September 2014 | 12:54 pm


Elaeodendron orientale as a source of cytotoxic cardenolides

Publication date: September 2014
Source:Phytochemistry, Volume 105

Author(s): Alex A. Osorio , Manuel R. López , Ignacio A. Jiménez , Laila M. Moujir , Matías L. Rodríguez , Isabel L. Bazzocchi

In the present study, we report six cardiac glycosides (16) along with four known ones (710) isolated from the leaves and fruits of Elaeodendron orientale. Their stereostructures were elucidated on the basis of spectroscopic analysis, including 1D and 2D NMR, and the absolute configuration of 1 was determined by X-ray diffraction analysis. The compounds were evaluated for growth inhibitory activity against a panel of human cancer cell lines, HeLa, A-549, MCF-7 and HL-60, and normal Vero cells. Four compounds from this series (5 and 79, IC50 values ranging from 0.01 to 0.07?M) exhibited cytotoxicity against three of the cancer cell lines assayed that was similar to or higher than the well-known therapies digoxin and digitoxigenin. Taking into account the narrow safety range of cardiac glycosides used in clinic, this series shows a selectivity index higher than 3 for three of the cancer cell lines assayed, increasing their interest for further study.

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Posted on 16 September 2014 | 12:54 pm


Glucosinolate profile and distribution among plant tissues and phenological stages of field-grown horseradish

Publication date: October 2014
Source:Phytochemistry, Volume 106

Author(s): Rosa Agneta , Filomena Lelario , Susanna De Maria , Christian Möllers , Sabino Aurelio Bufo , Anna Rita Rivelli

Profile and distribution of glucosinolates (GLS) were detected in plant tissues of horseradish at different developmental stages: beginning of vegetative re-growth, flowering and silique formation. The GLS profile varied widely in the different tissues: we identified 17 GLS in roots and sprouts, one of which was not previously characterized in horseradish, i.e. the 2(S)-hydroxy-2-phenylethyl-GLS (glucobarbarin) and/or 2(R)-hydroxy-2-phenylethyl-GLS (epiglucobarbarin), 11 already found in the roots, including the putative 2-methylsulfonyl-oxo-ethyl-GLS, and 5 previously recognized only in the sprouts. Fifteen of those GLS were also identified in young and cauline leaves, 12 in the mature leaves and 13 in the inflorescences. No difference in GLS profile was observed in plant among the phenological stages. Differences in concentrations of GLS, quantified as desulfated, were found in plant. At the beginning of vegetative re-growth, sprouts while showing the same profile of the roots were much richer in GLS having the highest total GLS concentrations (117.5 and 7.7?molg?1 dry weight in sprouts and roots, respectively). During flowering and silique forming stages, the roots still maintained lower amount of total GLS (7.4?molg?1 of dry weight, on average) with respect to the epigeous tissues, in which mature and young leaves showed the highest total concentrations (70.5 and 73.8?molg?1 of dry weight on average, respectively). Regardless of the phenological stages, the aliphatic GLS were always predominant in all tissues (95%) followed by indolic (2.6%) and benzenic (2.4%) GLS. Sinigrin contributed more than 90% of the total GLS concentration. Aliphatic GLS concentrations were much higher in the epigeous tissues, particularly in the mature and young leaves, while benzenic and indolic GLS concentrations were higher in the roots. Through the phenological stages, GLS concentration increased in young and mature leaves and decreased in cauline leaves and inflorescences, while it remained constant over time in roots.

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Highlights

Identification and quantification of glucosinolates (GLS) were performed in plant tissues during different developmental stages of horseradish (Armoracia rusticana). Overall, 17 GLS were identified, some tentatively assigned, one of which (glucobarbarin and/or epiglucobarbarin) was not previously reported in horseradish plant.





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Graphical Contents List

Publication date: October 2014
Source:Phytochemistry, Volume 106









Posted on 16 September 2014 | 12:54 pm


Antioxidant and anti-inflammatory caffeoyl phenylpropanoid and secoiridoid glycosides from Jasminum nervosum stems, a Chinese folk medicine

Publication date: October 2014
Source:Phytochemistry, Volume 106

Author(s): Zhi-yong Guo , Ping Li , Wen Huang , Jian-jun Wang , Yu-jing Liu , Bo Liu , Ye-ling Wang , Shi-Biao Wu , Edward J. Kennelly , Chun-lin Long

Eight compounds including four caffeoyl phenylpropanoid glycosides, jasnervosides A–D (14), one monoterpenoid glycoside, jasnervoside E (5), and three secoiridoid glycosides, jasnervosides F–H (1012), were isolated from the stems of Jasminum nervosum Lour. (Oleaceae), along with four known compounds, poliumoside (6), verbascoside (7), ?-l-rhamnopyranosyl-(1?3)-O-(?-l-rhamnopyranosyl(1?6)-1-O-E-caffeoyl-?-d-glucopyranoside (8), and jaspolyanthoside (9). Their structures were elucidated on the basis of their physicochemical and spectroscopic properties. Compounds 1, 2, 4 and 11 displayed potent antioxidant activities in the DPPH assay, while 2 and 3 displayed good activities against LPS-induced TNF-? and IL-1? production in BV2 cells. Compounds 15 and 1012 were evaluated for their cytotoxic activities against three human cancer cell lines (A-549, Bel-7402, and HCT-8), but none displayed significant activity.

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Posted on 16 September 2014 | 12:54 pm


Editorial Board/Publication Information

Publication date: September 2014
Source:Phytochemistry, Volume 105









Posted on 16 September 2014 | 12:54 pm


Diterpenes and phenolic compounds from Sideritis pullulans

Publication date: October 2014
Source:Phytochemistry, Volume 106

Author(s): Laura Faiella , Fabrizio Dal Piaz , Ammar Bader , Alessandra Braca

Phytochemical investigation of Sideritis pullulans aerial part and root extracts allowed to isolate six ent-kaurane diterpenes, two phenylpropanoids, and one coumarin, identified as 1?,3?,7?,18-tetrahydroxy-ent-kaur-16-ene (sideripullol A) (1), 3?,11?,18-trihydroxy-ent-kaur-16-ene (sideripullol B) (2), 3?,7?,18-trihydroxy-17-nor-ent-kauran-16-one (sideritone A) (3), 3?,7?-dihydroxy-18-acetyloxy-17-nor-ent-kauran-16-one (sideritone B) (4), 3?,7?,16?,17-tetrahydroxy-18-acetyloxy-ent-kaurane (sideripullol C) (5), 7?,16?,17,18-tetrahydroxy-ent-kaurane (sideripullol D) (6), ?-(3-methoxy-4-hydroxyphenyl)-ethyl-O-?-l-arabinopiranosyl-(1?2)-?-l-rhamnopyranosyl-(1?3)-6-O-t-feruloyl-?-d-glucopyranoside (sideritiside A) (7), ?-(3,4-dihydroxyphenyl)-ethyl-O-?-l-arabinopiranosyl-(1?2)-?-l-rhamnopyranosyl-(1?3)-6-O-t-feruloyl-?-d-glucopyranoside (sideritiside B) (8), and 7-demethyl-8-methoxycoumarsabin (9), respectively. Twenty known compounds, including phenolics, flavonol glycosides, iridoids, diterpenes, sesquiterpenes, lignans, coumarins, and phenylpropanoids were also isolated and characterized. All diterpenes were evaluated for their cytotoxic activity.

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Posted on 16 September 2014 | 12:54 pm


Saponins in the genus Panax L. (Araliaceae): A systematic review of their chemical diversity

Publication date: October 2014
Source:Phytochemistry, Volume 106

Author(s): Wen-zhi Yang , Ying Hu , Wan-ying Wu , Min Ye , De-an Guo

The Panax genus is a crucial source of natural medicines that has benefited human health for a long time. Three valuable medicinal herbs, namely Panax ginseng, Panax quinquefolius, and Panax notoginseng, have received considerable interest due to their extensive application in clinical therapy, healthcare products, and as foods and food additives world-wide. Panax species are known to contain abundant levels of saponins, also dubbed ginsenosides, which refer to a series of dammarane or oleanane type triterpenoid glycosides. These saponins exhibit modulatory effects to the central nervous system and beneficial effects to patients suffering from cardiovascular diseases, and also have anti-diabetic and anti-tumor properties. To the end of 2012, at least 289 saponins were reported from eleven different Panax species. This comprehensive review describes the advances in the phytochemistry of the genus Panax for the period 1963–2012, based on the 134 cited references. The reported saponins can be classified into protopanaxadiol, protopanaxatriol, octillol, oleanolic acid, C17 side-chain varied, and miscellaneous subtypes, according to structural differences in sapogenins. The investigational history of Panax is also reviewed, with special attention being paid to the structural features of the six different subtypes, together with their 1H and 13C NMR spectroscopic characteristics which are useful for determining their structures and absolute configuration.

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Posted on 16 September 2014 | 12:54 pm


Pregnane-type steroidal glycosides from Gymnema griffithii Craib.

Publication date: October 2014
Source:Phytochemistry, Volume 106

Author(s): Suphongphan Srisurichan , Songchan Puthong , Surachai Pornpakakul

Eight pregnane-type steroidal glycosides substituted with ortho-acetate groups were isolated from the methanolic extract of the pericarp of Gymnema griffithii fruits, and named gymnemogriffithosides A–H. Their structures were determined by spectroscopic analysis (one and two dimensional nuclear magnetic resonance, high resolution electrospray ionization mass spectrometry and attenuated total reflectance-Fourier transformed infrared spectroscopy), while the absolute structure of the steroidal skeleton of one of these was additionally determined using Mosher’s method. All compounds were evaluated for their in vitro (i) cytotoxic effects against five human tumor cell lines (BT 474, Chago, Hep-G2, KATO-III and SW620) and (ii) ?-glucosidase inhibitory activity.

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Posted on 16 September 2014 | 12:54 pm


Effect of light, methyl jasmonate and cyclodextrin on production of phenolic compounds in hairy root cultures of Scutellaria lateriflora

Publication date: Available online 15 September 2014
Source:Phytochemistry

Author(s): Zachary Marsh , Tianhong Yang , Luis Nopo-Olazabal , Shuchi Wu , Taylor Ingle , Nirmal Joshee , Fabricio Medina-Bolivar

Scutellaria lateriflora (American skullcap) has been used in traditional medicine to treat several medical conditions including nervous disorders and cancer. Previous studies have associated these medicinal properties to flavones present in roots and leaves of this species. In order to develop a production system and study the biosynthesis of these bioactive compounds, hairy root cultures of S. lateriflora were established and line 4 was selected for further studies based on its growth performance in a modified Murashige and Skoog’s medium supplemented with 0.5mg/l indole-3-butyric acid. Scanning electron microscopy of the hairy roots showed a high profusion of hairs along the root. Several phenolic compounds, including verbascoside, and the flavones wogonin, baicalein, scutellarein and their respective glucuronides were identified by high performance liquid chromatography–tandem mass spectrometry in the root tissue, but not in the culture medium. Among these compounds, verbascoside accumulated at the highest levels. Interestingly, cultures incubated under continuous light and treated with 15mM methyl-?-cyclodextrin for 24h produced significantly higher levels of the aglycones, baicalein and wogonin, but not scutellarein, compared to cultures incubated under continuous darkness. This work demonstrates that hairy root cultures of S. lateriflora have the biosynthetic capacity to produce known Scutellaria flavones and suggest that light may have a selected regulatory effect on the synthesis or accumulation of these phenolic compounds.

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Occurrence of polyamines in root nodules of Phaseolus vulgaris in symbiosis with Rhizobium tropici in response to salt stress

Publication date: Available online 11 September 2014
Source:Phytochemistry

Author(s): Miguel López-Gómez , Libertad Cobos-Porras , Javier Hidalgo-Castellanos , Carmen Lluch

Polyamines (PAs) are low molecular weight aliphatic compounds that have been shown to be an important part of plant responses to salt stress. For that reason in this work we have investigated the involvement of PAs in the response to salt stress in root nodules of Phaseolus vulgaris in symbiosis with Rhizobium tropici. The level and variety of PAs was higher in nodules, compared to leaves and roots, and in addition to the common PAs (putrescine, spermidine and spermine) we found homospermidine (Homspd) as the most abundant polyamine in nodules. UPLC-mass spectrometry analysis revealed the presence of 4-aminobutylcadaverine (4-ABcad), only described in nodules of Vigna angularis before. Indeed, the analysis of different nodular fractions revealed higher level of 4-ABcad, as well as Homspd, in bacteroids which indicate the production of these PAs by the bacteria in symbiosis. The genes involved in PAs biosynthesis in nodules displayed an induction under salt stress conditions which was not consistent with the decline of free PAs levels, probably due to the nitrogen limitations provoked by the nitrogenase activity depletion and/or the conversion of free PAs to theirs soluble conjugated forms, that seems to be one of the mechanisms involved in the regulation of PAs levels. On the contrary, cadaverine (Cad) and 4-ABcad concentrations augmented by the salinity, which might be due to their involvement in the response of bacteroids to hyper-osmotic conditions. In conclusion, the results shown in this work suggest the alteration of the bacteroidal metabolism towards the production of uncommon PAs such as 4-ABcad in the response to salt stress in legume root nodules.

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Analyses of flooding tolerance of soybean varieties at emergence and varietal differences in their proteomes

Publication date: October 2014
Source:Phytochemistry, Volume 106

Author(s): Yohei Nanjo , Hee-Young Jang , Hong-Sig Kim , Susumu Hiraga , Sun-Hee Woo , Setsuko Komatsu

Flooding of fields due to heavy and/or continuous rainfall influences soybean production. To identify soybean varieties with flooding tolerance at the seedling emergence stage, 128 soybean varieties were evaluated using a flooding tolerance index, which is based on plant survival rates, the lack of apparent damage and lateral root development, and post-flooding radicle elongation rate. The soybean varieties were ranked according to their flooding tolerance index, and it was found that the tolerance levels of soybean varieties exhibit a continuum of differences between varieties. Subsequently, tolerant, moderately tolerant and sensitive varieties were selected and subjected to comparative proteomic analysis to clarify the tolerance mechanism. Proteomic analysis of the radicles, combined with correlation analysis, showed that the ratios of RNA binding/processing related proteins and flooding stress indicator proteins were significantly correlated with flooding tolerance index. The RNA binding/processing related proteins were positively correlated in untreated soybeans, whereas flooding stress indicator proteins were negatively correlated in flooded soybeans. These results suggest that flooding tolerance is regulated by mechanisms through multiple factors and is associated with abundance levels of the identified proteins.

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Posted on 16 September 2014 | 12:54 pm


Thiophene acetylenes and furanosesquiterpenes from Xanthopappus subacaulis and their antibacterial activities

Publication date: October 2014
Source:Phytochemistry, Volume 106

Author(s): Li Zhang , Chao-Jun Chen , Jia Chen , Qian-Qian Zhao , Ya Li , Kun Gao

In a search for naturally occurring antibacterial compounds in medicinal plants, six hitherto unknown thiophene acetylenes, named 10,11-threo-xanthopappin D, 10,11-erythro-xanthopappin D, 10,11-cis-xanthopappin B, 5-(but-4-chloro-3-hydroxy-1-ynyl)-2-(Z)-pent-3-ene-1-ynylthiophene, 5-(but-4-chloro-3-hydroxy-1-ynyl)-2-(E)-pent-3-ene-1-ynylthiophene, 5-(but-3,4-dihydroxy-1-ynyl)-2-(Z)-pent-3-ene-1-ynylthiophene and two furanosesquiterpenes, as well as fifteen known compounds, were isolated from Xanthopappus subacaulis, which has been used as a traditional Tibetan medicine in China. A biosynthetic pathway to thiophene acetylenes was proposed and, the isolated compounds were tested for their antibacterial activity against five bacteria. Within the series of thiophene acetylenes tested, 10,11-threo-xanthopappin D with a threo configuration exhibited strong activity against Bacillus subtilis, with a minimum inhibitory concentration (MIC) of 7.25?g/mL, whereas 10,11-erythro-xanthopappin D with erythro configuration possessed broad-spectrum antibacterial activity against Escherichia coli, Bacillus cereus, Staphylococcus aureus and Erwinia carotovora, with MICs of 12.5, 15.5, 7.25 and 7.25?g/mL, respectively. Meanwhile, the compounds 10,11-cis-xanthopappin B, xanthopappin B, 5-(but-4-chloro-3-hydroxy-1-ynyl)-2-(Z)-pent-3-ene-1-ynylthiophene and 5-(but-4-chloro-3-hydroxy-1-ynyl)-2-(E)-pent-3-ene-1-ynylthiophene substituted with a Cl atom at C-14 showed moderate inhibitory activity against E. coli, B. cereus, S. aureus, E. carotovora and B. subtilis, with MICs ranging from 31.25 to 62.5?g/mL. The structures of these compounds were elucidated through the comprehensive analysis of spectroscopic data, including UV, IR, MS and NMR.

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Posted on 16 September 2014 | 12:54 pm


A reproducible analytical system based on the multi-component analysis of triterpene acids in Ganoderma lucidum

Publication date: Available online 8 September 2014
Source:Phytochemistry

Author(s): Juan Da , Chun-Ru Cheng , Shuai Yao , Hua-Li Long , Yan-Hong Wang , Ikhlas A. Khan , Yi-Feng Li , Qiu-Rong Wang , Lu-Ying Cai , Bao-Hong Jiang , Xuan Liu , Wan-Ying Wu , De-An Guo

Ultra-performance liquid chromatography (UPLC) and Single Standard for Determination of Multi-Components (SSDMC) are becoming increasingly important for quality control of medicinal herbs; this approach was developed for Ganoderma lucidum. Special attention was necessary for the appropriate selection of markers, for determining the reproducibility of the relative retention times (RRT), and for the accuracy of conversion factors (F). Finally, ten components were determined, with ganoderic acid A serving as single standard. Stable system parameters were established, and with successful resolution of those issues, this analytical method could be used more broadly.

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Posted on 16 September 2014 | 12:54 pm


Characterisation of triterpenes and new phenolic lipids in Cameroonian propolis

Publication date: October 2014
Source:Phytochemistry, Volume 106

Author(s): M.N. Kardar , T. Zhang , G.D. Coxon , D.G. Watson , J. Fearnley , V. Seidel

Chemical investigation of a sample of propolis originating from North-Western Cameroon led to the isolation of thirteen alk(en)ylphenols (113) (inseparable mixture) along with ?-amyrin (14), ?-amyrin (15), lupeol (16), cycloartenol (17), mangiferonic acid (18), ambonic acid (19), mangiferolic acid (20), ambolic acid (21), isomangiferolic acid (22) and nine alk(en)ylresorcinols (2331) (inseparable mixture). All compounds were identified following analysis of their spectroscopic data and comparison with previously published reports. Compounds (8), (12), (13) and (30) are new natural products. GC–MS analysis carried out on the alk(en)ylphenol and alk(en)ylresorcinol mixtures (dimethyl disulphide trimethylsilyl derivatives) revealed the presence of saturated and mono-unsaturated compounds with side chain lengths ranging from C11 to C19 and C15 to C19, respectively. The position of the double bond in mono-unsaturated derivatives was established from the characteristic fragments resulting from the cleavage of the bond between the two methylthio-substituted carbons. The most abundant compound in each mixture was 3-(12?Z-heptadecenyl)-phenol (10) and 5-(12?Z-heptadecenyl)-resorcinol (29). This study is the first to report the presence of triterpenes (except for lupeol) and phenolic lipids, including eighteen compounds previously unreported in bee glue, in an African sample.

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Investigation of a substrate-specifying residue within Papaver somniferum and Catharanthus roseus aromatic amino acid decarboxylases

Publication date: October 2014
Source:Phytochemistry, Volume 106

Author(s): Michael P. Torrens-Spence , Michael Lazear , Renee von Guggenberg , Haizhen Ding , Jianyong Li

Plant aromatic amino acid decarboxylases (AAADs) catalyze the decarboxylation of aromatic amino acids with either benzene or indole rings. Because the substrate selectivity of AAADs is intimately related to their physiological functions, primary sequence data and their differentiation could provide significant physiological insights. However, due to general high sequence identity, plant AAAD substrate specificities have been difficult to identify through primary sequence comparison. In this study, bioinformatic approaches were utilized to identify several active site residues within plant AAAD enzymes that may impact substrate specificity. Next a Papaver somniferum tyrosine decarboxylase (TyDC) was selected as a model to verify our putative substrate-dictating residues through mutation. Results indicated that mutagenesis of serine 372 to glycine enables the P. somniferum TyDC to use 5-hydroxytryptophan as a substrate, and reduces the enzyme activity toward 3,4-dihydroxy-L-phenylalanine (dopa). Additionally, the reverse mutation in a Catharanthus roseus tryptophan decarboxylase (TDC) enables the mutant enzyme to utilize tyrosine and dopa as substrates with a reduced affinity toward tryptophan. Molecular modeling and molecular docking of the P. somniferum TyDC and the C. roseus TDC enzymes provided a structural basis to explain alterations in substrate specificity. Identification of an active site residue that impacts substrate selectivity produces a primary sequence identifier that may help differentiate the indolic and phenolic substrate specificities of individual plant AAADs.

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Cytotoxic diterpenoids from Salvia yunnanensis

Publication date: October 2014
Source:Phytochemistry, Volume 106

Author(s): Chun-Yan Wu , Yang Liao , Zi-Gang Yang , Xing-Wei Yang , Xiao-Ling Shen , Rong-Tao Li , Gang Xu

Forty-six abietane type diterpenoids possessing nine different fused ring systems were characterized from the roots of Salvia yunnanensis, six of which (salyunnanins A–F, 16) had different nor-abietane, homo-abietane, seco-abietane, and normal abietane architectures. Their structures were elucidated by comprehensive NMR and MS spectroscopic analyses. The inhibitory activities of these isolates against six human tumor lines were tested in vitro. Several of the compounds exhibited substantial cytotoxicity with IC50 values of 0.86–10.1?M.

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Molecular and biochemical characterization of caffeine synthase and purine alkaloid concentration in guarana fruit

Publication date: September 2014
Source:Phytochemistry, Volume 105

Author(s): Flávia Camila Schimpl , Eduardo Kiyota , Juliana Lischka Sampaio Mayer , José Francisco de Carvalho Gonçalves , José Ferreira da Silva , Paulo Mazzafera

Guarana seeds have the highest caffeine concentration among plants accumulating purine alkaloids, but in contrast with coffee and tea, practically nothing is known about caffeine metabolism in this Amazonian plant. In this study, the levels of purine alkaloids in tissues of five guarana cultivars were determined. Theobromine was the main alkaloid that accumulated in leaves, stems, inflorescences and pericarps of fruit, while caffeine accumulated in the seeds and reached levels from 3.3% to 5.8%. In all tissues analysed, the alkaloid concentration, whether theobromine or caffeine, was higher in young/immature tissues, then decreasing with plant development/maturation. Caffeine synthase activity was highest in seeds of immature fruit. A nucleotide sequence (PcCS) was assembled with sequences retrieved from the EST database REALGENE using sequences of caffeine synthase from coffee and tea, whose expression was also highest in seeds from immature fruit. The PcCS has 1083bp and the protein sequence has greater similarity and identity with the caffeine synthase from cocoa (BTS1) and tea (TCS1). A recombinant PcCS allowed functional characterization of the enzyme as a bifunctional CS, able to catalyse the methylation of 7-methylxanthine to theobromine (3,7-dimethylxanthine), and theobromine to caffeine (1,3,7-trimethylxanthine), respectively. Among several substrates tested, PcCS showed higher affinity for theobromine, differing from all other caffeine synthases described so far, which have higher affinity for paraxanthine. When compared to previous knowledge on the protein structure of coffee caffeine synthase, the unique substrate affinity of PcCS is probably explained by the amino acid residues found in the active site of the predicted protein.

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Extracellular lipids of Camelina sativa: Characterization of chloroform-extractable waxes from aerial and subterranean surfaces

Publication date: October 2014
Source:Phytochemistry, Volume 106

Author(s): Fakhria M. Razeq , Dylan K. Kosma , Owen Rowland , Isabel Molina

Camelina sativa (L.) Crantz is an emerging low input, stress tolerant crop with seed oil composition suitable for biofuel and bioproduct production. The chemical compositions and ultrastructural features of surface waxes from C. sativa aerial cuticles, seeds, and roots were analyzed using gas chromatography and microscopy. Alkanes, primary fatty alcohols, and free fatty acids were common components of all analyzed organs. A particular feature of leaf waxes was the presence of alkyl esters of long-chain fatty acids and very long-chain fatty alcohols, ranging from C38 to C50 and dominated by C42, C44 and C46 homologues. Stem waxes were mainly composed of non-sterol pentacyclic triterpenes. Flowers accumulated significant amounts of methyl-branched iso-alkanes (C29 and C31 total carbon number) in addition to straight-chain alkanes. Seed waxes were mostly primary fatty alcohols of up to 32 carbons in length and unbranched C29 and C31 alkanes. The total amount of identified wax components extracted by rapid chloroform dipping of roots was 280?gg?1 (fresh weight), and included alkyl hydroxycinnamates, predominantly alkyl coumarates and alkyl caffeates. This study provides qualitative and quantitative information on the waxes of C. sativa root, shoot, and seed boundary tissues, allowing the relative activities of wax biosynthetic pathways in each respective plant organ to be assessed. This detailed description of the protective surface waxes of C. sativa may provide insights into its drought-tolerant and pathogen-resistant properties, and also identifies C. sativa as a potential source of renewable high-value natural products.

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Highlights

Analyses of chloroform-extractable waxes of Camelina sativa’s aerial and subterranean surfaces show both overlapping and distinctive chemical compositions within the same species.





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Effects of N source concentration and NH4+/NO3? ratio on phenylethanoid glycoside pattern in tissue cultures of Plantago lanceolata L.: A metabolomics driven full-factorial experiment with LC–ESI–MS3

Publication date: October 2014
Source:Phytochemistry, Volume 106

Author(s): Sándor Gonda , Attila Kiss-Szikszai , Zsolt Sz?cs , Csaba Máthé , Gábor Vasas

Tissue cultures of a medicinal plant, Plantago lanceolata L. were screened for phenylethanoid glycosides (PGs) and other natural products (NPs) with LC–ESI–MS3. The effects of N source concentration and NH4 +/NO3 ? ratio were evaluated in a full-factorial (FF) experiment. N concentrations of 10, 20, 40 and 60mM, and NH4 +/NO3 ? ratios of 0, 0.11, 0.20 and 0.33 (ratio of NH4 + in total N source) were tested. Several peaks could be identified as PGs, of which, 16 could be putatively identified from the MS/MS/MS spectra. N source concentration and NH4 +/NO3 ? ratio had significant effects on the metabolome, their effects on individual PGs were different despite these metabolites were of the same biosynthethic class. Chief PGs were plantamajoside and acteoside (verbascoside), their highest concentrations were 3.54±0.83% and 1.30±0.40% of dry weight, on media 10(0.33) and 40(0.33), respectively. NH4 +/NO3 ? ratio and N source concentration effects were examined on a set of 89 NPs. For most NPs, high increases in abundance were observed compared to Murashige–Skoog medium. Abundances of 42 and 10 NPs were significantly influenced by the N source concentration and the NH4 +/NO3 ? ratio, respectively. Optimal media for production of different NP clusters were 10(0), 10(0.11) and 40(0.33). Interaction was observed between NH4 +/NO3 ? ratio and N source concentration for many NPs. It was shown in simulated experiments, that one-factor at a time (OFAT) experimental designs lead to sub-optimal media compositions for production of many NPs, and alternative experimental designs (e.g. FF) should be preferred when optimizing medium N source for optimal yield of NPs. If using OFAT, the N source concentration is to be optimized first, followed by NH4 +/NO3 ? ratio, as this reduces the likeliness of suboptimal yield results.

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Highlights

Tissue cultures of Plantago lanceolata L. were grown on media with different N source compositions. Phenylethanoid glycosides were quantified by LC–MS, non-linear responses for yields were observed. The full-factorial experimental design and the applied metabolomic approach was shown to be superior to simpler designs with respect to optimization of yields.





Posted on 16 September 2014 | 12:54 pm


Corrigendum to “Prenylflavonoids isolated from Artocarpus champeden with TRAIL-resistance overcoming activity” [Phytochemistry 96 (2013) 299–304]

Publication date: October 2014
Source:Phytochemistry, Volume 106

Author(s): Tomohiro Minakawa , Kazufumi Toume , Midori A. Arai , Takashi Koyano , Thaworn Kowithayakorn , Masami Ishibashi







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Editorial Board/Publication Information

Publication date: October 2014
Source:Phytochemistry, Volume 106









Posted on 16 September 2014 | 12:54 pm


Labdane diterpenoids from Salvia reuterana

Publication date: Available online 15 September 2014
Source:Phytochemistry

Author(s): Mahdi Moridi Farimani , Mansour Miran

Three labdane diterpenoids, 14?-hydroxy-15-chlorosclareol (1), 14?-hydroxy-15-acetoxysclareol (2), and 6?-hydroxy-14?-epoxysclareol (3), together with the known diterpenoids sclareol (4), 6?-hydroxysclareol (5), and 14?-epoxysclareol (6), as well as other common plant constituents were isolated from the n-hexane extract of aerial parts of Salvia reuterana. The structures of the new compounds were established by extensive 1D and 2D NMR spectroscopic techniques. Compound 1 is the first example of a halogenated terpenoid in the genus Salvia. Compounds 1–6 were also tested for their inhibitory activity toward HeLa and MCF-7 cell lines. Preliminary structure–activity relationship studies indicated that double bond moiety in sclareol is an essential feature for activity and modification of this moiety significantly decreased the cytotoxic activity of the resulting compounds.

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The interaction of boron with glycolipids is required to increase tolerance to stresses in Anabaena PCC 7120

Publication date: October 2014
Source:Phytochemistry, Volume 106

Author(s): Isidro Abreu , Isabel Orús , Luis Bolaños , Ildefonso Bonilla

Boron (B) is an essential nutrient for heterocystous cyanobacteria growing under diazotrophic conditions. Under B-deficient conditions, the heterocyst envelope is highly disorganized, and the glycolipid layer is predominantly lost. Therefore, we examined whether B is implicated in the regulation of synthesis or processing and/or stability of glycolipids in Anabaena PCC 7120. RT-PCR analysis indicated that the expression of hglE was not significantly changed under B deficiency, suggesting that the synthesis of glycolipids during heterocyst formation was not compromised. In contrast, the overexpression of devB and hepA, encoding a glycolipid and a carbohydrate transporter, respectively, results in the instability of the envelope under B-deficient conditions. The capacity of borate to bind and stabilize molecules is considered the basis of any B biological function. Using a borate-binding-specific resin and thin layer chromatography, we detected the glycolipids that interact with B. Several heterocyst-specific glycolipids were detected as putative B ligands, suggesting a role for B in stabilizing the heterocyst envelope. Moreover, the glycolipids of Anabaena growing in non-diazotrophic conditions were also detected as putative B ligands. Although B is not essential for Anabaena under non-N2-fixing conditions, the presence of this micronutrient increased the tolerance of Anabaena to detergent treatment, salinity and hyperosmotic conditions. Taken together, the results of the present experiment suggest a beneficial role for B in environmental adaptation. Furthermore, we discuss the nutrient requirement for living organisms growing in nature and not under laboratory conditions.

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Posted on 16 September 2014 | 12:54 pm


Role of the plant cell wall in gravity resistance

Publication date: Available online 15 September 2014
Source:Phytochemistry

Author(s): Takayuki Hoson , Kazuyuki Wakabayashi

Gravity resistance, mechanical resistance to the gravitational force, is a principal graviresponse in plants, comparable to gravitropism. The cell wall is responsible for the final step of gravity resistance. The gravity signal increases the rigidity of the cell wall via the accumulation of its constituents, polymerization of certain matrix polysaccharides due to the suppression of breakdown, stimulation of cross-link formation, and modifications to the wall environment, in a wide range of situations from microgravity in space to hypergravity. Plants thus develop a tough body to resist the gravitational force via an increase in cell wall rigidity and the modification of growth anisotropy. The development of gravity resistance mechanisms has played an important role in the acquisition of responses to various mechanical stresses and the evolution of land plants.

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Posted on 16 September 2014 | 12:54 pm


Pectins, ROS homeostasis and UV-B responses in plant roots

Publication date: Available online 11 September 2014
Source:Phytochemistry

Author(s): Ken Yokawa , František Baluška

Light from the sun contains far-red, visible and ultra violet (UV) wavelength regions. Almost all plant species have been evolved under the light environment. Interestingly, several photoreceptors, expressing both in shoots and roots, process the light information during the plant life cycle. Surprisingly, Arabidopsis root apices express besides the UVR8 UV-B receptor, also root-specific UV-B sensing proteins RUS1 and RUS2 linked to the polar cell–cell transport of auxin. In this mini-review, we focus on reactive oxygen species (ROS) signaling and possible roles of pectins internalized via endocytic vesicle recycling system in the root-specific UV-B perception and ROS homeostasis.

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Identification and characterization of chlorogenic acids, chlorogenic acid glycosides and flavonoids from Lonicera henryi L. (Caprifoliaceae) leaves by LC–MSn

Publication date: Available online 15 September 2014
Source:Phytochemistry

Author(s): Rakesh Jaiswal , Heiko Müller , Anja Müller , Mohamed Gamaleldin Elsadig Karar , Nikolai Kuhnert

The chlorogenic acids, chlorogenic acid glycosides and flavonoids of the leaves of Lonicera henryi L. (Caprifoliaceae) were investigated qualitatively by liquid chromatography tandem mass spectrometry. Thirty-one chlorogenic acids and their glycosides were detected and characterized to their regioisomeric level on the basis of their unique fragmentation pattern in the negative ion mode tandem MS spectra. All of them were extracted for the first time from this source and thirteen of them were not reported previously in nature. For the positive identification of chlorogenic acid glycosides by LC–MS n , multiple reaction monitoring and targeted MS n experiments were performed. We have developed an LC–MS n method for the systematic identification of chlorogenic acid glycosides and were also able to discriminate between chlorogenic acids and their isobaric glycosides. It was also possible to discriminate between 5-O-(3?-O-caffeoyl glucosyl)quinic acid and 5-O-(4?-O-caffeoyl glucosyl)quinic acid by LC–MS n . This method can be applied for the rapid and positive identification of chlorogenic acids and their glycosides in plant materials, food and beverages.

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Posted on 16 September 2014 | 12:54 pm


Phytotoxic flavonoids from roots of Stellera chamaejasme L. (Thymelaeaceae)

Publication date: October 2014
Source:Phytochemistry, Volume 106

Author(s): Zhiqiang Yan , Hongru Guo , Jiayue Yang , Quan Liu , Hui Jin , Rui Xu , Haiyan Cui , Bo Qin

Allelopathy, the negative effect on plants of chemicals released to the surroundings by a neighboring plant, is an important factor which contributes to the spread of some weeds in plant communities. In this field, Stellera chamaejasme L. (Thymelaeaceae) is one of the most toxic and ecologically-threatening weeds in some of the grasslands of north and west China. Bioassay-guided fractionation of root extracts of this plant led to the isolation of eight flavonoids 18, whose structures were elucidated by spectroscopic analysis. All compounds obtained, except 7-methoxylneochaejasmin A (4) and (+)-epiafzelechin (5), showed strong phytotoxic activity against Arabidopsis thaliana seedlings. Seedling growth was reduced by neochamaejasmin B (1), mesoneochamaejasmin A (2), chamaejasmenin C (3), genkwanol A (6), daphnodorin B (7) and dihydrodaphnodorin B (8) with IC50 values of 6.9, 12.1, 43.2, 74.8, 7.1 and 27.3?g/mL, respectively, and all of these compounds disrupted root development. Endogenous auxin levels at the root tips of the A. thaliana DR5::GUS transgenic line were largely reduced by compounds 1, 2 and 68, and were increased by compound 4. Moreover, the inhibition rate of A. thaliana auxin transport mutants pin2 and aux17 by compounds 18 were all lower than the wild type (Col-0). The influence of these compounds on endogenous auxin distribution is thus proposed as a critical factor for the phytotoxic effect. Compounds 1, 2, 4 and 8 were found in soils associated with S. chamaejasme, and these flavonoids also showed phytotoxicity to Clinelymus nutans L., an associated weed of S. chamaejasme. These results indicated that some phytotoxic compounds from roots of S. chamaejasme may be involved in the potential allelopathic behavior of this widespread weed.

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Flavonol glycosides in the petal of Rosa species as chemotaxonomic markers

Publication date: Available online 11 September 2014
Source:Phytochemistry

Author(s): Ochir Sarangowa , Tsutomu Kanazawa , Makoto Nishizawa , Takao Myoda , Changxi Bai , Takashi Yamagishi

Thirteen flavonol glycosides were isolated from the petals of Rosa species belonging to the section Gallicanae, and their structures were identified from their spectroscopic data. These flavonol glycosides, along with two flavonol glycosides isolated from Rosa rugosa, in the petals of 31 Rosa species belonging to sections Gallicanae, Cinnamomeae, Caninae, and Synstylae were quantitatively analyzed by UPLC. The results indicated that the species belonging to these sections could be classified into four types (Type A, B, C and D) based on the pattern of flavonol glycoside contents, whereas the R. rugosa flavonol glycosides were detected only in section Cinnamomeae. A principal components analysis (PCA) calculated from the 15 flavonol glycosides contained in these samples supported the presence of four types. The distribution of the species in Type D (a group of Cinnamomeae) was shown to reflect close interrelationships, but species in Type B (one group of Gallicanae) could be subdivided into two groups, one of which contained species in section Synstylae. Moreover, the flavonol glycosides were grouped by sugar moieties: a disaccharide composed of two hexoses (S1), a hexose (S2), including a hexose with galloyl group, a pentose (S3), and a disaccharide composed of a hexose and a pentose (S4). The ratios of the amounts of S1S4 to total flavonol glycoside content indicated that differences among the four sections were more distinctive than the amounts of the 15 flavonol glycosides. The 31 samples were divided into Type B, composed of one type of Gallicanae and Synstylae, Type A+C, composed of another type of Gallicanae and Caninae, and Type D, composed of Cinnamomeae. The R. rugosa flavonol glycosides were shown to be important chemotaxonomic markers for the classification of species in Cinnamomeae, and this method of using flavonol glycosides as chemotaxonomic markers could be useful for the identification of Rosa species belonging to sections Gallicanae, Cinnamomeae, Caninae, and Synstylae.

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Posted on 16 September 2014 | 12:54 pm


Isolation and identification of an allelopathic phenylethylamine in rice

Publication date: Available online 8 September 2014
Source:Phytochemistry

Author(s): Ho Le Thi , Chung-Ho Lin , Reid J. Smeda , Nathan D. Leigh , Wei G. Wycoff , Felix B. Fritschi

Allelopathy is the process whereby an organic chemical (allelochemical) released from one plant influences the growth and development of other plants. Allelochemicals produced by specific rice (Oryza sativa L.) cultivars have potential to manage barnyard grass (Echinochloa crus-galli L.), a major yield-limiting weed species in rice production systems in Asia and North America. In this study, isolation and identification of an allelopathic compound, N-trans-cinnamoyltyramine (NTCT), in a Vietnamese rice cultivar ‘OM 5930’ was accomplished through bioassay-guided purification using reversed-phase liquid chromatography coupled with spectroscopic techniques, including tandem mass spectrometry, high resolution mass spectrometry, as well as one-dimensional and two-dimensional 1H NMR and 13C NMR spectroscopy. The identified compound, NTCT is considered a ?-phenylethylamine. NTCT inhibited root and hypocotyl growth of cress (Lepidium sativum L.), barnyard grass and red sprangletop (Leptochloa chinensis L. Nees) at concentrations as low as 0.24?M. The ED50 (concentration required for 50% inhibition) of NTCT on barnyard grass root and hypocotyl elongation were 1.35 and 1.85?M, respectively. Results further demonstrated that mortality of barnyard grass and red sprangletop seedlings was >80% at a concentration of 2.4?M of NTCT. By 20days after transplanting, 0.425nmol of NTCT per OM 5930 rice seedling was released into the culture solution. With concentrations of 42?gg?1 fresh weight, production of NTCT in intact rice plants can be considered high. These findings suggest that developing plants of Vietnamese rice cultivar OM 5930 release NTCT and may be utilized to suppress barnyard grass in rice fields. The potency of NTCT may encourage development of this compound as a bio-herbicide.

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Posted on 16 September 2014 | 12:54 pm


Chemical taxonomy of tree peony species from China based on root cortex metabolic fingerprinting

Publication date: Available online 11 September 2014
Source:Phytochemistry

Author(s): Chunnian He , Bing Peng , Yang Dan , Yong Peng , Peigen Xiao

The section Moutan of the genus Paeonia consists of eight species that are confined to a small area in China. A wide range of metabolites, including monoterpenoid glucosides, flavonoids, tannins, stilbenes, triterpenoids, steroids, paeonols, and phenols, have been found in the species belonging to section Moutan. However, although previous studies have analyzed the metabolites found in these species, the metabolic similarities that can be used for the chemotaxonomic distinction of section Moutan species are not yet clear. In this study, HPLC–DAD-based metabolic fingerprinting was applied to the classification of eight species: Paeonia suffruticosa, Paeonia qiui, Paeonia ostii, Paeonia rockii, Paeonia jishanensis, Paeonia decomposita, Paeonia delavayi, and Paeonia ludlowii. In total, of the 47 peaks that exhibited an occurrence frequency of 75% in all 23 tree peony samples, 43 of these metabolites were identified according to their retention times and UV absorption spectra, together with combined HPLC–QTOF-MS. These data were compared with reference standard compounds. The 43 isolated compounds included 17 monoterpenoid glucosides, 11 galloyl glucoses, 5 flavonoids, 6 paeonols and 4 phenols. Principal component analysis (PCA), and hierarchical cluster analysis (HCA), showed a clear separation between the species based on metabolomics similarities and four groups were identified. The results exhibited good agreement with the classical classification based on the morphological characteristics and geographical distributions of the subsections Vaginatae F.C. Stern and Delavayanae F.C. Stern with the exception of P. decomposita, which was found to be a transition species between these two subsections. According to their metabolic fingerprinting characteristics, P. ostii and P. suffruticosa can be considered one species, and this result is consistent with the viewpoint of medicinal plant scientists but different from that of classical morphological processing. Significantly large variations were obtained in the metabolic profiles of P. delavayi, whereas no significant difference was found between P. delavayi and P. ludlowii. This indicates that these two species have a close genetic relationship. In conclusion, the combination of HPLC–DAD and multivariate analyses has great potential for guiding future chemotaxonomic studies to examine the potential pharmaceutical value of the effective constituents of tree peony species and appears to be able to clarify the confusion and skepticism associated with the reported morphology- and molecular phylogenetics-based taxonomy of tree peonies.

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Posted on 16 September 2014 | 12:54 pm


Chemical interactions between plants in Mediterranean vegetation: The influence of selected plant extracts on Aegilops geniculata metabolome

Publication date: October 2014
Source:Phytochemistry, Volume 106

Author(s): Monica Scognamiglio , Vittorio Fiumano , Brigida D’Abrosca , Assunta Esposito , Young Hae Choi , Robert Verpoorte , Antonio Fiorentino

Allelopathy is the chemical mediated communication among plants. While on one hand there is growing interest in the field, on the other hand it is still debated as doubts exist at different levels. A number of compounds have been reported for their ability to influence plant growth, but the existence of this phenomenon in the field has rarely been demonstrated. Furthermore, only few studies have reported the uptake and the effects at molecular level of the allelochemicals. Allelopathy has been reported on some plants of Mediterranean vegetation and could contribute to structuring this ecosystem. Sixteen plants of Mediterranean vegetation have been selected and studied by an NMR-based metabolomics approach. The extracts of these donor plants have been characterized in terms of chemical composition and the effects on a selected receiving plant, Aegilops geniculata, have been studied both at the morphological and at the metabolic level. Most of the plant extracts employed in this study were found to have an activity, which could be correlated with the presence of flavonoids and hydroxycinnamate derivatives. These plant extracts affected the receiving plant in different ways, with different rates of growth inhibition at morphological level. The results of metabolomic analysis of treated plants suggested the induction of oxidative stress in all the receiving plants treated with active donor plant extracts, although differences were observed among the responses. Finally, the uptake and transport into receiving plant leaves of different metabolites present in the extracts added to the culture medium were observed.

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Highlights

Metabolomics highlighted the allelopathic potential of selected Mediterranean plants, allowing the identification of putative active compounds, as well as the study of the observed responses and the fate of allelochemicals.





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Acyl-ACP thioesterases from Camelina sativa: Cloning, enzymatic characterization and implication in seed oil fatty acid composition

Publication date: Available online 8 September 2014
Source:Phytochemistry

Author(s): Manuel Fernando Rodríguez-Rodríguez , Joaquín J. Salas , Rafael Garcés , Enrique Martínez-Force

Acyl-acyl carrier protein (ACP) thioesterases are intraplastidial enzymes that terminate de novo fatty acid biosynthesis in the plastids of higher plants by hydrolyzing the thioester bond between ACP and the fatty acid synthesized. Free fatty acids are then esterified with coenzyme A prior to being incorporated into the glycerolipids synthesized through the eukaryotic pathway. Acyl-ACP thioesterases belong to the TE14 family of thioester-active enzymes and can be classified as FatAs and FatBs, which differ in their amino acid sequence and substrate specificity. Here, the FatA and FatB thioesterases from Camelina sativa seeds, a crop of interest in plant biotechnology, were cloned, sequenced and characterized. The mature proteins encoded by these genes were characterized biochemically after they were heterologously expressed in Escherichia coli and purified. C. sativa contained three different alleles of both the FatA and FatB genes. These genes were expressed most strongly in expanding tissues in which lipids are very actively synthesized, such as developing seed endosperm. The CsFatA enzyme displayed high catalytic efficiency on oleoyl-ACP and CsFatB acted efficiently on palmitoyl-ACP. The contribution of these two enzymes to the synthesis of C. sativa oil was discussed in the light of these results.

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Posted on 16 September 2014 | 12:54 pm


Jatrophidin I, a cyclic peptide from Brazilian Jatropha curcas L.: Isolation, characterization, conformational studies and biological activity

Publication date: Available online 5 September 2014
Source:Phytochemistry

Author(s): Wanessa F. Altei , Douglas G. Picchi , Barbara M. Abissi , Guilherme M. Giesel , Otavio Flausino Jr. , Michèle Reboud-Ravaux , Hugo Verli , Edson Crusca Jr. , Edilberto R. Silveira , Eduardo M. Cilli , Vanderlan S. Bolzani

A cyclic peptide, jatrophidin I, was isolated from the latex of Jatropha curcas L. Its structure was elucidated by extensive 2D NMR spectroscopic analysis, with additional conformational studies performed using Molecular Dynamics/Simulated Annealing (MD/SA). Jatrophidin I had moderate protease inhibition activity when compared with pepstatin A; however, the peptide was inactive in antimalarial, cytotoxic and antioxidant assays.

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Posted on 16 September 2014 | 12:54 pm


Furofuran lignans display schistosomicidal and trypanocidal activities

Publication date: Available online 5 September 2014
Source:Phytochemistry

Author(s): Márcio Luis Andrade e Silva , Viviane Rodrigues Esperandim , Daniele da Silva Ferreira , Lizandra Guidi Magalhães , Thais Coelho Lima , Wilson Roberto Cunha , Dhammika N.P. Nanayakkara , Ana Carolina Pereira , Jairo Kenupp Bastos

Parasitic diseases continue to be a major worldwide health problem, and there is an urgent need for development of therapeutic drugs. This paper describes synthesis of dehydrodiferulic acid dilactone 1 and dehydrodisinapic acid dilactone 2 furofuran lignans by oxidative coupling of ferulic and sinapic acids, respectively. Their schistosomicidal, trypanocidal, and leishmanicidal activities were evaluated in vitro against Schistosoma mansoni adult worms, trypomastigote and amastigotes forms of Trypanosoma cruzi, and promastigote forms of Leishmania amazonensis. Compound 1 did not display significant schistosomicidal activity, but it presented potent trypanocidal activity, since it induced death of trypomastigotes and amastigotes with IC50/24h of 9.3?M and 7.3?M, respectively. Compound 2 had slight trypanocidal and schistosomicidal activities. None of the compounds were active against L. amazonensis. These results demonstrated that furofuran lignans are potentially useful for anti-parasitic drugs development and should be further investigated.

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Posted on 16 September 2014 | 12:54 pm


Age-dependent changes from allylphenol to prenylated benzoic acid production in Piper gaudichaudianum Kunth

Publication date: October 2014
Source:Phytochemistry, Volume 106

Author(s): Anderson M. Gaia , Lydia F. Yamaguchi , Christopher S. Jeffrey , Massuo J. Kato

HPLC-DAD and principal component analysis (PCA) of the 1H NMR spectrum of crude plant extracts showed high chemical variability among seedlings and adult organs of Piper gaudichaudianum. While gaudichaudianic acid was the major compound in the adult leaves, apiole and dillapiole were the major compounds in their seedling leaves. By the 15th month of seedling growth, the levels of apiole and dillapiole decreased and gaudichaudianic acid appeared along with two compounds, biosynthetically related to gaudichaudianic acid.

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Posted on 16 September 2014 | 12:54 pm


Very-long-chain 3-hydroxy fatty acids, 3-hydroxy fatty acid methyl esters and 2-alkanols from cuticular waxes of Aloe arborescens leaves

Publication date: Available online 4 September 2014
Source:Phytochemistry

Author(s): Radu C. Racovita , Chen Peng , Takayoshi Awakawa , Ikuro Abe , Reinhard Jetter

The present work aimed at a comprehensive chemical characterization of the cuticular wax mixtures covering leaves of the monocot species Aloe arborescens. The wax mixtures were found to contain typical aliphatic compound classes in characteristic chain length distributions, including alkanes (predominantly C31), primary alcohols (predominantly C28), aldehydes (predominantly C32), fatty acid methyl esters (predominantly C28) and fatty acids (bimodal distribution around C32 and C28). Alkyl esters ranging from C42 to C52 were identified, and found to mainly contain C28 alcohol linked to C16–C20 acids. Three other homologous series were identified as 3-hydroxy fatty acids (predominantly C28), their methyl esters (predominantly C28), and 2-alkanols (predominantly C31). Based on structural similarities and homolog distributions, the biosynthetic pathways leading to these novel wax constituents can be hypothesized. Further detailed analyses showed that the A. arborescens leaf was covered with 15?g/cm2 wax on its adaxial side and 36?g/cm2 on the abaxial side, with 3:2 and 1:1 ratios between epicuticular and intracuticular wax layers on each side, respectively. Terpenoids were found mainly in the intracuticular waxes, whereas very-long-chain alkanes and fatty acids accumulated to relatively high concentrations in the epicuticular wax, hence near the true surface of the leaf.

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Posted on 16 September 2014 | 12:54 pm


Frank A. Loewus (1919–2014): A life well spent and well remembered

Publication date: September 2014
Source:Phytochemistry, Volume 105

Author(s): Norman G. Lewis







Posted on 16 September 2014 | 12:54 pm


Graphical Contents List

Publication date: September 2014
Source:Phytochemistry, Volume 105









Posted on 16 September 2014 | 12:54 pm


Corosolic acid content and SSR markers in Lagerstroemia speciosa (L.) Pers.: A comparative analysis among populations across the Southern Western Ghats of India

Publication date: October 2014
Source:Phytochemistry, Volume 106

Author(s): K.S. Jayakumar , J.S. Sajan , R. Aswati Nair , P. Padmesh Pillai , S. Deepu , R. Padmaja , A. Agarwal , A.G. Pandurangan

Lagerstroemia speciosa commonly known as ‘Banaba’ is native of south–east Asia which exhibits both horticultural and therapeutic value. The anti-diabetic and anti-obese property of the tree is attributed to corosolic acid (CRA)-a pentacyclic triterpene seen predominantly in the mature leaves. Although there are studies on either chemical or genetic variation in L. speciosa from different regions, none have dealt with their association to discuss the formation of chemical diversity. For the first time, we have analyzed CRA content in 12 natural populations corresponding to 42 samples seen in the Southern Western Ghats (SWG) using chromatography techniques and genetic variation estimated using SSR markers. Significant variation in percentage distribution of CRA ranging from 0.005% to 0.868% dr.wt. was recorded wherein populations from the north SWG contain relatively more active principle (mean=0.321%) than their counterparts in the south (mean=0.064%). Similarly, SSR data showing relatively high rate of gene flow (Nm=2.72) and low genetic differentiation (F ST =0.14) is indicative that populations from north are genetically more diverse than those in the south (Nm=0.48; F ST =0.38). The scatter plot derived by Principle Component Analysis (PCA) of chemical and genetic data shows similar pattern of clustering that reveals strong association between the two sets of data. It is concluded that the observed variation in CRA content in natural populations of the species depends more on the genetic background and less on edaphic factors.

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Posted on 16 September 2014 | 12:54 pm


Expression of terpene synthase genes associated with the formation of volatiles in different organs of Vitis vinifera

Publication date: September 2014
Source:Phytochemistry, Volume 105

Author(s): Fabiola Matarese , Angela Cuzzola , Giancarlo Scalabrelli , Claudio D’Onofrio

Plants produce a plethora of volatile organic compounds (VOCs) which are important in determining the quality and nutraceutical properties of horticultural food products, including the taste and aroma of wine. Given that some of the most prevalent grape aroma constituents are terpenoids, we investigated the possible variations in the relative expression of terpene synthase (TPS) genes that depend on the organ. We thus analysed mature leaves, young leaves, stems, young stems, roots, rachis, tendrils, peduncles, bud flowers, flowers and berries of cv Moscato bianco in terms of their VOC content and the expression of 23 TPS genes. In terms of the volatile characterization of the organs by SPME/GC–MS analysis, flower buds and open flowers appeared to be clearly distinct from all the other organs analysed in terms of their high VOC concentration. Qualitatively detected VOCs clearly separated all the vegetative organs from flowers and berries, then the roots and rachis from other vegetative organs and flowers from berries, which confirms the specialization in volatile production among different organs. Our real-time RT-PCR results revealed that the majority of TPS genes analysed exhibited detectable transcripts in all the organs investigated, while only some were found to be expressed specifically in one or just a few organs. In most cases, we found that the known products of the in vitro assay of VvTPS enzymes corresponded well to the terpenes found in the organs in which the encoding gene was expressed, as in the case of (E)-?-caryophyllene synthases, ?-terpineol synthase and ?-farnesene synthase. In addition, we found groups of homologous TPS genes, such as (E)-?-caryophyllene and ?-ocimene synthases, expressed distinctively in the various tissues. This thus confirmed the subfunctionalization events and a specialization on the basis of the organs in which they are mostly expressed.

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Posted on 16 September 2014 | 12:54 pm


Cytogeography of essential oil chemotypes of Eremophila longifolia F. Muell (Scrophulariaceae)

Publication date: September 2014
Source:Phytochemistry, Volume 105

Author(s): Nicholas John Sadgrove , Graham Lloyd Jones

Previous studies have demonstrated that the widely distributed desert plant Eremophila longifolia has at least six geographically defined essential oil chemotypes. The focus of the present study is to extend and enhance information concerning known chemotypes and to investigate the involvement of cell nuclei ploidy in this variation. Forty field collected specimens of E. longifolia were taken from most of the mainland states of Australia then subjected to hydrodistillation to produce essential oils, which were then chemically characterised. Ploidy was determined using relative fluorescence of cell nuclei stained with propidium iodide, measured in a flow cytometer. Using principal component analysis (PCA), at least three essential oil chemotypes, in addition to the six already described, were identified in the present study. Previously described high yielding essential oil chemotypes were also characterised in terms of diploidy. For the first time diploid populations were identified in New South Wales, correlating with high yielding isomenthone/menthone and karahanaenone chemotypes. Furthermore, the separate diploid population previously described from Western Australia was demonstrated to be the safrole/methyl eugenol type, which is restricted to a small geographic range in far north-west Western Australia (Murchison District). All other chemotypes were shown to be tetraploid, including apparently randomly emerging individuals, representative of chemotypes producing low yields of isomenthone/menthone and karahanaenone similar in composition to the high yielding diploid types.

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Posted on 16 September 2014 | 12:54 pm


Membrane-forming lipids of wild halophytes growing under the conditions of Prieltonie of South Russia

Publication date: September 2014
Source:Phytochemistry, Volume 105

Author(s): Olga A. Rozentsvet , Victor N. Nesterov , Elena S. Bogdanova

The composition of membrane-forming lipids has been examined for 10 wild halophyte species growing in southern Russian on alkaline soil. The plants belong to seven taxa of family rank: by their life form, which are semi-shrubs, herbaceous annuals, and perennial plants; their salt tolerance, which are classified as the euhalophytes, crynohalophytes, and glycohalophytes; and by their sensitivity to water, classifications of mesoxerophytes and xeromesophytes. Parallels have been found between the lipid composition and the ecological status of the plants. It has also been revealed that the similarity in the glyco- and phospholipid composition of different plant groups relates to the water factor and the type of salt accumulation, respectively. The fatty acid compositions of the examined plants is determined at the species level.

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Posted on 16 September 2014 | 12:54 pm


What the devil is in your phytomedicine? Exploring species substitution in Harpagophytum through chemometric modeling of 1H-NMR and UHPLC-MS datasets

Publication date: October 2014
Source:Phytochemistry, Volume 106

Author(s): Nontobeko P. Mncwangi , Alvaro M. Viljoen , Jianping Zhao , Ilze Vermaak , Wei Chen , Ikhlas Khan

Harpagophytum procumbens (Pedaliaceae) and its close taxonomical ally Harpagophytum zeyheri, indigenous to southern Africa, are being harvested for exportation to Europe where phytomedicines are developed to treat inflammation-related disorders. The phytochemical variation within and between natural populations of H. procumbens (n =241) and H. zeyheri (n =107) was explored using proton nuclear magnetic resonance (1H-NMR) and ultra-high performance liquid chromatography coupled to mass spectrometry (UHPLC-MS) in combination with multivariate data analysis methods. The UHPLC-MS results revealed significant variation in the harpagoside content: H. procumbens (0.17–4.37%); H. zeyheri (0.00–3.07%). Only 41% of the H. procumbens samples and 17% of the H. zeyheri samples met the pharmacopoeial specification of ?1.2%. Both principal component analysis (PCA) and orthogonal projections to latent structures discriminant analysis (OPLS-DA) indicated separation based on species (UHPLC-MS data OPLS-DA model statistics: R 2X=0.258, R 2Y (cum)=0.957 and Q 2(cum)=0.934; 1H-NMR data OPLS-DA model statistics: R 2X=0.830, R 2Y=0.865 (cum) and Q 2(cum)=0.829). It was concluded that two species are not chemically equivalent and should not be used interchangeably.

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Posted on 16 September 2014 | 12:54 pm


Indolosesquiterpene alkaloids from the Cameroonian medicinal plant Polyalthia oliveri (Annonaceae)

Publication date: September 2014
Source:Phytochemistry, Volume 105

Author(s): Simeon Fogue Kouam , Alain Wembe Ngouonpe , Marc Lamshöft , Ferdinand Mouafo Talontsi , Jonathan O. Bauer , Carsten Strohmann , Bonaventure Tchaleu Ngadjui , Hartmut Laatsch , Michael Spiteller

The stem bark of Polyalthia oliveri was screened for its chemical constituents using liquid chromatography high resolution mass spectrometry resulting in the isolation of three indolosesquiterpene alkaloids named 8?-polyveolinone (1), N-acetyl-8?-polyveolinone (2) and N-acetyl-polyveoline (3), together with three known compounds, dehydro-O-methylisopiline (4), N-methylurabaine (5) and polycarpol (6). The structures of the compounds were elucidated by means of high resolution mass spectrometry and different NMR techniques and chemical transformations. Their absolute configurations were assigned by ab-initio calculation of CD and ORD data (for 2 and 3) and X-ray diffraction analysis (for 2). Compounds 2 and 3 exhibited moderate antiplasmodial activity against erythrocytic stages of chloroquine-sensitive Plasmodium falciparum NF54 strain and low cytotoxicity on rat skeletal myoblast (L6) cell line.

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Posted on 16 September 2014 | 12:54 pm


Asphodosides A-E, anti-MRSA metabolites from Asphodelus microcarpus

Publication date: September 2014
Source:Phytochemistry, Volume 105

Author(s): Mohammed M. Ghoneim , Khaled M. Elokely , Atef A. El-Hela , Abd-Elsalam I. Mohammad , Melissa Jacob , Mohamed M. Radwan , Robert J. Doerksen , Stephen J. Cutler , Samir A. Ross

Bioassay guided fractionation of the ethanolic extract of Asphodelus microcarpus Salzm. et Viv. (Xanthorrhoeaceae or Asphodelaceae) resulted in isolation of five compounds identified as asphodosides A-E (15). Compounds 24 showed activity against methicillin resistant Staphylococcus aureus (MRSA) with IC50 values of 1.62, 7.0 and 9.0?g/mL, respectively. They also exhibited activity against Staphylococcus aureus (non-MRSA) with IC50 values of 1.0, 3.4 and 2.2?g/mL, respectively. The structure elucidation of isolated metabolites was carried out using spectroscopic data (1D and 2D NMR), optical rotation and both experimental and calculated electronic circular dichroism (ECD).

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Posted on 16 September 2014 | 12:54 pm


Comprehensive approach for the detection of antifungal compounds using a susceptible strain of Candida albicans and confirmation of in vivo activity with the Galleria mellonella model

Publication date: September 2014
Source:Phytochemistry, Volume 105

Author(s): Quentin Favre-Godal , Stéphane Dorsaz , Emerson Ferreira Queiroz , Céline Conan , Laurence Marcourt , Bambang Prajogo Eko Wardojo , Francine Voinesco , Aurélie Buchwalder , Katia Gindro , Dominique Sanglard , Jean-Luc Wolfender

An efficient screening strategy for the identification of potentially interesting low-abundance antifungal natural products in crude extracts that combines both a sensitive bioautography assay and high performance liquid chromatography (HPLC) microfractionation was developed. This method relies on high performance thin layer chromatography (HPTLC) bioautography with a hypersusceptible engineered strain of Candida albicans (DSY2621) for bioactivity detection, followed by the evaluation of wild type strains in standard microdilution antifungal assays. Active extracts were microfractionated by HPLC in 96-well plates, and the fractions were subsequently submitted to the bioassay. This procedure enabled precise localisation of the antifungal compounds directly in the HPLC chromatograms of the crude extracts. HPLC-PDA-mass spectrometry (MS) data obtained in parallel to the HPLC antifungal profiles provided a first chemical screening about the bioactive constituents. Transposition of the HPLC analytical conditions to medium-pressure liquid chromatography (MPLC) allowed the efficient isolation of the active constituents in mg amounts for structure confirmation and more extensive characterisation of their biological activities. The antifungal properties of the isolated natural products were evaluated by their minimum inhibitory concentration (MIC) in a dilution assay against both wild type and engineered strains of C. albicans. The biological activity of the most promising agents was further evaluated in vitro by electron microscopy and in vivo in a Galleria mellonella model of C. albicans infection. The overall procedure represents a rational and comprehensive means of evaluating antifungal activity from various perspectives for the selection of initial hits that can be explored in more in-depth mode-of-action studies. This strategy is illustrated by the identification and bioactivity evaluation of a series of antifungal compounds from the methanolic extract of a Rubiaceae plant, Morinda tomentosa, which was used as a model in these studies.

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Posted on 16 September 2014 | 12:54 pm


Chemical constituents of Abies nukiangensis

Publication date: October 2014
Source:Phytochemistry, Volume 106

Author(s): Yong-Li Li , Yan-Xia Gao , Hui-Zi Jin , Lei Shan , Xue-Song Liang , Xi-Ke Xu , Xian-Wen Yang , Ning Wang , Andre Steinmetz , Zhilei Chen , Wei-Dong Zhang

During a survey on chemical constituents of Abies nukiangensis, seven previously unreported compounds, including six triterpenes (16) and one phenol (7) were isolated and characterized, together with 37 known miscellaneous chemical constituents. The structures of compounds 17 were established mainly by extensive analysis of the 1D and 2D NMR, as well as HRMS data. The absolute configurations of compounds 1 and 8 were confirmed unambiguously by the Cu-K? X-ray crystallography. Compounds 3 and 810 showed significant anti-hepatitis C virus effects with EC50 values of 3.73, 2.67, 1.33 and 2.25?M, respectively.

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Posted on 16 September 2014 | 12:54 pm


Phytotoxic cis-clerodane diterpenoids from the Chinese liverwort Scapania stephanii

Publication date: September 2014
Source:Phytochemistry, Volume 105

Author(s): Rui-Juan Li , Yi Sun , Bin Sun , Xiao-Ning Wang , Shan-Shan Liu , Jin-Chuan Zhou , Jian-Ping Ye , Yu Zhao , Lei Liu , Kuo-Hsiung Lee , Hong-Xiang Lou

Five cis-clerodane diterpenoids, stephanialides A?E, along with seven known cis-clerodanes, scaparvins A?C, parvitexins B and C, 3-chloro-4-hydroxy-parvitexin A, and scapanialide B, were isolated from the Chinese liverwort Scapania stephanii. Their structures were established unequivocally on the basis of spectroscopic data. The absolute configuration of stephanialide A was determined by analysis of CD data using the octant rule. Phytotoxic activity evaluation showed that this type of diterpenoids can significantly inhibit root elongation of the seeds of Arabidopsis thaliana, Lepidium sativum and Brassica pekinensis.

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Posted on 16 September 2014 | 12:54 pm





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