Phytochemistry

Current research reports and chronological list of recent articles.


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

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

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

 - Phytochemical Analysis.

 - Phytochemistry Letters.

 - Phytochemistry Reviews.



Phytochemistry - Abstracts



A unique indolizinium alkaloid streptopertusacin A and bioactive bafilomycins from marine-derived Streptomyces sp. HZP-2216E

Publication date: December 2017
Source:Phytochemistry, Volume 144

Author(s): Xiufang Zhang, Lu Chen, Weiyun Chai, Xiao-Yuan Lian, Zhizhen Zhang

Streptopertusacin A, a unique indolizinium alkaloid existing as a zwitterion, and six bafilomycins including two previously undescribed ones of 21,22-en-bafilomycin D and 21,22-en-9-hydroxybafilomycin D were isolated from a culture of the seaweed-derived Streptomyces sp. HZP-2216E. Structures of these isolated compounds were determined based on extensive NMR spectroscopic analyses, HRESIMS and MS-MS data. The stereochemical assignments were achieved by NOE information, chemical degradation, Marfey's method, and electronic circular dichroism (ECD) calculation. Streptopertusacin A is the first example of this type of indolizinium alkaloid from microorganisms and showed moderate activity against the growth of methicillin-resistant Staphylococcus aureus (MRSA). 21,22-en-bafilomycin D and 21,22-en-9-hydroxybafilomycin D had potent activities in inhibiting the proliferation of glioma cells and the growth of MRSA.

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Datum: 24.09.2017


Preference of Arabidopsis thaliana GH3.5 acyl amido synthetase for growth versus defense hormone acyl substrates is dictated by concentration of amino acid substrate aspartate

Publication date: November 2017
Source:Phytochemistry, Volume 143

Author(s): Rebecca Mackelprang, Rachel A. Okrent, Mary C. Wildermuth

The GH3 family of adenylating enzymes conjugate acyl substrates such as the growth hormone indole-3-acetic acid (IAA) to amino acids via a two-step reaction of acyl substrate adenylation followed by amino acid conjugation. Arabidopsis thaliana GH3.5 was previously shown to be unusual in that it could adenylate both IAA and the defense hormone salicylic acid (SA, 2-hydroxybenzoate). Our detailed studies of the kinetics of GH3.5 on a variety of auxin and benzoate substrates provides insight into the acyl preference and reaction mechanism of GH3.5. For example, we found GH3.5 activity on substituted benzoates is not defined by the substitution position as it is for GH3.12/PBS3. Most importantly, we show that GH3.5 strongly prefers Asp as the amino acid conjugate and that the concentration of Asp dictates the functional activity of GH3.5 on IAA vs. SA. Not only is Asp used in amino acid biosynthesis, but it also plays an important role in nitrogen mobilization and in the production of downstream metabolites, including pipecolic acid which propagates defense systemically. During active growth, [IAA] and [Asp] are high and the catalytic efficiency (k cat/K m) of GH3.5 for IAA is 360-fold higher than with SA. GH3.5 is expressed under these conditions and conversion of IAA to inactive IAA-Asp would provide fine spatial and temporal control over local auxin developmental responses. By contrast, [SA] is dramatically elevated in response to (hemi)-biotrophic pathogens which also induce GH3.5 expression. Under these conditions, [Asp] is low and GH3.5 has equal affinity (K m) for SA and IAA with similar catalytic efficiencies. However, the concentration of IAA tends to be very low, well below the K m for IAA. Therefore, GH3.5 catalyzed formation of SA-Asp would occur, fine-tuning localized defensive responses through conversion of active free SA to SA-Asp. Taken together, we show how GH3.5, with dual activity on IAA and SA, can integrate cellular metabolic status via Asp to provide fine control of growth vs. defense outcomes and hormone homeostasis.

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Datum: 24.09.2017


Bioactive ent-kaurane diterpenoids from Isodon rubescens

Publication date: November 2017
Source:Phytochemistry, Volume 143

Author(s): Yuan-Yuan Zhang, Hua-Yi Jiang, Miao Liu, Kun Hu, Wei-Guang Wang, Xue Du, Xiao-Nian Li, Jian-Xin Pu, Han-Dong Sun

Seven previously undescribed 7,20-epoxy-ent-kaurane diterpenoids, isojiangrubesins A–G, along with seventeen known ones, were isolated from the aerial parts of Isodon rubescens. Their structures were characterized on the basis of spectroscopic methods and signal-crystal X-ray diffraction. All of these compounds were evaluated for their in vitro cytotoxicity against five human tumor cell lines (HL-60, SMMC-7721, A-549, MCF-7, and SW480). Four isolates exhibited significant inhibitory ability against all cell lines, with IC50 values ranging from 0.5 to 6.5 μM; They also strongly inhibited NO production in LPS-stimulated RAW264.7 cells.

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Datum: 24.09.2017


Outside Front Cover

Publication date: November 2017
Source:Phytochemistry, Volume 143










Datum: 24.09.2017


Molecular cloning and functional expression of Lewis type α1,3/α1,4-fucosyltransferase cDNAs from Mangifera indica L.

Publication date: December 2017
Source:Phytochemistry, Volume 144

Author(s): Takahiro Okada, Hideyuki Ihara, Ritsu Ito, Yoshitaka Ikeda

In higher plants, complex type N-glycans contain characteristic carbohydrate moieties that are not found in mammals. In particular, the attachment of the Lewis a (Lea) epitope is currently the only known outer chain elongation that is present in plant N-glycans. Such a modification is of great interest in terms of the biological function of complex type N-glycans in plant species. However, little is known regarding the exact molecular basis underlying their Lea expression. In the present study, we cloned two novel Lewis type fucosyltransferases (MiFUT13) from mango fruit, Mangifera indica L., heterologously expressed the proteins and structurally and functionally characterized them. Using an HPLC-based assay, we demonstrated that the recombinant MiFUT13 proteins mediate the α1,4-fucosylation of acceptor tetrasaccharides with a strict preference for type I-based structure to type II. The results and other findings suggest that MiFUT13s are involved in the biosynthesis of Lea containing glycoconjugates in mango fruits.

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Datum: 24.09.2017


Oleanane triterpenes with protein tyrosine phosphatase 1B inhibitory activity from aerial parts of Lantana camara collected in Indonesia and Japan

Publication date: December 2017
Source:Phytochemistry, Volume 144

Author(s): Delfly B. Abdjul, Hiroyuki Yamazaki, Wilmar Maarisit, Henki Rotinsulu, Defny S. Wewengkang, Deiske A. Sumilat, Magie M. Kapojos, Fitje Losung, Kazuyo Ukai, Michio Namikoshi

During the search for new protein tyrosine phosphatase (PTP) 1B inhibitors, EtOH extracts from the aerial parts of Lantana camara L. (lantana) collected at Manado (Indonesia) and two subtropical islands in Japan (Ishigaki and Iriomote Islands, Okinawa) exhibited potent inhibitory activities against PTP1B in an enzyme assay. Four previously undescribed oleanane triterpenes were isolated together with known triterpenes and flavones from the Indonesian lantana. The EtOH extracts of lantana collected in Ishigaki and Iriomote Islands exhibited different phytochemical profiles from each other and the Indonesian lantana. Triterpenes with a 24-OH group were isolated from the Indonesian lantana only. Five known triterpene compounds were detected in the Ishigaki lantana, and two oleanane triterpenes with an ether linkage between 3β and 25 were the main components together with five known triterpenes as minor components in the Iriomote lantana. The structures of previously undescribed compounds were assigned on the basis of their spectroscopic data. Among the compounds obtained in this study, oleanolic acid exhibited the most potent activity against PTP1B, and is used as a positive control in studies on PTP1B.

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Datum: 24.09.2017


Lanostane-type triterpenoids from the fruiting body of Ganoderma calidophilum

Publication date: November 2017
Source:Phytochemistry, Volume 143

Author(s): Sheng-Zhuo Huang, Qing-Yun Ma, Fan-Dong Kong, Zhi-Kai Guo, Cai-Hong Cai, Li-Li Hu, Li-Man Zhou, Qi Wang, Hao-Fu Dai, Wen-Li Mei, You-Xing Zhao

To search for active anti-cancer constituents in the fruiting body of Ganoderma calidophilum, we have successfully isolated four previously undescribed spiro-lactone lanostane triterpenoids (spiroganocalitones A-D), two previously undescribed lanostanoids (ganodecalones A and B) together with twenty-three known ones. The structures of the six previously undescribed compounds were elucidated based on 1D, 2D-NMR, and HRMS analyses. Ganoderone A showed moderate cytotoxic activity against K562, BEL7402, and SGC790 cell lines with IC50 values of 7.62, 6.28, and 3.55 μM, respectively.

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Datum: 24.09.2017


Six scalemic mixtures of 6-monosubstituted dihydrobenzophenanthridine alkaloids from Chelidonium majus and optically active structures of enantiomers

Publication date: December 2017
Source:Phytochemistry, Volume 144

Author(s): An-Jun Deng, Hai-Jing Zhang, Qian Li, Zhi-Hong Li, Zhi-Hui Zhang, Lian-Qiu Wu, Li Li, Hai-Lin Qin

Six pairs of previously undescribed 6-monosubstituted dihydrobenzophenanthridine alkaloids were separated as corresponding six scalemic mixtures from the aerial part of Chelidonium majus. The elucidation for the 2D structures of these alkaloids was achieved using regular spectroscopic and chemical methods. The assignment of scalemic-mixture nature was achieved using combined examinations of their NMR data, CD spectra, calculation of specific rotations, and chiral HPLC profiles. The identification for the relative configurations of alkaloids possessing two asymmetric carbons directly connected up by a rotatable sp 3-sp 3 carbon-carbon single bond was significantly facilitated by discussing the erythro and threo relative configurations defined by the mutuality of the orders of decreasing steric hindrances between the two sets of ligands linked to the two chiral centers. Two scalemic mixtures were assigned as (1′R,6R/1′S,6S)- and (1′S,6R/1′R,6S)-1-(dihydrochelerythrine-6-yl)ethanols, two as (1′R,6R)/(1′S,6S)- and (1′S,6R)/(1′R,6S)-1-(dihydrosanguinarine-6-yl)ethanols, one as (±)-ethyl 2-(dihydrosanguinarine-6-yl)acetate, and one as (±)-ethyl dihydrosanguinarine-6-carboxylate, respectively. The resolution of three scalemic mixtures was achieved and the absolute configurations of the three pairs of enantiomers were assigned via time-dependent Density Functional Theory calculations of electronic circular dichroism (ECD) data. The assignment for the absolute configurations of the other three scalemic mixtures was achieved via a chiral HPLC-UV/CD method plus analyzing their ECD data. The findings of this paper demonstrated that the relevant biochemical reactions concerning the construction of these 6-monosubstituted dihydrobenzophenanthridine alkaloids in the test plant are very nonselective. Scalemic mixture of (1′R,6R)/(1′S,6S)-1-(dihydrosanguinarine-6-yl)ethanol exhibited biological activity. It inhibited the growth of human MDA-MB-231 cell line at a moderate level with IC50 value of 5.12 μM.

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Datum: 24.09.2017


Ecophysiological strategies for growth under varying light and organic carbon supply in two species of green microalgae differing in their motility

Publication date: December 2017
Source:Phytochemistry, Volume 144

Author(s): Elly Spijkerman, Marcus Lukas, Alexander Wacker

Mixing events in stratified lakes result in microalgae being exposed to varying conditions in light and organic carbon concentrations. Stratified lakes consist of an upper illuminated strata and a lower, darker strata where organic carbon accumulates. Therefore, in this contribution we explore the importance of dissolved organic carbon for growth under various light intensities by measuring some ecophysiological adaptations in two green microalgae. We compared the non-motile Chlorella vulgaris with the flagellated Chlamydomonas acidophila under auto-, mixo-, and heterotrophic growth conditions. In both algae the maximum photosynthetic and growth rates were highest under mixotrophy, and both algae appeared inhibited in their phosphorus acquisition under heterotrophy. Heterotrophic conditions provoked the largest differences as C. vulgaris produced chlorophyll a in darkness and grew as well as in autotrophic conditions, whereas Chl. acidophila bleached and could not grow heterotrophically. Although the fatty acid composition of both phytoplankton species differed, both species reacted in a similar way to changes in their growth conditions, mainly by a decrease of C18:3n-3 and an increase of C18:1n-9 from auto- to heterotrophic conditions. The two contrasting responses within the group of green microalgae suggest that dissolved organic carbon has a high deterministic potential to explain the survival and behaviour of green algae in the deeper strata of lakes.

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Datum: 24.09.2017


Graphical Contents List

Publication date: November 2017
Source:Phytochemistry, Volume 143










Datum: 24.09.2017


Idesia polycarpa (Salicaceae) leaf constituents and their toxic effect on Cerura vinula and Lymantria dispar (Lepidoptera) larvae

Publication date: November 2017
Source:Phytochemistry, Volume 143

Author(s): Felix Feistel, Christian Paetz, Sybille Lorenz, Franziska Beran, Grit Kunert, Bernd Schneider

Phytochemical investigation of Idesia polycarpa (Salicaceae) resulted in the structure elucidation of nine previously undescribed phenolic natural products along with six known compounds. The compounds are structurally related to salicinoids that are known defense compounds from Salix and Populus species. The I. polycarpa diet was toxic, as shown in feeding experiments with larvae of Lymantria dispar, an herbivorous broadleaf tree generalist insect, and with larvae of Cerura vinula, a specialist adapted to poplar. The survival rate and mass gain of larvae was significantly lower when they fed on I. polycarpa leaves, compared to larvae fed on Populus nigra leaves. Potential reasons for the poor performance of both herbivores on I. polycarpa leaves are discussed.

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Datum: 24.09.2017


Specialized metabolites from the aerial parts of Centaurea polyclada DC.

Publication date: November 2017
Source:Phytochemistry, Volume 143

Author(s): Serdar Demir, Canan Karaalp, Erdal Bedir

The genus Centaurea L. (Asteraceae) is represented by 200 taxa in the flora of Turkey and several Centaurea species are used as herbal remedies against different conditions. Previous phytochemical investigations on this genus generally revealed the isolation of sesquiterpene lactones and flavonoid derivatives. In our continuous search on Centaurea genus, a phytochemical study was performed on Centaurea polyclada DC., an endemic of West Anatolia. Previously undescribed two sesquiterpene-amino acid conjugates, an elemane and an eudesmane derivative were isolated from the aerial parts of Centaurea polyclada, together with eight known compounds; two elemane derivatives, three flavonoids, a lignan, a phenolic glucoside and a phenylpropanoid glucoside. Structural elucidation of the compounds was based on spectroscopic evidence, including 1D and 2D NMR and high-resolution mass spectrometry, chemical degradation results and reference data comparison. Sesquiterpene-amino acid conjugates are representatives of an unusual group of sesquiterpenes, and elemane-amino acid conjugates are herein reported for the first time in nature.

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Datum: 24.09.2017


Diterpenoids from the roots of Croton dichogamus Pax

Publication date: December 2017
Source:Phytochemistry, Volume 144

Author(s): Areej Aldhaher, Moses Langat, Beth Ndunda, Denis Chirchir, Jacob O. Midiwo, Alice Njue, Sianne Schwikkard, Mark Carew, Dulcie Mulholland

Four previously undescribed diterpenoids including two crotofolanes, crotodichogamoin A and B, and two halimanes, crothalimene A and B, a new sesquiterpenoid, and fifteen previously reported compounds, including the crotofolane, crotohaumanoxide, the casbane, depressin, a further seven furanohalimane diterpenoids, three patchoulane and two further cadinane sesquiterpenoids and aleuritolic acid were isolated from the root of Croton dichogamus. Crotodichogamoin B is an important biosynthetic intermediate of the crotofolane class and this is the first report of patchoulene sesquiterpenoids from the genus. Compounds were tested at one concentration, 1 × 10−5 M, in the NCI59 cell one-dose screen but did not show significant activity snd were also evaluated for their cytotoxicity against Caco-2 cell lines using the neutral red assay. 10-epi-Maninsigin D reduced Caco-2 cell viability at 10, 30 and 100 μM, with values of decreased viability of 28%, 48% and 43% respectively. None of the other tested compounds showed significant activity.

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Datum: 24.09.2017


Cycloartane-type triterpene glycosides anopanins A-C with monoacyldigalactosylglycerols from Anodendron paniculatum

Publication date: December 2017
Source:Phytochemistry, Volume 144

Author(s): Viet Duc Ho, Thi Nhu Hanh Hoang, Quoc Hung Vo, Van Kiem Phan, Tuan Anh Le, Viet Ty Pham, Minh Hien Nguyen, Takeshi Kodama, Takuya Ito, Hiroyuki Morita, Ain Raal, Thi Hoai Nguyen

Three cycloartane-type triterpene glycosides (anopanins A–C), together with three known monoacyldigalactosylglycerols gingerglycolipids A–C and (2S)-1-O-palmitoyl-3-O-[α-d-galactopyranosyl-(1→6)-β-d-galactopyranosyl]-sn-glycerol, were isolated from the aerial parts of Anodendron paniculatum collected in Viet Nam. The chemical structures of the present compounds were elucidated by means of 1D and 2D NMR and HRESIMS spectroscopy, and by comparing to the reported data in the literature. These compounds did not show significant growth inhibitory activities (IC50 > 100 μg/mL) against the tested cancer cell lines LU-1 (lung adenocarcinoma), KB (epidermoid carcinoma), Hep-G2 (hepatoma cancer), MKN-7 (stomach cancer), and SW-480 (colon adenocarcinoma).

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Datum: 24.09.2017


Clovamide and clovamide-rich extracts of three Trifolium species as antioxidants and moderate antiplatelet agents in vitro

Publication date: November 2017
Source:Phytochemistry, Volume 143

Author(s): Joanna Kolodziejczyk-Czepas, Justyna Krzyżanowska-Kowalczyk, Malgorzata Sieradzka, Pawel Nowak, Anna Stochmal

This in vitro study provides a new insight into the phytochemical, antioxidant, antiplatelet and cytotoxic profiles of commercial trans-clovamide and clovamide-rich extracts, isolated from aerial parts of three Trifolium species (i.e. T. clypeatum L., T. obscurum Savi and T. squarrosum L.). Under inorganic experimental conditions, the EC50 for the investigated substances varied between 4.87 (clovamide) and 7.91 μg/ml (T. clypeatum) according to the DPPH assay. The most effective 1 mM ONOO scavenger was clovamide (IC50 = 19.29 μg/ml), and the weakest was the T. obsucurum extract (IC50 = 41.79 μg/ml). The antioxidant action of the examined substances (1–50 μg/ml) was also evaluated in blood plasma (under 100 μM ONOO-induced oxidative stress) using 3-nitrotyrosine, protein thiol groups, lipid hydroperoxides and thiobarbituric acid-reactive substances as biomarkers. All examined substances were more effective in limiting the oxidative damage to blood plasma components than the nitrative damage. Their anti-nitrative action was statistically significant only at the highest concentration (50 μg/ml). Measurements of platelet adhesion and aggregation found the compounds to have moderate antiplatelet properties of up to 20% inhibition of platelet adhesion at concentrations of 1–5 μg/ml. Additionally, clovamide and Trifolium extracts demonstrated no cytotoxicity towards blood platelets or peripheral blood mononuclear cells.

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Datum: 24.09.2017


Bioactive diterpenoids from Croton laevigatus

Publication date: December 2017
Source:Phytochemistry, Volume 144

Author(s): Jun-Sheng Zhang, Ya-Qi Tang, Jia-Luo Huang, Wei Li, Yi-Hong Zou, Gui-Hua Tang, Bo Liu, Sheng Yin

Eight previously undescribed diterpenoids, crolaevinoids A−H, including two halimanes, four clerodanes, and two laevinanes, along with six known analogues were isolated from the twigs of Croton laevigatus. The structures of the previously undescribed were elucidated by spectroscopic analysis, and their absolute configurations were determined by combination of a single crystal X-ray diffraction and CD analysis (exciton chirality and Rh2(OCOCF3)4-induced methods). Crolaevinoids A and B represent the first halimane diterpenoids with a unique lactone bridge between C-12 and C-17. All compounds were evaluated for their inhibitory effects on the nitric oxide (NO) production induced by lipopolysaccharide (LPS) in RAW264.7 macrophage cells. Furocrotinsulolide A and 3,4,15,16-diepoxy-cleroda-13(16),14-diene-12,17-olide exhibited pronounced inhibition of NO production with IC50 values of 10.4 ± 0.8 and 6.0 ± 1.0 μM, respectively, being more potent than the positive control, quercetin (IC50 = 13.1 ± 1.9 μM).

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Datum: 24.09.2017


Phenylpropanoid profiling reveals a class of hydroxycinnamoyl glucaric acid conjugates in Isatis tinctoria leaves

Publication date: December 2017
Source:Phytochemistry, Volume 144

Author(s): Thi-Kieu-Oanh Nguyen, Arash Jamali, Eric Grand, Kris Morreel, Paulo Marcelo, Eric Gontier, Rebecca Dauwe

The brassicaceous herb, Isatis tinctoria, is an ancient medicinal plant whose rosette leaf extracts have anti-inflammatory and anti-allergic activity. Brassicaceae are known to accumulate a variety of phenylpropanoids in their rosette leaves acting as antioxidants and a UV-B shield, and these compounds often have pharmacological potential. Nevertheless, knowledge about the phenylpropanoid content of I. tinctoria leaves remains limited to the characterization of a number of flavonoids. In this research, we profiled the methanol extracts of I. tinctoria fresh leaf extracts by liquid chromatography – mass spectrometry (LC-MS) and focused on the phenylpropanoid derivatives. We report the structural characterization of 99 compounds including 18 flavonoids, 21 mono- or oligolignols, 2 benzenoids, and a wide spectrum of 58 hydroxycinnamic acid esters. Besides the sinapate esters of malate, glucose and gentiobiose, which are typical of brassicaceous plants, these conjugates comprised a large variety of glucaric acid esters that have not previously been reported in plants. Feeding with 13C6-glucaric acid showed that glucaric acid is an acyl acceptor of an as yet unknown acyltransferase activity in I. tinctoria rosette leaves. The large amount of hydroxycinnamic acid derivatives changes radically our view of the woad metabolite profile and potentially contributes to the pharmacological activity of I. tinctoria leaf extracts.

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Datum: 24.09.2017


Indoline alkaloids from Tabernaemontana contorta with cancer chemopreventive activity

Publication date: December 2017
Source:Phytochemistry, Volume 144

Author(s): Joseph Thierry Ndongo, Joséphine Ngo Mbing, Michel Feussi Tala, Aymeric Monteillier, Dieudonné Emmanuel Pegnyemb, Muriel Cuendet, Hartmut Laatsch

Two bisindoline alkaloids, contortarine A, 16-epi-pleiomutinine and a reaction product of pleiomutinine, namely N 4-chloromethyl-pleiomutinine, were isolated from the roots of Tabernaemontana contorta Stapf. together with five known compounds: pleiomutinine, 1-carbomethoxy-β-carboline, strictosidine lactam, pleiocarpamine, and pleiocarpine. The structures and relative configuration of these alkaloids were determined by extensive 1D and 2D NMR, and MS measurements. The absolute configuration of these compounds was determined by comparison of experimental and calculated ECD spectra. Among the isolated compounds, contortarine A, 1-carbomethoxy-β-carboline and strictosidine lactam presented cancer chemopreventive properties through either quinone reductase (QR) induction with CD values of 16.0 ± 2.5, 30.2 ± 6.1 and 23.1 ± 4.6 μM, respectively, while pleiomutinine and 16-epi-pleiomutinine displayed the inhibition of TNF-α induced NF-κB activity with IC50 at 11.7 ± 2.6 and 3.4 ± 1.1 μM, respectively.

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Datum: 24.09.2017


Isolation and characterization of non-sulfated and sulfated triterpenoid saponins from Fagonia indica

Publication date: November 2017
Source:Phytochemistry, Volume 143

Author(s): Nayab Kanwal, Achyut Adhikari, Abdul Hameed, Rahman M. Hafizur, Syed Ghulam Musharraf

Seven previously undescribed, sulfated triterpenoid glycosides, named nayabin A-G along with a known triterpenoid glycoside were isolated from the whole plant of Fagonia indica. Their structures were elucidated through spectral studies including 1D- (1H and 13C), 2D-NMR spectroscopy (HSQC, HMBC, COSY and NOESY), and mass spectrometry (ESI-MS/MS). β- D -Glucopyranosyl 3β-hydroxy-23-O-β- D -glucopyranosyloxy-taraxast-20-en-28-oate, a known compound exerts glucose-dependent insulin secretory activity, which seems to exhibit a decreased risk of drug-induced hypoglycemia and may offer distinct advantages as anti-diabetic agent.

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Datum: 24.09.2017


Editorial Board/Publication Information

Publication date: November 2017
Source:Phytochemistry, Volume 143










Datum: 24.09.2017


Oleanane-type triterpene saponins from Calendula stellata

Publication date: December 2017
Source:Phytochemistry, Volume 144

Author(s): Meryem Lehbili, Abdulmagid Alabdul Magid, Ahmed Kabouche, Laurence Voutquenne-Nazabadioko, Amin Abedini, Hamid Morjani, Thomas Sarazin, Sophie C. Gangloff, Zahia Kabouche

Five previously undescribed bisdesmosidic triterpenoid saponins named calendustellatosides A-E, along with fifteen known compounds were isolated from the 70% ethanol whole plant extract of Calendula stellata Cav. (Asteraceae). Their structures were determined by 1D- and 2D-NMR spectroscopy as well as high resolution mass spectrometry and acid hydrolysis. The saponins comprised oleanolic acid, echinocystic acid, morolic acid or mesembryanthemoidigenic acid as the aglycones and saccharide moieties at C-3 and C-28. Like most Calendula saponins, the sugar moiety linked at C-3 was either β-d-glucose or β-d-glucuronic acid which could be substituted at C-3 by a β-d-galactose and/or C-2 by a supplementary β-d-galactose or a β-d-glucose. The sugar moiety linked to C-28 was determined as β-d-glucose. The antibacterial evaluation of compounds 120 by bioautography on Staphylococcus aureus followed by the determination of MIC values of active compounds by serial dilution technique against 5 bacteria revealed that; calendustellatoside D was the most active against Enterococcus faecalis with an antibacterial effect comparable to antibiotics. The cytotoxic activities of isolated compounds were evaluated against fibrosarcoma cell line (HT1080) and human lung cancer cell line (A549). Calendustellatosides B and D exhibited a low cytotoxic activity against HT1080 cell line with IC50 values of 47 ± 0.6 and 39 ± 0.5 μM, respectively.

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Datum: 24.09.2017


Phytochemistry of European Primula species

Publication date: November 2017
Source:Phytochemistry, Volume 143

Author(s): Paola S. Colombo, Guido Flamini, Graziella Rodondi, Claudia Giuliani, Laura Santagostini, Gelsomina Fico

The genus Primula is the largest among the Primulaceae and is widespread mainly in the cold and temperate regions of the Northern Hemisphere. Since the beginning of the Twentieth century, several studies on the phytochemical composition of different species of Primula have been carried out. The main constituents examined were tissue and epicuticular flavonoids and saponins, which are of therapeutic significance. Only in recent years studies of the volatiles emitted by leaves and flowers have been carried out as well, but they are restricted to a small number of species. Only a few authors have documented the morphology and function of glandular trichomes in relation to the production of flavonoids and volatile organic compounds (VOCs). The use of Primula in folk medicine is described in the literature. Investigation of the biological and pharmacological activities of Primula are reported. This study aims at providing a collection of publications on the genus Primula along with a critical revision of literature data. It focuses on the possible taxonomic significance of the secondary metabolites and on their ecological role as attractors for pollinators and deterrents against herbivores and parasites, in order to build the base for further studies.

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Datum: 24.09.2017


The study of flavonolignan association patterns in fruits of diverging Silybum marianum (L.) Gaertn. chemotypes provides new insights into the silymarin biosynthetic pathway

Publication date: December 2017
Source:Phytochemistry, Volume 144

Author(s): Tommaso Martinelli, Anne Whittaker, Stefano Benedettelli, Andrea Carboni, Jadwiga Andrzejewska

Silymarin is the phytochemical with medicinal properties extracted from Silybum marianum (L.) Gaertn. fruits. Yet, little information is available about silymarin biosynthesis. Moreover, the generally accepted pathway, formulated thus far, is not in agreement with actual experimental measurements on flavonolignan contents. The present work analyses flavonolignan and taxifolin content in 201 S. marianum samples taking into consideration a wide phenotypic variability. Two stable chemotypes were identified: one characterized by both high silychristin and silybin content (chemotype A) and another by a high silydianin content (chemotype B). Through the correlation analysis of samples divided according to chemotype, it was possible to construct a simplified silymarin biosynthetic pathway that is sufficiently versatile in explaining experimental results responding to the actually unresolved questions about this process. The proposed pathway highlights that three separate and equally sized metabolite pools exist, namely: diastereoisomers A (silybin A plus isosilybin A), diastereoisomers B (silybin B plus isosilybin B) and silychristin. In both A and B diastereoisomers pools, isosilybin A and isosilybin B always represent a given amount of the metabolite flux through the specific metabolite pool suggesting the possible involvement of dirigent protein-like enzymes. We suggest that chemotype B possesses a complete silymarin biosynthetic pathway in which silydianin biosynthesis is enzymatically controlled. On the contrary, chemotype A is probably a natural mutant unable to biosynthesize silydianin. The present simplified pathway for silymarin biosynthesis will constitute an important tool for the further understanding of the reactions that drive flavonolignan biosynthesis in S. marianum.

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Datum: 24.09.2017


Genome-wide screening of Oryza sativa ssp. japonica and indica reveals a complex family of proteins with ribosome-inactivating protein domains

Publication date: November 2017
Source:Phytochemistry, Volume 143

Author(s): Pieter Wytynck, Pierre Rougé, Els J.M. Van Damme

Ribosome-inactivating proteins (RIPs) are cytotoxic enzymes capable of halting protein synthesis by irreversible modification of ribosomes. Although RIPs are widespread they are not ubiquitous in the plant kingdom. The physiological importance of RIPs is not fully elucidated, but evidence suggests a role in the protection of the plant against biotic and abiotic stresses. Searches in the rice genome revealed a large and highly complex family of proteins with a RIP domain. A comparative analysis retrieved 38 RIP sequences from the genome sequence of Oryza sativa subspecies japonica and 34 sequences from the subspecies indica. The RIP sequences are scattered over different chromosomes but are mostly found on the third chromosome. The phylogenetic tree revealed the pairwise clustering of RIPs from japonica and indica. Molecular modeling and sequence analysis yielded information on the catalytic site of the enzyme, and suggested that a large part of RIP domains probably possess N-glycosidase activity. Several RIPs are differentially expressed in plant tissues and in response to specific abiotic stresses. This study provides an overview of RIP motifs in rice and will help to understand their biological role(s) and evolutionary relationships.

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Datum: 24.09.2017


Previously undescribed fridooleanenes and oxygenated labdanes from the brown seaweed Sargassum wightii and their protein tyrosine phosphatase-1B inhibitory activity

Publication date: December 2017
Source:Phytochemistry, Volume 144

Author(s): Anusree Maneesh, Kajal Chakraborty

Previously undescribed fridooleanene triterpenoids 2α-hydroxy-(28,29)-frido-olean-12(13), 21(22)-dien-20-propyl-21-hex-4′(Z)-enoate, 2α-hydroxy-(28,29)-frido-olean-12(13), 21(22)-dien-20-prop-2(E)-en-21-butanoate and oxygenated labdane diterpenoids 2α-hydroxy-8(17), (12E), 14-labdatriene, 3β, 6β, 13α-tri hydroxy 8(17), 12E, 14-labdatriene were purified from the ethyl acetate-methanol and dichloromethane fractions of the air-dried thalli of Sargassum wightii (Sargassaceae), a brown seaweed collected from the Gulf-of-Mannar of Penninsular India. Inhibitory potential of Δ12 oleanenes towards protein tyrosine phosphatase-1B, the critical regulator of insulin-receptor activity were found to be significantly greater (IC50 0.1 × 10−2 and 0.09 × 10−2 mg/mL, respectively) than the standard sodium metavanadate (IC50 0.31 × 10−2 mg/mL). Fridooleanene triterpenoids displayed greater antioxidant activities (IC50DPPH 0.16–0.18 mg/mL) than the commercially available antioxidants, butylated hydroxytoluene and α-tocopherol (IC50DPPH 0.25 and 0.63 mg/mL, respectively). In general, the oxygenated labdane diterpenoids displayed significantly lesser antioxidant and tyrosine phosphatase-1B inhibitory properties than those exhibited by the fridooleanenes. Bioactivities of the titled compounds were primarily determined by the electronic and lipophilic parameters and not by the steric descriptors. Molecular docking simulations and kinetic studies were employed to describe the tyrosine phosphatase-1B inhibitory mechanism. The previously undescribed fridooleanene triterpenoids might be used as potential anti-hyperglycaemic pharmacophore leads to reduce the risk of elevated postprandial glucose levels.

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Datum: 24.09.2017


Benzoylsalicylic acid derivatives as defense activators in tobacco and Arabidopsis

Publication date: November 2017
Source:Phytochemistry, Volume 143

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

Systemic acquired resistance (SAR) is a long lasting inducible whole plant immunity often induced by either pathogens or chemical elicitors. Salicylic acid (SA) is a known SAR signal against a broad spectrum of pathogens in plants. In a recent study, we have reported that benzoylsalicylic acid (BzSA) is a SAR inducer in tobacco and Arabidopsis plants. Here, we have synthesized BzSA derivatives using SA and benzoyl chlorides of various moieties as substrates. The chemical structures of BzSA derivatives were elucidated using Infrared spectroscopy (IR), Nuclear magnetic spectroscopy (NMR) and High-resolution mass spectrometer (HRMS) analysis. The bioefficacy of BzSA derivatives in inducing defense response against tobacco mosaic virus (TMV) was investigated in tobacco and SA abolished transgenic NahG Arabidopsis plants. Interestingly, pre-treatment of local leaves of tobacco with BzSA derivatives enhanced the expression of SAR genes such as NPR1 [Non-expressor of pathogenesis-related (PR) genes 1], PR and other defense marker genes (HSR203, SIPK, WIPK) in systemic leaves. Pre-treatment of BzSA derivatives reduced the spread of TMV infection to uninfected areas by restricting lesion number and diameter both in local and systemic leaves of tobacco in a dose-dependent manner. Furthermore, pre-treatment of BzSA derivatives in local leaves of SA deficient Arabidopsis NahG plants induced SAR through AtPR1 and AtPR5 gene expression and reduced leaf necrosis and curling symptoms in systemic leaves as compared to BzSA. These results suggest that BzSA derivatives are potent SAR inducers against TMV in tobacco and Arabidopsis.

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Datum: 24.09.2017


Chemodiversity of tryptamine-derived alkaloids in six Costa Rican Palicourea species (Rubiaceae–Palicoureeae)

Publication date: November 2017
Source:Phytochemistry, Volume 143

Author(s): Andreas Berger, Elias Tanuhadi, Lothar Brecker, Johann Schinnerl, Karin Valant-Vetschera

We report 14 harmala and tryptamine-iridoid alkaloids with various tri-, tetra- and pentacyclic cores from leaves and stem bark of six species of the large and complex neotropical genus Palicourea. Among them is the previously undescribed compound deoxostrictosamide which is related to strictosamide, a key intermediate in camptothecin biosynthesis. In addition, we describe the occurrence of 1,2,3,4-tetrahydronorharman-1-one for the first time within Rubiaceae and ophiorine A and B, two alkaloids with an unusual core bearing a betaine function and a zwitterion as new for the genus. Although the other compounds are already known from other species, their degree of structural diversity highlights the remarkable biosynthetic capabilities of the genus Palicourea. Furthermore, the present paper provides additional support for the hypothesis that tryptamine-iridoid alkaloids represent a distinct chemosystematic feature for the genus Palicourea.

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Datum: 24.09.2017


Fatty acid profiling and multivariate analysis in the genus Leucas reveals its nutritional, pharmaceutical and chemotaxonomic significance

Publication date: November 2017
Source:Phytochemistry, Volume 143

Author(s): Ashish Kumar Choudhary, P. Sunojkumar, Girish Mishra

Genus Leucas with about 41 species found in India, is an Asian genus with separation from its close relatives in Africa based on phylogenetic evidence. Present study represents the only comprehensive phytochemical investigation on this genus. We have analyzed the seed fatty acid compositions of 26 species and five varieties of Leucas for nutritional, pharmaceutical and chemotaxonomic perspectives. The fatty acids and their composition in seeds of Leucas species, collected from different geographical regions in India, were analyzed by gas chromatography and mass spectrometry. Significant variations have been observed in fatty acid profiles among species and their varieties. We observed major fatty acids as palmitic, stearic, oleic, linoleic and laballenic acid; whereas myristic, palmitoleic, cis-vaccenic, linolenic, eicosanoic, eicosenoic, phlomic and docosanoic acid were detected in minor quantities. Laballenic and phlomic acids are unusual allenic fatty acids found in few Lamiaceae members from order Lamiales. Laballenic acid, a proven molecule of pharmaceutical importance, was observed in all the Leucas species studied. Three species of Leucas; L. helianthimifolia, L. ciliata var. vestita and L. hirta were found to contain ≥40% laballenic acid and can act as potential source for isolation of pharmaceutical compounds. This study also reports the presence of another allenic fatty acid, phlomic acid, in several Leucas species. Principal component analysis and hierarchical cluster analysis showed a distinct separation among the species based on abundance of similar fatty acids. The fatty acid profile appears to be overlapping at higher level and does not support separation of Asian Leucas from its African relatives and the inclusion of Asian taxa in morphologic sections. However, hierarchical clustering of L. helianthimifolia, L. ciliata var. vestita and L. hirta supported treatment under the morphologic section Astrodon. Multivariate analysis on the chemometric data also supported this cluster as the most prominent source of medicinally useful laballenic acid. Based on the FAs profile, a reconsideration of species boundaries in L. ciliata and L. marrubioides species complex is proposed.

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Datum: 24.09.2017


NMR-based identification of the major bioactive molecules from an Italian cultivar of Lycium barbarum

Publication date: December 2017
Source:Phytochemistry, Volume 144

Author(s): Annalisa Lopatriello, Rosario Previtera, Simona Pace, Markus Werner, Luigi Rubino, Oliver Werz, Orazio Taglialatela-Scafati, Martino Forino

Lycium barbarum (Solanaceae), long known to the traditional Chinese medicine because of its many health-promoting effects, has of late spread widely across the Western hemisphere, mainly on account of the nutritional richness in vitamins, minerals and antioxidant metabolites of its fruits. Data on bioactive metabolites from fruits and leaves, which are commonly consumed in soups and salads, are scarce and sometimes even contradictory. By means of NMR, the present study identified the specialised products contained in an Italian cultivar of L. barbarum. Kaempeferol, caffeic acid, 3,4,5-trihydroxycinnamic acid and 5-hydroxyferulic acid were found in fresh fruits; rutin and chlorogenic acid were detected in leaves and flowers; also, a previously undescribed N,N-dicaffeoylspermidine derivative was identified in flowers, while N-feruloyltyramine derivatives, for which interesting anti-inflammatory properties have been reported, turned out to be the major bioactive molecules in stems. The plethora of the detected bioactive molecules amplifies the nutraceutical value of berries and leaves and prompts the exploitation of L. barbarum flowers and pruned stems as sources of beneficial compounds.

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Datum: 24.09.2017


Annotinolide F and lycoannotines A–I, further Lycopodium alkaloids from Lycopodium annotinum

Publication date: November 2017
Source:Phytochemistry, Volume 143

Author(s): Yu Tang, Juan Xiong, Yike Zou, Wei Wang, Chao Huang, Hai-Yan Zhang, Jin-Feng Hu

Seven lycopodine-type (annotinolide F and lycoannotines A–F), two lycodine-type (lycoannotines G and H), and one fawcettimine-type (lycoannotine I) previously undescribed naturally occurring Lycopodium alkaloids together with thirteen known ones were isolated from the whole plant of Lycopodium annotinum. Their structures and absolute configurations were determined by extensive spectroscopic methods, single-crystal X-ray diffraction, chemical transformation, and electronic circular dichroism (ECD) calculations. Among the isolates, annotinolide F, lycoannotines A and B are unusual 7,8-seco-lycopodane derivatives, and annotinolide F even further possesses a rare 8,5-lactone framework through a lactonization after the C-7/C-8 bond cleavage. Lycoannotine C is an uncommon 8,15-seco lycopodine-type alkaloid, whereas lycoannotine I represents the first example of a naturally occurring C-9/N bond cleavage product of fawcettimine-type alkaloid. Among them, only lycoannotine I was found to show considerable anti-butyrylcholinesterase (anti-BuChE) activity.

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Datum: 24.09.2017


Roscotanes and roscoranes: Oxygenated abietane and pimarane diterpenoids from Kaempferia roscoeana

Publication date: November 2017
Source:Phytochemistry, Volume 143

Author(s): Jutatip Boonsombat, Chulabhorn Mahidol, Pornsuda Chawengrum, Nanthawan Reuk-Ngam, Nitirat Chimnoi, Supanna Techasakul, Somsak Ruchirawat, Sanit Thongnest

Eight previously undescribed ditepenoids, including four oxygenated abietanes (roscotanes A-D) and four oxygenated pimaranes (roscoranes A-D), along with twelve known diterpenoids were isolated from the whole plants of Kaempferia roscoeana. Their structures were elucidated by extensive spectroscopic analysis, and the structure of roscotane A was further confirmed by single crystal X-ray diffraction analysis. Most isolated compounds were evaluated for their antimicrobial and antimalarial activities.

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Datum: 24.09.2017


Evaluation of Asteraceae herbal extracts in the management of diabetes and obesity. Contribution of caffeoylquinic acids on the inhibition of digestive enzymes activity and formation of advanced glycation end-products (in vitro)

Publication date: November 2017
Source:Phytochemistry, Volume 143

Author(s): Vítor Spínola, Paula C. Castilho

The study was performed to assess, for the first time, the in vitro anti-diabetic potential of ten Asteraceae plant extracts to inhibit the activity of digestive enzymes (α-amylase, α-, β-glucosidases and lipase) responsible for hydrolysis/digestion of sugar and lipids. Prevention of advanced glycation end-products (AGEs) formation was evaluated in bovine serum albumin/ribose glycation reaction model. The phytochemical profiles and caffeoylquinic acids (CQAs) contents were determined for the methanolic extract of each plant. Analyzed plant extracts exhibited significant inhibitory activity against key digestive enzymes linked to type II diabetes and obesity. A strong inhibition was observed for glucosidases and mild activity towards amylase and lipase (compared to reference compounds). Moreover, some extracts exhibited potent ability to prevent formation of AGEs, implicated in some diabetic complications. Caffeoylquinic acids were dominant in all plant extracts and findings demonstrate that these compounds are the most relevant hypoglycemic and anti-glycation agents. From the obtained results, Argyranthemum pinnatifidum, Helichrysum melaleucum, and Phagnalon lowei are good candidates for further development of phyto-pharmaceutical preparations as complementary therapy for diabetes and obesity control.

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Datum: 24.09.2017


The oxidative stress in allelopathy: Participation of prenyllipid antioxidants in the response to juglone in Chlamydomonas reinhardtii

Publication date: December 2017
Source:Phytochemistry, Volume 144

Author(s): Beatrycze Nowicka, Andrzej Żądło, Bartosz Pluciński, Jerzy Kruk, Paulina Kuczyńska

Allelopathy is a phenomenon, where one species releases compounds able to inhibit the growth of other species. Juglone, 5-hydroxy-1,4-naphtoquinone, is an allelochemical produced by walnut trees. The main mode of juglone toxicity is the formation of semiquinone radicals, able to reduce O2 to superoxide. Prenyllipid antioxidants such as tocopherol and plastoquinone are important for antioxidant defense in photosynthetic organisms. Here we assess their participation in the response to juglone. The impact of 20 μM juglone on the content of photosynthetic pigments and prenyllipid antioxidants in green microalga Chlamydomonas reinhardtii was measured over an incubation period of 7.5 h in low light and over 40 min under high light or in darkness. The decrease in pigment and prenyllipid content, accompanied by an increase in lipid hydroperoxides was observed over a longer incubation period with juglone. Simultaneous exposure to high light and juglone led to a pronounced decrease in carotenoids and prenyllipids, while there was no decrease in high light alone and no decrease or only a slight decrease in the series with juglone alone. The fact that semiquinone radicals are generated in juglone-exposed cells was confirmed using EPR spectroscopy. This article also shows that C. reinhardtii may be a suitable model for studies on some modes of phytotoxic action of allelochemicals.

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Datum: 24.09.2017


In situ mass spectrometry monitoring of fungal cultures led to the identification of four peptaibols with a rare threonine residue

Publication date: November 2017
Source:Phytochemistry, Volume 143

Author(s): Vincent P. Sica, Evan R. Rees, Huzefa A. Raja, José Rivera-Chávez, Joanna E. Burdette, Cedric J. Pearce, Nicholas H. Oberlies

Peptaibols are an intriguing class of fungal metabolites due both to their wide range of reported bioactivities and to the structural variability that can be generated by the exchange of variable amino acid building blocks. In an effort to streamline the discovery of structurally diverse peptaibols, a mass spectrometry surface sampling technique was applied to screen the chemistry of fungal cultures in situ. Four previously undescribed peptaibols, all containing a rare threonine residue, were identified from a fungal culture (MSX53554), which was identified as Nectriopsis Maire (Bionectriaceae, Hypocreales, Ascomycota). These compounds not only increased the known threonine-containing peptaibols by nearly 20%, but also, the threonine residue was situated in a unique place compared to the other reported threonine-containing peptaibols. After the initial in situ detection and characterization, a large-scale solid fermentation culture was grown. The four peptaibols were isolated and characterized by mass spectrometry. In addition, one of the peptaibols was fully characterized by NMR and amino acid analysis using Marfey's reagent and exhibited moderate in vitro anticancer activity.

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Datum: 24.09.2017


Piperidine alkaloids from Alocasia macrorrhiza

Publication date: November 2017
Source:Phytochemistry, Volume 143

Author(s): Wenjie Huang, Xiaomin Yi, Jianying Feng, Yihai Wang, Xiangjiu He

Six previously undescribed piperidine alkaloids were isolated from the rhizomes of Alocasia macrorrhiza (L.) Schott. Their structures were elucidated based on 1D and 2D NMR, IR, HR-ESI-MS spectroscopic analysis and the application of a modified Mosher method. All isolated alkaloids were evaluated for cytotoxicity against five human cancer cell lines (CNE-1, Detroit 562, Fadu, MGC-803, and MCF-7) using the MTT method. Only one compound exhibited cytotoxic effects against Detroit 562, Fadu, and MCF-7 cell lines with IC50 values less than 10 μM.

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Datum: 24.09.2017


Flavonoids, alkaloids from the seeds of Crotalaria pallida and their cytotoxicity and anti-inflammatory activities

Publication date: November 2017
Source:Phytochemistry, Volume 143

Author(s): Xiu-Ren Hu, Gui-Xin Chou, Cheng-Gang Zhang

Three flavonoids, cropalliflavones A–C, including two homoisoflavonoids with rare skeletons; three previously undescribed alkaloids, usaramine-N-oxide and cropallins A-B; and sixteen known compounds, were isolated from the seeds of Crotalaria pallida Ait. The absolute configurations of cropalliflavone A and usaramine-N-oxide were established by an ECD calculation and X-ray crystallography, respectively. Additionally, cropalliflavone B showed anti-proliferative activity against the MCF-7 cell line with an IC50 value of 6.77 μM, and cropalliflavone C showed anti-inflammatory activity, with an IC50 value of 16.07 μM.

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Datum: 24.09.2017


Early biotic stress detection in tomato (Solanum lycopersicum) by BVOC emissions

Publication date: December 2017
Source:Phytochemistry, Volume 144

Author(s): Tina Kasal-Slavik, Julia Eschweiler, Einhard Kleist, Roland Mumm, Heiner E. Goldbach, Alexander Schouten, Jürgen Wildt

We investigated impacts of early and mild biotic stress on Biogenic Volatile Organic Compounds (BVOC) emissions from tomato in order to test their potential for early (biotic) stress detection. Tomato plants were exposed to two common fungal pathogens, Botrytis cinerea and Oidium neolycopesici and the sap-sucking aphid Myzus persicae. Furthermore, plants were exposed to methyl jasmonate (MeJA) in order to identify BVOC emissions related to activation of jasmonic acid (JA) signalling pathway. These emissions where then used as a reference for identifying active JA signalling pathway in plants at early stages of biotic stress. After infection by the necrotrophic fungus B. cinerea, changes in BVOC emissions indicated that tomato plants had predominantly activated the jasmonic acid (JA) signalling pathway. The plants were able to modify their defence pathways in order to overcome fungal infection. When tomato plants were infected with the biotrophic fungus O. neolycopersici, only minor changes in BVOC emissions were observed with additional emissions of the sesquiterpene α-copaene. α-copaene emissions allowed the identification of general biotic stress in the plants, without pinpointing the actual triggered defence pathway. BVOC emissions during M. persicae attack had changed before the occurrence of visual symptoms. Despite low infestation rates, plants emitted methyl salicylate indicating activation of the SA-mediated defence pathway.

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Datum: 24.09.2017


Cytotoxic lanostane triterpenoids from the fruiting bodies of Piptoporus betulinus

Publication date: November 2017
Source:Phytochemistry, Volume 143

Author(s): Zeynep Tohtahon, Jingjing Xue, Jianxin Han, Yushuang Liu, Huiming Hua, Tao Yuan

Chemical investigation of a bioactive methanolic extract of the fruiting bodies of Piptoporus betulinus led to the isolation of five previously undescribed lanostane triterpenoids named piptolinic acids A−E, as well as five known lanostane triterpenoids. Their structures were elucidated on the basis of 1D and 2D NMR spectroscopic and HRESIMS analysis. Piptolinic acid A with an unusual moiety (3-hydroxy-4-methoxycarbonyl-3-methylbutyryloxy) at C-3 exhibited comparable cytotoxic activity against human promyelocytic leukemia cell line HL-60 (IC50 = 1.77 μM) and human acute monocytic leukemia cell line THP-1 (IC50 = 8.21 μM) to those of positive control, fluorouracil (IC50 = 6.38 and 4.41 μM, respectively).

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Datum: 24.09.2017


Depsidones and an α-pyrone derivative from Simpilcillium sp. PSU-H41, an endophytic fungus from Hevea brasiliensis leaf

Publication date: November 2017
Source:Phytochemistry, Volume 143

Author(s): Praphatsorn Saetang, Vatcharin Rukachaisirikul, Souwalak Phongpaichit, Sita Preedanon, Jariya Sakayaroj, Suparerk Borwornpinyo, Sawinee Seemakhan, Chatchai Muanprasat

Nine previously undescribed depsidones (simplicildones A-I) and one previously undescribed α-pyrone (simplicilopyrone) were isolated from the endophytic fungus Simplicillium sp. PSU-H41 along with 11 known compounds. Their structures were established by extensive spectroscopic analysis. Simplicildone A and known botryorhodine C displayed weak antibacterial against Staphylococcus aureus with equal MIC values of 32 μg/mL. Additionally, botryorhodine C was active against methicillin-resistant S. aureus with the same MIC value. Simplicildone C exhibited weak antifungal activity against Cryptococcus neoformans with an MIC value of 32 μg/mL. In addition, simplicildones A and C and botryorhodine C were noncytotoxic against noncancerous Vero cells.

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Datum: 24.09.2017


Lepistatins A–C, chlorinated sesquiterpenes from the cultured basidiomycete Lepista sordida

Publication date: November 2017
Source:Phytochemistry, Volume 143

Author(s): Hahk-Soo Kang, So-Ae Ji, So-Hyun Park, Jong-Pyung Kim

Three new chlorinated sesquiterpenes, named lepistatins A–C, were isolated from the culture broth of Basidiomycete Lepista sordida. The structures were determined by the analysis of spectroscopic data including HREIMS and 1D and 2D NMR. The absolute configuration of lepistatin B was determined by comparing the specific rotation and circular dichroism spectrum with those of known structurally related compounds bearing the same chiral carbon. The structures of lepistatins A–C feature the indanone core structure, but differ from other indanone-containing sesquiterpenes of fungal origin by the alkyl substitution pattern. This indicates that lepistatins A–C probably possess a new sesquiterpene scaffold derived from the common precursor, trans-humulyl cation, by an alternative cyclization.

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Datum: 24.09.2017


Phytochemical study of Juglans regia L. leaves

Publication date: December 2017
Source:Phytochemistry, Volume 144

Author(s): Sebastian Schwindl, Birgit Kraus, Jörg Heilmann

A methanolic extract of Juglans regia L. leaves was fractioned by various chromatographic techniques yielding a total of 40 metabolites belonging to megastigmane, tetralone, phenylpropanoid, neolignane and juglone glycosides. Ten unknown megastigmane glucoside derivatives (juglanionosides A-K, 110) and six unknown tetralone glucoside derivatives (juglanosides J-O, 1116) together with 24 known compounds - among them 16 described for the first time in Juglans - were isolated. As characteristic structural feature, the previously undescribed compounds showed acylation of the sugar units with sinapic, ferulic, coumaric, benzoic or salicylic acid. Their chemical structures were elucidated on the basis of 1D and 2D NMR techniques, HRESIMS as well as CD spectroscopy. Absolute stereochemistry was revealed by mild alkaline hydrolysis and comparison of CD and polarimetric data to literature values.

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Datum: 24.09.2017


Prenylated purine alkaloids from seeds of Gleditsia japonica

Publication date: November 2017
Source:Phytochemistry, Volume 143

Author(s): Yui Harauchi, Tadashi Kajimoto, Emi Ohta, Hiroyuki Kawachi, Aya Imamura-Jinda, Shinji Ohta

Three previously undescribed isoguanine glycosides with an N 3-prenyl group, designated locustoside B, saikachinoside B, and saikachinoside C, have been isolated from the seed of Gleditsia japonica Miquel (Fabaceae) along with two known compounds, locustoside A and saikachinoside A. Their structures were determined from spectroscopic data and X-ray crystallographic analysis. The inhibitory activity against acid phosphatase was evaluated.

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Datum: 24.09.2017


Isoflavones and anti-inflammatory constituents from the fruits of Psoralea corylifolia

Publication date: November 2017
Source:Phytochemistry, Volume 143

Author(s): Chiang-Hsiang Chen, Tsong-Long Hwang, Li-Chai Chen, Tsung-Hsien Chang, Chun-Sheng Wei, Jih-Jung Chen

The fruits of Psoralea corylifolia, known as Psoraleae Fructus (Buguzhi in Chinese), are traditionally used for the treatment of spermatorrhea, nephritis, asthma, pollakiuria, and various inflammatory diseases. Three previously undescribed isoflavone derivatives, 7-O-methylcorylifol A, 7-O-isoprenylcorylifol A, and 7-O-isoprenylneobavaisoflavone, have been isolated from the fruits of P. corylifolia, together with 9 known compounds. The structures of these compounds were determined through spectroscopic and MS analyses. Among the isolated compounds, 7-O-methylcorylifol A and psoralen exhibited potent inhibition (IC50 values ≤ 10.89 μM) of superoxide anion generation by human neutrophils in response to N-formyl-L-methionyl-L-leucyl-L-phenylalanine/cytochalasin B (fMLP/CB). 7-O-Isoprenylcorylifol A, 7-O-isoprenylneobavaisoflavone, and 12,13-dihydro-12,13-epoxybakuchiol inhibited fMLP/CB-induced elastase release with IC50 values ≤ 14.30 μM. In addition, 7-O-isoprenylcorylifol A, bakuchiol, 12,13-dihydro-12,13-epoxybakuchiol, and psoralidin showed potent inhibition with IC50 values ≤ 36.65 μM, against lipopolysaccharide (LPS)-induced nitric oxide (NO) generation.

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Datum: 24.09.2017


Bio-active maneonenes and isomaneonene from the red alga Laurencia obtusa

Publication date: November 2017
Source:Phytochemistry, Volume 143

Author(s): Nahed O. Bawakid, Walied M. Alarif, Ali I. Ismail, Mohamed E. El-Hefnawy, Khalid O. Al-Footy, Sultan S. Al-Lihaibi

Three previously undescribed compounds, maneonenes and isomaneonene derivatives; in addition to five known compounds, two cuparene, one chamigrene, and two cis-maneonenes were isolated from the Red Sea red alga Laurencia obtusa. The chemical structures of all unknown metabolites were characterized employing spectroscopic methods and then were further confirmed by single crystal X-ray analysis. Jeddahenyne A has C-5-C-12 etheric linkage and C-13-C-14 carbon-carbon double bond; Jeddahenyne B has in addition to the aforementioned etheric linkage a C-13 carbonyl function and absence of halogenation, unusual features for the maneonenes while 12-debromo-12-methoxy isomaneonene A shows unrecorded methoxylation at C-12. The apoptosis-inducing or inhibiting effect of both compounds on apoptosis of peripheral blood neutrophils was studied.

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Datum: 24.09.2017


Phytotoxic triterpene saponins from Bellis longifolia, an endemic plant of Crete

Publication date: December 2017
Source:Phytochemistry, Volume 144

Author(s): Maria I. Stavropoulou, Apostolis Angelis, Nektarios Aligiannis, Eleftherios Kalpoutzakis, Sofia Mitakou, Stephen O. Duke, Nikolas Fokialakis

In a study of 62 plant species of the Cretan flora for their phytotoxic activity, plants were extracted successively with CH2Cl2, MeOH and H2O. Phytotoxicity evaluation of the 240 extracts was performed against Lactuca sativa L. and Agrostis stolonifera L.. The MeOH extract of Bellis longifolia was the most phytotoxic. Bioassay-guided fractionation revealed that a fraction consisting mainly of saponins was the most effective. Separation of the saponins was performed using initially a step-gradient Centrifugal Partition Chromatography (CPC). Investigation of the active fraction led to the isolation and structure elucidation of three previously undescribed triterpene saponins, 3-O-β-D-fucopyranosyl polygalacic acid, 28-O-α-L-rhamnopyranosyl-(1 → 2)-β-D-fucopyranosyl polygalacic acid and 3-O-β-D-fucopyranosyl-2α,3β,23-trihydroxyolean-12-en-28-oic acid, which were present as the main phytotoxic compounds of the methanol extract. Two triterpenes, polygalacic acid and bellisonic acid and four kaempferol glucosides, as well as chlorogenic acid were also isolated. 3-O-β-D-fucopyranosyl polygalacic acid and 3-O-β-D-fucopyranosyl-2α,3β,23-trihydroxyolean-12-en-28-oic acid had phytotoxic activity similar to some commercial herbicides (IC50 values of ca. 25 μM) against duckweed (Lemna paucicostata).

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Datum: 24.09.2017


Antiproliferative metabolites from the Northern African endemic plant Daucus virgatus (Apiaceae)

Publication date: November 2017
Source:Phytochemistry, Volume 143

Author(s): Alì Snene, Carmina Sirignano, Daniela Rigano, Carmen Formisano, Ridha El Mokni, Giuseppe Ercolano, Hatem Dhaouadi, Angela Ianaro, Saoussen Hammami, Orazio Taglialatela-Scafati

Chemical analysis of the dichloromethane fraction obtained from aerial parts of the Northern African endemic plant Daucus virgatus led to the isolation of three previously undescribed sesquiterpenoids, namely the daucane vaginatin B, a eudesmane and the elemane elemavirgolide, along with five known metabolites. The structures of these compounds were determined by a detailed MS and NMR analysis and they were evaluated for antiproliferative activity against three human cell lines, A375 (melanoma), MCF-7 (breast adenocarcinoma), and HACAT (keratinocyte). The phytoalexin 6-methoxymellein revealed a previously unreported antiproliferative activity, while the eudesmane and the elemane derivatives exhibited a selective activity (SI = 11.1 and 3.3, respectively) against melanoma tumor cell lines.

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Datum: 24.09.2017


Editorial Board/Publication Information

Publication date: October 2017
Source:Phytochemistry, Volume 142










Datum: 24.09.2017


Outside Front Cover

Publication date: October 2017
Source:Phytochemistry, Volume 142










Datum: 24.09.2017


Comparative studies of cutins from lime (Citrus aurantifolia) and grapefruit (Citrus paradisi) after TFA hydrolysis

Publication date: December 2017
Source:Phytochemistry, Volume 144

Author(s): Brenda Liliana Hernández Velasco, Daniel Arrieta-Baez, Pedro Iván Cortez Sotelo, Juan Vicente Méndez-Méndez, Blanca Margarita Berdeja Martínez, Mayra Beatriz Gómez-Patiño

Grapefruit and lime cutins were analyzed and compared in order to obtain information about their cutin architecture. This was performed using a sequential hydrolysis, first with trifluoroacetic acid to remove most of the polysaccharides present in the cutins, followed by an alkaline hydrolysis in order to obtain the main aliphatic compounds. Analysis by CPMAS 13C NMR and ATR FT-IR of the cutins after 2.0 M TFA revealed that grapefruit cutin has independent aliphatic and polysaccharide domains while in the lime cutin these components could be homogeneously distributed. These observations were in agreement with an AFM analysis of the cutins obtained in the hydrolysis reactions. The main aliphatic compounds were detected and characterized as 16-hydroxy-10-oxo-hexadecanoic acid and 10,16-dihydroxyhexadecanoic acid. These were present in grapefruit cutin at 35.80% and 21.86% and in lime cutin at 20.44% and 40.36% respectively.

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Datum: 24.09.2017


Graphical Contents List

Publication date: October 2017
Source:Phytochemistry, Volume 142










Datum: 24.09.2017






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