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1.
Seeds of Hypericum perforatum and H. tetrapterum were extracted with dichloromethane and methanol and investigated by chromatographic and mass spectrometric methods. Both species yielded a fatty oil fraction amounting to 30.5% and 18.0% of the seed weight, respectively. Linoleic acid (C18:2n‐6) was shown to be the predominant fatty acid constituent. Moreover, xanthone derivatives, i.e. tetrahydroxyxanthones (THX), xanthone‐glycosides and xanthone‐sulfonates, were assigned in methanolic extracts. For structure elucidation, one representative xanthone, namely 1,3,6,7‐THX, was synthesized and analyzed via HPLC‐DAD/MSn and GC/MS. Total THX contents were quantitated applying a validated HPLC‐DAD method, resulting in 1.25 g/kg (H. perforatum) and 0.27 g/kg (H. tetrapterum), respectively. Moreover, the free radical scavenging capacity of the methanol extracts was tested using the DPPH antioxidant assay. Both, H. perforatum (IC50 = 8.7 mg/l) and 1,3,6,7‐THX (IC50 = 3.0 mg/l), exhibited good DPPH free radical scavenging activity compared to Trolox (IC50 = 6.6 mg/l).  相似文献   

2.
Five new cyclohexadepsipeptides termed as enniatins R – V ( 1 – 5 ) and seven known cyclohexadepsipeptides ( 6 – 12 ) were isolated from the solid culture of Fusarium proliferatum, a fungus isolated from the cadaver of an unidentified insect collected in Tibet. Their structures were elucidated by NMR and MS spectroscopic analysis. The X‐ray single‐crystal structure of 6 was reported for the first time. Enniatins R and S represented the first enniatins incorporating with an unusual 2,3‐dihydroxy‐isovaleric acid (Div) residue. The cytotoxicity and autophagy‐inducing activities of 1 – 12 were evaluated in vitro. Beauvenniatin F ( 11 ) exhibited strong cytotoxicity against K562/A (adriamycin‐resistant K562) with IC50 value of 3.78 μm , and also autophagy‐inducing activity at the concentration of 20 μm in GFP‐LC3 stable HeLa cells.  相似文献   

3.
Plants from the Brassicaceae family are known to contain secondary metabolites called glucosinolates. Our goal was to establish by LC/MS the glucosinolate profile of seeds of three Brassicaceae species known to hyperaccumulate heavy metals. We investigated Alyssum fallacinum auct. non Hausskn ., Iberis intermedia Guers ., and Noccaea caerulescens (J. Presl & C. Presl ) F. K. Mey . Our results indicate that A. fallacinum seeds contain glucoiberin and glucoibervirin, which had not been previously identified in this plant. Furthermore, we report for the first time the presence of glucoiberin, glucoibervirin, glucotropaeolin, and sinigrin in I. intermedia. We have detected for the first time glucoconringiin in N. caerulescens. In addition, glucosinalbin, 4‐hydroxyglucobrassicin, and glucomoringin were also detected.  相似文献   

4.
Six lignans including two new lignans were obtained as the principal components of the Forsythia koreana flowers via silica gel (SiO2), octadecyl SiO2 (ODS) as well as Sephadex LH‐20 column chromatography. In addition to two new lignans, named koreanaside A ((7R,8S,7′R,8′S)‐7,7‐diepoxy‐5‐hydroxy‐3,3‐dimethoxylignan 4‐Oβ‐d ‐glucopyranoside) and koreanaside B ((7R,8S,7′S,8′R)‐7,9‐epoxy‐9,5,7‐trihydroxy‐3,3‐dimethoxylignan 4‐Oβ‐d ‐glucopyranoside), four known lignans were identified to be (+)‐phylligenin, (?)‐epipinoresinol, pinoresinol, and tinosposide A. The structures and absolute configurations of koreanasides A and B were established by means of analysis of spectroscopic data (NMR, IR, FAB‐MS, and CD), whereas the structures of known lignans were identified by comparison their NMR and MS values with those in the reported literature. Their chemical structures including configuration were established by means of analysis of spectroscopic data (NMR, IR, FAB‐MS, and CD) but also comparison of their NMR and MS values with those in the reported literature. This is the first article for isolation of six lignans of Fkoreana flowers. Koreanasides A and B showed high radical scavenging activity with oxygen radical absorbance capacity (ORAC) values of 0.97 ± 0.01 and 1.02 ± 0.01, respectively. Koreanaside A also prohibited expressing VCAM‐1 in MOVAS cells with 80.5% at 25 mg/mL.  相似文献   

5.
Quantification of fatty acids has been crucial to elucidate lipid biosynthesis pathways in plants. To date, fatty acid identification and quantification has relied mainly on gas chromatography (GC) coupled to flame ionization detection (FID) or mass spectrometry (MS), which requires the derivatization of samples and the use of chemical standards for annotation. Here we present an alternative method based on a simple procedure for the hydrolysis of lipids, so that fatty acids can be quantified by liquid chromatography mass spectrometry (LC‐MS) analysis. Proper peak annotation of the fatty acids in the LC‐MS‐based methods has been achieved by LC‐MS measurements of authentic standard compounds and elemental formula annotation supported by 13C isotope‐labeled Arabidopsis. As a proof of concept, we have compared the analysis by LC‐MS and GC‐FID of two previously characterized Arabidopsis thaliana knock‐out mutants for FAD6 and FAD7 desaturase genes. These results are discussed in light of lipidomic profiles obtained from the same samples. In addition, we performed untargeted LC‐MS analysis to determine the fatty acid content of two diatom species. Our results indicate that both LC‐MS and GC‐FID analyses are comparable, but that because of higher sensitivity and selectivity the LC‐MS‐based method allows for a broader coverage and determination of novel fatty acids.  相似文献   

6.
In the present study, an ayurvedic medicinal plant, Anthocephalus cadamba (Roxb .) Miq . commonly known as ‘Kadamb’ was explored for its potential against oxidative stress and cancer. The fractions namely AC‐4 and ACALK (alkaloid rich fraction) were isolated from A. cadamba leaves by employing two different isolation methods and evaluated for their in vitro antioxidant and antiproliferative activity. The structure of the isolated AC‐4 was characterized tentatively as dihydrocadambine by using various spectroscopic techniques such as ESI‐QTOF‐MS, 1H‐ and 13C‐NMR, DEPT, COSY, HMQC, and HMBC. Results of various antioxidant assays viz. 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH), ABTS cation radical, superoxide anion radical scavenging, and plasmid nicking assay demonstrated that both the fractions viz. AC‐4 and ACALK possess ability to scavenge DPPH, ABTS radicals and effectively protected plasmid pBR322 DNA from damage caused by hydroxyl radicals. Further, when both fractions were evaluated for their potential to suppress growth of HeLa and COLO 205 cells, only ACALK fraction showed antiproliferative effects. ACALK exhibited GI50 of 205.98 and 99.54 μg/ml in HeLa and COLO 205 cell lines, respectively. Results of Hoechst staining in cervical carcinoma (HeLa) cells confirmed that ACALK induced cell death in HeLa cells via apoptotic mode. Both the fractions also inhibited COX‐2 enzyme activity.  相似文献   

7.
A new monoterpene lactone, (1R,4R,5R,8S)‐8‐hydroxy‐4,8‐dimethyl‐2‐oxabicyclo[3.3.1]nonan‐3‐one ( 1 ), along with one related known compound, (2R)‐2‐[(1R)‐4‐methylcyclohex‐3‐en‐1‐yl]propanoic acid ( 2 ), were isolated from the liquid culture of the plant endophytic fungus Pestalotiopsis foedan obtained from the branch of Bruguiera sexangula. The structure and absolute configuration of 1 were determined on the basis of extensive analysis of NMR spectra combined with computational methods via calculation of the optical rotation (OR) and 13C‐NMR. Both compounds exhibited strong antifungal activities against Botrytis cinerea and Phytophthora nicotianae with MIC values of 3.1 and 6.3 μg/ml, respectively, which are comparable to those of the known antifungal drug ketoconazole. Compound 2 also showed modest antifungal activity against Candida albicans with a MIC value of 50 μg/ml.  相似文献   

8.
Six new pentacyclic triterpenoids were isolated from the fruit of Camptotheca acuminata. The chemical structures of the new compounds were elucidated by extensive spectroscopic analysis including HR‐ESI‐MS, IR, UV, 1D‐ and 2D‐NMR. Moreover, the antibacterial activities of compounds 1 , 2 , 4 , 5 , and 6 were evaluated against Staphylococcus aureus, Escherichia coli, Bacillus subtilis and Dickeya zeae. All these tested compounds showed moderate antibacterial activity against Bacillus subtilis and Dickeya zeae.  相似文献   

9.
An unusual tetrahydrofuran lignin, zanthplanispine ( 1 ), together with 14 known lignans ( 2 – 15 ) were isolated from the AcOEt‐soluble fraction from the MeOH extract of Z. planispinum roots. The structures of 1 was elucidated on the basis of 1D‐ and 2D‐NMR experiments as well as HR‐ESI‐MS analysis. The known compounds were identified by the comparison of their NMR data with previously reported in the literatures. Bioassay showed that compounds 1 – 4 could inhibit nitric oxide (NO) production in lipopolysaccharide (LPS) stimulated RAW 264.7 cells. In particular, compound 1 showed significant inhibitory activity with an IC50 value of 36.8 μm .  相似文献   

10.
Activity‐guided fractionation strategy was used to investigate chemical constituents from the roots of Podocarpus macrophyllus. Successfully, two new norditerpenes, 2β‐hydroxymakilactone A ( 1 ) and 3β‐hydroxymakilactone A ( 2 ), along with ten known analogues ( 3  –  12 ) were isolated. The structures of 1 and 2 were elucidated by spectroscopic analysis including 1D‐, 2D‐NMR, and HR‐ESI‐MS data. The previously reported structure of 2,3‐dihydro‐2α‐hydroxypodolide was revised as 2,3‐dihydro‐2β‐hydroxypodolide ( 3 ) by spectroscopic analysis, and was further confirmed by X‐ray crystallographic analysis. Cytotoxic activities of all isolated compounds against five human solid tumour cell lines (AGS, HeLa, MDA‐MB‐231, HepG‐2, and PANC‐1) were evaluated. All of them exhibited anti‐proliferative activities (IC50 = 0.3 – 27 μm ), except for 10 . Compounds 1 , 4 , 5 , 6 , and 8 exhibited potent inhibitory activities with IC50 < 1 μm against HeLa and AGS cells.  相似文献   

11.
The increasing consumption of natural products lead us to discover and study new plant materials, such as conifer seeds and cones, which could be easily available from the forest industry as a waste material, for their potential uses. The chemical composition of the essential oils of Picea pungens and Picea orientalis was fully characterized by GC and GC/MS methods. Seed and cone oils of both tree species were composed mainly of monoterpene hydrocarbons, among which limonene, α‐ and β‐pinene were the major, but in different proportions in the examined conifer essential oils. The levorotary form of chiral monoterpene molecules was predominant over the dextrorotary form. The composition of oils from Ppungens seeds and cones was similar, while the hydrodistilled oils of Porientalis seeds and cones differed from each other, mainly by a higher amount of oxygenated derivatives of monoterpenes and by other higher molar mass terpenes in seed oil. The essential oils showed mild antimicrobial action, however Porientalis cone oil exhibited stronger antimicrobial properties against tested bacterial species than those of Ppungens. Effects of the tested cone essential oils on human skin fibroblasts and microvascular endothelial cells (HMEC‐1) were similar: in a concentration of 0 – 0.075 μl/ml the oils were rather safe for human skin fibroblasts and 0 – 0.005 μl/ml for HMEC‐1 cells. IC50 value of Picea pungens oils was 0.115 μl/ml, while that of Picea orientalis was 0.105 μl/ml. The value of IC50 of both oils were 0.035 μl/ml for HMEC‐1 cells. The strongest effect on cell viability had the oil from Picea orientalis cones, while on DNA synthesis the oil from Picea pungens cones.  相似文献   

12.
Five novel iridoid glycosides, avellanedaesides A‐E ( 1  –  5 ) were isolated from the H2O extract of Tabebuia avellanedae. Their structures were determined on the basis of NMR and MS analysis. Isolated compounds suppressed inflammatory cytokine, tumor‐necrosis factor‐α and interleukin‐1β production in cultured human myeloma THP‐1 cells co‐stimulated with lipopolysaccharide (LPS). In addition, the study revealed iridoid glycosides inhibited the activity of cytochrome CYP3A4 enzyme.  相似文献   

13.
14.
Four new iridoids, 2′‐O‐(E)coumaroylshanzhiside ( 1 ), 6′‐O‐(E)coumaroylshanzhiside ( 2 ), 8α‐butylgardenoside B ( 3 ), 6α‐methoxygenipin ( 4 ), and one new phenylpropanoid glucoside, 5‐(3‐hydroxypropyl)‐2‐methoxyphenyl β‐d ‐glucopyranoside ( 5 ), together with sixteen known compounds, were isolated from the edible flowers of wild Gardenia jasminoides J.Ellis . Their chemical structures were characterized by extensive spectroscopic techniques, including 1D‐ and 2D‐NMR, HR‐ESI‐MS, and CD experiments. The absolute configurations of the new isolates’ sugar moiety were assigned by HPLC analysis of the acid hydrolysates. Furthermore, the antioxidant activities of those isolates were preliminarily evaluated by DPPH scavenging experiment. And comparison of 1H‐NMR spectra for the EtOH extract of Gjasminoides J.Ellis , gardenoside B and geniposide revealed that the flowers of this plant have a considerable content of gardenoside B instead of geniposide in the fruits, indicating different activities and applications in people's daily life.  相似文献   

15.
  • Heavy metal allocation and the mechanism(s) of metal sequestration in different clonal organs, micro‐domains and subcellular structures has not been systematically studied for rhizomatous perennial plants. It is thus pertinent to investigate knowledge of the speciation and distribution characteristics of Cu in Phragmites australis to elucidating the mobility of metals in wetland plants after their uptake via root systems so as to facilitate development of strategies to enhance Cu tolerance.
  • This study investigated the distributions of Cu in P. australis root, stem and leaf using ICP‐MS, synchrotron‐based X‐ray micro‐fluorescence and X‐ray absorption spectroscopy, then evaluated the effects of Cu on cellular structure and ultrastructure via transmission electron microscopy.
  • The results indicate a clear preferential localisation of Cu in the roots as compared with the shoots (stems and leaves). The intensity of Cu in the vascular bundles was higher than that in the surrounding epidermis and the endodermis and parenchyma outside the medullary cavity. The dominant chemical form of Cu in P. australis was similar to Cu citrate.
  • The results suggest that although Cu can be easily transported into the vascular tissues in roots and stems via Cu citrate, most of the metal absorbed by plants is retained in the roots because if its high binding to the cell wall, thus preventing metal translocation to aerial parts of the plants. Therefore, P. australis showed a high capacity to accumulate Cu in roots, being therefore a suitable species for phytostabilisation interventions.
  相似文献   

16.
Three new iridoid glycosides, named involucratosides A – C ( 1  –  3 ), were isolated from the H2O subextract of crude MeOH extract prepared from the aerial parts of Asperula involucrata along with a known iridoid glycoside (adoxoside), three flavone glycosides (apigenin 7‐Oβ‐glucopyranoside, luteolin 7‐Oβ‐glucopyranoside, apigenin 7‐O‐rutinoside) as well as two phenolic acid derivatives (chlorogenic acid and ferulic acid 4‐Oβ‐glucopyranoside). Their chemical structures were established by UV, IR, 1D‐ (1H, 13C and JMOD) and 2D‐ (COSY, HSQC, HMBC and NOESY) NMR experiments and HR‐ESI‐MS. In addition, the crude extract, subextracts and isolates were evaluated for their xanthine oxidase inhibitory and antioxidant activities in in vitro tests. This is the first report on the chemical composition and bioactivities of Ainvolucrata.  相似文献   

17.
Two new sesquiterpene lactones, artelavanolides A ( 1 ) and B ( 2 ), and four known sesquiterpene lactones ( 3 – 6 ) were isolated from the leaves of Artemisia lavandulaefolia. Their structures were elucidated based on the analysis of spectroscopic data (1D, 2D‐NMR and HR‐ESI‐MS). The absolute configuration of 1 was determined by the analysis of single‐crystal X‐ray diffraction data. Artelavanolide A ( 1 ) is a rare sesquiterpene lactone possessing an unusual skeleton with the linkage of Me(14)–C(1) that is probably formed through a rearrangement of the guaiane‐type sesquiterpenoids. Artelavanolide B ( 2 ) is a new highly unsaturated guaianolide. Compounds 1 – 6 were tested for activities on the inhibition of COX‐2 enzyme in vitro. All of compounds exhibited inhibitory activity against COX‐2 with IC50 values ranging from 43.29 to 287.07 μm compared with the positive control, celecoxib (IC50 = 18.10 μm ). Among them, 3 showed the best COX‐2 inhibitory activity with an IC50 value of 43.29 μm .  相似文献   

18.
The study of the MeOH extract of the leaves of Campylospermum excavatum led to the isolation of a nitrile glucoside, named campyloside C ( 1 ) and an original derivative of ochnaflavone, 7‐O‐methylochnaflavone ( 2 ), along with three known biflavonoids, amentoflavone, sequoiaflavone, and sotetsuflavone ( 3 – 5 ). The linkage site of the sub‐units of 2 was confirmed by chemical correlation, after semi‐synthesis of a trimethoxylated derivative of ochnaflavone ( 2a ). The structures of these compounds as well as their relative and absolute configurations were assigned by 1D‐ and 2D‐NMR experiments, HR‐ESI‐MS and Electronic Circular Dichroism (ECD) calculations. A low‐pass J filter HMBC experiment was performed in order to define the configuration of the double bond of 1 . All of the biflavonoids were evaluated against protozoan parasites. Amentoflavone moderately inhibited the promastigote form of Leishmania infantum.  相似文献   

19.
While plants of the genus Dyssodia are used by man to a certain extent, few phytochemical and pharmacological studies have been performed with species of this genus. D. tagetiflora is an endemic plant of Mexico and has been used as fodder. The aim of this research was to isolate and identify the main bioactive components and evaluate the insecticidal, antioxidant, genotoxic and cytoprotective activities of D. tagetiflora. The isolated substances included an essential oil composed of six monoterpenes, and extracts containing two flavonols, three flavonol‐glycosides and four thiophenes. The compounds were characterized using spectroscopic and spectrometric methods, including GC/MS, MS and NMR. The essential oil showed insecticidal activity against Drosophila melanogaster larvae. The methanolic extract of D. tagetiflora (DTME) had strong antioxidant activity against DPPH and ABTS radicals; DTME showed no evidence of genotoxic or cytotoxic effects. In contrast, DTME showed a cytoprotective effect attenuating the formation of H2O2‐induced micronuclei in Vicia faba roots. This report is the first to describe the phytochemical and biological activity of D. tagetiflora.  相似文献   

20.
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