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



Mechanistic insight in potential dual role of sinigrin against Helicoverpa armigera

Publication date: January 2018
Source:Phytochemistry, Volume 145

Author(s): Aniruddha R. Agnihotri, Chaitanya V. Hulagabali, Anmol S. Adhav, Rakesh S. Joshi

The adverse effect of glucosinolates on diverse phytophagous insects is well documented, but its impact on insect physiology has remained enigmatic. Here we report insights into detrimental effects of plant glucosinolate molecule, sinigrin, on Helicoverpa armigera growth and development. In-silico screening of multiple glucosinolates predicted sinigrin as one of the potential inhibitor of H. armigera cathepsin B and L. Insects fed on sinigrin containing diet showed significantly reduced growth (20–30%), delayed pupation (10–15%), decreased fecundity (50–80%) and developmental abnormalities. Further, sinigrin showed 50–60% inhibition of ex-vivo cathepsin like activity which might be a reason for growth and development related abnormalities. In-vitro and mass spectrometry studies highlighted the cytotoxicity caused due to the hydrolysis of sinigrin, into toxic isothiocyanates, in presence of H. armigera whole body extract. In conclusion, insect cathepsin inhibition and isothiocyanate mediated cytotoxicity lead to the dual adverse effect of sinigrin on H. armigera.

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Datum: 24.11.2017


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: 24.11.2017


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: 24.11.2017


α-Keto tetrahydrofuran lignan glucosides from the Bangladeshi medicinal plant Terminalia citrina inhibit estradiol (E2) induced proliferation in cancer cells

Publication date: January 2018
Source:Phytochemistry, Volume 145

Author(s): Md. Abdul Muhit, Kaoru Umehara, Hiroshi Noguchi

EtOAc extract from the leaves of Terminalia citrina collected in Bangladesh were separated, and seven previously undescribed α-keto tetrahydrofuran lignan glucosides (terminalosides Q to W) were isolated and characterized. NOESY analysis of 1H NMR spectra and ECD spectroscopic data analysis revealed the absolute stereochemistry of the tetrahydrofuran ring of the isolated constituents as being a (7S,8R,8′S)- configuration in terminalosides Q to U and a (7R,8R,8′S)- configuration in terminalosides V and W. All of the isolated compounds were evaluated for their estrogenic and anti-estrogenic properties using two types of estrogen-responsive human breast cancer cell lines (MCF-7 and T47D). Terminaloside R, which has a dioxymethylene group in its aromatic ring, inhibited 90% of estradiol-enhanced cell proliferation in T47D and MCF-7 cells at concentrations of 0.01 μM and 0.1 μM, respectively. On the other hand, terminaloside T, the analogous compound which has two oxymethyl groups in place of dioxymethylene, suppressed 90% of cell proliferation selectively in T47D cells at a concentration of 0.01 μM. However, terminaloside W, the 7R-stereoisomer of terminaloside R, only showed moderate activity.

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Datum: 24.11.2017


Neo-clerodane diterpenoids from the whole plants of Scutellaria formosana

Publication date: January 2018
Source:Phytochemistry, Volume 145

Author(s): Xin Chen, Wenhao Chen, Guangying Chen, Changri Han, Johnny J. He, Xueming Zhou, Zhangxin Yu, Chunyan Dai, Xiaoping Song

Scuteformoids A-J, ten previously undescribed neo-clerodane diterpenoids along with one known analogue, were isolated from petroleum ether soluable fraction of the whole plants of Scutellaria formosana. The differences among these compounds are the substituents and stereochemistry at C-13. Their structures were elucidated by 1D and 2D NMR experiments, and the absolute configurations of Scuteformoids A, C, E, F, and I were further confirmed by single-crystal X-ray diffraction. Scuteformoids A, C, D, F, H, and I were evaluated for their inhibitory effects against HIV lytic replication and cytotoxic activities. All of them showed weak anti-HIV activities, with EC50 values ranging from 48.24 to 79.17 μg/mL.

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Datum: 24.11.2017


Diterpenoids from Croton crassifolius include a novel skeleton possibly generated via an intramolecular [2+2]-photocycloaddition reaction

Publication date: January 2018
Source:Phytochemistry, Volume 145

Author(s): Maosong Qiu, Jing Jin, Lian Zhou, Wen Zhou, Yinxiang Liu, Qinglong Tan, Di Cao, Zhongxiang Zhao

Five previously undescribed terpenoids (cracrosons D-H), including three clerodane diterpenoids, together with 16 known diterpenoids were isolated from Croton crassifolius (Euphorbiaceae). Cracroson D features a previously undescribed carbon skeleton with an unprecedented cyclobutane ring. Their structures, including their absolute configurations, were elucidated using spectroscopic and single-crystal X-ray diffraction analyses along with CD calculations. A plausible biogenetic pathway for cracroson D is also proposed, which was supported by the experimental results. Additionally, all of the compounds were evaluated in vitro for cytotoxicity against T24 and A549 cells using the CCK-8 method.

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Datum: 24.11.2017


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: 24.11.2017


Lovastatin analogues and other metabolites from soil-derived Aspergillus terreus YIM PH30711

Publication date: January 2018
Source:Phytochemistry, Volume 145

Author(s): Qiang Wang, Ya-Bin Yang, Xue-Qiong Yang, Cui-Ping Miao, Yi-Qing Li, Shi-Xi Liu, Na Luo, Zhong-Tao Ding, Li-Xing Zhao

Eight previously undescribed metabolites including of lovastatin analogues, a pair of diastereoisomers, a cyclopentenone dimer, and three polyketides were isolated from the culture of Aspergillus terreus YIM PH30711. Two types of unprecedented skeletons, benzene-cyclopentanone complex and linear polyketide, and an unusual dimer structure were determined by spectral analysis. Compound, 3α-hydroxy-3,5-dihydromonacolin L showed moderate activity against HMG-CoA reductase, with an inhibition ratio of 34% at the concentration of 50 μM, while lovastatin and dihydromonacolin K ethyl ester presented much stronger activity against HMGR with inhibition rates of 85% and 90% at the concentration of 50 μM, respectively. Aspereusin A was active against AChE with a ratio of 62% at the concentration of 50 μM, while its stereomers did not showed obvious inhibition (<10%). The configuration at C-4 of these three diastereoisomers was crucial in the inhibition against AChE, and the β-orientation of substituted methoxyl acrylic acid should be beneficial to the combining with AChE.

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Datum: 24.11.2017


Investigation of the flavan-3-ol patterns in willow species during one growing-season

Publication date: January 2018
Source:Phytochemistry, Volume 145

Author(s): Stefan Wiesneth, Gregor Aas, Jörg Heilmann, Guido Jürgenliemk

Flavonoids, proanthocyanidins (PAs) and salicylic alcohol derivatives are the main groups of ingredients in Salix needed as defensive tools and signal molecules, but have also pharmaceutical importance. The present study investigated total PA content, complete PA pattern, the oligomeric/total PAs quotient and the contents of catechin and epicatechin during one growing-season for the leaves and this year's sprouts in ten willows (Salix pentandra L. ♂, S. alba L. ♂, S. fragilis L. ♀, S. caprea L. ♂ & ♀, S. cinerea L. ♂, S. caprea x cinerea ♂, S. daphnoides Vill. ♂ & ♀ and S. purpurea L. ♀; all Salicaceae). Comparison of the different species revealed distinct seasonal fluctuations of the oligomeric and polymeric PA fractions, but the contents of both groups always developed in the same direction. All willows prefer the synthesis of PAs with DP-2 - DP-4 within the oligomeric fraction (DP-2 – DP-10) and species with rather low PA contents like S. purpurea (0.1–2.6 mg/g) as well as species with rather high PA contents like S. alba (3.8–14.7 mg/g) were found. Only slight gender specific differences could be observed for both sexes of S. daphnoides and S. caprea. The PA pattern of the hybrid S. caprea x cinerea seems to be influenced by both parents. Thus, the accumulation of the oligomeric PAs accorded to S. caprea and the polymeric PAs matched S. cinerea resulting in an overall depression of PAs in the sprouts and a varying seasonal trend in the leaves. In contrast, the content of catechin remained high and seemed to be not influenced in the hybrid. Although only one individual of each Salix species could be considered in this screening study, the present results demonstrate the variability of the flavan-3-ol pattern within the genus Salix but also some preliminary correlations could be observed. Future studies with more Salix species will provide more insights into chemotaxonomic correlations.

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Datum: 24.11.2017


Triterpenoids with antiplatelet aggregation activity from Ilex rotunda

Publication date: January 2018
Source:Phytochemistry, Volume 145

Author(s): Bao Yang, Jin-Ping Zhu, Li Rong, Jing Jin, Di Cao, Hui Li, Xing-Hong Zhou, Zhong-Xiang Zhao

Phytochemical studies on the barks of Ilex rotunda Thunb. had resulted in the isolation of seven previously undescribed triterpenoids, rotundinosides E-K, along with sixteen known ones. The structures of previously undescribed compounds were elucidated on the basis of extensive spectroscopic analysis and the sugar moieties were further identified by HPLC and GC after acid hydrolysis. Among the isolates, rotundinoside F featured a rare triterpene-phenylpropanoid hybrid structure and rotundinoside H was an uncommon triterpene saponin with α-linked glucopyranosyl moiety at C-3. The antiplatelet aggregation of all compounds were evaluated against ADP induced rat platelet aggregation in vitro, and five compounds exhibited moderate inhibitory effects with IC50 values ranging from 22.4 to 32.8 μM.

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Datum: 24.11.2017


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: 24.11.2017


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: 24.11.2017


Chrysin: Sources, beneficial pharmacological activities, and molecular mechanism of action

Publication date: January 2018
Source:Phytochemistry, Volume 145

Author(s): Renuka Mani, Vijayakumar Natesan

In recent years, public and scientific interest in plant flavonoids has tremendously increased because of their postulated health benefits. This review was mainly focuses on the flavone chrysin (5,7-dihydroxyflavone), which occurs naturally in many plants, honey, and propolis. A number of in vitro and in vivo studies have revealed the therapeutic effects of chrysin against various diseases. In general, chrysin exhibits many biological activities and pharmacological effects, including antioxidant, anti-inflammatory, anticancer, and antiviral activities. Moreover, many studies have reported on the bioavailability of chrysin. Because of its compromised bioavailability and enhanced protein stability, chrysin solid lipid nanoparticle (SLN) synthesis avoids proteolytic degradation and sustained release of drug delivery. To clarify the mechanism of action of chrysin, researchers have investigated the structural binding relationship of chrysin through the docking computation method.

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Datum: 24.11.2017


A set of biogenetically interesting polyhalogenated acetogenins from Ptilonia magellanica

Publication date: January 2018
Source:Phytochemistry, Volume 145

Author(s): Amalia B. Gallardo, Mercedes Cueto, Ana R. Díaz-Marrero, José M. de la Rosa, Victor Fajardo, Aurelio San-Martín, José Darias

Ptilonines A−F, pyranosylmagellanicus D−E and magellenediol are previously undescribed acetogenins isolated from the red alga Ptilonia magellanica. Their structures were determined from spectroscopic evidence. The absolute configuration of the known pyranosylmagellanicus A, was established by derivatization with (R)− and (S)−α−methoxy −α−phenylacetic acids (MPA). Ptilonines exhibit an unusual halogenation pattern, that may confer evolutionary advantages to Ptilonia magellanica, for which a biogenetic origin is proposed. The antimicrobial effect of some of these compounds was evaluated.

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Datum: 24.11.2017


Genus-wide variation in foliar polyphenolics in eucalypts

Publication date: December 2017
Source:Phytochemistry, Volume 144

Author(s): Karen J. Marsh, Carsten Kulheim, Simon P. Blomberg, Andrew H. Thornhill, Joseph T. Miller, Ian R. Wallis, Dean Nicolle, Juha-Pekka Salminen, William J. Foley

Many studies quantify total phenolics or total tannins, but understanding the ecological role of polyphenolic secondary metabolites requires at least an understanding of the diversity of phenolic groups present. We used UPLC-MS/MS to measure concentrations of different polyphenol groups - including the four most common tannin groups, the three most common flavonoid groups, and quinic acid derivatives - in foliage from 628 eucalypts from the genera Eucalyptus, Angophora and Corymbia. We also tested for phylogenetic signal in each of the phenolic groups. Many eucalypts contained high concentrations of polyphenols, particularly ellagitannins, which have been relatively poorly studied, but may possess strong oxidative activity. Because the biosynthetic pathways of many phenolic compounds share either precursors or enzymes, we found negative correlations between the concentrations of several of the constituents that we measured, including proanthocyanidins (PAs) and hydrolysable tannins (HTs), HTs and flavonol derivatives, and HTs and quinic acid derivatives. We observed moderate phylogenetic signal in all polyphenol constituents, apart from the concentration of the prodelphinidin subunit of PAs and the mean degree of polymerisation of PAs. These two traits, which have previously been shown to be important in determining plants' protein precipitation capacity, may have evolved under selection, perhaps in response to climate or herbivore pressure. Hence, the signature of evolutionary history appears to have been erased for these traits. This study is an important step in moving away from analysing “totals” to a better understanding of how phylogenetic effects influence phenolic composition, and how this in turn influences ecological processes.

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Datum: 24.11.2017


Alkaloids and flavonoid glycosides from the aerial parts of Leonurus japonicus and their opposite effects on uterine smooth muscle

Publication date: January 2018
Source:Phytochemistry, Volume 145

Author(s): Juan Liu, Cheng Peng, Qin-Mei Zhou, Li Guo, Zhao-Hua Liu, Liang Xiong

The crude extract and some Chinese patented medicines of Leonurus japonicus Houtt. have been proven to affect the uterine smooth muscle. L. japonicus injection is widely used in obstetric departments in China for treating postpartum hemorrhage caused by uterine inertia. Bioassay-guided isolation of the 95% EtOH extract of L. japonicus yielded four cyclopeptides, nine alkaloids, and three flavonoid glycosides, including two previously undescribed cyclopeptides, namely, cycloleonuripeptide G and cycloleonuripeptide H. The structures of the cyclopeptides were elucidated to be cyclo-(L-Phe-L-Phe-Gly-L-Pro-Gly-L-Pro) and cyclo-(L-Phe-L-Ala-L-Pro-L-Ile-L-His-Gly-L-Ala-L-Pro), respectively, via spectroscopic and chemical methods. Cyclopeptides (cycloleonuripeptides C and D) and alkaloids (imperialine-3β-D-glucoside and leonurine) promoted contraction of uterine smooth muscle strips isolated from normal rats. However, it was observed that flavonoid glycosides (spinosin, linarin, and apigenin-7-O-β-D-glucopyranoside) significantly inhibited contraction of the uterine smooth muscle strips.

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Datum: 24.11.2017


Dammarane-type saponins from the leaves of Panax notoginseng and their neuroprotective effects on damaged SH-SY5Y cells

Publication date: January 2018
Source:Phytochemistry, Volume 145

Author(s): Xin-Yi Liu, Shan Wang, Chuang-Jun Li, Jie Ma, Fang-You Chen, Ying Peng, Xiao-Liang Wang, Dong-Ming Zhang

Seven dammarane-type saponins previously undescribed (notoginsenosides Fh1-Fh7) were isolated from the aqueous extract leaves of Panax notoginseng (Burk.) F.H.Chen (Araliaceae), together with eleven known saponins. Their structures of were elucidated by spectroscopic analysis (NMR, UV, IR, ect.), HR-ESI-MS techniques and chemical methods. Screening results indicated that compounds 4, 5, 12, 13 showed moderate neuroprotective effects on H2O2-induced cellular damage in human neuroblastoma SH-SY5Y cells (10 μM).

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Datum: 24.11.2017


Rubipodanones A-D, naphthohydroquinone dimers from the roots and rhizomes of Rubia podantha

Publication date: January 2018
Source:Phytochemistry, Volume 145

Author(s): Zhe Wang, Si-Meng Zhao, Yan-Yun Hu, Li Feng, Li-Mei Zhao, Ying-Tong Di, Ning-Hua Tan

Four previously undescribed naphthohydroquinone dimers named rubipodanones A-D, together with 19 known quinones containing three known napthohydroquinone dimers named rubioncolin C, methyl 5-hydroxy-dinaphtho[1,2-2′,3′]furan-7,12-dione-6-carboxylate and rubialatin B, were isolated from the roots and rhizomes of Rubia podantha. Their structures and absolute configurations were determined mainly by NMR, X-ray diffraction, and computational methods. Rubipodanones C and D, the glycosides of rubipodanone A and a pair of C-3 epimer, are the first identified dimeric napthohydroquinone glycosides from the Rubia plants. All naphthohydroquinone dimers were evaluated for their cytotoxicities against ten tumor cell lines and effects on the tumor-associated NF-κB signaling pathway, and rubioncolin C showed the best cytotoxicity with IC50 value of 1.53 μM and NF-κB inhibitory activity with IC50 value of 2.97 μM. These results also demonstrated that the key roles of C-3 configuration and sugar group for biological activities of rubipodanone C.

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Datum: 24.11.2017


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: 24.11.2017


Triterpenoidal saponins from the fruits of Gleditsia caspica with proapoptotic properties

Publication date: January 2018
Source:Phytochemistry, Volume 145

Author(s): Usama Shaheen, Ehab A. Ragab, Ashraf N. Abdalla, Ammar Bader

Three previously undescribed oleanane-type triterpenoidal saponins named caspicaosides L-N were isolated from the fruits of Gleditsia caspica Desf. The aglycons of these saponins were echinocystic acid, erythrodiol and 12-oleanene-3,28,30-triol. Caspicaoside L is a bisdesmosidic saponin acylated with two monoterpenic acids. It has a disaccharide moiety made up of glucose and arabinose attached to C-3 and pentasaccharide moiety linked to C-28 made up of one glucose, 2 xyloses, one inner rhamnose and one terminal rhamnose which was acylated with two identical monoterpenic acids. Caspicaoside M is a monodesmosidic saponin with a trisaccharide moiety at C-3 made up of glucose, xylose and arabinose, while caspicaoside N has a disaccharide moiety at C-3 made up of glucose and arabinose. Their structures were determined by extensive 1D and 2D (DQF-COSY, HSQC, TOCSY, 1H-13C-HSQC-TOCSY, HMBC, ROESY, NOESY) NMR, HRESIMS analyses and chemical degradation. The cytotoxicity MTT-based assay showed that caspicaosides M, N and L, respectively, exhibited high cytotoxic activity with IC50 ≤ 10 μM (72 h) at least against one of the three used cancer cell lines, MCF 7, A2780 and HT 29; and were 2–34 folds selective against the normal fibroblasts (MRC 5). All compounds also induced apoptosis and caused G2/M arrest in MCF 7 cells (24 h); thus showing pro-apoptotic properties.

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Datum: 24.11.2017


Chemical analysis of the Alphaproteobacterium strain MOLA1416 associated with the marine lichen Lichina pygmaea

Publication date: January 2018
Source:Phytochemistry, Volume 145

Author(s): Delphine Parrot, Laurent Intertaglia, Philippe Jehan, Martin Grube, Marcelino T. Suzuki, Sophie Tomasi

Alphaproteobacterium strain MOLA1416, related to Mycoplana ramosa DSM 7292 and Chelativorans intermedius CC-MHSW-5 (93.6% 16S rRNA sequence identity) was isolated from the marine lichen, Lichina pygmaea and its chemical composition was characterized by a metabolomic network analysis using LC-MS/MS data. Twenty-five putative different compounds were revealed using a dereplication workflow based on MS/MS signatures available through GNPS (https://gnps.ucsd.edu/). In total, ten chemical families were highlighted including isocoumarins, macrolactones, erythrinan alkaloids, prodiginines, isoflavones, cyclohexane-diones, sterols, diketopiperazines, amino-acids and most likely glucocorticoids. Among those compounds, two known metabolites (13 and 26) were isolated and structurally identified and metabolite 26 showed a high cytotoxic activity against B16 melanoma cell lines with an IC50 0.6 ± 0.07 μg/mL.

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Datum: 24.11.2017


Post photosynthetic carbon partitioning to sugar alcohols and consequences for plant growth

Publication date: December 2017
Source:Phytochemistry, Volume 144

Author(s): Kathryn Dumschott, Andreas Richter, Wayne Loescher, Andrew Merchant

The occurrence of sugar alcohols is ubiquitous among plants. Physiochemical properties of sugar alcohols suggest numerous primary and secondary functions in plant tissues and are often well documented. In addition to functions arising from physiochemical properties, the synthesis of sugar alcohols may have significant influence over photosynthetic, respiratory, and developmental processes owing to their function as a large sink for photosynthates. Sink strength is demonstrated by the high concentrations of sugar alcohols found in plant tissues and their ability to be readily transported. The plant scale distribution and physiochemical function of these compounds renders them strong candidates for functioning as stress metabolites. Despite this, several aspects of sugar alcohol biosynthesis and function are poorly characterised namely: 1) the quantitative characterisation of carbon flux into the sugar alcohol pool; 2) the molecular control governing sugar alcohol biosynthesis on a quantitative basis; 3) the role of sugar alcohols in plant growth and ecology; and 4) consequences of sugar alcohol synthesis for yield production and yield quality. We highlight the need to adopt new approaches to investigating sugar alcohol biosynthesis using modern technologies in gene expression, metabolic flux analysis and agronomy. Combined, these approaches will elucidate the impact of sugar alcohol biosynthesis on growth, stress tolerance, yield and yield quality.

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Datum: 24.11.2017


Identification of iridoid synthases from Nepeta species: Iridoid cyclization does not determine nepetalactone stereochemistry

Publication date: January 2018
Source:Phytochemistry, Volume 145

Author(s): Nathaniel H. Sherden, Benjamin Lichman, Lorenzo Caputi, Dongyan Zhao, Mohamed O. Kamileen, C. Robin Buell, Sarah E. O'Connor

Nepetalactones are iridoid monoterpenes with a broad range of biological activities produced by plants in the Nepeta genus. However, none of the genes for nepetalactone biosynthesis have been discovered. Here we report the transcriptomes of two Nepeta species, each with distinctive profiles of nepetalactone stereoisomers. As a starting point for investigation of nepetalactone biosynthesis in Nepeta, these transcriptomes were used to identify candidate genes for iridoid synthase homologs, an enzyme that has been shown to form the core iridoid skeleton in several iridoid producing plant species. Iridoid synthase homologs identified from the transcriptomes were cloned, heterologously expressed, and then assayed with the 8-oxogeranial substrate. These experiments revealed that catalytically active iridoid synthase enzymes are present in Nepeta, though there are unusual mutations in key active site residues. Nevertheless, these enzymes exhibit similar catalytic activity and product profile compared to previously reported iridoid synthases from other plants. Notably, four nepetalactone stereoisomers with differing stereochemistry at the 4α and 7α positions – which are generated during the iridoid synthase reaction – are observed at different ratios in various Nepeta species. This work strongly suggests that the variable stereochemistry at these 4α and 7α positions of nepetalactone diastereomers is established further downstream in the iridoid pathway in Nepeta. Overall, this work provides a gateway into the biosynthesis of nepetalactones in Nepeta.

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Datum: 24.11.2017


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: 24.11.2017


Guaianolide sesquiterpene lactones and aporphine alkaloids from the stem bark of Guatteria friesiana

Publication date: January 2018
Source:Phytochemistry, Volume 145

Author(s): Emmanoel V. Costa, Liviane N. Soares, Maria L.B. Pinheiro, Beatriz H.L.N.S. Maia, Francisco A. Marques, Andersson Barison, Jackson R.G.S. Almeida, Iran L. Sousa, Renan S. Galaverna, Gabriel Heerdt, Nelson H. Morgon, Leonard D.R. Acho, Emerson S. Lima, Felipe M.A. da Silva, Hector H.F. Koolen

Three guaianolide sesquiterpenes, denoted guatterfriesols A-C, and four aporphine alkaloid derivatives were isolated from the stem bark of the Amazonian plant Guatteria friesiana. Thus far, sesquiterpene lactones have not been described in Annonaceae. Structures of the previously undescribed compounds were established by using 1D and 2D NMR spectroscopy in combination with MS. The absolute stereochemistry was assigned via NOE NMR experiments, ECD spectroscopy, and theoretical calculations using the TDDFT approach. Among the isolated compounds, the alkaloid guatterfriesidine showed anti-glycation activity by inhibiting the formation of advanced glycation end-products (AGEs) through the prevention of oxidation in both BSA/methylglyoxal and BSA/fructose systems.

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Datum: 24.11.2017


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: 24.11.2017


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: 24.11.2017


Metabolic solutions to the biosynthesis of some diaminomonocarboxylic acids in nature: Formation in cyanobacteria of the neurotoxins 3-N-methyl-2,3-diaminopropanoic acid (BMAA) and 2,4-diaminobutanoic acid (2,4-DAB)

Publication date: December 2017
Source:Phytochemistry, Volume 144

Author(s): Peter B. Nunn, Geoffrey A. Codd

The non-encoded diaminomonocarboxylic acids, 3-N-methyl-2,3-diaminopropanoic acid (syn: α-amino-β-methylaminopropionic acid, MeDAP; β-N-methylaminoalanine, BMAA) and 2,4-diaminobutanoic acid (2,4-DAB), are distributed widely in cyanobacterial species in free and bound forms. Both amino acids are neurotoxic in whole animal and cell-based bioassays. The biosynthetic pathway to 2,4-DAB is well documented in bacteria and in one higher plant species, but has not been confirmed in cyanobacteria. The biosynthetic pathway to BMAA is unknown. This review considers possible metabolic routes, by analogy with reactions used in other species, by which these amino acids might be biosynthesised by cyanobacteria, which are a widespread potential environmental source of these neurotoxins. Where possible, the gene expression that might be implicated in these biosyntheses is discussed.

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Datum: 24.11.2017


Deciphering the chemical origin of the semen-like floral scents in three angiosperm plants

Publication date: January 2018
Source:Phytochemistry, Volume 145

Author(s): Xiaoping Zhang, Konstantin Chingin, Dacai Zhong, Liping Luo, Vladimir Frankevich, Huanwen Chen

The chemical origin and biological role of distinct semen-like odor occasionally found in some flowers are very curious but remain scarcely studied. Here, we used direct ambient corona discharge ionization mass spectrometry (MS) to study the volatile chemical composition behind the semen-like odor emitted by the fresh flowers of Photinia serrulata, Castanopsis sclerophylla and Stemona japonica without any chemical pretreatment. Chemical identification was performed using high-resolution MS analysis in combination with tandem MS analysis and whenever possible was confirmed by the analysis of standard reference compounds. A total of 19 compounds, mostly belonging to nitrogenous volatiles, were identified in P. serrulata, C. sclerophylla, and S. japonica flowers, 1-pyrroline, 1-piperideine, 2-pyrrolidone, and phenethylamine being common in all the three studied species. Several lines of evidence indicate that the major component responsible for the semen-like odor is most likely 1-pyrroline. 1-Pyrroline is most probably formed via the oxidative deamination of putrescine, as indicated by the observation of signal from 4-amino-butanal intermediate. Flower visitation observations suggest that the released volatiles serve to attract dipterans, including Syrphidae, Calliphoridae, and Muscidae. On the analytical side, the comparison of our results to earlier studies also indicate that compared to the traditional GC-MS approach the direct corona discharge ionization mass spectrometry provides more sensitive detection of VOCs with high proton affinity, in particular volatile amines, and therefore can be used to complement traditional GC-MS approach for the highest chemical coverage of VOC analysis.

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Datum: 24.11.2017


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: 24.11.2017


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: 24.11.2017


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: 24.11.2017


Diterpenes from the stem bark of Euphorbia neriifolia and their in vitro anti-HIV activity

Publication date: January 2018
Source:Phytochemistry, Volume 145

Author(s): Shi-Li Yan, Yan-Hong Li, Xuan-Qin Chen, Dan Liu, Chin-Ho Chen, Rong-Tao Li

Six previously undescribed diterpenoids, named euphorantins S–T and euphorneroids A–D, including ingol and ent-atisane types, along with eleven known diterpenoids, were isolated from Euphorbia neriifolia. Their structures were elucidated on the basis of extensive NMR analysis and high resolution mass spectrometry. Euphorneroid D and ent-3-oxoatisan-16α,17-acetonide exhibited moderate anti-HIV-1 activities, with EC50 values of 34 μM (SI = 2.3) and 24 μM (SI = 1.9), respectively.

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Datum: 24.11.2017


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: 24.11.2017


Odor-active constituents of Cedrus atlantica wood essential oil

Publication date: December 2017
Source:Phytochemistry, Volume 144

Author(s): Ayaka Uehara, Basma Tommis, Emilie Belhassen, Badr Satrani, Mohamed Ghanmi, Nicolas Baldovini

The main odorant constituents of Cedrus atlantica essential oil were characterized by GC-Olfactometry (GC-O), using the Aroma Extract Dilution Analysis (AEDA) methodology with 12 panelists. The two most potent odor-active constituents were vestitenone and 4-acetyl-1-methylcyclohexene. The identification of the odorants was realized by a detailed fractionation of the essential oil by liquid-liquid basic extraction, distillation and column chromatography, followed by the GC-MS and GC-O analyses of some fractions, and the synthesis of some non-commercial reference constituents.

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Datum: 24.11.2017


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: 24.11.2017


Mappianines A−E, structurally diverse monoterpenoid indole alkaloids from Mappianthus iodoides

Publication date: January 2018
Source:Phytochemistry, Volume 145

Author(s): Gui-Jie Zhang, Feng Hu, Huan Jiang, Lu-Mei Dai, Hai-Bing Liao, Ning Li, Heng-Shan Wang, Ying-Ming Pan, Dong Liang

Five previously undescribed monoterpenoid indole alkaloids, mappianines A−E, along with twelve known analogues, were isolated from the stems of Mappianthus iodoides Hand.-Mazz. Their structures and absolute configurations were determined by spectroscopic analysis, single-crystal X-ray diffraction, and ECD calculations. The plausible biogenetic pathway of mappianine A was proposed. All the isolated compounds were evaluated for their cytotoxic effects on MGC-803, Bel-7404, A549, NCI-H460, and HepG2 cancer cell lines. Mappianine B, tetrahydroalstonine, β-carbolin-1-one, and 1,2,3,4-tetrahydronorharman-1-one displayed moderate cytotoxicity against all cell lines tested, with IC50 values ranging from 5.19 to 42.86 μM.

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Datum: 24.11.2017


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: 24.11.2017


50 years of research on α-amino-β-methylaminopropionic acid (β-methylaminoalanine)

Publication date: December 2017
Source:Phytochemistry, Volume 144

Author(s): Peter B. Nunn

The isolation of α-amino-β-methylaminopropionic acid from seeds of Cycas circinalis (now C. micronesica Hill) resulted from a purposeful attempt to establish the cause of the profound neurological disease, amyotrophic lateral sclerosis/parkinsonism/dementia, that existed in high frequency amongst the inhabitants of the western Pacific island of Guam (Guam ALS/PD). In the 50 years since its discovery the amino acid has been a stimulus, and sometimes a subject of mockery, for generations of scientists in a remarkably diverse range of subject areas. The number of citations of the original paper has risen in the five decades from a few to 120 within the decade 2007–2016 and continues at a high rate into the next decade. The reasons for this remarkable outcome are discussed and examples from the literature are used to illustrate the wide range of scientific interest that the original paper generated.

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Datum: 24.11.2017


Determination of hydroxycinnamic acids present in Rhododendron species

Publication date: December 2017
Source:Phytochemistry, Volume 144

Author(s): Abhinandan Shrestha, Inamullah Hakeem Said, Anne Grimbs, Naika Thielen, Lucas Lansing, Hartwig Schepker, Nikolai Kuhnert

Hydroxycinnamates including free hydroxycinnamic acids and their chlorogenic acid derivatives and glycosides have been profiled in leaf extracts of 98 Rhododendron species using LC-MS techniques. In total, 69 hydroxycinnamic acid derivatives were identified in the leaves of 98 Rhododendron species. Some derivatives serve as unique phytochemical marker for a single species, whereas other compounds are limited to certain subgenera. The distribution of compounds among six different subgenera of Rhododendron was studied using PCA and PLS-DA. This contribution presents data that provide unique metabolomic insight in the distribution of a class of secondary metabolites within a large selection of species from the botanically diverse plant genus Rhododendron.

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Datum: 24.11.2017


Sanguinarine is reduced by NADH through a covalent adduct

Publication date: January 2018
Source:Phytochemistry, Volume 145

Author(s): Roman Sandor, Jiri Slanina, Adam Midlik, Kristyna Sebrlova, Lucie Novotna, Martina Carnecka, Iva Slaninova, Petr Taborsky, Eva Taborska, Ondrej Pes

Sanguinarine is a benzo[c]phenanthridine alkaloid with interesting cytotoxic properties, such as induction of oxidative DNA damage and very rapid apoptosis, which is not mediated by p53-dependent signaling. It has been previously documented that sanguinarine is reduced with NADH even in absence of any enzymes while being converted to its dihydro form. We found that the dark blue fluorescent species, observed during sanguinarine reduction with NADH and misinterpreted by Matkar et al. (Arch. Biochem. Biophys. 2008, 477, 43–52) as an anionic form of the alkaloid, is a covalent adduct formed by the interaction of NADH and sanguinarine. The covalent adduct is then converted slowly to the products, dihydrosanguinarine and NAD+, in the second step of reduction. The product of the reduction, dihydrosanguinarine, was continually re-oxidized by the atmospheric oxygen back to sanguinarine, resulting in further reacting with NADH and eventually depleting all NADH molecules. The ability of sanguinarine to diminish the pool of NADH and NADPH is further considered when explaining the sanguinarine-induced apoptosis in living cells.

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Datum: 24.11.2017


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: 24.11.2017


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: 24.11.2017


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: 24.11.2017


Seco-dammarane triterpenoids from the leaves of Cyclocarya paliurus

Publication date: January 2018
Source:Phytochemistry, Volume 145

Author(s): Yan-jiao Chen, Liang Na, Jialong Fan, Jianping Zhao, Nusrat Hussain, Yu-qing Jian, Hanwen Yuan, Bin Li, Bin Liu, M. Iqbal Choudhary, Ikhlas Khan, Wei Wang

The leaves of Cyclocarya paliurus with sweet taste are often used as herbal tea in People's Republic of China. In this study eight previously undescribed seco-dammarane type triterpenoids, cyclocariols A-H along with seven known compounds were isolated and characterized from its leaves. A possible biogenetic pathway for seco-dammarane type triterpenoids formation has been discussed. Cyclocariols A-H were evaluated for their cytotoxicities against human liver (SMMC-7721) and breast cancer (BT-549) cell lines. Cyclocariols A, B, E, and H were also tested against human colon tumor (HCT-116) cell lines, where all four exhibited good activities with IC50 values of 6.53, 4.94, 8.24, and 6.48 μM, respectively.

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Datum: 24.11.2017


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: 24.11.2017


Alkaloid constituents from Viola tianschanica

Publication date: December 2017
Source:Phytochemistry, Volume 144

Author(s): Qi-Bin Chen, Haji Akber Aisa

Eighteen previously undescribed alkaloids, tishaviolamines A−J, including eight pairs of enantiomers, together with two known benzylisoquinoline alkaloids, (−)-bicuculline and (−)-corlumine, were isolated from Viola tianschanica. Among them, tishaviolamine A−E were demonstrated to possess three types of unpresented skeletons. The structures of these alkaloids were established by comprehensive analyses of the 1D, 2D-NMR and (+)HRESIMS data. The absolute configurations of enantiomers were determined by comparing their calculated ECD spectra with the experimental ones. The menin−mixed lineage leukemia 1 protein−protein interaction inhibitory effect of the isolated compounds were also measured.

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Datum: 24.11.2017


Triterpenes derived from hydrolyzate of total Gynostemma pentaphyllum saponins with anti-hepatic fibrosis and protective activity against H2O2-induced injury

Publication date: December 2017
Source:Phytochemistry, Volume 144

Author(s): Xiaoshu Zhang, Guohui Shi, Yuanyuan Sun, Xiaojun Wu, Yuqing Zhao

Gynostemma pentaphyllum is a popular functional food, and it is also used as a traditional medicine in Asia. In this study, five previously undescribed triterpenes, gypensapogenin M, gypensapogenin N, gypensapogenin O, gypensapogenin P, and gypensapogenin Q, together with five known compounds were isolated from the hydrolyzate of total G. pentaphyllum saponins. The bioassay data showed that all the triterpenes exhibited significant protective activity against H2O2-induced myocardial cell injury and anti-hepatic fibrosis activity. Taken together, the discovery of these triterpenes from the hydrolyzate of total G. pentaphyllum saponins expands its use as a functional food for preventing myocardial injury and liver fibrosis.

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Datum: 24.11.2017


Highly oxygenated and structurally diverse diterpenoids from Euphorbia helioscopia

Publication date: January 2018
Source:Phytochemistry, Volume 145

Author(s): Wan-Ping Wang, Kun Jiang, Ping Zhang, Kai-Kai Shen, Shi-Jin Qu, Xiao-Ping Yu, Chang-Heng Tan

A phytochemical investigation on the aerial part of Euphorbia helioscopia (Euphorbiaceae) led to the isolation of 22 highly oxygenated diterpenoids with structural types of ent-abietane, ent-kaurane, lathyrane, ent-atisane and ingenane. 17 of them, named euphelionolides A – N, 16-epi-18-hydroxy-abbeokutone, as well as eupheliotriols A and B, were identified to be previously undescribed compounds by extensive analysis of spectroscopic data. The stereostructures of euphelionolides A – K were determined by single crystal X-ray diffraction combined with analysis of substituent effects and comparison of optical characteristics. Eupheliotriol B is the first example of natural occurring lathyrol with 12Z-ene, while ent-atisanes are the first reported from the title plant. Furthermore, euphelionolides F and L exhibited significant cytotoxicity against MCF-7 and PANC-1 cell lines.

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Datum: 24.11.2017


Outside Front Cover

Publication date: November 2017
Source:Phytochemistry, Volume 143










Datum: 24.11.2017






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