Displaying publications 361 - 380 of 538 in total

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  1. Kam TS, Sim KM, Koyano T, Toyoshima M, Hayashi M, Komiyama K
    Bioorg Med Chem Lett, 1998 Jul 07;8(13):1693-6.
    PMID: 9873417
    Four new bisindoles of the vobasine-iboga type, conodiparines A-D were obtained from Tabernaemontana corymbosa which showed appreciable activity in reversing resistance in vincristine-resistant KB cells.
    Matched MeSH terms: Magnetic Resonance Spectroscopy
  2. Luthfi AAI, Tan JP, Isa NFAM, Bukhari NA, Shah SSM, Mahmod SS, et al.
    Bioprocess Biosyst Eng, 2020 Jul;43(7):1153-1169.
    PMID: 32095989 DOI: 10.1007/s00449-020-02311-x
    This study aimed to enhance the crystallizability of bio-based succinic acid for its efficient recovery while maintaining the end product at the highest purity. Immobilization of Actinobacillus succinogenes was initially evaluated based on three different carriers: volcanic glass, clay pebbles, and silica particles. The adsorption capacity of metabolites with a low concentration (10 g/L) and a high concentration (40 g/L) was investigated. It was demonstrated that clay pebbles adsorbed the least succinic acid (
    Matched MeSH terms: Proton Magnetic Resonance Spectroscopy
  3. Bustamam MSA, Pantami HA, Azizan A, Shaari K, Min CC, Abas F, et al.
    Mar Drugs, 2021 Mar 02;19(3).
    PMID: 33801258 DOI: 10.3390/md19030139
    This study was designed to profile the metabolites of Isochrysis galbana, an indigenous and less explored microalgae species. 1H Nuclear Magnetic Resonance (NMR) spectroscopy and Liquid Chromatography-Mass Spectrometry (LCMS) were used to establish the metabolite profiles of five different extracts of this microalga, which are hexane (Hex), ethyl acetate (EtOAc), absolute ethanol (EtOH), EtOH:water 1:1 (AqE), and 100% water (Aq). Partial least square discriminant analysis (PLS-DA) of the generated profiles revealed that EtOAc and Aq extracts contain a diverse range of metabolites as compared to the other extracts with a total of twenty-one metabolites, comprising carotenoids, polyunsaturated fatty acids, and amino acids, that were putatively identified from the NMR spectra. Meanwhile, thirty-two metabolites were successfully annotated from the LCMS/MS data, ten of which (palmitic acid, oleic acid, α-linolenic acid, arachidic acid, cholesterol, DHA, DPA, fucoxanthin, astaxanthin, and pheophytin) were similar to those present in the NMR profile. Another eleven glycerophospholipids were discovered using MS/MS-based molecular network (MN) platform. The results of this study, besides providing a better understanding of I.galbana's chemical make-up, will be of importance in exploring this species potential as a feed ingredient in the aquaculture industry.
    Matched MeSH terms: Magnetic Resonance Spectroscopy
  4. Haezam FN, Awang N, Kamaludin NF, Mohamad R
    Saudi J Biol Sci, 2021 May;28(5):3160-3168.
    PMID: 34025187 DOI: 10.1016/j.sjbs.2021.02.060
    Context: Diphenyltin(IV) diallyldithiocarbamate compound (Compound 1) and triphenyltin(IV) diallyldithiocarbamate compound (Compound 2) are two newly synthesised compounds of organotin(IV) with diallyldithiocarbamate ligands.

    Objective: To assess the cytotoxic effects of two synthesised compounds against HT-29 human colon adenocarcinoma cells and human CCD-18Co normal colon cells.

    Materials and methods: Two successfully synthesised compounds were characterised using elemental (carbon, hydrogen, nitrogen, and sulphur) analysis, Fourier-Transform Infrared (FTIR), and 1H, 13C 119Sn Nucleus Magnetic Resonance (NMR) spectroscopies. The single-crystal structure of both compounds was determined by X-ray single-crystal analysis. The cytotoxicity of the compounds was assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazholium bromide (MTT) assay upon 24 h of treatment. While the mode of cell death was determined based on the externalisation of phosphatidylserine using a flow cytometer.

    Results: The elemental analysis data of the two compounds showed an agreement with the suggested formula of (C6H5)2Sn[S2CN(C3H5)2]2 for Compound 1 and (C6H5)3Sn[S2CN(C3H5)2] for Compound 2. The two major peaks of infrared absorbance, i.e., ν(C = N) and ν(C = S) were detected at the range of 1475-1479 cm-1 and 972-977 cm-1, respectively. The chemical shift of carbon in NCS2 group for Compound 1 and 2 were found at 200.82 and 197.79 ppm. The crystal structure of Compound 1 showed that it is six coordinated and crystallised in monoclinic, P21/c space group. While the crystal structure of Compound 2 is five coordinated and crystallised in monoclinic, P21/c space group. The cytotoxicity (IC50) of the two compounds against HT-29 cell were 2.36 μM and 0.39 μM. Meanwhile, the percentage of cell death modes between 60% and 75% for compound 1 and compound 2 were mainly due to apoptosis, suggesting that both compounds induced growth arrest.

    Conclusion: Our study concluded that the synthesised compounds showed potent cytotoxicity towards HT-29 cell, with the triphenyltin(IV) compound showing the highest effect compared to diphenyltin(IV).

    Matched MeSH terms: Magnetic Resonance Spectroscopy
  5. Mehjabin JJ, Wei L, Petitbois JG, Umezawa T, Matsuda F, Vairappan CS, et al.
    J Nat Prod, 2020 06 26;83(6):1925-1930.
    PMID: 32432877 DOI: 10.1021/acs.jnatprod.0c00164
    Chemical investigation of the organic extract from Moorea bouillonii, collected in Sabah, Malaysia, led to the isolation of three new chlorinated fatty acid amides, columbamides F (1), G (2), and H (3). The planar structures of 1-3 were established by a combination of mass spectrometric and NMR spectroscopic analyses. The absolute configuration of 1 was determined by Marfey's analysis of its hydrolysate and chiral-phase HPLC analysis after conversion and esterification with Ohrui's acid, (1S,2S)-2-(anthracene-2,3-dicarboximido)cyclohexanecarboxylic acid. Compound 1 showed biosurfactant activity by an oil displacement assay. Related known fatty acid amides columbamide D and serinolamide C exhibited biosurfactant activity with critical micelle concentrations of about 0.34 and 0.78 mM, respectively.
    Matched MeSH terms: Magnetic Resonance Spectroscopy
  6. Shreaz S, Shiekh RA, Raja V, Wani WA, Behbehani JM
    Chem Biol Interact, 2016 Mar 05;247:64-74.
    PMID: 26806515 DOI: 10.1016/j.cbi.2016.01.015
    In this study, we have used aldehyde function of cinnamaldehyde to synthesize N, N'-Bis (cinnamaldehyde) ethylenediimine [C20H20N2] and Co(II) complex of the type [Co(C40H40N4)Cl2]. The structures of the synthesized compounds were determined on the basis of physiochemical analysis and spectroscopic data ((1)H NMR, FTIR, UV-visible and mass spectra) along with molar conductivity measurements. Anticandidal activity of cinnamaldehyde its ligand [L] and Co(II) complex was investigated by determining MIC80, time-kill kinetics, disc diffusion assay and ergosterol extraction and estimation assay. Ligand [L] and Co(II) complex are found to be 4.55 and 21.0 folds more efficient than cinnamaldehyde in a liquid medium. MIC80 of Co(II) complex correlated well with ergosterol inhibition suggesting ergosterol biosynthesis to be the primary site of action. In comparison to fluconazole, the test compounds showed limited toxicity against H9c2 rat cardiac myoblasts. In confocal microscopy propidium iodide (PI) penetrates the yeast cells when treated with MIC of metal complex, indicating a disruption of cell membrane that results in imbibition of dye. TEM analysis of metal complex treated cells exhibited notable alterations or damage to the cell membrane and the cell wall. The structural disorganization within the cell cytoplasm was noted. It was concluded that fungicidal activity of Co(II) complex originated from loss of membrane integrity and a decrease in ergosterol content is only one consequence of this.
    Matched MeSH terms: Proton Magnetic Resonance Spectroscopy
  7. Kamada T, Vairappan CS
    Nat Prod Res, 2017 Feb;31(3):333-340.
    PMID: 27707003
    Two new non-halogenated sesquiterpenes, snakeol (1) and snakediol (2) were isolated together with 9 known sesquiterpenes such as (R,Z)-33-dimethyl-5-methylene-4-(3-methylpenta-24-dien-1-yl)cyclohex-1-ene (3), palisol (4), pacifigorgiol (5), palisadin D (6), palisadin A (7), palisadin B (8), 5-acetoxypalisadin B (9), debromolaurinterol (10) and α-bromocuparane (11) from the red algae Laurencia snackeyi. The structures of two new metabolites were determined from their spectroscopic data (IR, 1D and 2D NMR and MS). Compounds 1, 2, 10 and 11 showed strong antibacterial activity against selected human clinical bacterial pathogens.
    Matched MeSH terms: Magnetic Resonance Spectroscopy
  8. Nor Aziyah Bakhari, Siti Nur Amirah Diana Fadzillah, Norain Isa
    MyJurnal
    Tinospora crispa Miers (Menispermaceae) is a climbing vine with stems rich in warts. The plant is called Akar Seruntum or Patawali in Malaysia and is widely used for treating skin complaints, malaria, bacterial abscess, high blood pressure and diabetes. In the present study, the stems of T. crispa were collected from the locality and succesively extracted with petroleum ether, followed by chloroform and ethanol. The insecticidal active extract (ethanol extract) was subjected to column chromatography of silica gel eluted with a gradient mobile phase containing hexane, chloroform and ethanol. Among the chemical constituents isolated are n-tetracosyl trans-ferulate and n-octacosyl alcohol, along with three known aporphine alkaloids; N-formylnornuciferine, N-acetylnornuciferine and lysicamine. All compounds were identified by comparing their spectroscopic data (UV, IR, 1H NMR, MS) with data from corresponding values in the literature. Isolation of n-tetracosyl trans-ferulate and noctacosyl alcohol is reported the first time for T. crispa.
    Matched MeSH terms: Proton Magnetic Resonance Spectroscopy
  9. Tani K, Kamada T, Phan CS, Vairappan CS
    Nat Prod Res, 2019 Dec;33(23):3343-3349.
    PMID: 29772929 DOI: 10.1080/14786419.2018.1475387
    Three new cembrane diterpenes, nephthecrassocolides A-B (1-2) and 6-acetoxy nephthenol acetate (3) along with three known compounds, 6-acetoxy-7,8-epoxy nephthenol acetate (4), epoxy nephthenol acetate (5) and nephthenol (6) were isolated from one population of Nephthea sp. Their structures were elucidated based on spectroscopic data analysis and the antifungal activities of compounds 1-6 were evaluated.
    Matched MeSH terms: Magnetic Resonance Spectroscopy
  10. Maulidiani M, Mediani A, Abas F, Park YS, Park YK, Kim YM, et al.
    Talanta, 2018 Jul 01;184:277-286.
    PMID: 29674043 DOI: 10.1016/j.talanta.2018.02.084
    Persimmon (Diospyros kaki L.) is one of the most important fruits that has been consumed for its medicinal properties due to the presence of some active metabolites, particularly polyphenols and carotenoids. Previously described methods, including HPLC, were limited in the determination of metabolites in different persimmon varieties. The present study shows the evaluation and the differences among persimmon polar and non-polar extracts by 1H NMR-based metabolomics approach. The hierarchical clustering analysis (HCA) based on score values of principal component analysis (PCA) model was used to analyze the important compounds in investigated fruits. The 1H NMR spectrum of persimmon chloroform (CDCl3) extracts showed different types of compounds as compared to polar methanol-water (CD3OD-D2O) ones. Persimmons growing in Israel were clustered different from those growing in Korea with the abundance of phenolic compounds (gallic, caffeic and protocathecuic acids), carotenoids (β-cryptoxanthin, lutein, and zeaxanthin), amino acids (alanine), maltose, uridine, and fatty acids (myristic and palmitoleic acids). Glucose, choline and formic acid were more prominent in persimmon growing in Korea. In CD3OD-D2O and CDCl3 persimmon extracts, 43 metabolites were identified. The metabolic differences were shown as well on the results of bioactivities and antioxidant capacities determined by ABTS, FRAP, CUPRAC and DPPH assays. The presented methods can be widely used for quantitation of multiple compounds in many plant and biological samples especially in vegetables and fruits.
    Matched MeSH terms: Proton Magnetic Resonance Spectroscopy
  11. Jeyamogan S, Khan NA, Anwar A, Shah MR, Siddiqui R
    SAGE Open Med, 2018;6:2050312118781962.
    PMID: 30034805 DOI: 10.1177/2050312118781962
    Objectives: To synthesize novel compounds belonging to Benzodioxane, Naphthalene diimide, Aminophenol derivatives and Porphyrin classes and test their potential anticancer properties.

    Methods: Several compounds were synthesized and their molecular identity was confirmed using nuclear magnetic resonance. Potential anticancer properties were determined using cytopathogenicity assays and growth inhibition assays using cervical cancer cells (HeLa). Cells were incubated with different concentrations of compounds belonging to Benzodioxane, Naphthalene diimide, Aminophenol derivatives and Porphyrins and effects were determined. HeLa cells cytopathogenicity was determined by measuring lactate dehydrogenase release using cytotoxicity detection assay. Growth inhibition assays were performed by incubating 50% semi-confluent HeLa cells with Benzodioxane, Naphthalene diimide, Aminophenol derivatives and Porphyrin compounds and HeLa cell proliferation was observed. Growth inhibition and host cell death were compared in the presence and absence of drugs.

    Results: Cytopathogenicity assays showed that the selected compounds were cytotoxic against HeLa cells, killing up to 90% of cells. Growth inhibition assays exhibited 100% growth inhibition. These effects are likely via oxidative stress, production of reactive oxygen species, changes in cytosolic and intracellular calcium/adenine nucleotide homeostasis, inhibition of ribonucleotide reductase/cyclooxygenase and/or glutathione depletion.

    Conclusions: Benzodioxane, Naphthalene diimide, Aminophenol derivatives and Porphyrins exhibited potent anticancer properties. These findings are promising and should pave the way in the rationale development of anticancer drugs. Using different cancer cell lines, future studies will determine their potential as anti-tumour agents as well as their precise molecular mode of action.

    Matched MeSH terms: Magnetic Resonance Spectroscopy
  12. Saswati, Adão P, Majumder S, Dash SP, Roy S, Kuznetsov ML, et al.
    Dalton Trans, 2018 Aug 21;47(33):11358-11374.
    PMID: 30059099 DOI: 10.1039/c8dt01668b
    The synthesis and characterization of an oxidovanadium(iv) [VIVO(L)(acac)] (1) and of two dioxidovanadium(v) [VVO2(L')] (2) and [VVO2(L)] (2a) complexes of the Schiff base formed from the reaction of 4-(p-fluorophenyl) thiosemicarbazone with pyridine-2-aldehyde (HL) are described. The oxidovanadium(iv) species [VIVO(L)(acac)] (1) was synthesized by the reaction of VIVO(acac)2 with the thiosemicarbazone HL in refluxing ethanol. The recrystallization of [VIVO(L)(acac)] (1) in DMF, CH3CN or EtOH gave the same product i.e. the dioxidovanadium(v) complex [VVO2(L)] (2a); however, upon recrystallization of 1 in DMSO a distinct compound [VVO2(L')] (2) was formed, wherein the original ligand L- is transformed to a rearranged one, L'-. In the presence of DMSO the ligand in complex 1 is found to undergo methylation at the carbon centre attached to imine nitrogen (aldimine) and transformed to the corresponding VVO2-species through in situ reaction. The synthesized HL and the metal complexes were characterized by elemental analysis, IR, UV-Vis, NMR and EPR spectroscopy. The molecular structure of [VVO2(L')] (2) was determined by single crystal X-ray crystallography. The methylation of various other ligands and complexes prepared from different vanadium precursors under similar reaction conditions was also attempted and it was confirmed that the imine methylation observed is both ligand and metal precursor specific. Complexes 1 and 2 show in vitro insulin-like activity against insulin responsive L6 myoblast cells, higher than VIVO(acac)2, with complex 1 being more potent. In addition, the in vitro cytotoxicity studies of HL, and of complexes 1 and 2 against the MCF-7 and Vero cell lines were also done. The ligand is not cytotoxic and complex 2 is significantly more cytotoxic than 1. DAPI staining experiments indicate that an increase in the time of incubation and an increase of concentration of the complexes lead to the increase in cell death.
    Matched MeSH terms: Magnetic Resonance Spectroscopy
  13. Xu J, Zheng X, Cheng KK, Chang X, Shen G, Liu M, et al.
    Sci Rep, 2017 03 30;7:45580.
    PMID: 28358020 DOI: 10.1038/srep45580
    Chronic atrophic gastritis (CAG) is a common gastrointestinal disease which has been considered as precancerous lesions of gastric carcinoma. Previously, electro-acupuncture stimulation has been shown to be effective in ameliorating symptoms of CAG. However the underlying mechanism of this beneficial treatment is yet to be established. In the present study, an integrated histopathological examination along with molecular biological assay, as well as 1H NMR analysis of multiple biological samples (urine, serum, stomach, cortex and medulla) were employed to systematically assess the pathology of CAG and therapeutic effect of electro-acupuncture stimulation at Sibai (ST 2), Liangmen (ST 21), and Zusanli (ST 36) acupoints located in the stomach meridian using a rat model of CAG. The current results showed that CAG caused comprehensive metabolic alterations including the TCA cycle, glycolysis, membrane metabolism and catabolism, gut microbiota-related metabolism. On the other hand, electro-acupuncture treatment was found able to normalize a number of CAG-induced metabolomics changes by alleviating membrane catabolism, restoring function of neurotransmitter in brain and partially reverse the CAG-induced perturbation in gut microbiota metabolism. These findings provided new insights into the biochemistry of CAG and mechanism of the therapeutic effect of electro-acupuncture stimulations.
    Matched MeSH terms: Magnetic Resonance Spectroscopy
  14. Shahfiza N, Osman H, Hock TT, Abdel-Hamid AZ
    Acta Biochim. Pol., 2017;64(2):215-219.
    PMID: 28350402 DOI: 10.18388/abp.2015_1224
    BACKGROUND: Dengue is one of the major public health problems in the world, affecting more than fifty million cases in tropical and subtropical region every year. The metabolome, as pathophysiological end-points, provide significant understanding of the mechanism and progression of dengue pathogenesis via changes in the metabolite profile of infected patients. Recent developments in diagnostic technologies provide metabolomics for the early detection of infectious diseases.

    METHODS: The mid-stream urine was collected from 96 patients diagnosed with dengue fever at Penang General Hospital (PGH) and 50 healthy volunteers. Urine samples were analyzed with proton nuclear magnetic resonance (1H NMR) spectroscopy, followed by chemometric multivariate analysis. NMR signals highlighted in the orthogonal partial least square-discriminant analysis (OPLS-DA) S-plots were selected and identified using Human Metabolome Database (HMDB) and Chenomx Profiler. A highly predictive model was constructed from urine profile of dengue infected patients versus healthy individuals with the total R2Y (cum) value 0.935, and the total Q2Y (cum) value 0.832.

    RESULTS: Data showed that dengue infection is related to amino acid metabolism, tricarboxylic acid intermediates cycle and β-oxidation of fatty acids. Distinct variations in certain metabolites were recorded in infected patients including amino acids, various organic acids, betaine, valerylglycine, myo-inositol and glycine.

    CONCLUSION: Metabolomics approach provides essential insight into host metabolic disturbances following dengue infection.

    Matched MeSH terms: Magnetic Resonance Spectroscopy
  15. Saravanakumar K, Mandava S, Chellia R, Jeevithan E, Babu Yelamanchi RS, Mandava D, et al.
    Microb Pathog, 2018 Oct 10;126:19-26.
    PMID: 30316006 DOI: 10.1016/j.micpath.2018.10.011
    The present study aimed to purify and identify the metabolites from T. atroviride using high-performance liquid chromatography (HPLC) and 1H and 13C nuclear magnetic resonance spectrometer (NMR) followed by analyzing their toxicological, antibacterial and anticancer properties. This work identified two metabolites - TM1 and TM2. TM1 was in two forms: (i) 1, 3-dione-5, 5-dimethylcyclohexane; and, (ii) 2-enone-3hydroxy -5,5-dimethylcylohex, while TM2 was 4H-1,3-dioxin-4-one-2,3,6-trimethyl. These metabolites did not exhibit any irritant or allergic reaction as revealed by HET- CAM test. TM2 significantly inhibited the growth of H. pylori and Shigella toxin producing Escherichia coli (STEC) as evident by in vitro and microscopic observations of bacterial cell death. TM2 also induced the cell death and cytotoxicity, as revealed by cell viability test and western blot analysis. According to microscopic, flow cytometer and western blot analysis, TM2 treated cells displayed higher ROS, cell death, and apoptosis-related protein expression than TM1 and control. This study concluded that TM2 derived from T. atroviride was a potential therapeutic agent for anti-prostate cancer and antibiotic agent against MDR- H. pylori and STEC and it is also recommended to carry out further in vivo animal model experiments with improved stability of the metabolites for future pharmaceutical trails.
    Matched MeSH terms: Magnetic Resonance Spectroscopy
  16. Fam SY, Chee CF, Yong CY, Ho KL, Mariatulqabtiah AR, Lau HY, et al.
    Int J Mol Sci, 2019 Oct 03;20(19).
    PMID: 31623310 DOI: 10.3390/ijms20194903
    Virus-like nanoparticles (VLNPs) have been studied extensively as nanocarriers for targeted drug delivery to cancer cells. However, VLNPs have intrinsic drawbacks, in particular, potential antigenicity and immunogenicity, which hamper their clinical applications. Thus, they can be eliminated easily and rapidly by host immune systems, rendering these nanoparticles ineffective for drug delivery. The aim of this study was to reduce the antigenicity of hepatitis B core antigen (HBcAg) VLNPs by shielding them with a hydrophilic polymer, poly(2-ethyl-2-oxazoline) (PEtOx). In the present study, an amine-functionalized PEtOx (PEtOx-NH2) was synthesized using the living cationic ring-opening polymerization (CROP) technique and covalently conjugated to HBcAg VLNPs via carboxyl groups. The PEtOx-conjugated HBcAg (PEtOx-HBcAg) VLNPs were characterized with dynamic light scattering and UV-visible spectroscopy. The colloidal stability study indicated that both HBcAg and PEtOx-HBcAg VLNPs maintained their particle size in Tris-buffered saline (TBS) at human body temperature (37 °C) for at least five days. Enzyme-linked immunosorbent assays (ELISA) demonstrated that the antigenicity of PEtOx-HBcAg VLNPs reduced significantly as compared with unconjugated HBcAg VLNPs. This novel conjugation approach provides a general platform for resolving the antigenicity of VLNPs, enabling them to be developed into a variety of nanovehicles for targeted drug delivery.
    Matched MeSH terms: Magnetic Resonance Spectroscopy
  17. Kadir MA, Ramli R, Yusof MSM, Ismail N, Ngah N, Haris NSH
    Data Brief, 2019 Dec;27:104651.
    PMID: 31700958 DOI: 10.1016/j.dib.2019.104651
    This paper provided comprehensive data on spectroscopic and antibacterial activities of thioureido compounds which are relevant with research article entitled "Synthesis, Spectroscopic Studies and Antibacterial Activity of New Lauroyl Thiourea Amino Acid Derivatives" [1]. Based on the reported study, four new thioureido derivatives, namely 3-(3-dodecanoyl-thioureido)propionic acid (R1), 2-(3-dodecanoyl-thioureido)-3-methyl butyric acid (R2), (3-dodecanoyl-thioureido)acetic acid (R3) and 2-(3-dodecanoyl-thioureido)-3-phenyl propionic acid (R4) were characterized by elemental analysis, Fourier Transform Infrared (FTIR), 1H Nuclear Magnetic Resonance (1H NMR) and 13C Nuclear Magnetic Resonance (13C NMR), and Ultraviolet Visible spectroscopy (UV-Vis). The preliminary results from antibacterial assay which were tested against Gram-positive bacteria such as Bacillus subtilis, Staphylococcus epidermidis, Staphylococcus aureus and Gram-negative bacteria such as Escherichia coli, Salmonella typhimurium are also described.
    Matched MeSH terms: Carbon-13 Magnetic Resonance Spectroscopy
  18. Ting T, Crouse K, Ahmad H
    Sains Malaysiana, 2015;44:619-628.
    Three novel ruthenium(II) complexes of the general formula [Ru(II)(bpy)2
    L]2+ were synthesized, where L =
    1,10-phenanthroline derivatives of position 2 imidazole having 3,4-didecyloxy-phenyl (ddip), 3,4-ditetradecyloxy-phenyl
    (dtip) and 3,4-dihexadecyloxy-phenyl (dhip). All complexes were characterized by elemental analysis, 1
    H-NMR and ESI-MS.
    Their photophysical properties have also been studied by UV-visible spectroscopy and fluorescence spectroscopy. The
    complexes exhibit Ru(II) metal centered emission at approximately 610 nm in acetonitrile solution at room temperature. DNA
    binding studies were carried out by UV-visible titration, luminescence titration and viscosity studies. The results indicated
    that [Ru(bpy)2
    (ddip)]2+ binds to CT-DNA by partial intercalation mode, while [Ru(bpy)2
    (dtip)]2+ and [Ru(bpy)2
    (dhip)]2+
    bind intercalatively via extended ligands.
    Matched MeSH terms: Magnetic Resonance Spectroscopy
  19. He P, Dong Z, Wang Q, Zhan QP, Zhang MM, Wu H
    J Nat Prod, 2019 02 22;82(2):169-176.
    PMID: 30714735 DOI: 10.1021/acs.jnatprod.8b00238
    A polysaccharide, Ali-1, was isolated from the roots of Eurycoma longifolia, a popular traditional medicinal herb in Malaysia. The structure of Ali-1 was characterized by monosaccharide, methylation, and NMR data analyses. The average molecular weight of Ali-1 is 14.3 ku, and it is composed of arabinose (14.31%), xylose (57.69%), galacturonic acid (13.03%), and glucuronic acid (14.86%). The main chain comprises (1→4)-linked xylose residues. It has branch points in the main chain; (1→2,4)-linked xylose residues, 1,2-linked glucuronic acid residues, and 1,2-linked arabinose residues form the branches, and the branches are terminated with T-linked galacturonic acid residues and T-linked arabinose residues. Ali-1 significantly improves the pinocytic and phagocytic abilities of RAW264.7 cells and facilitates cytokine secretion according to an immunostimulation assay. These results demonstrate that Ali-1 has potential as a functional supplement for people with compromised immune systems.
    Matched MeSH terms: Magnetic Resonance Spectroscopy
  20. Rahman NA, Abu Hanifah S, Mobarak NN, Su'ait MS, Ahmad A, Shyuan LK, et al.
    PLoS One, 2019;14(2):e0212066.
    PMID: 30768616 DOI: 10.1371/journal.pone.0212066
    For the past decade, much attention was focused on polysaccharide natural resources for various purposes. Throughout the works, several efforts were reported to prepare new function of chitosan by chemical modifications for renewable energy, such as fuel cell application. This paper focuses on synthesis of the chitosan derivative, namely, O-nitrochitosan which was synthesized at various compositions of sodium hydroxide and reacted with nitric acid fume. Its potential as biopolymer electrolytes was studied. The substitution of nitro group was analyzed by using Attenuated Total Reflectance Fourier Transform Infra-Red (ATR-FTIR) analysis, Nuclear Magnetic Resonance (NMR) and Elemental Analysis (CHNS). The structure was characterized by X-ray Diffraction (XRD) and its thermal properties were examined by using differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). Whereas, the ionic conductivity of the samples was analyzed by electrochemical impedance spectroscopy (EIS). From the IR spectrum results, the nitro group peaks of O-nitrochitosan, positioned at 1646 and 1355 cm-1, were clearly seen for all pH media. At pH 6, O-nitrochitosan exhibited the highest degree of substitution at 0.74 when analyzed by CHNS analysis and NMR further proved that C-6 of glucosamine ring was shifted to the higher field. However, the thermal stability and glass transition temperatures were decreased with acidic condition. The highest ionic conductivity of O-nitrochitosan was obtained at ~10-6 cm-1. Overall, the electrochemical property of new O-nitrochitosan showed a good improvement as compared to chitosan and other chitosan derivatives. Hence, O-nitrochitosan is a promising biopolymer electrolyte and has the potential to be applied in electrochemical devices.
    Matched MeSH terms: Magnetic Resonance Spectroscopy
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