Methyl syringate and isovanilic acid from the bark of Alphonsea elliptica

M. Nur Sidik; Bakri Yuhanis Mhd; Abdul Azziz Saripah Salbiah Syed; Chee Fah Wong; Mastura Ibrahim

doi:10.25303/2512rjce2831

Methyl syringate and isovanilic acid from the bark of Alphonsea elliptica

Research Journal of Chemistry and Environment ◽

10.25303/2512rjce2831 ◽

2021 ◽

Vol 25 (12) ◽

pp. 28-31

Author(s):

M. Nur Sidik ◽

Bakri Yuhanis Mhd ◽

Abdul Azziz Saripah Salbiah Syed ◽

Chee Fah Wong ◽

Mastura Ibrahim

Keyword(s):

Spectroscopic Techniques ◽

Phytochemical Study ◽

Methyl Syringate

A phytochemical study of dichloromethane extract of Alphonsea elliptica has led to the isolation of two compounds previously unreported from the species methyl syringate and isovanilic acid. Stigmasterol which has been previously reported was also isolated. The structures were determined by spectroscopic techniques and by comparison with data reported in the literature. The findings of this study will contribute to the chemotaxonomic and phylogenetic aspects of the Alphonsea sp.

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Two New Oleanane-type Saponins from Hydrocotyle multifida

Natural Product Communications ◽

10.1177/1934578x1801301110 ◽

2018 ◽

Vol 13 (11) ◽

pp. 1934578X1801301

Author(s):

Mayra Rengifo Carrillo ◽

Anne-Claire Mitaine-Offer ◽

Thomas Paululat ◽

Laurent Pouységu ◽

Stéphane Quideau ◽

...

Keyword(s):

Mass Spectrometry ◽

2D Nmr ◽

Spectroscopic Techniques ◽

Phytochemical Study

A phytochemical study of a Venezuelan species Hydrocotyle multifida led to the isolation of five oleanane-type glycosides: two previously undescribed and three known ones. Their structures were established by 2D NMR spectroscopic techniques and mass spectrometry as 3- O-β-D-galactopyranosyl-(1→2)-[α-L-arabinopyranosyl-(1→3)]-β-D-glucuronopyranosyloleanolic acid and 3- O-β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl-(1→2)-β-D-glucuronopyrano-syloleanolic acid. These results represent a significative contribution to the chemotaxonomy of the Hydrocotyle genus.

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New Alkenylresorcinols with Cytotoxic and Antimicrobial Activities from the Leaves of Embelia schimperi

Planta Medica ◽

10.1055/a-1209-3501 ◽

2020 ◽

Vol 86 (17) ◽

pp. 1298-1303

Author(s):

Tatiana Arlette M. Togue ◽

Blanche Laure Ndontsa ◽

Gabin Thierry M. Bitchagno ◽

Anja Schüffler ◽

Till Opatz ◽

...

Keyword(s):

Antimicrobial Properties ◽

Antimicrobial Activities ◽

Spectroscopic Techniques ◽

Ongoing Research ◽

Phytochemical Study ◽

Phenolic Lipids ◽

Cervical Cancer Cells ◽

Hela S3 ◽

Human Cervical Cancer Cells

AbstractA phytochemical study of the methanol extract of the leaves of Embelia schimperi resulted in the isolation of three new alkenylresorcinols, 1 – 3, together with the known analogs 4 – 7. Their structures were established by a combination of spectroscopic techniques. Compounds 1 – 7 exhibited moderate cytotoxic activity against human cervical cancer cells HeLa-S3 and more pronounced antimicrobial properties towards bacteria and filamentous fungi. The present study falls into an ongoing research project on the characterization of bioactive phenolic lipids from plants of the family Primulaceae.

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PHYTOCHEMICAL STUDY ON THE ETHYLACETATE EXTRACT OF THE LEAVES OF Mesua ferrea LINN

Indonesian Journal of Chemistry ◽

10.22146/ijc.21637 ◽

2010 ◽

Vol 8 (2) ◽

pp. 242-244 ◽

Cited By ~ 2

Author(s):

S. M. Mizanur Rahman ◽

Swati Shabnom ◽

M. Abdul Quader ◽

M. Amzad Hossain

Keyword(s):

Spectral Analysis ◽

Medicinal Plant ◽

1H Nmr ◽

Mass Spectroscopy ◽

13C Nmr ◽

Spectroscopic Techniques ◽

Phytochemical Study

Furano-napthyl-hydroxy cyclohexyl type of compound was isolated first times in plant from the ethyl extracts of the leaves of Mesua ferrea. The structure of the compound has been established by the modern spectroscopic techniques such as UV, IR, 1H-NMR, 13C-NMR and mass spectroscopy and identified as 12, 13-furano-8-hydroxy napthyl-6-0-b-2',3',4',6' tetrahydroxy-5',5' dimethyl cyclohexyl ether. Keywords: Mesua ferrea Linn; Euphorbiaceae; Medicinal plant; new compound; spectral analysis

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An Efflux Pumps Inhibitor Significantly Improved the Antibacterial Activity of Botanicals from Plectranthus glandulosus towards MDR Phenotypes

The Scientific World JOURNAL ◽

10.1155/2021/5597524 ◽

2021 ◽

Vol 2021 ◽

pp. 1-8

Author(s):

Gravalain Nanmeni ◽

Alex T. Tedonkeu ◽

Aimé G. Fankam ◽

Armelle T. Mbaveng ◽

Brice E. N. Wamba ◽

...

Keyword(s):

Antibacterial Activity ◽

Efflux Pump ◽

Ethanol Extract ◽

Efflux Pumps ◽

Multidrug Resistant ◽

Spectroscopic Techniques ◽

Efflux Pump Inhibitor ◽

Phytochemical Study ◽

Microdilution Method ◽

Broth Microdilution Method

Bacterial multidrug resistance causes many therapeutic failures, making it more difficult to fight against bacterial diseases. This study aimed to investigate the antibacterial activity of extract, fractions, and phytochemicals from Plectranthus glandulosus (Lamiaceae) against multidrug-resistant (MDR) Gram-negative phenotypes expressing efflux pumps. The crude extract after extraction was subjected to column chromatography, and the structures of the isolated compounds were determined using spectrometric and spectroscopic techniques. Antibacterial assays of samples alone and in the presence of an efflux pump inhibitor (phenylalanine-arginine β-naphthylamide, PAβN) were carried out using the broth microdilution method. The phytochemical study of P. glandulosus plant extract afforded seven major fractions (A–G) which lead to the isolation of seventeen known compounds. The ethanol extract of P. glandulosus was not active at up to 1024 μg/mL, whereas its fractions showed MICs varying from 32 to 512 μg/mL on the studied bacteria. Fraction C of P. glandulosus showed the lowest MIC (32 μg/mL) on E. coli ATCC8739 strain. Fraction D presented the highest activity spectrum by inhibiting the growth of 90% (9/10) of the studied bacteria. The presence of PAβN has improved the activity of extract and all fractions. Overall, the tested phytochemicals showed low activity against the studied bacteria. The overall results obtained in this study show that some fractions from P. glandulosus, mainly fractions C and D, should be investigated more for their possible use to fight against MDR bacteria.

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VEGFR-Mediated Cytotoxic Activity of Pulicaria undulata Isolated Metabolites: A Biological Evaluation and In Silico Study

Life ◽

10.3390/life11080759 ◽

2021 ◽

Vol 11 (8) ◽

pp. 759

Author(s):

Sameh S. Elhady ◽

Reda F. A. Abdelhameed ◽

Salwa H. Zekry ◽

Amany K. Ibrahim ◽

Eman S. Habib ◽

...

Keyword(s):

Vascular Endothelial Growth Factor ◽

Growth Factor ◽

Antiproliferative Activity ◽

Biological Evaluation ◽

New Drugs ◽

Antiangiogenic Agents ◽

Spectroscopic Techniques ◽

Vascular Endothelial ◽

Phytochemical Study ◽

Endothelial Growth Factor

Natural products play a remarkable role not only in the synthesis, design, and discovery of new drugs but also as the most prominent source of drugs and bioactive substances. Adding to the search for new sources of safe innovative antitumor drugs, here we reported a phytochemical study on Pulicaria undulata which revealed promising antiangiogenic agents. Six compounds were isolated and identified as xanthoxyline (1), stigmasterol (2), oleanolic acid (3), salvigenin (4), rhamnetin (5) and dihydroquercetin-4′-methyl ether (6) using nuclear magnetic resonance (NMR) spectroscopic techniques. Compound 3 and 4 are first reported in Pulicaria genus. Both the extract and isolated compounds were evaluated for in vitro antiproliferative activity against breast cancer cell line (MCF-7). In vivo antiproliferative activity against Ehrlich’s ascites carcinoma (EAC) were also assessed. The P. undulata extract and isolates showed significant reduction in tumor weight, decreased both serum vascular endothelial growth factor B (VEGF-B) levels and vascular endothelial growth factor receptor 2 (VEGFR-2) expression significantly compared to the control EAC group, suggesting an antiangiogenic activity through the inhibition of VEGF signaling. Besides, they displayed reduction in CD34 expression, confirming their antiangiogenic effect. Moreover, the potential affinity of isolated compounds to human estrogen nuclear receptor-alpha (hER-α), the most recognized modulator of VEGFR-2 expression, was virtually estimated through molecular modeling studies. The most promising activity profiles were assigned to the investigated flavonoids, compounds 4–6, as well as the alkyl-phenylketone, compound 1. Additionally, these four top active compounds showed respective high to intermediate docking scores while possessing preferential binding with hER-α critical pocket residues. Based on the provided data, these isolated compounds illustrated promising inhibitors of VEGF-stimulated angiogenesis, which could be a possible mechanism for their anticancer activity.

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Differential polarization imaging of sickled cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100102390 ◽

1988 ◽

Vol 46 ◽

pp. 62-63

Author(s):

Marcos F. Maestre

Keyword(s):

Optical Properties ◽

Theoretical Approach ◽

Polarized Light ◽

Polarization Microscopy ◽

Spectroscopic Techniques ◽

Polarization Imaging ◽

Circularly Polarized Light ◽

Circularly Polarized ◽

Microscopic Scale ◽

Chiral Structures

Recently we have developed a form of polarization microscopy that forms images using optical properties that have previously been limited to macroscopic samples. This has given us a new window into the distribution of structure on a microscopic scale. We have coined the name differential polarization microscopy to identify the images obtained that are due to certain polarization dependent effects. Differential polarization microscopy has its origins in various spectroscopic techniques that have been used to study longer range structures in solution as well as solids. The differential scattering of circularly polarized light has been shown to be dependent on the long range chiral order, both theoretically and experimentally. The same theoretical approach was used to show that images due to differential scattering of circularly polarized light will give images dependent on chiral structures. With large helices (greater than the wavelength of light) the pitch and radius of the helix could be measured directly from these images.

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Characterization of intergranular cuprous oxide in polycrystalline YBa2Cu3O7-x

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100106466 ◽

1988 ◽

Vol 46 ◽

pp. 880-881

Author(s):

Bradley L. Thiel ◽

Chan Han R. P. ◽

Kurosky L. C. Hutter ◽

I. A. Aksay ◽

Mehmet Sarikaya

Keyword(s):

Grain Boundary ◽

Cuprous Oxide ◽

Room Temperature ◽

Boundary Phase ◽

Spectroscopic Techniques ◽

Transition Width ◽

Practical Applications ◽

Thin Foils ◽

Superconducting Oxides

The identification of extraneous phases is important in understanding of high Tc superconducting oxides. The spectroscopic techniques commonly used in determining the origin of superconductivity (such as RAMAN, XPS, AES, and EXAFS) are surface-sensitive. Hence a grain boundary phase several nanometers thick could produce irrelevant spectroscopic results and cause erroneous conclusions. The intergranular phases present a major technological consideration for practical applications. In this communication we report the identification of a Cu2O grain boundary phase which forms during the sintering of YBa2Cu3O7-x (1:2:3 compound).Samples are prepared using a mixture of Y2O3. CuO, and BaO2 powders dispersed in ethanol for complete mixing. The pellets pressed at 20,000 psi are heated to 950°C at a rate of 5°C per min, held for 1 hr, and cooled at 1°C per min to room temperature. The samples show a Tc of 91K with a transition width of 2K. In order to prevent damage, a low temperature stage is used in milling to prepare thin foils which are then observed, using a liquid nitrogen holder, in a Philips 430T at 300 kV.

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