显示样式:     当前期刊: Phytochemistry    加入关注       排序: 导出
我的关注
我的收藏
您暂时未登录!
登录
  • Steroidal glycosides from Ornithogalum dubium Houtt
    Phytochemistry (IF 3.186) Pub Date : 2019-02-10
    Nampoina Andriamisaina, Anne-Claire Mitaine-Offer, Tomofumi Miyamoto, Chiaki Tanaka, Thomas Paululat, Frédéric Lirussi, Marie-Aleth Lacaille-Dubois
    更新日期:2019-02-11
  • Diterpenoid alkaloids from the whole plant of Aconitum tanguticum (Maxim.) Stapf
    Phytochemistry (IF 3.186) Pub Date : 2019-02-06
    Xiaorui Fan, Lihua Yang, Zihan Liu, Limei Lin, Chun Li, Shanshan Guo, Zhimin Wang, Zhuju Wang, Feng Sui
    更新日期:2019-02-08
  • Chemical components from Metapanax delavayi leaves and their anti-BHP activities in vitro
    Phytochemistry (IF 3.186) Pub Date : 2019-02-01
    Chongzhi Sun, Yang Wu, Bei Jiang, Ying Peng, Mengyue Wang, Jiaxun Li, Xiaobo Li
    更新日期:2019-02-05
  • Volatile monoterpene ‘fingerprints’ of resinous Protium tree species in the Amazon rainforest
    Phytochemistry (IF 3.186) Pub Date : 2019-02-01
    Luani R.de O. Piva, Kolby J. Jardine, Bruno O. Gimenez, Ricardo O. Perdiz, Valdiek S. Menezes, Flávia M. Durgante, Leticia O. Cobello, Niro Higuchi, Jeffrey Q. Chambers
    更新日期:2019-02-05
  • Cytochrome P450 enzymes: A driving force of plant diterpene diversity
    Phytochemistry (IF 3.186) Pub Date : 2019-02-05
    Ulschan Bathe, Alain Tissier
    更新日期:2019-02-05
  • Cytotoxic 9,19-cycloartane type triterpenoid glycosides from the roots of Actaea dahurica
    Phytochemistry (IF 3.186) Pub Date : 2019-01-29
    Xu-Yan Wang, Chuang-Jun Li, Jie Ma, Chuan Li, Fang-You Chen, Nan Wang, Cang-Jie Shen, Dong-Ming Zhang
    更新日期:2019-01-30
  • 更新日期:2019-01-28
  • Occurrence and distribution of unsubstituted B-ring flavanones in Eucalyptus foliage
    Phytochemistry (IF 3.186) Pub Date : 2019-01-23
    Karen J. Marsh, Isha Saraf, Charles H. Hocart, Kara Youngentob, Inder-Pal Singh, William J. Foley
    更新日期:2019-01-24
  • LC-MS guided isolation and dereplication of Lycopodium alkaloids from Lycopodium cernuum var. sikkimense of different geographical origins
    Phytochemistry (IF 3.186) Pub Date : 2019-01-22
    Yu Tang, Na Li, Yike Zou, Yanran Ai, Guang-Lei Ma, Ezzat E.A. Osman, Juan Xiong, Junmin Li, Ze-Xin Jin, Jin-Feng Hu
    更新日期:2019-01-23
  • The influence of the H5⋯OC4 intramolecular hydrogen-bond (IHB) on the antioxidative activity of flavonoid
    Phytochemistry (IF 3.186) Pub Date : 2019-01-19
    Yan-Zhen Zheng, Geng Deng, Rui Guo, Zhong-Min Fu, Da-Fu Chen
    更新日期:2019-01-23
  • Identification of fermented tea (Camellia sinensis) polyphenols and their inhibitory activities against amyloid-beta aggregation
    Phytochemistry (IF 3.186) Pub Date : 2019-01-17
    Taewoong Rho, Min Sik Choi, Mila Jung, Hyun Woo Kil, Yong Deog Hong, Kee Dong Yoon
    更新日期:2019-01-23
  • Characterization of enantiomeric lignanamides from Solanum nigrum L. and their neuroprotective effects against MPP+-induced SH-SY5Y cells injury
    Phytochemistry (IF 3.186) Pub Date : 2019-01-17
    Chen-Xi Li, Xiao-Yu Song, Wen-Yu Zhao, Guo-Dong Yao, Bin Lin, Xiao-Xiao Huang, Ling-Zhi Li, Shao-Jiang Song
    更新日期:2019-01-18
  • Cycloartane triterpenoids from Actaea vaginata with anti-inflammatory effects in LPS-stimulated RAW264.7 macrophages
    Phytochemistry (IF 3.186) Pub Date : 2019-01-12
    Zhu-Jun Fang, Tian Zhang, Shi-Xin Chen, Yan-Lan Wang, Chang-Xin Zhou, Jian-Xia Mo, Yong-Jiang Wu, You-Kai Xu, Li-Gen Lin, Li-She Gan
    更新日期:2019-01-13
  • A phytochemical investigation of Stemona parviflora roots reveals several compounds with nematocidal activity
    Phytochemistry (IF 3.186) Pub Date : 2019-01-08
    Sheng-Zhuo Huang, Fan-Dong Kong, Gao Chen, Xiang-Hai Cai, Li-Man Zhou, Qing-Yun Ma, Qi Wang, Wen-Li Mei, Hao-Fu Dai, You-Xing Zhao
    更新日期:2019-01-10
  • Cholinesterase inhibitory isoquinoline alkaloids from Corydalis mucronifera
    Phytochemistry (IF 3.186) Pub Date : 2019-01-09
    Jun Zhang, Chen Zhang, Fu-Chun Xu, Quesheng, Qing-Ying Zhang, Peng-Fei Tu, Hong Liang
    更新日期:2019-01-10
  • 更新日期:2019-01-10
  • The identification and functional characterization of three liverwort class I O-methyltransferases
    Phytochemistry (IF 3.186) Pub Date : 2019-01-09
    Hui Liu, Rui-Xue Xu, Xiao-Shuang Zhang, Ting-Ting Zhu, Hong-Xiang Lou, Ai-Xia Cheng
    更新日期:2019-01-10
  • Biosynthesis of methyleugenol and methylisoeugenol in Daucus carota leaves: Characterization of eugenol/isoeugenol synthase and O-Methyltransferase
    Phytochemistry (IF 3.186) Pub Date : 2019-01-09
    Mosaab Yahyaa, Anna Berim, Bhagwat Nawade, Muhammad Ibdah, Natalia Dudareva, Mwafaq Ibdah
    更新日期:2019-01-10
  • Purification and characterization of Bowman-Birk and Kunitz isoinhibitors from the seeds of Rhynchosia sublobata (Schumach.) Meikle, a wild relative of pigeonpea
    Phytochemistry (IF 3.186) Pub Date : 2019-01-09
    S. Soundappan Mohanraj, Mariyamma Gujjarlapudi, Vadthya Lokya, Nalini Mallikarjuna, Aparna Dutta-Gupta, Kollipara Padmasree
    更新日期:2019-01-10
  • In depth LC-ESIMSn-guided phytochemical analysis of Ziziphus jujuba Mill. leaves
    Phytochemistry (IF 3.186) Pub Date : 2019-01-04
    Milena Masullo, Antonietta Cerulli, Paola Montoro, Cosimo Pizza, Sonia Piacente

    Ziziphus jujuba Mill. leaves are receiving a great attention for their ability to improve sleep, exerting beneficial effects for both the heart and the central nervous system. With the aim to obtain a comprehensive analysis of the specialised metabolites occurring in the leaves of Z. jujuba, a LC-ESI/(HR)Orbitrap/MS profile in negative ion mode of the methanol extract was carried out. The LC-MS profile guided the isolation of 42 compounds, of which the structures were elucidated by 1D and 2D-NMR experiments. Based on this approach, 2 previously unreported dammarane-type saponins have been characterized along with flavonoid derivatives, dammarane-type saponins and triterpenic acids. Dammarane-type saponins were tested for their cytotoxic activity against A549 and HeLa cancer cell lines. None of the tested compounds, in a range of concentrations between 12.5 and 100 μM, caused a significant reduction of the cell number. This work provides a deep insight on the chemistry of the leaves of Z. jujuba and could be useful for further biological studies aimed at identifying phytochemicals contributing to the health benefits attributed to this herbal drug.

    更新日期:2019-01-06
  • Metabolomics as a complement to phylogenetics for assessing intraspecific boundaries in the desiccation-tolerant medicinal shrub Myrothamnus flabellifolia (Myrothamnaceae)
    Phytochemistry (IF 3.186) Pub Date : 2019-01-03
    Joanne Bentley, John P. Moore, Jill M. Farrant

    The desiccation-tolerant shrub Myrothamnus flabellifolia has colonised a unique and harsh niche that provides little protection from the elements. It has a wide distribution range in southern Africa, occurring across an environmental gradient that is exceptionally arid in the southwest and highly mesic in the northeast. It is also harvested for use in medicinal preparations, both traditionally and commercially. However, the phytochemical variability of plants from different rainfall regions has not been assessed, nor have the intraspecific relationships been evaluated by means of a rigorously tested phylogeny. The aims of the present study were thus (1) to test a phylogenetic hypothesis for intraspecific relationships in M. flabellifolia; (2) to assess, based on the global metabolomic profiles, whether accessions collected from the three different geographic locations in southern Africa across a rainfall gradient can be differentiated, and if this corroborates the phylogenetic signature; and (3) with the aid of multivariate statistical analysis, identify and evaluate the most significant discriminatory metabolites between the three sampled regions that could act as potential barcodes. The results show that the phylogenetic and metabolomic signatures were congruent, and the metabolomic data were better able to discriminate the different populations collected from the three regions. Several potential barcodes for discriminating the material from the three regions are proposed. Quercetin-rhamnoside and 3-O-methylquercetin, both significant antioxidants, were present at significantly higher quantities in the material from the driest region in the west than from the more mesic regions in the south and east, whereas quercetin-3-O-glucuronide was significantly higher in the latter. A naringenin-like compound or arbutin derivative could discriminate the southern samples from the eastern samples, whereas digalloylglucose differentiated the eastern samples from the southern samples. In summary, the findings of this study imply that the origin of the material should be considered when used in medicinal and cosmetic preparations.

    更新日期:2019-01-06
  • Dynamic translocation of stilbene synthase VpSTS29 from a Chinese wild Vitis species upon UV irradiation
    Phytochemistry (IF 3.186) Pub Date : 2019-01-03
    Fuli Ma, Wenkong Yao, Lei Wang, Yuejin Wang

    Stilbene phytoalexins derived from grapevine can be rapidly accumulated when exposed to an artificial UV-C treatment. However, the underlying mechanisms involved in this accumulation and translocation are unclear. Here, we describe an investigation of the influence of UV-C treatment on the dynamic subcellular distribution of a member of a stilbene synthase family VpSTS29 derived from Chinese wild Vitis pseudoreticulata W.T. Wang when over-expressed in V. vinifera L. cv. Thompson Seedless. Our results show that VpSTS29-GFP was accumulated at a relatively high level in roots and mature leaves of transgenic grape lines, and was predominantly distributed in the cytoplasm. When exposed to UV-C irradiation, VpSTS29 displayed UV-induced feature coupled with the accumulation of stilbene compounds. Notably, VpSTS29-GFP can be translocated from the cytoplasm into chloroplasts upon UV-irradiation. Leaves from the two VpSTS29-GFP-expressing lines displayed more serious UV damage, showing withering and marginal scorching phenotype, and decreased content of H2O2, compared to the untransformed plant. Also, overexpression of VpSTS29 altered the expression of genes related to redox regulation, stilbene biosynthesis and light stimulus. Co-expression of VpSTS29-GFP with Glycolate oxidase 1 (myc-VpGLO1) confirmed the ability of stilbenes to decrease the content of H2O2 in Arabidopsis mesophyll protoplasts. These results provide new insight into the biological functions and properties of stilbene synthase and its product in response to environmental stimulus.

    更新日期:2019-01-06
  • Inter-organ transport of secologanin allows assembly of monoterpenoid indole alkaloids in a Catharanthus roseus mutant
    Phytochemistry (IF 3.186) Pub Date : 2019-01-03
    Trevor Kidd, Michael LAE. Easson, Yang Qu, Graham Jones, Vincenzo De Luca

    The medicinal value of the monoterpenoid indole alkaloids (MIAs) such as 3′,4′-anhydrovinblastine, as well as their chemical complexity have stimulated extensive efforts to understand the biochemical and molecular pathways involved in their biosynthesis in plants such as Catharanthus roseus, Rawvolfia serpentina and others. Ethyl methane sulphonate (EMS) mutagenesis has been used successfully together with simple MIA thin layer chromatography screening to identify C. roseus mutants with altered MIA profiles. This study describes the isolation of very low iridoid and MIA containing C. roseus mutant (M2-1582) that accumulates MIAs when the plant is provided with secologanin by feeding mutant roots or by grafting the mutant scion onto wild type roots. The observed low iridoid and MIA content was correlated with lowered expression of BIS1/BIS2 transcription factors and several genes involved in secologanin biosynthesis that are expressed in internal phloem parenchyma cells of leaves. When exogenous secologanin was applied to the roots of the mutant plant, secologanin levels rose more than 13-fold, while two major MIAs catharanthine and vindoline rose more than 8- and 4- fold, respectively. Grafting the mutant on WT stocks led to 27-, 11- and 27-fold increases in secologanin, catharanthine and vindoline, respectively in leaves of the scion one week after graft initiation. Other minor MIAs (serpentine, anhydrovinblastine, vindolidine, deacetylvindoline, tabersonine and 16-methoxytabersonine) that were not detected in the mutant, became detectable in leaves of the scion. These results provide strong evidence for a secologanin transport mechanism that mobilizes this iridoid between different plant organs in C. roseus and that secologanin transport to the mutant across the graft union permits the formation of MIAs in leaves of the mutant.

    更新日期:2019-01-06
  • Water deficit and abscisic acid treatments increase the expression of a glucomannan mannosyltransferase gene (GMMT) in Aloe vera Burm. F.
    Phytochemistry (IF 3.186) Pub Date : 2018-12-31
    Pamela Salinas, Carlos Salinas, Rodrigo A. Contreras, Gustavo E. Zuñiga, Paul Dupree, Liliana Cardemil

    The main polysaccharide of the gel present in the leaves of or Aloe vera Burm.F., (Aloe barbadensis Miller) a xerophytic crassulacean acid metabolism (CAM) plant, is an acetylated glucomannan named acemannan. This polysaccharide is responsible for the succulence of the plant, helping it to retain water. In this study we determined using polysaccharide analysis by carbohydrate gel electrophoresis (PACE) that the acemannan is a glucomannan without galactose side branches. We also investigated the expression of the gene responsible for acemannan backbone synthesis, encoding a glucomannan mannosyltransferase (GMMT, EC 2.4.1.32), since there are no previous reports on GMMT expression under water stress in general and specifically in Aloe vera. It was found by in silico analyses that the GMMT gene belongs to the cellulose synthase-like A type-9 (CSLA9) subfamily. Using RT-qPCR it was found that the expression of GMMT increased significantly in Aloe vera plants subjected to water stress. This expression correlates with an increase of endogenous ABA levels, suggesting that the gene expression could be regulated by ABA. To corroborate this hypothesis, exogenous ABA was applied to non-water-stressed plants, resulting in a significant increase of GMMT expression after 48 h of ABA treatment.

    更新日期:2019-01-02
  • Acylated pelargonidin glycosides from the red-purple flowers of Iberis umbellata L. and the red flowers of Erysimum × cheiri (L.) Crantz (Brassicaceae)
    Phytochemistry (IF 3.186) Pub Date : 2018-12-31
    Fumi Tatsuzawa

    Five previously undescribed acylated pelargonidin 3-sophoroside-5-glucosides (pigments 2–6) were isolated from the red-purple flowers of Iberis umbellata L. ‘Candycane Rose’ and ‘Candycane Red’, in addition to a known one (pigment 1). The structures of five undescribed acylated anthocyanins were determined by chemical and spectroscopic methods to be pelargonidin 3-O-[2-O-(2-O-(“acyl-A”)-β-glucopyranosyl)-6-O-(“acyl-B”)-β-glucopyranoside]-5-O-[6-O-(malonyl)-β-glucopyranoside], in which the “acyl-A” group was either trans-sinapic (2), trans-ferulic (3), trans-sinapic (4), trans-ferulic (5), or trans-ferulic acid (6), and “acyl-B” was either glucosyl-trans-p-coumaric acid (2), glucosyl-trans-p-coumaric acid (3), trans-feruloyl-glucosyl-trans-p-coumaric acid (4), trans-feruloyl-glucosyl-trans-p-coumaric acid (5), or glucosyl-trans-feruloyl-glucosyl-trans-p-coumaric acid (6). Moreover, three previously undescribed acylated pelargonidin 3-sambubioside-5-glucosides (pigments 7, 8, and 10) and one undescribed acylated pelargonidin 3-(3X-glucosylsambubioside)-5-glucoside (pigment 9) were isolated from the red flowers of Erysimum × cheiri (L.) Crantz ‘Aurora’ as major anthocyanins. The structures of the three undescribed acylated pelargonidin 3-sambubioside-5-glucosides were determined to be pelargonidin 3-O-[2-O-(2-O-(“acyl-C”)-β-xylopyranosyl)-6-O-(“acyl-D”)-β-glucopyranoside]-5-O-(β-glucopyranoside), in which the “acyl-C” group was either non (7), non (8), or trans-p-coumaric acid (10) and “acyl-D” was either trans-p-coumaric (7), trans-ferulic (8), or trans-p-coumaric acid (10). Moreover, a previously undescribed acylated pelargonidin 3-(3X-glucosylsambubioside)-5-glucoside was identified to be pelargonidin 3-O-[2-O-(2-O-(trans-p-coumaroyl)-3-O-(β-glucopyranosyl)-β-xylopyranosyl)-6-O-(trans-p-coumaroyl)-β-glucopyranoside]-5-O-(β-glucopyranoside) (9). In addition, the distribution of anthocyanidins structural elements in 24 Brassicaceous species is compared.

    更新日期:2019-01-02
  • Stress-induced modification of indole alkaloids:Phytomodificines as a new category of specialized metabolites
    Phytochemistry (IF 3.186) Pub Date : 2018-12-31
    Sara Abouzeid, Ulrike Beutling, Dirk Selmar

    This study focuses on the elucidation of the stress-induced reverse changes of major indole alkaloids in Vinca minor, primarily on the postulated conversion of vincamine and vincadifformine to yield 9-methoxyvincamine, minovincine, and minovincinine, respectively. By applying the P450 enzyme inhibitors, naproxen and resveratrol, it was shown that the oxidative reaction involved in the postulated conversion of vincamine and vincadifformine is catalyzed by cytochrome P450 enzymes. In combination with the identification of 9-hydroxyvincamine as a postulated intermediate, this result confirms that the observed stress-induced reverse changes in the alkaloid pattern are caused by modifications of the alkaloids which regularly accumulate in the healthy Vinca minor plants. Up to now, just two main types of defense compounds are distinguished: phytoalexins, which are synthesized de novo from primary metabolites and phytoanticipins, which are constitutively present in plants - either intrinsically active or are activated after cell death by hydrolysis or oxidation of the precursors. In contrast, the results presented in this paper demonstrate that indole alkaloids, representing typical phytoanticipins, are just slightly modified in response to a stress-related elicitation. Accordingly, these modified alkaloids neither represent classical phytoalexins (being synthesized de novo), nor can they be classified as phytoanticipins, since modification does not occur postmortem. Consequently, we propose a new category for these modified alkaloids that we call phytomodificines.

    更新日期:2019-01-02
  • Polycyclic polyprenylated acylphloroglucinol and phenolic metabolites from the aerial parts of Hypericum elatoides and their neuroprotective and anti-neuroinflammatory activities
    Phytochemistry (IF 3.186) Pub Date : 2018-12-26
    Xi-Tao Yan, Zhen An, Yucui Huangfu, Yuan-Teng Zhang, Chun-Huan Li, Xin Chen, Pei-Liang Liu, Jin-Ming Gao

    A phytochemical study on the aerial parts of Hypericum elatoides led to the isolation of a previously undescribed polycyclic polyprenylated acylphloroglucinol derivative, hyperelatone A, seven previously undescribed phenolic metabolites, hyperelatones B–H, along with ten known analogues. The structures of hyperelatones A–H were elucidated by 1D and 2D NMR spectroscopy, HRESIMS experiment, single-crystal X-ray diffraction and comparison of experimental and calculated ECD spectra, as well as chemical derivatization. All compounds were evaluated for their neuroprotective activity against hydrogen peroxide (H2O2)-induced cell injury in rat pheochromocytoma PC-12 cells and inhibitory effects on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in BV-2 microglial cells. Hyperelatones B–D and H, cinchonain Ib, and tenuiside A showed noticeable neuroprotection at concentrations of 1.0–100.0 μM. Hyperelatones D, G, and H, (−)-epicatechin, tenuiside A, and (Z)-3-hexenyl-β-D-glucopyranoside exhibited significant anti-neuroinflammatory activity with IC50 values ranging from 0.75 ± 0.02 to 5.83 ± 0.23 μM.

    更新日期:2019-01-01
  • Temporal resistance of potato tubers: Antibacterial assays and metabolite profiling of wound-healing tissue extracts from contrasting cultivars
    Phytochemistry (IF 3.186) Pub Date : 2018-12-28
    Keyvan Dastmalchi, Mathiu Perez Rodriguez, Janni Lin, Barney Yoo, Ruth E. Stark

    Solanum tuberosum, commonly known as the potato, is a worldwide food staple. During harvest, storage, and distribution the crop is at risk of mechanical damage. Wounding of the tuber skin can also become a point of entry for bacterial and fungal pathogens, resulting in substantial agricultural losses. Building on the proposal that potato tubers produce metabolites to defend against microbial infection during early stages of wound healing before protective suberized periderm tissues have developed, we assessed extracts of wound tissues from four potato cultivars with differing skin morphologies (Norkotah Russet, Atlantic, Chipeta, and Yukon Gold). These assays were conducted at 0, 1, 2, 3 and 7 days post wounding against the plant pathogen Erwinia carotovora and a non-pathogenic Escherichia coli strain that served as a control. For each of the potato cultivars, only polar wound tissue extracts demonstrated antibacterial activity. The polar extracts from earlier wound-healing time points (days 0, 1 and 2) displayed notably higher antibacterial activity against both strains than the later wound-healing stages (days 3 and 7). These results support a burst of antibacterial activity at early time points. Parallel metabolite profiling of the extracts revealed differences in chemical composition at different wound-healing time points and allowed for identification of potential marker compounds according to healing stage for each of the cultivars. It was possible to monitor the transformations in the metabolite profiles that could account for the phenomenon of temporal resistance by looking at the relative quantities of various metabolite classes as a function of time.

    更新日期:2019-01-01
  • Hyperbeanols F-Q, diverse monoterpenoid polyprenylated acylphloroglucinols from the flowers of Hypericum beanii
    Phytochemistry (IF 3.186) Pub Date : 2018-12-20
    Yi-Ran Li, Wen-Jun Xu, Shan-Shan Wei, Wei-Jia Lu, Jun Luo, Ling-Yi Kong

    Hyperbeanols F-Q, which are twelve undescribed monoterpenoid polyprenylated acylphloroglucinols, and four known analogues were isolated from the dried flowers of Hypericum beanii. Their structures were elucidated by detailed HRESIMS and 1D and 2D NMR data analyses. The absolute configurations of hyperbeanols FH were established by the circular dichroism (CD) exciton chirality method. The plausible biosynthetic pathway speculation of hyperbeanols F-Q indicated that diverse reactions, including prenylation, 1,6-ene reaction, rearrangement, epoxidation and dehydration, contributed to their diverse skeletons. Hyperbeanols FI, O and hypercalin B exhibited moderate nitric oxide (NO) inhibitory activities in LPS-induced RAW 264.7 macrophages, with IC50 values in the range of 17.11–28.74 μM.

    更新日期:2018-12-21
  • Peptide from thaumatin plant protein exhibits selective anticandidal activity by inducing apoptosis via membrane receptor
    Phytochemistry (IF 3.186) Pub Date : 2018-12-19
    Francisco E.S. Lopes, Helen P.S. da Costa, Pedro F.N. Souza, João P.B. Oliveira, Márcio V. Ramos, José E.C. Freire, Thiago L. Jucá, Cleverson D.T. Freitas

    Osmotin- and thaumatin-like proteins (OLPs and TLPs) have been associated with plant defense responses to different biotic stresses. In the present work, several in silico sequences from OLPs and TLPs were investigated by means of bioinformatics tools aiming to prospect for antimicrobial peptides. The peptide sequences chosen were further synthesized and characterized, and their activities and action mechanisms were assayed against some phytopathogenic fungi, bacteria and yeasts of clinical importance. From this survey approach, four peptide sequences (GDCKATSC, CPRALKVPGGCN, IVGQCPAKLKA, and CAADIVGQCPAKLK) were selected considering some chemical parameters commonly attributed to antimicrobial peptides. Antimicrobial assays showed that these peptides were unable to inhibit mycelial growth of phytopathogenic fungi and they did not affect bacterial cell growth. Nevertheless, significant inhibitory activity was found for CPRALKVPGGCN and CAADIVGQCPAKLK against Candida albicans and Saccharomyces cerevisiae. Fluorescence and scanning electron microscopy assays suggested that CAADIVGQCPAKLK did not damage the overall cell structure, or its activity was negligible on yeast membrane and cell wall integrity. However, it induced the production of reactive oxygen species (ROS) and apoptosis. Molecular docking analysis showed that CAADIVGQCPAKLK had strong affinity to interact with specific plasma membrane receptors of C. albicans and S. cerevisiae, which have been described as promoting the induction of apoptosis. The results indicate that CAADIVGQCPAKLK can be a valuable target for the development of a desired antimicrobial agent against the pathogen C. albicans.

    更新日期:2018-12-20
  • Enantiomeric β-carboline dimers from Picrasma quassioides and their anti-hepatoma potential
    Phytochemistry (IF 3.186) Pub Date : 2018-12-19
    Wen-Yu Zhao, Wei-Yu Zhou, Jing-Jie Chen, Guo-Dong Yao, Bin Lin, Xiao-Bo Wang, Xiao-Xiao Huang, Shao-Jiang Song

    Four pairs of enantiomeric β-carboline alkaloids, (+/−)-kumudine A-D, along with their biosynthesis-related compound kumudine E, were obtained from the stems of Picrasma quassioides. Their structures, including the absolute configurations, were determined via extensive spectroscopic data combined with electronic circular dichroism (ECD) spectroscopic analyses and quantum mechanical ECD calculations. (+/−)-Kumudine A possessed a scaffold of β-carboline-phenylpropanoid adduct, which were the first examples of this type of β-carboline alkaloid from nature. The cytotoxicity assay against hepatocellular carcinoma Hep3B and HepG2 cells was evaluated by SRB assay, which showed that (−)-Kumudine B had stronger effect than its enantiomer (+)-Kumudine B in Hep3B cells. Moreover, further flow cytometry analysis also supported the enantioselectivity between (+)-Kumudine B and (−)-Kumudine B, suggesting that the compounds caused death of hepatoma cells through apoptosis induction.

    更新日期:2018-12-20
  • Organ-specific distribution and non-enzymatic conversions indicate a metabolic network of phenylphenalenones in Xiphidium caeruleum
    Phytochemistry (IF 3.186) Pub Date : 2018-12-17
    Yu Chen, Christian Paetz, Bernd Schneider

    We investigated the organ-specific phytochemistry of the inflorescences, leaves at different stages of senescence, and roots of Xiphidium caeruleum (Haemodoraceae) and elucidated the structure of six undescribed compounds. Among these, a phenylcarbamoylnaphthoquinone (PCNQ), representing the first member of a class of undescribed phenylphenalenone-derived nitrogenous compounds, was identified and its spontaneous formation elaborated. Starting from phenylbenzoisochromenone glucosides, the reaction cascade proceeds through oxidative decarboxylation and several oxidation steps to an anhydride, which is further converted to a carboxy-phenylnaphthoquinone. In the presence of amino acids, this carboxy-phenylnaphthoquinone readily reacts to PCNQs. Hence, the carboxy-phenylnaphthoquinone was hypothesized to be involved in plant defense because of its reactivity towards amino acids. It was also hypothesized that reduced levels of the corresponding glucosidic phenylbenzoisochromenone precursors in older leaves may foster pathogen-driven senescence.

    更新日期:2018-12-19
  • UPLC and ESI-MS analysis of metabolites of Rauvolfia tetraphylla L. and their spatial localization using desorption electrospray ionization (DESI) mass spectrometric imaging
    Phytochemistry (IF 3.186) Pub Date : 2018-12-17
    P. Mohana Kumara, R. Uma Shaanker, T. Pradeep

    Rauvolfia tetraphylla L. (family Apocynaceae), often referred to as the wild snakeroot plant, is an important medicinal plant and produces a number of indole alkaloids in its seeds and roots. The plant is often used as a substitute for Ravuolfia serpentine (L.) Benth. ex Kurz known commonly as the Indian snakeroot plant or sarphagandha in the preparation of Ayurvedic formulations for a range of diseases including hypertension. In this study, we examine the spatial localization of the various indole alkaloids in developing fruits and plants of R. tetraphylla using desorption electrospray ionization mass spectrometry imaging (DESI-MSI). A semi-quantitative analysis of the various indole alkaloids was performed using UPLC-ESI/MS. DESI-MS images showed that the distribution of ajmalcine, yohimbine, demethyl serpentine and mitoridine are largely localized in the fruit coat while that for ajmaline is restricted to mesocarp of the fruit. At a whole plant level, the ESI-MS intensities of many of the ions were highest in the roots and lesser in the shoot region. Within the root tissue, except sarpagine and ajmalcine, all other indole alkaloids occurred in the epidermal and cortex tissues. In leaves, only serpentine, ajmalcine, reserpiline and yohimbine were present. Serpentine was restricted to the petiolar region of leaves. Principal component analysis based on the presence of the indole alkaloids, clearly separated the four tissues (stem, leaves, root and fruits) into distinct clusters. In summary, the DESI-MSI results indicated a clear tissue localization of the various indole alkaloids, in fruits, leaves and roots of R. tetraphylla. While it is not clear of how such localization is attained, we discuss the possible pathways of indole alkaloid biosynthesis and translocation during fruit and seedling development in R. tetraphylla. We also briefly discuss the functional significance of the spatial patterns in distribution of metabolites.

    更新日期:2018-12-19
  • Thiodiketopiperazines with two spirocyclic centers extracted from Botryosphaeria mamane, an endophytic fungus isolated from Bixa orellana L.
    Phytochemistry (IF 3.186) Pub Date : 2018-12-18
    Fatima Barakat, Marieke Vansteelandt, Asih Triastuti, Patricia Jargeat, Denis Jacquemin, Jérôme Graton, Kember Mejia, Billy Cabanillas, Laure Vendier, Jean-Luc Stigliani, Mohamed Haddad, Nicolas Fabre

    Three thiodiketopiperazines, botryosulfuranols A-C (1–3) were isolated from the endophytic fungus Botryosphaeria mamane. The three compounds present sulfur atoms on α- and β-positions of phenylalanine derived residues and unprecedented two spirocyclic centers at C-4 and C-2′. Their planar structures were determined by spectroscopic analysis and absolute configurations were achieved by X-ray diffraction analysis and ECD and NMR chemical shifts calculations. Botryosulfuranol A (1) was the most cytotoxic compound against four cancer cell lines (HT-29, HepG2, Caco-2, HeLa) and two healthy cell lines (IEC6, Vero) highlighting the importance of an electrophilic center for cell growth inhibition.

    更新日期:2018-12-19
  • Iridoid glucosides in the genus Sutera (Scrophulariaceae) as chemotaxonomic markers in tribe Limoselleae
    Phytochemistry (IF 3.186) Pub Date : 2018-12-18
    Chryssoula Gousiadou, Tetsuo Kokubun, Dirk C. Albach, Charlotte H. Gotfredsen, Søren Rosendal Jensen

    From two species of Sutera (S. foetida and S. cordata) (Scrophulariaceae tribe Limoselleae) were isolated three known secoiridoid glucosides (12–14) as well as four iridoid congeners (8–11), all biosynthetically derived from iridodial glucoside (and/or deoxyloganic acid). In addition, two previously unknown compounds were found, namely a terpenoid glucoside lactone (suterolide, 21) and the phenylethanoid glycoside 2′′′′-O-acetyl-angoroside A (19) as well as verbascoside, echinacoside and tubuloside A(15–17, respectively). Two other species, Jamesbrittenia dissecta and Lyperia antirrhinoides, previously considered to belong to the same genus (Sutera) were shown to be members of two different genera, respectively. Significantly, these two species contained iridoids derived from 8-epi-iridodial (and 8-epideoxyloganic acid), namely aucubin (2), melittoside (3) and acetylharpagide (4). In addition we investigated Melanospermum transvaalense, Lyperia tristis and Microdon dubius likewise from Limoselleae and all of these contained iridoid glucosides from the 8-epi-pathway. Thus, secoiridoid distribution confirms the DNA-based circumscription of Sutera and its sister-group relationship with Manulea. In addition, the results show that the clade including these two genera has a biosynthetic pathway to iridoids fundamentally different from the rest of the tribe and from the whole family Scrophulariaceae.

    更新日期:2018-12-19
  • Mass spectrometry imaging of low molecular weight metabolites in strawberry fruit (Fragaria x ananassa Duch.) cv. Primoris with 109Ag nanoparticle enhanced target
    Phytochemistry (IF 3.186) Pub Date : 2018-12-11
    Joanna Nizioł, Maria Misiorek, Tomasz Ruman

    Strawberry (Fragaria x ananassa Duch., Rosaceae) is the subject of many research studies due to its numerous features such as unique taste, aroma and health qualities. The distribution of low molecular weight metabolites belonging to aldehydes, ketones, alcohols, esters, organic acids, phenolics, amino acids and sugars classes within strawberry fruit cross-section was studied using mass spectrometry imaging (MSI) method with 109Ag nanoparticle enhanced target (109AgNPET). Correlation of distribution of over thirty compounds found in cross-section of strawberry with their biological function is also included.

    更新日期:2018-12-12
  • Volatile, stored and phloem exudate-located compounds represent different appearance levels affecting aphid niche choice
    Phytochemistry (IF 3.186) Pub Date : 2018-12-08
    Ruth Jakobs, Caroline Müller

    Intraspecific and intra-individual differences in emitted volatile compounds and in surface and phloem sap-related metabolites do not only affect host plant choice of monophagous aphids but may also guide them to the plant part that provides their ideal niche by maximising their fitness. However, little is known about the variation at these different plant appearance levels. We investigated the preferences of the monophagous aphid species Macrosiphoniella tancetaria and Uroleucon tanaceti for different plant parts (inflorescence stems, young and old leaves) of Tanacetum vulgare plants from two chemotypes, testing their reactions towards volatile, surface and phloem sap-related cues. Furthermore, we studied the variation in leaf glandular trichome density as well as in the composition of volatile, stored and phloem exudate-located specialised (secondary) plant compounds from the different plant parts of these chemotypes. Aphid species showed differences in their preferences. Aphids of M. tanacetaria had to assess the entire plant to choose the stem, whereas U. tanaceti only needed volatile cues to locate the old leaves, which are the plant parts representing their respective niches. Volatiles and stored metabolites varied in their composition and concentration between chemotypes. Stored metabolites additionally differed among plant parts, which was reflected in distinct trichome densities. The composition of phloem exudate-located specialised compounds mostly varied among plant parts. These pronounced differences in plant chemistry on multiple levels provide distinct perception levels for aphids probably driving their niche choice. This study demonstrates the importance to consider these multiple levels to elucidate plant-herbivore interactions with high resolution.

    更新日期:2018-12-10
  • Cycloartane-type triterpenoid derivatives and a flavonoid glycoside from the burs of Castanea crenata
    Phytochemistry (IF 3.186) Pub Date : 2018-12-06
    Nanyoung Kim, SeonJu Park, Nguyen Xuan Nhiem, Jae-Hyoung Song, Hyun-Jeong Ko, Seung Hyun Kim

    Five undescribed cycloartane-type triterpenoids, which were isolated for the first time from the genus, and a flavonoid glycoside together with 11 known compounds were isolated from the burs of Castanea crenata. The structures were elucidated based on the spectroscopic analysis of 1D and 2D NMR and MS data. All isolated compounds were evaluated for antiviral activities against HRV1B-, CVB3-, and PR8-infected cells. Most kaempferol derivatives showed statistically significant antiviral activities against HRV1B-infected cells. Among the tested compounds, kaempferol-3-O-[2″,6″-di-O-Z-p-coumaroyl]-β-d-glucopyranoside exhibited the most consistent and effective antiviral activities against all infections.

    更新日期:2018-12-07
  • Anti-inflammatory prenylbenzaldehyde derivatives isolated from Eurotium cristatum
    Phytochemistry (IF 3.186) Pub Date : 2018-12-05
    Panpan Zhang, Chunxiu Jia, Yanlian Deng, Senhua Chen, Bin Chen, Sujun Yan, Jing Li, Lan Liu

    Two undescribed prenylbenzaldehyde derivatives, cristaldehydes A and B, and an undescribed quinone derivative, cristaquinone A, along with seven known compounds were isolated from the fungus Eurotium cristatum. The structures of undescribed compounds were determined by spectroscopic analysis including NMR, HR-ESIMS, and single-crystal X-ray diffraction. This is the first report of identification of a dibenzannulated 6,6-spiroketal derivative, cristaldehyde B, in a natural product. Cytotoxic and anti-inflammatory activities of all compounds were evaluated. Cristaldehyde A and cristaquinone A along with five known compounds showed significant anti-inflammatory activities with IC50 values in the range from 0.37 to 14.50 μM.

    更新日期:2018-12-07
  • Undescribed C-geranylflavonoids isolated from the fruit peel of Paulownia catalpifolia T. Gong ex D.Y. Hong with their protection on human umbilical vein endothelial cells injury induced by hydrogen peroxide
    Phytochemistry (IF 3.186) Pub Date : 2018-12-05
    Ying-Ai Wang, Xing Guo, Xian-Hui Jia, Jing Xue, Hong-Fang Du, Cheng-Lin Du, Wen-Zhao Tang, Xiao-Jing Wang, Yun-Xue Zhao

    Six undescribed C-geranylated flavonoids, including five C-geranylflavanones named as paucatalinones F - J, one C-geranylflavonol named as paucatalinone K, along with seven known geranylated flavanones, were isolated from the fruit peel of Paulownia catalpifolia T. Gong ex D.Y. Hong. Their structures were elucidated distinctly according to their UV, IR, MS, NMR, and CD data. Among them, two compounds were substituted with unusual modified geranyl groups, namely paucatalinone F with an oxygenated cyclogeranyl substituent and paucatalinone H with a terminal pyranoid geranyl substituent. Furthermore, the protective effects on human umbilical vein endothelial cells (HUVECs) injury induced by H2O2 were evaluated, and paucatalinone F showed the most potential activity. The bioactive results suggested that the geranyl substituent may be an important factor for restraining oxidative HUVECs damage and Paulownia C-geranylated flavonoids might have the potential for preventing cardiovascular complications.

    更新日期:2018-12-07
  • Use of multivariate NMR analysis in the content prediction of hemicellulose, cellulose and lignin in greenhouse crop residues
    Phytochemistry (IF 3.186) Pub Date : 2018-11-28
    Luis M. Aguilera-Sáez, Francisco M. Arrabal-Campos, Ángel J. Callejón-Ferre, María D. Suárez Medina, Ignacio Fernández

    We have introduced the use of multivariate NMR analysis in the development of accurate and robust prediction models, potentially arising from a correlation between soluble metabolite profiles and cell wall composition, for the determination of hemicellulose, cellulose and lignin contents in 8 species of greenhouse crop residues. The present paper demonstrates that discriminant buckets coming from a PLS-DA model in combination with linear models provide a useful and rapid tool for the determination of cell wall composition of these plant wastes. Regularized linear regression methods have also been applied to avoid overfitting, producing improved models specifically for lignin and cellulose determinations. The predictive models are also presented in a desktop application available at http://www2.ual.es/NMRMBC/solutions. To verify the rationality and reliability of the models, control experiments following generally accepted protocols have been performed and compared to our predicted values.

    更新日期:2018-11-29
  • Manipulation of oxalate metabolism in plants for improving food quality and productivity
    Phytochemistry (IF 3.186) Pub Date : 2018-11-28
    Vinay Kumar, Mohammad Irfan, Asis Datta

    Oxalic acid is a naturally occurring metabolite in plants and a common constituent of all plant-derived human diets. Oxalic acid has diverse unrelated roles in plant metabolism, including pH regulation in association with nitrogen metabolism, metal ion homeostasis and calcium storage. In plants, oxalic acid is also a pathogenesis factor and is secreted by various fungi during host infection. Unlike those of plants, fungi and bacteria, the human genome does not contain any oxalate-degrading genes, and therefore, the consumption of large amounts of plant-derived oxalate is considered detrimental to human health. In this review, we discuss recent biotechnological approaches that have been used to reduce the oxalate content of plant tissues.

    更新日期:2018-11-29
  • Diterpene synthases facilitating production of the kaurane skeleton of eriocalyxin B in the medicinal plant Isodon eriocalyx
    Phytochemistry (IF 3.186) Pub Date : 2018-11-26
    Gang Du, Hai-Yan Gong, Ke-Na Feng, Qian-Qian Chen, Yan-Long Yang, Xiao-Li Fu, Shan Lu, Ying Zeng

    The Isodon plants (Lamiaceae) have been used in traditional Chinese medicine to alleviate sufferings from inflammations and cancers. This feature has been attributed to the presence of pharmacologically active ent-kaurane diterpenoids such as eriocalyxin B and oridonin. The Isodon eriocalyx (Dunn) Kudô species native to southwest China can accumulate a particularly high content of ent-kaurane diterpenoids (∼1.5% w/w of dried leaves). We previously identified diterpene synthases IeCPS1 and IeCPS2 as ent-copalyl diphosphate synthases (ent-CPS) potentially involved in Isodon ent-kaurane diterpenoids biosynthesis. In this study, analysis of RNA-seq transcriptome of the I. eriocalyx plant revealed three other diterpene synthase genes (IeCPS3, IeKS1, and IeKSL1). Their functional characterization through coupled in vitro enzyme assays has confirmed that IeCPS3 is an ent-CPS specifically producing ent-copalyl diphosphate (ent-CPP). IeKS1 accepted ent-CPP to produce exclusively ent-kaurene and may thus be defined as an ent-kaurene synthase (ent-KS). When IeKSL1 was combined with IeCPS2 or IeCPS3, no product was detected. Based on tissue-specific expression and metabolic localization studies, the IeCPS3 and IeKS1 transcripts were significantly accumulated in leaves where the ent-kaurane diterpenoid eriocalyxin B dominates, whereas weak expression of both were observed in germinating seeds in which gibberellin biosynthetic pathway is normally active. Our findings suggest that both IeCPS3 and IeKS1 possess dual roles in general (gibberellins) and specialized diterpenoid metabolism, such as that of the Isodon ent-kaurane diterpenoids.

    更新日期:2018-11-28
  • Diterpenoids from the Chinese liverwort Frullania hamatiloba and their Nrf2 inducing activities
    Phytochemistry (IF 3.186) Pub Date : 2018-11-24
    Ya-Nan Qiao, Yong Sun, Tao Shen, Jiao-Zhen Zhang, Jin-Chuan Zhou, Yi Li, Wang Chen, Zhao-Jie Ren, Yue-Lan Li, Xue Wang, Hong-Xiang Lou

    Six previously undescribed labdane diterpenoids, frullanians A−F, along with five known diterpenoids, were isolated from the Chinese liverwort Frullania hamatiloba Stephani. Their structures were determined using NMR data, electronic circular dichroism (ECD) calculations as well as the single crystal X-ray diffraction measurement. NAD(P)H: QR (quinone reductase) assay demonstrated that frullanian D and four known compounds displayed antioxidant effect mediated via Nrf2 (Nuclear factor-erythroid 2-related factor 2) induction. Further investigation of the most bioactive frullanian D in MOVAS cells revealed that it ameliorated H2O2-induced oxidative insults without toxicity by increasing cell viability, attenuating morphological changes, and reducing intracellular ROS production. In addition, frullanian D promoted the nuclear translocation of Nrf2 and upregulated the expressions of antioxidant proteins NQO1 (NAD(P)H quinone oxidoreductase 1) and γ-GCS (γ-glutamyl cysteine synthetase). Docking analysis using MOE software further supported the activation of the Nrf2 pathway by frullanian D.

    更新日期:2018-11-26
  • Enhanced production of unusual triterpenoids from Kadsura angustifolia fermented by a symbiont endophytic fungus, Penicillium sp. SWUKD4.1850
    Phytochemistry (IF 3.186) Pub Date : 2018-11-23
    Dan Qin, Weiyun Shen, Junqi Wang, Meijun Han, Fangni Chai, Xiaoxiang Duan, Xiao Yan, Jiali Guo, Tiancong Gao, Shihao Zuo, Jinyan Dong

    Highly oxygenated schitriterpenoids are interesting for study of their structures, bioactivities and synthesis. From Kadsura angustifolia fermented by an associated symbiotic endophytic fungus, Penicillium sp. SWUKD4.1850, nine undescribed triterpenoids, kadhenrischinins A-H, and 7β-schinalactone C together with four known triterpenoids, henrischinins A and B, schinalactone C and nigranoic acid were isolated and established by the extensive 1D-, 2D-NMR, HR-ESI-MS and ECD data analysis. Except nigranoic acid, all these metabolites have been first detected in non-fermented K. angustifolia. Structurally, kadhenrischinins A-D belong to the relatively rare class of highly oxygenated schitriterpenoids that contain a unique 3-one-2-oxabicyclo [3,2,1]-octane motif, while kadhenrischinins E-H feature a cyclopentane ring in a side chain rarely found in the family Schisandraceae. These results indicated that fermentation of K. angustifolia with SWUKD4.1850 induced the production of highly oxygenated schitriterpenoids from nigranoic acid, which provided a guidance to obtain desired compounds from those plants initially thought not to produce. This is the first report on the fermentation of K. angustifolia medical plant and the first discovery of highly oxygenated schitriterpenoids by microbial technology.

    更新日期:2018-11-26
  • A syn-ent-labdadiene derivative with a rare spiro-β-lactone function from the male cones of Wollemia nobilis
    Phytochemistry (IF 3.186) Pub Date : 2018-11-24
    Alessandro Venditti, Claudio Frezza, Flaminia Vincenti, Antonia Brodella, Fabio Sciubba, Camilla Montesano, Marco Franceschin, Manuel Sergi, Sebastiano Foddai, Maria Enrica Di Cocco, Roberta Curini, Maurizio Delfini, Armandodoriano Bianco, Mauro Serafini

    An undescribed labdane-like diterpene with a rare spiro-β-lactone function was identified from the ethanol extract of the male cones of the coniferous tree Wollemia nobilis. This spirolabdadienolide (IUPAC name: syn-ent-8(17),13-labdadien-19,18-olid-15-oic acid methyl ester; trivial name: wollemolide), was isolated by means of traditional and high performance chromatography techniques and structurally elucidated through NMR and MS. In addition, six further known metabolites were evidenced in the extract. Wollemolide, which may be considered an additional chemotaxonomic marker, and 4′-O-methyl-scutellarein, a simple flavonoid, had not been isolated in our previous phytochemical study on the same plant organ. This demonstrates how the molecular pattern of a plant species is in continuous movement and changes with the passing of time according to the climate of the year.

    更新日期:2018-11-26
  • Floral scent in Iris planifolia (Iridaceae) suggests food reward
    Phytochemistry (IF 3.186) Pub Date : 2018-11-24
    Pietro Zito, Sergio Rosselli, Maurizio Bruno, Antonella Maggio, Maurizio Sajeva

    Iris species can adopt different pollination strategies to attract their pollinators, generalized shelter-mimicking, specialized deceptive sexual-mimicking or food-rewarding. As attractive stimuli, Iris flowers may use their colours, large-size, symmetry, and volatile organic compounds (VOCs). However, relatively few studies investigated Iris floral olfactory cues in the context of plant-visitor/pollinator interactions. In the present study we combined the identification of the floral volatiles of the nectariferous I. planifolia with insects visiting its flowers to gather data on its biology. Floral volatiles were collected in the natural environment by dynamic headspace and analysed by gas chromatography-mass spectrometry (GC-MS). Insect visitors/pollinators were also recorded. The volatile bouquet was aromatic-dominated with 1,4 dimethoxybenzene as major compound. Among the insects visiting its flowers, bumble and honey bees were the most abundant followed by hover flies. Overall, our results suggest that I. planifolia advertises its food reward by an aromatic dominated volatile composition.

    更新日期:2018-11-26
  • Stigmastane-type steroids with unique conjugated Δ7,9(11) diene and highly oxygenated side chains from the twigs of Vernonia amygdalina
    Phytochemistry (IF 3.186) Pub Date : 2018-11-24
    Xiangzhong Liu, Wenjing Tian, Guanghui Wang, Qiannan Xu, Mi Zhou, Shuo Gao, Daren Qiu, Xin Jiang, Cuiling Sun, Rong Ding, Ting Lin, Haifeng Chen

    Veramyosides A-J, eleven undescribed stigmastane-type steroids, including one aglycone and ten glycosides, along with three known homologues were isolated from the twigs of Vernonia amygdalina Delile (compositae). All compounds featured a stigmastane-type steroid skeleton with a unique conjugated Δ7,9(11) diene segment and highly oxygenated side chains with a γ-lactone or an α, β-unsaturated five-membered lactone ring. The structures of veramyosides A-J and their absolute configurations were unambiguously elucidated by HR-ESI-MS, extensive NMR spectroscopy, in situ dimolybdenum CD methods, modified Mosher's method, quantum chemical calculation of their ECD curves, and CD comparison methods on basis of their biogenetic pathway. In addition, all isolates were investigated for their effects on RXRα transcription, and their effects on the NF-κB signaling pathway were also evaluated.

    更新日期:2018-11-26
  • LC-MS-guided isolation of anti-inflammatory 2-(2-phenylethyl)chromone dimers from Chinese agarwood (Aquilaria sinensis)
    Phytochemistry (IF 3.186) Pub Date : 2018-11-17
    Hui-Xia Huo, Yu-Fan Gu, Zhi-Xiang Zhu, Yun-Feng Zhang, Xiao-Nan Chen, Peng-Wei Guan, She-Po Shi, Yue-Lin Song, Yun-Fang Zhao, Peng-Fei Tu, Jun Li

    Fifteen previously undescribed 2-(2-phenylethyl)chromone dimers, along with two known analogues were isolated from Chinese agarwood (Aquilaria sinensis) by a LC-MS-guided fractionation procedure. Their structures were elucidated on the basis of spectroscopic and spectrometric data (1D and 2D NMR, IR, and HRESIMS). The isolated compounds exhibited significant inhibition of nitric oxide production in lipopolysaccharide-stimulated RAW264.7 cells with IC50 values in the range 0.6–37.1 μM.

    更新日期:2018-11-20
  • Functional characterization and correlation analysis of phenylalanine ammonia-lyase (PAL) in coumarin biosynthesis from Peucedanum praeruptorum Dunn
    Phytochemistry (IF 3.186) Pub Date : 2018-11-15
    Ziwei Sui, Jun Luo, Ruolan Yao, Chuanlong Huang, Yucheng Zhao, Lingyi Kong

    Coumarins exhibit many biological activities and are the main specialised metabolites of Peucedanum praeruptorum Dunn, an important plant used in traditional Chinese medicine. In preliminary studies, we cloned several genes involved in coumarin biosynthesis in P. praeruptorum, such as 4-coumarate: CoA ligase (4CL), p-coumaroyl CoA 2′-hydroxylase (C2′H), feruloyl CoA 6′-hydroxylase (F6′H) and bergaptol O-methyltransferase (BMT). However, phenylalanine ammonia-lyase (PAL) in P. praeruptorum (PpPAL) has not yet been studied. In the present study, we cloned one novel PpPAL gene. Subsequently, the relationship between gene and compounds was studied using quantitative real-time PCR (qRT-PCR) and High Performance Liquid Chromatography (HPLC) analysis. Then, enzyme function was analyzed with L-phenylalanine (L-Phe) as substrate. These experiments showed that the coumarin content could be upregulated by methyl jasmonate (MeJA), UV irradiation and cold, which was consistent with increased expression levels of PpPAL. In addition, correlation analysis indicated that coumarins were partially related to PpPAL. And the recombinant protein could catalyze the conversion of L-Phe to trans-cinnamic acid (t-CA) with a Km of 120 ± 33 μM and a Kcat of 117 ± 32 min−1. Besides, Tyr110, Phe116, Gly117, Ser206, Leu209, Leu259, Tyr354, Arg357, Asn387 and Phe403 were essential for enzymatic activity based on three-dimensional modeling and site-directed mutagenesis experiments. Altogether these results highlight the importance of PpPAL in abiotically induced coumarin biosynthesis and provide further insights regarding the structure-function relationships of this protein.

    更新日期:2018-11-17
  • Rare dimeric guaianes from Xylopia vielana and their multidrug resistance reversal activity
    Phytochemistry (IF 3.186) Pub Date : 2018-11-15
    Ya-Long Zhang, Qi-Qi Xu, Xu-Wei Zhou, Lin Wu, Xiao-Bing Wang, Ming-Hua Yang, Jun Luo, Jian-Guang Luo, Ling-Yi Kong

    Thirteen undescribed dimeric guaianes were isolated from the leaves of Xylopia vielana Pierre. Their structures were elucidated by NMR spectroscopy and mass spectrometry, and the absolute configurations of vielanins G-Q were determined by a combination of the circular dichroism (CD) exciton chirality method, chemical conversion, and electronic CD (ECD) spectroscopy analysis. Vielaninors A and B are the first examples of trinor-guaiane-dimers. Multidrug resistance reversal activity assay of the isolates was evaluated in doxorubicin-resistant human breast cancer cells. Vielanins H, K-M, P, and Q were noncytotoxic and enhanced the cytotoxicity of doxorubicin by 2.1–41.6-fold at 10 μM.

    更新日期:2018-11-16
  • Fusaricates H-K and fusolanones A-B from a mangrove endophytic fungus Fusarium solani HDN15-410
    Phytochemistry (IF 3.186) Pub Date : 2018-11-15
    Guoliang Zhou, Liang Qiao, Xiaomin Zhang, Chunxiao Sun, Qian Che, Guojian Zhang, Tianjiao Zhu, Qianqun Gu, Dehai Li

    Seven compounds including four undescribed fusaric acid derivatives, namely fusaricates H-K, and two undescribed γ-pyrone derivatives, named fusolanones A-B, as well as a known compound fusaric acid, were isolated from a mangrove endophytic fungus Fusarium solani. Fusaricates H-K represent the first cases of fusaric acid butanediol esters and are diastereoisomers. Their structures including absolute configurations were elucidated based on NMR, MS, chemical synthesis, chiral HPLC analysis and ECD calculations. The antibacterial activity of all undescribed compounds were tested and fusolanone B showed the best activity with MIC value 6.25 μg/mL on Vibrio parahaemolyticus.

    更新日期:2018-11-16
  • Bromocatechol conjugates from a Chinese marine red alga, Symphyocladia latiuscula
    Phytochemistry (IF 3.186) Pub Date : 2018-11-15
    Xiuli Xu, Haijin Yang, Zeinab G. Khalil, Liyuan Yin, Xue Xiao, Angela A. Salim, Fuhang Song, Robert J. Capon

    This study describes an investigation into polybromocatechol conjugates isolated from a marine red alga, Symphyocladia latiuscula (Harvey) Yamada, collected from coastal waters off Qingdao, China. We report on the isolation and characterisation of eight undescribed aconitic acid conjugates, symphyocladins R-X, including a likely solvolysis artifact of symphyocladin S, and an undescribed furanoyl conjugate, symphyocladin Y. Structure elucidation was achieved by detailed spectroscopic analysis. A plausible biosynthetic pathway linking all these co-metabolites through a cascade of quinone methide additions is proposed.

    更新日期:2018-11-16
  • Transport of organic substances through the cytoplasmic membrane of cyanobacteria
    Phytochemistry (IF 3.186) Pub Date : 2018-11-15
    Ronald Stebegg, Georg Schmetterer, Annette Rompel

    Cyanobacteria are mainly known to incorporate inorganic molecules like carbon dioxide and ammonia from the environment into organic material within the cell. Nevertheless cyanobacteria do import and export organic substances through the cytoplasmic membrane and these processes are essential for all cyanobacteria. In addition understanding the mechanisms of transport of organic molecules through the cytoplasmic membrane might become very important. Genetically modified strains of cyanobacteria could serve as producers and exporters of commercially important substances. In this review we attempt to present all data of transport of organic molecules through the cytoplasmic membrane of cyanobacteria that are currently available with the transported molecules ordered according to their chemical classes.

    更新日期:2018-11-16
  • Rhodomicranosides A−I, analgesic diterpene glucosides with diverse carbon skeletons from Rhododendron micranthum
    Phytochemistry (IF 3.186) Pub Date : 2018-11-14
    Na Sun, Yue Qiu, Yan Zhu, Junjun Liu, Hanqi Zhang, Qihua Zhang, Mengke Zhang, Guijuan Zheng, Chun Zhang, Guangmin Yao

    Nine previously undescribed diterpene glucosides, rhodomicranosides A−I, comprising leucothane, 4,5-seco-ent-kaurane, and grayanane types, respectively, were isolated from the leaves of Rhododendron micranthum, along with seven known diterpenoids. Their structures were elucidated based on extensive spectroscopic analyses such as HRESIMS, 1D and 2D NMR, UV, and IR, and their absolute configurations were determined by various methods including X-ray diffraction analysis, electronic circular dichroism spectroscopy (ECD), calculated ECD, and Mo2(OAc)4-induced ECD, as well as chemical methods. This is the first time to report the crystal structures of leucothane diterpene glycosides. Rhodomicranosides A−C represent the first examples of 15α-hydroxy-leucothane diterpenoids, leucothane diterpene diglucosides, and 9β-hydroxy-leucothane diterpenoids, respectively. Rhodomicranosides D and E are the second and third examples of 4,5-seco-ent-kaurane diterpenoids, and this is the first time to report 4,5-seco-ent-kaurane-type diterpenoids from the genus of Rhododendron. Rhodomicranosides F and G are the first examples of 5α-H-grayan-1(10),9(11)-diene-6-one diterpenoids. Some isolated diterpenoids were evaluated for their analgesic activity in an acetic acid-induced writhing test, and rhodomicranosides A−E and H, pierisformoside F, iso-grayanotoxin II, and grayanotoxins I, III, and IV showed significant analgesic effects with the percentage inhibitions over 50% at the dose of 1.0 mg/kg. In particular, grayanotoxins I and III exhibited more potent analgesic activity than morphine at a dose of 0.2 mg/kg, and they showed significant analgesic activity even at a lower dose of 0.04 mg/kg with the inhibition rates of 71.5% and 69.3%, respectively. Their preliminary structure-activity relationships were discussed.

    更新日期:2018-11-15
  • An analysis of characterized plant sesquiterpene synthases
    Phytochemistry (IF 3.186) Pub Date : 2018-11-13
    Janani Durairaj, Alice Di Girolamo, Harro J. Bouwmeester, Dick de Ridder, Jules Beekwilder, Aalt DJ. van Dijk

    Plants exhibit a vast array of sesquiterpenes, C15 hydrocarbons which often function as herbivore-repellents or pollinator-attractants. These in turn are produced by a diverse range of sesquiterpene synthases. A comprehensive analysis of these enzymes in terms of product specificity has been hampered by the lack of a centralized resource of sufficient functionally annotated sequence data. To address this, we have gathered 262 plant sesquiterpene synthase sequences with experimentally characterized products. The annotated enzyme sequences allowed for an analysis of terpene synthase motifs, leading to the extension of one motif and recognition of a variant of another. In addition, putative terpene synthase sequences were obtained from various resources and compared with the annotated sesquiterpene synthases. This analysis indicated regions of terpene synthase sequence space which so far are unexplored experimentally. Finally, we present a case describing mutational studies on residues altering product specificity, for which we analyzed conservation in our database. This demonstrates an application of our database in choosing likely-functional residues for mutagenesis studies aimed at understanding or changing sesquiterpene synthase product specificity.

    更新日期:2018-11-14
  • Lotuslactone, a non-canonical strigolactone from Lotus japonicus
    Phytochemistry (IF 3.186) Pub Date : 2018-11-12
    Xiaonan Xie, Narumi Mori, Kaori Yoneyama, Takahito Nomura, Kenichi Uchida, Koichi Yoneyama, Kohki Akiyama

    Root exudates from Lotus japonicus were found to contain at least three different hyphal branching-inducing compounds for the arbuscular mycorrhizal (AM) fungus Gigaspora margarita, one of which had been previously identified as (+)-5-deoxystrigol (5DS), a canonical strigolactone (SL). One of the two remaining unknown hyphal branching inducers was purified and named lotuslactone. Its structure was determined as methyl (E)-2-(3-acetoxy-2-hydroxy-7-methyl-1-oxo-1,2,3,4,5,6-hexahydroazulen-2-yl)-3-(((R)-4-methyl-5-oxo-2,5-dihydrofuran-2-yl)oxy)acrylate, by 1D and 2D NMR spectroscopy, and HR-ESI- and EI-MS. Although lotuslactone, a non-canonical SL, contains the AB-ring and the enol ether-bridged D-ring, it lacks the C-ring and has a seven-membered cycloheptadiene in the A-ring part as in medicaol, a major SL of Medicago truncatula. Lotuslactone was much less active than 5DS, but showed comparable activity to methyl carlactonoate (MeCLA) in inducing hyphal branching of G. margarita. Other natural non-canonical SLs including avenaol, heliolactone, and zealactone (methyl zealactonoate) were also found to be moderate to weak inducers of hyphal branching in the AM fungus. Lotuslactone strongly elicited seed germination in Phelipanche ramosa and Orobanche minor, but Striga hermonthica seeds were 100-fold less sensitive to this stimulant.

    更新日期:2018-11-13
  • Uptake and modification of umbelliferone by various seedlings
    Phytochemistry (IF 3.186) Pub Date : 2018-11-12
    Tahani Hijazin, Alzahraa Radwan, Sara Abouzeid, Gerald Dräger, Dirk Selmar

    Inspired by the recently discovered phenomenon of “horizontal natural product transfer” we investigated the putative uptake of phenolic specialized metabolites. Umbelliferone was chosen for this case study, since this coumarin as well as its derivatives can easily be determined by HPLC analyses. Barley (Hordeum vulgare L.), radish (Raphanus sativus L.), pea (Pisum sativum L.), flax (Linum usitatissimum L.), and garden cress (Lepidium sativum L.) were cultivated in hydroponic media, to which the coumarin was applied. Uptake of umbelliferone was verified by corresponding HPLC analyses of extracts obtained from the aerial parts of the seedlings. In all cases, a tremendous uptake of umbelliferone was observed. In plants that genuinely contain coumarins, the umbelliferone taken up was modified: in garden cress, it was hydroxylated and glucosylated to yield esculin, while in barley seedlings, the imported umbelliferone was modified by methoxylation to yield scopoletin. Corresponding reactions are known from modifications of xenobiotics to be catalyzed by cytochrome P450 enzymes. Accordingly, in an additional approach, umbelliferone was applied together with naproxen, which is reported to reduce enzyme activity of P450 enzymes. As predicted, the conversion of umbelliferone to scopoletin in barley as well as the modification to esculin in garden cress was strongly reduced by the addition of naproxen. These data for the first time demonstrate that – in addition to alkaloids – also phenolic compounds are taken up by various acceptor plants. Apart from the leaching of rotting plants, coumarins are known to be exuded by many plants. Accordingly, these compounds are frequently present in soils and will be taken up. These coherences imply that the horizontal natural product transfer might represent a more general phenomenon in plant ecology. Moreover, this study outlines that – in analogy to the modification of xenobiotics – also natural products taken up are modified in the acceptor plants.

    更新日期:2018-11-13
  • PgUGT95B2 preferentially metabolizes flavones/flavonols and has evolved independently from flavone/flavonol UGTs identified in Arabidopsis thaliana
    Phytochemistry (IF 3.186) Pub Date : 2018-11-09
    Alexander E. Wilson, Sheng Wu, Li Tian

    UDP-dependent glycosyltransferases (UGTs) convert aglycones into more stable, bioactive, and structurally diverse glycosylated derivatives. Pomegranate (Punica granatum L.) produces various glycosylated phenolic metabolites, e.g. hydrolyzable tannins (HTs), anthocyanins, and flavonoids, and constitutes an excellent system for investigating the corresponding UGT activities. Here we report the cloning and functional characterization of a pomegranate UGT, PgUGT95B2, which is highly active towards flavones and flavonols and can glycosylate at more than one position in the substrate molecule. Particularly, PgUGT95B2 has the strongest activity towards tricetin (flavone with a tri-hydroxylated B-ring) and can act at the 4‘-O position of its B-ring. In addition, PgUGT95B2 was able to glycosylate flavones present in pomegranate metabolite extracts. Conversely, PgUGT95B2 did not produce a galloylglucose ester (precursor for HT biosynthesis) or anthocyanins in enzyme assays. Our phylogenetic analysis suggested an independent evolution of PgUGT95B2 and flavone/flavonol UGTs identified in the model plant Arabidopsis thaliana through convergent evolution or gene loss.

    更新日期:2018-11-12
  • Funiculosone, a substituted dihydroxanthene-1,9-dione with two of its analogues produced by an endolichenic fungus Talaromyces funiculosus and their antimicrobial activity
    Phytochemistry (IF 3.186) Pub Date : 2018-11-09
    Srichanadan Padhi, Marco Masi, Alessio Cimmino, Angela Tuzi, Subhrakanta Jena, Kumananda Tayung, Antonio Evidente
    更新日期:2018-11-10
Some contents have been Reproduced with permission of the American Chemical Society.
Some contents have been Reproduced by permission of The Royal Society of Chemistry.
导出
化学 • 材料 期刊列表