Publication date: Available online 7 November 2014 Source:Phytochemistry Author(s): Chrysoula Gousiadou , Tetsuo Kokubun , Charlotte H. Gotfredsen , Søren R. Jensen From Manulea altissima (Scrophulariaceae) were isolated five known secoiridoid glucosides sweroside, eustomoside, eustoside, secoxyloganin and secologanoside as well as the 4?-O-rhamnopyranosyl-feruloyl ester of adoxosidic acid, named altissimoside. Also, the caffeoyl phenylethanoid glycoside verbascoside was isolated. In addition two previously unknown terpenoid esters of 6?-hydroxy 8-epi-boschnaloside, named manucoside A and B were isolated from a formerly obtained fraction from the work-up of Manulea corymbosa. The distribution of iridoid glucosides in the Scrophulariaceae is discussed.
Publication date: November 2014 Source:Phytochemistry, Volume 107 Author(s): Minjie Qian , Yongwang Sun , Andrew C. Allan , Yuanwen Teng , Dong Zhang ‘Zaosu’ pear, a hybrid of Pyrus pyrifolia and Pyrus communis, is a popular cultivar developed in China. ‘Zaosu Red’ is a bud sport of ‘Zaosu’ with red shoots, young leaves, and fruit. After grafting of ‘Zaosu Red’, reverse mutations in some branches lead to a loss of colour in leaves and stems. Also, the mature fruit of ‘Zaosu Red’ exhibits two phenotypes; fully red and striped. The aim of this study was to establish the mechanism of the red colour mutation in ‘Zaosu’ and the striped pigmentation pattern in fruit of ‘Zaosu Red’. The accumulation of anthocyanins and transcript levels of the genes PpUFGT2 and PyMYB10 were highly correlated. The open reading frames (ORF) and promoter regions of these two key genes were cloned and compared between ‘Zaosu’ and its bud sports, but no sequence differences were found. The R2R3 MYB, PyMYB10, can activate expression of genes encoding enzymes of the anthocyanin biosynthetic pathway. A yeast one-hybrid assay showed that PyMYB10 was associated with the ?658 to ?172bp fragment of the PpUFGT2 promoter, probably via a MYB binding site (MBS) located at ?466bp. The PyMYB10 promoter had lower methylation levels in anthocyanin-rich tissues, indicating that the red bud sport of ‘Zaosu’ pear and the striped pigmentation pattern of ‘Zaosu Red’ pear are associated with demethylation of the PyMYB10 promoter.
Publication date: Available online 29 October 2014 Source:Phytochemistry Author(s): Nadine Strehmel , Christoph Böttcher , Stephan Schmidt , Dierk Scheel To explore the chemical composition of root exudates of the model plant Arabidopsis thaliana a workflow for nontargeted metabolite profiling of the semipolar fraction of root exudates was developed. It comprises hydroponic plant cultivation and sampling of root exudates under sterile conditions, sample preparation by solid-phase extraction and analysis by reversed-phase UPLC/ESI-QTOFMS. Following the established workflow, root exudates of six-week-old plants were profiled and a set of reproducibly occurring molecular features was compiled. To structurally elucidate the corresponding metabolites, accurate mass tandem mass spectrometry and on-line hydrogen/deuterium exchange were applied. Currently, a total of 103 compounds were detected and annotated by elemental composition of which more than 90 were structurally characterized or classified. Among them, 42 compounds were rigorously identified using an authenticated standard. The compounds identified so far include nucleosides, deoxynucleosides, aromatic amino acids, anabolites and catabolites of glucosinolates, dipeptides, indolics, salicylic and jasmonic acid catabolites, coumarins, mono-, di- and trilignols, hydroxycinnamic acid derivatives and oxylipins and exemplify the high chemical diversity of plant root exudates.
Publication date: Available online 4 November 2014 Source:Phytochemistry Author(s): Wen Dong , Marcia Kieliszewski , Michael A. Held The regulation of plant cell growth and early defense response involves the insolubilization of hydroxyproline-rich glycoproteins (HRGPs), such as extensin, in the primary cell wall. In tomato (Lycopersicon esculentum), insolubilization occurs by the formation of tyrosyl-crosslinks catalyzed specifically by the pI 4.6 extensin peroxidase (EP). To date, neither the gene encoding EP nor the protein itself has been identified. Here, we have identified tomato EP candidates using both proteomic and bioinformatic approaches. Bioinformatic screening of the tomato genome yielded eight EP candidates, which contained a putative signal sequence and a predicted pI near 4.6. Biochemical fractionation of tomato culture media followed by proteomic detection further refined our list of EP candidates to three, with the lead candidate designated (CG5). To test for EP crosslinking activity, we cloned into a bacterial expression vector the CG5 open-reading frame from tomato cDNA. The CG5 was expressed in Escherichia coli, fractionated from inclusion bodies, and folded in vitro. The peroxidase activity of CG5 was assayed and quantified by ABTS (2,2?-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)) assay. Subsequent extensin crosslinking assays showed that CG5 can covalently crosslink authentic tomato P1 extensin and P3-type extensin analogs in vitro supporting our hypothesis that CG5 encodes a tomato EP.
Publication date: Available online 18 November 2014 Source:Phytochemistry Author(s): Johannes Niebler , Andrea Buettner Frankincense has been known, traded and used throughout the ages for its exceptional aroma properties, and is still commonly used in both secular and religious settings to convey a pleasant odor. Surprisingly, the odoriferous principle(s) underlying its unique odor profile have never been published. In this study, resin samples of Boswellia sacra Flueck. from both Somalia and Oman were investigated by aroma extract dilution analysis. In a comprehensive, odor-activity guided approach both chemo-analytical and human-sensory parameters were used to identify odor active constituents of the volatile fraction of B. sacra. Among the key odorants found were ?-pinene, ?-myrcene, linalool, p-cresol and two unidentified sesquiterpenoids. Overall, a total of 23 odorants were detected and analyzed by gas chromatography–olfactometry and heart-cut two-dimensional gas chromatography–mass spectrometry/olfactometry. The majority of the identified odorant compounds were oxygenated monoterpenes, along with some relevant mono- and sesquiterpenes and only one diterpenoid substance. Several of these compounds were reported here for the first time as odorous constituents in B. sacra. Identifying bioactive compounds might support a better understanding with regard to the potential benefits of frankincense, for example in aromatherapy or ecclesial settings.
Publication date: Available online 8 November 2014 Source:Phytochemistry Author(s): Huaping Zhang , Cong-Mei Cao , Robert J. Gallagher , Victor W. Day , Kelly Kindscher , Barbara N. Timmermann Six withanolides (1–6), as well as two known withanolides (physachenolide D 7 and withanoside VI 8), were isolated from the aerial parts of Physalis coztomatl (Solanaceae). Structural elucidations of 1–6 were achieved through 2D NMR and other spectroscopic techniques, while the structure of 1 was confirmed by X-ray crystallographic analysis. In addition, the stereochemical orientation of the 17-hydroxy group in withanolides was discussed in relation to 13C NMR shifts of C-12, 13, 14 and 16. Such analysis established that coagulansin A contains a 17?-hydroxy moiety rather than the reported 17?-hydroxy functionality, and has been revised accordingly.
Publication date: November 2014 Source:Phytochemistry, Volume 107 Author(s): Hang Liu , Fei Li , Chuang-Jun Li , Jing-Zhi Yang , Li Li , Nai-Hong Chen , Dong-Ming Zhang Clausena lansium Skeels, a member of the Rutaceae, is a shrub or small tree with grapelike fruits. Several parts of this plant have been used in folk medicine. A bioactive constituent investigation of the stems of C. lansium herein resulted in isolation of four furanocoumarins, claucoumarins A–D, and 13 known analogs. Their structures were elucidated on the basis of spectroscopic analyses, including UV, IR, MS, and NMR experiments, and their absolute configurations were determined by CD experiments. Using an in vitro system, several of these compounds showed selective neuroprotective effects at a concentration of 10?M.
Publication date: Available online 6 November 2014 Source:Phytochemistry Author(s): Ulrike Grienke , Teresa Kaserer , Florian Pfluger , Christina E. Mair , Thierry Langer , Daniela Schuster , Judith M. Rollinger The species complex around the medicinal fungus Ganoderma lucidum Karst. (Ganodermataceae) is widely known in traditional medicines, as well as in modern applications such as functional food or nutraceuticals. A considerable number of publications reflects its abundance and variety in biological actions either provoked by primary metabolites, such as polysaccharides, or secondary metabolites, such as lanostane-type triterpenes. However, due to this remarkable amount of information, a rationalization of the individual Ganoderma constituents to biological actions on a molecular level is quite challenging. To overcome this issue, a database was generated containing meta-information, i.e., chemical structures and biological actions of hitherto identified Ganoderma constituents (279). This was followed by a computational approach subjecting this 3D multi-conformational molecular dataset to in silico parallel screening against an in-house collection of validated structure- and ligand-based 3D pharmacophore models. The predictive power of the evaluated in silico tools and hints from traditional application fields served as criteria for the model selection. Thus, the focus was laid on representative druggable targets in the field of viral infections (5) and diseases related to the metabolic syndrome (22). The results obtained from this in silico approach were compared to bioactivity data available from the literature. 89 and 197 Ganoderma compounds were predicted as ligands of at least one of the selected pharmacological targets in the antiviral and the metabolic syndrome screening, respectively. Among them only a minority of individual compounds (around 10%) has ever been investigated on these targets or for the associated biological activity. Accordingly, this study discloses putative ligand target interactions for a plethora of Ganoderma constituents in the empirically manifested field of viral diseases and metabolic syndrome which serve as a basis for future applications to access yet undiscovered biological actions of Ganoderma secondary metabolites on a molecular level.
Publication date: Available online 18 November 2014 Source:Phytochemistry Author(s): Abdulmagid Alabdul Magid , Hamid Morjani , Dominique Harakat , Claudie Madoulet , Vincent Dumontet , Catherine Lavaud Seven triterpenoid glycosides, named meliosmosides A–G, were isolated from the leaves of Meliosma henryi Diels (Sabiaceae). Their structures were elucidated by different spectroscopic methods including 1D and 2D NMR experiments as well as HRESIMS analysis. Isolated compounds were evaluated for their cytotoxic activity against KB cell line.
Publication date: November 2014 Source:Phytochemistry, Volume 107 Author(s): Hirotomo Kihara , Maya Tanaka , Katsuyuki T. Yamato , Akira Horibata , Atsushi Yamada , Sayaka Kita , Kimitsune Ishizaki , Masataka Kajikawa , Hideya Fukuzawa , Takayuki Kohchi , Yoshihiko Akakabe , Kenji Matsui Eight-carbon (C8) volatiles, such as 1-octen-3-ol, octan-3-one, and octan-3-ol, are ubiquitously found among fungi and bryophytes. In this study, it was found that the thalli of the common liverwort Marchantia polymorpha, a model plant species, emitted high amounts of C8 volatiles mainly consisting of (R)-1-octen-3-ol and octan-3-one upon mechanical wounding. The induction of emission took place within 40min. In intact thalli, 1-octen-3-yl acetate was the predominant C8 volatile while tissue disruption resulted in conversion of the acetate to 1-octen-3-ol. This conversion was carried out by an esterase showing stereospecificity to (R)-1-octen-3-yl acetate. From the transgenic line of M. polymorpha (des6KO) lacking arachidonic acid and eicosapentaenoic acid, formation of C8 volatiles was only minimally observed, which indicated that arachidonic and/or eicosapentaenoic acids were essential to form C8 volatiles in M. polymorpha. When des6KO thalli were exposed to the vapor of 1-octen-3-ol, they absorbed the alcohol and converted it into 1-octen-3-yl acetate and octan-3-one. Therefore, this implied that 1-octen-3-ol was the primary C8 product formed from arachidonic acid, and further metabolism involving acetylation and oxidoreduction occurred to diversify the C8 products. Octan-3-one was only minimally formed from completely disrupted thalli, while it was formed as the most abundant product in partially disrupted thalli. Therefore, it is assumed that the remaining intact tissues were involved in the conversion of 1-octen-3-ol to octan-3-one in the partially disrupted thalli. The conversion was partly promoted by addition of NAD(P)H into the completely disrupted tissues, suggesting an NAD(P)H-dependent oxidoreductase was involved in the conversion.
Publication date: November 2014 Source:Phytochemistry, Volume 107 Author(s): Silvia Galasso , Severina Pacifico , Nadine Kretschmer , San-Po Pan , Sabina Marciano , Simona Piccolella , Pietro Monaco , Rudolf Bauer Thymus longicaulis C. Presl. (Lamiaceae) is a small aromatic perennial herb typical of the Illyric-Mediterranean flora, traditionally used as remedy for cold, flu, cough, nephritis and abdominal pain. In order to carry out a thorough chemical and biological screening of the plant and to explore phenophases influence on its polyphenol content, samples of the plant were collected at different phases during its life cycle (July/October 2012 and January/April 2013). Each sample, previously extracted using a hydroalcoholic solution, was phytochemically analyzed for its metabolic constitution applying LC-DAD-ESI-MS/MS techniques. Although identified metabolites were differently concentrated at the various collection times, T. longicaulis leaf extracts were mainly constituted by low molecular weight phenols, and flavonoids. Rosmarinic acid was found as the main metabolite in Oct12 sample. Chemopreventive efficacy of the investigated extracts, by means of their anti-inflammatory, cytotoxic and antioxidant activities, was assessed. To this purpose, each extract underwent an extensive screening towards five human cell lines: CCRF-CEM (leukemia); U251 (glioblastoma); MDA-MB-231 (breast cancer); HCT-116 (colon cancer) and MRC-5 (lung fibroblasts) through XTT [2,3bis(2-metoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino)carbonyl]-2H tetrazolium hydroxide] test. The ability of the extracts to counteract cyclooxygenase-2 (COX-2) expression was also evaluated by COX-2 expression assay in human THP-1 monocyte-derived macrophages. COX-2 inhibition could represent a valuable anticancer strategy as it is associated with carcinogenesis and over-expressed in a variety of human malignancies. Oct12 extract, which was particularly rich in rosmarinic acid and methylapigenin, exhibited a strong antioxidant and anti-inflammatory effectiveness.
Thymus longicaulis C. Presl samples, collected at different phenological stages, were analyzed for their chemical composition and antioxidant and anti-inflammatory properties. The hydroalcoholic extract from plants collected in the month of October contained a large amount of rosmarinic acid and methylapigenin and showed the highest antioxidant and anti-inflammatory activities.
Publication date: Available online 16 November 2014 Source:Phytochemistry Author(s): Laura Carmona-Salazar , Mohammed El Hafidi , Nora Gutiérrez-Nájera , Liliana Noyola-Martínez , Ariadna González-Solís , Marina Gavilanes-Ruíz It is essential to establish the composition of the plant plasma membrane in order to understand its organization and behavior under continually changing environments. Knowledge of the lipid phase, in particular the fatty acid (FA) complex repertoire, is important since FAs determine many of the physical–chemical membrane properties. FAs are constituents of the membrane glycerolipid and sphingolipid backbones and can also be linked to some sterols. In addition, FAs are components of complex lipids that can constitute membrane micro-domains, and the use of detergent-resistant membranes is a common approach to study their composition. The diversity and cellular allocation of the membrane lipids containing FAs are very diverse and the approaches to analyze them provide only general information. In this work, a detailed FA analysis was performed using highly purified plasma membranes from bean leaves and germinating maize embryos and their respective detergent-resistant membrane preparations. The analyses showed the presence of a significant amount of very long chain FAs (containing 28C, 30C and 32C), in both plasma membrane preparations from bean and maize, that have not been previously reported. Herein is demonstrated that a significant enrichment of very long chain saturated FAs and saturated FAs can occur in detergent-resistant membrane preparations, as compared to the plasma membranes from both plant species. Considering that a thorough analysis of FAs is rarely performed in purified plasma membranes and detergent-resistant membranes, this work provides qualitative and quantitative evidence on the contributions of the length and saturation of FAs to the organization of the plant plasma membrane and detergent-resistant membranes.
Publication date: Available online 7 November 2014 Source:Phytochemistry Author(s): Meng Wang , Li-Xin Gao , Jue Wang , Jing-Ya Li , Mei-Hua Yu , Jia Li , Ai-Jun Hou Eight Diels–Alder adducts, morbilisins A–H (1–8), a known analogue, chalcomoracin (9), together with eleven known flavonoids and 2-arylbenzofurans, were isolated from the leaves of Morus notabilis. Their structures were elucidated by extensive spectroscopic analysis, including 1D, 2D NMR, MS, and ECD data. Compounds 1, 5, and 7–9 showed inhibition against PTP1B phosphatase activity in vitro.
Publication date: November 2014 Source:Phytochemistry, Volume 107 Author(s): Yong Jiang , Ke-Wu Zeng , Bruno David , Georges Massiot Nine non-phenolic compounds, including four furanylmethyl glycosides, angularides A–D, one ent-kaurane diterpene glycoside, angularin A, and four triterpenoid saponins, angulasaponins A–D, were isolated from seeds of Vigna angularis, together with eight known compounds. Their structures were elucidated on the basis of extensive 1D and 2D NMR spectroscopic analysis as well as chemical methods. Angularin A, angulasaponins A–C, and azukisaponins III and VI showed inhibition of nitric oxide production in LPS-activated RAW264.7 macrophages, with IC50 values ranging from 13?M to 24?M.
Publication date: Available online 7 November 2014 Source:Phytochemistry Author(s): Luka Mihajlovic , Jelena Radosavljevic , Lidija Burazer , Katarina Smiljanic , Tanja Cirkovic Velickovic Phenolic composition of Ambrosia artemisiifolia L. pollen and sub-pollen particles (SPP) aqueous extracts was determined, using a novel extraction procedure. Total phenolic and flavonoid content was determined, as well as the antioxidative properties of the extract. Main components of water-soluble pollen phenolics are monoglycosides and malonyl-mono- and diglycosides of isorhamnetin, quercetin and kaempferol, while spermidine derivatives were identified as the dominant polyamides. SPP are similar in composition to pollen phenolics (predominant isorhamnetin and quercetin monoglycosides), but lacking small phenolic molecules (<450Da). Ethanol-based extraction protocol revealed one-third lower amount of total phenolics in SPP than in pollen.For the first time in any pollen species, SPP and pollen phenolic compositions were compared in detail, with an UHPLC/ESI-LTQ-Orbitrap-MS–MS approach, revealing the presence of spermidine derivatives in both SPP and pollen, not previously reported in Ambrosia species.
Publication date: Available online 14 November 2014 Source:Phytochemistry Author(s): Nadine Meitinger , Daniel Geiger , Thierry W. Augusto , Rodrigo Maia de Pádua , Wolfgang Kreis The isomerization of 5-pregnene-3,20-dione into 4-pregnene-3,20-dione was investigated to shed further light on cardenolide biosynthesis and to characterize the enzymes involved in cardenolide formation. It was shown that the ?5-3-ketosteroid isomerase of Digitalis lanata, which catalyzes this isomerization, is an individual enzyme and not, as previously thought, associated with ?5-3?-hydroxysteroid dehydrogenase. The enzyme was purified by fractionated ammonium sulfate precipitation, hydrophobic interaction chromatography and gel filtration. The purification protocol resulted in a 68.1-fold enriched specific enzyme activity with a yield of 2.2%. After an additional chromatofocusing step the 3KSI activity appeared as a single protein band at 17kDa in SDS–PAGE. Plant 3KSI displayed similar properties to microbial 3-ketosteroid isomerases.
Publication date: Available online 5 November 2014 Source:Phytochemistry Author(s): Isabel C.F.R. Ferreira , Sandrina A. Heleno , Filipa S. Reis , Dejan Stojkovic , Maria João R.P. Queiroz , M. Helena Vasconcelos , Marina Sokovic Ganoderma genus comprises one of the most commonly studied species worldwide, Ganodermalucidum. However, other Ganoderma species have been also reported as important sources of bioactive compounds. Polysaccharides are important contributors to the medicinal properties reported for Ganoderma species, as demonstrated by the numerous publications, including reviews, on this matter. Yet, what are the chemical features of Ganoderma polysaccharides that have bioactivity? In the present manuscript, the chemical features of Ganoderma polysaccharides with reported antioxidant, antitumor and antimicrobial activities (the most studied worldwide) are analyzed in detail. The composition of sugars (homo- versus hetero-glucans and other polysaccharides), type of glycosidic linkages, branching patterns, and linkage to proteins are discussed. Methods for extraction, isolation and identification are evaluated and, finally, the bioactivity of polysaccharidic extracts and purified compounds are discussed. The integration of data allows deduction of structure–activity relationships and gives clues to the chemical aspects involved in Ganoderma bioactivity.
Publication date: November 2014 Source:Phytochemistry, Volume 107 Author(s): Li-Ping Kang , Ke-Lei Wu , He-Shui Yu , Xu Pang , Jie Liu , Li-Feng Han , Jie Zhang , Yang Zhao , Cheng-Qi Xiong , Xin-Bo Song , Chao Liu , Yu-Wen Cong , Bai-Ping Ma Sixteen steroidal saponins, including seven previously unreported compounds, were isolated from Tribulus terrestris. The structures of the saponins were established using 1D and 2D NMR spectroscopy, mass spectrometry, and chemical methods. They were identified as: 26-O-?-d-glucopyranosyl-(25R)-furost-4-en-2?,3?,22?,26-tetrol-12-one (terrestrinin C), 26-O-?-d-glucopyranosyl-(25R)-furost-4-en-22?,26-diol-3,12-dione (terrestrinin D), 26-O-?-d-glucopyranosyl-(25S)-furost-4-en-22?,26-diol-3,6,12-trione (terrestrinin E), 26-O-?-d-glucopyranosyl-(25R)-5?-furostan-3?,22?,26-triol-12-one (terrestrinin F), 26-O-?-d-glucopyranosyl-(25R)-furost-4-en-12?,22?,26-triol-3-one (terrestrinin G), 26-O-?-d-glucopyranosyl-(1?6)-?-d-glucopyranosyl-(25R)-furost-4-en-22?,26-diol-3,12-dione (terrestrinin H), and 24-O-?-d-glucopyranosyl-(25S)-5?-spirostan-3?,24?-diol-12-one-3-O-?-d-glucopyranosyl-(1?4)-?-d-galactopyranoside (terrestrinin I). The isolated compounds were evaluated for their platelet aggregation activities. Three of the known saponins exhibited strong effects on the induction of platelet aggregation.
Publication date: November 2014 Source:Phytochemistry, Volume 107 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.
Publication date: Available online 19 November 2014 Source:Phytochemistry Author(s): Veronica Alicia Yap , Bi-Juin Long , Kang-Nee Ting , Sandy Hwei-San Loh , Kien-Thai Yong , Yun-Yee Low , Toh-Seok Kam , Kuan-Hon Lim Hispidacine, an 8,4?-oxyneolignan featuring incorporation of an unusual 2-hydroxyethylamine moiety at C-7, and hispiloscine, a phenanthroindolizidine alkaloid, were isolated from the stem-bark and leaves of the Malaysian Ficus hispida Linn. Their structures were established by spectroscopic analysis. Hispidacine induced a moderate vasorelaxant activity in rat isolated aorta, while hispiloscine showed appreciable antiproliferative activities against MDA-MB-231, MCF-7, A549, HCT-116 and MRC-5 cell lines.
Publication date: November 2014 Source:Phytochemistry, Volume 107 Author(s): Mwafaq Ibdah , Anna Berim , Stefan Martens , Andrea Lorena Herrera Valderrama , Luisa Palmieri , Efraim Lewinsohn , David R. Gang The apple tree (Malus sp.) is an agriculturally and economically important source of food and beverages. Many of the health beneficial properties of apples are due to (poly)phenolic metabolites that they contain, 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 dihydrochalcone precursor, p-dihydrocoumaroyl-CoA (3), are unknown. To identify genes involved in the synthesis of these metabolites, existing genome databases of the Rosaceae were screened for apple genes with significant sequence similarity to Arabidopsis alkenal double bond reductases. Herein described are the isolation and characterization of a Malus hydroxycinnamoyl-CoA double bond reductase, which catalyzed the NADPH-dependent reduction of p-coumaroyl-CoA and feruloyl-CoA to p-dihydrocoumaroyl-CoA and dihydroferuloyl-CoA, respectively. Its apparent Km values for p-coumaroyl-CoA, feruloyl-CoA and NADPH were 96.6, 92.9 and 101.3?M, respectively. The Malus double bond reductase preferred feruloyl-CoA to p-coumaroyl-CoA as a substrate by a factor of 2.1 when comparing catalytic efficiencies in vitro. Expression analysis of the hydroxycinnamoyl-CoA double bond reductase gene revealed that its transcript levels showed significant variation in tissues of different developmental stages, but was expressed when expected for involvement in dihydrochalcone formation. Thus, the hydroxycinnamoyl-CoA double bond reductase appears to be responsible for the reduction of the ?,?-unsaturated double bond of p-coumaroyl-CoA, the first step of dihydrochalcone biosynthesis in apple tissues, and may be involved in the production of these compounds.
Publication date: Available online 14 November 2014 Source:Phytochemistry Author(s): Jian-Hong Yang , Jian-Xin Pu , Jin Wen , Xiao-Nian Li , Fei He , Jia Su , Yan Li , Han-Dong Sun Five 3,4-seco-cycloartane triterpenoids were isolated from the stems of Kadsura ananosma, two of which had rearranged 5/6 consecutive carbocycle rings C/D (trivially named ananosins A (1) and B (2)), one had a migrated CH3-18 (named ananosins C (3)), and two were analogs, ananosins D (4) and E (5). Their structures were characterized by comprehensive spectroscopic analysis, especially using 2D NMR spectra. A biogenetic pathway to 1 was proposed. These 5 compounds, together with 5 known analogs isolated from the same origin, were evaluated for their cytotoxicity against HL-60, SMMC-7721, A-549, PANC-1, and SK-BR-3 human cancer cells, but were inactive.
Publication date: November 2014 Source:Phytochemistry, Volume 107 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.
Publication date: November 2014 Source:Phytochemistry, Volume 107 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 S1–S4 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.
Publication date: November 2014 Source:Phytochemistry, Volume 107 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.
Publication date: Available online 13 November 2014 Source:Phytochemistry Author(s): Alexis Lavaud , Pascal Richomme , Julia Gatto , Marie-Christine Aumond , Cyril Poullain , Marc Litaudon , Ramaroson Andriantsitohaina , David Guilet Ten tocotrienol derivatives, i.e., amplexichromanols (1–10), were isolated from stem bark of Garcinia amplexicaulis Vieill. ex Pierre collected in Caledonia. The structures of the compounds 1–5 were determined to be chromanol derivatives substituted by a polyprenyl chain oxidized in terminal position. The remaining compounds 6–10 are the corresponding dimeric derivatives. Eleven known compounds, including xanthones, tocotrienol derivatives, triterpenes and phenolic compounds, were also isolated. Their structures were mainly determined using one and two-dimensional NMR and mass spectroscopy analysis. The compounds and some amplexichromanol molecules formerly isolated from G. amplexicaulis exhibited significant antioxidant activity against lipid peroxidation and in the ORAC assay.
Publication date: November 2014 Source:Phytochemistry, Volume 107 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: Paeoniasuffruticosa, Paeoniaqiui, Paeoniaostii, Paeoniarockii, Paeoniajishanensis, Paeoniadecomposita, Paeoniadelavayi, and Paeonialudlowii. 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.
Publication date: November 2014 Source:Phytochemistry, Volume 107 Author(s): Isabelle Pouny , Muriel Batut , Laure Vendier , Bruno David , Sirong Yi , François Sautel , Paola B. Arimondo , Georges Massiot Four alkaloids named hosieines A–D were isolated from the root and stem of Ormosia hosiei. Their flat structures were established by mass spectrometry and by a combination of NMR experiments. These molecules probably share a common biosynthetic origin with the lupin alkaloids but they differ in the formation of the last ring, being here part of a rare 2-azabicyclo[3.2.1]octane system. Their absolute configuration was determined by X-ray crystallography using CuK? radiation. As has been described for cytisine, they display a remarkable affinity towards neuronal nicotinic acetylcholine ?4?2 receptor.
Publication date: November 2014 Source:Phytochemistry, Volume 107 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.
Publication date: Available online 12 November 2014 Source:Phytochemistry Author(s): C.-L. Ho , Y.-C. Tan Basal stem rot (BSR) of oil palm roots is due to the invasion of fungal mycelia of Ganoderma species which spreads to the bole of the stem. In addition to root contact, BSR can also spread by airborne basidiospores. These fungi are able to break down cell wall components including lignin. BSR not only decreases oil yield, it also causes the stands to collapse thus causing severe economic loss to the oil palm industry. The transmission and mode of action of Ganoderma, its interactions with oil palm as a hemibiotroph, and the molecular defence responses of oil palm to the infection of Ganodermaboninense in BSR are reviewed, based on the transcript profiles of infected oil palms. The knowledge gaps that need to be filled in oil palm–Ganoderma molecular interactions i.e. the associations of hypersensitive reaction (HR)-induced cell death and reactive oxygen species (ROS) kinetics to the susceptibility of oil palm to Ganoderma spp., the interactions of phytohormones (salicylate, jasmonate and ethylene) at early and late stages of BSR, and cell wall strengthening through increased production of guaiacyl (G)-type lignin, are also discussed.
The molecular defence responses of oil palm to Ganoderma infection in basal stem rot are reviewed based on the transcript profiles of pathogenesis-related proteins in infected oil palms.
Publication date: November 2014 Source:Phytochemistry, Volume 107 Author(s): Liying Tang , Zhuju Wang , Hongwei Wu , Akihito Yokosuka , Yoshihiro Mimaki Six spirostanol glycosides (1–6) and 12 known compounds (7–18) were isolated from the underground parts of Dracaena thalioides (Agavaceae). Their structures were determined by spectroscopic analysis, including 2D NMR spectroscopic data, and chemical transformations. The isolated compounds were evaluated for cytotoxic activity against HL-60 human leukemia cells. Compounds 1, 3–6, and 8–18 showed cytotoxicity against HL-60 cells, of which 10, a bisdesmosidic spirostanol derivative, showed potent cytotoxicity against HL-60 cells with an IC50 value of 0.38?M and induced apoptosis in HL-60 cells.
Publication date: November 2014 Source:Phytochemistry, Volume 107 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.
Publication date: Available online 12 November 2014 Source:Phytochemistry Author(s): Jonathon Roepke , Gale G. Bozzo Kaempferol and quercetin 3-O-?-glucoside-7-O-?-rhamnoside (K3G7R and Q3G7R, respectively) are major flavonol bisglycosides accumulating in Arabidopsis thaliana with synergistic abiotic stresses (i.e., nitrogen deficiency and low temperature, NDLT). However, these molecules disappear rapidly during recovery from NDLT. Typically, catabolism of related chemicals relies on ?-glucosidase (BGLU) action. Evidence for flavonol 3-O-?-glucoside-7-O-?-rhamnoside BGLU activity is provided here. Major losses of Q3G7R and K3G7R coincided with an approximate 250% induction in flavonol 3-O-?-glucoside-7-O-?-rhamnoside BGLU activity within 2days of NDLT recovery relative to plants cultured under nitrogen sufficiency and high temperature (NSHT, control). QTOF-MS/MS established the product of Q3G7R hydrolysis in the presence of Arabidopsis cell free extracts was quercetin 7-O-?-rhamnoside. A phylogenetic analysis of the Arabidopsis glycoside hydrolase family 1 identified BGLU15 (At2g44450) and five other members that cluster with Fabaceae hydrolases known to attack isoflavones and isoflavonoids, which are structurally somewhat related to flavonol 3-O-?-glucoside-7-O-?-rhamnosides. Real time quantitative PCR analysis established a 300% higher expression of BGLU15 within 1day of the recovery from NDLT relative to control plants; lower or negligible changes in expression were evident for the remaining BGLUs. Recombinant thioredoxin-His6-tagged mature BGLU15 protein was expressed in Escherichia coli and purified to homogeneity. A comparison of a wide spectrum of ?-glucosides showed that recombinant BGLU15 preferentially hydrolyses the 3-O-?-glucosides of flavonols, but does not attack quercetin 3-O-?-rhamnoside, quercetin 3-O-?-galactoside and rutin. BGLU15 displayed the highest catalytic efficiency for Q3G7R and K3G7R yielding their respective 7-O-rhamnosides as products; flavonol 3-O-glucosides were also attacked, albeit with lower efficiency. Together, it appears the loss of flavonol 3-O-?-glucoside-7-O-?-rhamnosides in Arabidopsis is dependent upon the enzyme-mediated cleavage of the 3-O-? linked glucose moiety.
Publication date: November 2014 Source:Phytochemistry, Volume 107 Author(s): Rashmi Gaur , Mahendra P. Darokar , P.V. Ajayakumar , Ram Sajiwan Shukla , Rajendra Singh Bhakuni Biotransformation of antimalarial drug artemisinin by fungi Rhizopus stolonifer afforded three sesquiterpenoid derivatives. The transformed products were 1?-hydroxyartemisinin (3), 3.0%, a new compound, 10?-hydroxyartemisinin, 54.5% (4) and deoxyartemisinin (2) in 9% yield. The fungus expressed high-metabolism activity (66.5%). The chemical structures of the compounds were elucidated by 1D, 2D NMR spectrometry and mass spectral data. The major compound 10?-hydroxyartemisinin (4) was chemically converted to five new derivatives 5–9. All the compounds 3–9 were subjected for in vitro anti-malarial activity. 10?-Hydroxy-12?-arteether (8), IC50 at 18.29nM was found to be 10 times better active than its precursor 4 (184.56nM) and equipotent antimalarial with natural drug artemisinin whereas the ?-derivative 9 is 3 times better than 4 under in vitro conditions. Therefore, the major biotransformation product 4 can be exploited for further modification into new clinically potent molecules. The results show the versatility of microbial-catalyzed biotransformations leading to the introduction of a hydroxyl group at tertiary position in artemisinin in derivative (3).
Publication date: November 2014 Source:Phytochemistry, Volume 107 Author(s): Yogini Jaiswal , Zhitao Liang , Alan Ho , LaiLai Wong , Peng Yong , Hubiao Chen , Zhongzhen Zhao Aconite poisoning continues to be a major type of poisoning caused by herbal drugs in many countries. Nevertheless, despite its toxic characteristics, aconite is used because of its valuable therapeutic benefits.The aim of the present study was to determine the distribution of toxic alkaloids in tissues of aconite roots through chemical profiling. Three species were studied, all being used in traditional Chinese Medicine (TCM) and traditional Indian medicine (Ayurveda), namely: Aconitum carmichaelii, Aconitum kusnezoffii and Aconitum heterophyllum.Laser micro-dissection was used for isolation of target microscopic tissues, such as the metaderm, cortex, xylem, pith, and phloem, with ultra-high performance liquid chromatography equipped with quadrupole time-of-flight mass spectrometry (UHPLC–QTOF MS) employed for detection of metabolites. Using a multi-targeted approach through auto and targeted LC–MS/MS, 48 known compounds were identified and the presence of aconitine, mesaconitine and hypaconitine that are the biomarkers of this plant was confirmed in the tissues. These results suggest that the three selected toxic alkaloids were exclusively found in A. carmichaelii and A. kusnezoffii. The most toxic components were found in large A. carmichaelii roots with more lateral root projections, and specifically in the metaderm, cork and vascular bundle tissues. The results from metabolite profiling were correlated with morphological features to predict the tissue specific distribution of toxic components and toxicity differences among the selected species. By careful exclusion of tissues having toxic diester diterpenoid alkaloids, the beneficial effects of aconite can still be retained and the frequency of toxicity occurrences can be greatly reduced.Knowledge of tissue-specific metabolite distribution can guide users and herbal drug manufacturers in prudent selection of relatively safer and therapeutically more effective parts of the root. The information provided from this study can contribute towards improved and effective management of therapeutically important, nonetheless, toxic drug such as Aconite.
Publication date: November 2014 Source:Phytochemistry, Volume 107 Author(s): Elaine Wan Ling Chan , Alexander I. Gray , John O. Igoli , Sui Mae Lee , Joo Kheng Goh Galloylated flavonol rhamnosides identified as kaempferol-3-O-(2?,3?,4?-tri-O-galloyl)-?-l-rhamnopyranoside, quercetin-3-O-(3?,4?-di-O-galloyl)-?-l-rhamnopyranoside, and quercetin-3-O-(2?,3?,4?-tri-O-galloyl)-?-l-rhamnopyranoside, together with five known galloylated and non-galloylated flavonol rhamnosides, were isolated from leaves of Calliandra tergemina (L.) Benth. Their structures were established using spectroscopic methods and their antibacterial activities against methicillin-resistant Staphylococcus aureus (MRSA) were evaluated by a microdilution method.
Publication date: Available online 12 November 2014 Source:Phytochemistry Author(s): Md. Abul Hasnat , Mehnaz Pervin , Kyu Min Cha , Si Kwan Kim , Beong Ou Lim Ganoderma lucidum is a popular medicinal mushroom with anti-inflammatory potential. In the present study, the aim was to determine the anti-inflammatory effect and mode of action of G. lucidum grown on germinated brown rice (GLBR) in a mouse model of colitis. It was shown that GLBR suppressed the production of nitric oxide (NO) and prostaglandin E2 (PGE2) in lipopolysaccharide (LPS)-stimulated macrophages and decreased the expression of COX-2, TNF-?, iNOS, IL-1?, IL-6, and IL-10 mRNAs. GLBR also inhibited activation of p38, ERK, JNK, MAPKs, and nuclear factor kappa-B (NF-?B). In a mouse model of colitis, colonic mucosal injury was evaluated using macroscopic, biochemical, and histopathological testing. Disease activity index (DAI), macroscopic score, and histological score significantly decreased upon GLBR treatment. Moreover, immunofluorescence studies indicated that DSS activates nuclear translocation of NF-?B in colon tissue, which is attenuated by GLBR extract. These findings suggest that GLBR is protective against colitis via inhibition of MAPK phosphorylation and NF-?B activation.
Publication date: November 2014 Source:Phytochemistry, Volume 107 Author(s): Guo-Yuan Zhu , Li-Ping Bai , Liang Liu , Zhi-Hong Jiang Eight ring C-seco and ring-intact limonoids, and 25 known limonoids were isolated from the fruits of Melia toosendan (Meliaceae). Their structures were elucidated on the basis of extensive spectroscopic evidence including HRMS, 1D and 2D NMR spectroscopic data. A total of 29 isolated limonoids was evaluated for NF-?B activities. Among them, eight compounds significantly enhanced the TNF?-induced NF-?B luciferase activity at 10?M, while 10 compounds suppressed the NF-?B activation.
Publication date: Available online 31 October 2014 Source:Phytochemistry Author(s): Sachiko Sugimoto , Amira Samir Wanas , Tsutomu Mizuta , Katsuyoshi Matsunami , Mohamed Salah Kamel , Hideaki Otsuka Three aromatic glycosides (1–3), two sulfur and nitrogen-containing compound glucosides (4, 5), and one flavonoid glycoside (6) were isolated from the leaves of Ixora undulata. Their structures were established by extensive 1D, 2D NMR, and HRESIMS experiments, and structure 4 was further confirmed by single crystal X-ray diffraction analysis. Of the assayed compounds, 7, 11 and 12 showed strong inhibitory activity toward advanced glycation end-products formation with IC50 values of 86.0?M, 76.6?M and 98.6?M, respectively.
Publication date: Available online 31 October 2014 Source:Phytochemistry Author(s): Katerina Kokkotou , Efstathia Ioannou , Marianna Nomikou , Florian Pitterl , Ariadni Vonaparti , Eleni Siapi , Maria Zervou , Vassilios Roussis The global metabolic profile of Laurencia crude red algal extracts was addressed by applying high-throughput analytical techniques, namely UHPLC–PDA–HRMS and 2D HSQC NMR. An integrated platform including software tools and databases, such as Xcalibur, ToxID, ACD/Labs and MarinLit, has been developed to mine the complex analytical data towards the accelerated identification of known metabolites and the detection of new natural products at the early stages of phytochemical analysis. In parallel, a searchable ‘in-house’ Laurencia-focused NMR database incorporating chemical structures, NMR spectroscopic data and reported biological activities has been generated. The screening strategy has been developed as a tool to prioritize the crude extracts to be further subjected to phytochemical analysis by tracing the presence of new natural products among the pool of known compounds. The successful application of this integrated methodology in the crude extract of Laurencia chondrioides led to the rapid detection of two new C15 bromoallene acetogenins (1 and 2), which were subsequently isolated and characterized.
Publication date: Available online 11 November 2014 Source:Phytochemistry Author(s): Estelle Delort , Alain Jaquier , Erik Decorzant , Christian Chapuis , Alessandro Casilli , Eric Frérot The volatile constituents of the peel of three cultivars of Australian finger lime (Citrus australasica) were investigated: Alstonville, Judy’s Everbearing and Durham’s Emerald. Both qualitative and quantitative GC–MS analyses were performed on their peel solvent extract. The results showed that the unique phenotypes of finger lime are also correlated to unique molecular compositions. Each cultivar revealed a different chemotype: limonene/sabinene for cv. Alstonville, limonene/citronellal/isomenthone for cv. Judy’s Everbearing, and limonene/citronellal/ citronellol for cv. Durham’s Emerald. To the best of our knowledge, these chemotypes have never been reported in any other citrus species. Furthermore, the amounts of some volatile constituents (?-terpinene, ?-pinene, ?-pinene, citral), which are generally the major constituents besides limonene in lime species, were surprisingly low in the three cultivars. Comparative GC–MS analysis also showed that some volatile molecules tended to be specific to one cultivar and could therefore be considered as markers. Moreover six molecules were reported for the first time in a citrus extract and confirmed by synthesis. Heart-cutting enantioselective two-dimensional GC–MS was performed to determine the enantiomeric distribution of the major chiral constituents. The combined data on three finger lime cultivars gives evidence of their divergence from other citrus species.
Publication date: Available online 31 October 2014 Source:Phytochemistry Author(s): XingRong Peng , JieQing Liu , JianJun Xia , CuiFang Wang , XuYang Li , YuanYuan Deng , NiMan Bao , ZhiRun Zhang , MingHua Qiu Chemical investigation of the fruiting bodies of Ganoderma hainanense resulted in isolation of fourteen lanostane triterpenoids, including nine ganoderma acids and five ganoderma alcohols, together with five known compounds. Structural elucidation was determined using extensive spectroscopic technologies, Mosher’s method and X-ray single crystal diffraction. Three of the compounds showed inhibitory activities against HL-60, SMMC-7721, A-549 and MCF-7 cells with IC50 values of 15.0–40.0?M.
Publication date: Available online 29 October 2014 Source:Phytochemistry Author(s): Raquel Rosales , Irene Romero , Mª Isabel Escribano , Carmen Merodio , Mª Teresa Sanchez-Ballesta Dehydrins (DHNs), group II LEA (Late Embryogenesis Abundant) proteins, are among the most commonly observed proteins which accumulate in plants in response to cold and any other environmental factors, causing the dehydration of cells. In previous studies, we isolated a YSK2-type VvcDHN1a gene from table grapes (Vitis vinifera cv. Cardinal) which presented two spliced variants (the spliced, DHN1a_s and the unspliced, DHN1a_u). Their expression was induced by low temperature storage and CO2, although with different accumulation patterns. DHN1a_u codifies for a truncated YS protein lacking ?- and K-segments, which might affect its functionality. In this work, we expressed both DHN1a_s and DHN1a_u recombinant proteins in Escherichia coli. We carried out a number of in vitro assays to analyze the implications that ?- and K-segments have in the protective role of VvcDHN1 against different abiotic stresses and their antifungal activity against the fungal pathogen Botrytis cinerea. Our results showed that unlike DHN1a_u, DHN1a_s has a potent cryoprotective effect on lactate dehydrogenase activity, protects malate dehydrogenase against dehydration and partially inhibits B. cinerea growth. Moreover, the DHN1a promoter presented cis-regulatory elements related to cold and drought, as well as biotic stress-related elements. We also observed that both spliced variants interact weakly with DNA, suggesting that K-segments are not involved in DNA binding. Overall, this work highlights the crucial role of ?- and K-segments in DHNs function in plant response to abiotic stress showing for the first time, the potential role of the V. vinifera DHN1a_s in the protection against freezing and dehydration as well as inhibiting B. cinerea growth.
Publication date: Available online 29 October 2014 Source:Phytochemistry Author(s): N. Prota , R. Mumm , H.J. Bouwmeester , M.A. Jongsma The genus Persicaria is known to include species accumulating drimane sesquiterpenoids, but a comparative analysis highlighting the compositional differences has not been done. In this study, the secondary metabolites of both flowers and leaves of Persicariahydropiper, Persicariamaculosa and Persicariaminor, three species which occur in the same habitat, were compared. Using gas chromatography–mass spectrometry (GC–MS) analysis of extracts, overall 21/29 identified compounds in extracts were sesquiterpenoids and 5/29 were drimanes. Polygodial was detected in all species, though not in every sample of P. maculosa. On average, P. hydropiper flowers contained about 6.2mggFW?1 of polygodial, but P. minor flowers had 200-fold, and P. maculosa 100,000 fold lower concentrations. Comparatively, also other sesquiterpenes were much lower in those species, suggesting the fitness benefit to depend on either investing a lot or not at all in terpenoid-based secondary defences. For P. hydropiper, effects of flower and leaf development and headspace volatiles were analysed as well. The flower stage immediately after fertilisation was the one with the highest content of drimane sesquiterpenoids and leaves contained about 10-fold less of these compounds compared to flowers. The headspace of P. hydropiper contained 8 compounds: one monoterpene, one alkyl aldehyde and six sesquiterpenes, but none were drimanes. The potential ecological significance of the presence or absence of drimane sesquiterpenoids and other metabolites for these plant species are discussed.
Publication date: Available online 8 November 2014 Source:Phytochemistry Author(s): Nicolas J. Martin , Sara F. Ferreiro , Florent Barbault , Mael Nicolas , Gaël Lecellier , Christian Paetz , Marc Gaysinski , Eva Alonso , Olivier P. Thomas , Luis M. Botana , Phila Raharivelomanana In addition to the already reported nukuhivensiums 1 and 2, 11 indole alkaloids were isolated from the bark of the plant Rauvolfia nukuhivensis, growing in the Marquesas archipelago. The known sandwicine (3), isosandwicine (4), spegatrine (8), lochneram (9), flavopereirine (13) have been found in this plant together with the norsandwicine (5), isonorsandwicine (6), Nb-methylisosandwicine (7), 10-methoxypanarine (10), nortueiaoine (11), tueiaoine (12). The structure elucidation was performed on the basis of a deep exploration of the NMR and HRESIMS data as well as comparison with literature data for similar compounds. Norsandwicine, 10-methoxypanarine, tueiaoine, and more importantly nukuhivensiums, were shown to significantly induce a reduction of IKr amplitude (HERG current). Molecular modelling through docking was performed in order to illustrate this result.
Publication date: Available online 28 October 2014 Source:Phytochemistry Author(s): Philippe J. Eugster , Julien Boccard , Benjamin Debrus , Lise Bréant , Jean-Luc Wolfender , Sophie Martel , Pierre-Alain Carrupt The detection and early identification of natural products (NPs) for dereplication purposes require efficient, high-resolution methods for the profiling of crude natural extracts. This task is difficult because of the high number of NPs in these complex biological matrices and because of their very high chemical diversity. Metabolite profiling using ultra-high pressure liquid chromatography coupled to high-resolution mass spectrometry (UHPLC–HR-MS) is very efficient for the separation of complex mixtures and provides molecular formula information as a first step in dereplication. This structural information alone or even combined with chemotaxonomic information is often not sufficient for unambiguous metabolite identification. In this study, a representative set of 260 NPs containing C, H, and O atoms only was analysed in generic UHPLC–HR-MS profiling conditions. Two easy to use quantitative structure retention relationship (QSRR) models were built based on the measured retention time and on eight simple physicochemical parameters calculated from the structures. First, an original approach using several partial least square (PLS) regressions according to the phytochemical classes provided satisfactory results with an easy calculation. Secondly, a unique artificial neural network (ANN) model provided similar results on the whole set of NPs but required dedicated software. The retention prediction methods described in this study were found to improve the level of confidence of the identification of given analytes among putative isomeric structures. Its applicability was verified for the dereplication of NPs in model plant extracts.
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