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Sample records for biologically active binuclear

  1. Binuclear biologically active Co(II) complexes with octazamacrocycle and aliphatic dicarboxylates

    NASA Astrophysics Data System (ADS)

    Tanasković, S. B.; Vučković, G.; Antonijević-Nikolić, M.; Stanojković, T.; Gojgić-Cvijović, G.

    2012-12-01

    Four new cationic Co(II) complexes with N,N',N'',N'''-tetrakis (2-pyridylmethyl)-1,4,8,11-tetraazacyclotetradecane (tpmc) and dianion of one the aliphatic dicarboxylic acids: butanedioic acid (succinic) acid = succH2, pentanedioic (glutaric) acid = gluH2, hexanedioic acid (adipic) acid = adipH2 or decanedioic acid (sebacic) acid = sebH2 of general formula [Co2(L)(tpmc)](ClO4)2ṡxY, L2- = succ, x = 1, Y = H2O; L = glu, x = 1, Y = H2O; L = adip, x = 1.5, Y = H2O; L = seb, x = 1, Y = CH3CN were isolated. The composition and charge are proposed based on elemental analyses (C, H, N) and electrical conductivity measurements. UV-Vis and FTIR spectral data and magnetic moments were in accordance with high-spin Co(II) state. It is proposed that in all complexes Co(II) is hexa-coordinated out of cyclam ring and that both carboxylic groups from dicarboxylate bridge participate in coordination. Oxygens from one group are most likely bonded to the same Co(II) ion thus forming a four-membered ring. The in vitro antibacterial/antiproliferative activities of the complexes were in some cases enhanced compared with the simple Co(II) salt and free ligands, tested as controls.

  2. O2 activation by binuclear Cu sites: Noncoupled versus exchange coupled reaction mechanisms

    NASA Astrophysics Data System (ADS)

    Chen, Peng; Solomon, Edward I.

    2004-09-01

    Binuclear Cu proteins play vital roles in O2 binding and activation in biology and can be classified into coupled and noncoupled binuclear sites based on the magnetic interaction between the two Cu centers. Coupled binuclear Cu proteins include hemocyanin, tyrosinase, and catechol oxidase. These proteins have two Cu centers strongly magnetically coupled through direct bridging ligands that provide a mechanism for the 2-electron reduction of O2 to a µ-2:2 side-on peroxide bridged species. This side-on bridged peroxo-CuII2 species is activated for electrophilic attack on the phenolic ring of substrates. Noncoupled binuclear Cu proteins include peptidylglycine -hydroxylating monooxygenase and dopamine -monooxygenase. These proteins have binuclear Cu active sites that are distant, that exhibit no exchange interaction, and that activate O2 at a single Cu center to generate a reactive CuII/O2 species for H-atom abstraction from the C-H bond of substrates. O2 intermediates in the coupled binuclear Cu enzymes can be trapped and studied spectroscopically. Possible intermediates in noncoupled binuclear Cu proteins can be defined through correlation to mononuclear CuII/O2 model complexes. The different intermediates in these two classes of binuclear Cu proteins exhibit different reactivities that correlate with their different electronic structures and exchange coupling interactions between the binuclear Cu centers. These studies provide insight into the role of exchange coupling between the Cu centers in their reaction mechanisms.

  3. Synthesis, spectroscopic and biological activities studies of acyclic and macrocyclic mono and binuclear metal complexes containing a hard-soft Schiff base

    NASA Astrophysics Data System (ADS)

    Abou-Hussein, Azza A. A.; Linert, Wolfgang

    Mono- and bi-nuclear acyclic and macrocyclic complexes with hard-soft Schiff base, H2L, ligand derived from the reaction of 4,6-diacetylresorcinol and thiocabohydrazide, in the molar ratio 1:2 have been prepared. The H2L ligand reacts with Co(II), Ni(II), Cu(II), Zn(II), Mn(II) and UO2(VI) nitrates, VO(IV) sulfate and Ru(III) chloride to get acyclic binuclear complexes except for VO(IV) and Ru(III) which gave acyclic mono-nuclear complexes. Reaction of the acyclic mono-nuclear VO(IV) and Ru(III) complexes with 4,6-diacetylresorcinol afforded the corresponding macrocyclic mono-nuclear VO(IV) and Ru(IIII) complexes. Template reactions of the 4,6-diacetylresorcinol and thiocarbohydrazide with either VO(IV) or Ru(III) salts afforded the macrocyclic binuclear VO(IV) and Ru(III) complexes. The Schiff base, H2L, ligand acts as dibasic with two NSO-tridentate sites and can coordinate with two metal ions to form binuclear complexes after the deprotonation of the hydrogen atoms of the phenolic groups in all the complexes, except in the case of the acyclic mononuclear Ru(III) and VO(IV) complexes, where the Schiff base behaves as neutral tetradentate chelate with N2S2 donor atoms. The ligands and the metal complexes were characterized by elemental analysis, IR, UV-vis 1H-NMR, thermal gravimetric analysis (TGA) and ESR, as well as the measurements of conductivity and magnetic moments at room temperature. Electronic spectra and magnetic moments of the complexes indicate the geometries of the metal centers are either tetrahedral, square planar or octahedral. Kinetic and thermodynamic parameters were calculated using Coats-Redfern equation, for the different thermal decomposition steps of the complexes. The ligands and the metal complexes were screened for their antimicrobial activity against Staphylococcus aureus as Gram-positive bacteria, and Pseudomonas fluorescens as Gram-negative bacteria in addition to Fusarium oxysporum fungus. Most of the complexes exhibit mild

  4. Anticancer activity assessment of two novel binuclear platinum (II) complexes.

    PubMed

    Shahsavani, Mohammad Bagher; Ahmadi, Shamseddin; Aseman, Marzieh Dadkhah; Nabavizadeh, S Masoud; Rashidi, Mehdi; Asadi, Zahra; Erfani, Nasrollah; Ghasemi, Atiyeh; Saboury, Ali Akbar; Niazi, Ali; Bahaoddini, Aminollah; Yousefi, Reza

    2016-08-01

    In the current study, two binuclear Pt (II) complexes, containing cis, cis-[Me2Pt (μ-NN) (μ-dppm) PtMe2] (1), and cis,cis-[Me2Pt(μ-NN)(μ dppm) Pt((CH2)4)] (2) in which NN=phthalazine and dppm=bis (diphenylphosphino) methane were evaluated for their anticancer activities and DNA/purine nucleotide binding properties. These Pt (II) complexes, with the non-classical structures, demonstrated a significant anticancer activity against Jurkat and MCF-7 cancer cell lines. The results of ethidium bromide/acridine orange staining and Caspase-III activity suggest that these complexes were capable to stimulate an apoptotic mechanism of cell death in the cancer cells. Using different biophysical techniques and docking simulation analysis, we indicated that these complexes were also capable to interact efficiently with DNA via a non-intercalative mechanism. According to our results, substitution of cyclopentane (in complex 2) with two methyl groups (in complex 1) results in significant improvement of the complex ability to interact with DNA and subsequently to induce the anticancer activity. Overall, these binuclear Pt (II) complexes are promising group of the non-classical potential anticancer agents which can be considered as molecular templates in designing of highly efficient platinum anticancer drugs. PMID:27289447

  5. Binuclear Rhodium(II) Complexes With Selective Antibacterial Activity.

    PubMed

    Bień, M; Lachowicz, T M; Rybka, A; Pruchnik, F P; Trynda, L

    1997-01-01

    Binuclear rhodium(II) complexes [Rh(2)Cl(2)(mu-OOCR)(2)(N-N)(2)] {R = H, Me; N-N = 2,2'-bipyridine (bpy), 1,10-phenanthroline (phen)} and [Rh(2)(mu-OOCR)(2)(N-N)(2)(H(2)O)(2)](RCOO)(2) (R = Me, Et;) have been synthesized and their structure and properties have been studied by electronic, IR and (1)H NMR spectroscopy. Antibacterial activity of these complexes against Escherichia coli and Staphylococcus aureus has been investigated. The most active antibacterial agents against E. coli were [Rh(2)Cl(2)(mu-OOCR)(2)(N-N)(2)] and [Rh(2)(mu-OOCR)(2)(N-N)(2)(H(2)O)(2)](RCOO)(2) {R = H and Me} which were considerably more active than the appropriate nitrogen ligands. The complexes show low activity against S. aureus. The activity of the complexes [Rh(2)(OOCR)(2)(N-N)(2)(H(2)O)(2)](OOCR)(2) against E. coli decreases in the series: R=H congruent withCH(3)>C(2)H(5)>C(3)H(7) congruent withC(4)H(9). The reverse order was found in the case of S. aureus. PMID:18475773

  6. Synthesis, characterization, biological activity of binuclear Co(II), Cu(II) and mononuclear Ni(II) complexes of bulky multi-dentate thiosemicarbazide

    NASA Astrophysics Data System (ADS)

    El-Gammal, O. A.; Abd Al-Gader, I. M.; El-Asmy, A. A.

    2014-07-01

    The chelation behavior of 9,10-dihydro-9,10-ethanoanthracene-11,12-dicarbonyl) bis (N-ethylhydrazine-1-carbothioamide) (H6ETS)(1) towards Co2+, Ni2+and Cu2+ have been studied. The spectral data revealed that the ligand acts as a bi- and/or mono-negative multi-dentate. The isolated Ni(II) and Cu(II) complexes are square-planar while the Co(II) is tetrahedral. EPR spectrum of Cu(II) complex confirmed simulated an axial spin-Hamiltonian exhibiting a four-line pattern with nitrogen super-hyperfine couplings originating from imine hydrazinic nitrogen atoms and possess a significant amount of tetrahedral distortion leading to a pseudo-square-planar geometry with unpaired electron has d ground state. Also, the thermal behavior and kinetic parameters were determined. Furthermore, the title compounds were investigated for their antibacterial activity using inhibition zone diameter and for DNA degradation, superoxide-scavenging activity as well as hydroxyl radicals that generated by the oxidation of cytochrome c in L-ascorbic acid/CuSO4-cytochrome c system.

  7. Binuclear Aromatic C-H Bond Activation at a Dirhenium Site.

    PubMed

    Adams, Richard D; Rassolov, Vitaly; Wong, Yuen Onn

    2016-01-22

    The electronically unsaturated dirhenium complex [Re2(CO)8(μ-H)(μ-Ph)] (1) has been found to exhibit aromatic C-H activation upon reaction with N,N-diethylaniline, naphthalene, and even [D6]benzene to yield the compounds [Re2(CO)8(μ-H)(μ-η(1)-NEt2C6H4)] (2), [Re2(CO)8(μ-H)(μ-η(2)-1,2-C10H7)] (3), and [D6]-1, respectively, in good yields. The mechanism has been elucidated by using DFT computational analyses, and involves a binuclear C-H bond-activation process. PMID:26643854

  8. Structure/function correlations over binuclear non-heme iron active sites.

    PubMed

    Solomon, Edward I; Park, Kiyoung

    2016-09-01

    Binuclear non-heme iron enzymes activate O2 to perform diverse chemistries. Three different structural mechanisms of O2 binding to a coupled binuclear iron site have been identified utilizing variable-temperature, variable-field magnetic circular dichroism spectroscopy (VTVH MCD). For the μ-OH-bridged Fe(II)2 site in hemerythrin, O2 binds terminally to a five-coordinate Fe(II) center as hydroperoxide with the proton deriving from the μ-OH bridge and the second electron transferring through the resulting μ-oxo superexchange pathway from the second coordinatively saturated Fe(II) center in a proton-coupled electron transfer process. For carboxylate-only-bridged Fe(II)2 sites, O2 binding as a bridged peroxide requires both Fe(II) centers to be coordinatively unsaturated and has good frontier orbital overlap with the two orthogonal O2 π* orbitals to form peroxo-bridged Fe(III)2 intermediates. Alternatively, carboxylate-only-bridged Fe(II)2 sites with only a single open coordination position on an Fe(II) enable the one-electron formation of Fe(III)-O2 (-) or Fe(III)-NO(-) species. Finally, for the peroxo-bridged Fe(III)2 intermediates, further activation is necessary for their reactivities in one-electron reduction and electrophilic aromatic substitution, and a strategy consistent with existing spectral data is discussed. PMID:27369780

  9. Activation of the binuclear metal center through formation of phosphotriesterase-inhibitor complexes.

    PubMed

    Samples, Cynthia R; Raushel, Frank M; DeRose, Victoria J

    2007-03-20

    Phosphotriesterase (PTE) from Pseudomonas diminuta is a binuclear metalloenzyme that catalyzes the hydrolysis of organophosphate nerve agents at rates approaching the diffusion-controlled limit. The proposed catalytic mechanism postulates the interaction of the substrate with the metal center and subsequent nucleophilic attack by the bridging hydroxide. X-band EPR spectroscopy was utilized to monitor the active site of Mn/Mn-substituted PTE upon addition of two inhibitors, diisopropyl methyl phosphonate and triethyl phosphate, and the product of hydrolysis, diethyl phosphate. The effects of inhibitor and product binding on the magnetic properties of the metal center and the hydroxyl bridge were evaluated by measuring changes in the features of the EPR spectra. The EPR spectra support the proposal that the binding of substrate analogues to the binuclear metal center diminishes the population of hydroxide-bridged species. These results, in conjunction with previously published kinetic and crystallographic data, suggest that substrate binding via the phosphoryl oxygen at the beta-metal weakens the coordination of the hydroxide bridge to the beta-metal. The weakened coordination to the beta-metal ion increases the nucleophilic character of the hydroxide and is coupled to the increase in the electrophilic character of the substrate. PMID:17315951

  10. Binuclear mercury(II) complexes of sulfonium ylides: Synthesis, structural characterization and anti-bacterial activity

    NASA Astrophysics Data System (ADS)

    Sabounchei, Seyyed Javad; Bagherjeri, Fateme Akhlaghi; Boskovic, Colette; Gable, Robert W.; Karamian, Roya; Asadbegy, Mostafa

    2013-02-01

    Reaction of α-keto stabilized sulfonium ylides (Me)2SCHC(O)C6H4R (R = p-Me (a); p-Cl (b)) with HgX2 (X = Cl, Br and I) in equimolar ratios using methanol as solvent leads to binuclear products of the type [HgX2(ylide)]2 (X = Cl (1), Br (2) and I (3)). Single crystal X-ray diffraction analysis reveals the presence of unexpected asymmetric halide-bridged dinuclear structures for 1a and 2b. Characterization of the compounds by IR, 1H- and 13C NMR spectroscopy confirmed coordination of the ylide to the metal through the carbon atom. In addition, the antibacterial effects of DMSO-solutions of the complexes were investigated by the disc diffusion method against three Gram positive and three negative bacteria. All complexes represent antibacterial activity against these bacteria with high levels of inhibitory potency exhibited against the Gram-positive species.

  11. Properties of Binuclear Rhodium(II) Complexes and Their Antibacterial Activity.

    PubMed

    Pruchnik, F P; Bień, M; Lachowicz, T

    1996-01-01

    Binuclear rhodium(II) complexes [Rh(2)Cl(2)(mu-OOCR)(2)(N-N)(2)], [Rh(2)(mu-OOCR)(2)(N-N)(2)(H(2)O)(2)](RCOO)(2) and [Rh(2)Cl(2)(mu-OOCCH(3))(terpy)(2)](H(3)O)Cl(2).9H(2)O (R = H, Me, Bu(n), ph, PhCHOH; N-N = 2,2'-bipyridine (bpy), 1,10-phenanthroline (phen), 2,9-dimethyl-1,10-phenanthroline (dmp) and 6,7-dimethyl-2,3- di(2-pyridyl)quinoxaline (dmpq); terpy 2,2':6',2''-terpyridine) have been synthesized and their structure and properties have been studied by electronic, IR and (1)H NMR spectroscopy. Antibacterial activity of these complexes against Staphylococcus aureus and Escherichia coli has been investigated. The most active antibacterial agents against S. aureus were [Rh(2)(OOCPh)(2)(phen)(2)(H(2)O)(2)](2+), [Rh(2)(OOCPh)(2)(dmpq)(2)(H(2)O)(2)](2+), [Rh(2)(OOCBu)(2)(phen)(2)(H(2)O)(2)](2+) and [Rh(2)-(OOCBu)(2)(bpy)(2)(H(2)O)(2)](2+) which were considerably more active than the appropriate nitrogen ligands. The complexes show rather low activity against E. coli. PMID:18475754

  12. Synthesis, characterization and biological studies of homo and hetero-binuclear 13-membered pentaaza bis (macrocyclic) complexes

    NASA Astrophysics Data System (ADS)

    Zafar, Hina; Kareem, Abdul; Sherwani, Asif; Mohammad, Owais; Khan, Tahir Ali

    2015-01-01

    A new series of homo and hetero binuclear 13-membered pentaaza bis (macrocyclic) complexes, [MM‧LX4], [M = Cu(II), M‧ = Cu(II), Co(II), Ni(II) and Sn(II); L = ligand and X = Cl or NO3] have been synthesized by the template reaction of dichloro/dinitrato diphenyl sulphone 1,3,6,9,12-tetra hydro pentaazacyclo pantane copper (II) complexes with formaldehyde, triethylenetetraamine, and respective metal salts in 1:2:1:1 molar ratio. The complexes have been characterized by elemental analyses, molar conductance measurements, ESI-mass, 1H, 13C and 119Sn NMR, IR, electronic and EPR spectral studies. The results of elemental analyses, ESI-mass and conductivity measurements confirmed the stoichiometry of the complexes while the characteristic absorption bands and resonance peaks in IR and NMR spectra confirmed the formation of macrocyclic frameworks of the complexes. These studies showed octahedral geometry around the metal ion. The thermal stability of copper complexes was also studied by TGA and DTA analyses. Some complexes of this series were also studied for their in vitro anticancer activity against cancer cells lines: Hep3B, MCF7, and HeLa. The recorded IC50 values for the tested complexes show moderate to good cytotoxicity against these cancer cell lines.

  13. Structural, spectral and biological studies of binuclear tetradentate metal complexes of N 3O Schiff base ligand synthesized from 4,6-diacetylresorcinol and diethylenetriamine

    NASA Astrophysics Data System (ADS)

    Emara, Adel A. A.

    2010-09-01

    The binuclear Schiff base, H 2L, ligand was synthesized by reaction of 4,6-diacetylresorcinol with diethylenetriamine in the molar ratio 1:2. The coordination behavior of the H 2L towards Cu(II), Ni(II), Co(II), Zn(II), Fe(III), Cr(III), VO(IV) and UO 2(VI) ions has been investigated. The elemental analyses, magnetic moments, thermal studies and IR, electronic, 1H NMR, ESR and mass spectra were used to characterize the isolated ligand and its metal complexes. The ligand acts as dibasic with two N 3O-tetradentate sites and can coordinate with two metal ions to form binuclear complexes. The bonding sites are the nitrogen atoms of the azomethine and amine groups and the oxygen atoms of the phenolic groups. The metal complexes exhibit either square planar, tetrahedral, square pyramid or octahedral structures. The Schiff base ligand and its metal complexes were tested against four pathogenic bacteria ( Staphylococcus aureus and Streptococcus pyogenes) as Gram-positive bacteria, and ( Pseudomonas fluorescens and Pseudomonas phaseolicola) as Gram-negative bacteria and two pathogenic fungi ( Fusarium oxysporum and Aspergillus fumigatus) to assess their antimicrobial properties. Most of the complexes exhibit mild antibacterial and antifungal activities against these organisms.

  14. DNA Cleavage and Condensation Activities of Mono- and Binuclear Hybrid Complexes and Regulation by Graphene Oxide.

    PubMed

    Li, Shuo; Dai, Mingxing; Zhang, Chunping; Jiang, Bingying; Xu, Junqiang; Zhou, Dewen; Gu, Zhongwei

    2016-01-01

    Hybrid complexes with N,N'-bis(2-benzimidazolylmethyl)amine and cyclen moieties are novel enzyme mimics and controlled DNA release materials, which could interact with DNA through three models under different conditions. In this paper, the interactions between plasmid DNA and seven different complexes were investigated, and the methods to change the interaction patterns by graphene oxide (GO) or concentrations were also investigated. The cleavage of pUC19 DNA promoted by target complexes were via hydrolytic or oxidative mechanisms at low concentrations ranging from 3.13 × 10(-7) to 6.25 × 10(-5) mol/L. Dinuclear complexes 2a and 2b can promote the cleavage of plasmid pUC19 DNA to a linear form at pH values below 7.0. Furthermore, binuclear hybrid complexes could condense DNA as nanoparticles above 3.13 × 10(-5) mol/L and partly release DNA by graphene oxide with π-π stacking. Meanwhile, the results also reflected that graphene oxide could prevent DNA from breaking down. Cell viability assays showed dinuclear complexes were safe to normal human hepatic cells at relative high concentrations. The present work might help to develop novel strategies for the design and synthesis of DNA controllable releasing agents, which may be applied to gene delivery and also to exploit the new application for GO. PMID:27428945

  15. [Mono- and Binuclear Dinitrosyl Iron Complexes with Thiol-containing Ligands in Various Biosystems].

    PubMed

    Vanin, A F; Mikoyan, V D; Kubrina, L N; Borodulin, R R; Burgova, E N

    2015-01-01

    It has been shown that dinitrosyl iron complexes with thiol-containing ligands, bound with modified bovine serum albumin with high amount of thiol groups, appeared in baker yeast or in animal tissues in the presence of exogenous or endogenous nitric oxide, respectively, are represented predominantly by EPR-silent binuclear form. This form can be transformed into EPR-active mononuclear form of dinitrosyl iron complexes with an increase in pH to basic values, into EPR-active form of mononuclear iron nitrosyl complexes in case of bielectronic recovery of the binuclear form of dinitrosyl iron complexes or under the action of dithiocarbamate derivatives. The latter induced the transformation of dinitrosyl iron complexes into EPR-active mononitrosyl iron complexes with dithiocarbamates. A significant amount of binuclear dinitrosyl iron complexes with thiol-containing ligands in living systems and identical biological activity of these complexes and endogenous nitric oxide systems allow of considering endogenous binuclear dinitrosyl iron complexes as a "working form" of endogenous nitric oxide recognized now as a universal regulator of biological processes. PMID:26394474

  16. Enhanced activity and stability of binuclear iron (III) phthalocyanine on graphene nanosheets for electrocatalytic oxygen reduction in acid

    NASA Astrophysics Data System (ADS)

    Li, Tengfei; Peng, Yingxiang; Li, Kai; Zhang, Rui; Zheng, Lirong; Xia, Dingguo; Zuo, Xia

    2015-10-01

    Binuclear iron (III) phthalocyanine (bi-FePc) and iron (III) phthalocyanine (FePc) are synthesized in situ on graphene nanosheets (GNS) by a microwave-assisted method. TEM, ultraviolet-visible spectroscopy and Raman spectroscopy confirm that bi-FePc is supported on GNS through π-π interactions. The catalytic activity of the bi-FePc/GNS and FePc/GNS composites in the oxygen reduction reaction (ORR) is investigated by CV and RDE measurements. The bi-FePc/GNS composite shows a more positive onset potential (0.12 V vs. Hg/Hg2SO4) for the ORR than FePc/GNS (-0.02 V vs. Hg/Hg2SO4), and a four-electron mechanism similar to commercial Pt/C (0.22 V vs. Hg/Hg2SO4). Moreover, bi-FePc/GNS exhibits good stability with 100% retention after 36,000 s, while Pt/C has a retention of only 50% after the same period. Additionally, bi-FePc/GNS shows higher tolerance toward methanol than the Pt/C catalyst. XPS and X-ray absorption fine structure spectroscopy demonstrate that compared with FePc/GNS, bi-FePc/GNS possesses a higher concentration of Fe3+ and smaller skeleton radius of the phthalocyanine ring, which has a square-planar structure that evidently favors the ORR. Thus, bi-FePc/GNS is a promising candidate as a cathode catalyst in direct methanol fuel cells.

  17. Synthesis, spectroscopic characterization, electrochemistry and biological evaluation of some binuclear transition metal complexes of bicompartmental ONO donor ligands containing benzo[b]thiophene moiety

    NASA Astrophysics Data System (ADS)

    Mahendra Raj, K.; Vivekanand, B.; Nagesh, G. Y.; Mruthyunjayaswamy, B. H. M.

    2014-02-01

    A series of new binucleating Cu(II), Co(II), Ni(II) and Zn(II) complexes of bicompartmental ligands with ONO donor were synthesized. The ligands were obtained by the condensation of 3-chloro-6-substituted benzo[b]thiophene-2-carbohydrazides and 4,6-diacetylresorcinol. The synthesized ligands and their complexes were characterized by elemental analysis and various spectroscopic techniques. Elemental analysis, IR, 1H NMR, ESI-mass, UV-Visible, TG-DTA, magnetic measurements, molar conductance and powder-XRD data has been used to elucidate their structures. The bonding sites are the oxygen atom of amide carbonyl, azomethine nitrogen and phenolic oxygen for ligands 1 and 2. The binuclear nature of the complexes was confirmed by ESR spectral data. TG-DTA studies for some complexes showed the presence of coordinated water molecules and the final product is the metal oxide. All the complexes were investigated for their electrochemical activity, only the Cu(II) complexes showed the redox property. Cu(II) complexes were square planar, whereas Co(II), Ni(II) and Zn(II) complexes were octahedral. Powder-XRD pattern have been studied in order to test the degree of crystallinity of the complexes and unit cell calculations were made. In order to evaluate the effect of antimicrobial activity of metal ions upon chelation, both the ligands and their metal complexes were screened for their antibacterial and antifungal activities by minimum inhibitory concentration (MIC) method. The results showed that the metal complexes were found to be more active than free ligands. The DNA cleaving capacities of all the complexes were analyzed by agarose gel electrophoresis method against supercoiled plasmid DNA. Among the compounds tested for antioxidant capacity, ligand 1 displayed excellent activity than its metal complexes.

  18. A series of binuclear lanthanide(III) complexes: Crystallography, antimicrobial activity and thermochemistry properties studies

    NASA Astrophysics Data System (ADS)

    Zhang, Ying-Ying; Ren, Ning; Xu, Su-Ling; Zhang, Jian-Jun; Zhang, Da-Hai

    2015-02-01

    A series of novel lanthanide complexes with the general formula [Ln(3,4-DClBA)3phen]2 (Ln = Ho(1), Nd(2), Sm(3), Dy(4), Eu(5), Tb(6), Yb(7) and Er(8), 3,4-DClBA = 3,4-dichlorobenzoate, phen = 1,10-phenanthroline) were prepared at room temperature and characterized. The crystal structures of complexes 1-8 have been determined by single crystal X-ray diffraction. These complexes are isomorphous and lanthanide ions are all eight-coordinated to oxygen atoms and nitrogen atoms with distorted square-antiprism geometry. The thermal decomposition mechanism and TG-FTIR spectra of gaseous products of thermal decomposition processes for complexes 1-8 were acquired through TG/DSC-FTIR system. The heat capacities of complexes 1-8 were measured using DSC technology and fitted to a polynomial equation by the least-squares method. Complexes 3-6 display characteristic lanthanide emission bands in the visible region. Meanwhile, these complexes exhibit in good antimicrobial activity against Candida albicans, Escherichia coli, and Staphylococcus aureu.

  19. Synthesis, spectroscopic characterization and antimicrobial activity of binuclear metal complexes of a new asymmetrical Schiff base ligand: DNA binding affinity of copper(II) complexes

    NASA Astrophysics Data System (ADS)

    Shebl, Magdy

    2014-01-01

    The 1:1 condensation of o-acetoacetylphenol and 1,2-diaminopropane under condition of high dilution gives the mono-condensed Schiff base, (E)-3-(1-aminopropan-2-ylimino)-1-(2-hydroxyphenyl)butan-1-one. The mono-condensed Schiff base has been used for further condensation with isatin to obtain the new asymmetrical dicompartmental Schiff base ligand, (E)-3-(2-((E)-4-(2-hydroxyphenyl)-4-oxobutan-2-ylideneamino) propylimino)indolin-2-one (H3L) with a N2O3 donor set. Reactions of the ligand with metal salts give a series of new binuclear complexes. The ligand and its metal complexes were characterized by elemental analyses, IR, 1H and 13C NMR, electronic, ESR and mass spectra, conductivity and magnetic susceptibility measurements as well as thermal analyses. The analytical and spectroscopic tools showed that the complexes can be formulated as: [(HL)(VO)2(SO4)(H2O)]·4H2O, [(HL)Fe2Cl4(H2O)3]·EtOH, [(HL)Fe2(ox)Cl2(H2O)3]·2H2O, [(L)M2(OAc)(H2O)m]·nH2O; M = Co, Ni or Cu, m = 4, 0 and n = 2, 3, [(HL)Cu2Cl]Cl·6H2O and [(L)(UO2)2(OAc)(H2O)3]·6H2O. The metal complexes exhibited octahedral geometrical arrangements except copper complexes that exhibited tetrahedral geometries and uranyl complex in which the metal ion is octa-coordinated. The Schiff base and its metal complexes were evaluated for antimicrobial activity against Gram positive bacteria (Staphylococcus aureus), Gram negative bacteria (Escherichia coli) and fungi (Candida albicans and Aspergillus flavus). The ligand and some of its complexes were found to be biologically active. The DNA-binding properties of the copper complexes (6 and 7) have been investigated by electronic absorption, fluorescence and viscosity measurements. The results obtained indicate that these complexes bind to DNA via an intercalation binding mode with an intrinsic binding constant, Kb of 1.34 × 104 and 2.5 × 104 M-1, respectively.

  20. Synthesis, characterization, biological evaluation and docking studies of macrocyclic binuclear manganese(II) complexes containing 3,5-dinitrobenzoyl pendant arms

    NASA Astrophysics Data System (ADS)

    Arthi, P.; Shobana, S.; Srinivasan, P.; Mitu, L.; Kalilur Rahiman, A.

    2015-05-01

    A series of bis(phenoxo) bridged binuclear manganese(II) complexes of the type [Mn2L1-3](ClO4)2 (1-3) containing 3,5-dinitrobenzoyl pendant-arms have been synthesized by cyclocondensation of 2,6-diformyl-4-R-phenols (where R = sbnd CH3, sbnd C(CH3)3 or sbnd Br) with 2,2‧-3,5-dinitrobenzoyliminodi(ethylamine) trihydrochloride in the presence of manganese(II) perchlorate. The IR spectra of complexes indicate the presence of uncoordinated perchlorate anions. The UV-Vis spectra of complexes suggest the distorted octahedral geometry around manganese(II) nuclei. The EPR spectra of Mn(II) complexes show a broad signal with g value 2.03-2.04, which is characteristic for octahedral high spin Mn2+ complex. The observed room temperature magnetic moment values of the Mn(II) complexes (5.60-5.62 B.M.) are less than the normal value (5.92 B.M.), indicating weak antiferromagnetic coupling interaction between the two metal ions. Electrochemical studies of the complexes show two distinct quasi-reversible one electron transfer processes in the cathodic (E1pc = -0.73 to -0.76 V, E2pc = -1.30 to -1.36 V), and anodic (E1pa = 1.02-1.11 V, E2pa = 1.32-1.79 V) potential regions. Antibacterial efficacy of complexes have been screened against four Gram (-ve) and two Gram (+ve) bacterial strains. The DNA interaction studies suggest that these complexes bind with CT-DNA by intercalation, giving the binding affinity in the order 1 > 2 > 3. All the complexes display significant cleavage activity against circular plasmid pBR322 DNA. Docking simulation was performed to insert complexes into the crystal structure of EGFR tyrosine kinase and B-DNA at active site to determine the probable binding mode.

  1. Metadata Activities in Biology

    SciTech Connect

    Inigo, Gil San; HUTCHISON, VIVIAN; Frame, Mike; Palanisamy, Giri

    2010-01-01

    The National Biological Information Infrastructure program has advanced the biological sciences ability to standardize, share, integrate and synthesize data by making the metadata program a core of its activities. Through strategic partnerships, a series of crosswalks for the main biological metadata specifications have enabled data providers and international clearinghouses to aggregate and disseminate tens of thousands of metadata sets describing petabytes of data records. New efforts at the National Biological Information Infrastructure are focusing on better metadata creation and curation tools, semantic mediation for data discovery and other curious initiatives.

  2. Mono- and binuclear copper(II) complexes of new hydrazone ligands derived from 4,6-diacetylresorcinol: Synthesis, spectral studies and antimicrobial activity

    NASA Astrophysics Data System (ADS)

    Shebl, Magdy; El-ghamry, Mosad A.; Khalil, Saied M. E.; Kishk, Mona A. A.

    Two new hydrazone ligands, H2L1 and H2L2, were synthesized by the condensation of 4,6-diacetylresorcinol with 3-hydrazino-5,6-diphenyl-1,2,4-triazine and isatin monohydrazone, respectively. The structures of the ligands were elucidated by elemental analyses, IR, 1H NMR, electronic and mass spectra. Reactions of the ligands with several copper(II) salts, including AcO-, NO3-, SO42-, Cl- and Br- afforded mono- and binuclear metal complexes. Also, the ligands were allowed to react with Cu(II) ion in the presence of a secondary ligand (L‧) [N,O-donor; 8-hydroxyquinoline, N,N-donor; 1,10-phenanthroline or O,O-donor; benzoylacetone]. Characterization and structure elucidation of the prepared complexes were achieved by elemental and thermal analyses, IR, electronic, mass and ESR spectra as well as conductivity and magnetic susceptibility measurements. The ESR spin Hamiltonian parameters of some complexes were calculated. The spectroscopic data showed that the H2L1 ligand acts as a neutral or monobasic tridentate ligand while the H2L2 ligand acts as a bis(monobasic tridentate) ligand. The coordination sites with the copper(II) ion are phenolic oxygen, azomethine nitrogen and triazinic nitrogen (H2L1 ligand) or isatinic oxygen (H2L2 ligand). The metal complexes exhibited octahedral and square planar geometrical arrangements depending on the nature of the anion. The ligands and some metal complexes showed antimicrobial activity.

  3. Binuclear cobalt(II), nickel(II), copper(II) and palladium(II) complexes of a new Schiff-base as ligand: Synthesis, structural characterization, and antibacterial activity

    NASA Astrophysics Data System (ADS)

    Geeta, B.; Shravankumar, K.; Reddy, P. Muralidhar; Ravikrishna, E.; Sarangapani, M.; Reddy, K. Krishna; Ravinder, V.

    2010-11-01

    A binucleating new Schiff-base ligand with a phenylene spacer, afforded by the condensation of glycyl-glycine and o-phthalaldehyde has been served as an octadentate N 4O 4 ligand in designing some binuclear complexes of cobalt(II), nickel(II), copper(II), and palladium(II). The binding manner of the ligand to the metal and the composition and geometry of the metal complexes were examined by elemental analysis, conductivity measurements, magnetic moments, IR, 1H, 13C NMR, ESR and electronic spectroscopies, and TGA measurements. There are two different coordination/chelation environments present around two metal centers of each binuclear complex. The composition of the complexes in the coordination sphere was found to be [M 2(L)(H 2O) 4] (where M = Co(II) and Ni(II)) and [M 2(L)] (where M = Cu(II) and Pd(II)). In the case of Cu(II) complexes, ESR spectra provided further information to confirm the binuclear structure and the presence of magnetic interactions. All the above metal complexes have shown moderate to good antibacterial activity against Gram-positive and Gram-negative bacteria.

  4. Reactivity of the binuclear non-heme iron active site of Δ⁹ desaturase studied by large-scale multireference ab initio calculations.

    PubMed

    Chalupský, Jakub; Rokob, Tibor András; Kurashige, Yuki; Yanai, Takeshi; Solomon, Edward I; Rulíšek, Lubomír; Srnec, Martin

    2014-11-12

    The results of density matrix renormalization group complete active space self-consistent field (DMRG-CASSCF) and second-order perturbation theory (DMRG-CASPT2) calculations are presented on various structural alternatives for the O-O and first C-H activating step of the catalytic cycle of the binuclear nonheme iron enzyme Δ(9) desaturase. This enzyme is capable of inserting a double bond into an alkyl chain by double hydrogen (H) atom abstraction using molecular O2. The reaction step studied here is presumably associated with the highest activation barrier along the full pathway; therefore, its quantitative assessment is of key importance to the understanding of the catalysis. The DMRG approach allows unprecedentedly large active spaces for the explicit correlation of electrons in the large part of the chemically important valence space, which is apparently conditio sine qua non for obtaining well-converged reaction energetics. The derived reaction mechanism involves protonation of the previously characterized 1,2-μ peroxy Fe(III)Fe(III) (P) intermediate to a 1,1-μ hydroperoxy species, which abstracts an H atom from the C10 site of the substrate. An Fe(IV)-oxo unit is generated concomitantly, supposedly capable of the second H atom abstraction from C9. In addition, several popular DFT functionals were compared to the computed DMRG-CASPT2 data. Notably, many of these show a preference for heterolytic C-H cleavage, erroneously predicting substrate hydroxylation. This study shows that, despite its limitations, DMRG-CASPT2 is a significant methodological advancement toward the accurate computational treatment of complex bioinorganic systems, such as those with the highly open-shell diiron active sites. PMID:25313991

  5. Crystal Structure of Phosphatidylglycerophosphatase (PGPase), a Putative Membrane-Bound Lipid Phosphatase, Reveals a Novel Binuclear Metal Binding Site and Two Proton Wires

    SciTech Connect

    Kumaran,D.; Bonnano, J.; Burley, S.; Swaminathan, S.

    2006-01-01

    Phosphatidylglycerophosphatase (PGPase), an enzyme involved in lipid metabolism, catalyzes formation of phosphatidylglycerol from phosphatidylglycerophosphate. Phosphatidylglycerol is a multifunctional phospholipid, found in the biological membranes of many organisms. Here, we report the crystal structure of Listeria monocytogenes PGPase at 1.8 Angstroms resolution. PGPase, an all-helical molecule, forms a homotetramer. Each protomer contains an independent active site with two metal ions, Ca{sup 2+} and Mg{sup 2+}, forming a hetero-binuclear center located in a hydrophilic cavity near the surface of the molecule. The binuclear center, conserved ligands, metal-bound water molecules, and an Asp-His dyad form the active site. The catalytic mechanism of this enzyme is likely to proceed via binuclear metal activated nucleophilic water. The binuclear metal-binding active-site environment of this structure should provide insights into substrate binding and metal-dependent catalysis. A long channel with inter-linked linear water chains, termed 'proton wires', is observed at the tetramer interface. Comparison of similar water chain structures in photosynthetic reaction centers (RCs), Cytochrome f, gramicidin, and bacteriorhodopsin, suggests that PGPase may conduct protons via proton wires.

  6. Synthesis, spectroscopic studies, molecular modeling and antimicrobial activity of binuclear Co(II) and Cu(II) complexes of 4,6-diacetylresorcinol

    NASA Astrophysics Data System (ADS)

    Shebl, Magdy; Khalil, Saied M. E.; Taha, A.; Mahdi, M. A. N.

    2013-09-01

    Reactions of 4,6-diacetylresorcinol with different cobalt(II) and copper(II) salts viz., OAc-, Cl-, NO3- and SO42-, yielded a new series of binuclear metal complexes. Reactions of the ligand with these metal ions in the presence of a secondary ligand (L‧) [O,O-donor; acetylacetone, N,O-donor; 8-hydroxyquinoline or N,N-donor; 1,10-phenanthroline and N,N,N‧,N‧-tetramethylethylenediamine] in 1:2:2 (L:M:L‧) molar ratio yielded mixed-ligand complexes with different molar ratios. The metal complexes were characterized by elemental and thermal analyses, IR, electronic, ESR and mass spectra as well as conductivity and magnetic susceptibility measurements. The analytical and spectroscopic data suggested that the H2L ligand behaves as a neutral, monobasic or dibasic tetradentate ligand, depending on the type of the anion and secondary ligand used, through the two phenolic and two carbonyl groups. Electronic spectra, magnetic and conductivity measurements showed that all complexes are octahedral with non-electrolytic nature. The profile of ESR spectra of copper(II) complexes suggested the octahedral geometry and the spin Hamiltonian parameters of the complexes were calculated and discussed. Molecular orbital calculations were performed for metal complexes using Hyperchem 7.52 program on the bases of PM3 level and the results correlated with the experimental data. The free ligand and some of its metal complexes showed antimicrobial activity towards some of Gram-positive and Gram-negative bacteria, yeast (Candida albicans) and fungus (Aspergillus fumigatus).

  7. Synthesis, spectroscopic studies, molecular modeling and antimicrobial activity of binuclear Co(II) and Cu(II) complexes of 4,6-diacetylresorcinol.

    PubMed

    Shebl, Magdy; Khalil, Saied M E; Taha, A; Mahdi, M A N

    2013-09-01

    Reactions of 4,6-diacetylresorcinol with different cobalt(II) and copper(II) salts viz., OAc(-), Cl(-), NO3(-) and SO4(2-), yielded a new series of binuclear metal complexes. Reactions of the ligand with these metal ions in the presence of a secondary ligand (L') [O,O-donor; acetylacetone, N,O-donor; 8-hydroxyquinoline or N,N-donor; 1,10-phenanthroline and N,N,N',N'-tetramethylethylenediamine] in 1:2:2 (L:M:L') molar ratio yielded mixed-ligand complexes with different molar ratios. The metal complexes were characterized by elemental and thermal analyses, IR, electronic, ESR and mass spectra as well as conductivity and magnetic susceptibility measurements. The analytical and spectroscopic data suggested that the H2L ligand behaves as a neutral, monobasic or dibasic tetradentate ligand, depending on the type of the anion and secondary ligand used, through the two phenolic and two carbonyl groups. Electronic spectra, magnetic and conductivity measurements showed that all complexes are octahedral with non-electrolytic nature. The profile of ESR spectra of copper(II) complexes suggested the octahedral geometry and the spin Hamiltonian parameters of the complexes were calculated and discussed. Molecular orbital calculations were performed for metal complexes using Hyperchem 7.52 program on the bases of PM3 level and the results correlated with the experimental data. The free ligand and some of its metal complexes showed antimicrobial activity towards some of Gram-positive and Gram-negative bacteria, yeast (Candida albicans) and fungus (Aspergillus fumigatus). PMID:23743042

  8. A binuclear complex constituted by diethyldithiocarbamate and copper(I) functions as a proteasome activity inhibitor in pancreatic cancer cultures and xenografts

    SciTech Connect

    Han, Jinbin; Yue, Xiaoqiang; Chang, Jinjia; Shi, Weidong; Hua, Yongqiang

    2013-12-15

    It is a therapeutic strategy for cancers including pancreatic to inhibit proteasome activity. Disulfiram (DSF) may bind copper (Cu) to form a DSF–Cu complex. DSF–Cu is capable of inducing apoptosis in cancer cells by inhibiting proteasome activity. DSF is rapidly converted to diethyldithiocarbamate (DDTC) within bodies. Copper(II) absorbed by bodies is reduced to copper(I) when it enters cells. We found that DDTC and copper(I) could form a binuclear complex which might be entitled DDTC–Cu(I), and it had been synthesized by us in the laboratory. This study is to investigate the anticancer potential of this complex on pancreatic cancer and the possible mechanism. Pancreatic cancer cell lines, SW1990, PANC-1 and BXPC-3 were used for in vitro assays. Female athymic nude mice grown SW1990 xenografts were used as animal models. Cell counting kit-8 (cck-8) assay and flow cytometry were used for analyzing apoptosis in cells. A 20S proteasome assay kit was used in proteasome activity analysis. Western blot (WB) and immunohistochemistry (IHC) and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assays were used in tumor sample analysis. The results suggest that DDTC–Cu(I) inhibit pancreatic cancer cell proliferation and proteasome activity in vitro and in vivo. Accumulation of ubiquitinated proteins, and increased p27 as well as decreased NF-κB expression were detected in tumor tissues of DDTC–Cu(I)-treated group. Our data indicates that DDTC–Cu(I) is an effective proteasome activity inhibitor with the potential to be explored as a drug for pancreatic cancer. - Highlights: • A new structure of DDTC–Cu(I) was reported for the first time. • DDTC–Cu(I) dissolved directly in water was for in vitro and in vivo uses. • DDTC–Cu(I) demonstrated significant anticancer effect in vitro and in vivo. • DDTC–Cu(I) is capable of inhibiting proteasome activity in vitro and in vivo.

  9. Spectroscopic Definition of the Ferroxidase Site in M Ferritin: Comparison of Binuclear Substrate vs. Cofactor Active Sites

    PubMed Central

    Schwartz, Jennifer K.; Liu, Xiaofeng S.; Tosha, Takehiko; Theil, Elizabeth C.; Solomon, Edward I.

    2008-01-01

    Maxi ferritins, 24 subunit protein nanocages, are essential in humans, plants, bacteria, and other animals for the concentration and storage of iron as hydrated ferric oxide, while minimizing free radical generation or use by pathogens. Formation of the precursors to these ferric oxides is catalyzed at a non-heme biferrous substrate site, which has some parallels with the cofactor sites in other biferrous enzymes. A combination of circular dichroism (CD), magnetic circular dichroism (MCD), and variable-temperature, variable-field MCD (VTVH MCD) has been used to probe Fe(II) binding to the substrate active site in frog M ferritin. These data determined that the active site within each subunit consists of two inequivalent five-coordinate (5C) ferrous centers that are weakly anti-ferromagnetically coupled, consistent with a μ-1,3 carboxylate bridge. The active site ligand set is unusual and likely includes a terminal water bound to each Fe(II) center. The Fe(II) ions bind to the active sites in a concerted manner, and cooperativity among the sites in each subunit is observed, potentially providing a mechanism for the control of ferritin iron loading. Differences in geometric and electronic structure – including a weak ligand field, availability of two water ligands at the biferrous substrate site, and the single carboxylate bridge in ferritin – coincide with the divergent reaction pathways observed between this substrate site and the previously studied cofactor active sites. PMID:18576633

  10. Structural Diversity Within the Mononuclear and Binuclear Active Sites of N-Acetyl-D-Glucosamine-6-Phosphate Deacetylase

    SciTech Connect

    Hall,R.; Brown, S.; Fedorov, A.; Fedorov, E.; Xu, C.; Babbitt, P.; Almo, S.; Raushel, F.

    2007-01-01

    NagA catalyzes the hydrolysis of N-acetyl-D-glucosamine-6-phosphate to D-glucosamine-6-phosphate and acetate. X-ray crystal structures of NagA from Escherichia coli were determined to establish the number and ligation scheme for the binding of zinc to the active site and to elucidate the molecular interactions between the protein and substrate. The three-dimensional structures of the apo-NagA, Zn-NagA, and the D273N mutant enzyme in the presence of a tight-binding N-methylhydroxyphosphinyl-D-glucosamine-6-phosphate inhibitor were determined. The structure of the Zn-NagA confirms that this enzyme binds a single divalent cation at the beta-position in the active site via ligation to Glu-131, His-195, and His-216. A water molecule completes the ligation shell, which is also in position to be hydrogen bonded to Asp-273. In the structure of NagA bound to the tight binding inhibitor that mimics the tetrahedral intermediate, the methyl phosphonate moiety has displaced the hydrolytic water molecule and is directly coordinated to the zinc within the active site. The side chain of Asp-273 is positioned to activate the hydrolytic water molecule via general base catalysis and to deliver this proton to the amino group upon cleavage of the amide bond of the substrate. His-143 is positioned to help polarize the carbonyl group of the substrate in conjunction with Lewis acid catalysis by the bound zinc. The inhibitor is bound in the {alpha}-configuration at the anomeric carbon through a hydrogen bonding interaction of the hydroxyl group at C-1 with the side chain of His-251. The phosphate group of the inhibitor attached to the hydroxyl at C-6 is ion paired with Arg-227 from the adjacent subunit. NagA from Thermotoga maritima was shown to require a single divalent cation for full catalytic activity.

  11. Structural diversity within the mononuclear and binuclear active sites of N-acetyl-D-glucosamine-6-phosphate deacetylase.

    PubMed

    Hall, Richard S; Brown, Shoshana; Fedorov, Alexander A; Fedorov, Elena V; Xu, Chengfu; Babbitt, Patricia C; Almo, Steven C; Raushel, Frank M

    2007-07-10

    NagA catalyzes the hydrolysis of N-acetyl-d-glucosamine-6-phosphate to d-glucosamine-6-phosphate and acetate. X-ray crystal structures of NagA from Escherichia coli were determined to establish the number and ligation scheme for the binding of zinc to the active site and to elucidate the molecular interactions between the protein and substrate. The three-dimensional structures of the apo-NagA, Zn-NagA, and the D273N mutant enzyme in the presence of a tight-binding N-methylhydroxyphosphinyl-d-glucosamine-6-phosphate inhibitor were determined. The structure of the Zn-NagA confirms that this enzyme binds a single divalent cation at the beta-position in the active site via ligation to Glu-131, His-195, and His-216. A water molecule completes the ligation shell, which is also in position to be hydrogen bonded to Asp-273. In the structure of NagA bound to the tight binding inhibitor that mimics the tetrahedral intermediate, the methyl phosphonate moiety has displaced the hydrolytic water molecule and is directly coordinated to the zinc within the active site. The side chain of Asp-273 is positioned to activate the hydrolytic water molecule via general base catalysis and to deliver this proton to the amino group upon cleavage of the amide bond of the substrate. His-143 is positioned to help polarize the carbonyl group of the substrate in conjunction with Lewis acid catalysis by the bound zinc. The inhibitor is bound in the alpha-configuration at the anomeric carbon through a hydrogen bonding interaction of the hydroxyl group at C-1 with the side chain of His-251. The phosphate group of the inhibitor attached to the hydroxyl at C-6 is ion paired with Arg-227 from the adjacent subunit. NagA from Thermotoga maritima was shown to require a single divalent cation for full catalytic activity. PMID:17567048

  12. Active Biological Materials

    PubMed Central

    Fletcher, Daniel A.; Geissler, Phillip L.

    2011-01-01

    Cells make use of dynamic internal structures to control shape and create movement. By consuming energy to assemble into highly organized systems of interacting parts, these structures can generate force and resist compression, as well as adaptively change in response to their environment. Recent progress in reconstituting cytoskeletal structures in vitro has provided an opportunity to characterize the mechanics and dynamics of filament networks formed from purified proteins. Results indicate that a complex interplay between length scales and timescales underlies the mechanical responses of these systems and that energy consumption, as manifested in molecular motor activity and cytoskeletal filament growth, can drive transitions between distinct material states. This review discusses the basic characteristics of these active biological materials that set them apart from conventional materials and that create a rich array of unique behaviors. PMID:18999991

  13. Binuclear metallohydrolases: complex mechanistic strategies for a simple chemical reaction.

    PubMed

    Schenk, Gerhard; Mitić, Nataša; Gahan, Lawrence R; Ollis, David L; McGeary, Ross P; Guddat, Luke W

    2012-09-18

    Binuclear metallohydrolases are a large family of enzymes that require two closely spaced transition metal ions to carry out a plethora of hydrolytic reactions. Representatives include purple acid phosphatases (PAPs), enzymes that play a role in bone metabolism and are the only member of this family with a heterovalent binuclear center in the active form (Fe(3+)-M(2+), M = Fe, Zn, Mn). Other members of this family are urease, which contains a di-Ni(2+) center and catalyzes the breakdown of urea, arginase, which contains a di-Mn(2+) center and catalyzes the final step in the urea cycle, and the metallo-β-lactamases, which contain a di-Zn(2+) center and are virulence factors contributing to the spread of antibiotic-resistant pathogens. Binuclear metallohydrolases catalyze numerous vital reactions and are potential targets of drugs against a wide variety of human disorders including osteoporosis, various cancers, antibiotic resistance, and erectile dysfunctions. These enzymes also tend to catalyze more than one reaction. An example is an organophosphate (OP)-degrading enzyme from Enterobacter aerogenes (GpdQ). Although GpdQ is part of a pathway that is used by bacteria to degrade glycerolphosphoesters, it hydrolyzes a variety of other phosphodiesters and displays low levels of activity against phosphomono- and triesters. Such a promiscuous nature may have assisted the apparent recent evolution of some binuclear metallohydrolases to deal with situations created by human intervention such as OP pesticides in the environment. OP pesticides were first used approximately 70 years ago, and therefore the enzymes that bacteria use to degrade them must have evolved very quickly on the evolutionary time scale. The promiscuous nature of enzymes such as GpdQ makes them ideal candidates for the application of directed evolution to produce new enzymes that can be used in bioremediation and against chemical warfare. In this Account, we review the mechanisms employed by binuclear

  14. Synthesis, characterization and biological activities of some new chromium molybdenum and tungsten complexes with 2,6-diaminopyridine

    NASA Astrophysics Data System (ADS)

    Soliman, Ahmed A.; Ali, Saadia A.; Marei, Amany H.; Nassar, Doaa H.

    2012-04-01

    The reactions of [M(CO)6], M = Cr, Mo, W with 2,6-diaminopyridine (dap) in ethanol was carried out under sun light and microwave irradiation routes of synthesis and compared with the traditional thermal reflux method. All routes resulted in the formation of the binuclear oxo complexes with the general formulas [M2(O)4(dap)2]. The prepared complexes were characterized using elemental analysis, IR, 1HNMR, mass spectrometry and magnetic measurement. The biological activity of dap and its complexes as antibacterial and antifungal reagents have been screened.

  15. [Biologically active food additives].

    PubMed

    Velichko, M A; Shevchenko, V P

    1998-07-01

    More than half out of 40 projects for the medical science development by the year of 2000 have been connected with the bio-active edible additives that are called "the food of XXI century", non-pharmacological means for many diseases. Most of these additives--nutricevtics and parapharmacevtics--are intended for the enrichment of food rations for the sick or healthy people. The ecologicaly safest and most effective are combined domestic adaptogens with immuno-modulating and antioxidating action that give anabolic and stimulating effect,--"leveton", "phytoton" and "adapton". The MKTs-229 tablets are residue discharge means. For atherosclerosis and general adiposis they recommend "tsar tablets" and "aiconol (ikhtien)"--on the base of cod-liver oil or "splat" made out of seaweed (algae). All these preparations have been clinically tested and received hygiene certificates from the Institute of Dietology of the Russian Academy of Medical Science. PMID:9752776

  16. Solar Energy Project, Activities: Biology.

    ERIC Educational Resources Information Center

    Tullock, Bruce, Ed.; And Others

    This guide contains lesson plans and outlines of science activities which present concepts of solar energy in the context of biology experiments. Each unit presents an introduction; objectives; skills and knowledge needed; materials; methods; questions; recommendations for further work; and a teacher information sheet. The teacher information…

  17. Biological activity of ionene polymers

    NASA Technical Reports Server (NTRS)

    Rembaum, A.

    1973-01-01

    Ionene polymers are polyammonium salts with positive nitrogens in the backbone, resulting from the polycondensation of diamines with dihalides or from the polycondensation of halo amines. The mechanism of formation of ionene polymers of different structures and their biological activity is reviewed. The antimicrobial and antifungal properties are compared with low molecular weight ammonium salts. Ionenes were found to combine with DNA by means of ionic bonds to yield similar complexes to those obtained with polyamines (spermine and spermidine). They also combine with nerve cell receptors and exercise a more powerful and longer duration ganglionic blocking action than their monomeric analogs. The antiheparin activity of ionenes and the thromboresistance of elastomeric ionene heparin coatings is described. The enhanced biological activity of ionenes as compared with low molecular weight compounds is attributed to a cooperative effect of a large number of positive charges on the polymeric chains.

  18. Molecular characteristics versus biological activity

    USGS Publications Warehouse

    Applegate, Vernon C.; Smith, Manning A.; Willeford, Bennett R.

    1967-01-01

    The molecular characteristics of mononitrophenols containing halogens not only play a key role in their biological activity but provide a novel example of selective toxicity among vertebrate animals. It has been reported that efforts to control the parasitic sea lamprey in the Great Lakes are directed at present to the applications of a selective toxicant to streams inhabited by lamprey larvae. Since 1961, the larvicide that has been used almost exclusively in the control program has been 3-trifluoromethyl-4-nitrophenol (TFM). However, this is only one of about 15 closely related compounds, all halogen-containing mononitrophenols, that display a selectively toxic action upon lampreys. Although not all of the halogenated mononitrophenols are selectively toxic to lampreys (in fact, fewer than half of those tested), no other group of related compounds has displayed any useful larvicidal activity except for the substituted nitrosalicylanilides.

  19. Concepts for Biologically Active Peptides

    PubMed Central

    Kastin, Abba J.; Pan, Weihong

    2012-01-01

    Here we review a unique aspect of CNS research on biologically active peptides that started against a background of prevalent dogmas but ended by exerting considerable influence on the field. During the course of refuting some doctrines, we introduced several concepts that were unconventional and paradigm-shifting at the time. We showed that (1) hypothalamic peptides can act ‘up’ on the brain as well as ‘down’ on the pituitary, (2) peripheral peptides can affect the brain, (3) peptides can cross the blood-brain barrier, (4) the actions of peptides can persist longer than their half-lives in blood, (5) perinatal administration of peptides can exert actions persisting into adulthood, (6) a single peptide can have more than one action, (7) dose-response relationships of peptides need not be linear, (8) the brain produces antiopiate as well as opiate peptides, (9) there is a selective high affinity endogenous peptide ligand for the mu-opiate receptor, (10) a peptide’s name does not restrict its effects, and (11) astrocytes assume an active role in response to metabolic disturbance and hyperleptinemia. The evolving questions in our laboratories reflect the diligent effort of the neuropeptide community to identify the roles of peptides in the CNS. The next decade is expected to see greater progress in the following areas: (a) interactions of peptides with other molecules in the CNS; (b) peptide involvement in cell-cell interactions; and (c) peptides in neuropsychiatric, autoimmune, and neurodegenerative diseases. The development of peptidomics and gene silencing approaches will expedite the formation of many new concepts in a new era. PMID:20726835

  20. A review exploring biological activities of hydrazones

    PubMed Central

    Verma, Garima; Marella, Akranth; Shaquiquzzaman, Mohammad; Akhtar, Mymoona; Ali, Mohammad Rahmat; Alam, Mohammad Mumtaz

    2014-01-01

    The development of novel compounds, hydrazones has shown that they possess a wide variety of biological activities viz. antimicrobial, anticonvulsant, antidepressant, anti-inflammatory, analgesic, antiplatelet, antimalarial, anticancer, antifungal, antitubercular, antiviral, cardio protective etc., Hydrazones/azomethines/imines possess-NHN = CH- and constitute an important class of compounds for new drug development. A number of researchers have synthesized and evaluated the biological activities of hydrazones. This review aims at highlighting the diverse biological activities of hydrazones. PMID:24741273

  1. Synthesis, spectral characterization, molecular modeling and antimicrobial activity studies on 2-aminopyridine-cyclodiphosph(V)azane derivative and its homo-binuclear zinc(II) complexes

    NASA Astrophysics Data System (ADS)

    Alaghaz, Abdel-Nasser M. A.

    2014-06-01

    Complexes of zinc(II) of general composition [Zn2(L)X2(H2O)4]nH2O have been synthesized [L = 1,3-dipyridyl-2,4-dioxo-2‧,4‧-bis(2-iminopyridine)cyclodi-phosph(V)azane and X = NO3-; n = 2, OAc-; n = 1, SO42-; n = 2 and Cl-; n = 2]. The elemental analysis, molar conductance measurements, mass, IR, UV, NMR (1H and 31P), TGA, DTA, SEM and XRD spectral studies of the compounds led to the conclusion that the cyclodiphosph(V)azane ligand (H2L) acts as a bidentate manner per zinc ion. The cyclodiphosph(V)azane ligand forms hexa-coordinated complexes having octahedral geometry for Zn(II) complexes. The elemental analyses and mass spectral data have justified the [Zn2(L)X2(H2O)4]nH2O composition of complexes. Infrared spectra of the zinc complexes indicate deprotonation and coordination of the imine NH. It also confirms that nitrogen atoms of the pyridine group contribute to the complexation. The X-ray powder diffraction (XRD) was performed of [Zn2L(SO4)2(H2O)4]2H2O complex. The XRD patterns indicate crystalline nature for the [Zn2L(SO4)2(H2O)4]2H2O complex. The measured low molar conductance values in dimethylformamide indicate that the complexes are non-electrolyte nature. The surface morphology (SEM) of the cyclodiphosph(V)azane ligand and the [Zn2L(NO3)2(H2O)4]2H2O complex were studied by SEM. The thermal studies suggested that the complexes are more stable as compared to ligand. In molecular modeling the geometries of cyclodiphosph(V)azane ligand H2L and its zinc(II) complexes were fully optimized with respect to the energy using the 6-31G basis set. The cyclodiphosph(V)azane ligand and the zinc(II) complexes have been measured in vitro to judge their antibacterial (Escherichia coli and Staphylococcus aureus) and antifungal (Aspergillus niger and Pencillium chrysogenum) activities.

  2. DNA binding and recognition by binuclear transition metal complexes

    NASA Astrophysics Data System (ADS)

    Liu, Changlin; Yan, Rui; Xu, Yan; Yu, Siwang; Liao, Zhanru; Li, Dongfeng; Xu, Hui-Bie F.

    2001-09-01

    The development of small molecules that can bind and recognize DNA with sequence- or stereo-specificity under physiological conditions has been attracting a great interest in chemistry and biochemistry. Here, spectroscopic characterization and gel electrophoresis methods have been utilized to investigate the DNA binding and recognition by a variety of binuclear transition metal complexes. The result indicate that the structures and charges of binuclear transition metal complexes, compositions of coordination spheres, central metal ions and their coordination unsaturation, and separations between two central metal atoms can exert significant effects on the DNA binding and recognition. If there are not intercalative ligands into DNA base pairs or kinetically substitutable ligands by DNA phosphate groups within coordination sphere, the coordination saturation and compact binuclear transition metal complexes weaker bind to DNA than the coordination unsaturation and extended ones to DNA. Since the different transtiometal ions exhibit different affinities to DNA phosphate oxygen atoms, the binding interactions between their binuclear complexes and DNA are controlled by the affinity. He binuclear complexes with one or more negative charges lead to a consequence that they can not efficient associate with DNA, because DNA phosphodiester backbone is negatively charged. Whenthe separations between two central transition metal atoms is more than the distance between two DNA base pairs, the binuclear complexes could bind and recognize the DNA sequence with two or more base pairs. The protonated and positively charged ligands can strengthen the DNA binding and recognition by these binuclear metal complexes. Based on such DNA binding and recognition principles, the binuclear zinc complex designed in the study preferentially bind and recognize the following DNA sequence on pBR322 DNA with binding constant K.

  3. Spectroscopic and biological studies of new binuclear metal complexes of a tridentate ONS hydrazone ligand derived from 4-amino-6-methyl-3-thioxo-3,4-dihydro-1,2,4-triazin-5(2H)-one and 4,6-diacetylresorcinol

    NASA Astrophysics Data System (ADS)

    Adly, Omima M. I.; Emara, Adel A. A.

    2014-11-01

    The binuclear hydrazone, H2L, ligand derived from 4-amino-6-methyl-3-thioxo-3,4-dihydro-1,2,4-triazin-5(2H)-one and 4,6-diacetylresorcinol, in the molar ratio 2:1, and its copper(II), nickel(II), cobalt(II), zinc(II), cadmium(II), cerium(III), iron(III), oxovanadium(IV) and dioxouranium(VI) complexes have been synthesized. Structures of the ligand and its metal complexes were characterized by elemental analyses, spectral (infrared, electronic, mass, 1H NMR and ESR) data, magnetic susceptibility, molar conductivity measurements and thermal gravimetric analysis (TGA). The ligand acts as dibasic with two ONS tridentate sites. The bonding sites are the azomethine nitrogen, phenolate oxygen and sulfur atoms. The metal complexes exhibit different geometrical arrangements such as square planer, tetrahedral and octahedral. The Coats-Redfern equation was used to calculate the kinetic and thermodynamic parameters for the different thermal decomposition steps of some complexes. The ligand and its metal complexes showed antimicrobial activity towards Gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis), Gram-negative bacteria (Salmonella typhimurium and Escherichia coli), yeast (Candida albicans) and fungus (Aspergillus fumigatus). Structural parameters of the ligand and its metal complexes were theoretically computed on the basis of semiempirical PM3 level, and the results were correlated with their experimental data.

  4. Spectroscopic and biological studies of new binuclear metal complexes of a tridentate ONS hydrazone ligand derived from 4-amino-6-methyl-3-thioxo-3,4-dihydro-1,2,4-triazin-5(2H)-one and 4,6-diacetylresorcinol.

    PubMed

    Adly, Omima M I; Emara, Adel A A

    2014-11-11

    The binuclear hydrazone, H2L, ligand derived from 4-amino-6-methyl-3-thioxo-3,4-dihydro-1,2,4-triazin-5(2H)-one and 4,6-diacetylresorcinol, in the molar ratio 2:1, and its copper(II), nickel(II), cobalt(II), zinc(II), cadmium(II), cerium(III), iron(III), oxovanadium(IV) and dioxouranium(VI) complexes have been synthesized. Structures of the ligand and its metal complexes were characterized by elemental analyses, spectral (infrared, electronic, mass, 1H NMR and ESR) data, magnetic susceptibility, molar conductivity measurements and thermal gravimetric analysis (TGA). The ligand acts as dibasic with two ONS tridentate sites. The bonding sites are the azomethine nitrogen, phenolate oxygen and sulfur atoms. The metal complexes exhibit different geometrical arrangements such as square planer, tetrahedral and octahedral. The Coats-Redfern equation was used to calculate the kinetic and thermodynamic parameters for the different thermal decomposition steps of some complexes. The ligand and its metal complexes showed antimicrobial activity towards Gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis), Gram-negative bacteria (Salmonella typhimurium and Escherichia coli), yeast (Candida albicans) and fungus (Aspergillus fumigatus). Structural parameters of the ligand and its metal complexes were theoretically computed on the basis of semiempirical PM3 level, and the results were correlated with their experimental data. PMID:24858350

  5. [Biological activity of probiotic microorganisms].

    PubMed

    Novik, G I; Samartsev, A A; Astapovich, N I; Kavrus, M A; Mikhaliuk, A N

    2006-01-01

    Adaptation of bifidobacteria and lactic acid bacteria to nutrient media with increased concentrations of bile (1%) and protein substrates of animal origin allowed the variants resistant to bile and displaying a high production of proteolytic enzymes (active within the pH range of 2.5-9.0) to be selected. Administration of the preparations involving the selected bifidobacteria and lactic acid bacteria assisted in the normalization of the intestinal microflora and activation of protein metabolism in the organism of animals. Specifically, it increased the total protein level in blood serum and redistributed protein fractions, increasing the content of globulins and decreasing albumin concentration. PMID:16761572

  6. Biological activities of heparan sulfate.

    PubMed

    Arumugam, Muthuvel; Giji, Sadhasivam

    2014-01-01

    Heparan sulfate was isolated from two bivalve mollusks such as Tridacna maxima and Perna viridis. The isolated heparin was quantified in crude as well as purified samples and they were estimated as 2.72 and 2.2g/kg (crude) and 260 and 248 mg/g (purified) in T. maxima and P. viridis, respectively. Both the bivalves showed the anticoagulant activity of the crude and purified sample as 20,128 USP units/kg and 7.4 USP units/mg, 39,000 USP units/kg and 75 USP units/mg, 9460 USP units/kg and 4.3 USP units/mg, and 13,392 USP units/kg and 54 USP units/mg correspondingly in T. maxima and P. viridis. The antiproliferative activity that was studied with pulmonary artery smooth muscle cells using RPMI media reported that the result is in a dose-dependent manner. Among the two clams, P. viridis showed more antiproliferative activity than that of T. maxima. PMID:25081081

  7. Elsholtzia: phytochemistry and biological activities

    PubMed Central

    2012-01-01

    Plants of the genus Elsholtzia (Lamiaceae) have a long history of medicinal use in folk. The phytochemical investigations revealed the presence of flavonoids, phenylpropanoids, terpenoids, and other compounds. Abundant volatile components are also identified. Pure compounds, volatile constituents and crude extracts from the genus exhibited a wide spectrum of in vitro and in vivo pharmacological activities. The aims of this review hopefully provide comprehensive information on the distribution, phytochemistry, volatile components, and pharmacological research of Elsholtzia for exploring the potential and advance researches. PMID:23216850

  8. Xanthane sesquiterpenoids: structure, synthesis and biological activity.

    PubMed

    Vasas, Andrea; Hohmann, Judit

    2011-04-01

    The aim of this review is to survey the naturally occurring xanthanes and xanthanolides, their structures, biological activities, structure–activity relationships and synthesis. There has been no comprehensive review of this topic previously. On the basis of 126 references, 112 compounds are summarized. PMID:21321751

  9. Marine Biology Activities. Ocean Related Curriculum Activities.

    ERIC Educational Resources Information Center

    Pauls, John

    The ocean affects all of our lives. Therefore, awareness of and information about the interconnections between humans and oceans are prerequisites to making sound decisions for the future. Project ORCA (Ocean Related Curriculum Activities) has developed interdisciplinary curriculum materials designed to meet the needs of students and teachers…

  10. Perylenequinones: Isolation, Synthesis, and Biological Activity

    PubMed Central

    Mulrooey, Carol A.; O'Brien, Erin M.; Morgan, Barbara J.

    2013-01-01

    The perylenequinones are a novel class of natural products characterized by pentacyclic conjugated chromophore giving rise to photoactivity. Potentially useful light-activated biological activity, targeting protein kinase C (PKC), has been identified for several of the natural products. Recently discovered new members of this class of compound, as well as several related phenanthroperylenequinones, are reviewed. Natural product modifications that improve biological profiles, and avenues for the total synthesis of analogs, which are not available from the natural product series, are outlined. An overview of structure/function relationships is provided. PMID:24039544

  11. New biologically active hydrogen sulfide donors.

    PubMed

    Roger, Thomas; Raynaud, Francoise; Bouillaud, Frédéric; Ransy, Céline; Simonet, Serge; Crespo, Christine; Bourguignon, Marie-Pierre; Villeneuve, Nicole; Vilaine, Jean-Paul; Artaud, Isabelle; Galardon, Erwan

    2013-11-25

    Generous donors: The dithioperoxyanhydrides (CH3 COS)2 , (PhCOS)2 , CH3 COSSCO2 Me and PhCOSSCO2 Me act as thiol-activated hydrogen sulfide donors in aqueous buffer solution. The most efficient donor (CH3 COS)2 can induce a biological response in cells, and advantageously replace hydrogen sulfide in ex vivo vascular studies. PMID:24115650

  12. [Biologically Active Peptides of King Crab Hepatopancreas].

    PubMed

    Bogdanov, V V; Berezin, B B; Il'ina, A P; Yamskova, V P; Yamskov, I A

    2015-01-01

    Substances of a peptide nature isolated from the hepatopancreas of the king crab Paralithodes camtschaticus exhibited physicochemical properties and membranotropic and specific activities similar to those of membranotropic homeostatic tissue-specific bioregulators previously found in different mammalian and plant tissues. Their biological effect on vertebrate tissues was demonstrated on a model of roller organotypic cultivation of Pleurodeles waltl newt liver tissue. PMID:26353409

  13. Loranthus micranthus Linn.: Biological Activities and Phytochemistry

    PubMed Central

    Zorofchian Moghadamtousi, Soheil; Hajrezaei, Maryam; Abdul Kadir, Habsah

    2013-01-01

    Loranthus micranthus Linn. is a medicinal plant from the Loranthaceae family commonly known as an eastern Nigeria species of the African mistletoe and is widely used in folkloric medicine to cure various ailments and diseases. It is semiparasitic plant because of growing on various host trees and shrubs and absorbing mineral nutrition and water from respective host. Hence, the phytochemicals and biological activities of L. micranthus demonstrated strong host and harvesting period dependency. The leaves have been proved to possess immunomodulatory, antidiabetic, antimicrobial, antihypertensive, antioxidant, antidiarrhoeal, and hypolipidemic activities. This review summarizes the information and findings concerning the current knowledge on the biological activities, pharmacological properties, toxicity, and chemical constituents of Loranthus micranthus. PMID:24109490

  14. Glycosides from marine sponges (Porifera, Demospongiae): structures, taxonomical distribution, biological activities and biological roles.

    PubMed

    Kalinin, Vladimir I; Ivanchina, Natalia V; Krasokhin, Vladimir B; Makarieva, Tatyana N; Stonik, Valentin A

    2012-08-01

    Literature data about glycosides from sponges (Porifera, Demospongiae) are reviewed. Structural diversity, biological activities, taxonomic distribution and biological functions of these natural products are discussed. PMID:23015769

  15. Glycosides from Marine Sponges (Porifera, Demospongiae): Structures, Taxonomical Distribution, Biological Activities and Biological Roles

    PubMed Central

    Kalinin, Vladimir I.; Ivanchina, Natalia V.; Krasokhin, Vladimir B.; Makarieva, Tatyana N.; Stonik, Valentin A.

    2012-01-01

    Literature data about glycosides from sponges (Porifera, Demospongiae) are reviewed. Structural diversity, biological activities, taxonomic distribution and biological functions of these natural products are discussed. PMID:23015769

  16. Isoflavones: estrogenic activity, biological effect and bioavailability.

    PubMed

    Vitale, Daniela Cristina; Piazza, Cateno; Melilli, Barbara; Drago, Filippo; Salomone, Salvatore

    2013-03-01

    Isoflavones are phytoestrogens with potent estrogenic activity; genistein, daidzein and glycitein are the most active isoflavones found in soy beans. Phytoestrogens have similarity in structure with the human female hormone 17-β-estradiol, which can bind to both alpha and beta estrogen receptors, and mimic the action of estrogens on target organs, thereby exerting many health benefits when used in some hormone-dependent diseases. Numerous clinical studies claim benefits of genistein and daidzein in chemoprevention of breast and prostate cancer, cardiovascular disease and osteoporosis as well as in relieving postmenopausal symptoms. The ability of isoflavones to prevent cancer and other chronic diseases largely depends on pharmacokinetic properties of these compounds, in particular absorption and distribution to the target tissue. The chemical form in which isoflavones occur is important because it influences their bioavailability and, therefore, their biological activity. Glucose-conjugated isoflavones are highly polar, water-soluble compounds. They are hardly absorbed by the intestinal epithelium and have weaker biological activities than the corresponding aglycone. Different microbial families of colon can transform glycosylated isoflavones into aglycones. Clinical studies show important differences between the aglycone and conjugated forms of genistein and daidzein. The evaluation of isoflavone metabolism and bioavailability is crucial to understanding their biological effects. Lipid-based formulations such as drug incorporation into oils, emulsions and self-microemulsifying formulations have been introduced to increase bioavailability. Complexation with cyclodextrin also represent a valid method to improve the physicochemical characteristics of these substances in order to be absorbed and distributed to target tissues. We review and discuss pharmacokinetic issues that critically influence the biological activity of isoflavones. PMID:23161396

  17. Biological activities of selected basidiomycetes from Yemen.

    PubMed

    Al-Fatimi, M; Schröder, G; Kreisel, H; Lindequist, U

    2013-03-01

    In a previous paper we demonstrated the results of biological screening of Yemeni basidiomycetes. The present study was aimed to investigate the antimicrobial and the antioxidant activity of further basidiomycetes collected in Yemen. Dichloromethane, methanol and aqueous extracts of the fruiting bodies of 25 species were screened in vitro for their antibacterial activities against three Gram-positive bacteria (Staphyloccocus aureus, Bacillus subtilis, Micrococcus flavus) and two Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa), against six human fungal pathogens (Candida albicans, Candida krusei, Aspergillus fumigatus, Mucor sp., Microsporum gypseum, Trichophyton mentagrophytes) and against one non human pathogenic fungus (Candida maltosa). The results indicated that 75 extracts exhibited activity against one or more of the bacteria. The methanol extracts of Agaricus cf. bernardii, Agrocybe pediades, Chlorophyllum molybdites, Coriolopsis polyzona, Ganoderma xylonoides, Pycnoporus sanguineus, Trametes lactinea and Trametes cingulata showed activity against all tested bacteria. The highest antibacterial activity was exhibited by methanol extracts from Chlorophyllum molybdites, Ganoderma xylonoides and Trametes cingulata and Agaricus cf. bernardii, Agrocybe pediades, Coriolopsis polyzona, Pycnoporus sanguineus and Trametes lactinea. The methanol extracts of Chlorophyllum molybdites, Ganoderma xylonoides and Pycnoporus sanguineus showed considerable antifungal activities against the tested fungal strains. Strong antioxidative effects employing the DPPH assay were exhibited by methanol extracts from Chlorophyllum molybdites, Ganoderma xylonoides, Hexagonia velutina, Pycnoporus sanguineus, Trametes lactinea and Trametes cingulata. Our previous and presented studies about 48 basidiomycetes collected in Yemen provide evidence that basidiomycetes from the Arabic region so far should attract more attention as potential source for new biologically active

  18. Mononuclear and Binuclear Ruthenium(II) Complexes Containing 2,2'-Bipyridine or 1,10-Phenanthroline and Pyrazole-3,5-Bis(benzimidazole). Synthesis, Structure, Isomerism, Spectroscopy, and Proton-Coupled Redox Activity.

    PubMed

    Baitalik, Sujoy; Flörke, Ulrich; Nag, Kamalaksha

    1999-07-12

    A number of mixed-ligand mononuclear and binuclear ruthenium(II) complexes of composition [(bpy)(2)Ru(H(3)pzbzim)](ClO(4))(2).2H(2)O (1), [(phen)(2)Ru(H(3)pzbzim)](ClO(4))(2).3H(2)O (2), [(bpy)(2)Ru(H(2)pzbzim)Ru(bpy)(2)](ClO(4))(3).5H(2)O (3), [(phen)(2)Ru(H(2)pzbzim)Ru(phen)(2)](ClO(4))(3).4H(2)O (4), [(bpy)(2)Ru(H(2)pzbzim)Ru(phen)(2)](ClO(4))(3).4H(2)O (5), [(bpy)(2)Ru(pzbzim)Ru(bpy)(2)](ClO(4)).3H(2)O (6), and [(phen)(2)Ru(pzbzim)Ru(phen)(2)](ClO(4)).2H(2)O (7), where H(3)pzbzim = pyrazole-3,5-bis(benzimidazole), bpy = 2,2'-bipyridine, and phen = 1,10-phenanthroline, have been prepared and characterized. Complexes 3-5 isolated as mixtures of diastereoisomers have been separated by fractional recrystallization. In the cases of 3 and 4, the meso (LambdaDelta) and racemate (rac) (LambdaLambda, DeltaDelta) forms, and for 5, two enantiomeric pairs [(LambdaDelta, DeltaLambda) and (LambdaLambda, DeltaDelta)] have been obtained. These, as well as the meso and rac diastereoisomers of 6, have been characterized by (1)H and (13)C NMR spectroscopy. The crystal structure of the meso (LambdaDelta) form of 3 (C(57)H(53)N(14)Cl(3)O(17)Ru(2)) has been determined, which crystallizes in the monoclinic space group P2(1)/c with a = 11.672(2) Å, b = 41.696(9) Å, c = 12.871(2) Å, beta = 90.03(2)(o), and Z = 4. The acid-base and redox chemistry of the binuclear complexes has been studied over the pH range 1-12 in acetonitrile-water (3:2) medium. The equilibrium constants of the species involving protonation and deprotonation of the benzimidazole NH protons and the metal oxidation states covering +2 and +3 have been evaluated by spectrophotometric and cyclic voltammetric measurements. During spectrophotometric titrations of the complexes with cerium(IV), the metal-to-ligand charge transfer transitions are replaced by the newly generated ligand-to-metal charge transfer transition. The luminescence spectra of the complexes in solution (at 298 K) and in frozen glass (at 77 K) and

  19. Biologically active compounds from Aphyllophorales (polypore) fungi.

    PubMed

    Zjawiony, Jordan K

    2004-02-01

    This review describes biologically active natural products isolated from Aphyllophorales, many of which are known as polypores. Polypores are a large group of terrestrial fungi of the phylum Basdiomycota (basidiomycetes), and they along with certain Ascomycota are a major source of pharmacologically active substances. There are about 25 000 species of basidiomycetes, of which about 500 are members of the Aphyllophorales, a polyphyletic group that contains the polypores. Many of these fungi have circumboreal distributions in North America, Europe, and Asia and broad distributions on all inhabited continents and Africa; only a small number of the most common species with the most obvious fruiting bodies (basidiocarps) have been evaluated for biological activity. An estimated 75% of polypore fungi that have been tested show strong antimicrobial activity, and these may constitute a good source for developing new antibiotics. Numerous compounds from these fungi also display antiviral, cytotoxic, and/or antineoplastic activities. Additional important components of this vast arsenal of compounds are polysaccharides derived from the fungal cell walls. These compounds have attracted significant attention in recent years because of their immunomodulatory activities, resulting in antitumor effects. These high molecular weight compounds, often called biological response modifiers (BRM), or immunopotentiators, prevent carcinogenesis, show direct anticancer effects, and prevent tumor metastasis. Some of the protein-bound polysaccharides from polypores and other basidiomycetes have found their way to the market in Japan as anticancer drugs. Finally, numerous compounds with cardiovascular, phytotoxic, immunomodulatory, analgesic, antidiabetic, antioxidant, insecticidal, and nematocidal activities, isolated from polypores, are also presented. In fact many of the fungi mentioned in this paper have long been used in herbal medicine, including polypores such as Ganoderma lucidum

  20. Monitoring Biological Activity at Geothermal Power Plants

    SciTech Connect

    Peter Pryfogle

    2005-09-01

    The economic impact of microbial growth in geothermal power plants has been estimated to be as high as $500,000 annually for a 100 MWe plant. Many methods are available to monitor biological activity at these facilities; however, very few plants have any on-line monitoring program in place. Metal coupon, selective culturing (MPN), total organic carbon (TOC), adenosine triphosphate (ATP), respirometry, phospholipid fatty acid (PLFA), and denaturing gradient gel electrophoresis (DGGE) characterizations have been conducted using water samples collected from geothermal plants located in California and Utah. In addition, the on-line performance of a commercial electrochemical monitor, the BIoGEORGE?, has been evaluated during extended deployments at geothermal facilities. This report provides a review of these techniques, presents data on their application from laboratory and field studies, and discusses their value in characterizing and monitoring biological activities at geothermal power plants.

  1. Perspectives on Biologically Active Camptothecin Derivatives

    PubMed Central

    Liu, Ying-Qian; Li, Wen-Qun; Morris-Natschke, Susan L.; Qian, Keduo; Yang, Liu; Zhu, Gao-Xiang; Wu, Xiao-Bing; Chen, An-Liang; Zhang, Shao-Yong; Song, Zi-Long; Lee, Kuo-Hsiung

    2015-01-01

    Camptothecins (CPTs) are cytotoxic natural alkaloids that specifically target DNA topoisomerase I. Research on CPTs has undergone a significant evolution from the initial discovery of CPT in the late 1960s through the study of synthetic small molecule derivatives to investigation of macromolecular constructs and formulations. Over the past years, intensive medicinal chemistry efforts have generated numerous CPT derivatives. Three derivatives, topotecan, irinotecan, and belotecan, are currently prescribed as anticancer drugs, and several related compounds are now in clinical trials. Interest in other biological effects, besides anticancer activity, of CPTs is also growing exponentially, as indicated by the large number of publications on the subject during the last decades. Therefore, the main focus of the present review is to provide an ample but condensed overview on various biological activities of CPT derivatives, in addition to continued up-to-date coverage of anticancer effects. PMID:25808858

  2. Synthesis, spectroscopic, coordination and biological activities of some organometallic complexes derived from thio-Schiff base ligands

    PubMed Central

    Abou-Hussein, Azza A.; Linert, Wolfgang

    2014-01-01

    Two series of mono- and binuclear complexes cyclic or acyclic thio-ferocine Schiff base ligands, derived from the condensation of 2-aminobenzenthiol (L) with monoacetyl ferrocene in the molar ratio 1:1 or in the molar ratio 1:2 for diacetyl ferocine have been prepared. The condensation reactions yield the corresponding Schiff Base ligands, HLa-Maf and H2Lb-Daf. The chelation of the ligands to metal ions occurs through the sulfur of the thiol group as well as the nitrogen atoms of the azomethine group of the ligands. HLa-Maf acts as monobasic bidentate or dibasic tetradentate, while H2Lb-Daf behaves as twice negatively cargend tetradentate ligand. The structures of these ligands were elucidated by elemental analysis, infrared, ultraviolet–visible spectra, as well as 1H NMR spectra. Reactions of the Schiff bases ligands with ruthenium(III), oxovanadium(IV) and dioxouranium(VI) afforded the corresponding transition metal complexes. The properties of the newly prepared complexes were analyse by elemental analyses, infrared, electronic spectra, 1H NMR as well as the magnetic susceptibility and conductivity measurement. The metal complexes exhibits different geometrical arrangements such as octahedral and square pyramidal coordination. Schiff base ligands and their metal complexes were tested against two pathogenic bacteria as Gram-positive and Gram-negative bacteria as well as one kind of fungi to study their biological activity. All the complexes exhibit antibacterial and antifungal activities against these organisms. PMID:24070648

  3. Synthesis, spectroscopic, coordination and biological activities of some organometallic complexes derived from thio-Schiff base ligands

    NASA Astrophysics Data System (ADS)

    Abou-Hussein, Azza A.; Linert, Wolfgang

    2014-01-01

    Two series of mono- and binuclear complexes cyclic or acyclic thio-ferocine Schiff base ligands, derived from the condensation of 2-aminobenzenthiol (L) with monoacetyl ferrocene in the molar ratio 1:1 or in the molar ratio 1:2 for diacetyl ferocine have been prepared. The condensation reactions yield the corresponding Schiff Base ligands, HLa-Maf and H2Lb-Daf. The chelation of the ligands to metal ions occurs through the sulfur of the thiol group as well as the nitrogen atoms of the azomethine group of the ligands. HLa-Maf acts as monobasic bidentate or dibasic tetradentate, while H2Lb-Daf behaves as twice negatively cargend tetradentate ligand. The structures of these ligands were elucidated by elemental analysis, infrared, ultraviolet-visible spectra, as well as 1H NMR spectra. Reactions of the Schiff bases ligands with ruthenium(III), oxovanadium(IV) and dioxouranium(VI) afforded the corresponding transition metal complexes. The properties of the newly prepared complexes were analyse by elemental analyses, infrared, electronic spectra, 1H NMR as well as the magnetic susceptibility and conductivity measurement. The metal complexes exhibits different geometrical arrangements such as octahedral and square pyramidal coordination. Schiff base ligands and their metal complexes were tested against two pathogenic bacteria as Gram-positive and Gram-negative bacteria as well as one kind of fungi to study their biological activity. All the complexes exhibit antibacterial and antifungal activities against these organisms.

  4. Thiol-derivatized minihepcidins retain biological activity.

    PubMed

    Fung, Eileen; Chua, Kristine; Ganz, Tomas; Nemeth, Elizabeta; Ruchala, Piotr

    2015-02-15

    Minihepcidins are small peptides that mimic biological activity of the iron-regulatory hormone hepcidin. Structurally, they contain thiol-free-cysteine residue in position 7 which is crucial for their bioactivity. Nonetheless, free sulfhydryl group is not desirable in pharmaceutical entities as it may lead to dermatological side effects. Moreover free thiol moiety is quite reactive and depending on conditions/reagents may be alkylated and/or oxidized giving various Cys-derivatives: S-alkyl cysteines, sulfoxides, sulfones, disulfides, cysteinesulfinic and cysteic acids. To limit such reactivity and maintain bioactivity of minihepcidin(s) we used thiol-protection strategy based on activated vinyl thioethers. Novel S-protected analogs of physiologically active minihepcidin PR73 were synthesized and tested in vitro showing activity comparable to parental molecule. The most active compound, PR73SH was also tested in vivo showing activity profile analogous to PR73. Collectively, our findings suggest that S-vinyl-derivatization of minihepcidin(s) may be a suitable approach in the development of physiologically active agonists of hepcidin. PMID:25599838

  5. Synthesis and biological activity of polyprenols.

    PubMed

    Zhang, Qiong; Huang, Lixin; Zhang, Caihong; Xie, Pujun; Zhang, Yaolei; Ding, Shasha; Xu, Feng

    2015-10-01

    The polyprenols and their derivatives are highlighted in this study. These lipid linear polymers of isoprenoid residues are widespread in nature from bacteria to human cells. This review primarily presents the synthesis and biological activities of polyprenyl derivatives. Attention is focused on the synthesis and biological activity of dolichols, polyprenyl ester derivatives and polyprenyl amines. Other polyprenyl derivatives, such as oxides of polyprenols, aromatic polyprenols, polyprenyl bromide and polyprenyl sulphates, are mentioned. It is noted that polyprenyl phosphates and polyprenyl-linked glycosylation have better antibacterial, gene therapy and immunomodulating performance, whereas polyprenyl amines have better for antibacterial and antithrombotic activity. Dolichols, polyprenyl acetic esters, polyprenyl phosphates and polyprenyl-linked glycosylation have pharmacological anti-tumour effects. Finally, the postulated prospect of polyprenols and their derivatives are discussed. Further in vivo studies on the above derivatives are needed. The compatibility of polyprenols and their derivatives with other drugs should be studied, and new preparations of polyprenyl derivatives, such as hydrogel glue and release-controlled drugs, are suggested for future research and development. PMID:26358482

  6. Biological Activities of Polyphenols from Grapes

    PubMed Central

    Xia, En-Qin; Deng, Gui-Fang; Guo, Ya-Jun; Li, Hua-Bin

    2010-01-01

    The dietary consumption of grape and its products is associated with a lower incidence of degenerative diseases such as cardiovascular disease and certain types of cancers. Most recent interest has focused on the bioactive phenolic compounds in grape. Anthocyanins, flavanols, flavonols and resveratrol are the most important grape polyphenols because they possess many biological activities, such as antioxidant, cardioprotective, anticancer, anti-inflammation, antiaging and antimicrobial properties. This review summarizes current knowledge on the bioactivities of grape phenolics. The extraction, isolation and identification methods of polyphenols from grape as well as their bioavailability and potential toxicity also are included. PMID:20386657

  7. Fungal proteinaceous compounds with multiple biological activities.

    PubMed

    Ng, Tzi Bun; Cheung, Randy Chi Fai; Wong, Jack Ho; Chan, Yau Sang; Dan, Xiuli; Pan, Wenliang; Wang, Hexiang; Guan, Suzhen; Chan, Ki; Ye, Xiuyun; Liu, Fang; Xia, Lixin; Chan, Wai Yee

    2016-08-01

    Fungi comprise organisms like molds, yeasts and mushrooms. They have been used as food or medicine for a long time. A large number of fungal proteins or peptides with diverse biological activities are considered as antibacterial, antifungal, antiviral and anticancer agents. They encompass proteases, ribosome inactivating proteins, defensins, hemolysins, lectins, laccases, ribonucleases, immunomodulatory proteins, and polysaccharopeptides. The target of the present review is to update the status of the various bioactivities of these fungal proteins and peptides and discuss their therapeutic potential. PMID:27338574

  8. Simultaneous analysis of biologically active aminoalkanephosphonic acids.

    PubMed

    Kudzin, Zbigniew H; Gralak, Dorota K; Andrijewski, Grzegorz; Drabowicz, Józef; Luczak, Jerzy

    2003-05-23

    A new approach for simultaneous analysis of biologically active aminoalkanephosphonic acids, namely glyphosate, phosphonoglycine, phosphonosarcosine, phosphonoalanine, phosphono-beta-alanine, phosphonohomoalanine, phosphono-gamma-homoalanine and glufosinate, is presented. This includes a preliminary 31p NMR analysis of these amino acids, their further derivatization to volatile phosphonates (phosphinates) by means of trifluoroacetic acid-trifluoroacetic anhydride-trimethyl orthoacetate reagent and subsequent analysis of derivatization products using MS and/or GC-MS (chemical ionization and/or electron impact ionization). PMID:12862383

  9. Reconstructing Causal Biological Networks through Active Learning.

    PubMed

    Cho, Hyunghoon; Berger, Bonnie; Peng, Jian

    2016-01-01

    Reverse-engineering of biological networks is a central problem in systems biology. The use of intervention data, such as gene knockouts or knockdowns, is typically used for teasing apart causal relationships among genes. Under time or resource constraints, one needs to carefully choose which intervention experiments to carry out. Previous approaches for selecting most informative interventions have largely been focused on discrete Bayesian networks. However, continuous Bayesian networks are of great practical interest, especially in the study of complex biological systems and their quantitative properties. In this work, we present an efficient, information-theoretic active learning algorithm for Gaussian Bayesian networks (GBNs), which serve as important models for gene regulatory networks. In addition to providing linear-algebraic insights unique to GBNs, leading to significant runtime improvements, we demonstrate the effectiveness of our method on data simulated with GBNs and the DREAM4 network inference challenge data sets. Our method generally leads to faster recovery of underlying network structure and faster convergence to final distribution of confidence scores over candidate graph structures using the full data, in comparison to random selection of intervention experiments. PMID:26930205

  10. Reconstructing Causal Biological Networks through Active Learning

    PubMed Central

    Cho, Hyunghoon; Berger, Bonnie; Peng, Jian

    2016-01-01

    Reverse-engineering of biological networks is a central problem in systems biology. The use of intervention data, such as gene knockouts or knockdowns, is typically used for teasing apart causal relationships among genes. Under time or resource constraints, one needs to carefully choose which intervention experiments to carry out. Previous approaches for selecting most informative interventions have largely been focused on discrete Bayesian networks. However, continuous Bayesian networks are of great practical interest, especially in the study of complex biological systems and their quantitative properties. In this work, we present an efficient, information-theoretic active learning algorithm for Gaussian Bayesian networks (GBNs), which serve as important models for gene regulatory networks. In addition to providing linear-algebraic insights unique to GBNs, leading to significant runtime improvements, we demonstrate the effectiveness of our method on data simulated with GBNs and the DREAM4 network inference challenge data sets. Our method generally leads to faster recovery of underlying network structure and faster convergence to final distribution of confidence scores over candidate graph structures using the full data, in comparison to random selection of intervention experiments. PMID:26930205

  11. Biological activities of Morus celtidifolia leaf extracts.

    PubMed

    Viveros-Valdez, Ezequiel; Oranday-Cárdenas, Azucena; Rivas-Morales, Catalina; Verde-Star, María Julia; Carranza-Rosales, Pilar

    2015-07-01

    The aims of this research were to examine the antibacterial, cytotoxic and antiradical/antioxidant activities of the organic extracts obtained from the leaves of the medicinal plant Morus celtidifolia (Family: Moraceae). To evaluate its antimicrobial properties, M. celtidifolia was tested against the bacteria of medical importance: Bacillus subtilis, Staphyloccocus aureus, Enterococcus faecalis, Escherichia coli, Enterobacter cloacae and Enterobacter aerogenes. Cytotoxic activity was assessed by using the brine shrimp (Artemia salina) lethality assay and also by toxicity screening against human cancer cell lines: MCF-7 (human breast adenocarcinoma) and HeLa (cervix adenocarcinoma). The free radical-scavenging activity was determined by the 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) assay. Results revealed that the hexanic extract has antibacterial activity only against Gram positive strains, while the methanolic extract showed better cytotoxic and antioxidant activities than the non- polar extract with a median lethal dose (LD₅₀) of 125μg/ml, 90μg/ml and 75μg/ml against A. salina, MCF-7 and HeLa cells respectively, and median effective concentration (EC₅₀) of 152μg/ml on radical scavenging assay. This is the first study reporting the biological activities of leaves of Morus celtidifolia. PMID:26142508

  12. SORPTION ON WASTEWATER SOLIDS: ELIMINATION OF BIOLOGICAL ACTIVITY

    EPA Science Inventory

    Sorption was found to be greatly affected by the biological activity in wastewater solids. wo experimental techniques, cyanide treatment and pasteurization, were developed for eliminating the biological activity during isotherm measurements. oth methods are effective; however, pa...

  13. [Bergenia genus - content matters and biological activity].

    PubMed

    Hendrychová, Helena; Tůmová, Lenka

    2012-10-01

    Bergenia, a genus included in the family Saxifragaceae, is a valuable source of healing matters. About 30 Bergenia species are known all over the world. Scientific research is focused on five species mainly distributed in the mountains of Central and East Asia: Bergenia ciliata (Haw.) Sternb., Bergenia stracheyi Engl., Bergenia crassifolia (L.) Fritsch, Bergenia ligulata (Wall.) Engl. and Bergenia himalaica Boriss. These taxons belong to the widely used medicinal herbs in the traditional Chinese, Nepalese and Indian medicine, for therapy of cough and pulmonary diseases, to stop bleeding, to increase immunity and to dissolve kidney or bladder stones. Bergenia consists of many different active compounds including bergenin, norbergenin, catechin, gallic acid, arbutin and other polyphenols. In the Czech Republic this species is commonly grown but it is not used for medical therapy. Individual parts of this plant demonstrate an interesting biological activity, and antibacterial, antiviral, cytoprotective and antioxidant effects. PMID:23256653

  14. Biologically Active Metabolites Synthesized by Microalgae

    PubMed Central

    de Morais, Michele Greque; Vaz, Bruna da Silva; de Morais, Etiele Greque; Costa, Jorge Alberto Vieira

    2015-01-01

    Microalgae are microorganisms that have different morphological, physiological, and genetic traits that confer the ability to produce different biologically active metabolites. Microalgal biotechnology has become a subject of study for various fields, due to the varied bioproducts that can be obtained from these microorganisms. When microalgal cultivation processes are better understood, microalgae can become an environmentally friendly and economically viable source of compounds of interest, because production can be optimized in a controlled culture. The bioactive compounds derived from microalgae have anti-inflammatory, antimicrobial, and antioxidant activities, among others. Furthermore, these microorganisms have the ability to promote health and reduce the risk of the development of degenerative diseases. In this context, the aim of this review is to discuss bioactive metabolites produced by microalgae for possible applications in the life sciences. PMID:26339647

  15. Aminoderivatives of cycloalkanespirohydantoins: synthesis and biological activity.

    PubMed

    Naydenova, Emilia; Pencheva, Nevena; Popova, Julita; Stoyanov, Neyko; Lazarova, Maria; Aleksiev, Boris

    2002-03-01

    3-Aminocycloalkanespiro-5-hydantoins were synthesized and their biological activity was studied. In contrast to hydantoins, these compounds failed to induce either anticonvulsive effects in the central nervous system or inhibitory effects on cholinergic contractions in the enteric nervous system. However, they exerted well pronounced, atropinsensitive, contractile effects on the guinea-pig ileum longitudinal muscle preparations. Structure-activity relationships established allow the assumption that: (i) the reduction of the ring size in the molecule of the spirohydantoins leads to an increase in the potency of the respective analogue to induce contractile effect; (ii) the introduction of -NH2 in position 3 increases the ability of all the compounds studied to exert contractions; (iii) the enlargement of the ring leads to: (1) an increase of the degree of desensitization of the preparations; and (2) a decrease (except 1a) of the potency of the analogues to exert contractile effects. PMID:11989796

  16. Spectroscopic study of biologically active glasses

    NASA Astrophysics Data System (ADS)

    Szumera, M.; Wacławska, I.; Mozgawa, W.; Sitarz, M.

    2005-06-01

    It is known that the chemical activity phenomenon is characteristic for some inorganic glasses and they are able to participate in biological processes of living organisms (plants, animals and human bodies). An example here is the selective removal of silicate-phosphate glass components under the influence of biological solutions, which has been applied in designing glasses acting as ecological fertilizers of controlled release rate of the nutrients for plants. The structure of model silicate-phosphate glasses containing the different amounts of the glass network formers, i.e. Ca 2+ and Mg 2+, as a binding components were studied. These elements besides other are indispensable of the normal growth of plants. In order to establish the function and position occupied by the particular components in the glass structure, the glasses were examined by FTIR spectroscopy (with spectra decomposition) and XRD methods. It has been found that the increasing amount of MgO in the structure of silicate-phosphate glasses causes the formation of domains the structure of which changes systematically from a structure of the cristobalite type to a structure corresponding to forsterite type. Whilst the increasing content of CaO in the structure of silicate-phosphate glasses causes the formation of domains the structure of which changes from a structure typical for cristobalite through one similar to the structure of calcium orthophosphate, to a structure corresponding to calcium silicates. The changing character of domains structure is the reason of different chemical activity of glasses.

  17. Carbon nanomaterials: Biologically active fullerene derivatives.

    PubMed

    Bogdanović, Gordana; Djordjević, Aleksandar

    2016-01-01

    Since their discovery, fullerenes, carbon nanotubes, and graphene attract significant attention of researches in various scientific fields including biomedicine. Nano-scale size and a possibility for diverse surface modifications allow carbon nanoallotropes to become an indispensable nanostructured material in nanotechnologies, including nanomedicine. Manipulation of surface chemistry has created diverse populations of water-soluble derivatives of fullerenes, which exhibit different behaviors. Both non-derivatized and derivatized fullerenes show various biological activities. Cellular processes that underline their toxicity are oxidative, genotoxic, and cytotoxic responses.The antioxidant/cytoprotective properties of fullerenes and derivatives have been considered in the prevention of organ oxidative damage and treatment. The same unique physiochemical properties of nanomaterials may also be associated with potential health hazards. Non-biodegradability and toxicity of carbon nanoparticles still remain a great concern in the area of biomedical application. In this review, we report on basic physical and chemical properties of carbon nano-clusters--fullerenes, nanotubes, and grapheme--their specificities, activities, and potential application in biological systems. Special emphasis is given to our most important results obtained in vitro and in vivo using polyhydroxylated fullerene derivative C₆₀(OH)₂₄. PMID:27483572

  18. Structural characterization by EXAFS spectroscopy of the binuclear iron center in protein A of methane monooxygenase from methylococcus capsulatus (bath)

    SciTech Connect

    Ericson, A.; Hedman, B.; Hodgson, K.O.; Green, J.; Dalton, H.; Bentsen, J.G.; Beer, R.H.; Lippard, S.J.

    1988-03-30

    Soluble methane monooxygenase (MMO) from Methylococcus capsulatus (Bath) activates dioxygen for incorporation into a remarkable variety of substrates including methane, which is required for bacterial growth (eq 1). MMO is a three component CH/sub 4/ + NADH + H/sup +/ + O/sub 2/ /sup MMO/ ..-->.. CH/sub 3/OH + NAD/sup +/ + H/sub 2/O (1) enzyme. Protein A (M/sub r/ 210,000), believed to be the oxygenase component, contains two iron atoms. Protein B (M/sub r/ 15,700) serves a regulatory function and lacks prosthetic groups, while protein C, the reductase component of the enzyme, is an iron-sulfur flavoprotein (M/sub r/ 42,000) responsible for electron transfer from NADH to protein A. Recently, a binuclear iron center was postulated to occur in protein A based on the finding that one-electron reduction gives rise to electron spin resonance (ESR) signals (g 1.95, 1.88, 1.78) very similar to those observed for the binuclear mixed-valence Fe/sub 2/(III,II) centers in semimet hemerythrin (Hr) and purple acid phosphatase (PAP). In conjunction with model studies, extended X-ray absorption fine structure (EXAFS) spectroscopy has proven to be a powerful method for identifying bridged binuclear iron centers in Hr, ribonucleotide reductase (RR), and PAP. Here the authors report iron K-edge EXAFS results on semireduced protein A of MMO which support the occurrence of a binuclear iron center (Fe-Fe distance, 3.41 A), with no short ..mu..-oxo bridge.

  19. Well-defined binuclear chiral spiro copper catalysts for enantioselective N-H insertion.

    PubMed

    Zhu, Shou-Fei; Xu, Bin; Wang, Guo-Peng; Zhou, Qi-Lin

    2012-01-11

    An asymmetric N-H insertion of α-diazoesters with anilines catalyzed by well-defined copper complexes of chiral spiro bisoxazoline ligands was studied in detail. The copper-catalyzed asymmetric N-H insertion of a wide range of α-alkyl-α-diazoacetates with anilines was accomplished with excellent enantioselectivity (up to 98% ee) and provided an efficient method for the preparation of optically active α-amino acid derivatives. A correlation study of the electronic properties of the substrates with the enantioselectivity of the N-H insertion reaction supports a stepwise insertion mechanism, and the significant first-order kinetic isotope effect proves that the proton transfer is most likely the rate-limiting step. A binuclear chiral spiro copper catalyst having 14-electron copper centers, a trans coordination model, a perfect C(2)-symmetric chiral pocket, and significant Cu-Cu interaction was isolated and extensively studied. The novel structure of the binuclear chiral spiro copper catalyst leads to unique reactivity as well as enantioselectivity in the N-H insertion reaction. PMID:22066865

  20. Structural diversity in binuclear complexes of alkaline earth metal ions with 4,6-diacetylresorcinol

    NASA Astrophysics Data System (ADS)

    Shebl, Magdy; Khalil, Saied M. E.; Taha, A.; Mahdi, M. A. N.

    2012-11-01

    A new series of binuclear and mixed-ligand complexes with the general formula: [M 2(LO)yClz]; where M = Mg(II), Ca(II), Sr(II) and Ba(II); H2L = 4,6-diacetylresorcinol, the secondary ligand L' = acetylacetone (acac), 8-hydroxyquinoline (8-HQ) or 2,2'-bipyridyl (Bipy), n = 0-2, m = 1, 2, x = 0, 1, 2, 4, y = 0, 2, 4, 5 and z = 0-2; have been synthesized. They have been characterized by the analytical and spectral methods (IR, 1H NMR and mass) as well as TGA and molar conductivity measurements. The spectroscopic and conductance data suggested that the H2L ligand behaves as a neutral, monobasic or dibasic tetradentate ligand, depending on the basicity of the secondary ligand, through the two phenolic and two carbonyl groups. Binuclear octahedral geometry has been assigned to all of the prepared complexes in various molar ratios 2:2; 2:2:2; 1:2:1 and 1:2:4 (L:M:L'). Molecular orbital calculations were performed for the ligands and their complexes using Hyperchem 7.52 program on the bases of PM3 level and the results were correlated with the experimental data. The ligand and some of its alkaline metal(II) complexes showed antibacterial activity towards some of Gram-positive and Gram-negative bacteria, yeast (Candida albicans) and fungus (Aspergillus fumigatus).

  1. Litchi flavonoids: isolation, identification and biological activity.

    PubMed

    Li, Jiangrong; Jiang, Yueming

    2007-01-01

    The current status of the isolation, identification, biological activity, utilization and development prospects of flavonoids found in litchi fruit pericarp (LFP) tissues is reviewed. LFP tissues account for approximately 15% by weight of the whole fresh fruit and are comprised of significant amount of flavonoids. The major flavonoids in ripe LFP include flavonols and anthocyanins. The major flavanols in the LFP are reported to be procyanidin B4, procyanidin B2 and epicatechin, while cyanindin-3-rutinside, cyanidin-3-glucoside, quercetin-3-rutinosde and quercetin-3-glucoside are identified as the important anthocyanins. Litchi flavanols and anthocyanins exhibit good potential antioxidant activity. The hydroxyl radical and superoxide anion scavenging activities of procyanidin B2 are greater than those of procyanidin B4 and epicatechin, while epicatechin has the highest alpha,alpha-diphenyl-beta-picrylhydrazyl radical (DPPH*) scavenging activity. In addition to the antioxidant activity, LFP extract displays a dose- and time-dependent inhibitory effect on human breast cancer, which could be attributed, in part, to its inhibition of proliferation and induction of apoptosis in cancer cells through upregulation and down-regulation of multiple genes. Furthermore, various anticancer activities are observed for epicatechin, procyanidin B2, procyanidin B4 and the ethyl acetate fraction of LFP tissue extracts. Procyanidin B4 and the ethyl acetate fraction show a stronger inhibitory effect on HELF than MCF-7 proliferation, while epicatechin and procyanidin B2 have lower cytotoxicities towards MCF-7 and HELF than paclitaxel. It is therefore suggested that flavonoids from LFP might be potentially useful components for functional foods and/or anti-breast cancer drugs. PMID:17851427

  2. Biological activity of ruthenium nitrosyl complexes.

    PubMed

    Tfouni, Elia; Truzzi, Daniela Ramos; Tavares, Aline; Gomes, Anderson Jesus; Figueiredo, Leonardo Elias; Franco, Douglas Wagner

    2012-01-01

    Nitric oxide plays an important role in various biological processes, such as neurotransmission, blood pressure control, immunological responses, and antioxidant action. The control of its local concentration, which is crucial for obtaining the desired effect, can be achieved with exogenous NO-carriers. Coordination compounds, in particular ruthenium(III) and (II) amines, are good NO-captors and -deliverers. The chemical and photochemical properties of several ruthenium amine complexes as NO-carriers in vitro and in vivo have been reviewed. These nitrosyl complexes can stimulate mice hippocampus slices, promote the lowering of blood pressure in several in vitro and in vivo models, and control Trypanosoma cruzi and Leishmania major infections, and they are also effective against tumor cells in different models of cancer. These complexes can be activated chemically or photochemically, and the observed biological effects can be attributed to the presence of NO in the compound. Their efficiencies are explained on the basis of the [Ru(II)NO(+)](3+)/[Ru(II)NO(0)](2+) reduction potential, the specific rate constant for NO liberation from the [RuNO](2+) moiety, and the quantum yield of NO release. PMID:22178685

  3. Biologically Active and Antimicrobial Peptides from Plants

    PubMed Central

    Salas, Carlos E.; Badillo-Corona, Jesus A.; Ramírez-Sotelo, Guadalupe; Oliver-Salvador, Carmen

    2015-01-01

    Bioactive peptides are part of an innate response elicited by most living forms. In plants, they are produced ubiquitously in roots, seeds, flowers, stems, and leaves, highlighting their physiological importance. While most of the bioactive peptides produced in plants possess microbicide properties, there is evidence that they are also involved in cellular signaling. Structurally, there is an overall similarity when comparing them with those derived from animal or insect sources. The biological action of bioactive peptides initiates with the binding to the target membrane followed in most cases by membrane permeabilization and rupture. Here we present an overview of what is currently known about bioactive peptides from plants, focusing on their antimicrobial activity and their role in the plant signaling network and offering perspectives on their potential application. PMID:25815307

  4. [Nonequilibrium state of electrochemically activated water and its biological activity].

    PubMed

    Petrushanko, I Iu; Lobyshev, V I

    2001-01-01

    Changes in the physicochemical parameters (pH, redox potential and electroconductivity) of catholyte and anolyte produced by membrane electrolysis of distilled water and dilute (c < 10(-3) M) sodium chloride solutions were studied. The relaxation of these parameters after electrolysis and the influence of catholyte and anolyte on the growth of roots of Tradescantia viridis grafts, the development of duckweed, and the motive activity of infusoria Spirostomum ambiguum were investigated. It was found that the anolyte of distilled water stimulated development of these biological objects. The direction of shift of physicochemical parameters of catholyte and anolyte from equilibrium values and the type of their biological activity (stimulation or inhibition) depend on salt concentration in initial solution. Barbotage of initial distilled water with argon or nitrogen leads to a greater decrease in the redox potential of catholyte during electrolysis. The physicochemical parameters relax to equilibrium values, and the biological activity of catholite and anolyte decreases with time and practically disappears by the end of the day. It was found that the oxidation of reducing agent by atmospheric oxygen is not the sole cause of the relaxation of catalyte redox potential. The increase in the ionic strength of catholite and anolyte by the addition of concentrated sodium chloride after electrolysis decreases the rate of redox potential relaxation several times. The redox potential can be maintained for long periods by freezing. PMID:11449536

  5. Nonexercise activity thermogenesis (NEAT): environment and biology.

    PubMed

    Levine, James A

    2004-05-01

    Nonexercise activity thermogenesis (NEAT) is the energy expended for everything that is not sleeping, eating, or sports-like exercise. It includes the energy expended walking to work, typing, performing yard work, undertaking agricultural tasks, and fidgeting. NEAT can be measured by one of two approaches. The first is to measure or estimate total NEAT. Here, total daily energy expenditure is measured, and from it "basal metabolic rate-plus-thermic effect of food" is subtracted. The second is the factoral approach, whereby the components of NEAT are quantified, and total NEAT is calculated by summing these components. The amount of NEAT that humans perform represents the product of the amount and types of physical activities and the thermogenic cost of each activity. The factors that impact a human's NEAT are readily divisible into environmental factors, such as occupation or dwelling within a "concrete jungle," and biological factors such as weight, gender, and body composition. The combined impact of these factors explains the substantial variance in human NEAT. The variability in NEAT might be viewed as random, but human and animal data contradict this. It appears that changes in NEAT subtly accompany experimentally induced changes in energy balance and are important in the physiology of weight change. Inadequate modulation of NEAT plus a sedentary lifestyle may thus be important in obesity. It then becomes intriguing to dissect mechanistic studies that delineate how NEAT is regulated into neural, peripheral, and humoral factors. A scheme is described in this review in which NEAT corresponds to a carefully regulated "tank" of physical activity that is crucial for weight control. PMID:15102614

  6. Biological Activities of Plant Pigments Betalains.

    PubMed

    Gandía-Herrero, Fernando; Escribano, Josefa; García-Carmona, Francisco

    2016-04-25

    Betalains are a family of natural pigments present in most plants of the order Caryophyllales. They provide colors ranging from yellow to violet to structures that in other plants are colored by anthocyanins. These include not only edible fruits and roots but also flowers, stems, and bracts. The recent characterization of different bioactivities in experiments with betalain containing extracts and purified pigments has renewed the interest of the research community in these molecules used by the food industry as natural colorants. Studies with multiple cancer cell lines have demonstrated a high chemopreventive potential that finds in vitro support in a strong antiradical and antioxidant activity. Experiments in vivo with model animals and bioavailability studies reinforce the possible role played by betalains in the diet. This work provides a critical review of all the claimed biological activities of betalains, showing that the bioactivities described might be supported by the high antiradical capacity of their structural unit, betalamic acid. Although more investigations with purified compounds are needed, the current evidences suggest a strong health-promoting potential. PMID:25118005

  7. Potential biological activity of acacia honey.

    PubMed

    Muhammad, Aliyu; Odunola, Oyeronke A; Ibrahim, Mohammed A; Sallau, Abdullahi B; Erukainure, Ochuko L; Aimola, Idown A; Malami, Ibrahim

    2016-01-01

    Recent advances in functional foods-based research have increasingly become an area of major interest because it affects human health and activities. Functional foods are classes of foods with health promoting and disease preventing properties in addition to multiple nutritional values and of such type is honey. Acacia honey is a type of honey produced by bees (Apis mellifera) fed on Acacia flowers, hence the name. This review focuses on the potential biological activities of Acacia honey which includes quality, antioxidant, immuno-modulatory, antiproliferative and neurological properties at in vitro and in vivo levels. Based on our review, Acacia honey used from various researches is of high purity, contains some bioactive compounds ranging from vitamins, phenolics, flavonoids and fatty acids. It's highly nutritional with strong antioxidant and immuno-modulatory potentials which may therefore be considered a potential candidate for both cancer prevention and treatment. Neurologically, it may be considered as a viable therapeutic agent in the management of Alzheimer's disease. PMID:26709666

  8. Natural phenanthrenes and their biological activity.

    PubMed

    Kovács, Adriána; Vasas, Andrea; Hohmann, Judit

    2008-03-01

    The aim of this review is to survey the various naturally occurring phenanthrene compounds that have been isolated from different plants. Only one review has previously been published on this topic. Gorham (1989) reviewed the structures, biosynthesis, separations and spectroscopy of stilbenes and phenanthrenes. The present study furnishes an overview of the hydroxy or/and methoxy-substituted 9,10-dihydro/phenanthrenes, methylated, prenylated and other monomeric derivatives, dimeric and trimeric phenanthrenes and their biological activities. A fairly large number of phenanthrenes have been reported from higher plants, mainly in the Orchidaceae family, in the species Dendrobium, Bulbophyllum, Eria, Maxillaria, Bletilla, Coelogyna, Cymbidium, Ephemerantha and Epidendrum. A few phenanthrenes have been found in the Hepaticae class and Dioscoreaceae, Combretaceae and Betulaceae families. Their distribution correlates strongly with the taxonomic divisions. These plants have often been used in traditional medicine, and phenanthrenes have therefore been studied for their cytotoxicity, antimicrobial, spasmolytic, anti-inflammatory, antiplatelet aggregation, antiallergic activities and phytotoxicity. On the basis of 120 references, this review covers the phytochemistry and pharmacology of phenanthrenes, describing 252 compounds. This contribution stems from our work on the medicinal plant Tamus communis. PMID:18243254

  9. Binuclear ruthenium(II) complexes for amyloid fibrils recognition

    NASA Astrophysics Data System (ADS)

    Hanczyc, Piotr

    2014-12-01

    Metal-organic compounds represent a unique class of biomarkers with promising photophysical properties useful for imaging. Here interactions of insulin fibrils with two binuclear complexes [μ-(11,11‧-bidppz)(phen)4Ru2]4+ (1) and [μ-C4(cpdppz)(phen)4Ru2]4+ (2) are studied by linear dichroism (LD) and fluorescence. These ruthenium(II) compounds could provide a new generation of amyloid binding chromophores with long lived lifetimes, good luminescence quantum yields for the bound molecules and photo-stability useful in multiphoton luminescence imaging.

  10. Office of Biological Informatics and Outreach geospatial technology activities

    USGS Publications Warehouse

    U.S. Geological Survey

    1998-01-01

    The U.S. Geological Survey (USGS) Office of Biological Informatics and Outreach (OBIO) in Reston, Virginia, and its Center for Biological Informatics (CBI) in Denver, Colorado, provide leadership in the development and use of geospatial technologies to advance the Nation's biological science activities.

  11. Lung biological activity of American attapulgite

    SciTech Connect

    Begin, R.; Masse, S.; Rola-Pleszczynski, M.; Geoffroy, M.; Martel, M.; Desmarais, Y.; Sebastien, P.

    1987-04-01

    Attapulgite is a fibrous mineral industrially consumed at the rate of over a million tons per year but the biological activity of the material is not fully known. To evaluate the in vivo toxicity of the fibrous materials, they exposed the tracheal lobe of 16 sheep to a single exposure of either 100 ml saline, 100 mg UICC asbestos fibers in 100 ml saline, 100 mg short asbestos fibers in 100 ml saline, or 100 mg attapulgite in 100 ml saline. The animals were studied by bronchoalveolar lavage (BAL) at Days 2, 12, 24, 40, and 60 and by autopsy at Day 60. In the saline-exposed sheep, BAL and lung histology did not change. In the UICC asbestos-exposed animals, they reproduced the BAL changes previously reported. In the short asbestos-exposed sheep, there were no significant BAL changes. In the attapulgite sheep, they found significant and sustained increases in total BAL cells, macrophages, neutrophils, fibronectin, lactate dehydrogenase, ..beta..-glucuronidase, but BAL cellularity returned to control levels by Day 60 whereas in the UICC asbestos-exposed sheep, it remained significantly above control. Lung histology demonstrated the characteristic peribronchiolar fibrosing alveolitis in the UICC asbestos-exposed sheep, whereas macrophagic alveolitis with minimal airway distortion was seen in the short asbestos-exposed sheep, whereas macrophagic alveolitis with minimal airway distortion was seen in the short asbestos-exposed sheep and in all of the attapulgite-exposed sheep but three which had typical peribronchiolar alveolitis quite similar to that observed in UICC-exposed sheep, but of lower intensity.

  12. Magnetic and luminescent binuclear double-stranded helicates.

    PubMed

    Cucos, Paula; Tuna, Floriana; Sorace, Lorenzo; Matei, Iulia; Maxim, Catalin; Shova, Sergiu; Gheorghe, Ruxandra; Caneschi, Andrea; Hillebrand, Mihaela; Andruh, Marius

    2014-07-21

    Three new binuclear helicates, [M2L2]·3DMF (M = Co(II), 1, Zn(II), 3) and [Cu2L2]·DMF·0.4H2O (2), have been assembled using the helicand H2L that results from the 2:1 condensation reaction between o-vanillin and 4,4'-diaminodiphenyl ether. The metal ions within the binuclear helicates are tetracoordinated with a distorted tetrahedral geometry. Direct current magnetic characterization and EPR spectroscopy of the Co(II) derivative point to an easy axis type anisotropy for both Co(II) centers, with a separation of at least 55 K between the two doublets. Dynamic susceptibility measurements evidence slow relaxation of the magnetization in an applied dc field. Since the distance between the cobalt ions is quite large (11.59 Å), this is attributed in a first instance to the intrinsic properties of each Co(II) center (single-ion magnet behavior). However, the temperature dependence of the relaxation rate and the absence of slow dynamics in the Zn(II)-doped sample suggest that neither the simple Orbach mechanism nor Raman or direct processes can account for the relaxation, and collective phenomena have to be invoked for the observed behavior. Finally, due to the rigidization of the two organic ligands upon coordination, the pure zinc derivative exhibits fluorescence emission in solution, which was analyzed in terms of fluorescence quantum yields and lifetimes. PMID:24998701

  13. The ice nucleation activity of biological aerosols

    NASA Astrophysics Data System (ADS)

    Grothe, H.; Pummer, B.; Bauer, H.; Bernardi, J.

    2012-04-01

    Primary Biological Aerosol Particles (PBAPs), including bacteria, spores and pollen may be important for several atmospheric processes. Particularly, the ice nucleation caused by PBAPs is a topic of growing interest, since their impact on ice cloud formation and thus on radiative forcing, an important parameter in global climate is not yet fully understood. In laboratory model studies we investigated the ice nucleation activity of selected PBAPs. We studied the immersion mode freezing using water-oil emulsion, which we observed by optical microscopy. We particularly focused on pollen. We show that pollen of different species strongly differ in their ice nucleation behavior. The average freezing temperatures in laboratory experiments range from 240 K to 255 K. As the most efficient nuclei (silver birch, Scots pine and common juniper pollen) have a distribution area up to the Northern timberline, their ice nucleation activity might be a cryoprotective mechanism. For comparison the ice nucleation activity of Snomax, fungal spores, and mushrooms will be discussed as well. In the past, pollen have been rejected as important atmospheric IN, as they are not as abundant in the atmosphere as bacteria or mineral dust and are too heavy to reach higher altitudes. However, in our experiments (Pummer et al. 2011) it turned out that water, which had been in contact with pollen and then been separated from the bodies, nucleates as good as the pollen grains themselves. So the ice nuclei have to be easily-suspendable macromolecules (100-300 kDa) located on the pollen. Once extracted, they can be distributed further through the atmosphere than the heavy pollen grains and so augment the impact of pollen on ice cloud formation even in the upper troposphere. It is widely known, that material from the pollen, like allergens and sugars, can indeed leave the pollen body and be distributed independently. The most probable mechanism is the pollen grain bursting by rain, which releases

  14. The Infusion of Environmental Activities into a Secondary Biology Curriculum

    ERIC Educational Resources Information Center

    Foster, Helen M.

    1976-01-01

    Reviewed are "adventure-type" environmental education activities incorporated into a secondary level biology course. Student wilderness experiences included 24 weekend activities of hiking, bird watching, camping, and cross-country skiing. (SL)

  15. Synthesis, reactivity and biological activity of 5-alkoxymethyluracil analogues

    PubMed Central

    Brulikova, Lucie

    2011-01-01

    Summary This review article summarizes the results of a long-term investigation of 5-alkoxymethyluracil analogues and is aimed, in particular, at methods of syntheses. Most of the presented compounds were synthesized in order to evaluate their biological activity, therefore, a brief survey of biological activity, especially antiviral, cytotoxic and antibacterial, is also reported. PMID:21804865

  16. Multifunctional and biologically active matrices from multicomponent polymeric solutions

    NASA Technical Reports Server (NTRS)

    Kiick, Kristi L. (Inventor); Yamaguchi, Nori (Inventor); Rabolt, John (Inventor); Casper, Cheryl (Inventor)

    2012-01-01

    A functionalized electrospun matrix for the controlled-release of biologically active agents, such as growth factors, is presented. The functionalized matrix comprises a matrix polymer, a compatibilizing polymer and a biomolecule or other small functioning molecule. In certain aspects the electrospun polymer fibers comprise at least one biologically active molecule functionalized with low molecular weight heparin.

  17. Structure/function correlations among coupled binuclear copper proteins through spectroscopic and reactivity studies of NspF

    PubMed Central

    Ginsbach, Jake W.; Kieber-Emmons, Matthew T.; Nomoto, Ryohei; Noguchi, Akio; Ohnishi, Yasuo; Solomon, Edward I.

    2012-01-01

    The terminal step of 4-hydroxy-3-nitrosobenzamide biosynthesis in Streptomyces murayamaensis is performed by NspF, a mono-oxygenase that converts o-aminophenols to the corresponding nitroso product (hydroxyanilinase activity). Previous biochemical characterization of the resting form of NspF suggested that this enzyme belonged to the coupled binuclear copper enzyme (CBC) family. Another member of this enzyme family, tyrosinase, is able to mono-oxygenate monophenols (monophenolase activity) but not o-aminophenols. To gain insight into the unique reactivity of NspF, we have generated and characterized the oxy form of its active site. The observation of spectral features identical to those of oxy-tyrosinase indicates that oxy-NspF contains a Cu2O2 core where peroxide is coordinated in a μ-η2∶ η2 mode, confirming that NspF is a CBC enzyme. This oxy form is found to react with monophenols, indicating that, like tyrosinase, NspF also possesses monophenolase activity. A comparison of the two electrophilic mechanisms for the monophenolase and hydroxyanilinase activity indicates a large geometric change between their respective transition states. The potential for specific interactions between the protein pocket and the substrate in each transition state is discussed within the context of the differential reactivity of this family of enzymes with equivalent μ-η2∶η2 peroxy bridged coupled binuclear copper active sites. PMID:22711806

  18. Milk inhibits the biological activity of ricin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ricin is a highly toxic protein produced by the castor plant Ricinus communis. The toxin is relatively easy to isolate and can be used as a biological weapon. There is great interest in identifying effective inhibitors for ricin. In this study, we demonstrated by three independent assays that compon...

  19. Cyclobutane-Containing Alkaloids: Origin, Synthesis, and Biological Activities

    PubMed Central

    Sergeiko, Anastasia; Poroikov, Vladimir V; Hanuš, Lumir O; Dembitsky, Valery M

    2008-01-01

    Present review describes research on novel natural cyclobutane-containing alkaloids isolated from terrestrial and marine species. More than 60 biological active compounds have been confirmed to have antimicrobial, antibacterial, antitumor, and other activities. The structures, synthesis, origins, and biological activities of a selection of cyclobutane-containing alkaloids are reviewed. With the computer program PASS some additional biological activities are also predicted, which point toward new possible applications of these compounds. This review emphasizes the role of cyclobutane-containing alkaloids as an important source of leads for drug discovery. PMID:19696873

  20. The biology of insecticidal activity and resistance.

    PubMed

    Perry, Trent; Batterham, Philip; Daborn, Phillip J

    2011-07-01

    Identifying insecticide resistance mechanisms is paramount for pest insect control, as the understandings that underpin insect control strategies must provide ways of detecting and managing resistance. Insecticide resistance studies rely heavily on detailed biochemical and genetic analyses. Although there have been many successes, there are also many examples of resistance that still challenge us. As a precursor to rational pest insect control, the biology of the insect, within the contexts of insecticide modes of action and insecticide metabolism, must be well understood. It makes sense to initiate this research in the best model insect system, Drosophila melanogaster, and translate these findings and methodologies to other insects. Here we explore the usefulness of the D. melanogaster model in studying metabolic-based insecticide resistances, target-site mediated resistances and identifying novel insecticide targets, whilst highlighting the importance of having a more complete understanding of insect biology for insecticide studies. PMID:21426939

  1. Biology Research Activities: Teacher's Edition (with Answers).

    ERIC Educational Resources Information Center

    Newman, Barbara

    This book is part of the series "Explorations in Science" which contains enrichment activities for the general science curriculum. Each book in the series contains innovative and traditional projects for both the bright and average, the self-motivated, and those who find activity motivating. Each activity is self-contained and provides everything…

  2. Ficus carica L. (Moraceae): Phytochemistry, Traditional Uses and Biological Activities

    PubMed Central

    Mawa, Shukranul; Husain, Khairana; Jantan, Ibrahim

    2013-01-01

    This paper describes the botanical features of Ficus carica L. (Moraceae), its wide variety of chemical constituents, its use in traditional medicine as remedies for many health problems, and its biological activities. The plant has been used traditionally to treat various ailments such as gastric problems, inflammation, and cancer. Phytochemical studies on the leaves and fruits of the plant have shown that they are rich in phenolics, organic acids, and volatile compounds. However, there is little information on the phytochemicals present in the stem and root. Reports on the biological activities of the plant are mainly on its crude extracts which have been proven to possess many biological activities. Some of the most interesting therapeutic effects include anticancer, hepatoprotective, hypoglycemic, hypolipidemic, and antimicrobial activities. Thus, studies related to identification of the bioactive compounds and correlating them to their biological activities are very useful for further research to explore the potential of F. carica as a source of therapeutic agents. PMID:24159359

  3. Ficus carica L. (Moraceae): Phytochemistry, Traditional Uses and Biological Activities.

    PubMed

    Mawa, Shukranul; Husain, Khairana; Jantan, Ibrahim

    2013-01-01

    This paper describes the botanical features of Ficus carica L. (Moraceae), its wide variety of chemical constituents, its use in traditional medicine as remedies for many health problems, and its biological activities. The plant has been used traditionally to treat various ailments such as gastric problems, inflammation, and cancer. Phytochemical studies on the leaves and fruits of the plant have shown that they are rich in phenolics, organic acids, and volatile compounds. However, there is little information on the phytochemicals present in the stem and root. Reports on the biological activities of the plant are mainly on its crude extracts which have been proven to possess many biological activities. Some of the most interesting therapeutic effects include anticancer, hepatoprotective, hypoglycemic, hypolipidemic, and antimicrobial activities. Thus, studies related to identification of the bioactive compounds and correlating them to their biological activities are very useful for further research to explore the potential of F. carica as a source of therapeutic agents. PMID:24159359

  4. Sensitive bioassay for detection of biologically active ricin in food

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The potential use of ricin as an agent of biological warfare highlights the need to develop fast and effective methods to detect biologically active ricin. The current “gold standard” for ricin detection is an in vivo mouse bioassay; however, this method is not practical to test on a large number of...

  5. Biological Activity of Recently Discovered Halogenated Marine Natural Products

    PubMed Central

    Gribble, Gordon W.

    2015-01-01

    This review presents the biological activity—antibacterial, antifungal, anti-parasitic, antiviral, antitumor, antiinflammatory, antioxidant, and enzymatic activity—of halogenated marine natural products discovered in the past five years. Newly discovered examples that do not report biological activity are not included. PMID:26133553

  6. Methods of increasing secretion of polypeptides having biological activity

    DOEpatents

    Merino, Sandra

    2013-10-01

    The present invention relates to methods for producing a secreted polypeptide having biological activity, comprising: (a) transforming a fungal host cell with a fusion protein construct encoding a fusion protein, which comprises: (i) a first polynucleotide encoding a signal peptide; (ii) a second polynucleotide encoding at least a catalytic domain of an endoglucanase or a portion thereof; and (iii) a third polynucleotide encoding at least a catalytic domain of a polypeptide having biological activity; wherein the signal peptide and at least the catalytic domain of the endoglucanase increases secretion of the polypeptide having biological activity compared to the absence of at least the catalytic domain of the endoglucanase; (b) cultivating the transformed fungal host cell under conditions suitable for production of the fusion protein; and (c) recovering the fusion protein, a component thereof, or a combination thereof, having biological activity, from the cultivation medium.

  7. Methods of increasing secretion of polypeptides having biological activity

    DOEpatents

    Merino, Sandra

    2014-05-27

    The present invention relates to methods for producing a secreted polypeptide having biological activity, comprising: (a) transforming a fungal host cell with a fusion protein construct encoding a fusion protein, which comprises: (i) a first polynucleotide encoding a signal peptide; (ii) a second polynucleotide encoding at least a catalytic domain of an endoglucanase or a portion thereof; and (iii) a third polynucleotide encoding at least a catalytic domain of a polypeptide having biological activity; wherein the signal peptide and at least the catalytic domain of the endoglucanase increases secretion of the polypeptide having biological activity compared to the absence of at least the catalytic domain of the endoglucanase; (b) cultivating the transformed fungal host cell under conditions suitable for production of the fusion protein; and (c) recovering the fusion protein, a component thereof, or a combination thereof, having biological activity, from the cultivation medium.

  8. Methods of increasing secretion of polypeptides having biological activity

    SciTech Connect

    Merino, Sandra

    2014-10-28

    The present invention relates to methods for producing a secreted polypeptide having biological activity, comprising: (a) transforming a fungal host cell with a fusion protein construct encoding a fusion protein, which comprises: (i) a first polynucleotide encoding a signal peptide; (ii) a second polynucleotide encoding at least a catalytic domain of an endoglucanase or a portion thereof; and (iii) a third polynucleotide encoding at least a catalytic domain of a polypeptide having biological activity; wherein the signal peptide and at least the catalytic domain of the endoglucanase increases secretion of the polypeptide having biological activity compared to the absence of at least the catalytic domain of the endoglucanase; (b) cultivating the transformed fungal host cell under conditions suitable for production of the fusion protein; and (c) recovering the fusion protein, a component thereof, or a combination thereof, having biological activity, from the cultivation medium.

  9. Methods of increasing secretion of polypeptides having biological activity

    SciTech Connect

    Merino, Sandra

    2015-04-14

    The present invention relates to methods for producing a secreted polypeptide having biological activity, comprising: (a) transforming a fungal host cell with a fusion protein construct encoding a fusion protein, which comprises: (i) a first polynucleotide encoding a signal peptide; (ii) a second polynucleotide encoding at least a catalytic domain of an endoglucanase or a portion thereof; and (iii) a third polynucleotide encoding at least a catalytic domain of a polypeptide having biological activity; wherein the signal peptide and at least the catalytic domain of the endoglucanase increases secretion of the polypeptide having biological activity compared to the absence of at least the catalytic domain of the endoglucanase; (b) cultivating the transformed fungal host cell under conditions suitable for production of the fusion protein; and (c) recovering the fusion protein, a component thereof, or a combination thereof, having biological activity, from the cultivation medium.

  10. Multifunctional and biologically active matrices from multicomponent polymeric solutions

    NASA Technical Reports Server (NTRS)

    Kiick, Kristi L. (Inventor); Yamaguchi, Nori (Inventor)

    2010-01-01

    The present invention relates to a biologically active functionalized electrospun matrix to permit immobilization and long-term delivery of biologically active agents. In particular the invention relates to a functionalized polymer matrix comprising a matrix polymer, a compatibilizing polymer and a biomolecule or other small functioning molecule. In certain aspects the electrospun polymer fibers comprise at least one biologically active molecule functionalized with low molecular weight heparin. Examples of active molecules that may be used with the multicomponent polymer of the invention include, for example, a drug, a biopolymer, for example a growth factor, a protein, a peptide, a nucleotide, a polysaccharide, a biological macromolecule or the like. The invention is further directed to the formation of functionalized crosslinked matrices, such as hydrogels, that include at least one functionalized compatibilizing polymer capable of assembly.

  11. Coumarin heterocyclic derivatives: chemical synthesis and biological activity.

    PubMed

    Medina, Fernanda G; Marrero, Joaquín G; Macías-Alonso, Mariana; González, Magdalena C; Córdova-Guerrero, Iván; Teissier García, Ariana G; Osegueda-Robles, Soraya

    2015-09-23

    This review highlights the broad range of science that has arisen from the synthesis of coumarin-linked and fused heterocycle derivatives. Specific topics include their synthesis and biological activity. PMID:26151411

  12. Biological activities of Croton palanostigma Klotzsch

    PubMed Central

    Mota, Eduardo Ferreira; Rosario, Diele Magno; Silva Veiga, Andreza Socorro; Barros Brasil, Davi Do Socorro; Silveira, Fernando Tobias; Dolabela, Maria Fâni

    2016-01-01

    Background: Different species of Croton are used in traditional Amazonian medicine. Among the popular uses are treatment of bacterial diseases, poorly healing wounds and fevers. Objective: This study evaluated the antileishmanial, antiplasmodial and antimicrobial activities of the extracts and diterpenes of Croton palanostigma Klotzsch (Euphorbiaceae). Materials and Methods: Leaves and bark were extracted with dichloromethane and methanol. The bark dichloromethane extract (BDE) was chromatographed on a column, obtaining cordatin and aparisthman. The extracts and diterpenes were assayed thought agar disk diffusion method and their bactericidal or fungicidal effects were evaluated by minimum bactericidal or fungicidal concentration. The antiplasmodial activity was evaluated after 24 and 72 h of exposition. The antileishmanial activity was performed on promastigotes forms of Leishmania amazonensis. Results: The bark methanol extract (BME) and cordatin were not active against any microbial strains tested; BDE and leaves methanol extract (LME) were positive for Pseudomonas aeruginosa and aparisthman was positive for Candida albicans. In the determination of the minimum bactericidal concentration, neither of them were active in the highest concentration tested. The extracts and diterpenes were inactive in Plasmodium falciparum, except the LME in 72 h. Any extract was shown to be active in promastigote forms of L. amazonensis. Conclusion: These results indicate that the BDE and LME did not inhibit the bacterial growth, then they probably had bacteriostatic effect. LME presented activity in P. falciparum. PMID:27041867

  13. Biological activities of Croton palanostigma Klotzsch

    PubMed Central

    Mota, Eduardo Ferreira; Rosario, Diele Magno; Silva Veiga, Andreza Socorro; Brasil, Davi Do Socorro Barros; Silveira, Fernando Tobias; Dolabela, Maria Fâni

    2015-01-01

    Background: Different species of Croton are used in traditional Amazonian medicine. Among the popular uses are treatment of bacterial diseases, poorly healing wounds and fevers. Objective: This study evaluated the antileishmanial, antiplasmodial and antimicrobial activities of the extracts and diterpenes of Croton palanostigma Klotzsch (Euphorbiaceae). Materials and Methods: Leaves and bark were extracted with dichloromethane and methanol. The bark dichloromethane extract (BDE) was chromatographed on a column, obtaining cordatin and aparisthman. The extracts and diterpenes were assayed thought agar disk diffusion method and their bactericidal or fungicidal effects were evaluated by minimum bactericidal or fungicidal concentration. The antiplasmodial activity was evaluated after 24 and 72 h of exposition. The antileishmanial activity was performed on promastigotes forms of Leishmania amazonensis. Results: The bark methanol extract (BME) and cordatin were not active against any microbial strains tested; BDE and leaves methanol extract (LME) were positive for Pseudomonas aeruginosa and aparisthman was positive for Candida albicans. In the determination of the minimum bactericidal concentration, neither of them were active in the highest concentration tested. The extracts and diterpenes were inactive in Plasmodium falciparum, except the LME in 72 h. Any extract was shown to be active in promastigote forms of L. amazonensis. Conclusion: These results indicate that the BDE and LME did not inhibit the bacterial growth, then they probably had bacteriostatic effect. LME presented activity in P. falciparum. PMID:26246738

  14. Binuclear Cu(II) and Co(II) Complexes of Tridentate Heterocyclic Shiff Base Derived from Salicylaldehyde with 4-Aminoantipyrine

    PubMed Central

    Al-Obaidi, Omar Hamad Shihab

    2012-01-01

    New binuclear Co(II) and Co(II) complexes of ONO tridentate heterocyclic Schiff base derived from 4-aminoantipyrine with salicylaldehyde have been synthesized and characterized on the bases of elemental analysis, UV-Vis., FT-IR, and also by aid of molar conductivity measurements, magnetic measurements, and melting points. It has been found that the Schiff bases with Cu(II) or Co(II) ion forming binuclear complexes on (1 : 1) “metal : ligand” stoichiometry. The molar conductance measurements of the complexes in DMSO correspond to be nonelectrolytic nature for all prepared complexes. Distorted octahedral environment is suggested for metal complexes. A theoretical treatment of the formation of complexes in the gas phase was studied, and this was done by using the HyperChem-6 program for the molecular mechanics and semi-empirical calculations. The free ligand and its complexes have been tested for their antibacterial activities against two types of human pathogenic bacteria: the first type (Staphylococcus aureus) is Gram positive and the second type (Escherichia coli) is Gram negative (by using agar well diffusion method). Finally, it was found that compounds show different activity of inhibition on growth of the bacteria. PMID:22611346

  15. Physical activity and biological maturation: a systematic review

    PubMed Central

    Bacil, Eliane Denise Araújo; Mazzardo, Oldemar; Rech, Cassiano Ricardo; Legnani, Rosimeide Francisco dos Santos; de Campos, Wagner

    2015-01-01

    OBJECTIVE: To analyze the association between physical activity (PA) and biological maturation in children and adolescents. DATA SOURCE: We performed a systematic review in April 2013 in the electronic databases of PubMed/MEDLINE, SportDiscus, Web of Science and LILACS without time restrictions. A total of 628 potentially relevant articles were identified and 10 met the inclusion criteria for this review: cross-sectional or longitudinal studies, published in Portuguese, English or Spanish, with schoolchildren aged 9-15 years old of both genders. DATA SYNTHESIS: Despite the heterogeneity of the studies, there was an inverse association between PA and biological maturation. PA decreases with increased biological and chronological age in both genders. Boys tend to be more physically active than girls; however, when controlling for biological age, the gender differences disappear. The association between PA and timing of maturation varies between the genders. Variation in the timing of biological maturation affects the tracking of PA in early adolescent girls. This review suggests that mediators (BMI, depression, low self-esteem, and concerns about body weight) can explain the association between PA and biological maturation. CONCLUSIONS: There is an association between PA and biological maturation. PA decreases with increasing biological age with no differences between genders. As for the timing of biological maturation, this association varies between genders. PMID:25583624

  16. Activated Sludge. Student Manual. Biological Treatment Process Control.

    ERIC Educational Resources Information Center

    Boe, Owen K.; Klopping, Paul H.

    This student manual contains the textual material for a seven-lesson unit on activated sludge. Topic areas addressed in the lessons include: (1) activated sludge concepts and components (including aeration tanks, aeration systems, clarifiers, and sludge pumping systems); (2) activated sludge variations and modes; (3) biological nature of activated…

  17. Biologically active triterpenoids from Cephalaria ambrosioides.

    PubMed

    Pasi, Sofia; Aligiannis, Nektarios; Pratsinis, Harris; Skaltsounis, Alexios-Leandros; Chinou, Ioanna B

    2009-02-01

    The roots of Cephalaria ambrosioides yielded a new triterpene, 6alpha-hydroxyhederagenic acid ( 1), in addition to the known triterpene hederagenic acid ( 2) and four corresponding saponins, leontoside A (or akeboside Stb) ( 3), kalopanax saponin A (or alpha-hederin) ( 4), saponin PG (or sapindoside B) ( 5), and dipsacoside B ( 6). Their structures have been elucidated on the basis of their spectral data (MS, 1 D and 2 D NMR) and by some chemical transformations. The extract and all isolated compounds were evaluated for their antimicrobial, molluscicidal and IN VITRO cytotoxic activities. All compounds showed strong antimicrobial activity (MIC values 1.80 - 2.50 microg/mL), with 5 and 6 exhibiting activities comparable to those of standard antibiotics. Moreover, compounds 3 - 5 were active against all assayed cancer cell lines, whereas compounds 3 and 4 exhibited higher activities against Biomphalaria Glabrata snails, with minimum inhibitory concentrations of 5.4 and 6.2 microg/mL, respectively. PMID:19152225

  18. Biologically active compounds of semi-metals.

    PubMed

    Rezanka, Tomás; Sigler, Karel

    2008-02-01

    Semi-metals (boron, silicon, arsenic and selenium) form organo-metal compounds, some of which are found in nature and affect the physiology of living organisms. They include, e.g., the boron-containing antibiotics aplasmomycin, borophycin, boromycin, and tartrolon or the silicon compounds present in "silicate" bacteria, relatives of the genus Bacillus, which release silicon from aluminosilicates through the secretion of organic acids. Arsenic is incorporated into arsenosugars and arsenobetaines by marine algae and invertebrates, and fungi and bacteria can produce volatile methylated arsenic compounds. Some prokaryotes can use arsenate as a terminal electron acceptor while others can utilize arsenite as an electron donor to generate energy. Selenium is incorporated into selenocysteine that is found in some proteins. Biomethylation of selenide produces methylselenide and dimethylselenide. Selenium analogues of amino acids, antitumor, antibacterial, antifungal, antiviral, anti-infective drugs are often used as analogues of important pharmacological sulfur compounds. Other metalloids, i.e. the rare and toxic tellurium and the radioactive short-lived astatine, have no biological significance. PMID:17991498

  19. Strong DNA deformation required for extremely slow DNA threading intercalation by a binuclear ruthenium complex.

    PubMed

    Almaqwashi, Ali A; Paramanathan, Thayaparan; Lincoln, Per; Rouzina, Ioulia; Westerlund, Fredrik; Williams, Mark C

    2014-10-01

    DNA intercalation by threading is expected to yield high affinity and slow dissociation, properties desirable for DNA-targeted therapeutics. To measure these properties, we utilize single molecule DNA stretching to quantify both the binding affinity and the force-dependent threading intercalation kinetics of the binuclear ruthenium complex Δ,Δ-[μ-bidppz-(phen)4Ru2]4+ (Δ,Δ-P). We measure the DNA elongation at a range of constant stretching forces using optical tweezers, allowing direct characterization of the intercalation kinetics as well as the amount intercalated at equilibrium. Higher forces exponentially facilitate the intercalative binding, leading to a profound decrease in the binding site size that results in one ligand intercalated at almost every DNA base stack. The zero force Δ,Δ-P intercalation Kd is 44 nM, 25-fold stronger than the analogous mono-nuclear ligand (Δ-P). The force-dependent kinetics analysis reveals a mechanism that requires DNA elongation of 0.33 nm for association, relaxation to an equilibrium elongation of 0.19 nm, and an additional elongation of 0.14 nm from the equilibrium state for dissociation. In cells, a molecule with binding properties similar to Δ,Δ-P may rapidly bind DNA destabilized by enzymes during replication or transcription, but upon enzyme dissociation it is predicted to remain intercalated for several hours, thereby interfering with essential biological processes. PMID:25245944

  20. Strong DNA deformation required for extremely slow DNA threading intercalation by a binuclear ruthenium complex

    PubMed Central

    Almaqwashi, Ali A.; Paramanathan, Thayaparan; Lincoln, Per; Rouzina, Ioulia; Westerlund, Fredrik; Williams, Mark C.

    2014-01-01

    DNA intercalation by threading is expected to yield high affinity and slow dissociation, properties desirable for DNA-targeted therapeutics. To measure these properties, we utilize single molecule DNA stretching to quantify both the binding affinity and the force-dependent threading intercalation kinetics of the binuclear ruthenium complex Δ,Δ-[μ‐bidppz‐(phen)4Ru2]4+ (Δ,Δ-P). We measure the DNA elongation at a range of constant stretching forces using optical tweezers, allowing direct characterization of the intercalation kinetics as well as the amount intercalated at equilibrium. Higher forces exponentially facilitate the intercalative binding, leading to a profound decrease in the binding site size that results in one ligand intercalated at almost every DNA base stack. The zero force Δ,Δ-P intercalation Kd is 44 nM, 25-fold stronger than the analogous mono-nuclear ligand (Δ-P). The force-dependent kinetics analysis reveals a mechanism that requires DNA elongation of 0.33 nm for association, relaxation to an equilibrium elongation of 0.19 nm, and an additional elongation of 0.14 nm from the equilibrium state for dissociation. In cells, a molecule with binding properties similar to Δ,Δ-P may rapidly bind DNA destabilized by enzymes during replication or transcription, but upon enzyme dissociation it is predicted to remain intercalated for several hours, thereby interfering with essential biological processes. PMID:25245944

  1. Binuclear Cells in the Lactating Mammary Gland: New Insights on an Old Concept?

    PubMed

    Smith, Gilbert H

    2016-06-01

    In a recent paper (Rios et al. Nat Commun. 7:11400, 2016), it was reported that polyploid cells are frequent in lactating mammary tissues. This phenomenon was observed in mammary tissue sampled from five separate mammalian species. According to that report, these binucleated cells occur late in pregnancy and early in lactation. Unfortunately, this paper did not mention a number of earlier observations and findings that remain pertinent to this day (Banerjee et al. Life sciences Pt 2: Biochemistry, general and molecular biology. 10(15):867-77, 1971; Banerjee MR, Wagner JE. Biochem. Biophys. Res. Commun. 49(2):480-7, 1972). In these classical experiments, the authors demonstrated in vivo that DNA synthesis continued without commensurate cell division during late pregnancy and lactation, and that this DNA synthesis was imperative for functional differentiation of the mammary epithelium. Later studies showed that DNA synthesis was indispensable to the induction of milk protein production in explant cultures of mammary tissue from unprimed, nulliparous mice. This dependence on DNA synthesis in mammary explant cultures stimulated by lactogenic hormones was found to be dispensable following a single pregnancy. The absolute requirement for DNA synthesis in nulliparous mouse mammary explants stimulated to synthesize milk protein in vitro has remained unexplained, as has the need for DNA synthesis prior to the onset of lactation. From a historical perspective, it is more likely that binuclear secretory cells in the lactating mammary gland are a consequence of the DNA synthesis requirement for lactation, rather than an essential element. PMID:27255141

  2. Characterization of Metastable Intermediates Formed in the Reaction Between a Mn(II) Complex and Dioxygen, Including a Crystallographic Structure of a Binuclear Mn(III)-Peroxo Species

    PubMed Central

    Coggins, Michael K.; Sun, Xianru; Kwak, Yeonju; Solomon, Edward I.; Rybak-Akimova, Elena; Kovacs, Julie A.

    2013-01-01

    Transition-metal peroxos have been implicated as key intermediates in a variety of critical biological processes involving O2. Due to their highly reactive nature, very few metal-peroxos have been characterized. The dioxygen chemistry of manganese remains largely unexplored despite the proposed involvement of a binuclear Mn-peroxo, either as a precursor to O2, or derived from O2, in both photosynthetic H2O oxidation and DNA biosynthesis, arguably two of the most fundamental processes of life. Neither of these biological intermediates has been observed. Herein we describe the dioxygen chemistry of coordinatively unsaturated [MnII(SMe2N4(6-MeDPEN))] +(1), and the characterization of intermediates formed en route to a binuclear mono-oxo bridged Mn(III) product {[MnIII(SMe2N4(6-MeDPEN)]2-(μ-O)}2+ (2), the oxo atom of which is derived from 18O2. At low-temperatures, a dioxygen intermediate, [Mn(SMe2N4(6-MeDPEN))(O2)]+ (4), is observed (by stopped-flow) to rapidly and irreversibly form in this reaction (k1(−10 °C)= 3780±180M−1s−1, ΔH1‡ = 26.4±1.7 kJ mol−1, ΔS1‡ = − 75.6±6.8 J mol−1K−1), and then convert more slowly (k2(−10 °C)= 417±3.2 M−1s−1, ΔH2‡ = 47.1±1.4 kJ mol−1, ΔS2‡ = − 15.0±5.7 J mol−1K−1) to a species 3 with isotopically sensitive stretches at νo-o (Δ18O) = 819(47) cm−1, kO–O= 3.02 mdyn/Å, and νMn-O(Δ18O) = 611(25) cm−1 consistent with a peroxo. Intermediate 3 releases approximately 0.5 equiv of H2O2 per Mn ion upon protonation, and the rate of conversion of 4 to 3 is dependent on [Mn(II)] concentration, consistent with the formation of a binuclear Mn-peroxo. This was verified by X-ray crystallography, where the peroxo of {[MnIII(SMe2N4(6-Me-DPEN)]2(trans–μ–1,2–O2)}2+ (3) is shown to be bridging between two Mn(III) ions in an end-on trans-μ-1,2-fashion. This represents the first characterized example of a binuclear Mn(III)-peroxo, and a rare case in which more than one intermediate is observed

  3. Flavonoids and biological activities of Jussiaea repens.

    PubMed

    Marzouk, M S; Soliman, F M; Shehata, I A; Rabee, M; Fawzy, G A

    2007-05-01

    A new acylated avicularin, namely avicularin 2''-(4'''-O-n-pentanoyl)-gallate (1) along with 12 metabolites have been isolated from the ethyl acetate extract of the aerial parts of Jussiaea repens L. (Onagraceae). Their structures were established as trifolin 2''-O-gallate (2), quercetrin (3), guaijaverin (4), reynoutrin (5), juglanin (6), avicularin (7), hyperin (8), trifolin (9), hyperin 2''-O-gallate (10), rutin (11), kaempferol (12) and quercetin (13) on the basis of their chromatographic properties, chemical and spectroscopic evidences. The investigated ethyl acetate extract was found to be non-toxic (LD(50) up to the maximum soluble dose 4 g kg(-1) body wt.) and had significant antioxidant, hepatoprotective, anti-inflammatory and antidiabetic activities. Also some of the isolated flavonoids showed cytotoxic activity against Ehrlich ascitis carcinoma cells. PMID:17487615

  4. Isoxanthohumol--Biologically active hop flavonoid.

    PubMed

    Żołnierczyk, Anna Katarzyna; Mączka, Wanda Krystyna; Grabarczyk, Małgorzata; Wińska, Katarzyna; Woźniak, Edyta; Anioł, Mirosław

    2015-06-01

    Isoxanthohumol (IXN), apart from xanthohumol (XN) and 8-prenylnaringenin (8PN), is one of the most important prenylflavonoids found in hops. Another natural source of this compound is a shrub Sophora flavescens, used in traditional Chinese medicine. Main dietary source of IXN is beer, and the compound is produced from XN during wort boiling. In the human body, the compound is O-demethylated to 8PN, the strongest known phytoestrogen. This process takes place in the liver and in the intestine, where it is mediated by local microflora. It has been reported in some studies that even though beer contains small amounts of hops and its preparations, these compounds may affect the functioning of the human body. IXN exhibits an antiproliferative activity against human cell lines typical for breast cancer (MCF-7), ovarian cancer (A-2780), prostate cancer (DU145 and PC-3), and colon cancer (HT-29 and SW620) cells. It strongly inhibits the activation of the following carcinogens: 2-amino-3-methylimidazol-[4,5-f]quinoline and aflatoxin B1 (AFB1) via human cytochrome P450 (CYP1A2). It also inhibits the production of prostate specific antigen (PSA). IXN significantly reduces the expression of transforming growth factor-β (TGF-β) in the case of invasive breast cancer MDA-MB-231. It interferes with JAK/STAT signaling pathway and inhibits the expression of pro1inflammatory genes in the monoblastic leukemia cell line (MonoMac6). It activates apoptosis in human umbilical vein endothelial cells (HUVEC) and human aortic smooth muscle cells (HASMCs). In addition, IXN shows an antiviral activity towards herpes viruses (HSV1 and HSV2) and bovine viral diarrhea virus (BVDV). PMID:25771121

  5. Synthesis and biological activity of 5-fluorotubercidin.

    PubMed

    Wang, Xiaojing; Seth, Punit P; Ranken, Ray; Swayze, Eric E; Migawa, Michael T

    2004-01-01

    The electrophilic fluorination of 4-chloropyrrolo[2,3-d]pyrimidine (1) was studied culminating a 59% conversion of compound 1 to 4-chloro-5-fluoropyrrolo[2,3-d]pyrimidine (2) using Selectfluor. This transformation proceeded via the 4-chloro-5,6-dihydro-5-fluoro-6-hydroxypyrrolo[2,3-d]pyrimidine (3) in a 9:1 trans:cis ratio. The trans isomer of compound 3 was studied by 1H NMR and 19F NMR, and the 5-H tautomer (4) was observed as another intermediate. A modified Vorbruggen procedure of compound 2 and tetra-O-acetylribose gave 4-chloro-5-fluoro-7-(2,3,5,-tri-O-benzoyl-beta-D-ribofuranosyl)pyrrolo[2,3-d]pyrimidine (6) in a 65% yield. Treatment of compound 6 with ammonia (l) in dioxane gave 5-fluorotubercidin (7). No antibacterial activity was observed. An MTT assay (Promega) against Huh-7 liver cells, normal mouse spleen cells stimulated with Con A (a T-cell mitogen), and normal mouse spleen stimulated with LPS (a B-cell mitogen) showed no significant toxicity. Increased activity of 7 over tubercidin was observed against L-1210 cells and toxicity in fibroblast cells was reduced. PMID:15043144

  6. Biologically active insulin-derived peptides.

    PubMed

    Fawcett, Janet

    2014-06-01

    Insulin has many actions within cells many of which are dependent on the cell type. For example, insulin stimulates glucose uptake in adipose tissue and skeletal muscle but not in liver. In liver glucose influx will increase as insulin stimulates the phosphorylation of glucose and eventual storage in the form of glycogen. Insulin also increases glucose oxidation, decreases glucose production, decreases lipolysis, increases protein synthesis and inhibits protein degradation in addition to others. Many actions have been related to insulin binding to its receptor and subsequent phosphorylation cascades, but insulin action on protein degradation has been shown to be linked to insulin degradation, specifically insulin degradation by the insulin-degrading enzyme (IDE). This activity has been shown to be due to an interaction of IDE with the proteasome, which is responsible for degradation of ubiquitin-tagged proteins. Smaller fragments of insulin that are produced by the action of IDE that do not bind to the insulin receptor show a small effect on protein degradation and a modest effect on mitogenesis. These small fragments do however inhibit lipolysis in a similar manner to insulin. If fragments are larger and can bind to the receptor they have been shown to increase glucose oxidation. Studies show that fragments of the insulin molecule have cellular activity, and that the varied actions of insulin are not completely controlled by insulin binding to the insulin receptor, even though the mechanisms may not be mutually exclusive. PMID:24559166

  7. Biased and unbiased strategies to identify biologically active small molecules.

    PubMed

    Abet, Valentina; Mariani, Angelica; Truscott, Fiona R; Britton, Sébastien; Rodriguez, Raphaël

    2014-08-15

    Small molecules are central players in chemical biology studies. They promote the perturbation of cellular processes underlying diseases and enable the identification of biological targets that can be validated for therapeutic intervention. Small molecules have been shown to accurately tune a single function of pluripotent proteins in a reversible manner with exceptional temporal resolution. The identification of molecular probes and drugs remains a worthy challenge that can be addressed by the use of biased and unbiased strategies. Hypothesis-driven methodologies employs a known biological target to synthesize complementary hits while discovery-driven strategies offer the additional means of identifying previously unanticipated biological targets. This review article provides a general overview of recent synthetic frameworks that gave rise to an impressive arsenal of biologically active small molecules with unprecedented cellular mechanisms. PMID:24811300

  8. Biologically active extracts with kidney affections applications

    NASA Astrophysics Data System (ADS)

    Pascu (Neagu), Mihaela; Pascu, Daniela-Elena; Cozea, Andreea; Bunaciu, Andrei A.; Miron, Alexandra Raluca; Nechifor, Cristina Aurelia

    2015-12-01

    This paper is aimed to select plant materials rich in bioflavonoid compounds, made from herbs known for their application performances in the prevention and therapy of renal diseases, namely kidney stones and urinary infections (renal lithiasis, nephritis, urethritis, cystitis, etc.). This paper presents a comparative study of the medicinal plant extracts composition belonging to Ericaceae-Cranberry (fruit and leaves) - Vaccinium vitis-idaea L. and Bilberry (fruit) - Vaccinium myrtillus L. Concentrated extracts obtained from medicinal plants used in this work were analyzed from structural, morphological and compositional points of view using different techniques: chromatographic methods (HPLC), scanning electronic microscopy, infrared, and UV spectrophotometry, also by using kinetic model. Liquid chromatography was able to identify the specific compounds of the Ericaceae family, present in all three extracts, arbutosid, as well as specific components of each species, mostly from the class of polyphenols. The identification and quantitative determination of the active ingredients from these extracts can give information related to their therapeutic effects.

  9. Biologically active indole and bisindole alkaloids from Tabernaemontana divaricata.

    PubMed

    Kam, Toh-Seok; Pang, Huey-Shen; Lim, Tuck-Meng

    2003-04-21

    The ethanol extract of the leaves of Tabernaemontana divaricata (double flower variety) provided a total of 23 alkaloids, including the new aspidosperma alkaloids, taberhanine, voafinine, N-methylvoafinine, voafinidine, voalenine and the new bisindole alkaloid, conophyllinine in addition to the previously known, biologically active bisindole, conophylline and its congener, conofoline. The structures of the new alkaloids were established by spectroscopic methods. The preparation and characterization of the corresponding quinones of the biologically active bisindoles are also described in relation to a structure-activity study of these compounds with respect to their action in stimulating insulin expression. PMID:12929658

  10. Liposomal packaging generates Wnt protein with in vivo biological activity.

    PubMed

    Morrell, Nathan T; Leucht, Philipp; Zhao, Ludan; Kim, Jae-Beom; ten Berge, Derk; Ponnusamy, Karthik; Carre, A Lyonel; Dudek, Henryk; Zachlederova, Marie; McElhaney, Michael; Brunton, Shirley; Gunzner, Janet; Callow, Marinella; Polakis, Paul; Costa, Mike; Zhang, Xiaoyan M; Helms, Jill A; Nusse, Roel

    2008-01-01

    Wnt signals exercise strong cell-biological and regenerative effects of considerable therapeutic value. There are, however, no specific Wnt agonists and no method for in vivo delivery of purified Wnt proteins. Wnts contain lipid adducts that are required for activity and we exploited this lipophilicity by packaging purified Wnt3a protein into lipid vesicles. Rather than being encapsulated, Wnts are tethered to the liposomal surface, where they enhance and sustain Wnt signaling in vitro. Molecules that effectively antagonize soluble Wnt3a protein but are ineffective against the Wnt3a signal presented by a cell in a paracrine or autocrine manner are also unable to block liposomal Wnt3a activity, suggesting that liposomal packaging mimics the biological state of active Wnts. When delivered subcutaneously, Wnt3a liposomes induce hair follicle neogenesis, demonstrating their robust biological activity in a regenerative context. PMID:18698373

  11. Models Role within Active Learning in Biology. A Case Study

    ERIC Educational Resources Information Center

    Pop-Pacurar, Irina; Tirla, Felicia-Doina

    2009-01-01

    In order to integrate ideas and information creatively, to motivate students and activate their thinking, we have used in Biology classes a series of active methods, among which the methods of critical thinking, which had very good results. Still, in the case of some intuitive, abstract, more difficult topics, such as the cell structure,…

  12. Should soil testing services measure soil biological activity?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Health of agricultural soils depends largely on conservation management to promote soil organic C accumulation. Total soil organic C changes slowly, but active fractions are more dynamic. A key indicator of healthy soil is potential biological activity, which could be measured rapidly with soil te...

  13. Biological activities of derivatized D-glucans: a review.

    PubMed

    Kagimura, Francini Yumi; da Cunha, Mário Antônio A; Barbosa, Aneli M; Dekker, Robert F H; Malfatti, Carlos Ricardo Maneck

    2015-01-01

    D-Glucans have triggered increasing interest in commercial applications in the chemical and pharmaceutical sectors because of their technological properties and biological activities. The glucans are foremost among the polysaccharide groups produced by microorganisms with demonstrated activity in stimulating the immune system, and have potential in treating human disease conditions. Chemical alterations in the structure of D-glucans through derivatization (sulfonylation, carboxymethylation, phosphorylation, acetylation) contributes to their increased solubility that, in turn, can alter their biological activities such as antioxidation and anticoagulation. This review surveys and cites the latest advances on the biological and technological potential of D-glucans following chemical modifications through sulfonylation, carboxymethylation, phosphorylation or acetylation, and discusses the findings of their activities. Several studies suggest that chemically modified d-glucans have potentiated biological activity as anticoagulants, antitumors, antioxidants, and antivirals. This review shows that in-depth future studies on chemically modified glucans with amplified biological effects will be relevant in the biotechnological field because of their potential to prevent and treat numerous human disease conditions and their clinical complications. PMID:25239192

  14. Azaglycomimetics: Natural Occurrence, Biological Activity, and Application

    NASA Astrophysics Data System (ADS)

    Asano, Naoki

    A large number of alkaloids mimicking the structures of monosaccharides or oligosaccharides have been isolated from plants and microorganisms. The sugar mimicking alkaloids with a nitrogen in the ring are called azasugars or iminosugars. Naturally occurring azasugars are classified into five structural classes: polyhydroxylated piperidines, pyrrolidines, indolizidines, pyrrolizidines, and nortropanes. They are easily soluble in water because of their polyhydroxylated structures and inhibit glycosidases because of a structural resemblance to the sugar moiety of the natural substrate. Glycosidases are involved in a wide range of anabolic and catabolic processes, such as digestion, lysosomal catabolism of glycoconjugates, biosynthesis of glycoproteins, and the endoplasmic reticulum (ER) quality control and ER-associated degradation of glycoproteins. Hence, modifying or blocking these processes in vivo by inhibitors is of great interest from a therapeutic point of view. Azasugars are an important class of glycosidase inhibitors and are arousing great interest for instance as antidiabetics, antiobesity drugs, antivirals, and therapeutic agents for some genetic disorders. This review describes the recent studies on isolation, characterization, glycosidase inhibitory activity, and therapeutic application of azaglycomimetics.

  15. [Oregano: properties, composition and biological activity].

    PubMed

    Arcila-Lozano, Cynthia Cristina; Loarca-Piña, Guadalupe; Lecona-Uribe, Salvador; González de Mejía, Elvira

    2004-03-01

    The oregano spice includes various plant species. The most common are the genus Origanum, native of Europe, and the Lippia, native of Mexico. Among the species of Origanum. their most important components are the limonene, gamma-cariofilene, rho-cymenene, canfor, linalol, alpha-pinene, carvacrol and thymol. In the genus Lippia, the same compounds can be found. The oregano composition depends on the specie, climate, altitude, time of recollection and the stage of growth. Some of the properties of this plant's extracts are being currently studied due to the growing interest for substituting synthetic additives commonly found in foods. Oregano has a good antioxidant capacity and also presents antimicrobial activity against pathogenic microorganisms like Salmonella typhimurium, Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis, among others. These are all characteristics of interest for the food industry because they may enhance the safety and stability of foods. There are also some reports regarding the antimutagenic and anticarcinogenic effect of oregano; representing an alternative for the potential treatment and/or prevention of certain chronic ailments, like cancer. PMID:15332363

  16. Phytochemistry and biological activities of Phlomis species.

    PubMed

    Limem-Ben Amor, Ilef; Boubaker, Jihed; Ben Sgaier, Mohamed; Skandrani, Ines; Bhouri, Wissem; Neffati, Aicha; Kilani, Soumaya; Bouhlel, Ines; Ghedira, Kamel; Chekir-Ghedira, Leila

    2009-09-01

    The genus Phlomis L. belongs to the Lamiaceae family and encompasses 100 species native to Turkey, North Africa, Europe and Asia. It is a popular herbal tea enjoyed for its taste and aroma. Phlomis species are used to treat various conditions such as diabetes, gastric ulcer, hemorrhoids, inflammation, and wounds. This review aims to summarize recent research on the phytochemistry and pharmacological properties of the genus Phlomis, with particular emphasis on its ethnobotanical uses. The essential oil of Phomis is composed of four chemotypes dominated by monoterpenes (alpha-pinene, limonene and linalool), sesquiterpenes (germacrene D and beta-caryophyllene), aliphalic compounds (9,12,15-octadecatrienoic acid methyl ester), fatty acids (hexadecanoic acid) and other components (trans-phytol, 9,12,15-octadecatrien-1-ol). Flavonoids, iridoids and phenylethyl alcohol constitute the main compounds isolated from Phlomis extracts. The pharmacological activities of some Phlomis species have been investigated. They are described according to antidiabetic, antinociceptive, antiulcerogenic, protection of the vascular system, anti-inflammatory, antiallergic, anticancer, antimicrobial and antioxidant properties. PMID:19563875

  17. [The Biological Activity of the Sevanol and Its Analogues].

    PubMed

    Osmakov, D I; Koshelev, S G; Belozerova, O A; Kublitski, V S; Andreev, Ya A; Grishin, E V; Kozlov, S A

    2015-01-01

    Previously, from the plant Thymus armeniacus a new lignan sevanol was isolated, it's structure was elucidated and was shown that it effectively inhibits the acid-sensing channel ASIC3 and also exhibits a pronounced analgesic and anti-inflammatory effect. In this work biological activity of the sevanol analog obtained by chemical synthesis from simple precursors, the stereoisomer of sevanol and a precursor molecule represents a half of sevanol was measured in electrophysiological experiments on human ASIC3 channels expressed in Xenopus laevis oocytes. Measured inhibitory activity of a synthetic analogue coincided with the activity ofthe natural molecule. Stereoisomer showed inhibitory activity drop by about a third part, and the precursor molecule showed much less significant activity. In result the significance of functional groups and a spatial configuration of sevanol in order to biological activity was shown that is important to take into account for the optimal synthesis design as well as for new drugs development on its base. PMID:26762099

  18. Synthesis and biological evaluation of optically active Ki16425.

    PubMed

    Sato, Takanao; Sugimoto, Kenji; Inoue, Asuka; Okudaira, Shinichi; Aoki, Junken; Tokuyama, Hidetoshi

    2012-07-01

    An enantionselective synthesis of both enantiomers of Ki16425, which possesses selective LPA antagonistic activity, was achieved. The isoxazole core was constructed by a 1,3-dipolar cycloaddition of nitrile oxide with alkyne and condensation with the optically active α-phenethyl alcohol segment, which was prepared by an enantioselective reduction of arylmethylketone. Biological evaluation of both enantiomers of Ki16425 revealed that the (R)-isomer showed much higher antagonistic activity for LPA(1) and LPA(3) receptors. PMID:22658556

  19. Binuclear complexes of Ni(I) from 4-terphenyldithiophenol.

    PubMed

    Koch, Felix; Schubert, Hartmut; Sirsch, Peter; Berkefeld, Andreas

    2015-08-01

    Binuclear complexes of Ni(i) have been prepared from a 4-terphenyldithiophenol ligand. Steric effects were found to determine the formation of coordination isomeric structures that differ in the nature of metal-to-ligand bonding. Coordination of spatially demanding phosphine ligands PR3, R = C6H6, C6H11, at nickel sites results in a butterfly shaped thiolate-bridged Ni2(μ-S)2 motif. For smaller PMe3, the central π-system of the 4-terphenyl backbone adopts a bis-allyl like μ-syn-η(3):η(3)-C6H4 structure due to significant d-π* Ni(i)-to-ligand charge transfer. Delocalisation indices δ(Ni-Ni) derived from DFT calculations provide a metric to assess the strength of electronic coupling of the Ni sites based on solid state structural data, and indicated less strong electronic coupling for the bis-allyl like structure with δ(Ni-Ni) = 0.225 as compared to 0.548 for the Ni2(μ-S)2 structural motif. A qualitative reactivity study toward CNCH3 as an auxiliary ligand has provided the first insight into the chemical properties of the bimetallic complexes presented. PMID:26130424

  20. Biological Activity of Aminophosphonic Acids and Their Short Peptides

    NASA Astrophysics Data System (ADS)

    Lejczak, Barbara; Kafarski, Pawel

    The biological activity and natural occurrence of the aminophosphonic acids were described half a century ago. Since then the chemistry and biology of this class of compounds have developed into the separate field of phosphorus chemistry. Today it is well acknowledged that these compounds possess a wide variety of promising, and in some cases commercially useful, physiological activities. Thus, they have found applications ranging from agrochemical (with the herbicides glyphosate and bialaphos being the most prominent examples) to medicinal (with the potent antihypertensive fosinopril and antiosteoporetic bisphosphonates being examples).

  1. Teaching Systems Biology: An Active-learning Approach

    PubMed Central

    2005-01-01

    With genomics well established in modern molecular biology, recent studies have sought to further the discipline by integrating complementary methodologies into a holistic depiction of the molecular mechanisms underpinning cell function. This genomic subdiscipline, loosely termed “systems biology,” presents the biology educator with both opportunities and obstacles: The benefit of exposing students to this cutting-edge scientific methodology is manifest, yet how does one convey the breadth and advantage of systems biology while still engaging the student? Here, I describe an active-learning approach to the presentation of systems biology. In graduate classes at the University of Michigan, Ann Arbor, I divided students into small groups and asked each group to interpret a sample data set (e.g., microarray data, two-hybrid data, homology-search results) describing a hypothetical signaling pathway. Mimicking realistic experimental results, each data set revealed a portion of this pathway; however, students were only able to reconstruct the full pathway by integrating all data sets, thereby exemplifying the utility in a systems biology approach. Student response to this cooperative exercise was extremely positive. In total, this approach provides an effective introduction to systems biology appropriate for students at both the undergraduate and graduate levels. PMID:16341259

  2. The biological activity of structurally defined inositol glycans

    PubMed Central

    Goel, Meenakshi; Azev, Viatcheslav N; d’Alarcao, Marc

    2009-01-01

    Background The inositol glycans (IGs) are glycolipid-derived carbohydrates produced by insulin-sensitive cells in response to insulin treatment. IGs exhibit an array of insulin-like activities including stimulation of lipogenesis, glucose transport and glycogen synthesis, suggesting that they may be involved in insulin signal transduction. However, because the natural IGs are structurally heterogeneous and difficult to purify to homogeneity, an understanding of the relationship between structure and biological activity has relied principally on synthetic IGs of defined structure. Discussion This article briefly describes what is known about the role of IGs in signal transduction and reviews the specific biological activities of the structurally defined IGs synthesized and tested to date. Conclusion A pharmacophore for IG activity begins to emerge from the reviewed data and the structural elements necessary for activity are summarized. PMID:20390053

  3. Reactivity of Binuclear Tantalum Clusters on Silica: Characterization by Transient Time-Resolved Spectroscopy

    SciTech Connect

    Nemana, Sailendra; Sun, Junming; Gates, Bruce C.

    2008-05-08

    Binuclear tantalum clusters were synthesized from Ta(CH{sub 2}Ph){sub 5} (Ph is phenyl) on the surface of nonporous SiO{sub 2} (Aerosil), and their reactions with H{sub 2}, D{sub 2}, and ethylene were characterized by time-resolved infrared (IR), extended X-ray absorption fine structure (EXAFS), and X-ray absorption near edge spectroscopies. The EXAFS data indicate the formation in H{sub 2} of clusters with a Ta-Ta coordination number of approximately 1 and a bonding distance of 2.74 {angstrom}. Reactions of the supported clusters with D{sub 2} and H{sub 2} facilitate the interconversion of O-H and O-D groups on the SiO{sub 2} surface. Reaction of these clusters with ethylene led to their rapid fragmentation to give mononuclear tantalum complexes, as the tantalum was oxidized and new ligands formed, suggested by IR spectra to be ethyl. The results demonstrate a rough analogy between the chemistry of tantalum clusters on the SiO{sub 2} surface and their chemistry in solution. Because alkenes are suggested intermediates in the catalytic disproportionation of alkanes on supported tantalum, our results indicate how these intermediates might influence the nature of the catalytically active species.

  4. Pyrolyzed binuclear-cobalt-phthalocyanine as electrocatalyst for oxygen reduction reaction in microbial fuel cells.

    PubMed

    Li, Baitao; Wang, Mian; Zhou, Xiuxiu; Wang, Xiujun; Liu, Bingchuan; Li, Baikun

    2015-10-01

    A novel platinum (Pt)-free cathodic materials binuclear-cobalt-phthalocyanine (Bi-CoPc) pyrolyzed at different temperatures (300-1000 °C) were examined as the oxygen reduction reaction (ORR) catalysts, and compared with unpyrolyzed Bi-CoPc/C and Pt cathode in single chamber microbial fuel cells (SCMFCs). The results showed that the pyrolysis process increased the nitrogen abundance on Bi-CoPc and changed the nitrogen types. The Bi-CoPc pyrolyzed at 800 °C contained a significant amount of pyrrolic-N, and exhibited a high electrochemical catalytic activity. The power density and current density increased with temperature: Bi-CoPc/C-800 > Bi-CoPc/C-1000 > Bi-CoPc/C-600 > Bi-CoPc/C-300 > Bi-CoPc/C. The SCMFC with Bi-CoPc/C-800 cathode had a maximum power density of 604 mW m(-2). The low cost Bi-CoPc compounds developed in this study showed a potential in air-breathing MFC systems, with the proper pyrolysis temperature being chosen. PMID:26142820

  5. Synthesis and biological activity of tetralone abscisic acid analogues.

    PubMed

    Nyangulu, James M; Nelson, Ken M; Rose, Patricia A; Gai, Yuanzhu; Loewen, Mary; Lougheed, Brenda; Quail, J Wilson; Cutler, Adrian J; Abrams, Suzanne R

    2006-04-01

    Bicyclic analogues of the plant hormone abscisic acid (ABA) were designed to incorporate the structural elements and functional groups of the parent molecule that are required for biological activity. The resulting tetralone analogues were predicted to have enhanced biological activity in plants, in part because oxidized products would not cyclize to forms corresponding to the inactive catabolite phaseic acid. The tetralone analogues were synthesized in seven steps from 1-tetralone and a range of analogues were accessible through a second route starting with 2-methyl-1-naphthol. Tetralone ABA 8 was found to have greater activity than ABA in two bioassays. The absolute configuration of (+)-8 was established by X-ray crystallography of a RAMP hydrazone derivative. The hydroxymethyl compounds 10 and 11, analogues for studying the roles of 8- and 9-hydroxy ABA 3 and 6, were also synthesized and found to be active. PMID:16557330

  6. On the biological activity of drug molecules: Busulfan and nabumetone

    NASA Astrophysics Data System (ADS)

    Novak, Igor; Kovač, Branka

    2010-10-01

    The electronic structures of drug molecules busulfan (BSU) and nabumetone (NAB) have been investigated by HeI and HeII UV photoelectron spectroscopy (UPS), quantum chemical calculations and virtual docking studies. Their biological activities are discussed in the framework of their electronic and molecular structures, reactivity and drug-enzyme binding.

  7. Solar Energy Education. Renewable energy activities for biology

    SciTech Connect

    Not Available

    1982-01-01

    An instructional aid for teachers is presented that will allow biology students the opportunity to learn about renewable energy sources. Some of the school activities include using leaves as collectors of solar energy, solar energy stored in wood, and a fuel value test for green and dry woods. A study of organic wastes as a source of fuel is included. (BCS)

  8. BIOLOGICAL ACTIVITY AND POTENTIAL REMEDIATION INVOLVING GEOTEXTILE LANDFILL LEACHATE FILTERS

    EPA Science Inventory

    This paper presents the results of a biological growth study in geotextile filters used in landfill leachate collection systems. fter reviewing the first year's activity, a completely new experimental approach has been taken. sing 100 mm diameter columns for the experimental incu...

  9. Modeling Radial Holoblastic Cleavage: A Laboratory Activity for Developmental Biology.

    ERIC Educational Resources Information Center

    Ellis, Linda K.

    2000-01-01

    Introduces a laboratory activity designed for an undergraduate developmental biology course. Uses Play-Doh (plastic modeling clay) to build a multicellular embryo in order to provide a 3-D demonstration of cleavage. Includes notes for the instructor and student directions. (YDS)

  10. Students' Learning Activities While Studying Biological Process Diagrams

    ERIC Educational Resources Information Center

    Kragten, Marco; Admiraal, Wilfried; Rijlaarsdam, Gert

    2015-01-01

    Process diagrams describe how a system functions (e.g. photosynthesis) and are an important type of representation in Biology education. In the present study, we examined students' learning activities while studying process diagrams, related to their resulting comprehension of these diagrams. Each student completed three learning tasks. Verbal…

  11. BIOLOGICALLY ENHANCED OXYGEN TRANSFER IN THE ACTIVATED SLUDGE PROCESS (JOURNAL)

    EPA Science Inventory

    Biologically enhanced oxgyen transfer has been a hypothesis to explain observed oxygen transfer rates in activated sludge systems that were well above that predicted from aerator clean-water testing. The enhanced oxygen transfer rates were based on tests using BOD bottle oxygen ...

  12. Synthesis and biological activity of enantiomeric pairs of phosphosulfonate herbicides.

    PubMed

    Spangler, L A; Mikolajczyk, M; Burdge, E L; Kielbasiński, P; Smith, H C; Lyzwa, P; Fisher, J D; Omelańczuk, J

    1999-01-01

    The phosphosulfonates are a new class of soil-active herbicides which control a variety of annual grass and broadleaf weeds. Chirality at the phosphorus atom afforded the opportunity to explore stereospecific requirements for herbicidal activity. Chiral (hydroxymethyl)phosphinate intermediates were enzymatically resolved (Pseudomonas fluorescens lipase) from the racemic mixtures and then used to prepare two pairs of enantiomeric phosphosulfonates. Biological testing of the enantiomeric phosphosulfonate herbicides demonstrated that, in each case, the herbicidal activity was attributed to the (+) enantiomer and that the (+) enantiomer is more active than the racemate. PMID:10563892

  13. Chemical and structural features influencing the biological activity of curcumin.

    PubMed

    Priyadarsini, K Indira

    2013-01-01

    Curcumin, a polyphenolic natural product, exhibits therapeutic activity against a number of diseases, attributed mainly to its chemical structure and unique physical, chemical, and biological properties. It is a diferuloyl methane molecule [1,7-bis (4-hydroxy-3- methoxyphenyl)-1,6-heptadiene-3,5-dione)] containing two ferulic acid residues joined by a methylene bridge. It has three important functionalities: an aromatic o-methoxy phenolic group, α, β-unsaturated β-diketo moiety and a seven carbon linker. Extensive research in the last two decades has provided evidence for the role of these different functional groups in its crucial biological activities. A few highlights of chemical structural features associated with the biological activity of curcumin are: The o-methoxyphenol group and methylenic hydrogen are responsible for the antioxidant activity of curcumin, and curcumin donates an electron/ hydrogen atom to reactive oxygen species. Curcumin interacts with a number of biomolecules through non-covalent and covalent binding. The hydrogen bonding and hydrophobicity of curcumin, arising from the aromatic and tautomeric structures along with the flexibility of the linker group are responsible for the non-covalent interactions. The α, β-unsaturated β-diketone moiety covalently interacts with protein thiols, through Michael reaction. The β-diketo group forms chelates with transition metals, there by reducing the metal induced toxicity and some of the metal complexes exhibit improved antioxidant activity as enzyme mimics. New analogues with improved activity are being developed with modifications on specific functional groups of curcumin. The physico-chemical and structural features associated with some of the biological activities of curcumin and important analogues are summarized in this article. PMID:23116315

  14. Using ILP to Identify Pathway Activation Patterns in Systems Biology

    PubMed Central

    Neaves, Samuel R; Millard, Louise A C; Tsoka, Sophia

    2016-01-01

    We show a logical aggregation method that, combined with propositionalization methods, can construct novel structured biological features from gene expression data. We do this to gain understanding of pathway mechanisms, for instance, those associated with a particular disease. We illustrate this method on the task of distinguishing between two types of lung cancer; Squamous Cell Carcinoma (SCC) and Adenocarcinoma (AC). We identify pathway activation patterns in pathways previously implicated in the development of cancers. Our method identified a model with comparable predictive performance to the winning algorithm of a recent challenge, while providing biologically relevant explanations that may be useful to a biologist. PMID:27478883

  15. Stereochemical Assignment of Strigolactone Analogues Confirms Their Selective Biological Activity.

    PubMed

    Artuso, Emma; Ghibaudi, Elena; Lace, Beatrice; Marabello, Domenica; Vinciguerra, Daniele; Lombardi, Chiara; Koltai, Hinanit; Kapulnik, Yoram; Novero, Mara; Occhiato, Ernesto G; Scarpi, Dina; Parisotto, Stefano; Deagostino, Annamaria; Venturello, Paolo; Mayzlish-Gati, Einav; Bier, Ariel; Prandi, Cristina

    2015-11-25

    Strigolactones (SLs) are new plant hormones with various developmental functions. They are also soil signaling chemicals that are required for establishing beneficial mycorrhizal plant/fungus symbiosis. In addition, SLs play an essential role in inducing seed germination in root-parasitic weeds, which are one of the seven most serious biological threats to food security. There are around 20 natural SLs that are produced by plants in very low quantities. Therefore, most of the knowledge on SL signal transduction and associated molecular events is based on the application of synthetic analogues. Stereochemistry plays a crucial role in the structure-activity relationship of SLs, as compounds with an unnatural D-ring configuration may induce biological effects that are unrelated to SLs. We have synthesized a series of strigolactone analogues, whose absolute configuration has been elucidated and related with their biological activity, thus confirming the high specificity of the response. Analogues bearing the R-configured butenolide moiety showed enhanced biological activity, which highlights the importance of this stereochemical motif. PMID:26502774

  16. Similar Biological Activities of Two Isostructural Ruthenium and Osmium Complexes

    SciTech Connect

    Maksimoska,J.; Williams, D.; Atilla-Gokcumen, G.; Smalley, K.; Carroll, P.; Webster, R.; Filippakopoulos, P.; Knapp, S.; Herlyn, M.; Meggers, E.

    2008-01-01

    In this study, we probe and verify the concept of designing unreactive bioactive metal complexes, in which the metal possesses a purely structural function, by investigating the consequences of replacing ruthenium in a bioactive half-sandwich kinase inhibitor scaffold by its heavier congener osmium. The two isostructural complexes are compared with respect to their anticancer properties in 1205?Lu melanoma cells, activation of the Wnt signaling pathway, IC50 values against the protein kinases GSK-3? and Pim-1, and binding modes to the protein kinase Pim-1 by protein crystallography. It was found that the two congeners display almost indistinguishable biological activities, which can be explained by their nearly identical three-dimensional structures and their identical mode of action as protein kinase inhibitors. This is a unique example in which the replacement of a metal in an anticancer scaffold by its heavier homologue does not alter its biological activity.

  17. Biological Activities of Phenolic Compounds Present in Virgin Olive Oil

    PubMed Central

    Cicerale, Sara; Lucas, Lisa; Keast, Russell

    2010-01-01

    The Mediterranean diet is associated with a lower incidence of atherosclerosis, cardiovascular disease, neurodegenerative diseases and certain types of cancer. The apparent health benefits have been partially ascribed to the dietary consumption of virgin olive oil by Mediterranean populations. Much research has focused on the biologically active phenolic compounds naturally present in virgin olive oils to aid in explaining reduced mortality and morbidity experienced by people consuming a traditional Mediterranean diet. Studies (human, animal, in vivo and in vitro) have demonstrated that olive oil phenolic compounds have positive effects on certain physiological parameters, such as plasma lipoproteins, oxidative damage, inflammatory markers, platelet and cellular function, antimicrobial activity and bone health. This paper summarizes current knowledge on the bioavailability and biological activities of olive oil phenolic compounds. PMID:20386648

  18. Synthesis and Biological Activities of Oxadiazole Derivatives: A Review.

    PubMed

    Vaidya, Ankur; Jain, Shweta; Jain, Priyanka; Jain, Prachi; Tiwari, Nidhi; Jain, Roshni; Jain, Rashi; Jain, Abhishek K; Agrawal, Ram K

    2016-01-01

    Recently, there has been wide interest in compounds containing the oxadiazole scaffold because of their unique chemical structure and their broad spectrum of biological properties. This review provides readers with an overview of the main synthetic methodologies for oxadiazoles and of their broad spectrum of pharmacological activities such as, anti-microbial, anti-fungal activity, antiviral, anti-tubercular, anti-inflammatory, anti-convulsant, anti-angiogenic, anti-proliferative, analgesic, anti-oedema and in alzheimer activity, which were reported over the past years. PMID:26864552

  19. Humic substances biological activity at the plant-soil interface

    PubMed Central

    Trevisan, Sara; Francioso, Ornella; Nardi, Serenella

    2010-01-01

    Humic substances (HS) represent the organic material mainly widespread in nature. HS have positive effects on plant physiology by improving soil structure and fertility and by influencing nutrient uptake and root architecture. The biochemical and molecular mechanisms underlying these events are only partially known. HS have been shown to contain auxin and an “auxin-like” activity of humic substances has been proposed, but support to this hypothesis is fragmentary. In this review article, we are giving an overview of available data concerning molecular structures and biological activities of humic substances, with special emphasis on their hormone-like activities. PMID:20495384

  20. Biological Ice Nucleation Activity in Cloud Water (Invited)

    NASA Astrophysics Data System (ADS)

    Delort, A.

    2013-12-01

    Ice nucleation active (INA) biological particles, in particular microorganisms, were studied in cloud water. Twelve cloud samples were collected over a period of 16 months from the puy de Dôme summit (1465 m, France) using sterile cloud droplet impactors. The samples were characterized through biological (cultures, cell counts) and physico-chemical measurements (pH, ion concentrations, carbon content...), and biological ice nuclei were investigated by droplet-freezing assays from -3°C to -13°C. The concentration of total INA particles within this temperature range typically varied from ~1 to ~100 per mL of cloud water; the concentrations of biological IN were several orders of magnitude higher than the values previously reported for precipitations. At -12°C, at least 76% of the IN were biological in origin, i.e. they were inactivated by heating at 95°C, and at temperatures above -8°C only biological material could induce ice. By culture, 44 Pseudomonas-like strains of bacteria were isolated from cloud water samples; 16% of them were found INA at the temperature of -8°C and they were identified as Pseudomonas syringae, Xanthomonas sp. and Pseudoxanthomonas sp.. Two strains induced freezing at as warm as -2°C, positioning them among the most active ice nucleators described so far. We estimated that, in average, 0.18% and more than 1%.of the bacterial cells present in clouds (~104 mL-1) are INA at the temperatures of -8°C and -12°C, respectively.

  1. Models to support active sensing of biological aerosol clouds

    NASA Astrophysics Data System (ADS)

    Brown, Andrea M.; Kalter, Jeffrey M.; Corson, Elizabeth C.; Chaudhry, Zahra; Boggs, Nathan T.; Brown, David M.; Thomas, Michael E.; Carter, Christopher C.

    2013-05-01

    Elastic backscatter LIght Detection And Ranging (LIDAR) is a promising approach for stand-off detection of biological aerosol clouds. Comprehensive models that explain the scattering behavior from the aerosol cloud are needed to understand and predict the scattering signatures of biological aerosols under varying atmospheric conditions and against different aerosol backgrounds. Elastic signatures are dependent on many parameters of the aerosol cloud, with two major components being the size distribution and refractive index of the aerosols. The Johns Hopkins University Applied Physics Laboratory (JHU/APL) has been in a unique position to measure the size distributions of released biological simulant clouds using a wide assortment of aerosol characterization systems that are available on the commercial market. In conjunction with the size distribution measurements, JHU/APL has also been making a dedicated effort to properly measure the refractive indices of the released materials using a thin-film absorption technique and laboratory characterization of the released materials. Intimate knowledge of the size distributions and refractive indices of the biological aerosols provides JHU/APL with powerful tools to build elastic scattering models, with the purpose of understanding, and ultimately, predicting the active signatures of biological clouds.

  2. Point-light biological motion perception activates human premotor cortex.

    PubMed

    Saygin, Ayse Pinar; Wilson, Stephen M; Hagler, Donald J; Bates, Elizabeth; Sereno, Martin I

    2004-07-01

    Motion cues can be surprisingly powerful in defining objects and events. Specifically, a handful of point-lights attached to the joints of a human actor will evoke a vivid percept of action when the body is in motion. The perception of point-light biological motion activates posterior cortical areas of the brain. On the other hand, observation of others' actions is known to also evoke activity in motor and premotor areas in frontal cortex. In the present study, we investigated whether point-light biological motion animations would lead to activity in frontal cortex as well. We performed a human functional magnetic resonance imaging study on a high-field-strength magnet and used a number of methods to increase signal, as well as cortical surface-based analysis methods. Areas that responded selectively to point-light biological motion were found in lateral and inferior temporal cortex and in inferior frontal cortex. The robust responses we observed in frontal areas indicate that these stimuli can also recruit action observation networks, although they are very simplified and characterize actions by motion cues alone. The finding that even point-light animations evoke activity in frontal regions suggests that the motor system of the observer may be recruited to "fill in" these simplified displays. PMID:15240810

  3. Biological markers of macrophage activation: applications for fish phagocytes.

    PubMed Central

    Enane, N A; Frenkel, K; O'Connor, J M; Squibb, K S; Zelikoff, J T

    1993-01-01

    The immune defence mechanisms of fish seem to be related and similarly competent to those of mammals. Because of this, there is an increased interest in the immune responses of fish as models for higher vertebrates in immunological/immunotoxicological studies. Macrophages (M phi), phagocytic cells of the mammalian and teleost immune system which reside in tissues, represent a quiescent population of cells. However, upon stimulation, alterations in the physiology of these resident M phi occur which can be defined in terms of activation. This study was undertaken to determine whether biological markers used to assess mammalian M phi activation are applicable for use with fish M phi. Cells were recovered from the peritoneal cavity of non-injected and Aeromonas salmonicida-injected fish, and differences between resident and elicited M phi were evaluated with respect to protein content, phagocytic competence, enzyme activities and hydrogen peroxide production. Results demonstrate that biological markers used to assess mammalian M phi activation, with the exception of acid phosphatase activity, can be used to characterize the activation state of trout M phi, and that the activation process in both fish and mammals may occur by similar mechanism(s). PMID:8244466

  4. Biological activities of xanthatin from Xanthium strumarium leaves.

    PubMed

    Nibret, Endalkachew; Youns, Mahamoud; Krauth-Siegel, R Luise; Wink, Michael

    2011-12-01

    The objective of the present work was to evaluate the biological activities of the major bioactive compound, xanthatin, and other compounds from Xanthium strumarium (Asteraceae) leaves. Inhibition of bloodstream forms of Trypanosoma brucei brucei and leukaemia HL-60 cell proliferation was assessed using resazurin as a vital stain. Xanthatin was found to be the major and most active compound against T. b. brucei with an IC(50) value of 2.63 µg/mL and a selectivity index of 20. The possible mode of action of xanthatin was further evaluated. Xanthatin showed antiinflammatory activity by inhibiting both PGE(2) synthesis (24% inhibition) and 5-lipoxygenase activity (92% inhibition) at concentrations of 100 µg/mL and 97 µg/mL, respectively. Xanthatin exhibited weak irreversible inhibition of parasite specific trypanothione reductase. Unlike xanthatin, diminazene aceturate and ethidium bromide showed strong DNA intercalation with IC(50) values of 26.04 µg/mL and 44.70 µg/mL, respectively. Substantial induction of caspase 3/7 activity in MIA PaCa-2 cells was observed after 6 h of treatment with 100 µg/mL of xanthatin. All these data taken together suggest that xanthatin exerts its biological activity by inducing apoptosis and inhibiting both PGE(2) synthesis and 5-lipoxygenase activity thereby avoiding unwanted inflammation commonly observed in diseases such as trypanosomiasis. PMID:21953905

  5. Biological activities and medicinal properties of Gokhru (Pedalium murex L.)

    PubMed Central

    Rajashekar, V; Rao, E Upender; P, Srinivas

    2012-01-01

    Bada Gokhru (Pedalium murex L.) is perhaps the most useful traditional medicinal plant in India. Each part of the neem tree has some medicinal property and is thus commercially exploitable. During the last five decades, apart from the chemistry of the Pedalium murex compounds, considerable progress has been achieved regarding the biological activity and medicinal applications of this plant. It is now considered as a valuable source of unique natural products for development of medicines against various diseases and also for the development of industrial products. This review gives a bird's eye view mainly on the biological activities of some of this compounds isolated, pharmacological actions of the extracts, clinical studies and plausible medicinal applications of gokharu along with their safety evaluation. PMID:23569975

  6. Milk kefir: composition, microbial cultures, biological activities, and related products

    PubMed Central

    Prado, Maria R.; Blandón, Lina Marcela; Vandenberghe, Luciana P. S.; Rodrigues, Cristine; Castro, Guillermo R.; Thomaz-Soccol, Vanete; Soccol, Carlos R.

    2015-01-01

    In recent years, there has been a strong focus on beneficial foods with probiotic microorganisms and functional organic substances. In this context, there is an increasing interest in the commercial use of kefir, since it can be marketed as a natural beverage that has health promoting bacteria. There are numerous commercially available kefir based-products. Kefir may act as a matrix in the effective delivery of probiotic microorganisms in different types of products. Also, the presence of kefir’s exopolysaccharides, known as kefiran, which has biological activity, certainly adds value to products. Kefiran can also be used separately in other food products and as a coating film for various food and pharmaceutical products. This article aims to update the information about kefir and its microbiological composition, biological activity of the kefir’s microflora and the importance of kefiran as a beneficial health substance. PMID:26579086

  7. Marine Omega-3 Phospholipids: Metabolism and Biological Activities

    PubMed Central

    Burri, Lena; Hoem, Nils; Banni, Sebastiano; Berge, Kjetil

    2012-01-01

    The biological activities of omega-3 fatty acids (n-3 FAs) have been under extensive study for several decades. However, not much attention has been paid to differences of dietary forms, such as triglycerides (TGs) versus ethyl esters or phospholipids (PLs). New innovative marine raw materials, like krill and fish by-products, present n-3 FAs mainly in the PL form. With their increasing availability, new evidence has emerged on n-3 PL biological activities and differences to n-3 TGs. In this review, we describe the recently discovered nutritional properties of n-3 PLs on different parameters of metabolic syndrome and highlight their different metabolic bioavailability in comparison to other dietary forms of n-3 FAs. PMID:23203133

  8. Recent insight into the biological activities of synthetic xanthone derivatives.

    PubMed

    Shagufta; Ahmad, Irshad

    2016-06-30

    Xanthones are a class of oxygen containing heterocyclic compounds with a broad range of biological activities, and they have prominent significance in the field of medicinal chemistry. Xanthone is an attractive scaffold for the design and development of new drugs due to its promising biological activities, primarily as anticancer, antimalarial, antimicrobial, anti-HIV, anticonvulsant, anticholinesterase, antioxidant, anti-inflammatory, and as inhibitors of several enzymes like α-glycosidase, topoisomerase, protein kinase, aromatase, etc. In this review, we have compiled and discussed recent developments on the pharmacological profile of synthetic xanthone derivatives for different therapeutic targets. The review highlights the therapeutic significance of xanthones and offers support in the development of new xanthone derivatives as therapeutic agents. PMID:27111599

  9. Removal of Biologically Active Organic Contaminants using Atomic Oxygen

    NASA Technical Reports Server (NTRS)

    Banks, Bruce A. (Inventor); Banks, Michael A. (Inventor); Banks, Eric B. (Inventor)

    2003-01-01

    Biomedical devices that are to come into contact with living tissue, such as prosthetic and other implants for the human body and the containers used to store and transport them, are together cleaned of non-living, but biologically active organic materials, including endotoxins such as lipopolysaccharides, and assembled into a hermetically sealed package without recontamination. This is achieved by cleaning both the device and package components together in an apparatus, which includes a hermetically sealed chamber, in which they are contacted with atomic oxygen which biocleans them, by oxidizing the biologically active organic materials. The apparatus also includes means for manipulating the device and container and hermetically sealing the cleaned device into the cleaned container to form the package. A calibrated witness coupon visually indicates whether or not the device and container have received enough exposure to the atomic oxygen to have removed the organic materials from their surfaces. Gamma radiation is then used to sterilize the device in the sealed container.

  10. Biological activities and medicinal properties of Cajanus cajan (L) Millsp.

    PubMed Central

    Pal, Dilipkumar; Mishra, Pragya; Sachan, Neetu; Ghosh, Ashoke K.

    2011-01-01

    Cajanus cajan (L) Millsp. (Sanskrit: Adhaki, Hindi: Arhar, English: Pigeon pea, Bengali: Tur) (family: Fabaceae) is the most important grain legume crop of rain-fed agriculture in semi-arid tropics. It is both a food crop and a cover/forage crop with high levels of proteins and important amino acids like methionine, lysine and tryptophan. During the last few decades extensive studies have been carried out regarding the chemistry of C. cajan and considerable progress has been achieved regarding its biological activities and medicinal applications. This review article gives an overview on the biological activities of the compounds isolated, pharmacological actions and clinical studies of C. cajan extracts apart from its general details. PMID:22247887

  11. Biological activities and medicinal properties of Cajanus cajan (L) Millsp.

    PubMed

    Pal, Dilipkumar; Mishra, Pragya; Sachan, Neetu; Ghosh, Ashoke K

    2011-10-01

    Cajanus cajan (L) Millsp. (Sanskrit: Adhaki, Hindi: Arhar, English: Pigeon pea, Bengali: Tur) (family: Fabaceae) is the most important grain legume crop of rain-fed agriculture in semi-arid tropics. It is both a food crop and a cover/forage crop with high levels of proteins and important amino acids like methionine, lysine and tryptophan. During the last few decades extensive studies have been carried out regarding the chemistry of C. cajan and considerable progress has been achieved regarding its biological activities and medicinal applications. This review article gives an overview on the biological activities of the compounds isolated, pharmacological actions and clinical studies of C. cajan extracts apart from its general details. PMID:22247887

  12. Current status of pyrazole and its biological activities

    PubMed Central

    Naim, Mohd Javed; Alam, Ozair; Nawaz, Farah; Alam, Md. Jahangir; Alam, Perwaiz

    2016-01-01

    Pyrazole are potent medicinal scaffolds and exhibit a full spectrum of biological activities. This review throws light on the detailed synthetic approaches which have been applied for the synthesis of pyrazole. This has been followed by an in depth analysis of the pyrazole with respect to their medical significance. This follow-up may help the medicinal chemists to generate new leads possessing pyrazole nucleus with high efficacy. PMID:26957862

  13. Oxyresveratrol: Structural Modification and Evaluation of Biological Activities.

    PubMed

    Chatsumpun, Nutputsorn; Chuanasa, Taksina; Sritularak, Boonchoo; Lipipun, Vimolmas; Jongbunprasert, Vichien; Ruchirawat, Somsak; Ploypradith, Poonsakdi; Likhitwitayawuid, Kittisak

    2016-01-01

    Oxyresveratrol (2,4,3',5'-tetrahydroxystilbene, 1), a phytoalexin present in large amounts in the heartwood of Artocarpus lacucha Buch.-Ham., has been reported to possess a wide variety of biological activities. As part of our continuing studies on the structural modification of oxyresveratrol, a library of twenty-six compounds was prepared via O-alkylation, aromatic halogenation, and electrophilic aromatic substitution. The two aromatic rings of the stilbene system of 1 can be chemically modulated by exploiting different protecting groups. Such a strategy allows for selective and exclusive modifications on either ring A or ring B. All compounds were evaluated in vitro for a panel of biological activities, including free radical scavenging activity, DNA protective properties, antiherpetic activity, inhibition of α-glucosidase and neuraminidase, and cytotoxicity against some cancer cell lines. Several derivatives were comparably active or even more potent than the parent oxyresveratrol and/or the appropriate positive controls. The partially etherified analogs 5'-hydroxy-2,3',4-trimethoxystilbene and 3',5'-dihydroxy-2,4-dimethoxystilbene demonstrated promising anti-herpetic and DNA protective activities, offering new leads for neuropreventive agent research, whereas 5'-hydroxy-2,3',4,-triisopropoxystilbene displayed anti-α-glucosidase effects, providing a new lead molecule for anti-diabetic drug development. 3',5'-Diacetoxy-2,4-diisopropoxystilbene showed potent and selective cytotoxicity against HeLa cancer cells, but the compound still needs further in vivo investigation to verify its anticancer potential. PMID:27104505

  14. Myricetin: A Dietary Molecule with Diverse Biological Activities.

    PubMed

    Semwal, Deepak Kumar; Semwal, Ruchi Badoni; Combrinck, Sandra; Viljoen, Alvaro

    2016-02-01

    Myricetin is a common plant-derived flavonoid and is well recognised for its nutraceuticals value. It is one of the key ingredients of various foods and beverages. The compound exhibits a wide range of activities that include strong anti-oxidant, anticancer, antidiabetic and anti-inflammatory activities. It displays several activities that are related to the central nervous system and numerous studies have suggested that the compound may be beneficial to protect against diseases such as Parkinson's and Alzheimer's. The use of myricetin as a preserving agent to extend the shelf life of foods containing oils and fats is attributed to the compound's ability to protect lipids against oxidation. A detailed search of existing literature revealed that there is currently no comprehensive review available on this important molecule. Hence, the present work includes the history, synthesis, pharmaceutical applications and toxicity studies of myricetin. This report also highlights structure-activity relationships and mechanisms of action for various biological activities. PMID:26891321

  15. Biological activities and phytochemicals of Swietenia macrophylla King.

    PubMed

    Moghadamtousi, Soheil Zorofchian; Goh, Bey Hing; Chan, Chim Kei; Shabab, Tara; Kadir, Habsah Abdul

    2013-01-01

    Swietenia macrophylla King (Meliaceae) is an endangered and medicinally important plant indigenous to tropical and subtropical regions of the World. S. macrophylla has been widely used in folk medicine to treat various diseases. The review reveals that limonoids and its derivatives are the major constituents of S. macrophylla. There are several data in the literature indicating a great variety of pharmacological activities of S. macrophylla, which exhibits antimicrobial, anti-inflammatory, antioxidant effects, antimutagenic, anticancer, antitumor and antidiabetic activities. Various other activities like anti-nociceptive, hypolipidemic, antidiarrhoeal, anti-infective, antiviral, antimalarial, acaricidal, antifeedant and heavy metal phytoremediation activity have also been reported. In view of the immense medicinal importance of S. macrophylla, this review aimed at compiling all currently available information on its ethnomedicinal uses, phytochemistry and biological activities of S. macrophylla, showing its importance. PMID:23999722

  16. Integrity and Biological Activity of DNA after UV Exposure

    NASA Astrophysics Data System (ADS)

    Lyon, Delina Y.; Monier, Jean-Michel; Dupraz, Sébastien; Freissinet, Caroline; Simonet, Pascal; Vogel, Timothy M.

    2010-04-01

    The field of astrobiology lacks a universal marker with which to indicate the presence of life. This study supports the proposal to use nucleic acids, specifically DNA, as a signature of life (biosignature). In addition to its specificity to living organisms, DNA is a functional molecule that can confer new activities and characteristics to other organisms, following the molecular biology dogma, that is, DNA is transcribed to RNA, which is translated into proteins. Previous criticisms of the use of DNA as a biosignature have asserted that DNA molecules would be destroyed by UV radiation in space. To address this concern, DNA in plasmid form was deposited onto different surfaces and exposed to UVC radiation. The surviving DNA was quantified via the quantitative polymerase chain reaction (qPCR). Results demonstrate increased survivability of DNA attached to surfaces versus non-adsorbed DNA. The DNA was also tested for biological activity via transformation into the bacterium Acinetobacter sp. and assaying for antibiotic resistance conferred by genes encoded by the plasmid. The success of these methods to detect DNA and its gene products after UV exposure (254 nm, 3.5 J/m2s) not only supports the use of the DNA molecule as a biosignature on mineral surfaces but also demonstrates that the DNA retained biological activity.

  17. Integrity and biological activity of DNA after UV exposure.

    PubMed

    Lyon, Delina Y; Monier, Jean-Michel; Dupraz, Sébastien; Freissinet, Caroline; Simonet, Pascal; Vogel, Timothy M

    2010-04-01

    The field of astrobiology lacks a universal marker with which to indicate the presence of life. This study supports the proposal to use nucleic acids, specifically DNA, as a signature of life (biosignature). In addition to its specificity to living organisms, DNA is a functional molecule that can confer new activities and characteristics to other organisms, following the molecular biology dogma, that is, DNA is transcribed to RNA, which is translated into proteins. Previous criticisms of the use of DNA as a biosignature have asserted that DNA molecules would be destroyed by UV radiation in space. To address this concern, DNA in plasmid form was deposited onto different surfaces and exposed to UVC radiation. The surviving DNA was quantified via the quantitative polymerase chain reaction (qPCR). Results demonstrate increased survivability of DNA attached to surfaces versus non-adsorbed DNA. The DNA was also tested for biological activity via transformation into the bacterium Acinetobacter sp. and assaying for antibiotic resistance conferred by genes encoded by the plasmid. The success of these methods to detect DNA and its gene products after UV exposure (254 nm, 3.5 J/m(2)s) not only supports the use of the DNA molecule as a biosignature on mineral surfaces but also demonstrates that the DNA retained biological activity. PMID:20446869

  18. Crystal Structure of Human Arginase l Complexed with Thiosemicarbazide Reveals an Unusual Thiocarbonly u-Sulfide Ligand in the Binuclear Manganese Cluster

    SciTech Connect

    Di Costanzo,L.; Pique, M.; Christianson, D.

    2007-01-01

    The crystal structure of the human arginase I-thiosemicarbazide complex reveals an unusual thiocarbonyl {mu}-sulfide ligand in the binuclear manganese cluster. The CS moiety of thiosemicarbazide bridges Mn2+A and Mn2+B with coordination distances of 2.6 and 2.4 Angstroms, respectively. Otherwise, the binding of thiosemicarbazide to human arginase I does not cause any significant structural changes in the active site. The crystal structure of the unliganded enzyme reveals a hydrogen-bonded water molecule that could support proton transfer between a {mu}-water molecule and H141 to regenerate the nucleophilic {mu}-hydroxide ion in the final step of catalysis.

  19. Isolation of biologically active nanomaterial (inclusion bodies) from bacterial cells

    PubMed Central

    2010-01-01

    Background In recent years bacterial inclusion bodies (IBs) were recognised as highly pure deposits of active proteins inside bacterial cells. Such active nanoparticles are very interesting for further downstream protein isolation, as well as for many other applications in nanomedicine, cosmetic, chemical and pharmaceutical industry. To prepare large quantities of a high quality product, the whole bioprocess has to be optimised. This includes not only the cultivation of the bacterial culture, but also the isolation step itself, which can be of critical importance for the production process. To determine the most appropriate method for the isolation of biologically active nanoparticles, three methods for bacterial cell disruption were analyzed. Results In this study, enzymatic lysis and two mechanical methods, high-pressure homogenization and sonication, were compared. During enzymatic lysis the enzyme lysozyme was found to attach to the surface of IBs, and it could not be removed by simple washing. As this represents an additional impurity in the engineered nanoparticles, we concluded that enzymatic lysis is not the most suitable method for IBs isolation. During sonication proteins are released (lost) from the surface of IBs and thus the surface of IBs appears more porous when compared to the other two methods. We also found that the acoustic output power needed to isolate the IBs from bacterial cells actually damages proteins structures, thereby causing a reduction in biological activity. High-pressure homogenization also caused some damage to IBs, however the protein loss from the IBs was negligible. Furthermore, homogenization had no side-effects on protein biological activity. Conclusions The study shows that among the three methods tested, homogenization is the most appropriate method for the isolation of active nanoparticles from bacterial cells. PMID:20831775

  20. Isothiocyanate synthetic analogs: biological activities, structure-activity relationships and synthetic strategies.

    PubMed

    Milelli, Andrea; Fimognari, Carmela; Ticchi, Nicole; Neviani, Paolo; Minarini, Anna; Tumiatti, Vincenzo

    2014-01-01

    Sulforaphane is a natural product that is constantly under biological investigation for its unique biological properties. This naturally occurring isothiocyanate (ITC) and its analogs are the main components of cruciferous vegetables, such as cauliflower, watercress, broccoli, cabbage, Brussels sprouts, widely used as chemopreventive agents. Due to their interesting biological profiles, natural ITCs have been exploited as starting point to develop new synthetic analogs. The present mini-review briefly highlights the most important biological actions of selected new synthetic ITCs focusing on their structure-activity relationships and related synthetic strategies. PMID:25373847

  1. Binuclear bromide complex of Bi(III): Thermally induced changes in optical properties

    NASA Astrophysics Data System (ADS)

    Adonin, Sergey A.; Sokolov, Maxim N.; Rakhmanova, Marianna E.; Smolentsev, Anton I.; Pishchur, Denis P.; Korolkov, Ilya V.; Kozlova, Svetlana G.; Fedin, Vladimir P.

    2016-05-01

    Binuclear bromobismuthate complex (H2bipy)2[Bi2Br10] (1) displays the optical properties: 1) thermochromism, 2) disappearance/appearance of luminescence at 298/77 K. To investigate this feature, a combination of X-ray diffractometry, differential scanning calorimetry (DSC) and quantum chemical calculations has been used.

  2. Chemistry, biological activity, and uses of formamidine pesticides.

    PubMed Central

    Hollingworth, R M

    1976-01-01

    The formamidines, a relatively new group of acaricide-insecticides, are novel both in their range of biological activities and in their mode of action, which is presently unknown. This paper is a review of the historical development, properties, structures, uses, and chemistry of this group of pesticides, with particular emphasis on chlordimeform (Galecron or Fundal), N'-4-chloro-o-tolyl-N,N-dimethylformamidine, and amitraz, 1,3=di-(2,4-dimethylphenylimino)-2-methyl-2-azapropane. Their biological activity and uses are defined by their toxicity to spider mites, ticks, and certain insects, and they are particularly effective against juvenile and resistant forms of these organisms. A significant, but poorly understood feature of their field effectiveness is their breadth of toxic action which includes direct lethality, excitant-repellant behavioral effects, and chemosterilization. They are generally of low hazard for nontarget species with the significant exception of predaceous mites. Several aspects of the chemistry of these compounds are considered, including structure--activity relations, synthetic pathways, isomerism and configuration, and their chemical and environmental stability. A significant feature of the metabolism and toxicity of these agents is the possible activation of chlordimeform by N-demethylation in vivo. Strong evidence for this has been presented with the cattle tick, but recent results discussed here suggest that in other species, i.e., mice, German cockroaches or black cutworm eggs, N-demethylation is neither a strong activation nor a detoxication reaction. PMID:789070

  3. On the mechanism of biological activation by tritium.

    PubMed

    Rozhko, T V; Badun, G A; Razzhivina, I A; Guseynov, O A; Guseynova, V E; Kudryasheva, N S

    2016-06-01

    The mechanism of biological activation by beta-emitting radionuclide tritium was studied. Luminous marine bacteria were used as a bioassay to monitor the biological effect of tritium with luminescence intensity as the physiological parameter tested. Two different types of tritium sources were used: HTO molecules distributed regularly in the surrounding aqueous medium, and a solid source with tritium atoms fixed on its surface (tritium-labeled films, 0.11, 0.28, 0.91, and 2.36 MBq/cm(2)). When using the tritium-labeled films, tritium penetration into the cells was prevented. The both types of tritium sources revealed similar changes in the bacterial luminescence kinetics: a delay period followed by bioluminescence activation. No monotonic dependences of bioluminescence activation efficiency on specific radioactivities of the films were found. A 15-day exposure to tritiated water (100 MBq/L) did not reveal mutations in bacterial DNA. The results obtained give preference to a "non-genomic" mechanism of bioluminescence activation by tritium. An activation of the intracellular bioluminescence process develops without penetration of tritium atoms into the cells and can be caused by intensification of trans-membrane cellular processes stimulated by ionization and radiolysis of aqueous media. PMID:27035890

  4. Distribution and biological activities of the flavonoid luteolin.

    PubMed

    López-Lázaro, Miguel

    2009-01-01

    Epidemiological evidence suggests that flavonoids may play an important role in the decreased risk of chronic diseases associated with a diet rich in plant-derived foods. Flavonoids are also common constituents of plants used in traditional medicine to treat a wide range of diseases. The purpose of this article is to summarize the distribution and biological activities of one of the most common flavonoids: luteolin. This flavonoid and its glycosides are widely distributed in the plant kingdom; they are present in many plant families and have been identified in Bryophyta, Pteridophyta, Pinophyta and Magnoliophyta. Dietary sources of luteolin include, for instance, carrots, peppers, celery, olive oil, peppermint, thyme, rosemary and oregano. Preclinical studies have shown that this flavone possesses a variety of pharmacological activities, including antioxidant, anti-inflammatory, antimicrobial and anticancer activities. The ability of luteolin to inhibit angiogenesis, to induce apoptosis, to prevent carcinogenesis in animal models, to reduce tumor growth in vivo and to sensitize tumor cells to the cytotoxic effects of some anticancer drugs suggests that this flavonoid has cancer chemopreventive and chemotherapeutic potential. Modulation of ROS levels, inhibition of topoisomerases I and II, reduction of NF-kappaB and AP-1 activity, stabilization of p53, and inhibition of PI3K, STAT3, IGF1R and HER2 are possible mechanisms involved in the biological activities of luteolin. PMID:19149659

  5. Biological Activities of Phenolic Compounds of Extra Virgin Olive Oil.

    PubMed

    Servili, Maurizio; Sordini, Beatrice; Esposto, Sonia; Urbani, Stefania; Veneziani, Gianluca; Di Maio, Ilona; Selvaggini, Roberto; Taticchi, Agnese

    2013-01-01

    Over the last few decades, multiple biological properties, providing antioxidant, anti-inflammatory, chemopreventive and anti-cancer benefits, as well as the characteristic pungent and bitter taste, have been attributed to Extra Virgin Olive Oil (EVOO) phenols. In particular, growing efforts have been devoted to the study of the antioxidants of EVOO, due to their importance from health, biological and sensory points of view. Hydrophilic and lipophilic phenols represent the main antioxidants of EVOO, and they include a large variety of compounds. Among them, the most concentrated phenols are lignans and secoiridoids, with the latter found exclusively in the Oleaceae family, of which the drupe is the only edible fruit. In recent years, therefore, we have tackled the study of the main properties of phenols, including the relationships between their biological activity and the related chemical structure. This review, in fact, focuses on the phenolic compounds of EVOO, and, in particular, on their biological properties, sensory aspects and antioxidant capacity, with a particular emphasis on the extension of the product shelf-life. PMID:26784660

  6. Biological Activities of Phenolic Compounds of Extra Virgin Olive Oil

    PubMed Central

    Servili, Maurizio; Sordini, Beatrice; Esposto, Sonia; Urbani, Stefania; Veneziani, Gianluca; Maio, Ilona Di; Selvaggini, Roberto; Taticchi, Agnese

    2013-01-01

    Over the last few decades, multiple biological properties, providing antioxidant, anti-inflammatory, chemopreventive and anti-cancer benefits, as well as the characteristic pungent and bitter taste, have been attributed to Extra Virgin Olive Oil (EVOO) phenols. In particular, growing efforts have been devoted to the study of the antioxidants of EVOO, due to their importance from health, biological and sensory points of view. Hydrophilic and lipophilic phenols represent the main antioxidants of EVOO, and they include a large variety of compounds. Among them, the most concentrated phenols are lignans and secoiridoids, with the latter found exclusively in the Oleaceae family, of which the drupe is the only edible fruit. In recent years, therefore, we have tackled the study of the main properties of phenols, including the relationships between their biological activity and the related chemical structure. This review, in fact, focuses on the phenolic compounds of EVOO, and, in particular, on their biological properties, sensory aspects and antioxidant capacity, with a particular emphasis on the extension of the product shelf-life. PMID:26784660

  7. Controlled Release of Biologically Active Silver from Nanosilver Surfaces

    PubMed Central

    Liu, Jingyu; Sonshine, David A.; Shervani, Saira; Hurt, Robert H.

    2010-01-01

    Major pathways in the antibacterial activity and eukaryotic toxicity of nano-silver involve the silver cation and its soluble complexes, which are well established thiol toxicants. Through these pathways, nano-silver behaves in analogy to a drug delivery system, in which the particle contains a concentrated inventory of an active species, the ion, which is transported to and released near biological target sites. Although the importance of silver ion in the biological response to nano-silver is widely recognized, the drug delivery paradigm has not been well developed for this system, and there is significant potential to improve nano-silver technologies through controlled release formulations. This article applies elements of the drug delivery paradigm to nano-silver dissolution and presents a systematic study of chemical concepts for controlled release. After presenting thermodynamic calculations of silver species partitioning in biological media, the rates of oxidative silver dissolution are measured for nanoparticles and macroscopic foils and used to derive unified area-based release kinetics. A variety of competing chemical approaches are demonstrated for controlling the ion release rate over four orders of magnitude. Release can be systematically slowed by thiol and citrate ligand binding, formation of sulfidic coatings, or the scavenging of peroxy-intermediates. Release can be accelerated by pre-oxidation or particle size reduction, while polymer coatings with complexation sites alter the release profile by storing and release inventories of surface-bound silver. Finally, the ability to tune biological activity is demonstrated through bacterial inhibition zone assay carried out on selected formulations of controlled release nano-silver. PMID:20968290

  8. Biological activities of water-soluble fullerene derivatives

    NASA Astrophysics Data System (ADS)

    Nakamura, S.; Mashino, T.

    2009-04-01

    Three types of water-soluble fullerene derivatives were synthesized and their biological activities were investigated. C60-dimalonic acid, an anionic fullerene derivative, showed antioxidant activity such as quenching of superoxide and relief from growth inhibition of E. coli by paraquat. C60-bis(7V,7V-dimethylpyrrolidinium iodide), a cationic fullerene derivative, has antibacterial activity and antiproliferative effect on cancer cell lines. The mechanism is suggested to be respiratory chain inhibition by reactive oxygen species produced by the cationic fullerene derivative. Proline-type fullerene derivatives showed strong inhibition activities on HIV-reverse transcriptase. The IC50 values were remarkably lower than nevirapine, a clinically used anti-HIV drug. Fullerene derivatives have a big potential for a new type of lead compound to be used as medicine.

  9. Synthesis, properties and thermal studies of oxorhenium(V) complexes with 3-hydrazino-5,6-diphenyl-1,2,4-triazine, benzimidazolethione and 2-hydrazinobenzimidazole. Mixed ligand complexes, pyrolytical products and biological activity

    NASA Astrophysics Data System (ADS)

    Mashaly, M. M.; El-Shafiy, H. F.; El-Maraghy, S. B.; Habib, H. A.

    2005-06-01

    A series of biologically active complexes of oxorhenium(V), were prepared by using the organic ligands 3-hydrazino-5,6-diphenyl-1,2,4-triazine (HL 1), benzimidazolethione (H 2L 2) and 2-hydrazinobenzimidazole (H 2L 3). The mixed ligand complexes of oxorhenium(V) with the previous ligands and one of the following ligands: NH 4SCN, 1,10-phenanthroline (1,10-phen), 8-hydroxyquinoline (8-OHquin) or glycine (Gly), were isolated. All the binary and mixed ligand complexes have monomeric structures and exist in the octahedral configuration. Thermal studies on these complexes showed the possibility of structural transformation from mononuclear into binuclear ones. The structures of all complexes and the corresponding thermal products were elucidated by elemental analyses, IR, electronic absorption and 1H NMR spectra, magnetic moments, conductance and TG-DSC measurements. The antifungal activities of the metal complexes towards Alternaria alternata and Aspergilus niger were tested and showed comparable behaviour with some well known antibiotics.

  10. Natural products as a resource for biologically active compounds

    SciTech Connect

    Hanke, F.J.

    1986-01-01

    The goal of this study was to investigate various sources of biologically active natural products in an effort to identify the active pesticidal compounds involved. The study is divided into several parts. Chapter 1 contains a discussion of several new compounds from plant and animal sources. Chapter 2 introduces a new NMR technique. In section 2.1 a new technique for better utilizing the lanthanide relaxation agent Gd(fod)/sub 3/ is presented which allows the predictable removal of resonances without line broadening. Section 2.2 discusses a variation of this technique for use in an aqueous solvent by applying this technique towards identifying the binding sites of metals of biological interest. Section 2.3 presents an unambiguous /sup 13/C NMR assignment of melibiose. Chapter 3 deals with work relating to the molting hormone of most arthropods, 20-hydroxyecdysone. Section 3.1 discusses the use of two-dimensional NMR (2D NMR) to assign the /sup 1/H NMR spectrum of this biologically important compound. Section 3.2 presents a new application for Droplet countercurrent chromatography (DCCC). Chapter 4 presents a basic improvement to the commercial DCCC instrument that is currently being applied to future commercial instruments. Chapter 5 discusses a curious observation of the effects that two previously known compounds, nagilactone C and (-)-epicatechin, have on lettuce and rice and suggest a possible new role for the ubiquitous flavanol (-)-epicatechin in plants.

  11. Structure dependence of biological activities for primate cathelicidins.

    PubMed

    Tomasinsig, Linda; Morgera, Francesca; Antcheva, Nikolinka; Pacor, Sabrina; Skerlavaj, Barbara; Zanetti, Margherita; Tossi, Alessandro

    2009-09-01

    We have analysed the effects of variations in orang-utan (ppy), rhesus macaque (mmu) and leaf eater (pob) monkey orthologues of the human cathelicidin LL-37, on a range of relevant biological activities. These host defence peptides range in cationicity from +4 to +10, and while the more cationic pob and mmuRL-37 are in a monomeric and unstructured form in bulk solution (F-form), the human and ppyLL-37 are in an aggregated/helical form (A-form). The in vitro antibacterial activity depended strongly on both the structural form and the charge. F-form peptides were more potent against Gram-positive and -negative bacteria and less salt, medium or serum sensitive than A-form ones. CD studies suggested that A- and F-form peptides interact with LPS in different manners, but the ability to detoxify it did not correlate directly with either the charge or structure. Toxicity towards eukaryotic cells also showed a varied dependence on the peptides' physical characteristics. Haemolytic activity was similar for all the tested peptides while other cytotoxicity assays revealed the highly cationic, F-form pobRL-37 as the most toxic, followed by the A-form human LL-37. As shown with the human peptide, toxicity depended markedly on the nature and metabolic state of the target cell. Our results suggest that different evolutionary trajectories for each orthologue lead to distinct sets of physical characteristics, which significantly differentiates their biological activities. PMID:19472166

  12. Biologically Active Metabolites Produced by the Basidiomycete Quambalaria cyanescens

    PubMed Central

    Stodůlková, Eva; Císařová, Ivana; Kolařík, Miroslav; Chudíčková, Milada; Novák, Petr; Man, Petr; Kuzma, Marek; Pavlů, Barbora; Černý, Jan; Flieger, Miroslav

    2015-01-01

    Four strains of the fungus Quambalaria cyanescens (Basidiomycota: Microstromatales), were used for the determination of secondary metabolites production and their antimicrobial and biological activities. A new naphthoquinone named quambalarine A, (S)-(+)-3-(5-ethyl-tetrahydrofuran-2-yliden)-5,7,8-trihydroxy-2-oxo-1,4-naphthoquinone (1), together with two known naphthoquinones, 3-hexanoyl-2,5,7,8-tetrahydroxy-1,4-naphthoquinone (named here as quambalarine B, 2) and mompain, 2,5,7,8-tetrahydroxy-1,4-naphthoquinone (3) were isolated. Their structures were determined by single-crystal X-ray diffraction crystallography, NMR and MS spectrometry. Quambalarine A (1) had a broad antifungal and antibacterial activity and is able inhibit growth of human pathogenic fungus Aspergillus fumigatus and fungi co-occurring with Q. cyanescens in bark beetle galleries including insect pathogenic species Beauveria bassiana. Quambalarine B (2) was active against several fungi and mompain mainly against bacteria. The biological activity against human-derived cell lines was selective towards mitochondria (2 and 3); after long-term incubation with 2, mitochondria were undetectable using a mitochondrial probe. A similar effect on mitochondria was observed also for environmental competitors of Q. cyanescens from the genus Geosmithia. PMID:25723150

  13. Application of activation techniques to biological analysis. [813 references

    SciTech Connect

    Bowen, H.J.M.

    1981-12-01

    Applications of activation analysis in the biological sciences are reviewed for the period of 1970 to 1979. The stages and characteristics of activation analysis are described, and its advantages and disadvantages enumerated. Most applications involve activation by thermal neutrons followed by either radiochemical or instrumental determination. Relatively little use has been made of activation by fast neutrons, photons, or charged particles. In vivo analyses are included, but those based on prompt gamma or x-ray emission are not. Major applications include studies of reference materials, and the elemental analysis of plants, marine biota, animal and human tissues, diets, and excreta. Relatively little use of it has been made in biochemistry, microbiology, and entomology, but it has become important in toxicology and environmental science. The elements most often determined are Ag, As, Au, Br, Ca, Cd, Cl, Co, Cr, Cs, Cu, Fe, Hg, I, K, Mn, Mo, Na, Rb, Sb, Sc, Se, and Zn, while few or no determinations of B, Be, Bi, Ga, Gd, Ge, H, In, Ir, Li, Nd, Os, Pd, Pr, Pt, Re, Rh, Ru, Te, Tl, or Y have been made in biological materials.

  14. Perceived causality influences brain activity evoked by biological motion.

    PubMed

    Morris, James P; Pelphrey, Kevin A; McCarthy, Gregory

    2008-01-01

    Using functional magnetic resonance imaging (fMRI), we investigated brain activity in an observer who watched the hand and arm motions of an individual when that individual was, or was not, the cause of the motion. Subjects viewed a realistic animated 3D character who sat at a table containing four pistons. On Intended Motion trials, the character raised his hand and arm upwards. On Unintended Motion trials, the piston under one of the character's hands pushed the hand and arm upward with the same motion. Finally, during Non-Biological Motion control trials, a piston pushed a coffee mug upward in the same smooth motion. Hand and arm motions, regardless of intention, evoked significantly more activity than control trials in a bilateral region that extended ventrally from the posterior superior temporal sulcus (pSTS) region and which was more spatially extensive in the right hemisphere. The left pSTS near the temporal-parietal junction, robustly differentiated between the Intended Motion and Unintended Motion conditions. Here, strong activity was observed for Intended Motion trials, while Unintended Motion trials evoked similar activity as the coffee mug trials. Our results demonstrate a strong hemispheric bias in the role of the pSTS in the perception of causality of biological motion. PMID:18633843

  15. Ion exchange defines the biological activity of titanate nanotubes.

    PubMed

    Rónavári, Andrea; Kovács, Dávid; Vágvölgyi, Csaba; Kónya, Zoltán; Kiricsi, Mónika; Pfeiffer, Ilona

    2016-05-01

    One-dimensional titanate nanotubes (TiONTs) were subjected to systematic ion exchange to determine the impact of these modifications on biological activities. Ion exchanged TiONTs (with Ag, Mg, Bi, Sb, Ca, K, Sr, Fe, and Cu ions) were successfully synthesized and the presence of the substituted ions was verified by energy dispersive X-ray spectroscopy (EDS). A complex screening was carried out to reveal differences in toxicity to human cells, as well as in antibacterial, antifungal, and antiviral activities between the various modified nanotubes. Our results demonstrated that Ag ion exchanged TiONTs exerted potent antibacterial and antifungal effects against all examined microbial species but were ineffective on viruses. Surprisingly, the antibacterial activity of Cu/TiONTs was restricted to Micrococcus luteus. Most ion exchanged TiONTs did not show antimicrobial activity against the tested bacterial and fungal species. Incorporation of various ions into nanotube architectures lead to mild, moderate, or even to a massive loss of human cell viability; therefore, this type of biological effect exerted by TiONTs can be greatly modulated by ion exchange. These findings further emphasize the contribution of ion exchange in determining not only the physical and chemical characteristics but also the bioactivity of TiONT against different types of living cells. PMID:26972521

  16. Mutant p53: Multiple Mechanisms Define Biologic Activity in Cancer

    PubMed Central

    Kim, Michael Paul; Zhang, Yun; Lozano, Guillermina

    2015-01-01

    The functional importance of p53 as a tumor suppressor gene is evident through its pervasiveness in cancer biology. The p53 gene is the most commonly altered gene in human cancer; however, not all genetic alterations are biologically equivalent. The majority of alterations involve p53 missense mutations that result in the production of mutant p53 proteins. Such mutant p53 proteins lack normal p53 function and may concomitantly gain novel functions, often with deleterious effects. Here, we review characterized mechanisms of mutant p53 gain of function in various model systems. In addition, we review mutant p53 addiction as emerging evidence suggests that tumors may depend on sustained mutant p53 activity for continued growth. We also discuss the role of p53 in stromal elements and their contribution to tumor initiation and progression. Lastly, current genetic mouse models of mutant p53 in various organ systems are reviewed and their limitations discussed. PMID:26618142

  17. Preparation and characterization of new biologically active polyurethane foams.

    PubMed

    Savelyev, Yuri; Veselov, Vitali; Markovskaya, Ludmila; Savelyeva, Olga; Akhranovich, Elena; Galatenko, Natalya; Robota, Ludmila; Travinskaya, Tamara

    2014-12-01

    Biologically active polyurethane foams are the fast-developed alternative to many applications of biomedical materials. Due to the polyurethane structure features and foam technology it is possible to incorporate into their structure the biologically active compounds of target purpose via structural-chemical modification of macromolecule. A series of new biologically active polyurethane foams (PUFs) was synthesized with polyethers (MM 2500-5000), polyesters MM (500-2200), 2,4(2,6) toluene diisocyanate, water as a foaming agent, catalysts, foam stabilizers and functional compounds. Different functional compounds: 1,4-di-N-oxy-2,3-bis-(oxymethyl)-quinoxaline (DOMQ), partial sodium salt of poly(acrylic acid) and 2,6-dimethyl-N,N-diethyl aminoacetatanilide hydrochloride were incorporated into the polymer structure/composition due to the chemical and/or physical bonding. Structural peculiarities of PUFs were studied by FTIR spectroscopy and X-ray scattering. Self-adhesion properties of PUFs were estimated by measuring of tensile strength at break of adhesive junction. The optical microscopy method was performed for the PUF morphology studies. Toxicological estimation of the PUFs was carried out in vitro and in vivo. The antibacterial action towards the Gram-positive and Gram-negative bacteria (Escherichia coli ATC 25922, E. coli ATC 2150, Klebsiella pneumoniae 6447, Staphylococcus aureus 180, Pseudomonas aeruginosa 8180, Proteus mirabilis F 403, P. mirabilis 6054, and Proteus vulgaris 8718) was studied by the disc method on the solid nutrient. Physic-chemical properties of the PUFs (density, tensile strength and elongation at break, water absorption and vapor permeability) showed that all studied PUFs are within the operational requirements for such materials and represent fine-cellular foams. Spectral studies confirmed the incorporation of DOMQ into the PUF's macrochain. PUFs are characterized by microheterogeneous structure. They are antibacterially active, non

  18. Soil biological activity at European scale - two calculation concepts

    NASA Astrophysics Data System (ADS)

    Krüger, Janine; Rühlmann, Jörg

    2014-05-01

    The CATCH-C project aims to identify and improve the farm-compatibility of Soil Management Practices including to promote productivity, climate change mitigation and soil quality. The focus of this work concentrates on turnover conditions for soil organic matter (SOM). SOM is fundamental for the maintenance of quality and functions of soils while SOM storage is attributed a great importance in terms of climate change mitigation. The turnover conditions depend on soil biological activity characterized by climate and soil properties. To assess the turnover conditions two model concepts are applied: (I) Biological active time (BAT) regression approach derived from CANDY model (Franko & Oelschlägel 1995) expresses the variation of air temperature, precipitation and soil texture as a timescale and an indicator of biological activity for soil organic matter (SOM) turnover. (II) Re_clim parameter within the Introductory Carbon Balance Model (Andrén & Kätterer 1997) states the soil temperature and soil water to estimate soil biological activity. The modelling includes two strategies to cover the European scale and conditions. BAT was calculated on a 20x20 km grid basis. The European data sets of precipitation and air temperature (time period 1901-2000, monthly resolution), (Mitchell et al. 2004) were used to derive long-term averages. As we focus on agricultural areas we included CORINE data (2006) to extract arable land. The resulting BATs under co-consideration of the main soil textures (clay, silt, sand and loam) were investigated per environmental zone (ENZs, Metzger et al. 2005) that represents similar conditions for precipitation, temperature and relief to identify BAT ranges and hence turnover conditions for each ENZ. Re_clim was quantified by climatic time series of more than 250 weather stations across Europe presented by Klein Tank et al. (2002). Daily temperature, precipitation and potential evapotranspiration (maximal thermal extent) were used to calculate

  19. CANTHARELLUS CIBARIUS - CULINARY-MEDICINAL MUSHROOM CONTENT AND BIOLOGICAL ACTIVITY.

    PubMed

    Muszyńska, Bozena; Kała, Katarzyna; Firlej, Anna; Sułkowska-Ziaja, Katarzyna

    2016-01-01

    One of the most frequently harvested mushrooms in Polish forests is Yellow chanterelle (chanterelle) - Cantharellus cibarius Fr. from the Cantharellaceae family. Chanterelle is an ectomycorrhizal mushroom occurring in Poland. Chanterelle lives in symbiosis with pine, spruce, oak and hombeam. In cookery, chanterelle is appreciated because of the aroma, taste, firmness and crunchiness of its fruiting bodies. Wild edible mushrooms are widely consumed in Asia, Western Europe and Central America. Chanterelle contains a great number of carbohydrates and proteins and a low amount of fat. Actual review presents the main groups of physiologically active primary and secondary metabolites in the fruiting bodies of chanterelle such as indole and phenolic compounds, carbohydrates, fatty acids, proteins, free amino acids, sterols, carotenoids, enzymes, vitamins and elements with biological activity. The presence of these compounds and elements conditions the nutrient and therapeutic activity of chanterelle, e.g., immunomodulatory, anti-inflammatory, antioxidant, antiviral, antimicrobial and antigenotoxic properties. PMID:27476275

  20. Biological and therapeutic activities, and anticancer properties of curcumin

    PubMed Central

    PERRONE, DONATELLA; ARDITO, FATIMA; GIANNATEMPO, GIOVANNI; DIOGUARDI, MARIO; TROIANO, GIUSEPPE; LO RUSSO, LUCIO; DE LILLO, ALFREDO; LAINO, LUIGI; LO MUZIO, LORENZO

    2015-01-01

    Curcumin (diferuloylmethane) is a polyphenol derived from the Curcuma longa plant. Curcumin has been used extensively in Ayurvedic medicine, as it is nontoxic and exhibits a variety of therapeutic properties, including antioxidant, analgesic, anti-inflammatory and antiseptic activities. Recently, certain studies have indicated that curcumin may exert anticancer effects in a variety of biological pathways involved in mutagenesis, apoptosis, tumorigenesis, cell cycle regulation and metastasis. The present study reviewed previous studies in the literature, which support the therapeutic activity of curcumin in cancer. In addition, the present study elucidated a number of the challenges concerning the use of curcumin as an adjuvant chemotherapeutic agent. All the studies reviewed herein suggest that curcumin is able to exert anti-inflammatory, antiplatelet, antioxidative, hepatoprotective and antitumor activities, particularly against cancers of the liver, skin, pancreas, prostate, ovary, lung and head neck, as well as having a positive effect in the treatment of arthritis. PMID:26640527

  1. Hydrodynamic collective effects of active proteins in biological membranes.

    PubMed

    Koyano, Yuki; Kitahata, Hiroyuki; Mikhailov, Alexander S

    2016-08-01

    Lipid bilayers forming biological membranes are known to behave as viscous two-dimensional fluids on submicrometer scales; usually they contain a large number of active protein inclusions. Recently, it was shown [A. S. Mikhailov and R. Kapral, Proc. Natl. Acad. Sci. USA 112, E3639 (2015)PNASA60027-842410.1073/pnas.1506825112] that such active proteins should induce nonthermal fluctuating lipid flows leading to diffusion enhancement and chemotaxislike drift for passive inclusions in biomembranes. Here, a detailed analytical and numerical investigation of such effects is performed. The attention is focused on the situations when proteins are concentrated within lipid rafts. We demonstrate that passive particles tend to become attracted by active rafts and are accumulated inside them. PMID:27627343

  2. Biological activities of aqueous extract from Cinnamomum porrectum

    NASA Astrophysics Data System (ADS)

    Farah, H. Siti; Nazlina, I.; Yaacob, W. A.

    2013-11-01

    A study was carried out to evaluate biological activities of an extract obtained from Cinnamomum porrectum under reflux using water. Aqueous extract of Cinnamomum porrectum was tested for antibacterial activity against six Gram-positive and eight Gram-negative bacteria as well as MRSA. The results confirmed that the aqueous extract of Cinnamomum porrectum was bactericidal. Cytotoxic tests on Vero cell culture revealed that Cinnamomum porrectum was non-toxic which IC50 value higher than 0.02 mg/mL. Antiviral activity was tested based on the above IC50 values together with the measured EC50 values to obtain Therapeutic Index. The result showed that Cinnamomum porrectum has the ability to inhibit viral replication of HSV-1 in Vero cells.

  3. Students' Learning Activities While Studying Biological Process Diagrams

    NASA Astrophysics Data System (ADS)

    Kragten, Marco; Admiraal, Wilfried; Rijlaarsdam, Gert

    2015-08-01

    Process diagrams describe how a system functions (e.g. photosynthesis) and are an important type of representation in Biology education. In the present study, we examined students' learning activities while studying process diagrams, related to their resulting comprehension of these diagrams. Each student completed three learning tasks. Verbal data and eye-tracking data were collected as indications of students' learning activities. For the verbal data, we applied a fine-grained coding scheme to optimally describe students' learning activities. For the eye-tracking data, we used fixation time and transitions between areas of interest in the process diagrams as indices of learning activities. Various learning activities while studying process diagrams were found that distinguished between more and less successful students. Results showed that between-student variance in comprehension score was highly predicted by meaning making of the process arrows (80%) and fixation time in the main area (65%). Students employed successful learning activities consistently across learning tasks. Furthermore, compared to unsuccessful students, successful students used a more coherent approach of interrelated learning activities for comprehending process diagrams.

  4. Pereskia aculeata Muller (Cactaceae) Leaves: Chemical Composition and Biological Activities.

    PubMed

    Souza, Lucèia Fàtima; Caputo, Lucia; Inchausti De Barros, Ingrid Bergman; Fratianni, Florinda; Nazzaro, Filomena; De Feo, Vincenzo

    2016-01-01

    The aims of this work were to study the chemical composition of the essential oil from the leaves of Pereskia aculeata and to evaluate some biological activities of three leaf extracts. The phenolic content, antioxidant activity, and in vitro antimicrobial and antifungal activities were determined. The methanol extract showed antioxidant activity (EC50 7.09 mg/mL) and high polyphenols content (15.04 ± 0.31 mg gallic acid equivalents (GAE)/g). The petroleum ether extract exhibited potent antibacterial activity against Escherichia coli, whereas the chloroform extract showed inhibitory activity against Bacillus cereus and Staphylococcus aureus. The petroleum ether and methanol extracts were more effective in inhibiting the growth of Aspergillus versicolor. The possible cytotoxicity of extracts on neuroblastoma SH-SY5Y cancer cell line and the influence on adenylate cyclase (ADCY) expression was also studied. P. aculeata chloroform extract showed antiproliferative activity with an IC50 value of 262.83 µg/mL. Treatments of SH-SY5Y neuroblastoma cells with 100 µg/mL of methanol extract significantly reduced ADCY1 expression. PMID:27598154

  5. Inclusion bodies and purification of proteins in biologically active forms.

    PubMed

    Mukhopadhyay, A

    1997-01-01

    Even though recombinant DNA technology has made possible the production of valuable therapeutic proteins, its accumulation in the host cell as inclusion body poses serious problems in the recovery of functionally active proteins. In the last twenty years, alternative techniques have been evolved to purify biologically active proteins from inclusion bodies. Most of these remain only as inventions and very few are commercially exploited. This review summarizes the developments in isolation, refolding and purification of proteins from inclusion bodies that could be used for vaccine and non-vaccine applications. The second section involves a discussion on inclusion bodies, how they are formed, and their physicochemical properties. In vivo protein folding in Escherichia coli and kinetics of in vitro protein folding are the subjects of the third and fourth sections respectively. The next section covers the recovery of bioactive protein from inclusion bodies: it includes isolation of inclusion body from host cell debris, purification in denatured state alternate refolding techniques, and final purification of active molecules. Since purity and safety are two important issues in therapeutic grade proteins, the following three sections are devoted to immunological and biological characterization of biomolecules, nature, and type of impurities normally encountered, and their detection. Lastly, two case studies are discussed to demonstrate the sequence of process steps involved. PMID:8939059

  6. Propolis volatile compounds: chemical diversity and biological activity: a review

    PubMed Central

    2014-01-01

    Propolis is a sticky material collected by bees from plants, and used in the hive as building material and defensive substance. It has been popular as a remedy in Europe since ancient times. Nowadays, propolis use in over-the-counter preparations, “bio”-cosmetics and functional foods, etc., increases. Volatile compounds are found in low concentrations in propolis, but their aroma and significant biological activity make them important for propolis characterisation. Propolis is a plant-derived product: its chemical composition depends on the local flora at the site of collection, thus it offers a significant chemical diversity. The role of propolis volatiles in identification of its plant origin is discussed. The available data about chemical composition of propolis volatiles from different geographic regions are reviewed, demonstrating significant chemical variability. The contribution of volatiles and their constituents to the biological activities of propolis is considered. Future perspectives in research on propolis volatiles are outlined, especially in studying activities other than antimicrobial. PMID:24812573

  7. Gynura procumbens: An Overview of the Biological Activities.

    PubMed

    Tan, Hui-Li; Chan, Kok-Gan; Pusparajah, Priyia; Lee, Learn-Han; Goh, Bey-Hing

    2016-01-01

    Gynura procumbens (Lour.) Merr. (Family Asteraceae) is a medicinal plant commonly found in tropical Asia countries such as China, Thailand, Indonesia, Malaysia, and Vietnam. Traditionally, it is widely used in many different countries for the treatment of a wide variety of health ailments such as kidney discomfort, rheumatism, diabetes mellitus, constipation, and hypertension. Based on the traditional uses of G. procumbens, it seems to possess high therapeutic potential for treatment of various diseases making it a target for pharmacological studies aiming to validate and provide scientific evidence for the traditional claims of its efficacy. Although there has been considerable progress in the research on G. procumbens, to date there is no review paper gathering the reported biological activities of G. procumbens. Hence, this review aims to provide an overview of the biological activities of G. procumbens based on reported in vitro and in vivo studies. In brief, G. procumbens has been reported to exhibit antihypertensive, cardioprotective, antihyperglycemic, fertility enhancement, anticancer, antimicrobial, antioxidant, organ protective, and antiinflammatory activity. The commercial applications of G. procumbens have also been summarized in this paper based on existing patents. The data compiled illustrate that G. procumbens is a potential natural source of compounds with various pharmacological actions which can be utilized for the development of novel therapeutic agents. PMID:27014066

  8. Discovery and biological activity of new chondramides from Chondromyces sp.

    PubMed

    Herrmann, Jennifer; Hüttel, Stephan; Müller, Rolf

    2013-09-01

    Myxobacteria have proven to be highly valuable sources of natural products, as they produce a variety of secondary metabolites with unique structures and often new modes of action. In this study, high-content screening is demonstrated to be a convenient tool for bioactivity-guided isolation of natural products from crude bacterial extracts. By the application of focused, image-based screens we were able to identify over 30 novel chondramide derivatives from Chondromyces sp. MSr9030, some of which were present in only minute amounts. These cyclic depsipeptides were shown to target actin filaments with a similar binding mode to that of the mushroom toxin phalloidin. Fermentations of the myxobacterial strain were carried out under improved cultivation conditions, and supplementation of the culture broth with potassium bromide afforded the production of brominated analogues that are superior (in terms of biological activity) to all chondramides described to date. Initial biological profiling of 11 new derivatives in comparison to the reference compounds (chondramides A-C) showed that bromo-chondramide C3 and propionyl-bromo-chondramide C3 are the most active in cell-based studies, with GI₅₀ values on human cancer cell lines in the low nanomolar range. Given that these brominated C3 analogues were also less potent on noncancerous human cells (by a factor of 2 to 4 in comparison to cancer cell lines), our results can aid further structure-activity relationship-guided development of chondramides, either as molecular probes or pharmaceutical agents. PMID:23959765

  9. Gynura procumbens: An Overview of the Biological Activities

    PubMed Central

    Tan, Hui-Li; Chan, Kok-Gan; Pusparajah, Priyia; Lee, Learn-Han; Goh, Bey-Hing

    2016-01-01

    Gynura procumbens (Lour.) Merr. (Family Asteraceae) is a medicinal plant commonly found in tropical Asia countries such as China, Thailand, Indonesia, Malaysia, and Vietnam. Traditionally, it is widely used in many different countries for the treatment of a wide variety of health ailments such as kidney discomfort, rheumatism, diabetes mellitus, constipation, and hypertension. Based on the traditional uses of G. procumbens, it seems to possess high therapeutic potential for treatment of various diseases making it a target for pharmacological studies aiming to validate and provide scientific evidence for the traditional claims of its efficacy. Although there has been considerable progress in the research on G. procumbens, to date there is no review paper gathering the reported biological activities of G. procumbens. Hence, this review aims to provide an overview of the biological activities of G. procumbens based on reported in vitro and in vivo studies. In brief, G. procumbens has been reported to exhibit antihypertensive, cardioprotective, antihyperglycemic, fertility enhancement, anticancer, antimicrobial, antioxidant, organ protective, and antiinflammatory activity. The commercial applications of G. procumbens have also been summarized in this paper based on existing patents. The data compiled illustrate that G. procumbens is a potential natural source of compounds with various pharmacological actions which can be utilized for the development of novel therapeutic agents. PMID:27014066

  10. Phytochemical concentrations and biological activities of Sorghum bicolor alcoholic extracts.

    PubMed

    Dia, Vermont P; Pangloli, Philipus; Jones, Lynsey; McClure, Angela; Patel, Anjali

    2016-08-10

    Sorghum is an important cereal with reported health benefits. The objectives of this study were to measure the biological activities of alcoholic extracts of ten sorghum varieties and to determine the association between the color of the extracts and their biological activities. Variation on concentrations of bioactives among sorghum varieties was observed with ethanolic extracts giving higher concentrations than methanolic extracts. The color of the extracts significantly correlated with the concentrations of bioactives and with nitric oxide scavenging activity. Freeze-dried ethanol extract is more potent than freeze-dried methanol extract and caused cytotoxicity to A27801AP and PTX-10 OVCA with ED50 values of 0.69 and 1.29 mg mL(-1), respectively. Pre-treatment of OVCA with ethanol extract led to chemosensitization to paclitaxel and the proliferation and colony formation of OVCA cells were reduced by 14.7 to 44.6% and 36.4 to 40.1%, respectively. Sorghum is a potential source of colorants with health promoting properties. This is the first report on the capability of sorghum alcoholic extracts to cause cytotoxicity and chemosensitize ovarian cancer cells in vitro. PMID:27406291

  11. Nanodiamonds as Carriers for Address Delivery of Biologically Active Substances

    PubMed Central

    2010-01-01

    Surface of detonation nanodiamonds was functionalized for the covalent attachment of immunoglobulin, and simultaneously bovine serum albumin and Rabbit Anti-Mouse Antibody. The nanodiamond-IgGI125 and RAM-nanodiamond-BSAI125 complexes are stable in blood serum and the immobilized proteins retain their biological activity. It was shown that the RAM-nanodiamond-BSAI125 complex is able to bind to the target antigen immobilized on the Sepharose 6B matrix through antibody–antigen interaction. The idea can be extended to use nanodiamonds as carriers for delivery of bioactive substances (i.e., drugs) to various targets in vivo. PMID:20672079

  12. Nanodiamonds as Carriers for Address Delivery of Biologically Active Substances.

    PubMed

    Purtov, K V; Petunin, A I; Burov, A E; Puzyr, A P; Bondar, V S

    2010-01-01

    Surface of detonation nanodiamonds was functionalized for the covalent attachment of immunoglobulin, and simultaneously bovine serum albumin and Rabbit Anti-Mouse Antibody. The nanodiamond-IgG(I125) and RAM-nanodiamond-BSA(I125) complexes are stable in blood serum and the immobilized proteins retain their biological activity. It was shown that the RAM-nanodiamond-BSA(I125) complex is able to bind to the target antigen immobilized on the Sepharose 6B matrix through antibody-antigen interaction. The idea can be extended to use nanodiamonds as carriers for delivery of bioactive substances (i.e., drugs) to various targets in vivo. PMID:20672079

  13. Recent developments in biological activities of chalcones: a mini review.

    PubMed

    Singh, Parvesh; Anand, Amit; Kumar, Vipan

    2014-10-01

    Chalcones represent key structural motif in the plethora of biologically active molecules including synthetic and natural products. Synthetic manipulations of chalcones or their isolation from natural sources are being investigated worldwide for the development of more potent and efficient drugs for the treatment of several dreadful diseases such as cancer, diabetes, HIV, tuberculosis, malaria etc. Over the past few years, a large volume of research papers and review articles highlighting the significance of chalcone derivatives has been compiled in the literature. The present review article focuses on the recent developments (2010-2014) on various pharmacological and medicinal aspects of chalcones and their analogues. PMID:25137491

  14. Local or distributed activation? The view from biology

    NASA Astrophysics Data System (ADS)

    Reimers, Mark

    2011-06-01

    There is considerable disagreement among connectionist modellers over whether to represent distinct properties by distinct nodes of a network or whether properties should be represented by patterns of activity across all nodes. This paper draws on the literature of neuroscience to say that a more subtle way of describing how different brain regions contribute to a behaviour, in terms of individual learning and in terms of degrees of importance, may render the current debate moot: both sides of the 'localist' versus 'distributed' debate emphasise different aspects of biology.

  15. Synthesis and biological activity of novel deoxycholic acid derivatives.

    PubMed

    Popadyuk, Irina I; Markov, Andrey V; Salomatina, Oksana V; Logashenko, Evgeniya B; Shernyukov, Andrey V; Zenkova, Marina A; Salakhutdinov, Nariman F

    2015-08-01

    We report the synthesis and biological activity of new semi-synthetic derivatives of naturally occurring deoxycholic acid (DCA) bearing 2-cyano-3-oxo-1-ene, 3-oxo-1(2)-ene or 3-oxo-4(5)-ene moieties in ring A and 12-oxo or 12-oxo-9(11)-ene moieties in ring C. Bioassays using murine macrophage-like cells and tumour cells show that the presence of the 9(11)-double bond associated with the increased polarity of ring A or with isoxazole ring joined to ring A, improves the ability of the compounds to inhibit cancer cell growth. PMID:26037611

  16. Biochemistry of platelet-activating factor: A unique class of biologically active phospholipids

    SciTech Connect

    Snyder, F. )

    1989-01-01

    This brief overview describes the chemical features of this unique bioactive phospholipid that possesses biologic properties identical to platelet-activating factor (PAF) and an antihypertensive polar renal lipid (APRL). The current understanding of PAF metabolism and its regulation are emphasized, particularly in the context of explaining the enzymatic source of PAF in physiologic vs pharmacologic processes. Also included are brief accounts of the biologic properties, structural-functional relationships, antagonists, receptors and mode of action of PAF.

  17. Efficient total syntheses and biological activities of two teixobactin analogues.

    PubMed

    Parmar, Anish; Iyer, Abhishek; Vincent, Charlotte S; Van Lysebetten, Dorien; Prior, Stephen H; Madder, Annemieke; Taylor, Edward J; Singh, Ishwar

    2016-04-26

    The discovery of the new antibiotic teixobactin has been timely in the race for unearthing novel antibiotics wherein the emergence of drug resistant bacteria poses a serious threat worldwide. Herein, we present the total syntheses and biological activities of two teixobactin analogues. This approach is simple, efficient and has several advantages: it uses commercially available building blocks (except AllocHN-d-Thr-OH), has a single purification step and a good recovery (22%). By using this approach we have synthesised two teixobactin analogues and established that the d-amino acids are critical for the antimicrobial activity of these analogues. With continuing high expectations from teixobactin, this work can be regarded as a stepping stone towards an in depth study of teixobactin, its analogues and the quest for synthesising similar molecules. PMID:26984316

  18. Frank Stinchfield Award. Titanium surface with biologic activity against infection.

    PubMed

    Parvizi, Javad; Wickstrom, Eric; Zeiger, Allen R; Adams, Christopher S; Shapiro, Irving M; Purtill, James J; Sharkey, Peter F; Hozack, William J; Rothman, Richard H; Hickok, Noreen J

    2004-12-01

    Despite immense improvements, periprosthetic infection continues to compromise the result of otherwise successful joint arthroplasty. There are various limitations in the treatment of periprosthetic infection, the most important of which is the inability to deliver antibiotics to the local tissue without the need for intravenous administration. We have developed a novel route to covalently tether vancomycin to a metal (titanium) surface, which showed effective bactericidal activity because of a vancomycin coupling. The chemistry of tethering does not affect the biological activity of the biofactors that are attached to the metal surface. This technology holds great promise for the manufacturing of "smart" implants that can be self protective against periprosthetic infection, or can be used for the treatment of periprosthetic infections when they occur. PMID:15577462

  19. Synthesis and biological activity of polyalthenol and pentacyclindole analogues.

    PubMed

    Marcos, Isidro S; Moro, Rosalina F; Costales, Isabel; Basabe, Pilar; Díez, David; Gil, Ana; Mollinedo, Faustino; Pérez-de la Rosa, Fátima; Pérez-Roth, Eduardo; Padrón, José M

    2014-02-12

    A series of indole sesquiterpenes analogues of polyalthenol and pentacyclindole have been synthesized starting from ent-halimic acid in order to test their biological activity. These analogues include diverse oxidation levels at the sesquiterpenyl moiety and different functionalization on the indole ring. All synthetic derivatives were tested against a representative panel of Gram positive and Gram negative bacterial strains, and the human solid tumour cell lines A549 (non-small cell lung), HBL-100 (breast), HeLa (cervix), SW1573 (non-small cell lung), T-47D (breast) and WiDr (colon). Overall, the compounds presented activity against the cancer cell lines. The resulting lead, displaying a polyalthenol scaffold, showed GI50 values in the range 1.2-5.7 μM against all cell lines tested. PMID:24412720

  20. A biologically active peptide mimetic of N-acetylgalactosamine/galactose

    PubMed Central

    Eggink, Laura L; Hoober, J Kenneth

    2009-01-01

    Background Glycosylated proteins and lipids are important regulatory factors whose functions can be altered by addition or removal of sugars to the glycan structure. The glycans are recognized by sugar-binding lectins that serve as receptors on the surface of many cells and facilitate initiation of an intracellular signal that changes the properties of the cells. We identified a peptide that mimics the ligand of an N-acetylgalactosamine (GalNAc)-specific lectin and asked whether the peptide would express specific biological activity. Findings A 12-mer phage display library was screened with a GalNAc-specific lectin to identify an amino acid sequence that binds to the lectin. Phage particles that were eluted from the lectin with free GalNAc were considered to have been bound to a GalNAc-binding site. Peptides were synthesized with the selected sequence as a quadravalent structure to facilitate receptor crosslinking. Treatment of human peripheral blood mononuclear cells for 24 h with the peptide stimulated secretion of interleukin-8 (IL-8) but not of IL-1β, IL-6, IL-10, or tumor necrosis factor-α (TNF-α). The secretion of IL-21 was stimulated as strongly with the peptide as with interferon-γ. Conclusion The data indicate that the quadravalent peptide has biological activity with a degree of specificity. These effects occurred at concentrations in the nanomolar range, in contrast to free sugars that generally bind to proteins in the micro- to millimolar range. PMID:19284521

  1. The biologically active conformations of ligand CCK B receptor

    NASA Astrophysics Data System (ADS)

    Kuznetsov, Pavel E.; Kuznetsova, Nina B.; Schulgin, Sergey V.; Rogacheva, Svetlana M.; Sinyakov, Valeriy V.; Kovtun, Viktor A.

    2006-07-01

    We analyzed literature data about structures of ligands of CCK B receptor. The structure of the binding site (fragments of the third extracellular loop and the seventh transmembrane helix of CCK B receptor) was determined recently by experiments. We were finding presumable biologically active conformations (BAC) of the ligands by two methods. One of them is based on the fact that the most stable conformations of the biologically active peptide on the phase interface "water-lipophilic medium" are often similar to the BAC. Another method is based on the formation of the stable ligand-receptor complex during the modeling procedure. We used Monte-Carlo method with the fixed geometry of the receptor and the optimized geometry of tetrapeptide cholecystokinin (CCK-4). It has been shown, that the first method should be used to find BAC of antagonists of CCK B receptor. The strategy of the formation of the stable ligand-receptor complex during the modeling procedure can be used for the designing of peptide agonists of CCK B receptor.

  2. Metabolic clearance of biologically active luteinizing hormone in man.

    PubMed Central

    Veldhuis, J D; Fraioli, F; Rogol, A D; Dufau, M L

    1986-01-01

    The plasma metabolic clearance of biologically active luteinizing hormone (bioactive LH) was studied using the rat interstitial cell testosterone (RICT) bioassay in six hypogonadotropic men after single bolus injection of highly purified human LH and during continuous steady-state infusions of three graded doses of LH. The LH bolus disappearance curves provided estimates of metabolic clearance rates (MCR) of 24.1 +/- 4.7 (+/- SD) ml/min for bioactive LH vs. 56.2 +/- 12 ml/min for immunoactive LH in the same men (P = 0.03). A lower MCR of bioactive LH compared with immunoactive LH was also observed during continuous infusions of physiological doses of LH; for example, the mean steady-state MCRs for bioactive and immunoactive LH were, respectively, 26.1 +/- 3.1 and 34.2 +/- 3.2 ml/min (P = 0.02). Moreover, the stepped-dose infusion regimens permitted us to demonstrate that increasing doses of pure human LH resulted in progressive and parallel decreases in the apparent MCRs of both bioactive and immunoactive LH. Based on the respective steady-state MCRs calculated at physiological plasma concentrations of immunoactive and bioactive LH, we estimate a mean endogenous production rate for bioactive hormone of 1,937 IU/24 h, and for immunoactive LH of 589 IU/24 h in normal men. These results indicate that previous estimates of LH production rates from immunoassay data alone markedly underestimate the quantity of biologically active hormone secreted in man. PMID:3958184

  3. Synthesis, characterization and biological activities of curcumin nanospheres.

    PubMed

    Arunraj, T R; Sanoj Rejinold, N; Mangalathillam, Sabitha; Saroj, Soumya; Biswas, Raja; Jayakumar, R

    2014-02-01

    Curcumin is one of the most versatile compounds obtained from Curcuma longa. The major obstacle in the therapeutic use of curcumin is its aqueous solubility. To enhance its aqueous solubility and biological activities, we prepared curcumin nanospheres (CNSs) by wet milling-solvent evaporation technique without any surfactants. In this study, we have focused on the synthesis, characterization and biological effects of CNSs. DLS and SEM analyses showed 50-80 nm spherical shaped CNSs with a zeta potential of -31.65 mV. FTIR revealed that there were no structural changes to CNSs. Antibacterial and antifungal studies proved that CNSs were much more effective than curcumin against Escherichia coil, Staphylococcus aureus and Candida albicans. Antioxidant activity of CNSs showed promising result for therapeutic applications. The in vitro anti-inflammatory studies proved that CNSs possessed enhanced anti-inflammatory effect against protein denaturation. Cytotoxicity and uptake of CNSs showed more toxicity on cancer cells (T47D, MG63, A375) sparing normal HDF and IEC cell lines. Skin permeation studies showed CNSs retained at different layers of pig skin. These results give clear evidence for their use against microbial and fungal skin infections as well as cancer treatment. PMID:24738332

  4. Inhalable DNase I microparticles engineered with biologically active excipients.

    PubMed

    Osman, Rihab; Al Jamal, Khuloud T; Kan, Pei-Lee; Awad, Gehanne; Mortada, Nahed; El-Shamy, Abd-Elhameed; Alpar, Oya

    2013-12-01

    Highly viscous mucus poses a big challenge for the delivery of particulates carrying therapeutics to patients with cystic fibrosis. In this study, surface modifying DNase I loaded particles using different excipients to achieve better lung deposition, higher enzyme stability or better biological activity had been exploited. For the purpose, controlled release microparticles (MP) were prepared by co-spray drying DNase I with the polymer poly-lactic-co-glycolic acid (PLGA) and the biocompatible lipid surfactant 1,2-dipalmitoyl-Sn-phosphatidyl choline (DPPC) using various hydrophilic excipients. The effect of the included modifiers on the particle morphology, size, zeta potential as well as enzyme encapsulation efficiency, biological activity and release had been evaluated. Powder aerosolisation performance and particle phagocytosis by murine macrophages were also investigated. The results showed that more than 80% of enzyme activity was recovered after MP preparation and that selected surface modifiers greatly increased the enzyme encapsulation efficiency. The particle morphology was greatly modified altering in turn the powders inhalation indices where dextran, ovalbumin and chitosan hydrochloride increased considerably the respirable fraction compared to the normal hydrophilic carriers lactose and PVP. Despite of the improved aerosolisation caused by chitosan hydrochloride, yet retardation of chitosan coated particles in artificial mucus samples discouraged its application. On the other hand, dextran and polyanions enhanced DNase I effect in reducing cystic fibrosis mucus viscosity. DPPC proved good ability to reduce particles phagocytic uptake even in the presence of the selected adjuvants. The prepared MP systems were biocompatible with lung epithelial cells. To conclude, controlled release DNase I loaded PLGA-MP with high inhalation indices and enhanced mucolytic activity on CF sputum could be obtained by surface modifying the particles with PGA or dextran. PMID

  5. Myricetin: A Dietary Molecule with Diverse Biological Activities

    PubMed Central

    Semwal, Deepak Kumar; Semwal, Ruchi Badoni; Combrinck, Sandra; Viljoen, Alvaro

    2016-01-01

    Myricetin is a common plant-derived flavonoid and is well recognised for its nutraceuticals value. It is one of the key ingredients of various foods and beverages. The compound exhibits a wide range of activities that include strong anti-oxidant, anticancer, antidiabetic and anti-inflammatory activities. It displays several activities that are related to the central nervous system and numerous studies have suggested that the compound may be beneficial to protect against diseases such as Parkinson’s and Alzheimer’s. The use of myricetin as a preserving agent to extend the shelf life of foods containing oils and fats is attributed to the compound’s ability to protect lipids against oxidation. A detailed search of existing literature revealed that there is currently no comprehensive review available on this important molecule. Hence, the present work includes the history, synthesis, pharmaceutical applications and toxicity studies of myricetin. This report also highlights structure-activity relationships and mechanisms of action for various biological activities. PMID:26891321

  6. A biologically active surface enzyme assembly that attenuates thrombus formation

    PubMed Central

    Qu, Zheng; Muthukrishnan, Sharmila; Urlam, Murali K.; Haller, Carolyn A.; Jordan, Sumanas W.; Kumar, Vivek A.; Marzec, Ulla M.; Elkasabi, Yaseen; Lahann, Joerg; Hanson, Stephen R.

    2013-01-01

    Activation of hemostatic pathways by blood-contacting materials remains a major hurdle in the development of clinically durable artificial organs and implantable devices. We postulate that surface-induced thrombosis may be attenuated by the reconstitution onto blood contacting surfaces of bioactive enzymes that regulate the production of thrombin, a central mediator of both clotting and platelet activation cascades. Thrombomodulin (TM), a transmembrane protein expressed by endothelial cells, is an established negative regulator of thrombin generation in the circulatory system. Traditional techniques to covalently immobilize enzymes on solid supports may modify residues contained within or near the catalytic site, thus reducing the bioactivity of surface enzyme assemblies. In this report, we present a molecular engineering and bioorthogonal chemistry approach to site-specifically immobilize a biologically active recombinant human TM fragment onto the luminal surface of small diameter prosthetic vascular grafts. Bioactivity and biostability of TM modified grafts is confirmed in vitro and the capacity of modified grafts to reduce platelet activation is demonstrated using a non-human primate model. These studies indicate that molecularly engineered interfaces that display TM actively limit surface-induced thrombus formation. PMID:23532366

  7. BIOLOGICALLY ACTIVE NATURAL PRODUCTS OF THE GENUS CALLICARPA.

    PubMed

    Jones, William P; Kinghorn, A Douglas

    2008-06-01

    About 20 species from Callicarpa have reported ethnobotanical and ethnomedical uses, and several members of this genus are well known in the traditional medical systems of China and South Asia. Ethnomedical reports indicate their use in the treatment of hepatitis, rheumatism, fever, headache, indigestion, and other ailments. Several species of Callicarpa have been reported to be used against cancer (e.g., Callicarpa americana root to treat skin cancer and Callicarpa rubella bark to treat tumors of the large intestine). Extracts from about 14 species in this genus have been evaluated for biological activity, including antibacterial, antifungal, anti-insect growth, cytotoxic, and phytotoxic activities. In addition to amino acids, benzenoids, simple carbohydrates, and lipids, numerous diterpenes, flavonoids, phenylpropanoids, phytosterols, sesquiterpenes, and triterpenes have been detected in or isolated from the genus Callicarpa. The essential oils of Callicarpa americana have recently been reported to have antialgal and phytotoxic activities, and several isolates from this species (and C. japonica) were identified as contributing to the mosquito bite-deterrent activity that was first indicated by folkloric usage. Recent bioassay-guided investigations of C. americana extracts have resulted in the isolation of several active compounds, mainly of the clerodane diterpene structural type. PMID:19830264

  8. The in vitro biological activity of Lepidium meyenii extracts.

    PubMed

    Valentová, K; Buckiová, D; Kren, V; Peknicová, J; Ulrichová, J; Simánek, V

    2006-03-01

    The biological activity of methanolic and aqueous extracts from dehydrated hypocotyls of Lepidium meyenii (Brassicaceae, vernacular name "maca"), was studied on rat hepatocytes and human breast cancer MCF-7 cells. The extracts did not exhibit cytotoxicity in hepatocyte primary cultures up to 10 mg/ml as measured by the MTT viability test, and lactate dehydrogenase (LDH) and aspartate aminotransferase (AST) leakage. Moreover, after 72 h, extracts inhibited LDH and AST leakage from the hepatocytes. When hepatocytes were intoxicated by t-butyl hydroperoxide, neither extract prevented oxidative damage. Both extracts showed weak antioxidant activity in the DPPH radical scavenging test with IC(50) values of 3.46 +/- 0.16 and 0.71 +/- 0.10 mg/ml, for aqueous and methanolic extracts, respectively. Thus, the observed effect on spontaneous enzyme leakage is probably mediated through mechanisms other than antioxidant activity. Both methanolic and aqueous extracts have shown estrogenic activity comparable with that of silymarin in MCF-7 cell line. Maca estrogenicity was exhibited in the range from 100 to 200 mug of extract per ml. The findings in the present study show that maca does not display in vitro hepatotoxicity. In contrast, a slight cytoprotective effect, probably not mediated by antioxidant capacity, was noted. Maca extracts exhibited estrogenic activity comparably to the effect of silymarin in MCF-7 cells. PMID:16528448

  9. Biological activities of an extract from Cleome viscosa L. (Capparaceae).

    PubMed

    Williams, L A D; Vasques, E; Reid, W; Porter, R; Kraus, W

    2003-10-01

    Electron micrograph examination of the leaf and stem surfaces of Cleome viscosa L (Family Capparaceae) revealed the presence of secretory glandular trichomes with club-cylinder and cylinder morphologies. In the present study, the leaves and stems of C. viscosa were extracted with hexane and the extract was evaluated for the following biological activities: anti-bacterial, anti-fungal, contact insecticidal and nematicidal. The extract was found to be a potent anti-bacterial agent according to the thin layer chromatography autobiographic assay. Activity-directed isolation studies of the anti-bacterially active compounds led to a 14-member ring cembranoid diterpene being identified as one of the effective agents. Minimum inhibitory concentration (MIC) values (microg/spot) of 5.0 microg/spot and 1.0 microg/spot were found for the diterpene on Bacillus subtilis (Gram-positive) and Pseudomonas fluorescens (Gram-negative), respectively. The diterpene did not inhibit the growth of the fungus Cladosporium cucumerinum. The extract demonstrated a pyrethroid type of contact insecticidal activity on adult Cylas formicarius elegantulus Summer (Coleoptera: Curculionidae). The extract also had high nematicidal activity with a percentage Abbott's value of 72.69 on the plant parasitic nematode Meloidogyne incognita Chitwood; however, the extract lost its potency upon subfractionation. PMID:14564407

  10. Hydrolysis of the RNA model substrate catalyzed by a binuclear Zr(IV)-substituted Keggin polyoxometalate.

    PubMed

    Luong, Thi Kim Nga; Absillis, Gregory; Shestakova, Pavletta; Parac-Vogt, Tatjana N

    2015-09-21

    The reactivity and solution behaviour of the binuclear Zr(IV)-substituted Keggin polyoxometalate (Et2NH2)8[{α-PW11O39Zr(μ-OH)(H2O)}2]·7H2O (ZrK 2 : 2) towards phosphoester bond hydrolysis of the RNA model substrate 2-hydroxypropyl-4-nitrophenyl phosphate (HPNP) was investigated at different reaction conditions (pD, temperature, concentration, and ionic strength). The hydrolysis of the phosphoester bond of HPNP, followed by means of (1)H NMR spectroscopy, proceeded with an observed rate constant, kobs = 11.5(±0.42) × 10(-5) s(-1) at pD 6.4 and 50 °C, representing a 530-fold rate enhancement in comparison with the spontaneous hydrolysis of HPNP. (1)H and (31)P NMR spectra indicate that at these reaction conditions the only products of hydrolysis are p-nitrophenol and the corresponding cyclic phosphate ester. The pD dependence of kobs exhibits a bell-shaped profile, with the fastest rate observed at pD 6.4. The formation constant (Kf = 455 M(-1)) and catalytic rate constant (kc = 42 × 10(-5) s(-1)) for the HPNP-ZrK 2 : 2 complex, activation energy (Ea) of 63.35 ± 1.82 kJ mol(-1), enthalpy of activation (ΔH(‡)) of 60.60 ± 2.09 kJ mol(-1), entropy of activation (ΔS(‡)) of -133.70 ± 6.13 J mol(-1) K(-1), and Gibbs activation energy (ΔG(‡)) of 102.05 ± 0.13 kJ mol(-1) at 37 °C were calculated from kinetic experiments. Binding between ZrK 2 : 2 and the P-O bond of HPNP was evidenced by the change in the (31)P chemical shift and signal line-broadening of the (31)P atom in HPNP upon addition of ZrK 2 : 2. Based on (31)P NMR experiments and isotope effect studies, a mechanism for HPNP hydrolysis in the presence of ZrK 2 : 2 was proposed. PMID:26256057

  11. Biological activity of soil contaminated with cobalt, tin, and molybdenum.

    PubMed

    Zaborowska, Magdalena; Kucharski, Jan; Wyszkowska, Jadwiga

    2016-07-01

    In this age of intensive industrialization and urbanization, mankind's highest concern should be to analyze the effect of all metals accumulating in the environment, both those considered toxic and trace elements. With this aim in mind, a unique study was conducted to determine the potentially negative impact of Sn(2+), Co(2+), and Mo(5+) in optimal and increased doses on soil biological properties. These metals were applied in the form of aqueous solutions of Sn(2+) (SnCl2 (.)2H2O), Co(2+) (CoCl2 · 6H2O), and Mo(5+) (MoCl5), each in the doses of 0, 25, 50, 100, 200, 400, and 800 mg kg(-1) soil DM. The activity of dehydrogenases, urease, acid phosphatase, alkaline phosphatase, arylsulfatase, and catalase and the counts of twelve microorganism groups were determined on the 25th and 50th day of experiment duration. Moreover, to present the studied problem comprehensively, changes in the biochemical activity and yield of spring barley were shown using soil and plant resistance indices-RS. The study shows that Sn(2+), Co(2+), and Mo(5+) disturb the state of soil homeostasis. Co(2+) and Mo(5+) proved the greatest soil biological activity inhibitors. The residence of these metals in soil, particularly Co(2+), also generated a drastic decrease in the value of spring barley resistance. Only Sn(2+) did not disrupt its yielding. The studied enzymes can be arranged as follows for their sensitivity to Sn(2+), Co(2+), Mo(5+): Deh > Ure > Aryl > Pal > Pac > Cat. Dehydrogenases and urease may be reliable soil health indicators. PMID:27277093

  12. Biological Activities of Oleanolic Acid Derivatives from Calendula officinalis Seeds.

    PubMed

    Zaki, Ahmed; Ashour, Ahmed; Mira, Amira; Kishikawa, Asuka; Nakagawa, Toshinori; Zhu, Qinchang; Shimizu, Kuniyoshi

    2016-05-01

    Phytochemical examination of butanol fraction of Calendula officinalis seeds led to the isolation of two compounds identified as 28-O-β-D-glucopyranosyl-oleanolic acid 3-O-β-D-glucopyranosyl (1→3)-β-D-glucopyranosiduronic acid (CS1) and oleanolic acid 3-O-β-D-glucopyranosyl (1→3)-β-D-glucopyranosiduronic acid (CS2). Biological evaluation was carried out for these two compounds such as melanin biosynthesis inhibitory, hyaluronic acid production activities, anti obesity using lipase inhibition and adipocyte differentiation as well as evaluation of the protective effect against hydrogen peroxide induced neurotoxicity in neuro-2A cells. The results showed that, compound CS2 has a melanin biosynthesis stimulatory activity; however, compound CS1 has a potent stimulatory effect for the production of hyaluronic acid on normal human dermal fibroblast from adult (NHDF-Ad). Both compounds did not show any inhibitory effect on both lipase and adipocyte differentiation. Compound CS2 could protect neuro-2A cells and increased cell viability against H2 O2 . These activities (melanin biosynthesis stimulatory and protective effect against H2 O2 of CS2 and hyaluronic acid productive activities of these triterpene derivatives) have been reported for the first time. Copyright © 2016 John Wiley & Sons, Ltd. PMID:26887328

  13. Biological Activities of the Essential Oil from Erigeron floribundus.

    PubMed

    Petrelli, Riccardo; Orsomando, Giuseppe; Sorci, Leonardo; Maggi, Filippo; Ranjbarian, Farahnaz; Biapa Nya, Prosper C; Petrelli, Dezemona; Vitali, Luca A; Lupidi, Giulio; Quassinti, Luana; Bramucci, Massimo; Hofer, Anders; Cappellacci, Loredana

    2016-01-01

    Erigeron floribundus (Asteraceae) is an herbaceous plant widely used in Cameroonian traditional medicine to treat various diseases of microbial and non-microbial origin. In the present study, we evaluated the in vitro biological activities displayed by the essential oil obtained from the aerial parts of E. floribundus, namely the antioxidant, antimicrobial and antiproliferative activities. Moreover, we investigated the inhibitory effects of E. floribundus essential oil on nicotinate mononucleotide adenylyltransferase (NadD), a promising new target for developing novel antibiotics, and Trypanosoma brucei, the protozoan parasite responsible for Human African trypanosomiasis. The essential oil composition was dominated by spathulenol (12.2%), caryophyllene oxide (12.4%) and limonene (8.8%). The E. floribundus oil showed a good activity against Staphylococcus aureus (inhibition zone diameter, IZD of 14 mm, minimum inhibitory concentration, MIC of 512 µg/mL). Interestingly, it inhibited the NadD enzyme from S. aureus (IC50 of 98 µg/mL), with no effects on mammalian orthologue enzymes. In addition, T. brucei proliferation was inhibited with IC50 values of 33.5 µg/mL with the essential oil and 5.6 µg/mL with the active component limonene. The essential oil exhibited strong cytotoxicity on HCT 116 colon carcinoma cells with an IC50 value of 14.89 µg/mL, and remarkable ferric reducing antioxidant power (tocopherol-equivalent antioxidant capacity, TEAC = 411.9 μmol·TE/g). PMID:27529211

  14. Catalytically and biologically active silver nanoparticles synthesized using essential oil.

    PubMed

    Vilas, Vidya; Philip, Daizy; Mathew, Joseph

    2014-11-11

    There are numerous reports on phytosynthesis of silver nanoparticles and various phytochemicals are involved in the reduction and stabilization. Pure explicit phytosynthetic protocol for catalytically and biologically active silver nanoparticles is of importance as it is an environmentally benign green method. This paper reports the use of essential oil of Myristica fragrans enriched in terpenes and phenyl propenes in the reduction and stabilization. FTIR spectra of the essential oil and the synthesized biogenic silver nanoparticles are in accordance with the GC-MS spectral analysis reports. Nanosilver is initially characterized by an intense SPR band around 420 nm, followed by XRD and TEM analysis revealing the formation of 12-26 nm sized, highly pure, crystalline silver nanoparticles. Excellent catalytic and bioactive potential of the silver nanoparticles is due to the surface modification. The chemocatalytic potential of nanosilver is exhibited by the rapid reduction of the organic pollutant, para nitro phenol and by the degradation of the thiazine dye, methylene blue. Significant antibacterial activity of the silver colloid against Gram positive, Staphylococcus aureus (inhibition zone--12 mm) and Gram negative, Escherichia coli (inhibition zone--14 mm) is demonstrated by Agar-well diffusion method. Strong antioxidant activity of the biogenic silver nanoparticles is depicted through NO scavenging, hydrogen peroxide scavenging, reducing power, DPPH and total antioxidant activity assays. PMID:24956490

  15. Biological and Nonbiological Antioxidant Activity of Some Essential Oils.

    PubMed

    Pérez-Rosés, Renato; Risco, Ester; Vila, Roser; Peñalver, Pedro; Cañigueral, Salvador

    2016-06-15

    Fifteen essential oils, four essential oil fractions, and three pure compounds (thymol, carvacrol, and eugenol), characterized by gas chromatography and gas chromatography-mass spectrometry, were investigated for biological and nonbiological antioxidant activity. Clove oil and eugenol showed strong DPPH (2,2-diphenyl-1-picrylhydrazyl) free-radical scavenging activity (IC50 = 13.2 μg/mL and 11.7 μg/mL, respectively) and powerfully inhibited reactive oxygen species (ROS) production in human neutrophils stimulated by PMA (phorbol 12-myristate 13-acetate) (IC50 = 7.5 μg/mL and 1.6 μg/mL) or H2O2 (IC50 = 22.6 μg/mL and 27.1 μg/mL). Nutmeg, ginger, and palmarosa oils were also highly active on this test. Essential oils from clove and ginger, as well as eugenol, carvacrol, and bornyl acetate inhibited NO (nitric oxide) production (IC50 < 50.0 μg/mL). The oils of clove, red thyme, and Spanish oregano, together with eugenol, thymol, and carvacrol showed the highest myeloperoxidase inhibitory activity. Isomers carvacrol and thymol displayed a disparate behavior in some tests. All in all, clove oil and eugenol offered the best antioxidant profile. PMID:27214068

  16. Biological Activity and Phytochemical Study of Scutellaria platystegia

    PubMed Central

    Madani mousavi, Seyedeh Neda; Delazar, Abbas; Nazemiyeh, Hossein; Khodaie, Laleh

    2015-01-01

    This study aimed to determine biological activity and phytochemical study of Scutellaria platystegia (family Labiatae). Methanolic (MeOH) extract of aerial parts of S. platystegia and SPE fractions of methanolic extract (specially 20% and 40% methanolic fractions), growing in East-Azarbaijan province of Iran were found to have radical scavenging activity by DPPH (2, 2-diphenyl -1- pycryl hydrazyl) assay. Dichloromethane (DCM) extract of this plant exhibited animalarial activity by cell free method providing IC50 at 1.1876 mg/mL. Crude extracts did not exhibit any toxicity assessed by brine shrimp lethality assay. Phytochemical study of methanolic extract by using reverse phase HPLC method and NMR instrument for isolation and identification of pure compounds respectively, yielded 2-(4- hydroxy phenyl) ethyl-O-β-D- glucopyranoside from 10% and apigenin 7-O-glucoside, verbascoside and martynoside from 40% SPE fraction. Occurance of verbascoside and martynoside as biochemical markers appeared to be widespread in this genus. Antioxidant and antimalarial activity of MeOH and DCM extracts, respectively, as well as no general toxicity of them could provide a basis for further in-vitro and in-vivo studies and clinical trials to develop new therapeutical alternatives. PMID:25561927

  17. [The biological activity of macrophages in health and disease].

    PubMed

    Nazimek, Katarzyna; Bryniarski, Krzysztof

    2012-01-01

    Macrophages are involved in immune response as phagocytes, antigen presenting cells and as effector cells of delayed-type hypersensitivity. Moreover, the activity of macrophages is associated with modulation of many biological processes during the whole life and depends on the actual macrophage phenotype induced under the influence of various microenvironmental stimuli. In pregnancy, placental macrophages induce the development of maternal tolerance to fetal antigens, while fetal macrophages are responsible for proper formation of tissues and organs. Residual macrophages play a very important role in tissue homeostasis, apoptotic cell clearance to prevent autoimmunization and first defense in infections. The inflammatory response of macrophages may be modulated by pathogens. Their suppressive activity is observed in immunologically privileged organs such as testes. In pathologies, macrophages are responsible for tissue damage in a case of nonspecific activation followed by overproduction of proinflammatory factors. Suppression of a specific immune response against tumors is mainly the effect of tumor associated macrophage (TAM) action. On the other hand, presentation of allergens or self-antigens by macrophages and their nonspecific activation by necrotic adipocytes leads to the induction of a chronic inflammatory response and impairment of immunity. Therefore, modulation of macrophage functions may be the key for improvement of therapy of cancer and allergic, autoimmune, metabolic, cardiovascular and Alzheimer's diseases. PMID:22922151

  18. In vitro biological activities of alkaloids from Cryptolepis sanguinolenta.

    PubMed

    Cimanga, K; De Bruyne, T; Lasure, A; Van Poel, B; Pieters, L; Claeys, M; Berghe, D V; Kambu, K; Tona, L; Vlietinck, A J

    1996-02-01

    In our biological screening of higher plants, an aqueous and an 80% EtOH extract from the root bark of Cryptolepis sanguinolenta showed potent antibacterial, anticomplementary, and moderate antiviral activities, but no antifungal effect could be detected. Bioassay-guided fractionation of the 80% EtOH extract led to the isolation of three alkaloids: quindoline (1), hydroxycryptolepine (2), cryptolepine.HCl (3), and the corresponding base cryptolepine (4). All compounds strongly inhibited the growth of Gram-positive bacteria (MIC < or = 100 micrograms/ml) and showed a moderate (MIC = 125 or 250 micrograms/ml), a weak (MIC = 500 micrograms/ml), or no activity (MIC > 500 micrograms/ml) against selected Gram-negative bacteria. They also possessed a bactericidal effect depending on the bacterial strain. Compounds 1, 2 and 3 displayed a dose-dependent inhibitory effect on the classical pathway of the complement system while compounds 2 and 3 activated the alternative pathway, except for compound 1. Compound 3 was found to possess an antiherpetic activity. Compounds 1 and 4 showed no antiviral effect, but were quite cytotoxic in the antiviral test system down to a concentration of 1 microgram/ml. PMID:8720383

  19. Synthesis and biological activities of new hydrazide derivatives.

    PubMed

    Ozdemir, Ahmet; Turan-Zitouni, Gulhan; Kaplancikli, Zafer Asim; Tunali, Yağmur

    2009-06-01

    The synthesis of a new series of imidazo[1,2-a]pyrazine-2-carboxylic acid arylidene-hydrazides is described. The chemical structures of the compounds were elucidated by IR, (1)H-NMR, FAB(+)-MS spectral data. Their biological activity against various bacteria, fungi species, and Mycobacterium tuberculosis was investigated. Antibacterial activity was measured against Escherichia coli (NRRL B-3704), Staphylococcus aureus (NRRL B-767), Salmonella typhimurium (NRRL B-4420), Proteus vulgaris (NRLL B-123), Enterococcus faecalis (isolated obtained from Faculty of Medicine Osmangazi University, Eskisehir, Turkey), Pseudomonas aeruginosa (NRRL B-23 27853), Klebsiella spp. (isolated obtained from Faculty of Medicine Osmangazi University, Eskisehir, Turkey), while antifungal activity was evaluated against Candida albicans (isolates obtained from Osmangazi Uni. Fac.of Medicine), Candida glabrata (isolates obtained from Osmangazi Uni. Fac.of Medicine). Compounds were also evaluated for antituberculosis activity against Mycobacterium tuberculosis H(37)Rv using the BACTEC 460 radiometric system and BACTEC 12B medium. The compounds showed moderate inhibitor effects against human pathogenic microorganisms., whereas the preliminary results indicated that all of the tested compounds were inactive against Mycobacterium tuberculosis H(37)Rv. PMID:18825530

  20. Catalytically and biologically active silver nanoparticles synthesized using essential oil

    NASA Astrophysics Data System (ADS)

    Vilas, Vidya; Philip, Daizy; Mathew, Joseph

    2014-11-01

    There are numerous reports on phytosynthesis of silver nanoparticles and various phytochemicals are involved in the reduction and stabilization. Pure explicit phytosynthetic protocol for catalytically and biologically active silver nanoparticles is of importance as it is an environmentally benign green method. This paper reports the use of essential oil of Myristica fragrans enriched in terpenes and phenyl propenes in the reduction and stabilization. FTIR spectra of the essential oil and the synthesized biogenic silver nanoparticles are in accordance with the GC-MS spectral analysis reports. Nanosilver is initially characterized by an intense SPR band around 420 nm, followed by XRD and TEM analysis revealing the formation of 12-26 nm sized, highly pure, crystalline silver nanoparticles. Excellent catalytic and bioactive potential of the silver nanoparticles is due to the surface modification. The chemocatalytic potential of nanosilver is exhibited by the rapid reduction of the organic pollutant, para nitro phenol and by the degradation of the thiazine dye, methylene blue. Significant antibacterial activity of the silver colloid against Gram positive, Staphylococcus aureus (inhibition zone - 12 mm) and Gram negative, Escherichia coli (inhibition zone - 14 mm) is demonstrated by Agar-well diffusion method. Strong antioxidant activity of the biogenic silver nanoparticles is depicted through NO scavenging, hydrogen peroxide scavenging, reducing power, DPPH and total antioxidant activity assays.

  1. Chemistry and Biological Activities of Flavonoids: An Overview

    PubMed Central

    Kumar, Shashank; Pandey, Abhay K.

    2013-01-01

    There has been increasing interest in the research on flavonoids from plant sources because of their versatile health benefits reported in various epidemiological studies. Since flavonoids are directly associated with human dietary ingredients and health, there is need to evaluate structure and function relationship. The bioavailability, metabolism, and biological activity of flavonoids depend upon the configuration, total number of hydroxyl groups, and substitution of functional groups about their nuclear structure. Fruits and vegetables are the main dietary sources of flavonoids for humans, along with tea and wine. Most recent researches have focused on the health aspects of flavonoids for humans. Many flavonoids are shown to have antioxidative activity, free radical scavenging capacity, coronary heart disease prevention, hepatoprotective, anti-inflammatory, and anticancer activities, while some flavonoids exhibit potential antiviral activities. In plant systems, flavonoids help in combating oxidative stress and act as growth regulators. For pharmaceutical purposes cost-effective bulk production of different types of flavonoids has been made possible with the help of microbial biotechnology. This review highlights the structural features of flavonoids, their beneficial roles in human health, and significance in plants as well as their microbial production. PMID:24470791

  2. Colloidal mesoporous silica nanoparticles enhance the biological activity of resveratrol.

    PubMed

    Summerlin, Natalie; Qu, Zhi; Pujara, Naisarg; Sheng, Yong; Jambhrunkar, Siddharth; McGuckin, Michael; Popat, Amirali

    2016-08-01

    The naturally occurring polyphenol resveratrol (RES) has attracted increasing attention in recent years due to its antioxidant, anti-inflammatory, and anticancer activity. However, resveratrol's promising potential as a nutraceutical is hindered by its poor aqueous solubility, which limits its biological activity. Here we show that encapsulating resveratrol in colloidal mesoporous silica nanoparticles (MCM-48-RES) enhances its saturated solubility by ∼95% and increases its in vitro release kinetics compared to pure resveratrol. MCM-48-RES showed high loading capacity (20% w/w) and excellent encapsulation efficiency (100%). When tested against HT-29 and LS147T colon cancer cell lines, MCM-48-RES-mediated in vitro cell death was higher than that of pure resveratrol, mediated via the PARP and cIAP1 pathways. Finally, MCM-48-RES treatment also inhibited lipopolysaccharide-induced NF-κB activation in RAW264.7 cells, demonstrating improved anti-inflammatory activity. More broadly, our observations demonstrate the potential of colloidal mesoporous silica nanoparticles as next generation delivery carriers for hydrophobic nutraceuticals. PMID:27060664

  3. Processed Vietnamese ginseng: Preliminary results in chemistry and biological activity

    PubMed Central

    Le, Thi Hong Van; Lee, Seo Young; Kim, Tae Ryong; Kim, Jae Young; Kwon, Sung Won; Nguyen, Ngoc Khoi; Park, Jeong Hill; Nguyen, Minh Duc

    2013-01-01

    Background This study was carried out to investigate the effect of the steaming process on chemical constituents, free radical scavenging activity, and antiproliferative effect of Vietnamese ginseng. Methods Samples of powdered Vietnamese ginseng were steamed at 120°C for various times and their extracts were subjected to chemical and biological studies. Results Upon steaming, contents of polar ginsenosides, such as Rb1, Rc, Rd, Re, and Rg1, were rapidly decreased, whereas less polar ginsenosides such as Rg3, Rg5, Rk1, Rk3, and Rh4 were increased as reported previously. However, ocotillol type saponins, which have no glycosyl moiety at the C-20 position, were relatively stable on steaming. The radical scavenging activity was increased continuously up to 20 h of steaming. Similarly, the antiproliferative activity against A549 lung cancer cells was also increased. Conclusion It seems that the antiproliferative activity is closely related to the contents of ginsenoside Rg3, Rg5, and Rk1. PMID:24748840

  4. Phenoxy-bridged binuclear Zn(II) complex holding salen ligand: Synthesis and structural characterization

    NASA Astrophysics Data System (ADS)

    Azam, Mohammad; Al-Resayes, Saud I.

    2016-03-01

    A novel binuclear phenoxo-bridged zinc complex obtained from the interaction of ligand, 2,2-(1E,1E)-(2,2-dimethylpropane-1,3-diyl)bis(azanylylidene) bis(methanylylidene)diphenol with zinc chloride is reported. The synthesized and isolated zinc complex has been characterized by FT-IR, 1H- and 13C- NMR, ESI-MS, TGA/DTA and single crystal X-ray diffraction studies. The phenoxo-bridge in this binuclear Zn(II) complex is due to the phenolic oxygen of the salen liagnd. The complex crystallizes in monoclinic P-1 space group, and different geometry has been assigned for both zinc ions in the complex.

  5. Diastereoselective Synthesis of Biologically Active Cyclopenta[b]indoles.

    PubMed

    Santos, Marilia S; Fernandes, Daniara C; Rodrigues, Manoel T; Regiani, Thais; Andricopulo, Adriano D; Ruiz, Ana Lúcia T G; Vendramini-Costa, Débora B; de Carvalho, João E; Eberlin, Marcos N; Coelho, Fernando

    2016-08-01

    The cyclopenta[b]indole motif is present in several natural and synthetic biologically active compounds, being directly responsible for the biological effects some of them present. We described herein a three step sequence for the synthesis of cyclopenta[b]indoles with a great structural diversity. The method is based on an oxidative Michael addition of suitable indoles on the double bond of Morita-Baylis-Hillman adducts mediated by a hypervalent iodine reagent (IBX) to form β-ketoesters, which were chemoselectively reduced with NaBH4 in THF to give the corresponding β-hydroxy-esters. The diastereoisomeric mixture was then treated with a catalytic amount of triflic acid (20 mol %) to give cyclopenta[b]indoles with overall yields ranging from 8 to 73% (for 2 steps). The acid-catalyzed cyclization step gave the required heterocycles, via an intramolecular Friedel-Crafts reaction, with high diastereoselectivity, where only the trans product was observed. A mechanistic study monitored by ESI-(+)-MS was also conducted to collect evidence about the mechanism of this reaction. The new molecules herein synthesized were also evaluated against a panel of human cancer cells demonstrating a promising antitumoral profile. PMID:27403650

  6. Biological surface-active compounds from marine bacteria.

    PubMed

    Dang, Nga Phuong; Landfald, Bjarne; Willassen, Nils Peder

    2016-01-01

    Surface-active compounds (SACs) are widely used in different industries as well as in many daily consumption products. However, with the increasing concern for their environmental acceptability, attention has turned towards biological SACs which are biodegradable, less toxic and more environmentally friendly. In this work, 176 marine hydrocarbon-degrading bacterial isolates from petroleum-contaminated sites along the Norwegian coastline were isolated and screened for their capacity to produce biological SACs. Among them, 18 isolates were capable of reducing the surface tension of the culture medium by at least 20 mN m(-1) and/or capable of maintaining more than 40% of the emulsion volume after 24 h when growing on glucose or kerosene as carbon and energy source. These isolates were members of the genera Pseudomonas, Pseudoalteromonas, Rhodococcus, Catenovulum, Cobetia, Glaciecola, Serratia, Marinomonas and Psychromonas. Two isolates, Rhodococcus sp. LF-13 and Rhodococcus sp. LF-22, reduced surface tension of culture medium by more than 40 mN m(-1) when growing on kerosene, n-hexadecane or rapeseed oil. The biosurfactants were produced by resting cells of the two Rhodococcus strains suggesting the biosynthesis of the biosurfactants was not necessarily associated with their growth on hydrocarbons. PMID:26506920

  7. Residual matrix from different separation techniques impacts exosome biological activity

    PubMed Central

    Paolini, Lucia; Zendrini, Andrea; Noto, Giuseppe Di; Busatto, Sara; Lottini, Elisabetta; Radeghieri, Annalisa; Dossi, Alessandra; Caneschi, Andrea; Ricotta, Doris; Bergese, Paolo

    2016-01-01

    Exosomes are gaining a prominent role in research due to their intriguing biology and several therapeutic opportunities. However, their accurate purification from body fluids and detailed physicochemical characterization remain open issues. We isolated exosomes from serum of patients with Multiple Myeloma by four of the most popular purification methods and assessed the presence of residual contaminants in the preparations through an ad hoc combination of biochemical and biophysical techniques - including Western Blot, colloidal nanoplasmonics, atomic force microscopy (AFM) and scanning helium ion microscopy (HIM). The preparations obtained by iodixanol and sucrose gradients were highly pure. To the contrary, those achieved with limited processing (serial centrifugation or one step precipitation kit) resulted contaminated by a residual matrix, embedding the exosomes. The contaminated preparations showed lower ability to induce NfkB nuclear translocation in endothelial cells with respect to the pure ones, probably because the matrix prevents the interaction and fusion of the exosomes with the cell membrane. These findings suggest that exosome preparation purity must be carefully assessed since it may interfere with exosome biological activity. Contaminants can be reliably probed only by an integrated characterization approach aimed at both the molecular and the colloidal length scales. PMID:27009329

  8. Experimental and theoretical studies of hydrolysis of nerve agent sarin by binuclear zinc biomimetic catalysts

    NASA Astrophysics Data System (ADS)

    Guo, Nan; Zhong, Jin-Yi; Chen, Shi-Lu; Liu, Jing-Quan; Min, Qi; Shi, Rui-Xue

    2015-08-01

    A complex (ZnL1) of 2,2-(2-hydroxy-5-methyl-1,3-phenylene)bis(methylene)bis ((pyridin-2-ylmethyl)azanediyl)diethanol (this ligand is named by L1) functionalized with two Zn(II) centers, has been previously suggested to be a structural model for binuclear zinc phosphotriesterases (PTEs) and proven to be an effective catalyst for the hydrolysis of bis(2,4-dinitrophenyl)phosphate (BDNPP). In this paper, ZnL1 was further found to have a high catalytic activity for the hydrolysis of isopropyl methylphosphonofluoridate (sarin, GB) with kcat/Km = 0.051 s-1 M-1 at 303 K, examined by on-site NMR analysis. The subsequent density functional theory (DFT) calculations indicate that a terminal alkoxide (Ot) bound by Zn may work as a general base to activate a water molecule and then a hydroxide derived from the latter performs the initial nucleophilic attack on the phosphor in GB. Inspired by this mechanism, a new biomimetic catalyst was designed and synthesized by replacing the two pyridines of ZnL1 by hydroxyls, i.e. a complex of two Zn(II) with 2,6-bis((bis(2-hydroxyethyl)amino)methyl)-4-methylphenol (the ligand is named by L2). This replacement was expected to increase the Ot basicity, thereby facilitating the nucleophilic attack and the overall hydrolysis of GB. It was shown that ZnL2 had a very high catalytic efficiency for the hydrolysis of GB, with kcat/Km = 0.11 s-1 M-1 at 303 K and about 90% conversion in 30 min. The following DFT calculations proposed a detailed reaction mechanism of ZnL2 and gave an energy barrier (5.8 kcal M-1) very close to the experimental activation energy (5.6 kcal M-1). In this study, a mechanism-inspired design strategy has been demonstrated to be successful in developing biomimetic catalyst.

  9. [The release of biologically active compounds from peat peloids].

    PubMed

    Babaskin, D V

    2011-01-01

    This work had the objective to study kinetics of the release of flavonoides from peat peloid compositions containing extracts of medicinal herbs in model systems.The key parameters of the process are defined. The rate of liberation of flavonoides is shown to depend on their initial concentration in the compositions being used. The influence of the flavonoide composition of the tested extracts and dimethylsulfoxide on the release of biologically active compounds contained in the starting material in the model environment is estimated. The possibility of the layer-by-layer deposition of the compositions and peat peloids in order to increase the efficacy of flavonoide release from the starting composition and to ensure more rational utilization of the extracts of medicinal plants is demonstrated. PMID:22165149

  10. Macrophage activation syndrome in the era of biologic therapy.

    PubMed

    Grom, Alexei A; Horne, AnnaCarin; De Benedetti, Fabrizio

    2016-05-01

    Macrophage activation syndrome (MAS) refers to acute overwhelming inflammation caused by a 'cytokine storm'. Although increasingly recognized as a life-threatening complication of various rheumatic diseases, clinically, MAS is strikingly similar to primary and secondary forms of haemophagocytic lymphohistiocytosis (HLH). Not surprisingly, many rheumatologists prefer the term secondary HLH rather than MAS to describe this condition, and efforts to change the nomenclature are in progress. The pathophysiology of MAS remains elusive, but observations in animal models, as well as data on the effects of new anticytokine therapies on rates and clinical presentations of MAS in patients with systemic juvenile idiopathic arthritis (sJIA), provide clues to the understanding of this perplexing clinical phenomenon. In this Review, we explore the latest available evidence and discuss potential diagnostic challenges in the era of increasing use of biologic therapies. PMID:27009539

  11. Advances in preparation, analysis and biological activities of single chitooligosaccharides.

    PubMed

    Li, Kecheng; Xing, Ronge; Liu, Song; Li, Pengcheng

    2016-03-30

    Chitooligosaccharides (COS), as a source of potential bioactive material, has been reported to possess diverse bioactivities. These bioactivities of COS are often tested using relatively poorly characterized oligomer mixtures during past few decades, resulting in difficult identification of COS molecules responsible for biological effects. Therefore, a new interest has recently been emerged on highly purified COS of defined size. Several technological approaches have been used to produce single COS and new improvements were introduced to their characterization in order to understand the unrevealed structure-function relationship. Here we provide an overview of techniques that were used to prepare and analyze reasonably well-defined COS fractions. Based on the latest reports, several applications of single COS for plants and animals, are also presented, including antitumor, immunostimulatory, antioxidant, antimicrobial, elicitors of plant defence and neural activity. PMID:26794961

  12. Inactivation efficiencies of radical reactions with biologically active DNA

    NASA Astrophysics Data System (ADS)

    Lafleur, M. V. M.; Retèl, J.; Loman, H.

    Dilute aqueous solutions of biologically active θX174 DNA may serve as a simplified model system of the cell. Damage to the DNA after irradiation with γ-rays, may be ascribed to reactions with .OH, .H and e -aq or secondary radicals, arising from reactions of water radicals with added scavengers. Conversion of primary (water) radicals into secondary (scavenger) radicals leads to a considerable protection of the DNA, which, however, would have been larger if these secondary radicals did not contribute to DNA inactivation. The inactivation yield due to isopropanol or formate (secondary) radicals depends on dose rate as well as DNA concentration. Furthermore the inactivation efficiencies of the reactions of both the primary and the secondary radicals with single-stranded DNA could be established.

  13. Fungal phytotoxins with potential herbicidal activity: chemical and biological characterization.

    PubMed

    Cimmino, Alessio; Masi, Marco; Evidente, Marco; Superchi, Stefano; Evidente, Antonio

    2015-12-19

    Covering: 2007 to 2015 Fungal phytotoxins are secondary metabolites playing an important role in the induction of disease symptoms interfering with host plant physiological processes. Although fungal pathogens represent a heavy constraint for agrarian production and for forest and environmental heritage, they can also represent an ecofriendly alternative to manage weeds. Indeed, the phytotoxins produced by weed pathogenic fungi are an efficient tool to design natural, safe bioherbicides. Their use could avoid that of synthetic pesticides causing resistance in the host plants and the long term impact of residues in agricultural products with a risk to human and animal health. The isolation and structural and biological characterization of phytotoxins produced by pathogenic fungi for weeds, including parasitic plants, are described. Structure activity relationships and mode of action studies for some phytotoxins are also reported to elucidate the herbicide potential of these promising fungal metabolites. PMID:26443032

  14. Production of biologically active recombinant human lactoferrin in Aspergillus oryzae.

    PubMed

    Ward, P P; Lo, J Y; Duke, M; May, G S; Headon, D R; Conneely, O M

    1992-07-01

    We report the production of recombinant human lactoferrin in Aspergillus oryzae. Expression of human lactoferrin (hLF), a 78 kD glycoprotein, was achieved by placing the cDNA under the control of the A. oryzae alpha-amylase promoter and the 3' flanking region of the A. niger glucoamylase gene. Using this system, hLF is expressed and secreted into the growth medium at levels up to 25 mg/l. The recombinant lactoferrin is indistinguishable from human milk lactoferrin with respect to its size, immunoreactivity, and iron-binding capacity. The recombinant protein appears to be appropriately N-linked glycosylated and correctly processed at the N-terminus by the A. oryzae secretory apparatus. Lactoferrin is the largest heterologous protein and the first mammalian glycoprotein expressed in the Aspergillus system to date. Hence, this expression system appears suitable for the large-scale production and secretion of biologically active mammalian glycoproteins. PMID:1368268

  15. Production and biological activities of yellow pigments from Monascus fungi.

    PubMed

    Chen, Gong; Wu, Zhenqiang

    2016-08-01

    Monascus yellow pigments (MYPs), are azaphilone compounds and one of the three main components of total Monascus pigments (MPs). Thirty-five hydrophilic or hydrophobic MYPs have been identified, with the majority being hydrophobic. Apart from screening special Monascus strains, some advanced approaches, such as extractive and high-cell-density fermentations, have been applied for developing or producing new MYPs, especially extracellular hydrophilic MYPs. The outstanding performance of MYPs in terms of resistance to photodegradation, as well as tolerance for temperature and pH, give natural MYPs reasonable prospects, compared with the orange and red MPs, for practical use in the present and future. Meanwhile, MYPs have shown promising potential for applications in the food and pharmaceutical industries based on their described bioactivities. This review briefly summarizes the reports to date on chemical structures, biological activities, biosynthetic pathways, production technologies, and physicochemical performances of MYPs. The existing problems for MYPs are discussed and research prospects proposed. PMID:27357404

  16. Threading moieties play a significant role in determining the DNA binding properties of binuclear ruthenium complexes

    NASA Astrophysics Data System (ADS)

    Paramanathan, Thayaparan; Clark, Andrew; Westerlund, Fredrik; Lincoln, Per; McCauley, Micah J.; Rouzina, Ioulia; Williams, Mark C.

    2015-03-01

    Binuclear ruthenium complexes are of interest due to their selective DNA binding properties, which make them potential candidates for chemotherapy. These dumbbell shaped molecules have to thread through the DNA base pairs to reach their final threaded intercalation state. Here we study the binuclear ruthenium complex, ΔΔ -[ μ-bidppz(bpy)4Ru2]4+ and compare it with the previously studied ΔΔ -[ μ-bidppz(phen)4Ru2]4+. Both have the same intercalating bridge unit, but different threading moieties. In this study, we stretch a single DNA molecule held with optical tweezers in the presence of the ligand at various concentrations and hold the DNA at constant force until an equilibrium DNA elongation is reached. The extension of the DNA obtained as a function of time during binding yields the kinetics and equilibrium binding properties of the ligand. The preliminary data suggests that the binuclear complex with bpy in the threading moiety shows stronger affinity and an order of magnitude faster on rate, compared to its counterpart with phen in the threading moiety. This confirms the hypothesis that the extra aromatic ring of phen interferes with the threading intercalation process.

  17. Biological activities of carbohydrate-branched chitosan derivatives.

    PubMed

    Morimoto, M; Saimoto, H; Usui, H; Okamoto, Y; Minami, S; Shigemasa, Y

    2001-01-01

    Two types of biological activities of the carbohydrate-branched chitosan derivatives were investigated. One is the specific interaction with lectins and bacterium. The other is activation of canine polymorphonuclear leukocyte (PMN) cells. The specific bindings of the L-fucose-branched chitosan derivative with Ulex europaeus agglutinin I (UEA-I) and the N-acetyl-D-glucosamine-branched chitosan derivative with Concanavalin A (Con A) were confirmed by a surface plasmon resonance technique. The specific aggregation of the fluorescence-labeled L-fucose-branched chitosan derivative with Pseudomonas aeruginosa was observed by fluorescent microscopic observation. The aggregation would be attributed to the specific binding between the L-fucose-branched chitosan derivative and PA-II receptor on the cell surface of P. aeruginosa. The influence of the chitosan derivatives on the active oxygen species generation from canine PMN cells was also investigated by the luminol-aided chemiluminescence method. The chemiluminescence responses depended on the degree of substitution and water solubility of the chitosan derivatives. The water-insoluble chitosan derivatives would stimulate the PMN cells by a phagocytosis mechanism, and the water-soluble ones would sensitize the PMN cells by a priming mechanism. PMID:11777384

  18. Differential Biological Activities of Swine Interferon-α Subtypes.

    PubMed

    Zanotti, Cinzia; Razzuoli, Elisabetta; Crooke, Helen; Soule, Olubukola; Pezzoni, Giulia; Ferraris, Monica; Ferrari, Angelo; Amadori, Massimo

    2015-12-01

    Interferons (IFNs) play a crucial role in the host's immune response and other homeostatic control actions. Three IFN types and several IFN families within the types allow for a plethora of regulatory actions. The number of distinct IFN molecules is highest among type I IFNs and, in particular, within the IFN-α family. In pigs, there are 17 IFN-α subtypes with different antiviral activities and different expression profiles; however, no data are available about biological properties other than the antiviral effector activities. Therefore, 16 porcine IFN-α genes were cloned, expressed in mammalian Chinese hamster ovary cells, and characterized for antiviral, anti-inflammatory, and MHC-modulating activities at a pre-established level of 10 IU/mL. Antiviral activity: IFN-α2, -α5, -α9, and -α10 showed the highest level of activity in a pseudorabies virus yield reduction assay. On the contrary, little, if any, activity was shown by IFN-α3, -α7, -α13, -α4, and -α15. Anti-inflammatory activity: With the exception of IFNs-α2, -α7, -α9, and -α11, all IFN-α subtypes had significant anti-inflammatory control activity in an interleukin-8 (IL-8) yield reduction assay. Gene expression analyses showed that some IFN-α subtypes can significantly downregulate the expression of IL-8, tumor necrosis factor α (TNF-α), IL-6, Toll-like receptor 4 (TLR4), βD1, and nuclear factor-κB (NF-kB) genes, while maintaining or upregulating the expression of βD4. Immunomodulation: A significant upregulation of class I and/or class II MHC was induced by all the IFNs under study, with the exception of IFNs-α11, -α15, and -α16, which instead significantly downregulated class I MHC. Our results indicate that gene duplications in the porcine IFN-α family underlie diverse effector and regulatory activities, being therefore instrumental in host survival and environmental adaptation. This role of IFN-α could be founded on fine-tuning and regulation of pro- and anti

  19. Dynamic properties of biologically active synthetic heparin-like hexasaccharides.

    PubMed

    Angulo, Jesús; Hricovíni, Milos; Gairi, Margarida; Guerrini, Marco; de Paz, José Luis; Ojeda, Rafael; Martín-Lomas, Manuel; Nieto, Pedro M

    2005-10-01

    A complete study of the dynamics of two synthetic heparin-like hexasaccharides, D-GlcNHSO3-6-SO4-alpha-(1-->4)-L-IdoA-2-SO4-alpha-(1-->4)-D-GlcNHSO3-6-SO4-alpha-(1-->4)-L-IdoA-2-SO4-alpha-(1-->4)-D-GlcNHSO3-6-SO4-alpha-(1-->4)-L-IdoA-2-SO4-alpha-1-->iPr (1) and -->4)-L-IdoA-2-SO4-alpha-(1-->4)-D-GlcNHAc-6-SO4-alpha-(1-->4)-L-IdoA-alpha-(1-->4)-D-GlcNHSO3-alpha-(1-->4)-L-IdoA-2-SO4-alpha-1-->iPr (2), has been performed using 13C-nuclear magnetic resonance (NMR) relaxation parameters, T1, T2, and heteronuclear nuclear Overhauser effect (NOEs). Compound 1 is constituted from sequences corresponding to the major polysaccharide heparin region, while compound 2 contains a sequence never found in natural heparin. They differ from each other only in sulphation patterns, and are capable of stimulating fibroblast growth factors (FGFs)-1 induced mitogenesis. Both oligosaccharides exhibit a remarkable anisotropic overall motion in solution as revealed by their anisotropic ratios (tau /tau||), 4.0 and 3.0 respectively. This is a characteristic behaviour of natural glycosaminoglycans (GAG) which has also been observed for the antithrombin (AT) binding pentasaccharide D-GlcNHSO3-6-SO4-alpha-(1-->4)-D-GlcA-beta-(1-->4)-D-GlcNHSO3-(3,6-SO4)-alpha-(1-->4)-L-IdoA-2-SO4-alpha-(1-->4)-D-GlcNHSO3-6-SO4-alpha-1-->Me (3) (Hricovíni, M., Guerrini, M., Torri, G., Piani, S., and Ungarelli, F. (1995) Conformational analysis of heparin epoxide in aqueous solution. An NMR relaxation study. Carbohydr. Res., 277, 11-23). The motional properties observed for 1 and 2 provide additional support to the suitability of these compounds as heparin models in agreement with previous structural (de Paz, J.L., Angulo, J., Lassaletta, J.M., Nieto, P.M., Redondo-Horcajo, M., Lozano, R.M., Jiménez-Gallego, G., and Martín-Lomas, M. (2001) The activation of fibroblast growth factors by heparin: synthesis, structure and biological activity of heparin-like oligosaccharides. Chembiochem, 2, 673-685; Ojeda, R

  20. Phytochemical Analysis and Biological Activities of Cola nitida Bark

    PubMed Central

    Dah-Nouvlessounon, Durand; Adoukonou-Sagbadja, Hubert; Diarrassouba, Nafan; Sina, Haziz; Adjanohoun, Adolphe; Inoussa, Mariam; Akakpo, Donald; Gbenou, Joachim D.; Kotchoni, Simeon O.; Dicko, Mamoudou H.; Baba-Moussa, Lamine

    2015-01-01

    Kola nut is chewed in many West African cultures and is used ceremonially. The aim of this study is to investigate some biological effects of Cola nitida's bark after phytochemical screening. The bark was collected, dried, and then powdered for the phytochemical screening and extractions. Ethanol and ethyl acetate extracts of C. nitida were used in this study. The antibacterial activity was tested on ten reference strains and 28 meat isolated Staphylococcus strains by disc diffusion method. The antifungal activity of three fungal strains was determined on the Potato-Dextrose Agar medium mixed with the appropriate extract. The antioxidant activity was determined by DPPH and ABTS methods. Our data revealed the presence of various potent phytochemicals. For the reference and meat isolated strains, the inhibitory diameter zone was from 17.5 ± 0.7 mm (C. albicans) to 9.5 ± 0.7 mm (P. vulgaris). The MIC ranged from 0.312 mg/mL to 5.000 mg/mL and the MBC from 0.625 mg/mL to >20 mg/mL. The highest antifungal activity was observed with F. verticillioides and the lowest one with P. citrinum. The two extracts have an excellent reducing free radical activity. The killing effect of A. salina larvae was perceptible at 1.04 mg/mL. The purified extracts of Cola nitida's bark can be used to hold meat products and also like phytomedicine. PMID:25767723

  1. Biological activity of terpene compounds produced by biotechnological methods.

    PubMed

    Paduch, Roman; Trytek, Mariusz; Król, Sylwia K; Kud, Joanna; Frant, Maciej; Kandefer-Szerszeń, Martyna; Fiedurek, Jan

    2016-06-01

    Context Biotransformation systems are profitable tools for structural modification of bioactive natural compounds into valuable biologically active terpenoids. Objective This study determines the biological effect of (R)-(+)-limonene and (-)-α-pinene, and their oxygenated derivatives, (a) perillyl alcohol and (S)-(+)- and (R)-(-)-carvone enantiomers and (b) linalool, trans-verbenol and verbenone, respectively, on human colon tumour cells and normal colonic epithelium. Materials and methods Biotransformation procedures and in vitro cell culture tests were used in this work. Cells were incubated for 24 h with terpenes at concentrations of 5-500 μg/mL for NR, MTT, DPPH, and NO assays. IL-6 was determined by ELISA with/without 2 h pre-activation with 10 μg/mL LPS. Results trans-Verbenol and perillyl alcohol, obtained via biotransformation, produced in vitro effect against tumour cells at lower concentrations (IC50 value = 77.8 and 98.8 μg/mL, respectively) than their monoterpene precursors, (R)-(+)-limonene (IC50 value = 171.4 μg/mL) and (-)-α-pinene (IC50 value = 206.3 μg/mL). They also showed lower cytotoxicity against normal cells (IC50 > 500 and > 200 μg/mL, respectively). (S)-(+)-Carvone was 59.4% and 27.1% more toxic to tumour and normal cells, respectively, than the (R)-(-)-enantiomer. (R)-(+)-limonene derivatives decreased IL-6 production from normal cells in media with or without LPS (30.2% and 13.9%, respectively), while (-)-α-pinene derivatives induced IL-6 (verbenone had the strongest effect, 60.2% and 29.1% above control, respectively). None of the terpenes had antioxidative activity below 500 μg/mL. Discussion and conclusions Bioactivity against tumour cells decreased in the following order: alcohols > ketones > hydrocarbons. (R)-(+)-limonene, (-)-α-pinene, and their derivatives expressed diverse activity towards normal and tumour cells with noticeable enantiomeric differences. PMID:26808720

  2. Phenolic compounds characterization and biological activities of Citrus aurantium bloom.

    PubMed

    Karimi, Ehsan; Oskoueian, Ehsan; Hendra, Rudi; Oskoueian, Armin; Jaafar, Hawa Z E

    2012-01-01

    Citrus plants are known to possess beneficial biological activities for human health. In addition, ethnopharmacological application of plants is a good tool to explore their bioactivities and active compounds. This research was carried out to evaluate the phenolic and flavonoid analysis, antioxidant properties, anti inflammatory and anti cancer activity of Citrus aurantium bloom. The total phenolics and flavonoids results revealed that methanolic extract contained high total phenolics and flavonoids compared to ethanolic and boiling water extracts. The obtained total phenolics value for methanolic Citrus aurantium bloom extract was 4.55 ± 0.05 mg gallic acid equivalent (GAE)/g dry weight (DW), and for total flavonoids it was 3.83 ± 0.05 mg rutin equivalent/g DW. In addition, the RP-HPLC analyses of phenolics and flavonoids indicated the presence of gallic acid, pyrogallol, syringic acid, caffeic acid, rutin, quercetin and naringin as bioactive compounds. The antioxidant activity of Citrus aurantium bloom were examined by the 1,1-diphenyl-2-picryl-hydrazyl (DPPH) assay and the ferric reducing/antioxidant potential (FRAP). The free radical scavenging and ferric reducing power activities were higher for the methanolic extract of Citrus aurantium bloom at a concentration of 300 μg/mL, with values of 55.3% and 51.7%, respectively, as compared to the corresponding boiling water and ethanolic extracts, but the activities were lower than those of antioxidant standards such as BHT and α-tocopherol. Furthermore, the anti-inflammatory result of methanolic extract showed appreciable reduction in nitric oxide production of stimulated RAW 264.7 cells at the presence of plant extract. Apart from that, the anticancer activity of the methanolic extract was investigated in vitro against human cancer cell lines (MCF-7; MDA-MB-231), human colon adenocarcinoma (HT-29) and Chang cell as a normal human hepatocyte. The obtained result demonstrated the moderate to appreciable

  3. A Conceptual Framework for Organizing Active Learning Experiences in Biology Instruction

    ERIC Educational Resources Information Center

    Gardner, Joel; Belland, Brian R.

    2012-01-01

    Introductory biology courses form a cornerstone of undergraduate instruction. However, the predominantly used lecture approach fails to produce higher-order biology learning. Research shows that active learning strategies can increase student learning, yet few biology instructors use all identified active learning strategies. In this paper, we…

  4. Structures of bacterial kynurenine formamidase reveal a crowded binuclear zinc catalytic site primed to generate a potent nucleophile

    PubMed Central

    Díaz-Sáez, Laura; Srikannathasan, Velupillai; Zoltner, Martin; Hunter, William N.

    2014-01-01

    Tryptophan is an important precursor for chemical entities that ultimately support the biosynthesis of key metabolites. The second stage of tryptophan catabolism is catalysed by kynurenine formamidase, an enzyme that is different between eukaryotes and prokaryotes. In the present study, we characterize the catalytic properties and present the crystal structures of three bacterial kynurenine formamidases. The structures reveal a new amidase protein fold, a highly organized and distinctive binuclear Zn2+ catalytic centre in a confined, hydrophobic and relatively rigid active site. The structure of a complex with 2-aminoacetophenone delineates aspects of molecular recognition extending to the observation that the substrate itself may be conformationally restricted to assist binding in the confined space of the active site and for subsequent processing. The cations occupy a crowded environment, and, unlike most Zn2+-dependent enzymes, there is little scope to increase co-ordination number during catalysis. We propose that the presence of a bridging water/hydroxide ligand in conjunction with the placement of an active site histidine supports a distinctive amidation mechanism. PMID:24942958

  5. Teaching Systems Biology: An Active-Learning Approach

    ERIC Educational Resources Information Center

    Kumar, Anuj

    2005-01-01

    With genomics well established in modern molecular biology, recent studies have sought to further the discipline by integrating complementary methodologies into a holistic depiction of the molecular mechanisms underpinning cell function. This genomic subdiscipline, loosely termed "systems biology," presents the biology educator with both…

  6. Biological activity of piceatannol: leaving the shadow of resveratrol.

    PubMed

    Piotrowska, Hanna; Kucinska, Malgorzata; Murias, Marek

    2012-01-01

    Resveratrol (3,4',5-trans-trihydroxystilbene), a naturally occurring stilbene, is considered to have a number of beneficial effects, including anticancer, anti-aethrogenic, anti-oxidative, anti-inflammatory, anti-microbial and estrogenic activity. Piceatannol (3, 3', 4, 5'-trans-trihydroxystilbene), a naturally occurring hydroxylated analogue of resveratrol, is less studied than resveratrol but displays a wide spectrum of biological activity. Piceatannol has been found in various plants, including grapes, passion fruit, white tea, and Japanese knotweed. Besides antioxidative effects, piceatannol exhibits potential anticancer properties as suggested by its ability to suppress proliferation of a wide variety of tumor cells, including leukemia, lymphoma; cancers of the breast, prostate, colon and melanoma. The growth-inhibitory and proapoptotic effects of piceatannol are mediated through cell-cycle arrest; upregulation of Bid, Bax. Bik, Bok, Fas: P21(WAF1) down-regulation of Bcl-xL; BCL-2, clAP, activation of caspases (-3, -7,- 8, -9), loss of mitochondrial potential, and release of cytochrome c. Piceatannol has been shown to suppress the activation of some transcription factors, including NF-kappaB, which plays a central role as a transcriptional regulator in response to cellular stress caused by free radicals, ultraviolet irradiation, cytokines, or microbial antigens. Piceatannol also inhibits JAK-1, which is a key member of the STAT pathway that is crucial in controlling cellular activities in response to extracellular cytokines and is a COX-2-inducible enzyme involved in inflammation and carcinogenesis. Although piceatannol has been shown to induce apoptosis in cancer cells, there are examples of its anti-apoptotic pro-proliferative activity. Piceatannol inhibits Syk kinase, which plays a crucial role in the coordination of immune recognition receptors and orchestrates multiple downstream signaling pathways in various hematopoietic cells. Piceatannol also binds

  7. Prescribed Active Learning Increases Performance in Introductory Biology

    PubMed Central

    O'Connor, Eileen; Parks, John W.; Cunningham, Matthew; Hurley, David; Haak, David; Dirks, Clarissa; Wenderoth, Mary Pat

    2007-01-01

    We tested five course designs that varied in the structure of daily and weekly active-learning exercises in an attempt to lower the traditionally high failure rate in a gateway course for biology majors. Students were given daily multiple-choice questions and answered with electronic response devices (clickers) or cards. Card responses were ungraded; clicker responses were graded for right/wrong answers or participation. Weekly practice exams were done as an individual or as part of a study group. Compared with previous versions of the same course taught by the same instructor, students in the new course designs performed better: There were significantly lower failure rates, higher total exam points, and higher scores on an identical midterm. Attendance was higher in the clicker versus cards section; attendance and course grade were positively correlated. Students did better on clicker questions if they were graded for right/wrong answers versus participation, although this improvement did not translate into increased scores on exams. In this course, achievement increases when students get regular practice via prescribed (graded) active-learning exercises. PMID:17548875

  8. Pomegranate fruit as a rich source of biologically active compounds.

    PubMed

    Sreekumar, Sreeja; Sithul, Hima; Muraleedharan, Parvathy; Azeez, Juberiya Mohammed; Sreeharshan, Sreeja

    2014-01-01

    Pomegranate is a widely used plant having medicinal properties. In this review, we have mainly focused on the already published data from our laboratory pertaining to the effect of methanol extract of pericarp of pomegranate (PME) and have compared it with other relevant literatures on Punica. Earlier, we had shown its antiproliferative effect using human breast (MCF-7, MDA MB-231), and endometrial (HEC-1A), cervical (SiHa, HeLa), and ovarian (SKOV3) cancer cell lines, and normal breast fibroblasts (MCF-10A) at concentration of 20-320 μg/mL. The expressions of selected estrogen responsive genes (PR, pS2, and C-Myc) were downregulated by PME. Unlike estradiol, PME did not increase the uterine weight and proliferation in bilaterally ovariectomized Swiss-Albino mice models and its cardioprotective effects were comparable to that of 17 β -estradiol. We had further assessed the protective role of PME on skeletal system, using MC3T3-E1 cells. The results indicated that PME (80 μg/mL) significantly increased ALP (Alkaline Phosphatase) activity, supporting its suggested role in modulating osteoblastic cell differentiation. The antiosteoporotic potential of PME was also evaluated in ovariectomized (OVX) rodent model. The results from our studies and from various other studies support the fact that pomegranate fruit is indeed a source of biologically active compounds. PMID:24818149

  9. Chemistry, biogenesis, and biological activities of Cinnamomum zeylanicum.

    PubMed

    Jayaprakasha, G K; Rao, L Jagan Mohan

    2011-07-01

    The genus Cinnamomum comprises of several hundreds of species, which are distributed in Asia and Australia. Cinnamomum zeylanicum, the source of cinnamon bark and leaf oils, is an indigenous tree of Sri Lanka, although most oil now comes from cultivated areas. C. zeylanicum is an important spice and aromatic crop having wide applications in flavoring, perfumery, beverages, and medicines. Volatile oils from different parts of cinnamon such as leaves, bark, fruits, root bark, flowers, and buds have been isolated by hydro distillation/steam distillation and supercritical fluid extraction. The chemical compositions of the volatile oils have been identified by GC and GC-MS. More than 80 compounds were identified from different parts of cinnamon. The leaf oil has a major component called eugenol. Cinnamaldehyde and camphor have been reported to be the major components of volatile oils from stem bark and root bark, respectively. Trans-cinnamyl acetate was found to be the major compound in fruits, flowers, and fruit stalks. These volatile oils were found to exhibit antioxidant, antimicrobial, and antidiabetic activities. C. zeylanicum bark and fruits were found to contain proanthocyandins with doubly linked bis-flavan-3-ol units in the molecule. The present review provides a coherent presentation of scattered literature on the chemistry, biogenesis, and biological activities of cinnamon. PMID:21929331

  10. Immunoreactive and biologically active somatostatin in human and sheep milk.

    PubMed

    Werner, H; Amarant, T; Millar, R P; Fridkin, M; Koch, Y

    1985-04-15

    The presence of immunoreactive and biologically active somatostatin in sheep and human milk has been demonstrated. Milk somatostatin exhibits similar chromatographic behavior to that of synthetic somatostatin-14 on both reversed-phase C18 and cation-exchange high-performance liquid chromatography columns. Milk, in contrast to plasma, contains only somatostatin-14-like material. Milk somatostatin was capable of inhibiting the basal and the prostaglandin-induced release of growth hormone from anterior pituitary cell cultures in a pattern similar to synthetic somatostatin-14. The concentrations of the peptide, as determined by radioimmunoassay, were found to be 113 pg/ml in human milk and 150 +/- 4.8 pg/ml (mean +/- range) in sheep milk. These values are severalfold higher than the corresponding concentration of the peptide in the plasma of these species. These findings are analogous to our previous observations concerning two other hypothalamic hormones, luliberin and thyroliberin [Baram, T., Koch, Y., Hazum, E. and Fridkin, M. (1977) Science (Wash. DC) 198, 300-302]. The high concentration of somatostatin and other neuropeptides in milk implies either an active concentrating mechanism in the mammary gland or an additional extrahypothalamic source for the synthesis and release of these peptides. PMID:2859195

  11. Steroid receptor RNA activator: Biologic function and role in disease.

    PubMed

    Liu, Chan; Wu, Hong-Tao; Zhu, Neng; Shi, Ya-Ning; Liu, Zheng; Ao, Bao-Xue; Liao, Duan-Fang; Zheng, Xi-Long; Qin, Li

    2016-08-01

    Steroid receptor RNA activator (SRA) is a type of long noncoding RNA (lncRNA) which coordinates the functions of various transcription factors, enhances steroid receptor-dependent gene expression, and also serves as a distinct scaffold. The novel, profound and expanded roles of SRA are emerging in critical aspects of coactivation of nuclear receptors (NRs). As a nuclear receptor coactivator, SRA can coactivate androgen receptor (AR), estrogen receptor α (ERα), ERβ, progesterone receptor (PR), glucocorticoid receptor (GR), thyroid hormone receptor and retinoic acid receptor (RAR). Although SRA is one of the least well-understood molecules, increasing studies have revealed that SRA plays a key role in both biological processes, such as myogenesis and steroidogenesis, and pathological changes, including obesity, cardiomyopathy, and tumorigenesis. Furthermore, the SRA-related signaling pathways, such as the mitogen-activated protein kinase (p38 MAPK), Notch and tumor necrosis factor α (TNFα) pathways, play critical roles in the pathogenesis of estrogen-dependent breast cancers. In addition, the most recent data demonstrates that SRA expression may serve as a new prognostic marker in patients with ER-positive breast cancer. Thus, elucidating the molecular mechanisms underlying SRA-mediated functions is important to develop proper novel strategies to target SRA in the diagnosis and treatment of human diseases. PMID:27282881

  12. On Some Passive and Active Motion in Biology

    NASA Astrophysics Data System (ADS)

    Misbah, Chaouqi

    This contribution focuses on two main questions inspired by biology: (i) passive motion under flow, like advection of red blood cells in the circulatory system, and (ii) active motion generated by actin polymerization, as encountered in cells of the immune system and some micro-organisms (e.g. some bacteria and viruses). The first part is dedicated to the dynamics and rheology of vesicles (a simple model for red blood cells) under flow. Some results obtained on red blood cells are also presented and compared to vesicles. Vesicles and red blood cells under flow exhibit several interesting dynamics: tank-treading, tumbling, vacillating-breathing, and so on. These dynamics have a direct impact on rheology, as will be discussed both from the theoretical and experimental point of views. The second part addresses active motion. Some Bacteria (like Listeria) are known to transfect cells thanks to the polymerization on their surface of an actin gel. Monomeric actin proteins are recruited from the transfected cell when the bacteria gets in contact with the cell surface. It has been found that the bacteria propulsion into the cell occurs in the absence of molecular motors. Biomimetic experiments on beads and droplets have revealed that motion is a consequence of a spontaneous symmetry breaking that is accompanied with force generation. A simple basic model taking into account growth of actin and elasticity is sufficient to capture the essence of symmetry breaking and force generation, as will be presented in this contribution.

  13. Hen's egg as a source of valuable biologically active substances.

    PubMed

    Zdrojewicz, Zygmunt; Herman, Marta; Starostecka, Ewa

    2016-01-01

    The aim of this article is to show current knowledge concerning valuable substances biologically active present in hen eggs and underline important nutritive role of hen eggs. Hen egg is a good source of nutrients such as proteins, vitamins (A, B2, B6, B12, D, E, K), minerals and lipids. The significant part of lipids is a group of unsaturated phospholipids, which are components of cell membranes, act protectively on the cardiovascular system and contribute to a decrease of cholesterol level and blood pressure. Therefore, the consumption of unsaturated phospholipids is recommended especially in patients suffering from diseases of the cardiovascular system. Another important substance is egg cystatin, which has a wide spectrum of biological functions, for example the ability to stimulate cell growth, inhibit inflammatory processes and has antibacterial and antiviral properties. Other substance presented in the egg white which helps fight bacteria is lysozyme. It is used in medicine as an aid in antibiotic therapy and analgesic in the course of infection, as well as in tumor malignancies. Among the components contained in the egg yolk there is also immunoglobulin Y which due to its therapeutic importance deserves special attention. Its use offers the possibility of replacing chemotherapeutic agents in the treatment of bacterial infections of digestive system, as well as an opportunity for the development of medicine associated with passive immunization of patients. The egg is a rich source of retinol which gradual depletion in the organism causes many eye pathologies. A very important and useful part of the egg, used in medicine is a shell and its membranes, due to the high collagen content relevant in the treatment of connective tissue diseases. PMID:27383572

  14. Syntheses and biological activities of 13-substituted avermectin aglycons.

    PubMed

    Mrozik, H; Linn, B O; Eskola, P; Lusi, A; Matzuk, A; Preiser, F A; Ostlind, D A; Schaeffer, J M; Fisher, M H

    1989-02-01

    The reactions of sulfonate esters of the allylic/homoallylic 13-alcohol of 5-O-(tert-butyldimethylsilyl)-22,23-dihydroavermectin B1a aglycon (1a) were investigated. Nucleophilic substitution gave 13 beta-chloro and 13 beta-iodo derivatives, while solvolytic reaction conditions yielded 13 alpha-methoxy, 13 alpha-fluoro, and 13 alpha-chloro products. A mixture of 13 alpha- and 13 beta-fluorides was obtained upon reaction with DAST. The 13 beta-iodide gave, upon elimination with lutidine, the 8(9),10(11),12(13),14(15)-tetraene. The 13 beta-alcohol and the rearranged 15-ol 13(14)-ene and 15-amino 13(14)-ene derivatives were obtained by substitution via the allylic carbonium ion. MEM ethers 11 and 12 of the two epimeric 13-ols were prepared by alkylation with MEM chloride. In contrast, methylation of 1a with MeI and Ag2O in CH2Cl2 occurred exclusively at the tertiary 7-hydroxy group and not at the secondary 13 alpha-ol. Oxidation of the allylic alcohol 1a proceeded under Swern conditions but not with MnO2 to the 13-oxo aglycon, which was reduced by NaBH4 exclusively to the natural 13 alpha-ol, while reductive amination with NaCNBH3-NH4OAc gave the 13 alpha-amine. The methoxime derivative was obtained in the form of the two geometric isomers. Anthelmintic activities against the sheep nematode Trichostrongylus colubriformis, miticidal activities against the two-spotted spider mite (Tetranychus urticae), and insecticidal activities against the southern armyworm (Spodoptera eridania) as well as the binding constants to a free living nematode (Caenorhabditis elegans) derived receptor assay were obtained and compared to avermectin B1a, 22,23-dihydroavermectin B1a, and the 13-deoxy-22,23-dihydroavermectin B1 aglycon related to the milbemycins. None of the newly prepared derivatives exceeded the potency of the three reference compounds. Lipophilic 13-substituents such as halogen, alkoxy, and methoxime retained high biological activities in all assays, while the more polar

  15. Important biological activities induced by Thalassophryne maculosa fish venom.

    PubMed

    Sosa-Rosales, Josefina Ines; Piran-Soares, Ana Amélia; Farsky, Sandra H P; Takehara, Harumi Ando; Lima, Carla; Lopes-Ferreira, Mônica

    2005-02-01

    The accidents caused by Thalassophryne maculosa fish venoms are frequent and represent a public health problem in some regions of Venezuela. Most accidents occur in the fishing communities and tourists. The clinical picture is characterized by severe pain, dizziness, fever, edema, and necrosis. Due to the lack of efficient therapy it may take weeks, or even months for complete recovery of the victims. The investigations presented here were undertaken to assess the eletrophoretical profile and principal biological properties of the T. maculosa venom. Venom obtained from fresh captured specimens of this fish was tested in vitro or in animal models for a better characterization of its toxic activities. In contrast to other fish venoms, T. maculosa venom showed relative low LD50. The injection of venom in the footpad of mice reproduced a local inflammatory lesion similar to that described in humans. Significant increase of the nociceptive and edematogenic responses was observed followed within 48 h by necrosis. Pronounced alterations on microvascular hemodynamics were visualized after venom application. These alterations were represented by fibrin depots and thrombus formation followed by complete venular stasis and transient arteriolar contraction. T. maculosa venom is devoid of phospholipase A2 activity, but the venom showed proteolytic and myotoxic activities. SDS-Page analysis of the crude venom showed important bands: one band located above 97 M(w), one band between 68 and 97 M(w), one major band between 29 and 43 M(w) and the last one located below 18.4 M(w) Then, the results presented here support that T. maculosa venom present a mixture of bioactive toxins involved in a local inflammatory lesion. PMID:15626364

  16. Actinobacteria from Arid and Desert Habitats: Diversity and Biological Activity

    PubMed Central

    Mohammadipanah, Fatemeh; Wink, Joachim

    2016-01-01

    The lack of new antibiotics in the pharmaceutical pipeline guides more and more researchers to leave the classical isolation procedures and to look in special niches and ecosystems. Bioprospecting of extremophilic Actinobacteria through mining untapped strains and avoiding resiolation of known biomolecules is among the most promising strategies for this purpose. With this approach, members of acidtolerant, alkalitolerant, psychrotolerant, thermotolerant, halotolerant and xerotolerant Actinobacteria have been obtained from respective habitats. Among these, little survey exists on the diversity of Actinobacteria in arid areas, which are often adapted to relatively high temperatures, salt concentrations, and radiation. Therefore, arid and desert habitats are special ecosystems which can be recruited for the isolation of uncommon Actinobacteria with new metabolic capability. At the time of this writing, members of Streptomyces, Micromonospora, Saccharothrix, Streptosporangium, Cellulomonas, Amycolatopsis, Geodermatophilus, Lechevalieria, Nocardia, and Actinomadura are reported from arid habitats. However, metagenomic data present dominant members of the communities in desiccating condition of areas with limited water availability that are not yet isolated. Furthermore, significant diverse types of polyketide synthase (PKS) and non-ribosomal peptide synthetase (NRPS) genes are detected in xerophilic and xerotolerant Actinobacteria and some bioactive compounds are reported from them. Rather than pharmaceutically active metabolites, molecules with protection activity against drying such as Ectoin and Hydroxyectoin with potential application in industry and agriculture have also been identified from xerophilic Actinobacteria. In addition, numerous biologically active small molecules are expected to be discovered from arid adapted Actinobacteria in the future. In the current survey, the diversity and biotechnological potential of Actinobacteria obtained from arid ecosystems

  17. [Biologically active substances of black currant of new varieties].

    PubMed

    Miasishcheva, N V; Artemova, E N

    2013-01-01

    The assortment of black currant actively replenishes and is constantly updated as a result of successful work of domestic and foreign selectors. New grades of black currant are characterized by the raised content of biologically active substances, including vitamin C, P-active agents, pectin and are of special interest for studying. Fresh berries of seven grades (Azhurnaya, Arapka, Iskushenie, Kreolka, Ladushka, Orel serenade, Ocharovanie) of black currant which were selected by the All-Russian research institute of selection of fruit crops and are perspective for cultivation in the Central Chernozem Region of Russia were chosen as objects for research. The nutritional value of fresh berries was found to vary. Average content of soluble solids was 14.1%, while those below the average were observed in Kreolka (12.1%). The maximum amount of sugars characterized Ladushka grade (11.05%), minimum--Kreolka (9.00%). It has been found that most varieties have fairly high acidity. It is worth noting grade Ladushka, which had the highest sugar-acid index (4.39), with the lowest acidity (2.51%). The highest content of ascorbic acid was found in varieties Orel Serenade--183.7 mg/100 g, the smallest--Ocharovanie--110 mg/100 g, grade Azhurnaya, Kreolka, Ladushka exceeded this indicator average value (144.9 mg/100 g). In terms of the amount of P-active substances stood grades having values above the average (722.2 mg/100 g): Azhurnaya (789.8 mg/100 g), Kreolka (864.5 mg/100 g), Oryol serenade (765.6 mg/100 g). The average content of pectin in the studied berries of black currant was 7.92%, with a minimum of 6.30% was observed in grades Azhurnaya, maximum 9.90%--the kind Oryol serenade. High values of this index were characterized by grade Ladushka, Ocharovanie. Azhurnaya varieties, Creole, Orel serenade had high levels of ascorbic acid and P-active substances. Sort Ladushka marked as a dessert due to the largest sugar-acid ratio. Ladushka, Orel Serenade, Ocharovanie have the

  18. Biologic activity of antigen receptors artificially incorporated onto B lymphocytes.

    PubMed

    Peacock, J S; Londo, T R; Roess, D A; Barisas, B G

    1986-09-15

    We describe a method for incorporating monoclonal antibody molecules onto viable murine lymphocytes and summarize the biologic activity of these artificial receptors on B cells. Mouse spleen cells incubated overnight with palmitate conjugates of a monoclonal anti-DNP IgA (protein 315) in the presence of deoxycholic acid incorporate about 50,000 antibody molecules per cell. When concentrations of deoxycholate and palmitoyl-protein 315 are carefully controlled, this labeling procedure does not affect the viability or the normal functions of the receptor-decorated cells. The incorporated antibody specifically binds DNP-antigens, although it appears to be unable to communicate directly with internal cellular components. Yet when these receptor-decorated, unprimed cells are challenged with any one of several DNP-antigens, up to 42,000 per 10(6) B cells differentiate into Ig-secreting cells. This response is about 23-fold greater than that induced in normal cell cultures and is of the same magnitude as that induced by the polyclonal B cell activator LPS. This, in addition to the observation that only about 3.6% of receptor-decorated B cells responding to DNP-conjugated polymerized flagellin (DNP-POL) produce hapten-specific antibody, demonstrates that these antigens cause polyclonal B cell differentiation. Normal spleen cells in the presence of DNP-POL and irradiated spleen cells bearing the artificial receptors do not exhibit the polyclonal antibody response. Also, the response of receptor-decorated B cell is blocked by high but nontoxic concentrations of the nonimmunogenic hapten DNP-lysine. These observations demonstrate that the polyclonal B cell response in this system requires the binding of antigen to artificial receptors on functionally viable cells. The polyclonal B cell response to a thymus-dependent antigen DNP-conjugated bovine gamma-globulin (DNP-BGG) requires the presence of the carrier-primed T cells. On the other hand, T cell depletion by anti-Thy-1

  19. STUDIES OF RELATIONSHIPS BETWEEN MOLECULAR STRUCTURE AND BIOLOGICAL ACTIVITY BY PATTERN RECOGNITION METHODS

    EPA Science Inventory

    The attempt to rationalize the connections between the molecular structures of organic compounds and their biological activities comprises the field of structure-activity relations (SAR) studies. Correlations between structure and activity are important for the understanding and ...

  20. Biological activity of harpin produced by Pantoea stewartii subsp. stewartii.

    PubMed

    Ahmad, M; Majerczak, D R; Pike, S; Hoyos, M E; Novacky, A; Coplin, D L

    2001-10-01

    Pantoea stewartii subsp. stewartii causes Stewart's wilt of sweet corn. A hypersensitive response and pathogenicity (Hrp) secretion system is needed to produce water-soaking and wilting symptoms in corn and to cause a hypersensitive response (HR) in tobacco. Sequencing of the hrp cluster revealed a putative harpin gene, hrpN. The product of this gene was overexpressed in Escherichia coli and shown to elicit the HR in tobacco and systemic resistance in radishes. The protein was designated HrpN(Pnss). Like other harpins, it was heat stable and protease sensitive, although it was three- to fourfold less active biologically than Erwinia amylovora harpin. We used antibodies to purified HrpN(Pnss) to verify that hrpN mutants could not produce harpin. This protein was secreted into the culture supernatant and was produced by strains of P. stewartii subsp. indologenes. In order to determine the importance of HrpN(Pnss) in pathogenesis on sweet corn, three hrpN::Tn5 mutants were compared with the wild-type strain with 50% effective dose, disease severity, response time, and growth rate in planta as parameters. In all tests, HrpN(Pnss) was not required for infection, growth, or virulence in corn or endophytic growth in related grasses. PMID:11605962

  1. Role of Calcium Signaling in B Cell Activation and Biology.

    PubMed

    Baba, Yoshihiro; Kurosaki, Tomohiro

    2016-01-01

    Increase in intracellular levels of calcium ions (Ca2+) is one of the key triggering signals for the development of B cell response to the antigen. The diverse Ca2+ signals finely controlled by multiple factors participate in the regulation of gene expression, B cell development, and effector functions. B cell receptor (BCR)-initiated Ca2+ mobilization is sourced from two pathways: one is the release of Ca2+ from the intracellular stores, endoplasmic reticulum (ER), and other is the prolonged influx of extracellular Ca2+ induced by depleting the stores via store-operated calcium entry (SOCE) and calcium release-activated calcium (CRAC) channels. The identification of stromal interaction molecule 1(STIM1), the ER Ca2+ sensor, and Orai1, a key subunit of the CRAC channel pore, has now provided the tools to understand the mode of Ca2+ influx regulation and physiological relevance. Herein, we discuss our current understanding of the molecular mechanisms underlying BCR-triggered Ca2+ signaling as well as its contribution to the B cell biological processes and diseases. PMID:26369772

  2. Biological aerosol detection with combined passive-active infrared measurements

    NASA Astrophysics Data System (ADS)

    Ifarraguerri, Agustin I.; Vanderbeek, Richard G.; Ben-David, Avishai

    2004-12-01

    A data collection experiment was performed in November of 2003 to measure aerosol signatures using multiple sensors, all operating in the long-wave infrared. The purpose of this data collection experiment was to determine whether combining passive hyperspectral and LIDAR measurements can substantially improve biological aerosol detection performance. Controlled releases of dry aerosols, including road dust, egg albumin and two strains of Bacillus Subtilis var. Niger (BG) spores were performed using the ECBC/ARTEMIS open-path aerosol test chamber located in the Edgewood Area of Aberdeen Proving Grounds, MD. The chamber provides a ~ 20' path without optical windows. Ground truth devices included 3 aerodynamic particle sizers, an optical particle size spectrometer, 6 nephelometers and a high-volume particle sampler. Two sensors were used to make measurements during the test: the AIRIS long-wave infrared imaging spectrometer and the FAL CO2 LIDAR. The AIRIS and FAL data sets were analyzed for detection performance relative to the ground truth. In this paper we present experimental results from the individual sensors as well as results from passive-active sensor fusion. The sensor performance is presented in the form of receiver operating characteristic curves.

  3. Chelating ability and biological activity of hesperetin Schiff base.

    PubMed

    Lodyga-Chruscinska, Elzbieta; Symonowicz, Marzena; Sykula, Anna; Bujacz, Anna; Garribba, Eugenio; Rowinska-Zyrek, Magdalena; Oldziej, Stanislaw; Klewicka, Elzbieta; Janicka, Magdalena; Krolewska, Karolina; Cieslak, Marcin; Brodowska, Katarzyna; Chruscinski, Longin

    2015-02-01

    Hydrazone hesperetin Schiff base (HHSB) - N-[(±)-[5,7-dihydroxy-2-(3-hydroxy-4-methoxy-phenyl)chroman-4-ylidene]amino]benzamide has been synthesized and its crystal structure was determined. This compound was used for the formation of Cu(II) complexes in solid state and in solution which were characterized using different spectroscopic methods. The analyses of potentiometric titration curves revealed that monomeric and dimeric complexes of Cu(II) are formed above pH7. The ESI-MS (electrospray ionization-mass spectrometry) spectra confirmed their formation. The EPR and UV-visible spectra evidenced the involvement of oxygen and nitrogen atoms in Cu(II) coordination. Hydrazone hesperetin Schiff base can show keto-enol tautomerism and coordinate Cu(II) in the keto (O(-), N, Oket) and in the enolate form (O(-), N, O(-)enol). The semi-empirical molecular orbital method PM6 and DFT (density functional theory) calculations have revealed that the more stable form of the dimeric complex is that one in which the ligand is present in the enol form. The CuHHSB complex has shown high efficiency in the cleavage of plasmid DNA in aqueous solution, indicating its potential as chemical nuclease. Studies on DNA interactions, antimicrobial and cytotoxic activities have been undertaken to gain more information on the biological significance of HHSB and copper(II)-HHSB chelate species. PMID:25486205

  4. TEAK: topology enrichment analysis framework for detecting activated biological subpathways.

    PubMed

    Judeh, Thair; Johnson, Cole; Kumar, Anuj; Zhu, Dongxiao

    2013-02-01

    To mine gene expression data sets effectively, analysis frameworks need to incorporate methods that identify intergenic relationships within enriched biologically relevant subpathways. For this purpose, we developed the Topology Enrichment Analysis frameworK (TEAK). TEAK employs a novel in-house algorithm and a tailor-made Clique Percolation Method to extract linear and nonlinear KEGG subpathways, respectively. TEAK scores subpathways using the Bayesian Information Criterion for context specific data and the Kullback-Leibler divergence for case-control data. In this article, we utilized TEAK with experimental studies to analyze microarray data sets profiling stress responses in the model eukaryote Saccharomyces cerevisiae. Using a public microarray data set, we identified via TEAK linear sphingolipid metabolic subpathways activated during the yeast response to nitrogen stress, and phenotypic analyses of the corresponding deletion strains indicated previously unreported fitness defects for the dpl1Δ and lag1Δ mutants under conditions of nitrogen limitation. In addition, we studied the yeast filamentous response to nitrogen stress by profiling changes in transcript levels upon deletion of two key filamentous growth transcription factors, FLO8 and MSS11. Via TEAK we identified a nonlinear glycerophospholipid metabolism subpathway involving the SLC1 gene, which we found via mutational analysis to be required for yeast filamentous growth. PMID:23268448

  5. Sustainable production of biologically active molecules of marine based origin.

    PubMed

    Murray, Patrick M; Moane, Siobhan; Collins, Catherine; Beletskaya, Tanya; Thomas, Olivier P; Duarte, Alysson W F; Nobre, Fernando S; Owoyemi, Ifeloju O; Pagnocca, Fernando C; Sette, L D; McHugh, Edward; Causse, Eric; Pérez-López, Paula; Feijoo, Gumersindo; Moreira, Ma T; Rubiolo, Juan; Leirós, Marta; Botana, Luis M; Pinteus, Susete; Alves, Celso; Horta, André; Pedrosa, Rui; Jeffryes, Clayton; Agathos, Spiros N; Allewaert, Celine; Verween, Annick; Vyverman, Wim; Laptev, Ivan; Sineoky, Sergei; Bisio, Angela; Manconi, Renata; Ledda, Fabio; Marchi, Mario; Pronzato, Roberto; Walsh, Daniel J

    2013-09-25

    The marine environment offers both economic and scientific potential which are relatively untapped from a biotechnological point of view. These environments whilst harsh are ironically fragile and dependent on a harmonious life form balance. Exploitation of natural resources by exhaustive wild harvesting has obvious negative environmental consequences. From a European industry perspective marine organisms are a largely underutilised resource. This is not due to lack of interest but due to a lack of choice the industry faces for cost competitive, sustainable and environmentally conscientious product alternatives. Knowledge of the biotechnological potential of marine organisms together with the development of sustainable systems for their cultivation, processing and utilisation are essential. In 2010, the European Commission recognised this need and funded a collaborative RTD/SME project under the Framework 7-Knowledge Based Bio-Economy (KBBE) Theme 2 Programme 'Sustainable culture of marine microorganisms, algae and/or invertebrates for high value added products'. The scope of that project entitled 'Sustainable Production of Biologically Active Molecules of Marine Based Origin' (BAMMBO) is outlined. Although the Union is a global leader in many technologies, it faces increasing competition from traditional rivals and emerging economies alike and must therefore improve its innovation performance. For this reason innovation is placed at the heart of a European Horizon 2020 Strategy wherein the challenge is to connect economic performance to eco performance. This article provides a synopsis of the research activities of the BAMMBO project as they fit within the wider scope of sustainable environmentally conscientious marine resource exploitation for high-value biomolecules. PMID:23563183

  6. Intramolecular hydrogen bond in biologically active o-carbonyl hydroquinones.

    PubMed

    Martínez-Cifuentes, Maximiliano; Weiss-López, Boris E; Santos, Leonardo S; Araya-Maturana, Ramiro

    2014-01-01

    Intramolecular hydrogen bonds (IHBs) play a central role in the molecular structure, chemical reactivity and interactions of biologically active molecules. Here, we study the IHBs of seven related o-carbonyl hydroquinones and one structurally-related aromatic lactone, some of which have shown anticancer and antioxidant activity. Experimental NMR data were correlated with theoretical calculations at the DFT and ab initio levels. Natural bond orbital (NBO) and molecular electrostatic potential (MEP) calculations were used to study the electronic characteristics of these IHB. As expected, our results show that NBO calculations are better than MEP to describe the strength of the IHBs. NBO energies (∆Eij(2)) show that the main contributions to energy stabilization correspond to LP-->σ* interactions for IHBs, O1…O2-H2 and the delocalization LP-->π* for O2-C2=Cα(β). For the O1…O2-H2 interaction, the values of ∆Eij(2) can be attributed to the difference in the overlap ability between orbitals i and j (Fij), instead of the energy difference between them. The large energy for the LP O2-->π* C2=Cα(β) interaction in the compounds 9-Hydroxy-5-oxo-4,8, 8-trimethyl-l,9(8H)-anthracenecarbolactone (VIII) and 9,10-dihydroxy-4,4-dimethylanthracen-1(4H)-one (VII) (55.49 and 60.70 kcal/mol, respectively) when compared with the remaining molecules (all less than 50 kcal/mol), suggests that the IHBs in VIII and VII are strongly resonance assisted. PMID:24995921

  7. Investigating the Use of Inquiry & Web-Based Activities with Inclusive Biology Learners

    ERIC Educational Resources Information Center

    Bodzin, Alec M.; Waller, Patricia L.; Edwards, Lana; Darlene Kale, Santoro

    2007-01-01

    A Web-integrated biology program is used to explore how to best assist inclusive high school students to learn biology with inquiry-based activities. Classroom adaptations and instructional strategies teachers may use to assist in promoting biology learning with inclusive learners are discussed.

  8. Activities for Students: Biology as a Source for Algebra Equations--The Heart

    ERIC Educational Resources Information Center

    Horak, Virginia M.

    2005-01-01

    The high school course that integrated first year algebra with an introductory environmental biology/anatomy and physiology course, in order to solve algebra problems is discussed. Lessons and activities for the course were taken by identifying the areas where mathematics and biology content intervenes may help students understand biology concepts…

  9. Structure of a Novel Phosphotriesterase from Sphingobium sp. TCM1: A Familiar Binuclear Metal Center Embedded in a Seven-Bladed β-Propeller Protein Fold.

    PubMed

    Mabanglo, Mark F; Xiang, Dao Feng; Bigley, Andrew N; Raushel, Frank M

    2016-07-19

    A novel phosphotriesterase was recently discovered and purified from Sphingobium sp. TCM1 (Sb-PTE) and shown to catalyze the hydrolysis of a broad spectrum of organophosphate esters with a catalytic efficiency that exceeds 10(6) M(-1) s(-1) for the hydrolysis of triphenyl phosphate. The enzyme was crystallized and the three-dimensional structure determined to a resolution of 2.1 Å using single-wavelength anomalous diffraction (Protein Data Bank entry 5HRM ). The enzyme adopts a seven-bladed β-propeller protein fold, and three disulfide bonds were identified between Cys-146 and Cys-242, Cys-411 and Cys-443, and Cys-542 and Cys-559. The active site of Sb-PTE contains a binuclear manganese center that is nearly identical to that of the structurally unrelated phosphotriesterase from Pseudomonas diminuta (Pd-PTE). The two metal ions in the active site are bridged to one another by Glu-201 and a water molecule. The α-metal ion is further coordinated to the protein by interactions with His-389, His-475, and Glu-407, whereas the β-metal ion is further liganded to His-317 and His-258. Computational docking of mimics of the proposed pentavalent reaction intermediates for the hydrolysis of organophosphates was used to provide a model for the binding of chiral substrates in the active site of Sb-PTE. The most striking difference in the catalytic properties of Sb-PTE, relative to those of Pd-PTE, is the enhanced rate of hydrolysis of organophosphate esters with substantially weaker leaving groups. The structural basis for this difference in the catalytic properties between Sb-PTE and Pd-PTE, despite the nearly identical binuclear metal centers for the activation of the substrate and nucleophilic water molecule, is at present unclear. PMID:27353520

  10. Recombinant human betacellulin. Molecular structure, biological activities, and receptor interaction.

    PubMed

    Watanabe, T; Shintani, A; Nakata, M; Shing, Y; Folkman, J; Igarashi, K; Sasada, R

    1994-04-01

    Soluble forms of human betacellulin (BTC) were purified to homogeneity from the conditioned medium of mouse A9 cells transfected with the BTC precursor cDNA. Three types of soluble BTC, designated BTC-1a, BTC-1b and BTC-2, were resolved by cation-exchange and size-exclusion column chromatography. Physicochemical analysis has revealed that BTC-1a represents the glycosylated, intact molecule composed of 80 amino acid residues (Asp32 to Tyr111 of the precursor molecule). BTC-1b appears to be a truncated molecule lacking 12 amino acid residues from the amino terminus of BTC-1a. BTC-2 was found to be a 50-amino acid molecule (Arg62 to Tyr111) that corresponds to the epidermal growth factor (EGF) structural unit. The biological activities of these BTC molecules were essentially identical as judged by their mitogenicity on Balb/c 3T3 fibroblasts. BTC and EGF were equipotent in stimulating Balb/c 3T3 cell proliferation and rat mesangial cell Ca2+ mobilization as well as in inhibiting the growth of human epidermoid carcinoma A431 cells. BTC and EGF antagonized each other with similar dose dependence for binding to A431 cells, indicating that these factors bind the same receptor molecules with equivalent avidity. The Kd value of EGF receptor (EGFR) and BTC is 0.5 nM as determined on Balb/c 3T3 cells. In addition, human mammary carcinoma MDA-MB-453 cells, which express multiple members of the EGFR family, were found to possess 2.7 x 10(3) BTC binding sites/cell, and the binding was readily quenched by EGF. These results suggest that the primary receptor for BTC is EGFR. PMID:8144591

  11. Synthesis, crystal structures, and magnetism of the binuclear radical complex [N-methylpyridinium]2[Ni(tdas)2]2

    NASA Astrophysics Data System (ADS)

    Chen, Xue-Xue; Qiao, Fang; Wang, Chi-Feng; Chi, Yan-Hui; Cottrill, Ethan; Pan, Ning; Shi, Jing-Min; Zhu-Ge, Wei-Wei; Fu, Yong-Xin; Xu, Jun; Qian, Xiao-Ping

    2016-03-01

    The novel binuclear radical complex [N-methylpyridinium]2[Ni(tdas)2]2 (tdas = 1,2,5-thiadiazole-3,4-dithiolate) has been prepared and its crystal structures determined by X-ray crystallography at three different temperatures in order to investigate the changes in coordination structure and magnetic properties with temperature. In the binuclear radical complex the two nickel ions assume a distorted pyramidal geometry and are bridged by two S atoms of different tdas anionic ligands. At room temperature, the ESR spectrum of the binuclear radical complex in polycrystalline powder and the theoretical calculations reveal a very strong antiferromagnetic interaction, leading to diamagnetic crystals. In contrast, a peak with g = 2.05 appears in the ESR spectrum of the title complex in acetonitrile solution, which indicates that a fraction of the binuclear radical complexes dissociate. The theoretical calculations also reveal that as temperature increases the antiferromagnetic coupling strength gradually decreases, yet at 150 °C the antiferromagnetic coupling strength remains as strong as 2J = -734.26 cm-1. The strong antiferromagnetic coupling strengths should be attributed to the large spin densities on the nickel atoms and the relevant bridging sulfur atoms. This study is the first to report the correlations between the structure, magnetism, and temperature of a binuclear radical nickel complex with tdas as ligand and this study is also the first report the magnetic coupling strength of radical binuclear nickel complex with tdas as bridging ligand and with N-methylpyridinium as counter cation.

  12. Cyclopenta[c]phenanthrenes--chemistry and biological activity.

    PubMed

    Brzuzan, Paweł; Góra, Maciej; Luczyński, Michał K; Woźny, Maciej

    2013-06-25

    Despite cyclopenta-fused polycyclic aromatic hydrocarbons (CP-PAHs) having been detected in the environment, the ability of these compounds to induce cellular and tissue responses remains poorly characterized. In this review, we look at the chemistry and biological activity of the cyclopenta[c]phenanthrenes (CP[c]Phs) as potential chemicals of concern in the process of risk assessment. The first part of the review deals with the environmental occurrence and chemistry of CP-PAHs, focusing on available methods of CP[c]Ph chemical synthesis. The most interesting structural feature of the CP[c]Ph is the presence of a pseudo fjord-region constructed by the cyclopentane ring. This compound can be treated either as a structurally similar one to B[c]Ph, or as a phenanthrene skeleton with an electrodonating alkyl substituent in the bay-region of the molecule. The second thread, providing available data on the adverse effects of CP[c]Ph compounds on cells and tissues of living organisms, mainly fish, improves our understanding of these possible environmental hazards. The data show that CP[c]Ph is less potent at inducing CYP1A gene expression in rainbow trout than benzo[a]pyrene (B[a]P), a well-known Ah-receptor agonist. Interestingly, the CP[c]Ph dependent up-regulation of CYP1A mRNA is positively correlated with the incidences of clastogenic changes in rainbow trout erythrocytes. CP[c]Ph has, comparably to B[a]P, a potential to repress expression of tumor suppressor p53, in the head kidney of rainbow trout. Furthermore, estrogen responsive genes in fish liver, ERα and VTG, are not induced by CP[c]Ph, suggesting that the compound has no endocrine disrupting potential. However, some CP[c]Phs show mutagenic activity when investigated in the Ames test, and exhibit genotoxic properties in in vitro micronucleus assay. The above characteristics suggest that CP-PAHs are chemicals of concern for which potential pathways of exposure should be further identified. PMID:23628509

  13. Theoretical study on magnetic coupling interaction for Cu(II) binuclear systems with extended bridging groups

    NASA Astrophysics Data System (ADS)

    Bi, Siwei; Liu, Chengbu; Hu, Haiquan; Zhang, Changqiao

    2001-12-01

    The magnetic coupling interaction for Cu(II) binuclear systems with bridging groups C2O4 2- , C2O2( NH) 2 2- ( cis), C2O2( NH) 2 2- ( trans) and C2S2( NH) 2 2- ( trans) was studied by the broken symmetry (BS) approach within the framework of the density functional theory (DFT). The influence of different coordination atoms and geometry on magnetic coupling interaction was theoretically analyzed. Both of the calculated and experimental results were compared. The variation trends of coupling interaction calculated are in agreement with experimental ones.

  14. Chromium-chromium interaction in a binuclear mixed-valent Cr(I)-Cr(II) complex.

    PubMed

    Alzamly, Ahmed; Gorelsky, Serge I; Gambarotta, Sandro; Korobkov, Ilia; Le Roy, Jennifer; Murugesu, Muralee

    2014-11-01

    A mixed-valent Cr(I)-Cr(II) binuclear complex, {κ(1),κ(2),κ(3)-N,P,P-cyclo[(Ph)PCH2N(CH2Ph)CH2]}2(CrCl2)[Cr(μ-Cl)(AlClMe2)]·4toluene (1), of a P2N2 cyclic ligand was obtained upon treatment of the chromium precursor with alkylaluminum. Complex 1 was accessible from either its trivalent or divalent precursors, and density functional theory calculations revealed the presence of only σ- and π-orbital interactions in the Cr-Cr bond. PMID:25310604

  15. Systems Biology Graphical Notation: Activity Flow language Level 1 Version 1.2.

    PubMed

    Mi, Huaiyu; Schreiber, Falk; Moodie, Stuart; Czauderna, Tobias; Demir, Emek; Haw, Robin; Luna, Augustin; Le Novère, Nicolas; Sorokin, Anatoly; Villéger, Alice

    2015-01-01

    The Systems Biological Graphical Notation (SBGN) is an international community effort for standardized graphical representations of biological pathways and networks. The goal of SBGN is to provide unambiguous pathway and network maps for readers with different scientific backgrounds as well as to support efficient and accurate exchange of biological knowledge between different research communities, industry, and other players in systems biology. Three SBGN languages, Process Description (PD), Entity Relationship (ER) and Activity Flow (AF), allow for the representation of different aspects of biological and biochemical systems at different levels of detail. The SBGN Activity Flow language represents the influences of activities among various entities within a network. Unlike SBGN PD and ER that focus on the entities and their relationships with others, SBGN AF puts the emphasis on the functions (or activities) performed by the entities, and their effects to the functions of the same or other entities. The nodes (elements) describe the biological activities of the entities, such as protein kinase activity, binding activity or receptor activity, which can be easily mapped to Gene Ontology molecular function terms. The edges (connections) provide descriptions of relationships (or influences) between the activities, e.g., positive influence and negative influence. Among all three languages of SBGN, AF is the closest to signaling pathways in biological literature and textbooks, but its well-defined semantics offer a superior precision in expressing biological knowledge. PMID:26528563

  16. Indolo[3,2-b]quinolines: Synthesis, Biological Evaluation and Structure Activity-Relationships

    PubMed Central

    Kumar, Eyunni V.K. Suresh; Etukala, Jagan R.; Ablordeppey, Seth Y.

    2013-01-01

    The tetracyclic indolo[3,2-b]quinoline ring system constitutes an important structural moiety in natural products exhibiting numerous biological activities. In particular, indolo [3, 2-b]quinoline, commonly known as linear quindo-line is of particular interest, because of its rigid structure and scope of derivatization. Although the core linear quindoline skeleton shows little or no activity in several biological systems, introduction of a methyl group on the N-5 atom leading to cryptolepine induces remarkable activity against a broad spectrum of biological targets. A number of analogs of quindoline and cryptolepine have been synthesized, incorporating various functional groups on the core quindoline skeleton leading to improved biological activities. In this review, we describe various synthetic methodologies leading to the quindoline scaffold, the biological activities and the structure activity relationships (SAR) of quindoline derivatives toward different disease states to give a better picture of the importance of this moiety in medicinal chemistry. PMID:18537709

  17. Crystal structure of human arginase I complexed with thiosemicarbazide reveals an unusual thiocarbonyl μ-sulfide ligand in the binuclear manganese cluster

    PubMed Central

    Di Costanzo, Luigi; Pique, Michael E.; Christianson, David W.

    2008-01-01

    The crystal structure of the human arginase I-thiosemicarbazide complex reveals an unusual thiocarbonyl μ-sulfide ligand in the binuclear manganese cluster. The C=S moiety of thiosemicarbazide bridges Mn2+A and Mn2+B with coordination distances of 2.6 Å and 2.4 Å, respectively. Otherwise, the binding of thiosemicarbazide to human arginase I does not cause any significant structural changes in the active site. The crystal structure of the unliganded enzyme reveals a hydrogen bonded water molecule that could support proton transfer between a μ-water molecule and H141 to regenerate the nucleophilic μ-hydroxide ion in the final step of catalysis. PMID:17469833

  18. Biologically Active Polymers from Spontaneous Carotenoid Oxidation: A New Frontier in Carotenoid Activity

    PubMed Central

    Johnston, James B.; Nickerson, James G.; Daroszewski, Janusz; Mogg, Trevor J.; Burton, Graham W.

    2014-01-01

    In animals carotenoids show biological activity unrelated to vitamin A that has been considered to arise directly from the behavior of the parent compound, particularly as an antioxidant. However, the very property that confers antioxidant activity on some carotenoids in plants also confers susceptibility to oxidative transformation. As an alternative, it has been suggested that carotenoid oxidative breakdown or metabolic products could be the actual agents of activity in animals. However, an important and neglected aspect of the behavior of the highly unsaturated carotenoids is their potential to undergo addition of oxygen to form copolymers. Recently we reported that spontaneous oxidation of ß-carotene transforms it into a product dominated by ß-carotene-oxygen copolymers. We now report that the polymeric product is biologically active. Results suggest an overall ability to prime innate immune function to more rapidly respond to subsequent microbial challenges. An underlying structural resemblance to sporopollenin, found in the outer shell of spores and pollen, may allow the polymer to modulate innate immune responses through interactions with the pattern recognition receptor system. Oxygen copolymer formation appears common to all carotenoids, is anticipated to be widespread, and the products may contribute to the health benefits of carotenoid-rich fruits and vegetables. PMID:25360750

  19. Biologically active polymers from spontaneous carotenoid oxidation: a new frontier in carotenoid activity.

    PubMed

    Johnston, James B; Nickerson, James G; Daroszewski, Janusz; Mogg, Trevor J; Burton, Graham W

    2014-01-01

    In animals carotenoids show biological activity unrelated to vitamin A that has been considered to arise directly from the behavior of the parent compound, particularly as an antioxidant. However, the very property that confers antioxidant activity on some carotenoids in plants also confers susceptibility to oxidative transformation. As an alternative, it has been suggested that carotenoid oxidative breakdown or metabolic products could be the actual agents of activity in animals. However, an important and neglected aspect of the behavior of the highly unsaturated carotenoids is their potential to undergo addition of oxygen to form copolymers. Recently we reported that spontaneous oxidation of ß-carotene transforms it into a product dominated by ß-carotene-oxygen copolymers. We now report that the polymeric product is biologically active. Results suggest an overall ability to prime innate immune function to more rapidly respond to subsequent microbial challenges. An underlying structural resemblance to sporopollenin, found in the outer shell of spores and pollen, may allow the polymer to modulate innate immune responses through interactions with the pattern recognition receptor system. Oxygen copolymer formation appears common to all carotenoids, is anticipated to be widespread, and the products may contribute to the health benefits of carotenoid-rich fruits and vegetables. PMID:25360750

  20. COMPUTER-ASSISTED STUDIES OF MOLECULAR STRUCTURE-BIOLOGICAL ACTIVITY RELATIONSHIPS

    EPA Science Inventory

    Computer-assisted methods can be used to investigate the relationships between the molecular structures of compounds and their biological activity. A number of approaches have been reported in the literature, including correlations of activity with substituent constants, conforma...

  1. Three Activities To Assist Biology Teachers in Presenting Conceptually Difficult Topics.

    ERIC Educational Resources Information Center

    Taylor, Neil; Tulip, David

    1997-01-01

    Outlines three activities for different areas of biology that can serve as motivators for students or as demonstrations. Each activity is easy to organize and uses available materials. Topics include evolution, anaerobic respiration, and heat loss. (DDR)

  2. Using Active Learning to Teach Concepts and Methods in Quantitative Biology.

    PubMed

    Waldrop, Lindsay D; Adolph, Stephen C; Diniz Behn, Cecilia G; Braley, Emily; Drew, Joshua A; Full, Robert J; Gross, Louis J; Jungck, John A; Kohler, Brynja; Prairie, Jennifer C; Shtylla, Blerta; Miller, Laura A

    2015-11-01

    This article provides a summary of the ideas discussed at the 2015 Annual Meeting of the Society for Integrative and Comparative Biology society-wide symposium on Leading Students and Faculty to Quantitative Biology through Active Learning. It also includes a brief review of the recent advancements in incorporating active learning approaches into quantitative biology classrooms. We begin with an overview of recent literature that shows that active learning can improve students' outcomes in Science, Technology, Engineering and Math Education disciplines. We then discuss how this approach can be particularly useful when teaching topics in quantitative biology. Next, we describe some of the recent initiatives to develop hands-on activities in quantitative biology at both the graduate and the undergraduate levels. Throughout the article we provide resources for educators who wish to integrate active learning and technology into their classrooms. PMID:26269460

  3. Oxo-group-14-element bond formation in binuclear uranium(V) Pacman complexes.

    PubMed

    Jones, Guy M; Arnold, Polly L; Love, Jason B

    2013-07-29

    Simple and versatile routes to the functionalization of uranyl-derived U(V)-oxo groups are presented. The oxo-lithiated, binuclear uranium(V)-oxo complexes [{(py)3LiOUO}2(L)] and [{(py)3LiOUO}(OUOSiMe3)(L)] were prepared by the direct combination of the uranyl(VI) silylamide "ate" complex [Li(py)2][(OUO)(N")3] (N" = N(SiMe3)2) with the polypyrrolic macrocycle H4L or the mononuclear uranyl (VI) Pacman complex [UO2(py)(H2L)], respectively. These oxo-metalated complexes display distinct U-O single and multiple bonding patterns and an axial/equatorial arrangement of oxo ligands. Their ready availability allows the direct functionalization of the uranyl oxo group leading to the binuclear uranium(V) oxo-stannylated complexes [{(R3Sn)OUO}2(L)] (R = nBu, Ph), which represent rare examples of mixed uranium/tin complexes. Also, uranium-oxo-group exchange occurred in reactions with [TiCl(OiPr)3] to form U-O-C bonds [{(py)3LiOUO}(OUOiPr)(L)] and [(iPrOUO)2(L)]. Overall, these represent the first family of uranium(V) complexes that are oxo-functionalised by Group 14 elements. PMID:23794441

  4. Synergy and destructive interferences between local magnetic anisotropies in binuclear complexes

    SciTech Connect

    Guihéry, Nathalie; Ruamps, Renaud; Maurice, Rémi

    2015-12-31

    Magnetic anisotropy is responsible for the single molecule magnet behavior of transition metal complexes. This behavior is characterized by a slow relaxation of the magnetization for low enough temperatures, and thus for a possible blocking of the magnetization. This bistable behavior can lead to possible technological applications in the domain of data storage or quantum computing. Therefore, the understanding of the microscopic origin of magnetic anisotropy has received a considerable interest during the last two decades. The presentation focuses on the determination of the anisotropy parameters of both mono-nuclear and bi-nuclear types of complexes and on the control and optimization of the anisotropic properties. The validity of the model Hamiltonians commonly used to characterize such complexes has been questioned and it is shown that neither the standard multispin Hamiltonian nor the giant spin Hamiltonian are appropriate for weakly coupled ions. Alternative models have been proposed and used to properly extract the relevant parameters. Rationalizations of the magnitude and nature of both local anisotropies of single ions and the molecular anisotropy of polynuclear complexes are provided. The synergy and interference effects between local magnetic anisotropies are studied in a series of binuclear complexes.

  5. Synergy and destructive interferences between local magnetic anisotropies in binuclear complexes

    NASA Astrophysics Data System (ADS)

    Guihéry, Nathalie; Ruamps, Renaud; Maurice, Rémi; de Graaf, Coen

    2015-12-01

    Magnetic anisotropy is responsible for the single molecule magnet behavior of transition metal complexes. This behavior is characterized by a slow relaxation of the magnetization for low enough temperatures, and thus for a possible blocking of the magnetization. This bistable behavior can lead to possible technological applications in the domain of data storage or quantum computing. Therefore, the understanding of the microscopic origin of magnetic anisotropy has received a considerable interest during the last two decades. The presentation focuses on the determination of the anisotropy parameters of both mono-nuclear and bi-nuclear types of complexes and on the control and optimization of the anisotropic properties. The validity of the model Hamiltonians commonly used to characterize such complexes has been questioned and it is shown that neither the standard multispin Hamiltonian nor the giant spin Hamiltonian are appropriate for weakly coupled ions. Alternative models have been proposed and used to properly extract the relevant parameters. Rationalizations of the magnitude and nature of both local anisotropies of single ions and the molecular anisotropy of polynuclear complexes are provided. The synergy and interference effects between local magnetic anisotropies are studied in a series of binuclear complexes.

  6. Synthesis of binuclear platinum complexes containing the ligands 8-naphthyridine, 2-aminopyridine, and 7-azaindolate. An experimental study of the steric hindrance of the bulky pentafluorophenyl ligands in the synthesis of binuclear complexes.

    PubMed

    Casas, José M; Diosdado, Beatriz E; Forniés, Juan; Martín, Antonio; Rueda, Angel J; Orpen, A Guy

    2008-10-01

    The bidentate N-donor ligands 2-aminopyridine (2-ampy), 7-azaindolate (aza) and 1,8-naphthyridine (napy) have been used to study the steric effect of pentafluorophenyl groups in the synthesis of binuclear platinum(II) complexes. The 2-ampy and aza ligands bridge two "Pt(C 6F 5) 2" fragments with Pt...Pt distances of 4.1 and 3.4 A, respectively (complexes 1 and 3). Under the same reaction conditions the napy ligand shows chelating behavior and makes the mononuclear complex ( A) highly reactive because of its strained coordination. One of the Pt-N bonds of the chelating complex is broken on reaction with HX {X = Cl ( 4), Br ( 5)} because of protonation while the anion X (-) occupies a created vacant site. The resulting mononuclear complex eliminates C 6F 5H when refluxed, and a binuclear complex ( 6) with two napy ligands bridging two "Pt(C 6F 5)Cl" fragments is obtained. The reaction of A with HPPh 2 affords a mononuclear complex ( 7) analogous to complexes 5 and 6, but reflux gives a binuclear complex ( 8) with the two napy ligands terminally bound and the PPh 2 groups bridging the "Pt(C 6F 5)napy" moieties. The reaction of A with HCCPh gives a binuclear complex; moreover, the final product does not depend on the ratio of complex A to HCCPh. Complexes 1, 4, 6, 9 have been structurally characterized by X-ray diffraction. PMID:18767797

  7. Crystal Structure of an Arginase-like Protein from Trypanosoma brucei That Evolved without a Binuclear Manganese Cluster

    PubMed Central

    2015-01-01

    The X-ray crystal structure of an arginase-like protein from the parasitic protozoan Trypanosoma brucei, designated TbARG, is reported at 1.80 and 2.38 Å resolution in its reduced and oxidized forms, respectively. The oxidized form of TbARG is a disulfide-linked hexamer that retains the overall architecture of a dimer of trimers in the reduced form. Intriguingly, TbARG does not contain metal ions in its putative active site, and amino acid sequence comparisons indicate that all but one of the residues required for coordination to the catalytically obligatory binuclear manganese cluster in other arginases are substituted here with residues incapable of metal ion coordination. Therefore, the structure of TbARG is the first of a member of the arginase/deacetylase superfamily that is not a metalloprotein. Although we show that metal binding activity is easily reconstituted in TbARG by site-directed mutagenesis and confirmed in X-ray crystal structures, it is curious that this protein and its parasitic orthologues evolved away from metal binding function. Knockout of the TbARG gene from the genome demonstrated that its function is not essential to cultured bloodstream-form T. brucei, and metabolomics analysis confirmed that the enzyme has no role in the conversion of l-arginine to l-ornithine in these cells. While the molecular function of TbARG remains enigmatic, the fact that the T. brucei genome encodes only this protein and not a functional arginase indicates that the parasite must import l-ornithine from its host to provide a source of substrate for ornithine decarboxylase in the polyamine biosynthetic pathway, an active target for the development of antiparasitic drugs. PMID:25536859

  8. Potential biological activities and bioavailability of alfrutamide and caffedymine

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alfrutamide and caffedymine are clovamide-type phenolic amides whose analogues are found in numerous plants including garlic and cocoa. However, potential health effects of the amides are largely unknown. For last ten years, several amides have been synthesized and their potential biological activi...

  9. Synthesis, biological activities, and quantitative structure-activity relationship (QSAR) study of novel camptothecin analogues.

    PubMed

    Wu, Dan; Zhang, Shao-Yong; Liu, Ying-Qian; Wu, Xiao-Bing; Zhu, Gao-Xiang; Zhang, Yan; Wei, Wei; Liu, Huan-Xiang; Chen, An-Liang

    2015-01-01

    In continuation of our program aimed at the development of natural product-based pesticidal agents, three series of novel camptothecin derivatives were designed, synthesized, and evaluated for their biological activities against T. Cinnabarinus, B. brassicae, and B. xylophilus. All of the derivatives showed good-to-excellent activity against three insect species tested, with LC50 values ranging from 0.00761 to 0.35496 mmol/L. Remarkably, all of the compounds were more potent than CPT against T. Cinnabarinus, and compounds 4d and 4c displayed superior activity (LC50 0.00761 mmol/L and 0.00942 mmol/L, respectively) compared with CPT (LC50 0.19719 mmol/L) against T. Cinnabarinus. Based on the observed bioactivities, preliminary structure-activity relationship (SAR) correlations were also discussed. Furthermore, a three-dimensional quantitative structure-activity relationship (3D-QSAR) model using comparative molecular field analysis (CoMFA) was built. The model gave statistically significant results with the cross-validated q2 values of 0.580 and correlation coefficient r2 of 0.991 and  of 0.993. The QSAR analysis indicated that the size of the substituents play an important in the activity of 7-modified camptothecin derivatives. These findings will pave the way for further design, structural optimization, and development of camptothecin-derived compounds as pesticidal agents. PMID:25985362

  10. Reconstitution of the water-oxidizing complex in manganese-depleted photosystem II preparations using synthetic binuclear Mn(II) and Mn(IV) complexes: production of hydrogen peroxide.

    PubMed

    Nagata, Toshi; Nagasawa, Takayuki; Zharmukhamedov, Sergei K; Klimov, Vyacheslav V; Allakhverdiev, Suleyman I

    2007-01-01

    Reconstitution of Mn-depleted PSII particles with synthetic binuclear Mn complexes (one Mn(II)(2) complex and one Mn(IV)(2) complex) was examined. In both cases the electron-transfer rates in the reconstituted systems were found to be up to 75-82% of that measured in native PSII but the oxygen evolution activity remained lower (<5-40%). However, hydrogen peroxide was also produced by the reconstituted samples. These samples therefore represent a new type of reconstituted PSII that generates hydrogen peroxide as the final product in reconstituted PSII centers. PMID:17437183

  11. Phenolate based metallomacrocyclic xanthate complexes of Co(II)/Cu(II) and their exclusive deployment in [2 : 2] binuclear N,O-Schiff base macrocycle formation and in vitro anticancer studies.

    PubMed

    Singh, Vinay K; Kadu, Rahul; Roy, Hetal; Raghavaiah, Pallepogu; Mobin, Shaikh M

    2016-01-28

    Potassium salts of phenolate based polydentate xanthate ligands 4,4'-bis(2-dithiocarbonatobenzylideneamino)diphenyl ether () and 4,4'-bis(2-dithiocarbonatonaphthylmethylideneamino)diphenyl ether () have been synthesized and characterized, prior to use. The reaction of or with M(OAc)2 in Et3N affords access to a rare series of binuclear metallomacrocyclic xanthate complexes of the type [M2-μ(2)-bis-(κ(2)S,S-xan(1)/xan(2))] () which quickly forms [2 : 2] binuclear N,O-bidentate Schiff base macrocyclic complexes of the type [M2-μ(2)-bis-(κ(2)N,O-L(1)/L(2))] ( = 4,4'-bis(2-hydroxybenzylideneamino)diphenyl ether, = 4,4'-bis(2-hydroxynaphthylmethylidene-amino)diphenyl ether) via evolution of CS2 in solution. The compounds were characterized by microanalysis, relevant spectroscopy (FT-IR, UV-visible), mass spectrometry (ESI-MS), and powder and single crystal XRD techniques. In vitro anticancer activity of all the compounds was evaluated against HEP 3B (hepatoma) and IMR 32 (neuroblastoma) by the MTT assay. Remarkably, the binuclear copper(ii) xanthate complexes were found to be extremely active against both the cell lines (IC50: 8.1 ± 0.8 μM (), 8.8 ± 1.7 μM () against HEP 3B and 1.9 ± 0.3 μM () and 7.3 ± 0.6 μM () against IMR 32) and this projects them as good candidates for potent antitumor agents and the IC50 values confirm their better potency than the reference drug cisplatin. The flow-cytometric density plot illustrates the induction of apoptosis in HEP 3B and IMR 32 cells after treatment with , , , and . PMID:26674056

  12. Physicochemical and porosity characteristics of thermally regenerated activated carbon polluted with biological activated carbon process.

    PubMed

    Dong, Lihua; Liu, Wenjun; Jiang, Renfu; Wang, Zhansheng

    2014-11-01

    The characteristics of thermally regenerated activated carbon (AC) polluted with biological activated carbon (BAC) process were investigated. The results showed that the true micropore and sub-micropore volume, pH value, bulk density, and hardness of regenerated AC decreased compared to the virgin AC, but the total pore volume increased. XPS analysis displayed that the ash contents of Al, Si, and Ca in the regenerated AC respectively increased by 3.83%, 2.62% and 1.8%. FTIR spectrum showed that the surface functional groups of virgin and regenerated AC did not change significantly. Pore size distributions indicated that the AC regeneration process resulted in the decrease of micropore and macropore (D>10 μm) volume and the increase of mesopore and macropore (0.1 μmbiological waste (spent AC) from BAC process. PMID:25203235

  13. A novel binuclear palladacycle complex inhibits melanoma growth in vitro and in vivo through apoptosis and autophagy.

    PubMed

    Aliwaini, Saeb; Swarts, Andrew J; Blanckenberg, Angelique; Mapolie, Selwyn; Prince, Sharon

    2013-12-15

    Malignant melanoma is an aggressive skin cancer and it is reported to be the most treatment-resistant human cancer. Here we describe the anti-tumour activity of a novel binuclear palladacycle complex (AJ-5) in vertical growth phase (ME1402) and metastatic (WM1158) melanoma cell lines. We show that compared to normal control cell lines, AJ-5 is more effective in inhibiting the proliferation of ME1402 and WM1158 melanoma cells with IC50 values of 0.19 and 0.20μM, respectively. Flow cytometry analyses showed that AJ-5 induced apoptosis (sub-G1 peak) which was confirmed by Annexin V-FITC/propidium iodide double-staining, nuclear fragmentation and an increase in the levels of PARP cleavage. Furthermore, AJ-5 was shown to induce both intrinsic and extrinsic apoptotic pathways as measured by PUMA, Bax and active caspases. Interestingly, AJ-5 treatment also simultaneously induced the formation of autophagosomes and led to an increase in the autophagy markers LC3II and Beclin1. Inhibition of autophagy reduced AJ-5 cytotoxicity suggesting that AJ-5 induced autophagy was a cell death and not cell survival mechanism. Moreover we show that AJ-5 induces the ATM-CHK2 DNA damage pathway and that its anti-tumour function is mediated by the p38 and ERK1/2 signalling pathways. Importantly, AJ-5 treatment efficiently reduced tumour growth in melanoma bearing mice and induced high levels of autophagy and apoptosis markers. Together these findings suggest that AJ-5 may be an effective chemotherapeutic drug in the treatment of melanoma, a highly aggressive and intractable cancer. PMID:24099796

  14. [Development of new biologically active dressings and methodology of their use].

    PubMed

    Adamian, A A; Dobysh, S V; Kilimchuk, L E; Shandurenko, I N; Chekmareva, I A

    2004-01-01

    Results of development of new biologically active dressings and up-to-date methodology of local treatment of wounds (based on their differential application according to phase and features of wound process) are demonstrated. Data about main properties and specific activity of new biologically active dressings based on natural and synthetic polymers with immobilized drugs are presented. Future trends and efficacy of their appliance in complex treatment of purulent and necrotic wounds are demonstrated. PMID:15699950

  15. Collapse of the EPR fine structure of a one-dimensional array of weakly interacting binuclear units: A dimensional quantum phase transition

    NASA Astrophysics Data System (ADS)

    Calvo, Rafael; Abud, Julián E.; Sartoris, Rosana P.; Santana, Ricardo C.

    2011-09-01

    Binuclear (also called dimeric) compounds with pairs of antiferromagnetically coupled spins ½, S1 and S2 (Hex = -J0 S1.S2, with J0<0 for antiferromagnets), have been around for ˜60 years, providing roots to the field of molecular magnetism. In addition, as reported in recent years, weak interactions between binuclear units in a crystalline network give rise to interesting systems of interacting bosons having an energy gap, which are important in the study of quantum phenomena in many body systems coupled by stochastic distributions of interactions. Binuclear compounds have gained new relevance in the last decade with the observation of Bose-Einstein condensation. In this work, we use electron paramagnetic resonance (EPR) to study the role of weak inter-binuclear exchange couplings J’ (|J’| ≪|J0|) in the spectra, elementary excitations, and spin dynamics of a one-dimensional (1-D) array of antiferromagnetic (AFM) binuclear units in the hybrid (organic-inorganic) CuII compound [Cu(CH3COO)(phen)(H2O)]2·(NO3)2·4H2O. In this material, the acetate (CH3COO)- anion supports the intra-binuclear exchange coupling J0, and the stacking of the (phen) = 1,10-phenanthroline rings of neighbor units supports the inter-binuclear interactions J', giving rise to well-isolated chains. This has advantages over other binuclear compounds studied previously because magnetically equal units are arranged in a 1-D spatial arrangement along the direction of their symmetry axis, simplifying the analysis of the data and allowing a simpler treatment. In addition, single crystals of good quality allow detailed EPR experiments.EPR spectra were collected at ˜33.8 and ˜9.4-9.8 GHz in oriented single crystals at room temperature and in powder samples at temperatures (T) between 10 and 300 K. By varying the energy levels of the binuclear units with the magnetic field orientation, or changing the population of the excited triplet state with temperature and, consequently, the effective

  16. Biologically Active Chorionic Gonadotropin: Synthesis by the Human Fetus

    NASA Astrophysics Data System (ADS)

    McGregor, W. G.; Kuhn, R. W.; Jaffe, R. B.

    1983-04-01

    The kidney, and to a slight extent the liver, of human fetuses were found to synthesize and secrete the α subunit common to glycoprotein hormones. Fetal lung and muscle did not synthesize this protein. Since fetal kidney and liver were previously found to synthesize β chorionic gonadotropin, their ability to synthesize bioactive chorionic gonadotropin was also determined. The newly synthesized hormone bound to mouse Leydig cells and elicited a biological response: namely, the synthesis of testosterone. These results suggest that the human fetus may participate in metabolic homeostasis during its development.

  17. Low Budget Biology 3: A Collection of Low Cost Labs and Activities.

    ERIC Educational Resources Information Center

    Wartski, Bert; Wartski, Lynn Marie

    This document contains biology labs, demonstrations, and activities that use low budget materials. The goal is to get students involved in the learning process by experiencing biology. Each lab has a teacher preparation section which outlines the purpose of the lab, some basic information, a list of materials , and how to prepare the different…

  18. An Introduction to Biological Modeling Using Coin Flips to Predict the Outcome of a Diffusion Activity

    ERIC Educational Resources Information Center

    Butcher, Greg Q.; Rodriguez, Juan; Chirhart, Scott; Messina, Troy C.

    2016-01-01

    In order to increase students' awareness for and comfort with mathematical modeling of biological processes, and increase their understanding of diffusion, the following lab was developed for use in 100-level, majors/non-majors biology and neuroscience courses. The activity begins with generation of a data set that uses coin-flips to replicate…

  19. Binuclear ruthenium(III) bis(thiosemicarbazone) complexes: synthesis, spectral, electrochemical studies and catalytic oxidation of alcohol.

    PubMed

    Mohamed Subarkhan, M; Ramesh, R

    2015-03-01

    A new series of binuclear ruthenium(III) thiosemicarbazone complexes of general formula [(EPh3)2(X)2Ru-L-Ru(X)2(EPh3)2] (where E=P or As; X=Cl or Br; L=NS chelating bis(thiosemicarbazone ligands) has been synthesized and characterized by analytical and spectral (FT-IR, UV-Vis and EPR). IR spectra show that the thiosemicarbazones behave as monoanionic bidentate ligands coordinating through the azomethine nitrogen and thiolate sulphur. The electronic spectra of the complexes indicate that the presence of d-d and intense LMCT transitions in the visible region. The complexes are paramagnetic (low spin d(5)) in nature and all the complexes show rhombic distortion around the ruthenium ion with three different 'g' values (gx≠gy≠gz) at 77K. All the complexes are redox active and exhibit an irreversible metal centered redox processes (Ru(III)-Ru(III)/Ru(IV)-Ru(IV); Ru(III)-Ru(III)/Ru(II)-Ru(II)) within the potential range of 0.38-0.86V and -0.39 to -0.66 V respectively, versus Ag/AgCl. Further, the catalytic efficiency of one of the complexes [Ru2Cl2(AsPh3)4(L1)] (4) has been investigated in the case of oxidation of primary and secondary alcohols into their corresponding aldehydes and ketones in the presence of N-methylmorpholine-N-oxide(NMO) as co-oxidant. The formation of high valent Ru(V)O species is proposed as catalytic intermediate for the catalytic cycle. PMID:25498823

  20. Binuclear ruthenium(III) bis(thiosemicarbazone) complexes: Synthesis, spectral, electrochemical studies and catalytic oxidation of alcohol

    NASA Astrophysics Data System (ADS)

    Mohamed Subarkhan, M.; Ramesh, R.

    2015-03-01

    A new series of binuclear ruthenium(III) thiosemicarbazone complexes of general formula [(EPh3)2(X)2Ru-L-Ru(X)2(EPh3)2] (where E = P or As; X = Cl or Br; L = NS chelating bis(thiosemicarbazone ligands) has been synthesized and characterized by analytical and spectral (FT-IR, UV-Vis and EPR). IR spectra show that the thiosemicarbazones behave as monoanionic bidentate ligands coordinating through the azomethine nitrogen and thiolate sulphur. The electronic spectra of the complexes indicate that the presence of d-d and intense LMCT transitions in the visible region. The complexes are paramagnetic (low spin d5) in nature and all the complexes show rhombic distortion around the ruthenium ion with three different 'g' values (gx ≠ gy ≠ gz) at 77 K. All the complexes are redox active and exhibit an irreversible metal centered redox processes (RuIII-RuIII/RuIV-RuIV; RuIII-RuIII/RuII-RuII) within the potential range of 0.38-0.86 V and -0.39 to -0.66 V respectively, versus Ag/AgCl. Further, the catalytic efficiency of one of the complexes [Ru2Cl2(AsPh3)4(L1)] (4) has been investigated in the case of oxidation of primary and secondary alcohols into their corresponding aldehydes and ketones in the presence of N-methylmorpholine-N-oxide(NMO) as co-oxidant. The formation of high valent RuVdbnd O species is proposed as catalytic intermediate for the catalytic cycle.

  1. Synthesis, biological activities and structure-activity relationships for new avermectin analogues.

    PubMed

    Zhang, Jian; Nan, Xiang; Yu, Hai-Tao; Cheng, Pi-Le; Zhang, Yan; Liu, Ying-Qian; Zhang, Shao-Yong; Hu, Guan-Fang; Liu, Huanxiang; Chen, An-Liang

    2016-10-01

    In an effort to discover new molecules with good insecticidal activities, more than 40 new avermectin derivatives were synthesized and evaluated for their biological activities against three species of arachnids, insects and nematodes, namely, Tetranychus Cinnabarinus, Aphis craccivora and Bursaphelenchus xylophilus. All the tested compounds showed potent inhibitory activities against three insect species. Notably, the majority of compounds exhibited high selectivity against T. cinnabarinus, some of which were much better in comparison with avermectin. Especially compounds 9j (LC50: 0.005 μM) and 16d (LC50: 0.002 μM) were 2.5- and 4.7-fold more active than avermectin (LC50: 0.013 μM), respectively, against T. cinnabarinus. Moreover, compounds 9b, 9d-f, 9h, 9j, 9l, 9n, 9p, 9r, 9v and 17d showed superior activities with LC50 values of 2.959-5.013 μM compared to that of 1 (LC50: 6.746 μM) against B. xylophilus. Meanwhile, the insecticidal activities of compounds 9f, 9g, 9h, and 9m against A. craccivora were 7-8 times better than that of avermectin, with LC50 values of 7.744, 5.634, 6.809, 7.939 and 52.234 μM, respectively. Furthermore, QSAR analysis showed that the molecular shape, size, connectivity degree and electronic distribution of avermectin analogues had substantial effects on insecticidal potency. These preliminary results provided useful insight in guiding further modifications of avermectin in the development of potential new insecticides. PMID:27318119

  2. Some biologically active oxovanadium(IV) complexes of triazole derived Schiff bases: their synthesis, characterization and biological properties.

    PubMed

    Chohan, Zahid H; Sumrra, Sajjad H

    2010-10-01

    A series of biologically active oxovanadium(IV) complexes of triazole derived Schiff bases L(1)-L(5) have been synthesized and characterized by their physical, analytical, and spectral data. The synthesized ligands potentially act as bidentate, in which the oxygen of furfural and nitrogen of azomethine coordinate with the oxovanadium atom to give a stoichiometry of vanadyl complexes 1:2 (M:L) in a square-pyramidal geometry. In vitro antibacterial and antifungal activities on different species of pathogenic bacteria (E. coli, S. flexneri, P. aeruginosa, S. typhi, S. aureus, and B. subtilis) and fungi (T. longifusus, C. albicans, A. flavus, M. canis, F. solani, and C. glabrata) have been studied. All compounds showed moderate to significant antibacterial activity against one or more bacterial strains and good antifungal activity against most of the fungal strains. The brine shrimp bioassay was also carried out to check the cytotoxicity of coordinated and uncoordinated synthesized compounds. PMID:20429776

  3. FINAL REPORT. CONTROL OF BIOLOGICALLY ACTIVE DEGRADATION ZONES BY VERTICAL HETEROGENEITY: APPLICATIONS IN FRACTURED MEDIA

    EPA Science Inventory

    The key objective of this research was to determine the distribution of biologically active contaminant degradation zones in a fractured, subsurface medium with respect to vertical heterogeneities. Our expectation was that
    hydrogeological properties would determine the size, d...

  4. Activation of PPARδ: from computer modelling to biological effects.

    PubMed

    Kahremany, Shirin; Livne, Ariela; Gruzman, Arie; Senderowitz, Hanoch; Sasson, Shlomo

    2015-02-01

    PPARδ is a ligand-activated receptor that dimerizes with another nuclear receptor of the retinoic acid receptor family. The dimers interact with other co-activator proteins and form active complexes that bind to PPAR response elements and promote transcription of genes involved in lipid metabolism. It appears that various natural fatty acids and their metabolites serve as endogenous activators of PPARδ; however, there is no consensus in the literature on the nature of the prime activators of the receptor. In vitro and cell-based assays of PPARδ activation by fatty acids and their derivatives often produce conflicting results. The search for synthetic and selective PPARδ agonists, which may be pharmacologically useful, is intense. Current rational modelling used to obtain such compounds relies mostly on crystal structures of synthetic PPARδ ligands with the recombinant ligand binding domain (LBD) of the receptor. Here, we introduce an original computational prediction model for ligand binding to PPARδ LBD. The model was built based on EC50 data of 16 ligands with available crystal structures and validated by calculating binding probabilities of 82 different natural and synthetic compounds from the literature. These compounds were independently tested in cell-free and cell-based assays for their capacity to bind or activate PPARδ, leading to prediction accuracy of between 70% and 93% (depending on ligand type). This new computational tool could therefore be used in the search for natural and synthetic agonists of the receptor. PMID:25255770

  5. Synthesis and antiplatelet activity of antithrombotic thiourea compounds: biological and structure-activity relationship studies.

    PubMed

    Lourenço, André Luiz; Saito, Max Seidy; Dorneles, Luís Eduardo Gomes; Viana, Gil Mendes; Sathler, Plínio Cunha; Aguiar, Lúcia Cruz de Sequeira; de Pádula, Marcelo; Domingos, Thaisa Francielle Souza; Fraga, Aline Guerra Manssour; Rodrigues, Carlos Rangel; de Sousa, Valeria Pereira; Castro, Helena Carla; Cabral, Lucio Mendes

    2015-01-01

    The incidence of hematological disorders has increased steadily in Western countries despite the advances in drug development. The high expression of the multi-resistance protein 4 in patients with transitory aspirin resistance, points to the importance of finding new molecules, including those that are not affected by these proteins. In this work, we describe the synthesis and biological evaluation of a series of N,N'-disubstituted thioureas derivatives using in vitro and in silico approaches. New designed compounds inhibit the arachidonic acid pathway in human platelets. The most active thioureas (compounds 3d, 3i, 3m and 3p) displayed IC50 values ranging from 29 to 84 µM with direct influence over in vitro PGE2 and TXA2 formation. In silico evaluation of these compounds suggests that direct blockage of the tyrosyl-radical at the COX-1 active site is achieved by strong hydrophobic contacts as well as electrostatic interactions. A low toxicity profile of this series was observed through hemolytic, genotoxic and mutagenic assays. The most active thioureas were able to reduce both PGE2 and TXB2 production in human platelets, suggesting a direct inhibition of COX-1. These results reinforce their promising profile as lead antiplatelet agents for further in vivo experimental investigations. PMID:25903367

  6. Capturing Biological Activity in Natural Product Fragments by Chemical Synthesis

    PubMed Central

    Crane, Erika A.

    2016-01-01

    Abstract Natural products have had an immense influence on science and have directly led to the introduction of many drugs. Organic chemistry, and its unique ability to tailor natural products through synthesis, provides an extraordinary approach to unlock the full potential of natural products. In this Review, an approach based on natural product derived fragments is presented that can successfully address some of the current challenges in drug discovery. These fragments often display significantly reduced molecular weights, reduced structural complexity, a reduced number of synthetic steps, while retaining or even improving key biological parameters such as potency or selectivity. Examples from various stages of the drug development process up to the clinic are presented. In addition, this process can be leveraged by recent developments such as genome mining, antibody–drug conjugates, and computational approaches. All these concepts have the potential to identify the next generation of drug candidates inspired by natural products. PMID:26833854

  7. Synthesis of four binuclear copper(II) complexes: Structure, anticancer properties and anticancer mechanism.

    PubMed

    Qi, Jinxu; Liang, Shichu; Gou, Yi; Zhang, Zhenlei; Zhou, Zuping; Yang, Feng; Liang, Hong

    2015-01-01

    Copper (Cu) compounds are a promising candidate for next generation metal anticancer drugs and have been extensively studied. Therefore, four binuclear copper(II) compounds derived from Schiff base thiosemicarbazones (L1-L4), namely [CuCl(L1)]2 (C1), [CuNO3(L2)]2 (C2), [Cu(NCS) (L3)]2 (C3) and [Cu(CH3COO) (L4)]2 (C4) were synthesized and characterized. Four of these compounds showed very high cytotoxicity to cancer cell lines in vitro. These Cu(II) compounds strongly promoted the apoptosis of BEL-7404 cells. The formation of reactive oxygen species (ROS), change in mitochondrial membrane potential and western blot analysis revealed that Cu compounds could induce cancer cell apoptosis through the intrinsic ROS-mediated mitochondrial pathway accompanied by the regulation of Bcl-2 family proteins. PMID:25899339

  8. Activated Biological Filters (ABF Towers). Student Manual. Biological Treatment Process Control.

    ERIC Educational Resources Information Center

    Wooley, John F.

    This student manual contains textual material for a two-lesson unit on activated bio-filters (ABF). The first lesson (the sewage treatment plant) examines those process units that are unique to the ABF system. The lesson includes a review of the structural components of the ABF system and their functions and a discussion of several operational…

  9. Activated Biological Filters (ABF Towers). Instructor's Guide. Biological Treatment Process Control.

    ERIC Educational Resources Information Center

    Wooley, John F.

    This instructor's manual contains materials needed to teach a two-lesson unit on activated bio-filters (ABF). These materials include: (1) an overview of the two lessons; (2) lesson plans; (3) lecture outlines (keyed to a set of slides designed for use with the lessons); (4) overhead transparency masters; (5) worksheets for each lesson (with…

  10. Biological activity of a polypeptide modulator of TRPV1 receptor.

    PubMed

    Dyachenko, I A; Andreev, Ya A; Logashina, Yu A; Murashev, A N; Grishin, E V

    2015-11-01

    This paper presents data on the activity of a new APHC2 polypeptide modulator of TRPV1 receptors, which was isolated from the sea anemone Heteractis crispa. It has been shown that APHC2 has an analgesic activity, does not impair normal motor activity, and does not change body temperature of experimental animals, which has a great practical value for design of potent analgesics of a new generation. Further study of the characteristics of binding of the polypeptide to the TRPV1 receptor may show approaches to the development of other antagonists of this receptor that do not influence the body temperature. PMID:26725234

  11. Biological Activities of 2-Mercaptobenzothiazole Derivatives: A Review

    PubMed Central

    Azam, Mohammed Afzal; Suresh, Bhojraj

    2012-01-01

    2-Mercaptobenzothiazoles are an important class of bioactive and industrially important organic compounds. These compounds are reported for their antimicrobial and antifungal activities, and are subsequently highlighted as a potent mechanism-based inhibitor of several enzymes like acyl coenzyme A cholesterol acyltransferase, monoamine oxidase, heat shock protein 90, cathepsin D, and c-Jun N-terminal kinases. These derivatives are also known to possess antitubercular, anti-inflammatory, antitumor, amoebic, antiparkinsonian, anthelmintic, antihypertensive, antihyperlipidemic, antiulcer, chemoprotective, and selective CCR3 receptor antagonist activity. This present review article focuses on the pharmacological profile of 2-mercaptobenzothiazoles with their potential activities. PMID:23264933

  12. CHARACTERIZATION ADN BIOLOGICAL ACTIVITY OF SECONDARY METABOLITES FROM ARMILLARIA TABESCENS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ethyl acetate extracts from liquid cultures of Armillaria tabescens showed good antimicrobial activity against Candida albicans, Cryptococcus neoformans, Escherichia coli and Mycobacterium intracellulare. Chemical analyses of extract constituents led to the isolation and identification of two new co...

  13. Biological Studies in Childhood Schizophrenia: Plasma and RBC Cholinesterase Activity

    ERIC Educational Resources Information Center

    Lucas, Alexander R.; And Others

    1971-01-01

    A comparison of plasma (pseudo) cholinesterase and erythrocyte (true) cholinesterase activity in 16 male childhood schizophrenic patients and 16 male nonpsychotic hospitalized controls revealed no significant differences between the two groups. (Author)

  14. BIOLOGICAL VARIABILITY AND THE INFLUENCE OF STRESS ON CHOLINESTERASE ACTIVITY

    EPA Science Inventory

    Normal activity of brain and plasma cholinesterase in higher vertebrates is known to be affected by age, genetics, circadian rhythms, sex, endocrine function, and reproductive status. arious stressors (e.g., nutritional plane, ambient temperature, disease) have also been demonstr...

  15. [Biologically active food supplements as sources of flavonoids, tannins and dietary fibers].

    PubMed

    Kosheleva, O V; Berketova, L V

    2011-01-01

    The content of some biologically active substances such as bioflavonoids, tannins and dietary fiber in various type of biologically active additive was analyzed. The results are shown that the content of bioflavonoids ranger from 26.0 to 3970.0 mg%, tannins--from 1.19 to 857.0 mg%, insoluble dietary fiber--from 4.56 to 67.89% and soluble dietary fiber from 1.0 to 66.8%. PMID:22238949

  16. π-π Stacking and ferromagnetic coupling mechanism on a binuclear Cu(II) complex.

    PubMed

    Chi, Yan-Hui; Yu, Li; Shi, Jing-Min; Zhang, Yi-Quan; Hu, Tai-Qiu; Zhang, Gui-Qiu; Shi, Wei; Cheng, Peng

    2011-02-21

    The ferromagnetic couplings were observed in an unpublished crystal that consists of binuclear copper(II) complexes, namely, [Cu(2)(μ(1,3)-SCN)(2)(PhenOH)(OCH(3))(2)(HOCH(3))(2)] (PhenOH = 2-hydroxy-1,10-phenanthroline), and in the binuclear complex Cu(ii) ion assumes a distorted octahedral geometry and thiocyanate anion functions as a μ(1,3)-SCN(-) equatorial-axial (EA) bridging ligand. The analysis for the crystal structure indicates that there are three types of magnetic coupling pathways, in which two pathways involve π-π stacking between the adjacent complexes and the third one is the μ(1,3)-SCN(-) bridged pathway. The fitting for the data of the variable-temperature magnetic susceptibilities shows that there is a ferromagnetic coupling between adjacent Cu(II) ions with J = 50.02 cm(-1). Theoretical calculations reveal that the two types of π-π stacking resulted in ferromagnetic couplings with J = 4.16 cm(-1) and J = 2.75 cm(-1), respectively, and the bridged thiocyanate anions pathway led to a weaker ferromagnetic interaction with J = 0.88 cm(-1). The theoretical calculations also indicate that the ferromagnetic coupling sign from the two types of π-π stacking does not accord with McConnell I spin-polarization mechanism. The analysis for the Wiberg bond indexes that originate from the π-π stacking atoms indicates that the Wiberg bond indexes are relevant to the associated magnetic coupling magnitude and the Wiberg bond index is one of the key factors that dominates the associated magnetic coupling magnitude. PMID:21212898

  17. Asymmetric Synthesis of Enantiomerically Pure Mono- and Binuclear Bis(cyclometalated) Iridium(III) Complexes.

    PubMed

    Yao, Su-Yang; Ou, Yan-Ling; Ye, Bao-Hui

    2016-06-20

    Chiral precursors Λ-[Ir(ppy)2(l-pro)] (Λ-L, where ppy is 2-phenylpyridine; pro is proline), Λ-[Ir(ppy)2(MeCN)2](PF6) (Λ-1), Δ-[Ir(ppy)2(d-pro)] (Δ-D), and Δ-[Ir(ppy)2(MeCN)2](PF6) (Δ-1) were synthesized from rac-[(Ir(ppy)2)2Cl2] and l-pro or d-pro by means of the auxiliary ligand strategy with 99% de values. The enantiopure mono complexes Λ/Δ-[Ir(ppy)2(L)](PF6) (L is 2,2'-bipyridine, Λ/Δ-2; L is 2,2'-dipyrimidine (dpm), Λ/Δ-3; L is 2,2'-bibenzimidazole (H2bbim), Λ/Δ-4) with 99% ee values and binuclear complexes ΛΛ/ΔΔ-[(Ir(ppy)2)2(dpm)](PF6)2 (ΛΛ-5 and ΔΔ-5) and ΛΛ/ΔΔ-[(Ir(ppy)2)2(bbim)] (ΛΛ-6 and ΔΔ-6) with 99% de values were synthesized in one step using the corresponding chiral precursors. The absolute configurations at Ir(III) centers of precursor Δ-1, mononuclear Λ-3, and binuclear ΔΔ-6 were confirmed by single-crystal structural analysis and characterized by circular dichroism (CD) spectroscopy. The correlation between the absolute configuration at Ir(III) center and CD spectra was established. The configurations at Ir(III) centers are stable during the reactions, and the chiral precursors can be used for the asymmetric synthesis of enantiomerically pure mono- and polynuclear Ir(III) complexes. Moreover, meso ΛΔ-[(Ir(ppy)2)2(dpm)](PF6)2 (meso-5) and ΛΔ-[(Ir(ppy)2)2(bbim)] (meso-6) were also synthesized using these precursors. PMID:27280959

  18. Assessing the Biological Activity of the Glucan Phosphatase Laforin.

    PubMed

    Romá-Mateo, Carlos; Raththagala, Madushi; Gentry, Mathew S; Sanz, Pascual

    2016-01-01

    Glucan phosphatases are a recently discovered family of enzymes that dephosphorylate either starch or glycogen and are essential for proper starch metabolism in plants and glycogen metabolism in humans. Mutations in the gene encoding the only human glucan phosphatase, laforin, result in the fatal, neurodegenerative, epilepsy known as Lafora disease. Here, we describe phosphatase assays to assess both generic laforin phosphatase activity and laforin's unique glycogen phosphatase activity. PMID:27514803

  19. Design, Synthesis, and Biological Activity of Isosyringolin A.

    PubMed

    Kitahata, Shun; Chiba, Takuya; Yoshida, Takashi; Ri, Masaki; Iida, Shinsuke; Matsuda, Akira; Ichikawa, Satoshi

    2016-05-01

    Isosyringolin A, which is an isomer of the proteasome-inhibiting natural product syringolin A, was designed and synthesized to develop analogues that are step economical and synthetically accessible in a practical manner. It was revealed that isosyringolin A exhibited proteasome-inhibitory activity comparable to that of syringolin A and that its derivatization leads to great enhancement in its proteasome inhibitory activity as well as its cytotoxicity against human myeloma cells. PMID:27123978

  20. Using Active Learning in a Studio Classroom to Teach Molecular Biology

    ERIC Educational Resources Information Center

    Nogaj, Luiza A.

    2013-01-01

    This article describes the conversion of a lecture-based molecular biology course into an active learning environment in a studio classroom. Specific assignments and activities are provided as examples. The goal of these activities is to involve students in collaborative learning, teach them how to participate in the learning process, and give…

  1. Low Budget Biology. A Collection of Low Cost Labs and Activities.

    ERIC Educational Resources Information Center

    Wartski, Bert; Wartski, Lynn Marie

    This document contains a collection of low cost labs and activities. The activities are organized into the following units: Chemistry; Microbiology; DNA to Chromosomes; Genetics; Evolution; Classification, Protist, and Fungus; Plant; Invertebrate; Human Biology; and Ecology and Miscellaneous. Some of the activities within these units include: (1)…

  2. Biological Activities of Aerial Parts Extracts of Euphorbia characias

    PubMed Central

    Pisano, Maria Barbara; Cosentino, Sofia; Viale, Silvia; Spanò, Delia; Corona, Angela; Esposito, Francesca; Tramontano, Enzo; Montoro, Paola; Tuberoso, Carlo Ignazio Giovanni; Medda, Rosaria; Pintus, Francesca

    2016-01-01

    The aim of the present study was to evaluate antioxidant, antimicrobial, anti-HIV, and cholinesterase inhibitory activities of aqueous and alcoholic extracts from leaves, stems, and flowers of Euphorbia characias. The extracts showed a high antioxidant activity and were a good source of total polyphenols and flavonoids. Ethanolic extracts from leaves and flowers displayed the highest inhibitory activity against acetylcholinesterase and butyrylcholinesterase, showing potential properties against Alzheimer's disease. Antimicrobial assay showed that leaves and flowers extracts were active against all Gram-positive bacteria tested. The ethanolic leaves extract appeared to have the strongest antibacterial activity against Bacillus cereus with MIC value of 312.5 μg/mL followed by Listeria monocytogenes and Staphylococcus aureus that also exhibited good sensitivity with MIC values of 1250 μg/mL. Moreover, all the extracts possessed anti-HIV activity. The ethanolic flower extract was the most potent inhibitor of HIV-1 RT DNA polymerase RNA-dependent and Ribonuclease H with IC50 values of 0.26 and 0.33 μg/mL, respectively. The LC-DAD metabolic profile showed that ethanolic leaves extract contains high levels of quercetin derivatives. This study suggests that Euphorbia characias extracts represent a good source of natural bioactive compounds which could be useful for pharmaceutical application as well as in food system for the prevention of the growth of food-borne bacteria and to extend the shelf-life of processed foods. PMID:27314007

  3. Biological activity of polyethylene wear debris produced in the patellofemoral joint.

    PubMed

    Ellison, Peter; Tipper, Joanne L; Jennings, Louise M; Fisher, John

    2012-05-01

    Polyethylene wear is considered a threat to the long-term survival of total knee replacements. The aim of this study was to investigate the contribution that resurfacing the patella makes to wear debris-induced osteolysis following total knee replacement. Ultra-high molecular-weight polyethylene wear particles were isolated from simulator lubricant. Particle shape, size, and volume distributions were recorded allowing the osteolytic potential of the wear debris produced in the patellofemoral joint to be estimated using the concept of specific biological activity and functional biological activity. Values were compared with those reported for the tibiofemoral joint. Specific biological activity for the patellofemoral joint was not significantly different from the values for the tibiofemoral joint of total knee replacement devices, and therefore, has a similar potential to stimulate osteolytic cytokine release from macrophages. Functional biological activity was significantly lower for the patellofemoral joint compared with the tibiofemoral joint. Functional biological activity was significantly lower for the patellofemoral joint compared with the fixed bearing and rotating platform total knee replacement devices. However, as patellar resurfacing is commonly fitted as part of a total knee replacement system, this results in a 20% increase in overall functional biological activity for the system. Therefore, implanting a patellar resurfacing will increase the potential for osteolysis in the knee. PMID:22720390

  4. Biologic therapy improves psoriasis by decreasing the activity of monocytes and neutrophils.

    PubMed

    Yamanaka, Keiichi; Umezawa, Yoshinori; Yamagiwa, Akisa; Saeki, Hidehisa; Kondo, Makoto; Gabazza, Esteban C; Nakagawa, Hidemi; Mizutani, Hitoshi

    2014-08-01

    Therapy with monoclonal antibodies to tumor necrosis factor (TNF)-α and the interleukin (IL)-12/23 p40 subunit has significantly improved the clinical outcome of patients with psoriasis. These antibodies inhibit the effects of the target cytokines and thus the major concern during their use is the induction of excessive immunosuppression. Recent studies evaluating the long-term efficacy and safety of biologic therapy in psoriasis have shown no significant appearance of serious adverse effects including infections and malignancies. However, the immunological consequence and the mechanism by which the blockade of a single cytokine by biologics can successfully control the activity of psoriasis remain unclear. In the current study, we investigated the effect of biologic therapy on cytokine production of various lymphocytes and on the activity of monocytes and neutrophils in psoriatic patients. Neutrophils, monocytes and T cells were purified from heparinized peripheral venous blood by Ficoll density gradient centrifugation, and γ-interferon, TNF-α and IL-17 production from lymphocytes was measured by flow cytometer. The activation maker of neutrophils and the activated subsets of monocytes were also analyzed. Biologic therapy induced no significant changes in the cytokine production by lymphocytes from the skin and gut-homing T cells. However, neutrophil activity and the ratio of activated monocyte population increased in severely psoriatic patients were normalized in psoriatic patients receiving biologic therapy. The present study showed that biologic therapy ameliorates clinical symptoms and controls the immune response in patients with psoriasis. PMID:25099154

  5. Biological activities and chemical composition of lichens from Serbia

    PubMed Central

    Kosanic, Marijana; Rankovic, Branislav; Stanojkovic, Tatjana; Vasiljevic, Perica; Manojlovic, Nedeljko

    2014-01-01

    The aim of this study is to investigate chemical composition of acetone extracts of the lichens Parmelia arseneana and Acarospora fuscata and in vitro antioxidant, antimicrobial, and anticancer activities of these extracts and gyrophoric acid isolated from A. fuscata. The HPLC-UV method was used for the identification of secondary metabolites. Stictic acid, norstictic acid, gyrophoric acid, usnic acid, atranorin and chloroatranorin were identified in the A. fuscata. In P. arseneana, we detected stictic acid, norstictic acid, usnic acid and atranorin, while gyrophoric acid was not identified. Antioxidant activity was evaluated by measuring the scavenging capacity of tested samples on DPPH and superoxide anion radicals, reducing the power of samples and determination of total phenolic compounds in extracts. As a result of the study, gyrophoric acid was found to have the largest DPPH radical scavenging activity with an IC50 value of 105.75 µg/ml. Moreover, the tested samples had an effective superoxide anion radical scavenging and reducing power. The total content of phenol in extracts was determined as pyrocatechol equivalent. The antimicrobial activity was estimated by determination of the minimal inhibitory concentration by the broth microdilution method. The most active was also gyrophoric acid, with minimum inhibitory concentration values ranging from 0.019 to 1.25 mg/ml. Anticancer activity was tested against LS174 (human colon carcinoma cell line), A549 (human lung carcinoma cell line), Fem-x (malignant melanoma cell line), and a chronic myelogeneous leukaemia K562 cell line using the MTT method. Extract of P. arseneana expressed the strongest anticancer activity against all cell lines with IC50 values ranging from 11.61 to 47.06 µg/ml. PMID:26417336

  6. Smart interactive electronic system for monitoring the electromagnetic activities of biological systems

    NASA Astrophysics Data System (ADS)

    Popa, Sorin G.; Shahinpoor, Mohsen

    2001-08-01

    A novel electronic device capable of sensing and monitoring the myoelectric, polarization wave and electromagnetic activities of the biological systems and in particular the human body is presented. It is known that all the physical and chemical processes within biological systems are associated with polarization, depolarization waves from the brain, neural signals and myoelectric processes that manifest themselves in ionic and dipole motion. The technology developed in our laboratory is based on certain charge motion sensitive electronics. The electronic system developed is capable of sensing the electromagnetic activities of biological systems. The information obtained is then processed by specialized software in order to interpret it from physical and chemical point of view.

  7. Biological activity of BO-1236, a new antipseudomonal cephalosporin.

    PubMed Central

    Nakagawa, S; Sanada, M; Matsuda, K; Hazumi, N; Tanaka, N

    1987-01-01

    BO-1236, a new cephalosporin having an N-methyl-5,6-dihydroxyisoindolinium moiety on the 3-methylene of the cephem, showed potent activity against gram-negative organisms, including Pseudomonas aeruginosa. The in vitro activity of BO-1236 was superior or comparable to that of ceftazidime, cefotaxime, and cefoperazone in susceptibility tests with clinical isolates. BO-1236 was significantly more active than ceftazidime against P. aeruginosa strains susceptible or resistant to ceftazidime or gentamicin or both. MBCs were usually close to MICs, both of which were influenced by inoculum size to about the same degree as those of the other beta-lactams. BO-1236 was stable to all types of beta-lactamases except type I oxyiminocephalosporin-hydrolyzing enzyme, by which BO-1236 was slightly hydrolyzed. BO-1236 showed protective activity superior to that of ceftazidime and cefotaxime in experimental infections in mice caused by two strains of P. aeruginosa and showed activity comparable to that of ceftazidime and cefotaxime against other gram-negative bacterial infections. PMID:3116919

  8. Synthesis and biological activities of some benzimidazolone derivatives.

    PubMed

    Karale, B K; Rindhe, S S; Rode, M A

    2015-01-01

    The reaction of 5-nitrobenzimidazolone with phenoxyethyl bromide in presence of potassium carbonate in dimethyl formamide obtained 6-nitro-1,3-bis(2-phenoxyethyl)-1,3-dihydro-2H-benzimidazol-2-one. It was reduced using stannous chloride to get 6-amino -1,3-bis(2-phenoxyethyl)-1, 3-dihydro-2H-benzimidazol -2-one, which was further treated with aromatic sulphonyl chloride to obtain benzimidazolone derivatives, 6a-k. These compounds were tested for antibacterial, antituberculosis and antifungal activity. Most of them have shown very good activity against some gram positive and gram negative microorganisms and fungal strains. Some of them have shown moderate activity against Mycobacterium tuberculosis. PMID:26009659

  9. [Biological activity of native and modified lipopolysaccharides of Pragia fontium].

    PubMed

    Varbanets', L D; Shubchyns'kyĭ, V V; Pokhyl, S I; Seĭfullina, I I; Shmatkova, N V; Samburs'kyĭ, S E

    2009-01-01

    Modified lipopolysaccharides (LPS) of Pragia fontium were obtained with germanium complexes (IV) of 2-aminobenzoylhydrazon of salicylic aldehyde (2-NH2-H2Bs), 2-hydroxybenzoylhydrazon salicylic aldehyde (2-OH-H2Bs) and nicotinoylhydrazon of salicylic aldehyde (H2Ns). The modification of LPS was confirmed by IR spectroscopy. Comparative investigations of pyrogenic activity of native and modified LPS showed, that only P. fontium 20125 LPS, modified by germanium complexes with 2-hydroxybenzoylhydrazon of salicylic aldehyde (2-OH-H2Bs) has lost the pyrogenic activity. In the homological reactions of double immunodiffusion in agar it was shown that all modified LPS unlike the native ones lose completely antigenic activity. PMID:19877414

  10. Investigation of some biologic activities of Swertia longifolia Boiss

    PubMed Central

    Hajimehdipoor, H.; Esmaeili, S.; Shekarchi, M.; Emrarian, T.; Naghibi, F.

    2013-01-01

    Swertia species are widespread in Eastern and Southern Asian countries and used in traditional medicine as anti-pyretic, analgesic, gastro and liver tonic. Among different species, only Swertia longifolia grows in Iran. In this investigation, antioxidant, cytotoxic and acetylcholinesterase inhibitory activities of S. longifolia have been studied. Aerial parts and roots of the plant were collected, dried and extracted with methanol 80% (total extract). Different extracts of the plant were obtained using hexane, chloroform, ethyl acetate, methanol, methanol:water (1:1) and water, respectively. Cytotoxic activity was determined by MTT assay on MDBK, HepG2, MCF7, HT29 and A549 cell lines. Antioxidant activity was measured by 2,2-diphenyl-1-picryl hydrazyl (DPPH) free radicals and acetylcholinesterase inhibitory (AChEI) effect was evaluated based on Ellman’s method in 96-well microplates.The results showed no cytotoxicity of the plant extracts on MDBK, HepG2, MCF7, HT29 and A549 cell lines up to 100 μg/ml. All samples showed radical scavenging activity but methanol extract of aerial parts and ethyl acetate extract of the roots showed the highest effects.Total extract of the roots showed higher AChEI activity than the aerial parts. Among different extracts, chloroform and ethyl acetate extracts of the roots and chloroform and methanol:water extracts of the aerial parts were more potent in AChEI assay. It is concluded that aerial parts and roots of the plant are rich in antioxidant agents with no cytotoxicity on selected cell lines up to 100 μg/ml. Moreover, since antioxidant and AChEI activity of compounds play an important role in the treatment of Alzheimer’s disorder, this plant might be a potential candidate for isolation of antioxidant and AChEI compounds which could be used as supportive treatment of Alzheimer’s disease. PMID:24082894

  11. Synthesis and biological activity of nifuroxazide and analogs. II.

    PubMed

    Tavares, L C; Chisté, J J; Santos, M G; Penna, T C

    1999-09-01

    Nifuroxazyde and six analogs were synthesized by varying the substitute from the para-position of the benzenic ring and the heteroatom of the heterocyclic ring. The MIC of seven resultant compounds was determined by serial dilutions, testing the ATCC 25923 strain of Staphylococcus aureus. A significant increase in the anti-microbial activity of thyophenic analogs, as compared with furanic and pyrrholic analogs, was observed. In addition, unlike the cyano and hydroxyl groups, the acetyl group promoted anti-microbial activity. PMID:10622109

  12. Detection and Investigation of Soil Biological Activity against Meloidogyne incognita

    PubMed Central

    Bent, E.; Loffredo, A.; McKenry, M. V.; Becker, J. O.; Borneman, J.

    2008-01-01

    Greenhouse experiments with two susceptible hosts of Meloidogyne incognita, a dwarf tomato and wheat, led to the identification of a soil in which the root-knot nematode population was reduced 5- to 16-fold compared to identical but pasteurized soil two months after infestation with 280 M. incognita J2/100 cm3 soil. This suppressive soil was subjected to various temperature, fumigation and dilution treatments, planted with tomato, and infested with 1,000 eggs of M. incognita/100 cm3 soil. Eight weeks after nematode infestation, distinct differences in nematode population densities were observed among the soil treatments, suggesting the suppressiveness had a biological nature. A fungal rRNA gene analysis (OFRG) performed on M. incognita egg masses collected at the end of the greenhouse experiments identified 11 fungal phylotypes, several of which exhibited associations with one or more of the nematode population density measurements (egg masses, eggs or J2). The phylotype containing rRNA genes with high sequence identity to Pochonia chlamydosporia exhibited the strongest negative associations. The negative correlation between the densities of the P. chlamydosporia genes and the nematodes was corroborated by an analysis using a P. chlamydosporia-selective qPCR assay. PMID:19259527

  13. Withanolides: Biologically Active Constituents in the Treatment of Alzheimer's Disease.

    PubMed

    Khan, Shahid A; Khan, Sher B; Shah, Zarbad; Asiri, Abdullah M

    2016-01-01

    The use of natural products in drug discovery and development have an important history. Several therapeutic agents have been investigated during the biological screenings of natural compounds. It is well documented that plants are possibly the core of novel substances that led to the discovery of new, novel, and effective therapeutic agents. Therefore, in the last few decades, scientists were thoroughly attempting for the search of benevolent drugs to protect mankind from various diseases and discomforts. The diverse chemical structures of natural products are the key element of their success in modern drug discovery. Cholinesterase enzyme inhibitors (ChEI) are chemicals which inhibit the splitting of cholinesterase enzymes (acetylcholinesterase and butyrylcholinesterase). Acetyl cholinesterase (AChE) and butyrylcholinesterase (BChE) are two types of cholinesterase enzymes that have been identified in vertebrates that are responsible for Alzheimer's disease and related dementia. Withanolides are affective plant secondary metabolites which inhibit acetylcholinesterase and butyrylcholinesterase enzyme and thus possibly will be the future drug for Alzheimer's disease. By viewing the importance of natural products in drug discovery and development, we present here, the importance of withanolides in the treatment of Alzheimer's disease. In this article, we also describe the classification and structural characterization of withanolides. This review comprises of 114 compounds. PMID:26527154

  14. Biological activities of extracts from cultivated Granadilla Passiflora alata

    PubMed Central

    Vasic, Sava M.; Stefanovic, Olgica D.; Licina, Braho Z.; Radojevic, Ivana D.; Comic, Ljiljana R.

    2012-01-01

    Research conducted in this study showed the influence of ethanol, acetone and ethyl acetate extracts of the outgrowth of cultivated Passiflora alata on microorganisms, as well as the antioxidant activity and the concentrations of total phenols, flavonoids and tannins. In vitro antimicrobial activities of extracts were studied on 27 species of microorganisms, of which 17 species of bacteria and 10 species of fungi. The strongest antimicrobial activity was detected on G+ bacteria while the activities on other species were moderate. Ethyl acetate extract showed the strongest effect. The concentrations of total phenols were examined by using Folin-Ciocalteu reagent and the obtained values ranged from 14.04 to 34.22 mg GA/g. By using aluminium chloride method, the concentrations of flavonoids were obtained and the values ranged from 33.19 to 62.30 mg RU/g. In determining the amount of tannins we used the method with buthanol-HCl reagent and the obtained value was 5.1 % of dry matter. The efficiency of antioxidation, which we identified through the reduction of DPPH, was in the range from 808.69 to 1107.79 µg/ml for a particular IC50, and AAI values were between 0.07 and 0.10. The best parameters were shown by ethanol extract. All data were statistically analyzed. Overall, extracts showed potential for further investigation and use. PMID:27385958

  15. Total Chemical Synthesis of Biologically Active Vascular Endothelial Growth Factor

    SciTech Connect

    Mandal, Kalyaneswar; Kent, Stephen B.H.

    2011-09-15

    The 204-residue covalent-dimer vascular endothelial growth factor (VEGF, see picture) with full mitogenic activity was prepared from three unprotected peptide segments by one-pot native chemical ligations. The covalent structure of the synthetic VEGF was confirmed by precise mass measurement, and the three-dimensional structure of the synthetic protein was determined by high-resolution X-ray crystallography.

  16. Biological activity of Schinus molle on Triatoma infestans.

    PubMed

    Ferrero, A A; Werdin González, J O; Sánchez Chopa, C

    2006-07-01

    Hexanic extracts from leaves and fruits of Schinus molle were tested for repellent and insecticidal properties against first instar nymphs and eggs of Triatoma infestans, the vector of Chagas' disease. Leaf and fruit extracts were highly repellent for first nymphs. Fruit extracts had also ovicidal activity. PMID:16725281

  17. Activated Sludge. Instructor's Guide. Biological Treatment Process Control.

    ERIC Educational Resources Information Center

    Boe, Owen K.

    This instructor's guide contains the materials needed to teach a seven-lesson unit on activated sludge. These materials include an overview of the unit, lesson plans, lecture outlines (keyed to slides designed for use with the lessons), student worksheets for each of the seven lessons (with answers), and two copies of a final quiz (with and…

  18. Synthesis and biological activity of salinomycin conjugates with floxuridine.

    PubMed

    Huczyński, Adam; Antoszczak, Michał; Kleczewska, Natalia; Lewandowska, Marta; Maj, Ewa; Stefańska, Joanna; Wietrzyk, Joanna; Janczak, Jan; Celewicz, Lech

    2015-03-26

    As part of our program to develop anticancer agents, we have synthesized new compounds, which are conjugates between well-known anticancer drug, floxuridine and salinomycin which is able to selectivity kill cancer stem cells. The conjugates were obtained in two ways i.e. by copper(I) catalysed click Huisgen cycloaddition reaction performed between 3'-azido-2',3'-dideoxy-5-fluorouridine and salinomycin propargyl amide, and by the ester synthesis starting from salinomycin and floxuridine under mild condition. The compounds obtained were characterized by spectroscopic methods and evaluated for their in vitro cytotoxicity against seven human cancer cell lines as well as antibacterial activity against clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA) and Staphylococcus epidermidis (MRSE). The conjugate obtained by esterification reaction showed a significantly higher antiproliferative activity against the drug-resistant cancer cells and lower toxicity than those of salinomycin and floxuridine towards normal cells, as well as standard anticancer drugs, such as cisplatin and doxorubicin. The conjugate compound revealed also moderate activity against MRSA and MRSE bacterial strains. Very high activity of floxuridine and 5-fluorouracil against MRSA and MRSE has been also observed. PMID:25644674

  19. Marine Biology Field Trip Sites. Ocean Related Curriculum Activities.

    ERIC Educational Resources Information Center

    Pauls, John

    The ocean affects all of our lives. Therefore, awareness of and information about the interconnections between humans and oceans are prerequisites to making sound decisions for the future. Project ORCA (Ocean Related Curriculum Activities) has developed interdisciplinary curriculum materials designed to meet the needs of students and teachers…

  20. Synthesis and biological activity of substituted-4,5,6,7-tetrahydrothieno pyridines: a review.

    PubMed

    Sangshetti, Jaiprakash N; Zambare, Abhay S; Khan, Firoz A Kalam; Gonjari, Indrajeet; Zaheer, Zahid

    2014-01-01

    4,5,6,7-Tetrahydrothieno pyridine is an important class of heterocyclic nucleus. Various 4,5,6,7-tetrahydrothieno pyridine derivatives have been synthesized and evaluated for various biological activities in different models with desired findings. Some analogs have shown potent biological activities and may be considered as lead molecule for the development of future drugs. Number of drug molecules are available in the market and many molecules are in clinical development containing 4,5,6,7-tetrahydrothieno pyridine nucleus as an important core. This review is an attempt to organize the chemical and biological aspects of 4,5,6,7-tetrahydrothieno pyridine analogs reported in last 20 year to till date. Review mainly focuses on the important role of the core in synthesis of drug or drug intermediates giving emphasis on synthetic schemes and biological activities of the different 4,5,6,7-tetrahydrothieno pyridine analogs. PMID:25373848

  1. Flavopiridol: pleiotropic biological effects enhance its anti-cancer activity.

    PubMed

    Newcomb, Elizabeth W

    2004-06-01

    Flavopiridol has potent anti-proliferative properties due to its direct action of binding to the ATP-binding pocket of cyclin-dependent kinases (cdks), and due to its indirect action reducing levels of other cyclins and cdk inhibitors, contributing to its pleiotropic effects. Flavopiridol is a potent apoptotic agent due to its ability to cause cell death in cycling as well as non-cycling tumor cells; to down-regulate important cell survival proteins, such as survivin, through inhibition of the phosphorylation of Thr34; to increase sensitivity for S phase cells to drug treatment by modulating E2F-1 transcription factor activity in tumor cells; to induce both caspase-dependent and -independent mitochondrial cell death pathways; and to inhibit the activation of p-Akt which in turn inhibits activation of NF-kappaB. Flavopiridol possesses several important anti-angiogenic activities including induction of apoptosis of endothelial cells; inhibition of the hypoxic induction of vascular endothelial growth factor and/or its production under hypoxic conditions through inhibition of HIF-1alpha transcription; and decreased secretion of matrix metalloproteinases that is linked with significant inhibition of invasive potential in Matrigel assays. Taken together, the anti-proliferative and anti-angiogenic properties of flavopiridol may contribute to its anti-tumor activities observed in several preclinical animal models of human cancers including prostate, lymphoid, head and neck, colon, and glioma. These promising preclinical observations opened the way for phase I and II clinical trials. Given the low toxicity profile of flavopiridol used as a single agent in patients, combination therapy now offers numerous opportunities in the near future to improve the efficacy of flavopiridol in the treatment of refractory cancers. PMID:15166614

  2. Biological activities of two macroalgae from Adriatic coast of Montenegro.

    PubMed

    Kosanić, Marijana; Ranković, Branislav; Stanojković, Tatjana

    2015-07-01

    In the present investigation the acetone extracts of macroalgae Ulva lactuca and Enteromorpha intestinalis were tested for antioxidant, antimicrobial and cytotoxic potential. Antioxidant activity was evaluated by measuring the scavenging capacity of tested samples on DPPH and superoxide anion radicals, reducing the power of samples and determination of total phenolic and flavonoid compounds in extracts. As a result of the study, U. lactuca extract was found to have a better free radical scavenging activity (IC50 = 623.58 μg/ml) than E. intestinalis extract (IC50 = 732.12 μg/ml). Moreover, the tested extracts had effective ferric reducing power and superoxide anion radical scavenging. The total content of phenol in extracts of U. lactuca and E. intestinalis was 58.15 and 40.68 μg PE/mg, while concentrations of flavonoids were 39.58 and 21.74 μg RE/mg, respectively. Furthermore, among the tested species, extracts of U. lactuca showed a better antimicrobial activity with minimum inhibitory concentration values ranging from 0.156 to 5 mg/ml, but it was relatively weak in comparison with standard antibiotics. Bacillus mycoides and Bacillus subtilis were the most susceptible to the tested extracts. Contrary to this Aspergillus flavus, Aspergillus fumigatus and Penicillium purpurescens were the most resistant. Finally, cytotoxic activity of tested extracts was evaluated on four human cancer cell lines. Extract of E. intestinalis expressed the stronger cytotoxic activity towards all tested cell lines with IC50 values ranging from 74.73 to 155.39 μg/ml. PMID:26150743

  3. [Effects of biologically-active dietary supplement from marine biology on cholinesterase activity and blood lipid peroxidation in humans].

    PubMed

    Romanenko, V A; Kovalev, N N; Enikeeva, N A; Epshteĭn, L M

    2000-01-01

    Influence of dietary supplement Tinrostim-C on cholinesterase (ChE) activity and serum lipids peroxidation (LP) in patients whose work connects with emotional stress was examined. Activity of ChE was measured by Ellman calorimetric method (with acetylthiocholin as substrate), LP--by fluorimetric method with malone dialdehyde. Tinrostim-C was given three times a day in 0.5 g. On the 10th day of taking the preparation an activity of serum ChE increased 23.5% higher and had been staying higher during the whole period of observation. In vitro experiments showed an activating effect of Tinrostim-C and piracetam for serum ChE. The level of LP being initially higher was decreasing to values close to normal and had been staying at decreased level during the whole period of observation. PMID:11247159

  4. Biologically Inspired Photocatalytically Active Membranes for Water Treatment

    NASA Astrophysics Data System (ADS)

    Kinsinger, Nichola M.

    There is an alarming increase of a variety of new chemicals that are now being discharged into the wastewater system causing increased concern for public health and safety because many are not removed by typical wastewater treatment practices. Titanium Dioxide (TiO2) is a heterogeneous photocatalytic material that rapidly and completely mineralizing organics without harmful byproducts. TiO2 is synthesized by various methods, which lack the necessary control of crystal size, phase, and morphological features that yield optimized semiconductor materials. Mineralizing organisms demonstrate how nature can produce elegant structures at room temperature through controlled organic-mineral interactions. Here, we utilize biologically-inspired scaffolds to template the nucleation and growth of inorganic materials such as TiO2, which aid in controlling the size and phase of these particles and ultimately, their properties. Nanosized rutile and anatase particles were synthesized under solution conditions at relatively low temperatures and mild pH conditions. The effects of reaction conditions on phase and grain size were investigated and discussed from coordination chemistry and coarsening mechanisms. Photocatalytic characterization of TiO2 phase mixtures was performed to investigate their synergistic effect. The suspension conditions of these catalytic nanomaterials were modulated to optimize the degradation rate of organic analytes. Through the addition of an organic scaffold during the synthesis reaction, a mechanically robust (elastic) composite material containing TiO2 nanoparticles was produced. This composite was subsequently heat-treated to produce a porous, high surface area TiO2 nanoparticulate membrane. Processing conditions were investigated to characterize the growth and phase transformation of TiO2, which ultimately impacts photocatalytic performance. These bulk porous TiO2 structures can be fabricated and tailored to act as stand-alone photocatalytic membranes

  5. Synthesis and biological activity of Wuweizisu C and analogs.

    PubMed

    Chang, J B; Wang, Q; Li, Y F

    2009-01-01

    Lignans are widely distributed in nature. The earliest recorded medicinal use of lignans dated back to over 1000 years ago. Lignan-rich plant products were also active ingredients in Chinese and Japanese folk medicines for the treatment of various diseases. The dried root and stem of this plant are listed in the Chinese pharmacopoeia for the treatment of rheumatoid arthritis, gastric, duodenal ulcers and many other diseases. This review highlights synthetic strategies for the Wuweizisu C analogs and the important pharmacological activities as well as therapeutic findings related to the treatment of HBV and other diseases. Notably a significant and ongoing project on Wuweizisu C and its analogs has led to the discovery and development of two potent derivatives alpha-DDB and BICYCLOL which are currently in clinical trials against HBV, especially in lowering elevated SGPT levels. Further design, synthesis, and evaluation of Wuweizisu C analogs are discussed. PMID:19903156

  6. [Biological activity of selenorganic compounds at heavy metal salts intoxication].

    PubMed

    Rusetskaya, N Y; Borodulin, V B

    2015-01-01

    Possible mechanisms of the antitoxic action of organoselenium compounds in heavy metal poisoning have been considered. Heavy metal toxicity associated with intensification of free radical oxidation, suppression of the antioxidant system, damage to macromolecules, mitochondria and the genetic material can cause apoptotic cell death or the development of carcinogenesis. Organic selenium compounds are effective antioxidants during heavy metal poisoning; they exhibit higher bioavailability in mammals than inorganic ones and they are able to activate antioxidant defense, bind heavy metal ions and reactive oxygen species formed during metal-induced oxidative stress. One of promising organoselenium compounds is diacetophenonyl selenide (DAPS-25), which is characterized by antioxidant and antitoxic activity, under conditions including heavy metal intoxication. PMID:26350735

  7. Biologically Active Cannabinoids from High-Potency Cannabis sativa

    PubMed Central

    Radwan, Mohamed M.; ElSohly, Mahmoud A.; Slade, Desmond; Ahmed, Safwat A.; Khan, Ikhlas A.; Ross, Samir A.

    2016-01-01

    Nine new cannabinoids (1–9) were isolated from a high-potency variety of Cannabis sativa. Their structures were identified as (±)-4-acetoxycannabichromene (1), (±)-3″-hydroxy-Δ(4″,5″)-cannabichromene (2), (−)-7-hydroxycannabichromane (3), (−)-7R-cannabicoumarononic acid A (4), 5-acetyl-4-hydroxycannabigerol (5), 4-acetoxy-2-geranyl-5-hydroxy-3-n-pentylphenol (6), 8-hydroxycannabinol (7), 8-hydroxycannabinolic acid A (8), and 2-geranyl-5-hydroxy-3-n-pentyl-1,4-benzoquinone (9) through 1D and 2D NMR spectroscopy, GC-MS, and HRESIMS. The known sterol β-sitosterol-3-O-β-d-glucopyranosyl-6′-acetate was isolated for the first time from cannabis. Compounds 6 and 7 displayed significant antibacterial and antifungal activities, respectively, while 5 displayed strong antileishmanial activity. PMID:19344127

  8. Purification, characterization and biological activities of a garlic oligosaccharide.

    PubMed

    Tsukamoto, Sadaji; Okamoto, Kouji; Inanaga, Junji; Karasaki, Yuji

    2008-06-01

    A novel oligosaccharide was purified from garlic (Allium sativum L.) bulbs via hot water extraction, ammonium sulfate precipitation, gel filtration and ion exchange chromatography. The molecular weight of the oligosaccharide was determined to be 1800. A nuclear magnetic resonance (NMR) study showed that ten fructose molecules were connected by beta1-2 linkage to a terminal glucose. The oligosaccharide had cytotoxic activities against human malignant lymphoma cells (U937) and colon adenocarcinoma cells (WiDr) in vitro. Furthermore, this oligosaccharide significantly suppressed the growth of murine colon adenocarcinoma cells (colon 26) in vivo. The oligosaccharide also stimulated interferon-gamma production by human peripheral blood lymphocyte in vitro, indicating that it may activate the immunological pathways and suppress the growth of tumors in vivo. PMID:18655544

  9. Biologically active flavonoids and terpenoids from Egletes viscosa.

    PubMed

    Lima, M A; Silveira, E R; Marques, M S; Santos, R H; Gambardela, M T

    1996-01-01

    The steam volatile components from the hexane extract of dried flower buds of Egletes viscosa were identified by gas chromatography-mass spectrometry as trans-carvyl acetate, cis-carvyl acetate, sabinyl acetate, verbenyl acetate, cyclopentaethylidene, geranyl acetate and 5-methylfuranone, and trans-pinocarvyl acetate (major component). From the non-volatile residue, centipedic acid and a novel clerodane diterpene, 12-acetoxy-hawtriwaic acid lactone, were isolated. From the ethanol extract, ternatin (4',5-dihidroxy-3,3',7,8-tetramethoxyflavone), was isolated. Ternatin showed anti-inflammatory, hepatoprotection and gastroprotection properties, and, according to the NCI protocols, it showed moderate activity against HIV. The diterpenes showed antispasmodic activity. Structure determination of these secondary metabolites was accomplished by spectrometric methods, including 2D NMR, chemical interconversion and X-ray crystallographic analysis. PMID:8588867

  10. Persistence of biologically active compounds in soil: Final report

    SciTech Connect

    Williams, S.E.

    1987-02-01

    This document describes the long-term effects of soil-applied oil shale process water on the VA fungi and Rhizobium bacteria in a native soil. Techniques include assessing the VA fungal activity at field treatment plots and using treated field soils in a bioassay to determine VA infection and Rhizobium-nodulation potentials four years after process water application. 52 refs., 32 figs., 2 tabs.

  11. Biological activity assessment of a novel contraceptive antimicrobial agent.

    PubMed

    Garg, A; Anderson, R A; Zaneveld, L J D; Garg, S

    2005-01-01

    Microbicides are a new category of compounds being developed as a prophylactic approach for the prevention of transmission of sexually transmitted diseases (STDs), including the human immunodeficiency virus (HIV). These are primarily being developed as women-controlled methods, with the target of designing new compounds or formulations that can be used without the knowledge of a male partner. Microbicide screening can be initially based on their hyaluronidase-inhibiting (HI) activity, as this enzyme plays a major role in the sperm and microbe penetration into the substrate. Derivatives of hesperidin, a citrus flavonoid glycoside, have been reported in the literature for their HI effects. Hesperidin was thereby sulphonated under strictly controlled conditions and the active fraction isolated and characterized, based on its HI activity. This derivative was screened for antimicrobial and enzyme-inhibitory activities, specifically for the reproductive tract. Sulphonated hesperidin (SH) was found to completely inhibit the sperm enzymes hyaluronidase, giving an indication toward its contraceptive effects. It was also been found to inhibit various sexually transmitted pathogens, including Chlamydia trachomatis, Neisseria gonorrhoea, HIV, and Herpes Simplex virus type 2 (HSV-2). Its safety assessment was based on its noninterference in sperm motility and its penetration through the cervical mucus, and no effect on the growth of lactobacilli, the normal vaginal flora. It was also found to be nontoxic to the HIV substrate cells (MT2 cells). The study concludes that sulphonated hesperidin can be developed as a potential microbicide for a dual prophylaxis of contraception and transmission of STDs and AIDS. PMID:15867010

  12. Copper complexes of glycyl-histidyl-lysine and two of its synthetic analogues: chemical behaviour and biological activity.

    PubMed

    Conato, C; Gavioli, R; Guerrini, R; Kozlowski, H; Mlynarz, P; Pasti, C; Pulidori, F; Remelli, M

    2001-05-01

    Copper complex formation equilibria of glycyl-L-histidyl-L-lysine (Gly-His-Lys, GHK) and of two synthetic analogues, where the histidine residue was replaced with a synthetic amino acid (L-spinacine or L-1,2,3,4-tetrahydro-isoquinoline-3-carboxylic acid), have been carefully investigated using different experimental techniques: potentiometry, solution calorimetry, UV-VIS spectrophotometry, circular dichroism and electron paramagnetic resonance spectroscopies. All the ligands formed complexes having different stoichiometries and stabilities; evidence for the formation of binuclear species is also shown. The structures of the main complexes are discussed. It is suggested that the lateral lysine amino group participates in complex formation, but only at alkaline pH values: at physiological pH this group is protonated and available for possible interactions with cellular receptors. The above tripeptides have been tested for their enzymatic stability in human serum: the synthetic compounds showed no significant degradation for at least 3 h. Finally, their activity as growth factor has been studied in vitro. The two synthetic analogues showed an activity comparable to or even higher than that of GHK, thus suggesting their possible use as additives in cell culture media, even in the presence of serum. Relevant information on the GHK action mechanism as cell growth factor has been obtained: the formation of copper complexes, driven by the first (Gly) residue, appears necessary while the second residue (His) does not appear to play a specific role; the presence of the free side chain of the third residue (Lys) appears to be of fundamental importance. PMID:11325542

  13. Biological activity of phenylpropionic acid isolated from a terrestrial Streptomycetes.

    PubMed

    Narayana, Kolla J P; Prabhakar, Peddikotla; Vijayalakshmi, Muvva; Venkateswarlu, Yenamandra; Krishna, Palakodety S J

    2007-01-01

    The strain ANU 6277 was isolated from laterite soil and identified as Streptomyces sp. closely related to Streptomyces albidoflavus cluster by 16S rRNA analysis. The cultural, morphological and physiological characters of the strain were recorded. The strain exhibited resistance to chloramphenicol, penicillin and streptomycin. It had the ability to produce enzymes such as amylase and chitinase. A bioactive compound was isolated from the strain at stationary phase of culture and identified as 3-phenylpropionic acid (3-PPA) by FT-IR, EI-MS, 1H NMR and 13C NMR spectral studies. It exhibited antimicrobial activity against different bacteria like Bacillus cereus, B. subtilis, Escherichia coli, Klebsiella pneumoniae, Proteus vulgaris, Pseudomonas aeruginosa, P. flourescens, Staphylococcus aureus and some fungi including Aspergillus flavus, A. niger, Candida albicans, Fusarium oxysporum, F. udum and Penicillium citrinum. The antifungal activity of 3-PPA of the strain was evaluated in in vivo and in vitro conditions against Fusarium udum causing wilt disease in pigeon pea. The compound 3-PPA is an effective antifungal agent when compared to tricyclozole (fungicide) to control wilt caused by F. udum, but it exhibited less antifungal activity than carbendazim. PMID:18062653

  14. Biological Activity of Vegetal Extracts Containing Phenols on Plant Metabolism.

    PubMed

    Ertani, Andrea; Pizzeghello, Diego; Francioso, Ornella; Tinti, Anna; Nardi, Serenella

    2016-01-01

    The influence of vegetal extracts derived from red grape, blueberry fruits and hawthorn leaves on Zea mays L. plant growth and the activity of phenylalanine ammonia-lyase (PAL), a key enzyme of the phenylpropanoid pathway, was investigated in laboratory experiments. The extracts were characterized using FT-IR and Raman spectroscopies in order to obtain a pattern of the main functional groups. In addition, phenols content was determined by HPLC, whereas the content of indoleacetic acid and isopentenyladenosine hormones was determined by ELISA test and the auxin and gibberellin-like activities by plant-bioassays. The treated maize revealed increased root and leaf biomass, chlorophyll and sugars content with respect to untreated plants. Hawthorn, red grape skin and blueberry at 1.0 mL/L induced high p-coumaric content values, whilst hawthorn also showed high amounts of gallic and p-hydroxybenzoic acids. PAL activity induced by hawthorn at 1.0 mL/L had the highest values (11.1-fold UNT) and was strongly and linearly related with the sum of leaf phenols. Our results suggest that these vegetal extracts contain more than one group of plant-promoting substances. PMID:26867189

  15. Purification, Characterization and Biological Activity of Polysaccharides from Dendrobium officinale.

    PubMed

    Huang, Kaiwei; Li, Yunrong; Tao, Shengchang; Wei, Gang; Huang, Yuechun; Chen, Dongfeng; Wu, Chengfeng

    2016-01-01

    Polysaccharide (DOPA) from the stem of D. officinale, as well as two fractions (DOPA-1 and DOPA-2) of it, were isolated and purified by DEAE cellulose-52 and Sephacryl S-300 chromatography, and their structural characteristics and bioactivities were investigated. The average molecular weights of DOPA-1 and DOPA-2 were 394 kDa and 362 kDa, respectively. They were mainly composed of d-mannose, d-glucose, and had a backbone consisting of 1,4-linked β-d-Manp and 1,4-linked β-d-Glcp with O-acetyl groups. Bioactivity studies indicated that both DOPA and its purified fractions (DOPA-1 and DOPA-2) could activate splenocytes and macrophages. The D. officinale polysaccharides had stimulatory effects on splenocytes, T-lymphocytes and B-lymphocytes, promoting the cell viability and NO production of RAW 264.7 macrophages. Furthermore, DOPA, DOPA-1 and DOPA-2 were found to protect RAW 264.7 macrophages against hydrogen peroxide (H₂O₂)-induced oxidative injury by promoting cell viability, suppressing apoptosis and ameliorating oxidative lesions. These results suggested that D. officinale polysaccharides possessed antioxidant activity and mild immunostimulatory activity. PMID:27248989

  16. Synthesis, characterization and biological activities of Cu(II), Co(II), Mn(II), Fe(II), and UO2(VI) complexes with a new Schiff Base hydrazone: O-hydroxyacetophenone-7-chloro-4-quinoline hydrazone.

    PubMed

    Al-Shaalan, Nora H

    2011-01-01

    The Schiff base hydrazone ligand HL was prepared by the condensation reaction of 7-chloro-4-quinoline with o-hydroxyacetophenone. The ligand behaves either as monobasic bidentate or dibasic tridentate and contain ONN coordination sites. This was accounted for be the presence in the ligand of a phenolic azomethine and imine groups. It reacts with Cu(II), Ni(II), Co(II), Mn(II), UO(2) (VI) and Fe(II) to form either mono- or binuclear complexes. The ligand and its metal complexes were characterized by elemental analyses, IR, NMR, Mass, and UV-Visible spectra. The magnetic moments and electrical conductance of the complexes were also determined. The Co(II), Ni(II) and UO(2) (VI) complexes are mononuclear and coordinated to NO sites of two ligand molecules. The Cu(II) complex has a square-planar geometry distorted towards tetrahedral, the Ni(II) complex is octahedral while the UO(2) (VI) complex has its favoured heptacoordination. The Co(II), Mn(II) complexes and also other Ni(II) and Fe(III) complexes, which were obtained in the presence of Li(OH) as deprotonating agent, are binuclear and coordinated via the NNNO sites of two ligand molecules. All the binuclear complexes have octahedral geometries and their magnetic moments are quite low compared to the calculated value for two metal ions complexes and thus antiferromagnetic interactions between the two adjacent metal ions. The ligand HL and metal complexes were tested against a strain of Gram +ve bacteria (Staphylococcus aureus), Gram -ve bacteria (Escherichia coli), and fungi (Candida albicans). The tested compounds exhibited high antibacterial activities. PMID:21996717

  17. Disposition and anticoagulant activity of biologically active heparin fragments in the rat

    SciTech Connect

    Larsen, A.K.; Hetelekidis, S.; Langer, R.

    1984-11-01

    The disposition of biologically active (/sup 35/S)heparin fragments was studied in both normal and uremic rats after an i.v. dose of 1 mg/kg. In normal animals, the amount of radioactivity in the blood rapidly decreased with a half-life of less than 2 min whereas the anticoagulant activity showed a half-life of 30 min. By 5 hr, only 0.4% of the initial radioactivity was present in the blood whereas no anticoagulant activity could be detected. The heparin fragments were rapidly excreted: by 5 hr, 85% of the initial dose was excreted into the urine, whereas only 1% of the radioactivity was present in the feces. In contrast, 55% of the initial dose of the same amount of radioactive heparin was excreted into the urine after 5 hr. By 5 hr, 5.2% of the heparin fragments was organ-associated and 3.1% was present in the skin, muscle and bone. One week after injection, 3.9% of the radioactivity was still present in the body. In uremic animals, the radioactivity in the blood decreased to 12% of the initial dose by 5 hr whereas 13.5% was organ-associated and 64% was present in the skin, muscle and bone. Comparison of heparin with di- or hexasac-charide fragments indicated that both the clearance in the blood and the excretion into the urine are size-dependent. By 5 hr, the body burden of heparin is approximately five times higher than it is after the same dose of heparin fragments.

  18. Biological activity of photoproducts of merocyanine 540 generated by laser-light activation

    NASA Astrophysics Data System (ADS)

    Gulliya, Kirpal S.; Chanh, Tran C.; Pervaiz, Shazib; Harriman, Anthony; Matthews, James Lester

    1992-08-01

    Controlled exposure of photoactive compounds to light prior to their use in biological targets results in the formation of heretofore unknown photoproducts. This process of photoproduct generation, termed "preactivation," renders the photactive compound capable of systemic use without further dependence on light. Preactivation of mercyanin 540 (MC540) and several other photoactive compounds is achievable by exposure to CW and pulse laser radiation. The singlet oxygen generated at excited states attacks the dye molucule itself, resulting in the formation of biologically active photoproducts. For preactivated MC540 (photoproducts of MC540) generated by exposure to argon laser light (514 nm) and light from free-electron laser, we have demonstrated its effectiveness in selective killing of certain types of cultured tumor cells as well as human immunodeficiency virus type 1 (HIV-1) with very low, if any, damage to normal cells and tisues. For example, approximately 90% of the Burkitt's lymphoma Daudi cells and HL-60 leukemic cells are killed by preactivated MC540 at a concentration of 120 μg/ml. A two-hour treatment of cultured cells with buthionine sulfoxamine followed by the treatement with preactivated MC540 reults in 99.99% inhibition of clonogenic tumor stem cell growth. We also have demonstrated that preactivated MC540 is very effective in killing cell-free and cell-associated HIV-1. It also is very effective in killing HIV-1 and simian immunodeficiency virus (SIV) in virus-infected blood in vitro as determined by reverse transcriptase, P24, P17, core antigen expression and synctium formation. Treatment of HIV-1 with preactivated MC540 renders the treated HIV-1 incapable of binding to CD4 target molecules on T cells as determined by immunofluorescence and radioimmunoprecipitation assays. In vivo toxicology studies show that preactivated MC540 is very well tolerated and does not produce any signs of adverse reaction at the therapeutic doses, as determined by

  19. Manipulating lipid bilayer material properties using biologically active amphipathic molecules

    NASA Astrophysics Data System (ADS)

    Ashrafuzzaman, Md; Lampson, M. A.; Greathouse, D. V.; Koeppe, R. E., II; Andersen, O. S.

    2006-07-01

    Lipid bilayers are elastic bodies with properties that can be manipulated/controlled by the adsorption of amphipathic molecules. The resulting changes in bilayer elasticity have been shown to regulate integral membrane protein function. To further understand the amphiphile-induced modulation of bilayer material properties (thickness, intrinsic monolayer curvature and elastic moduli), we examined how an enantiomeric pair of viral anti-fusion peptides (AFPs)—Z-Gly-D-Phe and Z-Gly-Phe, where Z denotes a benzyloxycarbonyl group, as well as Z-Phe-Tyr and Z-D-Phe-Phe-Gly—alters the function of enantiomeric pairs of gramicidin channels of different lengths in planar bilayers. For both short and long channels, the channel lifetimes and appearance frequencies increase as linear functions of the aqueous AFP concentration, with no apparent effect on the single-channel conductance. These changes in channel function do not depend on the chirality of the channels or the AFPs. At pH 7.0, the relative changes in channel lifetimes do not vary when the channel length is varied, indicating that these compounds exert their effects primarily by causing a positive-going change in the intrinsic monolayer curvature. At pH 4.0, the AFPs are more potent than at pH 7.0 and have greater effects on the shorter channels, indicating that these compounds now change the bilayer elastic moduli. When AFPs of different anti-fusion potencies are compared, the rank order of the anti-fusion activity and the channel-modifying activity is similar, but the relative changes in anti-fusion potency are larger than the changes in channel-modifying activity. We conclude that gramicidin channels are useful as molecular force transducers to probe the influence of small amphiphiles upon lipid bilayer material properties.

  20. Biological Activities and Composition of Ferulago carduchorum Essential Oil

    PubMed Central

    Golfakhrabadi, Fereshteh; Khanavi, Mahnaz; Ostad, Seyed Nasser; Saeidnia, Soodabeh; Vatandoost, Hassan; Abai, Mohammad Reza; Hafizi, Mitra; Yousefbeyk, Fatemeh; Rad, Yaghoob Razzaghi; Baghenegadian, Ameneh; Ardekani, Mohammad Reza Shams

    2015-01-01

    Background: Ferulago carduchorum Boiss and Hausskn belongs to the Apiaceae family. This plant grows in west part of Iran that local people added it to dairy and oil ghee to delay expiration date and give them a pleasant taste. The aim of this study was to investigate the antioxidant, antimicrobial, acetyl cholinesterase inhibition, cytotoxic, larvicidal activities and composition of essential oil of F. carduchorum. Methods: Acetyl cholinesterase (AChE) inhibitory, larvicidal activities and chemical composition of essential oil of F. carduchorum were investigated. Besides, antioxidant, antimicrobial and cytotoxic activities of essential oil were tested using DPPH, microdilution method and MTT assay, respectively. Results: The major components of essential oil were (z)-β-ocimene (43.3%), α-pinene (18.23%) and bornyl acetate (3.98%). Among 43 identified components, monoterpenes were the most compounds (84.63%). The essential oil had noticeable efficiency against Candida albicans (MIC= 2340 μg ml−1) and it was effective against Anopheles stephensi with LC50 and LC90 values of 12.78 and 47.43 ppm, respectively. The essential oil could inhibit AChE (IC50= 23.6 μl ml−1). The essential oil showed high cytotoxicity on T47D, HEP-G2 and HT-29 cell lines (IC50< 2 μg ml−1). Conclusion: The essential oil of F. carduchorum collected from west of Iran had anti-Candida, larvicidal and cytotoxicity effects and should be further investigated in others in vitro and in vivo experimental models. PMID:26114148

  1. Interaction of metallic clusters with biologically active curcumin molecules

    NASA Astrophysics Data System (ADS)

    Gupta, Sanjeev K.; He, Haiying; Liu, Chunhui; Dutta, Ranu; Pandey, Ravindra

    2015-09-01

    We have investigated the interaction of subnano metallic Gd and Au clusters with curcumin, an important biomolecule having pharmacological activity. Gd clusters show different site preference to curcumin and much stronger interaction strength, in support of the successful synthesis of highly stable curcumin-coated Gd nanoparticles as reported recently. It can be attributed to significant charge transfer from the Gd cluster to curcumin together with a relatively strong hybridization of the Gd df-orbitals with curcumin p-orbitals. These results suggest that Gd nanoparticles can effectively be used as delivery carriers for curcumin at the cellular level for therapy and medical imaging applications.

  2. [Biologically Active Peptides Isolated from Dill Anethum graveolens L].

    PubMed

    Kulikova, O G; Maltsev, D I; Ilyina, A P; Burdina, A V; Yamskova, V P; Yamskov, I A

    2015-01-01

    Peptide mixtures with molecular weights of 1000-2000 Da and in vivo membrano-trophic activity against mouse hepatocyte culture at very low concentrations were isolated from dill Anethum graveolens L. leaves. It has been found that plant peptides in aqueous solution formed larger nanosized particles of approximately 90 nm with a secondary structure mainly composed of β-structures and random coil structures. We demonstrated that peptides isolated from A. graveolens in vitro at an ultra-low dosage affected the size of the area of pigmented cells of amphibian liver, which are analogous to Kupffer cells of the mammalian liver, using roller organotypic newt liver culture models. PMID:26204780

  3. New approaches to estimation of peat deposits for production of biologically active compounds

    NASA Astrophysics Data System (ADS)

    Stepchenko, L. M.; Yurchenko, V. I.; Krasnik, V. G.; Syedykh, N. J.

    2009-04-01

    It is known, that biologically active preparations from peat increase animals productivity as well as resistance against stress-factors and have adaptogeneous, antioxidant, immunomodulative properties. Optymal choice of peat deposits for the production of biologically active preparations supposes the detailed comparative analysis of peat properties from different deposits. For this the cadastre of peat of Ukraine is developed in the humic substances laboratory named after prof. Khristeva L.A. (Dnipropetrovsk Agrarian University, Ukraine). It based on the research of its physical and chemical properties, toxicity and biological activity, and called Biocadastre. The Biocadastre is based on the set of parameters, including the descriptions of physical and chemical properties (active acidity, degree of decomposition, botanical composition etc.), toxicity estimation (by parabyotyc, infusorial, inhibitor and other tests), biological activity indexes (growth-promoting, antioxidative, adaptogeneous, immunomodulative antistress and other actions). The blocks of Biocadastre indexes are differentiated, taking into account their use for creation the preparations for vegetable, animals and microorganisms. The Biocadastre will allow to choose the peat deposits, most suitable for the production of different biologically active preparations, both wide directed and narrow spectrum of action, depending on application fields (medicine, agriculture, veterinary medicine, microbiological industry, balneology, cosmetology).

  4. Biological activities of Eremostachys laevigata Bunge. grown in Iran.

    PubMed

    Esmaeili, Akbar

    2012-10-01

    Essential oil from flowers, stems, and roots of Eremostachys laevigata Bunge. gathered in Iran was analyzed using gas chromatography (GC) and gas chromatography/mass spectroscopy (GC/MS), and 23, 21, and 9 compounds were identified, respectively. The primary components of all three oils were found to be 1,8-cineole, benzaldehyde, and piperitenone oxide: 18.3%, 18.7%, and 2.5%; 17.9%, 7.7%, and 63.3%; and 15.7%, 21.3%, and 1.2%, respectively. The oils derived from flowers and stems also contained cis-piperitone oxide as a major component (10.1% and 12.2%, respectively). E. laevigata oil showed antibacterial activity, particularly towards Gram-positive bacteria; additionally antioxidant activity was induced with IC(50) of flowers, stems and roots of E. laevigata (277.1, 495.0, and 212.6 μg/ml), respectively. Furthermore, under β-carotene-linoleic acid test assay the flower, stem, and root oils of E. laevigata had a high antibacterial effect. PMID:23009997

  5. Analytical development of a binuclear oxo-manganese complex bio-inspired on oxidase enzyme for doping control analysis of acetazolamide.

    PubMed

    Machini, Wesley B S; Teixeira, Marcos F S

    2016-05-15

    A bio-inspired electrochemical sensor using a binuclear oxo-manganese complex was evaluated and applied in the detection of a substance associated with doping in sports: acetazolamide (ACTZ). Investigation was made of the influence of different experimental variables on the electrocatalytic oxidation of ACTZ by the bio-inspired sensor, such as pH and interfering species. The bio-inspired sensor showed the best response in the range from 5.00×10(-9) to 7.00×10(-8) mol L(-1) ACTZ, with a linear range from 5.00×10(-9) to 2.50×10(-8) mol L(-1) and a detection limit of 4.76×10(-9) mol L(-1). The sensor exhibited characteristics similar to the Michaelis-Menten model of an enzymatic electrode, due to the use of a multinucleated complex of manganese with μ-oxo units, which was able to mimic the properties of enzymes with manganese as a cofactor in their composition, such as Mn-containing oxidase. The determination of ACTZ with the bio-inspired sensor was evaluated using three different synthetic biological fluids (plasma, saliva, and urine), demonstrating its viability for use with real samples. The analysis of ACTZ in real urine samples using the bio-inspired sensor, simulating the method adopted by the World Anti-Doping Agency, which revealed viable, suggesting a new and promising platform to be used in these analysis. PMID:26745790

  6. Changes in biologically active ultraviolet radiation reaching the Earth's surface.

    PubMed

    Madronich, S; McKenzie, R L; Björn, L O; Caldwell, M M

    1998-10-01

    being used, together with models of atmospheric transmission, to provide global coverage and long-term estimates of surface UV-B radiation. Estimates of long-term (1979-1992) trends in zonally averaged UV irradiances that include cloud effects are nearly identical to those for clear-sky estimates, providing evidence that clouds have not influenced the UV-B trends. However, the limitations of satellite-derived UV estimates should be recognized. To assess uncertainties inherent in this approach, additional validations involving comparisons with ground-based observations are required. Direct comparisons of ground-based UV-B radiation measurements between a few mid-latitude sites in the Northern and Southern Hemispheres have shown larger differences than those estimated using satellite data. Ground-based measurements show that summertime erythemal UV irradiances in the Southern Hemisphere exceed those at comparable latitudes of the Northern Hemisphere by up to 40%, whereas corresponding satellite-based estimates yield only 10-15% differences. Atmospheric pollution may be a factor in this discrepancy between ground-based measurements and satellite-derived estimates. UV-B measurements at more sites are required to determine whether the larger observed differences are globally representative. High levels of UV-B radiation continue to be observed in Antarctica during the recurrent spring-time ozone hole. For example, during ozone-hole episodes, measured biologically damaging radiation at Palmer Station, Antarctica (64 degrees S) has been found to approach and occasionally even exceed maximum summer values at San Diego, CA, USA (32 degrees N). Long-term predictions of future UV-B levels are difficult and uncertain. Nevertheless, current best estimates suggest that a slow recovery to pre-ozone depletion levels may be expected during the next half-century. (ABSTRACT TRUNCATED) PMID:9894350

  7. Flavonoids from the Genus Astragalus: Phytochemistry and Biological Activity.

    PubMed

    Bratkov, Viktor M; Shkondrov, Aleksandar M; Zdraveva, Petranka K; Krasteva, Ilina N

    2016-01-01

    Flavonoids, the most common plant polyphenols are widely distributed in every species and possess a broad range of pharmacological activities. The genus Astragalus is the largest in the Fabaceae family with more than 2,500 species spread. They are known to contain different metabolites such as flavonoids, saponins, and polysaccharides. Plants from the genus have been used in the traditional medicine of many countries for centuries. This paper is focused on the large group of flavonoid compounds. Details on structure as well as information about the pharmacological properties of flavonoids, isolated from Astragalus species have been discussed. This review is based on publications until the first half of 2014 and includes also the results from our phytochemical investigations of the genus. PMID:27041870

  8. Phytochemical and Biological Activities of Four Wild Medicinal Plants

    PubMed Central

    Ahmad, Shabir; AbdEl-Salam, Naser M.; Fouad, H.; Rehman, Najeeb Ur; Hussain, Hidayat; Saeed, Wajid

    2014-01-01

    The fruits of four wild plants, namely, Capparis decidua, Ficus carica, Syzygium cumini, and Ziziphus jujuba, are separately used as traditional dietary and remedial agents in remote areas of Khyber Pakhtunkhwa, Pakistan. The results of our study on these four plants revealed that the examined fruits were a valuable source of nutraceuticals and exhibited good level of antimicrobial activity. The fruits of these four investigated plants are promising source of polyphenols, flavonoids, alkaloids, terpenoids, and saponins. These four plants' fruits are good sources of iron, zinc, copper, manganese, selenium, and chromium. It was also observed that these fruits are potential source of antioxidant agent and the possible reason could be that these samples had good amount of phytochemicals. Hence, the proper propagation, conservation, and chemical investigation are recommended so that these fruits should be incorporated for the eradication of food and health related problems. PMID:25374941

  9. Amazon acai: chemistry and biological activities: a review.

    PubMed

    Yamaguchi, Klenicy Kazumy de Lima; Pereira, Luiz Felipe Ravazi; Lamarão, Carlos Victor; Lima, Emerson Silva; da Veiga-Junior, Valdir Florêncio

    2015-07-15

    Acai (acai or assai) is one of the Amazon's most popular functional foods and widely used in the world. There are many benefits to its alleged use in the growing market for nutraceuticals. The acai extracts have a range of polyphenolic components with antioxidant properties, some of those present in greater quantity are orientin, isoorientin and vanillic acid, as well as anthocyanins cyanidin-3-glucoside and cyanidin-3-rutinoside. The presence of these substances is linked mainly to the antioxidant, anti- inflammatory, anti-proliferative and cardioprotective activities. Importantly, there are two main species of the Euterpe genus which produce acai. There are several differences between them but they are still quite unknown, from literature to producers and consumers. In this review are highlighted the chemical composition, botanical aspects, pharmacological, marketing and nutrition of these species based on studies published in the last five years in order to unify the current knowledge and dissimilarities between them. PMID:25722148

  10. Flavonoids from the Genus Astragalus: Phytochemistry and Biological Activity

    PubMed Central

    Bratkov, Viktor M.; Shkondrov, Aleksandar M.; Zdraveva, Petranka K.; Krasteva, Ilina N.

    2016-01-01

    Flavonoids, the most common plant polyphenols are widely distributed in every species and possess a broad range of pharmacological activities. The genus Astragalus is the largest in the Fabaceae family with more than 2,500 species spread. They are known to contain different metabolites such as flavonoids, saponins, and polysaccharides. Plants from the genus have been used in the traditional medicine of many countries for centuries. This paper is focused on the large group of flavonoid compounds. Details on structure as well as information about the pharmacological properties of flavonoids, isolated from Astragalus species have been discussed. This review is based on publications until the first half of 2014 and includes also the results from our phytochemical investigations of the genus. PMID:27041870

  11. Phytochemical and biological activities of four wild medicinal plants.

    PubMed

    Shad, Anwar Ali; Ahmad, Shabir; Ullah, Riaz; AbdEl-Salam, Naser M; Fouad, H; Ur Rehman, Najeeb; Hussain, Hidayat; Saeed, Wajid

    2014-01-01

    The fruits of four wild plants, namely, Capparis decidua, Ficus carica, Syzygium cumini, and Ziziphus jujuba, are separately used as traditional dietary and remedial agents in remote areas of Khyber Pakhtunkhwa, Pakistan. The results of our study on these four plants revealed that the examined fruits were a valuable source of nutraceuticals and exhibited good level of antimicrobial activity. The fruits of these four investigated plants are promising source of polyphenols, flavonoids, alkaloids, terpenoids, and saponins. These four plants' fruits are good sources of iron, zinc, copper, manganese, selenium, and chromium. It was also observed that these fruits are potential source of antioxidant agent and the possible reason could be that these samples had good amount of phytochemicals. Hence, the proper propagation, conservation, and chemical investigation are recommended so that these fruits should be incorporated for the eradication of food and health related problems. PMID:25374941

  12. Modeling Activity: Ions to Hydrophobics in Crowded Biological Solutions

    NASA Astrophysics Data System (ADS)

    Pettitt, Montgomery

    2006-03-01

    Nonideal solutions play a role in many aspects of chemistry. As concentrations increase, concentration itself becomes a less useful quantity to understand equilibria. Industrial and medicinal chemistry often fail due to the difference between concentration and activity. An understanding of the impact of the crowded conditions in the cytoplasm on its biomolecules is of clear importance to biochemical, medical and pharmaceutical science. Work on the use of small biochemical compounds to crowd protein solutions indicates that a quantitative description of their non-ideal behavior is possible and straightforward. Here, we will show what the structural origin of this non-ideal solution behavior is from expression derived from a semi grand ensemble approach. We discuss the consequences of these findings regarding protein folding stability and solvation in crowded solutions through a structural analysis of the m-value or the change in free energy difference of a macromolecule in solution with respect to the concentration of a third component.

  13. Synthesis and biological activity of arylspiroborate salts derived from caffeic Acid phenethyl ester.

    PubMed

    Hébert, Martin J G; Flewelling, Andrew J; Clark, Trevor N; Levesque, Natalie A; Jean-François, Jacques; Surette, Marc E; Gray, Christopher A; Vogels, Christopher M; Touaibia, Mohamed; Westcott, Stephen A

    2015-01-01

    Two novel boron compounds containing caffeic acid phenethyl ester (CAPE) derivatives have been prepared and characterized fully. These new compounds and CAPE have been investigated for potential antioxidant and antimicrobial properties and their ability to inhibit 5-lipoxygenase and whether chelation to boron improves their biological activity. Sodium salt 4 was generally more active than ammonium salt 5 in the biological assays and surpassed the radical scavenging ability of CAPE. Compounds 4 and 5 were more active than CAPE and Zileuton in human polymorphonuclear leukocytes. These results clearly show the effectiveness of the synthesized salts as transporter of CAPE. PMID:25834744

  14. Diversity of Secondary Metabolites from Marine Bacillus Species: Chemistry and Biological Activity

    PubMed Central

    Mondol, Muhammad Abdul Mojid; Shin, Hee Jae; Islam, Mohammad Tofazzal

    2013-01-01

    Marine Bacillus species produce versatile secondary metabolites including lipopeptides, polypeptides, macrolactones, fatty acids, polyketides, and isocoumarins. These structurally diverse compounds exhibit a wide range of biological activities, such as antimicrobial, anticancer, and antialgal activities. Some marine Bacillus strains can detoxify heavy metals through reduction processes and have the ability to produce carotenoids. The present article reviews the chemistry and biological activities of secondary metabolites from marine isolates. Side by side, the potential for application of these novel natural products from marine Bacillus strains as drugs, pesticides, carotenoids, and tools for the bioremediation of heavy metal toxicity are also discussed. PMID:23941823

  15. Diversity of secondary metabolites from marine Bacillus species: chemistry and biological activity.

    PubMed

    Mondol, Muhammad Abdul Mojid; Shin, Hee Jae; Islam, Mohammad Tofazzal

    2013-08-01

    Marine Bacillus species produce versatile secondary metabolites including lipopeptides, polypeptides, macrolactones, fatty acids, polyketides, and isocoumarins. These structurally diverse compounds exhibit a wide range of biological activities, such as antimicrobial, anticancer, and antialgal activities. Some marine Bacillus strains can detoxify heavy metals through reduction processes and have the ability to produce carotenoids. The present article reviews the chemistry and biological activities of secondary metabolites from marine isolates. Side by side, the potential for application of these novel natural products from marine Bacillus strains as drugs, pesticides, carotenoids, and tools for the bioremediation of heavy metal toxicity are also discussed. PMID:23941823

  16. Synthesis and Biological Activity of Arylspiroborate Salts Derived from Caffeic Acid Phenethyl Ester

    PubMed Central

    Hébert, Martin J. G.; Flewelling, Andrew J.; Clark, Trevor N.; Jean-François, Jacques; Surette, Marc E.; Gray, Christopher A.; Vogels, Christopher M.; Touaibia, Mohamed; Westcott, Stephen A.

    2015-01-01

    Two novel boron compounds containing caffeic acid phenethyl ester (CAPE) derivatives have been prepared and characterized fully. These new compounds and CAPE have been investigated for potential antioxidant and antimicrobial properties and their ability to inhibit 5-lipoxygenase and whether chelation to boron improves their biological activity. Sodium salt 4 was generally more active than ammonium salt 5 in the biological assays and surpassed the radical scavenging ability of CAPE. Compounds 4 and 5 were more active than CAPE and Zileuton in human polymorphonuclear leukocytes. These results clearly show the effectiveness of the synthesized salts as transporter of CAPE. PMID:25834744

  17. Novel chlorinated dibenzofurans isolated from the cellular slime mold, Polysphondylium filamentosum, and their biological activities.

    PubMed

    Kikuchi, Haruhisa; Kubohara, Yuzuru; Nguyen, Van Hai; Katou, Yasuhiro; Oshima, Yoshiteru

    2013-08-01

    Cellular slime molds are expected to have the huge potential for producing secondary metabolites including polyketides, and we have studied the diversity of secondary metabolites of cellular slime molds for their potential utilization as new biological resources for natural product chemistry. From the methanol extract of fruiting bodies of Polysphondylium filamentosum, we obtained new chlorinated benzofurans Pf-1 (4) and Pf-2 (5) which display multiple biological activities; these include stalk cell differentiation-inducing activity in the well-studied cellular slime mold, Dictyostelium discoideum, and inhibitory activities on cell proliferation in mammalian cells and gene expression in Drosophila melanogaster. PMID:23746784

  18. Hyphenated Analytical Methods in Determination of Biologically Active Compounds in Hen's Eggs.

    PubMed

    Walczak, Justyna; Bocian, Szymon; Trziszka, Tadeusz; Buszewski, Bogusław

    2016-05-01

    Hen's egg is a complete material needed for the development of the embryo; it is an important source of nutraceutical compounds, such as protein, fats, vitamins, trace metals, and minerals. Moreover, avian egg contains biologically active compounds that exhibit antibacterial and antimicrobial activities as well as antitumor, antiviral, antioxidant, immunomodulating, and therapeutic properties. Eggs are mostly very good sources of valuable, easily digestible proteins. This review focuses on the biologically active compounds from hen's egg and applications of these compounds in medicine and the pharmaceutical industry. Additionally, it gives an overview of the hyphenated separation techniques, including sample preparation, analysis, and identification, used in the proteomics and lipidomics analysis. PMID:26186292

  19. In Search of a Better Bean: A Simple Activity to Introduce Plant Biology

    ERIC Educational Resources Information Center

    Spaccarotella, Kim; James, Roxie

    2014-01-01

    Measuring plant stem growth over time is a simple activity commonly used to introduce concepts in growth and development in plant biology (Reid & Pu, 2007). This Quick Fix updates the activity and incorporates a real-world application: students consider possible effects of soil substrate and sunlight conditions on plant growth without needing…

  20. Comparison of ground and aerial application, fungicide deposition and biological activity in large pecan tree canopies.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The study was conducted to determine vertical spray deposition in pecan canopies of large trees and to estimate the biological activity of the deposited fungicides. Tracer elements were used at molar concentrations equivalent to the molar amount of active ingredient found in the recommended rates o...

  1. [Advances in studies on chemical constituents and biological activities of Desmodium species].

    PubMed

    Liu, Chao; Wu, Ying; Zhang, Qian-Jun; Kang, Wen-Yi; Zhang, Long; Zhou, Qing-Di

    2013-12-01

    The chemical constituents isolated from Desmodium species (Leguminosae) included terpenoids, flavonoids, steroids, alkaloids compounds. Modem pharmacological studies have showed that the Desmodium species have antioxidant, antibacterial, anti-inflammatory, hepatoprotective, diuretic, antipyretic, analgesic and choleretic activity. This article mainly has reviewed the research advances of chemical constituents and biological activities of Desmodium species since 2003. PMID:24791478

  2. Physical Activity: A Tool for Improving Health (Part 1--Biological Health Benefits)

    ERIC Educational Resources Information Center

    Gallaway, Patrick J.; Hongu, Nobuko

    2015-01-01

    Extension educators have been promoting and incorporating physical activities into their community-based programs and improving the health of individuals, particularly those with limited resources. This article is the first of a three-part series describing the benefits of physical activity for human health: 1) biological health benefits of…

  3. A Preliminary Study of the Microbial Resources and Their Biological Activities of the East China Sea

    PubMed Central

    Lu, Xiaoling; Liu, Xiaoyu; Long, Cong; Wang, Guoxiang; Gao, Yun; Liu, Junhua; Jiao, Binghua

    2011-01-01

    East China Sea is one of the four sea areas in China, which possesses peculiar ecological environment and many kinds of living creatures, especially the microorganisms. We established the East China Sea microorganism library (during 2006–2010) for the first time, which stored about 30000 strains that covered most kinds of the species. In this paper, 395 pure strains of East China Sea microorganism library which belong to 33 different genera were mainly introduced. Sulfitobacter, Halomonas, Bacillus, Pseudoalteromonas, and Idiomarina were the most dominant species. On the large-scale biological activity screening of the 395 strains, 100 strains possess different biological activities based on different screening models, of which 11.4% strains have antibacterial activities, 15.9% have cytotoxicity activities, and 6.1% have antioxidation activities. Besides, the secondary metabolites of 6 strains with strong biological activities were studied systematically; diketopiperazines and macrocyclic lactones are the active secondary metabolites. The species and the biological activity of microorganisms diversity, the abundant structure type of the secondary metabolites, and their bioactivities all indicate that East China Sea is a potent marine microorganisms-derived developing resource for drug discovery. PMID:21789045

  4. Low Budget Biology II: A Collection of Low Cost Labs and Activities.

    ERIC Educational Resources Information Center

    Wartski, Bert; Wartski, Lynn Marie

    This document contains 13 low budget labs, demonstrations, and activities to be used in the biology classroom. Each activity has a teacher preparation section which states the purpose of each lab, some basic information, a list of materials and what they do, and how to prep the different solutions and chemicals. All labs are designed for a…

  5. Preparation of ferric-activated sludge-based adsorbent from biological sludge for tetracycline removal.

    PubMed

    Yang, Xin; Xu, Guoren; Yu, Huarong; Zhang, Zhao

    2016-07-01

    Ferric activation was novelly used to produce sludge-based adsorbent (SBA) from biological sludge through pyrolysis, and the adsorbents were applied to remove tetracycline from aqueous solution. The pyrolysis temperature and mass ratio (activator/dried sludge) greatly influenced the surface area and pore characteristics of SBA. Ferric activation could promote the porous structure development of adsorbents, and the optimum preparation conditions were pyrolysis temperature 750°C and mass ratio (activator/dried sludge) 0.5. In batch experiments, ferric-activated SBA showed a higher adsorption capacity for tetracycline than non-activated SBA, because the enhanced mesoporous structure favored the diffusion of tetracycline into the pores, the iron oxides and oxygen-containing functional groups in the adsorbents captured tetracycline by surface complexation. The results indicate that ferric activation is an effective approach for preparing adsorbents from biological sludge to remove tetracycline, providing a potential option for waste resource recovery. PMID:27038265

  6. Mineralogical characteristics of the silica polymorphs in relation to their biological activities

    SciTech Connect

    Guthrie, G.D. Jr.; Heaney, P.J.

    1993-10-01

    Numerous aspects of minerals (including the silica polymorphs) can effect their biological activities. These include periodic structures, compositional variations, dissolution characteristics, surface properties, and particle size/shape. In order to understand mineral-induced pathogenesis in a mechanistic way, the links between these properties and biochemical processes must be elucidated. This paper presents some of the basic properties of the silica polymorphs that may relate to pathogenicity and mineralogical strategies for designing biological assays to evaluate these properties.

  7. The Rise and Fall of Jasmonate Biological Activities.

    PubMed

    Heitz, Thierry; Smirnova, Ekaterina; Widemann, Emilie; Aubert, Yann; Pinot, Franck; Ménard, Rozenn

    2016-01-01

    Jasmonates (JAs) constitute a major class of plant regulators that coordinate responses to biotic and abiotic threats and important aspects of plant development. The core biosynthetic pathway converts linolenic acid released from plastid membrane lipids to the cyclopentenone cis-oxo-phytodienoic acid (OPDA) that is further reduced and shortened to jasmonic acid (JA) in peroxisomes. Abundant pools of OPDA esterified to plastid lipids also occur upon stress, mainly in the Arabidopsis genus. Long thought to be the bioactive hormone, JA only gains its pleiotropic hormonal properties upon conjugation into jasmonoyl-isoleucine (JA-Ile). The signaling pathway triggered when JA-Ile promotes the assembly of COI1-JAZ (Coronatine Insensitive 1-JAsmonate Zim domain) co-receptor complexes has been the focus of most recent research in the jasmonate field. In parallel, OPDA and several other JA derivatives are recognized for their separate activities and contribute to the diversity of jasmonate action in plant physiology. We summarize in this chapter the properties of different bioactive JAs and review elements known for their perception and signal transduction. Much progress has also been gained on the enzymatic processes governing JA-Ile removal. Two JA-Ile catabolic pathways, operating through ω-oxidation (cytochromes P450) or conjugate cleavage (amido hydrolases) shape signal dynamics to allow optimal control on defense. JA-Ile turnover not only participates in signal attenuation, but also impact the homeostasis of the entire JA metabolic pathway. PMID:27023244

  8. Multiple biological activities of human recombinant interleukin 1.

    PubMed Central

    Dinarello, C A; Cannon, J G; Mier, J W; Bernheim, H A; LoPreste, G; Lynn, D L; Love, R N; Webb, A C; Auron, P E; Reuben, R C

    1986-01-01

    Complementary DNA coding for human monocyte interleukin 1 (IL-1), pI 7 form, was expressed in Escherichia coli. During purification, IL-1 activity on murine T cells was associated with the recombinant protein. Homogeneous human recombinant IL-1 (hrIL-1) was tested in several assays to demonstrate the immunological and inflammatory properties attributed to this molecule. hrIL-1 induced proliferative responses in a cloned murine T cell in the presence of suboptimal concentrations of mitogen, whereas no effect was observed with hrIL-1 alone. At concentrations of 0.05 ng/ml, hrIL-1 doubled the response to mitogen (5 X 10(6) half maximal units/mg). Human peripheral blood T cells depleted of adherent cells underwent a blastogenic response and released interleukin 2 in the presence of hrIL-1 and mitogen. hrIL-1 was a potent inflammatory agent by its ability to induce human dermal fibroblast prostaglandin E2 production in vitro and to produce monophasic (endogenous pyrogen) fever when injected into rabbits or endotoxin-resistant mice. These studies establish that the dominant pI 7 form of recombinant human IL-1 possesses immunological and inflammatory properties and acts on the central nervous system to produce fever. Images PMID:3519678

  9. Monitoring the biological activity of abdominal aortic aneurysms Beyond Ultrasound.

    PubMed

    Forsythe, Rachael O; Newby, David E; Robson, Jennifer M J

    2016-06-01

    Abdominal aortic aneurysms (AAAs) are an important cause of morbidity and, when ruptured, are associated with >80% mortality. Current management decisions are based on assessment of aneurysm diameter by abdominal ultrasound. However, AAA growth is non-linear and rupture can occur at small diameters or may never occur in those with large AAAs. There is a need to develop better imaging biomarkers that can identify the potential risk of rupture independent of the aneurysm diameter. Key pathobiological processes of AAA progression and rupture include neovascularisation, necrotic inflammation, microcalcification and proteolytic degradation of the extracellular matrix. These processes represent key targets for emerging imaging techniques and may confer an increased risk of expansion or rupture over and above the known patient-related risk factors. Magnetic resonance imaging, using ultrasmall superparamagnetic particles of iron oxide, can identify and track hotspots of macrophage activity. Positron emission tomography, using a variety of targeted tracers, can detect areas of inflammation, angiogenesis, hypoxia and microcalcification. By going beyond the simple monitoring of diameter expansion using ultrasound, these cellular and molecular imaging techniques may have the potential to allow improved prediction of expansion or rupture and to better guide elective surgical intervention. PMID:26879242

  10. Alternative methods of terminal sterilization for biologically active macromolecules.

    PubMed

    Yaman, A

    2001-11-01

    The traditional perception within the pharmaceutical industry of the manufacture of injectable drug products is that active pharmaceutical ingredients (API) that are peptides, proteins or biopolymers, such as poly(DL-lactide) (PLA) and poly(DL-lactideco-glycolide) (PLGA), cannot be terminally sterilized. This perception exists largely because terminal sterilization is assumed by many to be only carried out by steam sterilization in a standard autoclave. Thus, it is understood that these API candidates must be manufactured by aseptic techniques. With the current technological advances in the area of protein and peptide sterilization, which has largely come from the food industry and has in recent years been developed for pharmaceutical use, techniques have been developed for the terminal sterilization of thermally sensitive APIs and biopolymers. In this review, the focus will be on the four major types of sterilization that are presented in the literature: (i) gamma-irradiation; (ii) e-Beam; (iii) natural light; and (iv) microwave. Each of these sterilization techniques present advantages and disadvantages for use in large-scale terminal sterilization of bioactive macromolecules. PMID:11899616

  11. Structure of Biologically Active Organotin(IV) Dithiocarbamates

    NASA Astrophysics Data System (ADS)

    Farina, Y.; Sanuddin, M.; Yamin, B. M.

    2008-03-01

    The diorganotin(IV) complexes of dithiocarbamates derived from from N-ethyl-n-propylamine (EtPrdtc), 2-dimethylaminoethylamine (Me2Etdtc), 3-dimethlyamino-1-propylamine (Me2Prdtc), p-tolylmethanamine (TylMetdtc) and N-methyl-1-phenylmethanamine (MePhMetdtc) have been synthesized and characterized. Single crystal X-ray diffraction studies on Ph3Sn(EtPrdtc), Me2Sn(MePhMetdtc)2 and Bu2Sn(MePhMetdtc)2 showed that the complexes adopted a monoclinic system with space group P(2)/n, P21/n and C2/c, respectively. The Ph3Sn(EtPrdtc) complex adopted a trigonal pyramidal structure while the Me2Sn(MePhMetdtc)2 and Bu2Sn(MePhMetdtc)2 complexes displayed structures which may be described as distorted octahedrons. Cytotoxicity test using HL60 cells (human promyelocytic leukemic) showed that only Me2Sn(Me2Etdtc), Me2Sn(MePhMetdtc)2 and Bu2Sn(MePhMetdtc)2 complexes were active. The rest of the complexes did not show cytotoxicity behaviour towards HL60 cells.

  12. Monitoring the biological activity of abdominal aortic aneurysms Beyond Ultrasound

    PubMed Central

    Forsythe, Rachael O; Newby, David E; Robson, Jennifer M J

    2016-01-01

    Abdominal aortic aneurysms (AAAs) are an important cause of morbidity and, when ruptured, are associated with >80% mortality. Current management decisions are based on assessment of aneurysm diameter by abdominal ultrasound. However, AAA growth is non-linear and rupture can occur at small diameters or may never occur in those with large AAAs. There is a need to develop better imaging biomarkers that can identify the potential risk of rupture independent of the aneurysm diameter. Key pathobiological processes of AAA progression and rupture include neovascularisation, necrotic inflammation, microcalcification and proteolytic degradation of the extracellular matrix. These processes represent key targets for emerging imaging techniques and may confer an increased risk of expansion or rupture over and above the known patient-related risk factors. Magnetic resonance imaging, using ultrasmall superparamagnetic particles of iron oxide, can identify and track hotspots of macrophage activity. Positron emission tomography, using a variety of targeted tracers, can detect areas of inflammation, angiogenesis, hypoxia and microcalcification. By going beyond the simple monitoring of diameter expansion using ultrasound, these cellular and molecular imaging techniques may have the potential to allow improved prediction of expansion or rupture and to better guide elective surgical intervention. PMID:26879242

  13. Rubus fruticosus L.: constituents, biological activities and health related uses.

    PubMed

    Zia-Ul-Haq, Muhammad; Riaz, Muhammad; De Feo, Vincenzo; Jaafar, Hawa Z E; Moga, Marius

    2014-01-01

    Rubus fruticosus L. is a shrub famous for its fruit called blackberry fruit or more commonly blackberry. The fruit has medicinal, cosmetic and nutritive value. It is a concentrated source of valuable nutrients, as well as bioactive constituents of therapeutic interest highlighting its importance as a functional food. Besides use as a fresh fruit, it is also used as ingredient in cooked dishes, salads and bakery products like jams, snacks, desserts, and fruit preserves. R. fruticosus contains vitamins, steroids and lipids in seed oil and minerals, flavonoids, glycosides, terpenes, acids and tannins in aerial parts that possess diverse pharmacological activities such as antioxidant, anti-carcinogenic, anti-inflammatory, antimicrobial anti-diabetic, anti-diarrheal, and antiviral. Various agrogeoclimatological factors like cultivar, environmental conditions of the area, agronomic practices employed, harvest time, post-harvest storage and processing techniques all influence the nutritional composition of blackberry fruit. This review focuses on the nutrients and chemical constituents as well as medicinal properties of different parts of R. fruticosus. Various cultivars and their physicochemical characteristics, polyphenolic content and ascorbic acid content are also discussed. The information in the present work will serve as baseline data and may lead to new biomedical applications of R. fruticosus as functional food. PMID:25072202

  14. Phytochemistry and biological activity of Spanish Citrus fruits.

    PubMed

    Gironés-Vilaplana, Amadeo; Moreno, Diego A; García-Viguera, Cristina

    2014-04-01

    The evaluation of the potential inhibitory activity on α-glucosidase and pancreatic lipase by Citrus spp. fruits of Spanish origin (lemon, orange, grapefruit, lime, and mandarin) together with the evaluation of their phytochemical content and antioxidant capacity (DPPH˙, ORACFL, ABTS(+), FRAP and O2˙(-)) aiming for new applications of the fruits in nutrition and health was carried out. As far as we are aware, the presence of 3-O-caffeoylferuoylquinic acid and two hydrated feruloylquinic acids in orange and the presence of 3,5-diferuoylquinic acid in grapefruit have been reported for the first time. Although grapefruit showed higher contents of phytochemicals such as flavanones and vitamin C, lemon and lime showed higher potential for inhibitory effects on lipase, and lime also showed the best results for in vitro α-glucosidase inhibition. On the other hand, higher antioxidant capacity was reported for grapefruit, lemon and lime, which correlated well with their phytochemical composition. Based on the results, it could be concluded that Citrus fruits are of great value for nutrition and treatment of diet-related diseases such as obesity and diabetes, and consequently, a new field of interest in the food industry regarding new bioactive ingredients would be considered. PMID:24563112

  15. Polysaccharides from Arctium lappa L.: Chemical structure and biological activity.

    PubMed

    Carlotto, Juliane; de Souza, Lauro M; Baggio, Cristiane H; Werner, Maria Fernanda de P; Maria-Ferreira, Daniele; Sassaki, Guilherme L; Iacomini, Marcello; Cipriani, Thales R

    2016-10-01

    The plant Arctium lappa L. is popularly used to relieve symptoms of inflammatory disorders. A crude polysaccharide fraction (SAA) resulting of aqueous extraction of A. lappa leaves showed a dose dependent anti-edematogenic activity on carrageenan-induced paw edema, which persisted for up to 48h. Sequential fractionation by ultrafiltration at 50kDa and 30kDa cut-off membranes yielded three fractions, namely RF50, RF30, and EF30. All these maintained the anti-edematogenic effect, but RF30 showed a more potent action, inhibiting 57% of the paw edema at a dose of 4.9mg/kg. The polysaccharide RF30 contained galacturonic acid, galactose, arabinose, rhamnose, glucose, and mannose in a 7:4:2:1:2:1 ratio and had a Mw of 91,000g/mol. Methylation analysis and NMR spectroscopy indicated that RF30 is mainly constituted by a type I rhamnogalacturonan branched by side chains of types I and II arabinogalactans, and arabinan. PMID:27311502

  16. Salicin derivatives from Salix glandulosa and their biological activities.

    PubMed

    Kim, Chung Sub; Subedi, Lalita; Park, Kyoung Jin; Kim, Sun Yeou; Choi, Sang Un; Kim, Ki Hyun; Lee, Kang Ro

    2015-10-01

    Two new salicin derivatives, saliglandin (1) and 6'-O-(Z)-p-coumaroylsalicin (2), along with fourteen known analogues (3-16) were isolated from the twigs of Salix glandulosa Seemen. The structures of 1-16 were characterized by the use of NMR methods ((1)H and (13)C NMR, (1)H-(1)H COSY, HSQC and HMBC), chemical hydrolysis, and GC/MS. The full NMR data assignment of the known compounds 6, 13, and 14 are reported for the first time. Isolated compounds were evaluated for their nitric oxide (NO) inhibitory efficacy in lipopolysaccharide (LPS)-activated microglial cell (BV-2). Compounds 2, 5, 8-16 significantly inhibited NO production, compound 11 being the most efficacious (IC50 13.57 μM) respectively. Moreover, compound 16 dramatically increased the nerve growth factor (NGF) production (165.24 ± 11.1%) in C6 glioma cells. Taken together, these results revealed that salicin derivatives from Salix glandulosa might have potent effect as anti-neuroinflammatory agents. PMID:26344424

  17. Organ- and species-specific biological activity of rosmarinic acid.

    PubMed

    Iswandana, R; Pham, B T; van Haaften, W T; Luangmonkong, T; Oosterhuis, D; Mutsaers, H A M; Olinga, P

    2016-04-01

    Rosmarinic acid (RA), a compound found in several plant species, has beneficial properties, including anti-inflammatory and antibacterial effects. We investigated the toxicity, anti-inflammatory, and antifibrotic effects of RA using precision-cut liver slices (PCLS) and precision-cut intestinal slices (PCIS) prepared from human, mouse, and rat tissue. PCLS and PCIS were cultured up to 48h in the absence or presence of RA. Gene expression of the inflammatory markers: IL-6, IL-8/CXCL1/KC, and IL-1β, as well as the fibrosis markers: pro-collagen 1a1, heat shock protein 47, α-smooth muscle actin, fibronectin (Fn2) and plasminogen activator inhibitor-1 (PAI-1) were evaluated by qPCR. RA was only toxic in murine PCIS. RA failed to mitigate the inflammatory response in most models, while it clearly reduced IL-6 and CXCL1/KC gene expression in murine PCIS at non-toxic concentrations. With regard to fibrosis, RA decreased the gene levels of Fn2 and PAI-1 in murine PCLS, and Fn2 in murine PCIS. Yet, no effect was observed on the gene expression of fibrosis markers in human and rat PCIS. In conclusion, we observed clear organ- and species-specific effects of RA. RA had little influence on inflammation. However, our study further establishes RA as a potential candidate for the treatment of liver fibrosis. PMID:26804033

  18. The biological activities of cinnamon, geranium and lavender essential oils.

    PubMed

    Sienkiewicz, Monika; Głowacka, Anna; Kowalczyk, Edward; Wiktorowska-Owczarek, Anna; Jóźwiak-Bębenista, Marta; Łysakowska, Monika

    2014-01-01

    Acinetobacter sp. represent an important cause of nosocomial infections. Their resistance to some antibiotics, their ability to survive on inanimate surfaces in the hospital environment and their ability to produce biofilms contributes to their virulence. The aim of the study was to determine the antibacterial properties of cinnamon, lavender and geranium essential oils against bacteria of the genus Acinetobacter isolated from several clinical materials and from the hospital environment. A comprehensive evaluation of the susceptibility of Acinetobacter sp. clinical strains to recommended antibiotics was performed. The constituents of cinnamon, lavender and geranium essential oils were identified by GC-FID-MS analysis, and their Minimal Inhibitory Concentrations (MICs) against tested clinical strains were determined by the micro-dilution broth method. In addition, the effects of essential oils on the viability of human microvascular endothelial cells (HMEC-1) and glioblastoma cell line (T98G) were evaluated. Cinnamon bark oil was the most active against clinical and environmental strains of Acinetobacter baumannii with MIC values ranging from 0.5 to 2.5 µL/mL. The MIC values for geranium oil were between 7.5 and 9.5 µL/mL, and between 10.5 and 13.0 µL/mL for lavender oil. These essential oils can be best employed in the fight against infections caused by bacteria from Acinetobacter genus as components of formulations for hygiene and disinfection of hospital environment. PMID:25514231

  19. Metal-dithiocarbamate complexes: chemistry and biological activity.

    PubMed

    Hogarth, Graeme

    2012-10-01

    Dithiocarbamates are highly versatile mono-anionic chelating ligands which form stable complexes with all the transition elements and also the majority of main group, lanthanide and actinide elements. They are easily prepared from primary or secondary amines and depending upon the nature of the cation can show good solubility in water or organic solvents. They are related to the thiuram disulfides by a one-electron redox process (followed by dimerisation via sulfur-sulfur bond formation) which is easily carried out upon addition of iodide or ferric salts. Dithiocarbamates are lipophilic and generally bind to metals in a symmetrical chelate fashion but examples of other coordination modes are known, the monodentate and anisobidentate modes being most prevalent. They are planar sterically non-demanding ligands which can be electronically tuned by judicious choice of substituents. They stabilize metals in a wide range of oxidation states, this being attributed to the existence of soft dithiocarbamate and hard thioureide resonance forms, the latter formally resulting from delocalization of the nitrogen lone pair onto the sulfurs, and consequently their complexes tend to have a rich electrochemistry. Tetraethyl thiuramdisulfide (disulfiram or antabuse) has been used as a drug since the 1950s but it is only recently that dithiocarbamate complexes have been explored within the medicinal domain. Over the past two decades anti-cancer activity has been noted for gold and copper complexes, technetium and copper complexes have been used in PET-imaging, dithiocarbamates have been used to treat acute cadmium poisoning and copper complexes also have been investigated as SOD inhibitors. PMID:22931592

  20. Severe Impingement of Lumbar Disc Replacements Increases the Functional Biological Activity of Polyethylene Wear Debris

    PubMed Central

    Baxter, Ryan M.; MacDonald, Daniel W.; Kurtz, Steven M.; Steinbeck, Marla J.

    2013-01-01

    Background: Wear, oxidation, and particularly rim impingement damage of ultra-high molecular weight polyethylene total disc replacement components have been observed following surgical revision. However, neither in vitro testing nor retrieval-based evidence has shown the effect(s) of impingement on the characteristics of polyethylene wear debris. Thus, we sought to determine (1) differences in polyethylene particle size, shape, number, or biological activity that correspond to mild or severe rim impingement and (2) in an analysis of all total disc replacements, regardless of impingement classification, whether there are correlations between the extent of regional damage and the characteristics of polyethylene wear debris. Methods: The extent of dome and rim damage was characterized for eleven retrieved polyethylene cores obtained at revision surgery after an average duration of implantation of 9.7 years (range, 4.6 to 16.1 years). Polyethylene wear debris was isolated from periprosthetic tissues with use of nitric acid and was imaged with use of environmental scanning electron microscopy. Subsequently, particle size, shape, number, biological activity, and chronic inflammation scores were determined. Results: Grouping of particles by size ranges that represented high biological relevance (<0.1 to 1-μm particles), intermediate biological relevance (1 to 10-μm particles), and low biological relevance (>10-μm particles) revealed an increased volume fraction of particles in the <0.1 to 1-μm and 1 to 10-μm size ranges in the mild-impingement cohort as compared with the severe-impingement cohort. The increased volume fractions resulted in a higher specific biological activity per unit particle volume in the mild-impingement cohort than in the severe-impingement cohort. However, functional biological activity, which is normalized by particle volume (mm3/g of tissue), was significantly higher in the severe-impingement cohort. This increase was due to a larger volume

  1. Glycoside vs. Aglycon: The Role of Glycosidic Residue in Biological Activity

    NASA Astrophysics Data System (ADS)

    Křen, Vladimír

    A large number of biologically active compounds are glycosides. Sometimes the glycosidic residue is crucial for their activity, in other cases glycosylation only improves pharmacokinetic parameters. Recent developments in molecular glycobiology brought better understanding of aglycon vs. glycoside activities, and made possible the development of new, more active or more effective glycodrugs based on these findings - a very illustrative recent example is vancomycin. The new enzymatic methodology "glycorandomization" enabled preparation of glycoside libraries and opened up paths to the preparation of optimized or entirely novel glycoside antibiotics. This chapter deals with an array of glycosidic compounds currently used in medicine but also covers the biological activity of some glycosidic metabolites of known drugs. The chapter discusses glycosides of vitamins, polyphenolic glycosides (flavonoids), alkaloid glycosides, glycosides of antibiotics, glycopeptides, cardiac glycosides, steroid and terpenoid glycosides etc. The physiological role of the glycosyl moiety and structure-activity relations (SAR) in the glycosidic moiety (-ies) are also discussed.

  2. Systematic Perturbations of Binuclear Non-heme Iron Sites: Structure and Dioxygen Reactivity of de Novo Due Ferri Proteins

    DOE PAGESBeta

    Snyder, Rae Ana; Betzu, Justine; Butch, Susan E.; Reig, Amanda J.; DeGrado, William F.; Solomon, Edward I.

    2015-07-08

    We report that DFsc (single-chain due ferri) proteins allow for modeling binuclear non-heme iron enzymes with a similar fold. Three 4A → 4G variants of DFsc were studied to investigate the effects of (1) increasing the size of the substrate/solvent access channel (G4DFsc), (2) including an additional His residue in the first coordination sphere along with three additional helix-stabilizing mutations [3His-G4DFsc(Mut3)], and (3) the three helix-stabilizing mutations alone [G4DFsc-(Mut3)] on the biferrous structures and their O2 reactivities. Near-infrared circular dichroism and magnetic circular dichroism (MCD) spectroscopy show that the 4A → 4G mutations increase coordination of the diiron site frommore » 4-coordinate/5-coordinate to 5-coordinate/5-coordinate, likely reflecting increased solvent accessibility. While the three helix-stabilizing mutations [G4DFsc(Mut3)] do not affect the coordination number, addition of the third active site His residue [3His-G4DFsc(Mut3)] results in a 5-coordinate/6-coordinate site. Although all 4A → 4G variants have significantly slower pseudo-first-order rates when reacting with excess O2 than DFsc (~2 s₋1), G4DFsc and 3His-G4DFsc(Mut3) have rates (~0.02 and ~0.04 s₋1) faster than that of G4DFsc(Mut3) (~0.002 s₋1). These trends in the rate of O2 reactivity correlate with exchange coupling between the Fe(II) sites and suggest that the two-electron reduction of O2 occurs through end-on binding at one Fe(II) rather than through a peroxy-bridged intermediate. Finally, UV–vis absorption and MCD spectroscopies indicate that an Fe(III)Fe(III)-OH species first forms in all three variants but converts into an Fe(III)-μ-OH-Fe(III) species only in the 2-His forms, a process inhibited by the additional active site His ligand that coordinatively saturates one of the iron centers in 3His-G4DFsc(Mut3).« less

  3. Binuclear rhenium carbonyl nitrosyls related to dicobalt octacarbonyl and their decarbonylation products.

    PubMed

    Xu, Bing; Li, Qian-Shu; Xie, Yaoming; King, R Bruce

    2016-07-01

    The geometries and thermochemistry of Re2(NO)4(CO) n (n = 4, 3, 2, 1, 0) structures isovalent with the binuclear cobalt carbonyls Co2(CO) n+4 have been examined using density functional theory. Eight low-energy Re2(NO)4(CO)4 structures, all with formal Re-Re single bonds, lie within 6 kcal mol(-1) of the global minimum. These eight structures include unbridged structures as well as structures with two bridging NO groups but no structures with bridging CO groups. Similarly, five low-energy Re2(NO)4(CO)3 structures, all with formal Re=Re double bonds, lie within 6 kcal mol(-1) of the global minimum. Again these five structures include unbridged structures as well as structures with one or two bridging NO groups but no structures with bridging CO groups. The Re2(NO)4(CO) n (n = 4, 3) appear to be fluxional systems similar to the well-known Co2(CO)8 for which doubly bridged and unbridged structures have approximately the same energies. The lowest energy Re2(NO)4(CO)2 structures have formal Re=Re double bonds including a structure with a five-electron donor bridging η(2)-μ-NO group. Isomeric Re2(NO)4(CO)2 structures with formal Re≡Re triple bonds lie approximately ∼10 kcal mol(-1) above the global minimum. For the more highly unsaturated Re2(NO)4(CO) and Re2(NO)4 systems, the lowest energy structures have formal Re≡Re triple bonds of length ∼2.6 Å. Higher energy Re2(NO)4(CO) structures have shorter Re-Re distances of length ∼2.5 Å suggesting formal quadruple bonds. Graphical Abstract The geometries and thermochemistry of Re2(NO)4(CO) n (n = 4, 3, 2, 1, 0) structures isovalent with the binuclear cobalt carbonyls Co2(CO) n+4 have been examined using density functional theory. A number of energetically closely spaced Re2(NO)4(CO)4 and Re2(NO)4(CO)3 structures are found, including unbridged and NO-bridged structures but no CO-bridged structures. The Re2(NO)4(CO) n (n = 2, 1, 0) systems provide examples of Re-Re multiple bonds of orders

  4. NetDecoder: a network biology platform that decodes context-specific biological networks and gene activities.

    PubMed

    da Rocha, Edroaldo Lummertz; Ung, Choong Yong; McGehee, Cordelia D; Correia, Cristina; Li, Hu

    2016-06-01

    The sequential chain of interactions altering the binary state of a biomolecule represents the 'information flow' within a cellular network that determines phenotypic properties. Given the lack of computational tools to dissect context-dependent networks and gene activities, we developed NetDecoder, a network biology platform that models context-dependent information flows using pairwise phenotypic comparative analyses of protein-protein interactions. Using breast cancer, dyslipidemia and Alzheimer's disease as case studies, we demonstrate NetDecoder dissects subnetworks to identify key players significantly impacting cell behaviour specific to a given disease context. We further show genes residing in disease-specific subnetworks are enriched in disease-related signalling pathways and information flow profiles, which drive the resulting disease phenotypes. We also devise a novel scoring scheme to quantify key genes-network routers, which influence many genes, key targets, which are influenced by many genes, and high impact genes, which experience a significant change in regulation. We show the robustness of our results against parameter changes. Our network biology platform includes freely available source code (http://www.NetDecoder.org) for researchers to explore genome-wide context-dependent information flow profiles and key genes, given a set of genes of particular interest and transcriptome data. More importantly, NetDecoder will enable researchers to uncover context-dependent drug targets. PMID:26975659

  5. NetDecoder: a network biology platform that decodes context-specific biological networks and gene activities

    PubMed Central

    da Rocha, Edroaldo Lummertz; Ung, Choong Yong; McGehee, Cordelia D.; Correia, Cristina; Li, Hu

    2016-01-01

    The sequential chain of interactions altering the binary state of a biomolecule represents the ‘information flow’ within a cellular network that determines phenotypic properties. Given the lack of computational tools to dissect context-dependent networks and gene activities, we developed NetDecoder, a network biology platform that models context-dependent information flows using pairwise phenotypic comparative analyses of protein–protein interactions. Using breast cancer, dyslipidemia and Alzheimer's disease as case studies, we demonstrate NetDecoder dissects subnetworks to identify key players significantly impacting cell behaviour specific to a given disease context. We further show genes residing in disease-specific subnetworks are enriched in disease-related signalling pathways and information flow profiles, which drive the resulting disease phenotypes. We also devise a novel scoring scheme to quantify key genes—network routers, which influence many genes, key targets, which are influenced by many genes, and high impact genes, which experience a significant change in regulation. We show the robustness of our results against parameter changes. Our network biology platform includes freely available source code (http://www.NetDecoder.org) for researchers to explore genome-wide context-dependent information flow profiles and key genes, given a set of genes of particular interest and transcriptome data. More importantly, NetDecoder will enable researchers to uncover context-dependent drug targets. PMID:26975659

  6. Structural Diversity and Biological Activities of Indole Diketopiperazine Alkaloids from Fungi.

    PubMed

    Ma, Yang-Min; Liang, Xi-Ai; Kong, Yang; Jia, Bin

    2016-09-01

    Indole diketopiperazine alkaloids are secondary metabolites of microorganisms that are widely distributed in filamentous fungi, especially in the genera Aspergillus and Penicillium of the phylum Ascomycota or sac fungi. These alkaloids represent a group of natural products characterized by diversity in both chemical structures and biological activities. This review aims to summarize 166 indole diketopiperazine alkaloids from fungi published from 1944 to mid-2015. The emphasis is on diverse chemical structures within these alkaloids and their relevant biological activities. The aim is to assess which of these compounds merit further study for purposes of drug development. PMID:27538469

  7. Characterization of the corrosion resistance of biologically active solutions: The effects of anodizing and welding

    NASA Technical Reports Server (NTRS)

    Walsh, Daniel W.

    1991-01-01

    An understanding of fabrication processes, metallurgy, electrochemistry, and microbiology is crucial to the resolution of microbiologically influenced corrosion (MIC) problems. The object of this effort was to use AC impedance spectroscopy to characterize the corrosion resistance of Type II anodized aluminum alloy 2219-T87 in sterile and biologically active media and to examine the corrosion resistance of 316L, alloy 2219-T87, and titanium alloy 6-4 in the welded and unwelded conditions. The latter materials were immersed in sterile and biologically active media and corrosion currents were measured using the polarization resistance (DC) technique.

  8. Structure Diversity, Synthesis, and Biological Activity of Cyathane Diterpenoids in Higher Fungi.

    PubMed

    Tang, Hao-Yu; Yin, Xia; Zhang, Cheng-Chen; Jia, Qian; Gao, Jin-Ming

    2015-01-01

    Cyathane diterpenoids, occurring exclusively in higher basidiomycete (mushrooms), represent a structurally diverse class of natural products based on a characteristic 5-6-7 tricyclic carbon scaffold, including 105 members reported to date. These compounds show a diverse range of biological activities, such as antimicrobial, anti-MRSA, agonistic toward the kappa-opioid receptor, antiinflammatory, anti-proliferative and nerve growth factor (NGF)-like properties. The present review focuses on the structure diversity, structure elucidation and biological studies of these compounds, including mechanisms of actions and structure-activity relationships (SARs). In addition, new progress in chemical synthesis of cyathane diterpenoids is discussed. PMID:25994862

  9. Electrostatic potentials of some dibenzo-p-dioxins in relation to their biological activities (journal version)

    SciTech Connect

    Murray, J.S.; Politzer, P.

    1987-01-01

    A computational analysis of the electrostatic potentials of eight halogenated dibenzo-p-dioxins was carried out at the ab initio SCF STO-5G level. It focuses upon the relationships between these potentials and the biological activities of the molecules, including toxicity, aryl hydrocarbon hydroxylase induction and receptor binding. In general, regions of negative potential are found to be associated with the oxygens and with the halogen substituents. Biological activity appears to be related to the presence of an optimum range of negative potentials above the lateral portions of the molecules in conjunction with a weakening of those near the oxygens.

  10. Two new biologically active cyclopentenones from Dasyscyphus sp. A47-98.

    PubMed

    Mierau, Viktor; Sterner, Olov; Anke, Timm

    2004-05-01

    Two new biological active cyclopentenones VM 4798-1a (1a) and VM 4798-1b (1b) were obtained as a 3:1 inseparable mixture from fermentations of Dasyscyphus sp. A47-98. The mixture of the two isomers showed cytotoxic and weak antibacterial and antifungal properties. VM 4898-1 (2-hydroxy-3,4-dimethyl-2-cyclopenten-1-one, 4), produced by another Dasyscyphus sp. showed no significant biological activity. The structures were elucidated by NMR techniques. PMID:15303491

  11. Astonishing diversity of natural surfactants: 6. Biologically active marine and terrestrial alkaloid glycosides.

    PubMed

    Dembitsky, Valery M

    2005-11-01

    This review article presents 209 alkaloid glycosides isolated and identified from plants, microorganisms, and marine invertebrates that demonstrate different biological activities. They are of great interest, especially for the medicinal and/or pharmaceutical industries. These biologically active glycosides have good potential for future chemical preparation of compounds useful as antioxidants, anticancer, antimicrobial, and antibacterial agents. These glycosidic compounds have been subdivided into several groups, including: acridone; aporphine; benzoxazinoid; ergot; indole; enediyne alkaloidal antibiotics; glycosidic lupine alkaloids; piperidine, pyridine, pyrrolidine, and pyrrolizidine alkaloid glycosides; glycosidic quinoline and isoquinoline alkaloids; steroidal glycoalkaloids; and miscellaneous alkaloid glycosides. PMID:16459921

  12. Characterization and in vitro biological activities of Thai traditional fermented shrimp pastes.

    PubMed

    Kleekayai, Thanyaporn; Saetae, Donlaporn; Wattanachaiyingyong, Ongart; Tachibana, Shinjiro; Yasuda, Masaaki; Suntornsuk, Worapot

    2015-03-01

    In this work, chemical and biological characteristics of two types of Thai fermented shrimp paste, Kapi Ta Dam and Kapi Ta Deang, at different fermentation periods and their raw materials were investigated. Kapi had low water activity and high proteins with high glutamic acid and lysine. Both Kapis, which had different sources, showed similar characteristics. The number of lactic acid bacteria in the products increased during the early stages of fermentation. Free α-amino acid contents in the products increased with the fermentation time. The water extracts from Kapi products showed strong antioxidative activities against ABTS(+) radical, and ACE inhibitory activity but they did not exhibit antimicrobial activity against Staphylococcus aureus, Bacillus cereus, Escherichia coli and Salmonella Typhimurium. Biological activities in Kapi could be developed by fermentation process, enzymatic hydrolysis of proteins and non-enzymatic browning reactions. Kapi could, thus, serve as a potential source of natural bioactive substances. PMID:25745266

  13. [Biological activity of lipids and photosynthetic pigments of Sargassum pallidum C. Agardh].

    PubMed

    Gerasimenko, N I; Martyias, E A; Logvinov, S V; Busarova, N G

    2014-01-01

    The biological activity of lipids and photosynthetic pigments of the kelp Sargassum pallidum (Turner) C. Agardh has been studied. Free fatty acids and their esters demonstrated considerable antimicrobial activity against bacteria (Staphylococcus aureus[ital] and Escherichia coli), yeast-like fungi (Candida albicans), and opportunistic pathogenic (Aspergilius niger) and phytopathogenic (Fusarium oxysporum, and Septoria glycines) fungi. Glyceroglycolipids and neutral lipids demonstrated moderate activity. Fucoxanthin and chlorophylls weakly suppressed the growth of microorganisms. None of the studied substances demonstrated activity against Ehrlich's carcinoma. It was shown that the season of weed harvesting affected both antimicrobial and hemolytic activities of different lipids due to changes in their fatty acid composition. PMID:25272757

  14. Biological activity of glycolipids produced by microorganisms: new trends and possible therapeutic alternatives.

    PubMed

    Cortés-Sánchez, Alejandro de Jesús; Hernández-Sánchez, Humberto; Jaramillo-Flores, María Eugenia

    2013-01-15

    Several biological processes in prokaryotic and eukaryotic organisms require the presence of glycolipids (biosurfactants), compounds with both hydrophilic and hydrophobic groups in their structure. They constitute the backbone of different metabolic functions and biological structures such as cell membranes. Besides being structural components, glycolipids show surface activity in the interfaces and are mainly produced by microorganisms. Interest in biosurfactants has increased considerably in recent times due to their applications in the environmental, oil, food, and pharmaceutical industries, since they have unique properties such as low toxicity, high biodegradability, environmentally friendly, foaming capacity, high selectivity and specificity at extreme temperatures, pH and salinity, as well as biological activity. All of these properties are considered advantages over other chemical surfactants, and therefore glycolipids are considered a good alternative, given the current interest on sustainable development. The present work shows a general view of bio-surfactants of microbial origin, particularly of glycolipids, referring to several studies on their biological activity that have revealed their great potential in the medical-biological field, discovering interesting possibilities for their therapeutic application in the near future. PMID:22959834

  15. Macrophage and colon tumor cells as targets for a binuclear silver(I) N-heterocyclic carbene complex, an anti-inflammatory and apoptosis mediator.

    PubMed

    Iqbal, Muhammad Adnan; Umar, Muhammad Ihtisham; Haque, Rosenani A; Khadeer Ahamed, Mohamed B; Asmawi, Mohd Zaini Bin; Majid, Amin Malik Shah Abdul

    2015-05-01

    Chronic inflammation intensifies the risk for malignant neoplasm, indicating that curbing inflammation could be a valid strategy to prevent or cure cancer. Cancer and inflammation are inter-related diseases and many anti-inflammatory agents are also used in chemotherapy. Earlier, we have reported a series of novel ligands and respective binuclear Ag(I)-NHC complexes (NHC=N-heterocyclic carbene) with potential anticancer activity. In the present study, a newly synthesized salt (II) and respective Ag(I)-NHC complex (III) of comparable molecular framework were prepared for a further detailed study. Preliminarily, II and III were screened against HCT-116 and PC-3 cells, wherein III showed better results than II. Both the compounds showed negligible toxicity against normal CCD-18Co cells. In FAM-FLICA caspase assay, III remarkably induced caspase-3/7 in HCT-116 cells most probably by tumor necrosis factor-alpha (TNF-α) independent intrinsic pathway and significantly inhibited in vitro synthesis of cytokines, interleukin-1 (IL-1) and TNF-α in human macrophages (U937 cells). In a cell-free system, both the compounds inhibited cyclooxygenase (COX) activities, with III being more selective towards COX-2. The results revealed that III has strong antiproliferative property selectively against colorectal tumor cells which could be attributed to its pro-apoptotic and anti-inflammatory abilities. PMID:25699476

  16. Synthesis, spectral and electrochemical studies of binuclear Ru(III) complexes containing dithiosemicarbazone ligand

    NASA Astrophysics Data System (ADS)

    Kanchana Devi, A.; Ramesh, R.

    2014-01-01

    Synthesis of several new octahedral binuclear ruthenium(III) complexes of the general composition [(EPh3)2(X)Ru-L-Ru(X)(EPh3)2] containing benzene dithiosemicarbazone ligands (where E = P or As; X = Cl or Br; L = binucleating ligands) is presented. All the complexes have been fully characterized by elemental analysis, FT-IR, UV-vis and EPR spectroscopy together with magnetic susceptibility measurements. IR study shows that the dithiosemicarbazone ligands behave as dianionic tridentate ligands coordinating through the oxygen atom of the deprotonated phenolic group, nitrogen atom of the azomethine group and thiolate sulphur. In DMF solution, all the complexes exhibit intense d-d transition and ligand-to-metal charge transfer (LMCT) transition in the visible region. The magnetic moment values of the complexes are in the range 1.78-1.82 BM, which reveals the presence of one unpaired electron on each metal ion. The EPR spectra of the liquid samples at LNT show the presence of three different 'g' values (gx ≠ gy ≠ gz) indicate a rhombic distortion around the ruthenium ion. All the complexes exhibit two quasi-reversible one electron oxidation responses (RuIII-RuIII/RuIII-RuIV; RuIII-RuIV/RuIV-RuIV) within the E1/2 range of 0.61-0.74 V and 0.93-0.98 V respectively, versus Ag/AgCl.

  17. Optical properties of a binuclear neodymium complex in phosphorus oxychloride for liquid laser

    NASA Astrophysics Data System (ADS)

    Zhang, Guofang; She, Jiangbo; Han, Kai; Nie, Rongzhi; Li, Dongdong; Peng, Bo

    2015-11-01

    A novel binuclear neodymium complex Nd(CF3COO)3·(Ph3PO)2 (Ph3PO: triphenylphosphine oxide) with high stimulated emission cross-section was presented. The molecular structure of the complex was characterized by single-crystal X-ray diffraction. The optical properties of the complex in liquid medium were studied. From the absorption and luminescence spectra, the Judd-Ofelt parameters of Nd(CF3COO)3·(Ph3PO)2 in phosphorus oxychloride were obtained. Based on the crystal structure, the effects of crystal field and bonding valence properties on three intensity parameters Ωt(t = 2, 4, 6) and emission cross-section were analyzed in detail. The emission cross-section of 4F3/2 → 4I11/2 fluorescence transition (2.78 × 10-20 cm2) of the new neodymium compound was higher than those of other Nd(III) complexes and even comparable with some laser glasses.

  18. Mono- and binuclear non-heme iron chemistry from a theoretical perspective.

    PubMed

    Rokob, Tibor András; Chalupský, Jakub; Bím, Daniel; Andrikopoulos, Prokopis C; Srnec, Martin; Rulíšek, Lubomír

    2016-09-01

    In this minireview, we provide an account of the current state-of-the-art developments in the area of mono- and binuclear non-heme enzymes (NHFe and NHFe2) and the smaller NHFe(2) synthetic models, mostly from a theoretical and computational perspective. The sheer complexity, and at the same time the beauty, of the NHFe(2) world represents a challenge for experimental as well as theoretical methods. We emphasize that the concerted progress on both theoretical and experimental side is a conditio sine qua non for future understanding, exploration and utilization of the NHFe(2) systems. After briefly discussing the current challenges and advances in the computational methodology, we review the recent spectroscopic and computational studies of NHFe(2) enzymatic and inorganic systems and highlight the correlations between various experimental data (spectroscopic, kinetic, thermodynamic, electrochemical) and computations. Throughout, we attempt to keep in mind the most fascinating and attractive phenomenon in the NHFe(2) chemistry, which is the fact that despite the strong oxidative power of many reactive intermediates, the NHFe(2) enzymes perform catalysis with high selectivity. We conclude with our personal viewpoint and hope that further developments in quantum chemistry and especially in the field of multireference wave function methods are needed to have a solid theoretical basis for the NHFe(2) studies, mostly by providing benchmarking and calibration of the computationally efficient and easy-to-use DFT methods. PMID:27229513

  19. Boosting the electron spin coherence in binuclear Mn complexes by multiple microwave pulses

    NASA Astrophysics Data System (ADS)

    Zaripov, R.; Vavilova, E.; Miluykov, V.; Bezkishko, I.; Sinyashin, O.; Salikhov, K.; Kataev, V.; Büchner, B.

    2013-09-01

    We investigate a possibility to enhance the coherence time of electron spins in magnetic molecular complexes by application of the Carr-Purcell-Meiboom-Gill (CPMG) multiple microwave pulse sequence. Our theoretical analysis shows that the CPMG sequence can efficiently suppress the spin decoherence channel arising due to spectral diffusion induced by a random modulation of the hyperfine interaction which is an important source of the spin dephasing in molecular magnets. We confirm this by employing the CPMG protocol in pulse electron spin resonance experiments on model binuclear 1,2-diphosphacyclopentadienyl manganese complexes. We show that, compared to the standardly used two-pulse primary spin-echo technique, the CPMG experiment can boost the phase memory time up to one order of magnitude, bringing it to above 10 μs at low temperatures. This finding may be important for the implementation of quantum computation protocols on molecular magnets. We discuss a possible interesting analogy with the Zeno's paradox in quantum theory (the Zeno quantum effect), which could be implicit in the CPMG experiment.

  20. Binuclear platinum (II)-terpyridine complexes. A new class of bifunctional DNA-intercalating agent.

    PubMed Central

    McFadyen, W D; Wakelin, L P; Roos, I A; Hillcoat, B L

    1986-01-01

    A series of binuclear DNA-binding ligands was prepared by linking two (2,2':6',2"-terpyridine)platinum(II) moieties via alpha omega-dithiols of the type HS-[CH2]n-SH where n = 4-10. A monomeric analogue was also synthesized. Compounds were characterized by elemental analysis and electronic and n.m.r. spectroscopy. Viscometric measurements with sonicated rod-like DNA fragments and covalently closed circular DNA were performed to investigate the mode of binding of these agents. The ligands with n = 5 and 6 function as bis intercalators and form a single 'base-pair sandwich' in violation of neighbour-exclusion binding. Bifunctional reaction occurs for the ligand with n = 7, whereas the ligands with n = 8 and 10 show a preference for mixed monofunctional/bifunctional binding. The data do not permit definitive assignment of the binding mode of the ligands with n = 4 and 9. All compounds are growth-inhibitory against mouse leukaemia L1210 cells in culture with IC50 values in the range 2-14 microM. PMID:3800959

  1. Hybrid binuclear-cobalt-phthalocyanine as oxygen reduction reaction catalyst in single chamber microbial fuel cells

    NASA Astrophysics Data System (ADS)

    Li, Baitao; Zhou, Xiuxiu; Wang, Xiujun; Liu, Bingchuan; Li, Baikun

    2014-12-01

    A novel hybrid binuclear-cobalt-phthalocyanine (Bi-CoPc) is developed as the cathode catalyst to replace the costly platinum (Pt) in single chamber microbial fuel cells (SCMFCs). Bi-CoPc/C is integrated with metal oxides (NiO and CoO) to form macrocyclic complex for enhanced oxygen reduction rate (ORR). The characteristics of hybrid catalysts (Bi-CoPc/C-CoO and Bi-CoPc/C-NiO) are compared with Co-contained catalysts (CoPc/C and Bi-CoPc/C) and metal oxide catalysts (NiO and CoO). The increase in O and N functional groups indicates the benefits of NiO and CoO to the cathode catalysts. The cyclic voltammetry (CV) shows the reduction peak for Bi-CoPc/C-NiO and Bi-CoPc/C-CoO at -0.12 V and -0.22 V, respectively. The power densities (368 mW m-2 and 400 mW m-2) of SCMFCs with Bi-CoPc/C-CoO and Bi-CoPc-NiO/C are the highest among the cathodes tested, and close to that of Pt (450 mW m-2). This study demonstrates that hybrid Bi-CoPc/C with metal oxides has a great potential as a cost-effective catalyst in MFCs.

  2. Synthesis, spectral and electrochemical studies of binuclear Ru(III) complexes containing dithiosemicarbazone ligand.

    PubMed

    Kanchana Devi, A; Ramesh, R

    2014-01-01

    Synthesis of several new octahedral binuclear ruthenium(III) complexes of the general composition [(EPh3)2(X)Ru-L-Ru(X)(EPh3)2] containing benzene dithiosemicarbazone ligands (where E=P or As; X=Cl or Br; L=binucleating ligands) is presented. All the complexes have been fully characterized by elemental analysis, FT-IR, UV-vis and EPR spectroscopy together with magnetic susceptibility measurements. IR study shows that the dithiosemicarbazone ligands behave as dianionic tridentate ligands coordinating through the oxygen atom of the deprotonated phenolic group, nitrogen atom of the azomethine group and thiolate sulphur. In DMF solution, all the complexes exhibit intense d-d transition and ligand-to-metal charge transfer (LMCT) transition in the visible region. The magnetic moment values of the complexes are in the range 1.78-1.82 BM, which reveals the presence of one unpaired electron on each metal ion. The EPR spectra of the liquid samples at LNT show the presence of three different 'g' values (gx≠gy≠gz) indicate a rhombic distortion around the ruthenium ion. All the complexes exhibit two quasi-reversible one electron oxidation responses (Ru(III)-Ru(III)/Ru(III)-Ru(IV); Ru(III)-Ru(IV)/Ru(IV)-Ru(IV)) within the E1/2 range of 0.61-0.74 V and 0.93-0.98 V respectively, versus Ag/AgCl. PMID:23988528

  3. Allosteric effects in binuclear homo- and heterometallic triple-stranded lanthanide podates.

    PubMed

    Ryan, Patrick E; Canard, Gabriel; Koeller, Sylvain; Bocquet, Bernard; Piguet, Claude

    2012-09-17

    This work illustrates a simple approach for deciphering and exploiting the various free energy contributions to the global complexation process leading to the binuclear triple-stranded podates [Ln(2)(L9)](6+) (Ln is a trivalent lanthanide). Despite the larger microscopic affinities exhibited by the binding sites for small Ln(3+), the stability constants measured for [Ln(2)(L9)](6+) decrease along the lanthanide series; a phenomenon which can be ascribed to the severe enthalpic penalty accompanying the intramolecular cyclization around small Ln(III), combined with increasing anticooperative allosteric interligand interactions. Altogether, the microscopic thermodynamic characteristics predict β(1,1,1)(La,Lu,L9)/β(1,1,1)(Lu,La,L9) = 145 for the ratio of the formation constants of the target heterobimetallic [LaLu(L9)](6+) and [LuLa(L9)](6+) microspecies, a value in line with the quantitative preparation (>90%) of [LaLu(L9)](6+) at millimolar concentrations. Preliminary NMR titrations indeed confirm the rare thermodynamic programming of a pure heterometallic f-f' complex. PMID:22946598

  4. Strongly coupled binuclear uranium-oxo complexes from uranyl oxo rearrangement and reductive silylation

    NASA Astrophysics Data System (ADS)

    Arnold, Polly L.; Jones, Guy M.; Odoh, Samuel O.; Schreckenbach, Georg; Magnani, Nicola; Love, Jason B.

    2012-03-01

    The most common motif in uranium chemistry is the d0f0 uranyl ion [UO2]2+ in which the oxo groups are rigorously linear and inert. Alternative geometries, such as the cis-uranyl, have been identified theoretically and implicated in oxo-atom transfer reactions that are relevant to environmental speciation and nuclear waste remediation. Single electron reduction is now known to impart greater oxo-group reactivity, but with retention of the linear OUO motif, and reactions of the oxo groups to form new covalent bonds remain rare. Here, we describe the synthesis, structure, reactivity and magnetic properties of a binuclear uranium-oxo complex. Formed through a combination of reduction and oxo-silylation and migration from a trans to a cis position, the new butterfly-shaped Si-OUO2UO-Si molecule shows remarkably strong UV-UV coupling and chemical inertness, suggesting that this rearranged uranium oxo motif might exist for other actinide species in the environment, and have relevance to the aggregation of actinide oxide clusters.

  5. Strongly coupled binuclear uranium-oxo complexes from uranyl oxo rearrangement and reductive silylation.

    PubMed

    Arnold, Polly L; Jones, Guy M; Odoh, Samuel O; Schreckenbach, Georg; Magnani, Nicola; Love, Jason B

    2012-03-01

    The most common motif in uranium chemistry is the d(0)f(0) uranyl ion [UO(2)](2+) in which the oxo groups are rigorously linear and inert. Alternative geometries, such as the cis-uranyl, have been identified theoretically and implicated in oxo-atom transfer reactions that are relevant to environmental speciation and nuclear waste remediation. Single electron reduction is now known to impart greater oxo-group reactivity, but with retention of the linear OUO motif, and reactions of the oxo groups to form new covalent bonds remain rare. Here, we describe the synthesis, structure, reactivity and magnetic properties of a binuclear uranium-oxo complex. Formed through a combination of reduction and oxo-silylation and migration from a trans to a cis position, the new butterfly-shaped Si-OUO(2)UO-Si molecule shows remarkably strong U(V)-U(V) coupling and chemical inertness, suggesting that this rearranged uranium oxo motif might exist for other actinide species in the environment, and have relevance to the aggregation of actinide oxide clusters. PMID:22354437

  6. Symphonia globulifera, a widespread source of complex metabolites with potent biological activities.

    PubMed

    Fromentin, Yann; Cottet, Kevin; Kritsanida, Marina; Michel, Sylvie; Gaboriaud-Kolar, Nicolas; Lallemand, Marie-Christine

    2015-01-01

    Symphonia globulifera has been widely used in traditional medicine and has therefore been subjected to several phytochemical studies in the American and African continents. Interestingly, some disparities have been observed concerning its metabolic profile. Several phytochemical studies of S. globulifera have led to the identification of more than 40 compounds, including several polycyclic polyprenylated acylphloroglucinols. Biological evaluations have pointed out the promising biological activities of these secondary metabolites, mostly as antiparasitic or antimicrobial, confirming the traditional use of this plant. The purpose of this review is to describe the natural occurrence, botanical aspects, ethnomedicinal use, structure, and biogenesis, as well as biological activities of compounds isolated from this species according to their provenance. PMID:25590372

  7. Temporal and spatial variability of soil biological activity at European scale

    NASA Astrophysics Data System (ADS)

    Mallast, Janine; Rühlmann, Jörg

    2015-04-01

    The CATCH-C project aims to identify and improve the farm-compatibility of Soil Management Practices including to promote productivity, climate change mitigation and soil quality. The focus of this work concentrates on turnover conditions for soil organic matter (SOM). SOM is fundamental for the maintenance of quality and functions of soils while SOM storage is attributed a great importance in terms of climate change mitigation. The turnover conditions depend on soil biological activity characterized by climate and soil properties. Soil biological activity was investigated using two model concepts: a) Re_clim parameter within the ICBM (Introductory Carbon Balance Model) (Andrén & Kätterer 1997) states a climatic factor summarizing soil water storage and soil temperature and its influence on soil biological activity. b) BAT (biological active time) approach derived from model CANDY (CArbon and Nitrogen Dynamic) (Franko & Oelschlägel 1995) expresses the variation of soil moisture, soil temperature and soil aeration as a time scale and an indicator of biological activity for soil organic matter (SOM) turnover. During an earlier stage both model concepts, Re_clim and BAT, were applied based on a monthly data to assess spatial variability of turnover conditions across Europe. This hampers the investigation of temporal variability (e.g. intra-annual). The improved stage integrates daily data of more than 350 weather stations across Europe presented by Klein Tank et al. (2002). All time series data (temperature, precipitation and potential evapotranspiration and soil texture derived from the European Soil Database (JRC 2006)), are used to calculate soil biological activity in the arable layer. The resulting BAT and Re_clim values were spatio-temporal investigated. While "temporal" refers to a long-term trend analysis, "spatial" includes the investigation of soil biological activity variability per environmental zone (ENZ, Metzger et al. 2005 representing similar

  8. From Synthesis to Biological Impact of Pd (II) Complexes: Synthesis, Characterization, and Antimicrobial and Scavenging Activity

    PubMed Central

    Sharma, Nitin Kumar; Ameta, Rakesh Kumar; Singh, Man

    2016-01-01

    The Pd (II) complexes with a series of halosubstituted benzylamine ligands (BLs) have been synthesized and characterized with different spectroscopic technique such as FTIR, UV/Vis, LCMS, 1H, and 13C NMR. Their molecular sustainability in different solvents such as DMSO, DMSO : H2O, and DMSO : PBS at physiological condition (pH 7.2) was determined by UV/Vis spectrophotometer. The in vitro antibacterial and antifungal activities of the complexes were investigated against Gram-positive and Gram-negative microbes and two different fungi indicated their significant biological potential. Additionally, their antioxidant activity has been analyzed with DPPH• free radical through spectrophotometric method and the result inferred them as an antioxidant. The stronger antibacterial and antioxidant activities of the synthesized complexes suggested them as a stronger antimicrobial agent. Our study advances the biological importance of palladium (II) amine complexes in the field of antimicrobial and antioxidant activities. PMID:27119023

  9. From Synthesis to Biological Impact of Pd (II) Complexes: Synthesis, Characterization, and Antimicrobial and Scavenging Activity.

    PubMed

    Sharma, Nitin Kumar; Ameta, Rakesh Kumar; Singh, Man

    2016-01-01

    The Pd (II) complexes with a series of halosubstituted benzylamine ligands (BLs) have been synthesized and characterized with different spectroscopic technique such as FTIR, UV/Vis, LCMS, (1)H, and (13)C NMR. Their molecular sustainability in different solvents such as DMSO, DMSO : H2O, and DMSO : PBS at physiological condition (pH 7.2) was determined by UV/Vis spectrophotometer. The in vitro antibacterial and antifungal activities of the complexes were investigated against Gram-positive and Gram-negative microbes and two different fungi indicated their significant biological potential. Additionally, their antioxidant activity has been analyzed with DPPH(•) free radical through spectrophotometric method and the result inferred them as an antioxidant. The stronger antibacterial and antioxidant activities of the synthesized complexes suggested them as a stronger antimicrobial agent. Our study advances the biological importance of palladium (II) amine complexes in the field of antimicrobial and antioxidant activities. PMID:27119023

  10. Advances in characterisation and biological activities of chitosan and chitosan oligosaccharides.

    PubMed

    Zou, Pan; Yang, Xin; Wang, Jing; Li, Yongfei; Yu, Hailong; Zhang, Yanxin; Liu, Guangyang

    2016-01-01

    Chitosan and chitosan oligosaccharides (COS) have been reported to possess various biomedical properties, including antimicrobial activities, immuno-enhancing effects, and anti-tumour activities. COS have attracted considerable interest due to their physicochemical properties, and potential applications in the food and pharmaceutical industries, especially in cancer therapies. This paper describes the preparation of COS and their physicochemical properties, and modification, which aids understanding of their biological activities. Based on the latest reports, several biological and anti-tumour activities of COS will be discussed. The proposed anti-tumour mechanisms of COS are summarised, to provide comprehensive insights into research on the molecular level. Finally, the potential applications and future development of the biopolymer will be discussed. PMID:26213092

  11. Chemical composition and biological activity of the essential oil of rhizome of Zingiber zerumbet (L.) smith

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Technical Abstract: The aim was designed to study the biological activity and chemical composition of essential oil of Zingiber zerumbet (L.) Smith. The essential oil extracted from the rhizome of the plant was analysed by gas chromatography-mass spectroscopy and its major components amounting t...

  12. Biologically active preparations with a stimulating and fungicidal effect based on peat

    SciTech Connect

    Naumova, G.V.; Kosonogova, L.V.; Zhmakova, N.A.

    1995-12-31

    Peat is a source of biologically active substances, most of which are humic acids. Peat also contains a broad range of elements including iron, iodine, copper, manganese, and cobalt. A wide range of these humic acids are utilized as growth stimulators. Studies of the preparation of the humic acids are described.

  13. Trouble in the Kitchen: A Problem-Based Activity in Human Biology

    ERIC Educational Resources Information Center

    Clovis, Christopher J.

    2005-01-01

    In Ontario, the secondary school science curriculum advocates the use of laboratory activities to reinforce specific scientific concepts and promotes the development of skills in scientific investigation and communication. Students in biology courses are often expected to identify unknown substances using standard tests, but rarely are these tests…

  14. Protonation Equilibria of Biologically Active Ligands in Mixed Aqueous Organic Solvents

    PubMed Central

    El-Sherif, Ahmed A.; Shoukry, Mohamed M.; Abd Elkarim, Abeer T.; Barakat, Mohammad H.

    2014-01-01

    The review is mainly concerned with the protonation equilibria of biologically active ligands like amino acids, peptides, DNA constituents, and amino acid esters in nonaqueous media. Equilibrium concentrations of proton-ligand formation as a function of pH were investigated. Also, thermodynamics associated with protonation equilibria were also discussed. PMID:25197267

  15. Active Learning "Not" Associated with Student Learning in a Random Sample of College Biology Courses

    ERIC Educational Resources Information Center

    Andrews, T. M.; Leonard, M. J.; Colgrove, C. A.; Kalinowski, S. T.

    2011-01-01

    Previous research has suggested that adding active learning to traditional college science lectures substantially improves student learning. However, this research predominantly studied courses taught by science education researchers, who are likely to have exceptional teaching expertise. The present study investigated introductory biology courses…

  16. neutron activation analysis using thermochromatography. III. analysis of samples of biological origin

    SciTech Connect

    Sattarov, G.; Davydov, A.V.; Khamatov, S.; Kist, A.A.

    1986-07-01

    The use of gas thermochromatography (GTC) in the radioactivation analysis of biological materials is discussed. A group separation of a number of highly volatile elements from sodium and bromine radionuclides has been achieved. The limit of detection of the elements by INAA and neutron activation analysis was estimated using GTC. The advantages of the procedure and the analytical parameters are discussed.

  17. Improving Enzyme Activity and Broadening Selectivity for Biological Desulfurization and Upgrading of Petroleum Feedstocks

    SciTech Connect

    Abhijeet P. Borole; Choo Y. Hamilton; Karen Miller; Brian Davison; Matthew Grossman; Robert Shong

    2003-05-12

    The objective of this project was to develop improved biocatalysts for desulfurization and upgrading of petroleum feedstocks. The goal was to improve the activity and broaden the selectivity of desulfurization enzymes using directed evolution as a tool as well as to explore the impact of ring-opening on biological desulfurization

  18. Learning Activity Package, Biology 102, (LAP) Studies 1, 3, and 4.

    ERIC Educational Resources Information Center

    Rhoden, Bruce

    Included are three Learning Activity Package (LAP) studies for use in high school biology: Everything has a Place (Grouping and the Diversity of Life), Energy Relations, and Reproduction. Each LAP contains a rationale for teaching the material included, student objectives (stated in behavioral terms), a list of related resources (books,…

  19. Astaxanthin: Sources, Extraction, Stability, Biological Activities and Its Commercial Applications—A Review

    PubMed Central

    Ambati, Ranga Rao; Siew Moi, Phang; Ravi, Sarada; Aswathanarayana, Ravishankar Gokare

    2014-01-01

    There is currently much interest in biological active compounds derived from natural resources, especially compounds that can efficiently act on molecular targets, which are involved in various diseases. Astaxanthin (3,3′-dihydroxy-β, β′-carotene-4,4′-dione) is a xanthophyll carotenoid, contained in Haematococcus pluvialis, Chlorella zofingiensis, Chlorococcum, and Phaffia rhodozyma. It accumulates up to 3.8% on the dry weight basis in H. pluvialis. Our recent published data on astaxanthin extraction, analysis, stability studies, and its biological activities results were added to this review paper. Based on our results and current literature, astaxanthin showed potential biological activity in in vitro and in vivo models. These studies emphasize the influence of astaxanthin and its beneficial effects on the metabolism in animals and humans. Bioavailability of astaxanthin in animals was enhanced after feeding Haematococcus biomass as a source of astaxanthin. Astaxanthin, used as a nutritional supplement, antioxidant and anticancer agent, prevents diabetes, cardiovascular diseases, and neurodegenerative disorders, and also stimulates immunization. Astaxanthin products are used for commercial applications in the dosage forms as tablets, capsules, syrups, oils, soft gels, creams, biomass and granulated powders. Astaxanthin patent applications are available in food, feed and nutraceutical applications. The current review provides up-to-date information on astaxanthin sources, extraction, analysis, stability, biological activities, health benefits and special attention paid to its commercial applications. PMID:24402174

  20. Case study: Comparison of biological active compounds in milk from organic and conventional dairy herds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Conflicting reports of the quantities of biologically active compounds present in milk from organic grass-fed and conventional herds show that more research is required, especially as these compounds are linked to human health benefits and can improve the health value consumers place on dairy produc...

  1. Preparation of Plant Samples for Phytochemical Research and the Study of Their Biological Activities

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Prior to investigating plant natural products for biologically active constituents, it is necessary to establish guidelines and procedures for carefully collecting, cataloging, and storing specimens. All field collections should begin with detailed records on location, which should include a list o...

  2. Moooving forward on determining biologically active compounds in milk and their impact on health

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recent studies have demonstrated that some of the lesser studied components in milk, known as biologically active compounds (BACs), may provide potential benefits to human health. The added health-value of raw milk and milk from organic and grass-fed herds is strongly debated because of limited, an...

  3. Metal-containing Complexes of Lactams, Imidazoles, and Benzimidazoles and Their Biological Activity

    NASA Astrophysics Data System (ADS)

    Kukalenko, S. S.; Bovykin, B. A.; Shestakova, S. I.; Omel'chenko, A. M.

    1985-07-01

    The results of the latest investigations of the problem of the synthesis of metal-containing complexes of lactams, imidazoles, and benzimidazoles, their structure, and their stability in solutions are surveyed. Some data on their biological activity (pesticide and pharmacological) and the mechanism of their physiological action are presented. The bibliography includes 190 references.

  4. Emergy Evaluations of the Global Biogeochemical Cycles of Six Biologically Active Elements and Two Compounds

    EPA Science Inventory

    Estimates of the emergy carried by the flows of biologically active elements (BAE) and compounds are needed to accurately evaluate the near and far field effects of anthropogenic wastes. The transformities and specific emergies of these elements and of their different chemical sp...

  5. A Journal-Club-Based Class that Promotes Active and Cooperative Learning of Biology

    ERIC Educational Resources Information Center

    Kitazono, Ana A.

    2010-01-01

    A journal-club-based class has been developed to promote active and cooperative learning and expose seniors in biochemistry and cellular molecular biology to recent research in the field. Besides giving oral presentations, students also write three papers: one discussing an article of their own choosing and two, discussing articles presented by…

  6. Astaxanthin: sources, extraction, stability, biological activities and its commercial applications--a review.

    PubMed

    Ambati, Ranga Rao; Phang, Siew Moi; Ravi, Sarada; Aswathanarayana, Ravishankar Gokare

    2014-01-01

    There is currently much interest in biological active compounds derived from natural resources, especially compounds that can efficiently act on molecular targets, which are involved in various diseases. Astaxanthin (3,3'-dihydroxy-β, β'-carotene-4,4'-dione) is a xanthophyll carotenoid, contained in Haematococcus pluvialis, Chlorella zofingiensis, Chlorococcum, and Phaffia rhodozyma. It accumulates up to 3.8% on the dry weight basis in H. pluvialis. Our recent published data on astaxanthin extraction, analysis, stability studies, and its biological activities results were added to this review paper. Based on our results and current literature, astaxanthin showed potential biological activity in in vitro and in vivo models. These studies emphasize the influence of astaxanthin and its beneficial effects on the metabolism in animals and humans. Bioavailability of astaxanthin in animals was enhanced after feeding Haematococcus biomass as a source of astaxanthin. Astaxanthin, used as a nutritional supplement, antioxidant and anticancer agent, prevents diabetes, cardiovascular diseases, and neurodegenerative disorders, and also stimulates immunization. Astaxanthin products are used for commercial applications in the dosage forms as tablets, capsules, syrups, oils, soft gels, creams, biomass and granulated powders. Astaxanthin patent applications are available in food, feed and nutraceutical applications. The current review provides up-to-date information on astaxanthin sources, extraction, analysis, stability, biological activities, health benefits and special attention paid to its commercial applications. PMID:24402174

  7. Science Attitude Change in Preservice Elementary Teachers during an Activity-Oriented Biology Course.

    ERIC Educational Resources Information Center

    Kramer, David C.

    1979-01-01

    Investigates the effect of an activity-oriented biology course on the science attitudes of preservice elementary teachers. Forty-nine students enrolled in this course during the winter and spring quarter of 1977 at St. Cloud State University, Minnesota participated in this study. (HM)

  8. ELECTROSTATIC POTENTIALS OF SOME DIBENZO-P-DIOXINS IN RELATION TO THEIR BIOLOGICAL ACTIVITIES (JOURNAL VERSION)

    EPA Science Inventory

    A computational analysis of the electrostatic potentials of eight halogenated dibenzo-p-dioxins has been carried out at the ab initio SCF STO-5G level. It focuses upon the relationships between these potentials and the biological activities of the molecules, including toxicity, a...

  9. Design, synthesis, and biological activity of oxime ether strobilurin derivatives containing indole moiety as novel fungicide.

    PubMed

    Xie, Ya-Qiang; Huang, Zi-Long; Yan, Hui-Dong; Li, Jun; Ye, Li-Yi; Che, Li-Ming; Tu, Song

    2015-06-01

    Twenty-one novel oxime ether strobilurins containing indole moiety, which employed an indole group to stabilize the E-styryl group in Enoxastrobin, were designed and synthesized. The biological assay indicated that most compounds exhibited potent fungicidal activities. The structure-activity relationship study demonstrated that the synthesized methyl 3-methoxypropenoate oxime ethers 7b-e exhibited remarkably high activities among all the synthesized oxime ether compounds 7. Moreover, the fungicidal activities of methyl α-(methoxyimino)benzeneacetate oxime ethers compounds 7f-i and N-methoxy-carbamic acid methyl esters compounds 7j-m showed significant differences compared to the corresponding products of ammonolysis. PMID:25346294

  10. Activities of microorganisms and enzymes in water-restricted environments: biological activities in aqueous compartments at micron scale

    NASA Astrophysics Data System (ADS)

    Hoppert, Michael; Mlejnek, Klaus; Seiffert, Beatrix; Mayer, Frank

    1997-07-01

    In water-in-oil microemulsions, microdroplets of water, surrounded by a layer of surfactant molecules (reversed micelles), are dispersed in an organic solvent. Various microorganisms (unicellular algae and cyanobacteria) and isolated enzymes were dispersed in microemulsions without loss of biological activity. Each biological system needed a defined quantity of water in the microemulsion for maximum activity. Under optimum conditions, microbial enzymes for various sources (hydrogenases, dehydrogenases) exhibited, besides ten-fold increase in specific activity, a temperature optimum up to 16 degree(s)C higher as compared to aqueous solutions. These experimental findings, together with theoretical considerations, imply that water structure inside reversed micelles is very different from free water, but similar to water in narrow compartments with polar or ionic surfaces. These compartments may represent a model system for environments, where (liquid) water is not available in bulk amounts, but embedded in an anhydrous matrix.

  11. Effect of spacer length and type on the biological activity of peptide-polysaccharide matrices.

    PubMed

    Kumai, Jun; Hozumi, Kentaro; Yamada, Yuji; Katagiri, Fumihiko; Kikkawa, Yamato; Nomizu, Motoyoshi

    2016-11-01

    Peptide-polysaccharide matrices can mimic extracellular matrix structure and function and are useful for tissue and cell engineering. The spacer between the peptide and the polysaccharide is important for both peptide conformation and the interaction between the peptide and receptors. Here, the effect of a spacer on the biological activity of peptide-polysaccharide matrices using various lengths of spacers consisting of glycine, β-alanine, and ε-aminocaproic acid has been examined. Active laminin-derived peptides, including a syndecan-binding peptide (AG73: RKRLQVQLSIRT), an integrin αvβ3-binding peptide (A99a: ALRGDN), and an integrin α6β1-binding peptide (A2G10: SYWYRIEASRTG), were used as the peptide ligands and chitosan was used as a polysaccharide matrix. The spacers did not influence the biological activity of the AG73-chitosan matrix. In contrast, the integrin-binding peptide-chitosan matrices showed spacer-dependent activity. Hydrophobic spacers enhanced the cell attachment activity of the A99a-chitosan matrix. A four-glycine spacer showed the strongest effect for the biological activity of the A2G10-chitosan matrix. These results suggested that spacer-optimization for each peptide is important for designing effective peptide-polysaccharide matrices. © 2015 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 106: 512-520, 2016. PMID:26588050

  12. Biologically active warm-core anticyclonic eddies in the marginal seas of the western Pacific Ocean

    NASA Astrophysics Data System (ADS)

    Chen, Yuh-ling Lee; Chen, Houng-Yung; Jan, Sen; Lin, Yen-Huei; Kuo, Tien-Hsia; Hung, Jia-Jang

    2015-12-01

    Our investigations in the northern South China Sea (SCS) have revealed warm-core anticyclonic eddies that had a depressed pycnocline and a high biological productivity and phytoplankton abundance. With an elliptical shape of 420-430 km in major axis and 240-260 km in minor axis, these eddies were formed in the winter as the Kuroshio Current intruded through the Luzon Strait into the SCS under the prevailing northeast monsoon. They were characterized by a deep mixed layer up to 140-180 m, in which nitrate was relatively abundant. Although chlorophyll a concentration per volume of seawater was not always higher inside than outside the eddies, water-column (0-200 m) integrated chlorophyll a concentration and abundances of Synechococcus, coccolithophores, and diatoms were higher inside than outside the eddies. Primary productivity and nitrate-uptake new production inside the eddies were higher than or equal to those outside the eddies. Unlike the mode-water anticyclonic eddy that is biologically productive with a domed shallow seasonal pycnocline, the eddies we investigated had high surface temperatures and depressed pycnoclines in the upper water column. Possible explanations for these biological aspects were that the eddies were at their decaying stage, the eddies re-incorporated intermittently with an intruding Kuroshio branch, or the passage of the prevalent high amplitude internal tides introduced nutrients to the eddies. Frequent occurrences of eddies in oceanic regimes, especially cold eddies, are associated with high biological activity. Some warm eddies, such as these investigated in the present study, also have high biological activities, indicating that more rigorous in situ studies relating to eddy biological activity are needed in ocean regimes such as the SCS, where a half of the eddies are warm eddies.

  13. Two Dawson-templated three-dimensional metal-organic frameworks based on oxalate-bridged binuclear cobalt(II)/Nickel(II) SBUs and Bpy linkers.

    PubMed

    Zhao, Xinyu; Liang, Dadong; Liu, Shuxia; Sun, Chunyan; Cao, Ruige; Gao, Chaoying; Ren, Yuanhang; Su, Zhongmin

    2008-08-18

    The Dawson anion P 2W 18O 62 (6-) has been used as a noncoordinating polyoxoanion template for the construction of two metal-organic frameworks, namely, [M 2(bpy) 3(H 2O) 2(ox)][P 2W 18O 62]2(H 2-bpy). nH 2O (M = Co(II), n = 3 ( 1); M = Ni(II), n = 2 ( 2)) (bpy = 4,4'-bipyridine; ox = C 2O 4 (2-)). Single-crystal X-ray analysis reveals that both of the structures exhibit 3D host frameworks constructed from the oxalate-bridged binuclear superoctahedron secondary building units (SBUs) and bpy linkers and the voids of which are occupied by Dawson anions, guest bpy, and water molecules. Magnetic studies reveal that there are antiferromagnetic exchange interactions among the transition-metal centers in compounds 1 and 2. Furthermore, a compound 1-modified carbon paste electrode ( 1-CPE) displays good electrocatalytic activity toward the reduction of nitrite. PMID:18620386

  14. Novel binuclear μ-oxo diruthenium complexes combined with ibuprofen and ketoprofen: Interaction with relevant target biomolecules and anti-allergic potential.

    PubMed

    Seuanes, Gabriela Campos; Moreira, Mariete Barbosa; Petta, Tânia; de Moraes Del Lama, Maria Perpétua Freire; de Moraes, Luiz Alberto Beraldo; de Oliveira, Anderson Rodrigo Moraes; Naal, Rose Mary Zumstein Georgetto; Nikolaou, Sofia

    2015-12-01

    This work presents the synthesis and characterization of two novel binuclear ruthenium compounds of general formula [Ru2O(carb)2(py)6](PF6)2, where py=pyridine and carb are the non-steroidal anti-inflammatory drugs ibuprofen (1) and ketoprofen (2). Both complexes were characterized by ESI-MS/MS spectrometry. The fragmentation patterns, which confirm the proposed structures, are presented. Besides that, compounds 1 and 2 present the charge transfer transitions within 325-330nm; and the intra-core transitions around 585nm, which is the typical spectra profile for [Ru2O] analogues. This suggests the carboxylate bridge has little influence in their electronic structure. The effects of the diruthenium complexes on Ig-E mediated mast cell activation were evaluated by measuring the enzyme β-hexosaminidase released by mast cells stimulated by antigen. The inhibitory potential of the ketoprofen complex against mast cell stimulation suggests its promising application as a therapeutic agent for treating or preventing IgE-mediated allergic diseases. In addition, in vitro metabolism assays had shown that the ibuprofen complex is metabolized by the cytochrome P450 enzymes. PMID:26298864

  15. Metal-organic frameworks for the storage and delivery of biologically active hydrogen sulfide

    SciTech Connect

    Allan, Phoebe K; Wheatley, Paul S; Aldous, David; Mohideen, M Infas; Tang, Chiu; Hriljac, Joseph A; Megson, Ian L; Chapman, Karena W; De Weireld, Guy; Vaesen, Sebastian; Morris, Russell E

    2012-04-02

    Hydrogen sulfide is an extremely toxic gas that is also of great interest for biological applications when delivered in the correct amount and at the desired rate. Here we show that the highly porous metal-organic frameworks with the CPO-27 structure can bind the hydrogen sulfide relatively strongly, allowing the storage of the gas for at least several months. Delivered gas is biologically active in preliminary vasodilation studies of porcine arteries, and the structure of the hydrogen sulfide molecules inside the framework has been elucidated using a combination of powder X-ray diffraction and pair distribution function analysis.

  16. The biological activities and chemical composition of Pereskia species (Cactaceae)--a review.

    PubMed

    Pinto, Nícolas de Castro Campos; Scio, Elita

    2014-09-01

    The exploration of nature as a source of sustainable, novel bioactive substances continues to grow as natural products play a significant role in the search for new therapeutic and agricultural agents. In this context, plants of the genus Pereskia (Cactaceae) have been studied for their biological activities, and are evolving as an interesting subject in the search for new, bioactive compounds. These species are commonly used as human foodstuffs and in traditional medicine to treat a variety of diseases. This review focuses on the bioactivity and chemical composition of the genus Pereskia, and aims to stimulate further studies on the chemistry and biological potential of the genus. PMID:24862084

  17. Synthesis, structural characterization and biological activity of two diastereomeric JA-Ile macrolactones.

    PubMed

    Jimenez-Aleman, Guillermo H; Machado, Ricardo A R; Görls, Helmar; Baldwin, Ian T; Boland, Wilhelm

    2015-06-01

    Jasmonates are phytohormones involved in a wide range of plant processes, including growth, development, senescence, and defense. Jasmonoyl-L-isoleucine (JA-Ile, 2), an amino acid conjugate of jasmonic acid (JA, 1), has been identified as a bioactive endogenous jasmonate. However, JA-Ile (2) analogues trigger different responses in the plant. ω-Hydroxylation of the pentenyl side chain leads to the inactive 12-OH-JA-Ile (3) acting as a “stop” signal. On the other hand, a lactone derivative of 12-OH-JA (5) (jasmine ketolactone, JKL) occurs in nature, although with no known biological function. Inspired by the chemical structure of JKL (6) and in order to further explore the potential biological activities of 12-modified JA-Ile derivatives, we synthesized two macrolactones (JA-Ile-lactones (4a) and (4b)) derived from 12-OH-JA-Ile (3). The biological activity of (4a) and (4b) was tested for their ability to elicit nicotine production, a well-known jasmonate dependent secondary metabolite. Both macrolactones showed strong biological activity, inducing nicotine accumulation to a similar extent as methyl jasmonate does in Nicotiana attenuata leaves. Surprisingly, the highest nicotine contents were found in plants treated with the JA-Ile-lactone (4b), which has (3S,7S) configuration at the cyclopentanone not known from natural jasmonates. Macrolactone (4a) is a valuable standard to explore for its occurrence in nature. PMID:25806705

  18. Elucidation of the Covalent and Tertiary Structures of Biologically Active Ts3 Toxin.

    PubMed

    Dang, Bobo; Kubota, Tomoya; Mandal, Kalyaneswar; Correa, Ana M; Bezanilla, Francisco; Kent, Stephen B H

    2016-07-18

    Ts3 is an alpha scorpion toxin from the venom of the Brazilian scorpion Tityus serrulatus. Ts3 binds to the domain IV voltage sensor of voltage-gated sodium channels (Nav ) and slows down their fast inactivation. The covalent structure of the Ts3 toxin is uncertain, and the structure of the folded protein molecule is unknown. Herein, we report the total chemical synthesis of four candidate Ts3 toxin protein molecules and the results of structure-activity studies that enabled us to establish the covalent structure of biologically active Ts3 toxin. We also report the synthesis of the mirror image form of the Ts3 protein molecule, and the use of racemic protein crystallography to determine the folded (tertiary) structure of biologically active Ts3 toxin by X-ray diffraction. PMID:27244051

  19. In vitro and in vivo biological activities of anthocyanins from Nitraria tangutorun Bobr. fruits.

    PubMed

    Ma, Tao; Hu, Na; Ding, Chenxi; Zhang, Qiulong; Li, Wencong; Suo, Yourui; Wang, Honglun; Bai, Bo; Ding, Chenxu

    2016-03-01

    Anthocyanins are the main compounds in Nitraria tangutorun Bobr. The enrichment and purification of anthocyanins on macroporous resins were investigated. Regarding anthocyanin purification, static adsorption and desorption were studied. The optimal experimental conditions were the following: resin type: X-5; static adsorption time: 6h; desorption solution: ethanol-water-HCl (80:19:1, V/V/V; pH 1); desorption time: 40min. Furthermore, the in vitro and in vivo biological activities of the anthocyanins were evaluated. The anthocyanins showed ideal scavenging effects on free radicals in vitro, especially on 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl free radical (OH). In the animal experiment, blood lipid metabolism of hyperlipidemia rats was regulated by anthocyanin contents. The superoxide dismutase (SOD) activity and the total antioxidant capacity (TAC) of hyperlipidemia rats were also improved by anthocyanins. These results showed that anthocyanins from N. tangutorun Bobr. fruits had potential biological activities in vivo as well as in vitro. PMID:26471558

  20. Evaluating the biological activity of oil-polluted soils using a complex index

    NASA Astrophysics Data System (ADS)

    Kabirov, R. R.; Kireeva, N. A.; Kabirov, T. R.; Dubovik, I. Ye.; Yakupova, A. B.; Safiullina, L. M.

    2012-02-01

    A complex index characterizing the biological activity of soils (BAS) is suggested. It is based on an estimate of the level of activity of catalase; the number of heterotrophic and hydrocarbon oxidizing microorganisms, microscopic fungi, algae, and cyanobacteria; and the degree of development of higher plants and insects in the studied soil. The data on using the BAS coefficient for evaluating the efficiency of rehabilitation measures for oil-polluted soils are given. Such measures included introducing the following biological preparations: Lenoil based on a natural consortium of microorganisms Bacillus brevis and Arthrobacter sp.; the Azolen biofertilizer with complex action based on Azotobacter vinelandii; the Belvitamil biopreparation, which is the active silt of pulp and paper production; and a ready-mixed industrial association of aerobic and anaerobic microorganisms that contains hydrocarbon oxidizing microorganisms of the Arthrobacter, Bacillus, Candida, Desulfovibrio, and Pseudomonas genera.

  1. Biological activities of crude extracts and chemical constituents of Bael, Aegle marmelos (L.) Corr.

    PubMed

    Maity, Pallab; Hansda, Dhananjay; Bandyopadhyay, Uday; Mishra, Dipak Kumar

    2009-11-01

    Bael (Aegle marmelos (L.) Corr.) is an important medicinal plant of India. Leaves, fruits, stem and roots of A. marmelos have been used in ethno medicine to exploit its' medicinal properties including astringent, antidiarrheal antidysenteric, demulcent, antipyretic and anti-inflammatory activities. Compounds purified from bael have been proven to be biologically active against several major diseases including cancer, diabetes and cardiovascular diseases. Preclinical studies indicate the therapeutic potential of crude extracts of A. marmelos in the treatment of many microbial diseases, diabetes and gastric ulcer. This review covers the biological activities of some isolated chemical constituents of A. marmelos and preclinical studies on some crude extracts and pure compounds to explore novel bioactive compounds for therapeutic application. PMID:20099458

  2. UME6, a negative regulator of meiosis in Saccharomyces cerevisiae, contains a C-terminal Zn2Cys6 binuclear cluster that binds the URS1 DNA sequence in a zinc-dependent manner.

    PubMed Central

    Anderson, S. F.; Steber, C. M.; Esposito, R. E.; Coleman, J. E.

    1995-01-01

    UME6 is a protein of 836 amino acids from Saccharomyces cerevisiae that acts as a repressor and activator of several early meiotic genes. UME6 contains, near the C-terminus, the amino acid sequence-771C-X2-C-X6-C-X6-C-X2-C-X6-C-, in which the spacings of the six Cys residues are identical to those found in 39 N-terminal Cys-rich DNA binding subdomains of fungal transcription factors. This sequence has been shown in GAL4 and other proteins to form a zinc binuclear cluster. In spite of the different location, the C-rich sequence, cloned and over-produced within the last 111 amino acid residues of UME6, UME6(111), forms a binuclear cluster and exhibits a Zn-dependent binding to the URS1 DNA sequence. The latter, TAGCCGCCGA, is required for the repression or activation of meiosis-specific genes by UME6. UME6(111) contains 1.8 +/- 0.4 mol Zn/mol protein and the Zn can be exchanged for Cd to yield a protein containing 1.9 +/- 0.1 mol Cd/mol protein. At 5 degrees C, 113Cd2UME6(111) shows two 113Cd NMR signals, with chemical shifts of 699 and 689 ppm, similar to those observed for 113Cd2GAL4(149). The magnitude of these chemical shifts suggests that each 113Cd nucleus is coordinated to four -S- ligands, compatible with a 113Cd2 cluster structure in which two thiolates from bridging ligands. The entire UME6 gene has been cloned and overexpressed and binds more tightly to the URS1 sequence than the zinc binuclear cluster domain alone. DNase I footprints of UME6 on URS1-containing DNA show that the protein protects the phosphodiesters of the 5'-CCGCCG-3' region within the URS1 sequence. PMID:8528081

  3. Isolation and characterization of biologically active venom protein from sea snake Enhydrina schistosa.

    PubMed

    Damotharan, Palani; Veeruraj, Anguchamy; Arumugam, Muthuvel; Balasubramanian, Thangavel

    2015-03-01

    The present study is designed to investigate the isolation and characterization of biological and biochemical active venom protein from sea snake, Enhydrina schistosa. The highest purification peaks in ion-exchange chromatography on DEAE-cellulose column were obtained for fraction numbers 39-49 when eluted with 0.35-0.45 M NaCl. Eighty per cent purity was obtained in the final stage of purification, and a single protein band of about 44 kDa was visualized in SDS-polyacrylamide gel under reducing condition. Purified venom protein expressed as haemolytic, cytotoxicity and proteolytic activities with lethal concentration (LC50 ) at 2.0 μg/mL. Venom protein exhibits enzymatic activity and hydrolyzed casein and gelatin. Gelatinolytic activity was optimal at pH 5-9. In conclusion, the present results suggested that the sea snake venom might be feasible sources for biologically active substances. Thus, this low molecular weight component of the venom protein could be used in potentially serve biological and pharmaceutical aspects. PMID:25504782

  4. Tuning the Biological Activity Profile of Antibacterial Polymers via Subunit Substitution Pattern

    PubMed Central

    2015-01-01

    Binary nylon-3 copolymers containing cationic and hydrophobic subunits can mimic the biological properties of host-defense peptides, but relationships between composition and activity are not yet well understood for these materials. Hydrophobic subunits in previously studied examples have been limited mostly to cycloalkane-derived structures, with cyclohexyl proving to be particularly promising. The present study evaluates alternative hydrophobic subunits that are isomeric or nearly isomeric with the cyclohexyl example; each has four sp3 carbons in the side chains. The results show that varying the substitution pattern of the hydrophobic subunit leads to relatively small changes in antibacterial activity but causes significant changes in hemolytic activity. We hypothesize that these differences in biological activity profile arise, at least in part, from variations among the conformational propensities of the hydrophobic subunits. The α,α,β,β-tetramethyl unit is optimal among the subunits we have examined, providing copolymers with potent antibacterial activity and excellent prokaryote vs eukaryote selectivity. Bacteria do not readily develop resistance to the new antibacterial nylon-3 copolymers. These findings suggest that variation in subunit conformational properties could be generally valuable in the development of synthetic polymers for biological applications. PMID:24601599

  5. Water at Biological Phase Boundaries: Its Role in Interfacial Activation of Enzymes and Metabolic Pathways.

    PubMed

    Damodaran, Srinivasan

    2015-01-01

    Many life-sustaining activities in living cells occur at the membrane-water interface. The pertinent questions that we need to ask are, what are the evolutionary reasons in biology for choosing the membrane-water interface as the site for performing and/or controlling crucial biological reactions, and what is the key physical principle that is very singular to the membrane-water interface that biology exploits for regulating metabolic processes in cells? In this chapter, a hypothesis is developed, which espouses that cells control activities of membrane-bound enzymes through manipulation of the thermodynamic activity of water in the lipid-water interfacial region. The hypothesis is based on the fact that the surface pressure of a lipid monolayer is a direct measure of the thermodynamic activity of water at the lipid-water interface. Accordingly, the surface pressure-dependent activation or inactivation of interfacial enzymes is directly related to changes in the thermodynamic activity of interfacial water. Extension of this argument suggests that cells may manipulate conformations (and activities) of membrane-bound enzymes by manipulating the (re)activity of interfacial water at various locations in the membrane by localized compression or expansion of the interface. In this respect, cells may use the membrane-bound hormone receptors, lipid phase transition, and local variations in membrane lipid composition as effectors of local compression and/or expansion of membrane, and thereby local water activity. Several experimental data in the literature will be reexamined in the light of this hypothesis. PMID:26438268

  6. Physical Activity, Physical Performance, and Biological Markers of Health among Sedentary Older Latinos.

    PubMed

    Moreno, Gerardo; Mangione, Carol M; Wang, Pin-Chieh; Trejo, Laura; Butch, Anthony; Tseng, Chi-Hong; Sarkisian, Catherine A

    2014-01-01

    Background. Physical activity is associated with better physical health, possibly by changing biological markers of health such as waist circumference and inflammation, but these relationships are unclear and even less understood among older Latinos-a group with high rates of sedentary lifestyle. Methods. Participants were 120 sedentary older Latino adults from senior centers. Community-partnered research methods were used to recruit participants. Inflammatory (C-reactive protein) and metabolic markers of health (waist circumference, HDL-cholesterol, triglycerides, insulin, and glucose), physical activity (Yale physical activity survey), and physical performance (short physical performance NIA battery) were measured at baseline and 6-month followup. Results. Eighty percent of the sample was female. In final adjusted cross-sectional models, better physical activity indices were associated with faster gait speed (P < 0.05). In adjusted longitudinal analyses, change in self-reported physical activity level correlated inversely with change in CRP (β = -0.05; P = 0.03) and change in waist circumference (β = -0.16; P = 0.02). Biological markers of health did not mediate the relationship between physical activity and physical performance. Conclusion. In this community-partnered study, higher physical activity was associated with better physical performance in cross-sectional analyses. In longitudinal analysis, increased physical activity was associated with improvements in some metabolic and inflammatory markers of health. PMID:25136359

  7. Enhancement of near-infrared luminescence of ytterbium in triple-stranded binuclear helicates.

    PubMed

    Li, Bing; Li, Hongfeng; Chen, Peng; Sun, Wenbin; Wang, Cheng; Gao, Ting; Yan, Pengfei

    2015-11-11

    A bis-β-diketone, bis(4,4,4-trifluoro-1,3-dioxobutyl)(2,2'-bithienyl) (BTT), which can be looked upon as coupling of two mono-β-diketones (2-thenoyltrifluoroacetone, TTA) at the 5,5'-position of thiophene ring, has been designed for exploring the advantages of binuclear helical structure in sensitizing the lanthanide NIR luminescence. The Yb(iii) ion was selected as the luminescent center, and its corresponding mono-β-diketone complex Yb(TTA)3(DMSO) () and bis-β-diketone complex Yb2(BTT)3(DMSO)4 () were synthesized and isolated. X-ray crystallographical analysis reveals that the bis-β-diketone complex Yb2(BTT)3(DMSO)4 adopts a triple-stranded dinuclear structure, in which the two Yb(iii) ions are helically wrapped by three ligands, and each Yb(iii) ion is eight-coordinated by six oxygen atoms from three ligands and two oxygen atoms from the coordinated DMSO molecules. Whereas, the mono-β-diketone complex Yb(TTA)3(DMSO) is a mononuclear structure, the central Yb(iii) ion is coordinated by seven oxygen atoms from three ligands and a DMSO molecule. The photophysical properties related to the electronic transition are characterized by the absorbance spectra, the emission spectra, the emission quantum yields, the emission lifetimes, and the radiative (kr) and nonradiative rate constants (knr). The luminescence quantum yield experiment reveals that the dinuclear complex has about 10 times luminescence enhancement compared with the mononuclear complex. This enhancement mainly benefits from its helical structure, which effectively depresses the nonradiative transition caused by high-energy oscillators in ligands, and the part-encapsulated structure decreases the probability of solvents entering the metal centers. PMID:26513394

  8. Vibrational relaxation and intersystem crossing of binuclear metal complexes in solution.

    PubMed

    van der Veen, Renske M; Cannizzo, Andrea; van Mourik, Frank; Vlček, Antonín; Chergui, Majed

    2011-01-19

    The ultrafast vibrational-electronic relaxation upon excitation into the singlet (1)A(2u) (dσ*→pσ) excited state of the d(8)-d(8) binuclear complex [Pt(2)(P(2)O(5)H(2))(4)](4-) has been investigated in different solvents by femtosecond polychromatic fluorescence up-conversion and femtosecond broadband transient absorption (TA) spectroscopy. Both sets of data exhibit clear signatures of vibrational relaxation and wave packet oscillations of the Pt-Pt stretch vibration in the (1)A(2u) state with a period of 224 fs, that decay on a 1-2 ps time scale, and of intersystem crossing (ISC) into the (3)A(2u) state. The vibrational relaxation and ISC times exhibit a pronounced solvent dependence. We also extract from the TA measurements the spectral distribution of the wave packet at a given delay time, which reflects the distribution of Pt-Pt bond distances as a function of time, i.e., the structural dynamics of the system. We clearly establish the vibrational relaxation and coherence decay processes, and we demonstrate that PtPOP represents a clear example of a harmonic oscillator that does not comply with the optical Bloch description due to very efficient coherence transfer between vibronic levels. We conclude that a direct Pt-solvent energy dissipation channel accounts for the vibrational cooling in the singlet state. ISC from the (1)A(2u) to the (3)A(2u) state is induced by spin-vibronic coupling with a higher-lying triplet state and/or (transient) symmetry breaking in the (1)A(2u) excited state. The particular structure, energetics, and symmetry of the molecule play a decisive role in determining the relatively slow rate of ISC, despite the large spin-orbit coupling strength of the Pt atoms. PMID:21162574

  9. The DNA binding domain of GAL4 forms a binuclear metal ion complex.

    PubMed

    Pan, T; Coleman, J E

    1990-03-27

    The transcription factor GAL4 from Saccharomyces cerevisiae requires Zn(II) or Cd(II) for specific recognition of the UASG sequence (Pan & Coleman, 1989). An N-terminal fragment consisting of the first 63 amino acid residues of GAL4 [GAL4(63)] has been obtained by partial tryptic proteolysis of a cloned and overproduced N-terminal domain of 149 residues, GAL(149). We show that GAL4(63) contains the minimal GAL4 DNA binding domain. GAL4(63) binds tightly 1-2 mol of Zn(II) or 2 mol of Cd(II). 113Cd NMR of 113Cd(II)-substituted GAL4(63) reveals structural identity between the metal binding domains of GAL4(63) and that of the larger precursor GAL4(149). 113Cd(II) can be substituted for the Zn(II) in GAL4(63), and two 113Cd NMR signals are observed at 706 and 669 ppm, both suggesting coordination of 113Cd(II) to three or four -S- ligands. With the exception of the N-terminal methionine, the only sulfur-containing residues are the six highly conserved cysteines. High-resolution 1H NMR of Zn(II)-GAL4(63) and Cd(II)-GAL4(63) show the two proteins to have almost identical conformations and to be present as monomers in solutions up to millimolar concentration. This leads us to postulate that GAL4 does not possess a TFIIIA-like "Zn-finger" but forms a binuclear metal cluster involving all six cysteines in a "cloverleaf"-like array. GAL4(63) contains about 60% alpha-helix, estimated from circular dichroism. Removal of the native Zn(II) causes substantial unfolding of the secondary structure. Unlike GAL4(149), the resultant apoprotein is not induced to refold by readdition of Zn(II) at low concentrations. PMID:2186803

  10. High-performance photoelectrochemical cells based on a binuclear ruthenium catalyst for visible-light-driven water oxidation.

    PubMed

    Zhang, Linlin; Gao, Yan; Ding, Xin; Yu, Ze; Sun, Licheng

    2014-10-01

    Two photoanodes based on a binuclear (2) and a mononuclear ruthenium (3) water oxidation catalysts were assembled in combination with a molecular photosensitizer (1) by using a co-adsorption method. The anodes were used in dye-sensitized photoelectrochemical cells (DS-PECs) for visible-light-driven water splitting. A DS-PEC device using TiO2 (1+2) as working electrode (WE) exhibits better performance than TiO2 (1+3) as WE in light-driven water splitting. Detailed photoelectrochemical studies on these DS-PEC devices are discussed. PMID:25139154

  11. Synthesis and biological evaluation of arctigenin ester and ether derivatives as activators of AMPK.

    PubMed

    Shen, Sida; Zhuang, Jingjing; Chen, Yijia; Lei, Min; Chen, Jing; Shen, Xu; Hu, Lihong

    2013-07-01

    A series of new arctigenin and 9-deoxy-arctigenin derivatives bearing different ester and ether side chains at the phenolic hydroxyl positions are designed, synthesized, and evaluated for activating AMPK potency in L6 myoblasts. Initial biological evaluation indicates that some alkyl ester and phenethyl ether arctigenin derivatives display potential activities in AMPK phosphorylation improvement. Further structure-activity relationship analysis shows that arctigenin ester derivatives 3a, 3h and 9-deoxy-arctigenin phenethyl ether derivatives 6a, 6c, 6d activate AMPK more potently than arctigenin. Moreover, the 2-(3,4-dimethoxyphenyl)ethyl ether moiety of 6c has been demonstrated as a potential functional group to improve the effect of AMPK phosphorylation. The structural optimization of arctigenin leads to the identification of 6c as a promising lead compound that exhibits excellent activity in AMPK activation. PMID:23673223

  12. Biological activities of extracts from Chenopodium ambrosioides Lineu and Kielmeyera neglecta Saddi

    PubMed Central

    2012-01-01

    Background Chenopodium ambrosioides and Kielmeyera neglecta are plants traditionally used in Brazil to treat various infectious diseases. The study of the biological activities of these plants is of great importance for the detection of biologically active compounds. Methods Extracts from these plants were extracted with hexane (Hex), dichloromethane (DCM), ethyl acetate (EtOAc) and ethanol (EtOH) and assessed for their antimicrobial properties, bioactivity against Artemia salina Leach and antifungal action on the cell wall of Neurospora crassa. Results Extracts from C. ambrosioides (Hex, DCM and EtOH) and K. neglecta (EtOAc and EtOH) showed high bioactivity against A. salina (LD50 < 1000 μg/mL), which might be associated with cytotoxic activity against cancer cells. C. ambrosioides Hex and DCM showed specific activity against yeasts, highlighting the activity of hexanic extract against Candida krusei (MIC = 100 μg/mL). By comparing the inhibitory concentration of 50% growth (IC 50%) with the growth control, extracts from K. neglecta EtOAc and EtOH have shown activities against multidrug-resistant bacteria (Enterococcus faecalis ATCC 51299 and Staphylococcus aureus ATCC 43300), with IC 50% of 12.5 μg/mL The assay carried out on N. crassa allowed defining that extracts with antifungal activity do not have action through inhibition of cell wall synthesis. Conclusions Generally speaking, extracts from C. ambrosioides and K. neglecta showed biological activities that have made the search for bioactive substances in these plants more attractive, illustrating the success of their use in the Brazilian folk medicine. PMID:22839690

  13. [Evaluation of the total biological activity and allergenic composition of allergenic extracts].

    PubMed

    Lombardero, M; González, R; Duffort, O; Juan, F; Ayuso, R; Ventas, P; Cortés, C; Carreira, J

    1986-01-01

    In the present study, a complete procedure is presented in order to standardize allergenic extracts, the meaning of which is the measurement of the total allergenic activity and the determination of the allergenic composition. The measurement of the biological activity comprises 2 steps: Preparation of Reference Extracts and determination of their "in vivo" activity. Evaluation of the total allergenic activity of extracts for clinical use. Reference extracts were prepared from the main allergens and their "in vivo" biological activity was determined by a quantitative skin prick test in a sample of at least 30 allergic patients. By definition, the protein concentration of Reference Extract that produces, in the allergic population, a geometric mean wheal of 75 mm.2 has an activity of 100 biological units (BUs). The determination of the biological activity of a problem extract is made by RAST inhibition. The sample is compared with the corresponding Reference Extract by this technique and, from this comparison, it is possible to quantify the activity of the problem extract in biologic units (BUs) with clinical significance. Likewise, different techniques have been used to determine the allergenic composition of extracts. These techniques comprise 2 steps: Separation of the components of the extract. Identification of the components that bind specific human IgE. The separation of the components of the extract has been carried out by isoelectric focusing (IEF) and electrophoresis in the presence of sodium dodecyl sulphate (SDS-PAGE). In order to identify the allergenic components, an immunoblotting technique has been employed. The separated components in the IEF gel or SDS-PAGE gel are transferred to a nitrocellulose sheet and later on, this membrane is overlaid with a serum pool from allergic patients and a mouse monoclonal anti-human IgE, labelled with 125I. Finally, the autoradiography of the nitrocellulose membrane is obtained. In this way it is possible to compare

  14. Oxidative mechanisms of biological activity of low-intensity radiofrequency radiation.

    PubMed

    Yakymenko, Igor; Tsybulin, Olexandr; Sidorik, Evgeniy; Henshel, Diane; Kyrylenko, Olga; Kyrylenko, Sergiy

    2016-01-01

    This review aims to cover experimental data on oxidative effects of low-intensity radiofrequency radiation (RFR) in living cells. Analysis of the currently available peer-reviewed scientific literature reveals molecular effects induced by low-intensity RFR in living cells; this includes significant activation of key pathways generating reactive oxygen species (ROS), activation of peroxidation, oxidative damage of DNA and changes in the activity of antioxidant enzymes. It indicates that among 100 currently available peer-reviewed studies dealing with oxidative effects of low-intensity RFR, in general, 93 confirmed that RFR induces oxidative effects in biological systems. A wide pathogenic potential of the induced ROS and their involvement in cell signaling pathways explains a range of biological/health effects of low-intensity RFR, which include both cancer and non-cancer pathologies. In conclusion, our analysis demonstrates that low-intensity RFR is an expressive oxidative agent for living cells with a high pathogenic potential and that the oxidative stress induced by RFR exposure should be recognized as one of the primary mechanisms of the biological activity of this kind of radiation. PMID:26151230

  15. Biological Activity of Peanut (Arachis hypogaea) Phytoalexins and Selected Natural and Synthetic Stilbenoids

    PubMed Central

    SOBOLEV, VICTOR S.; KHAN, SHABANA I.; TABANCA, NURHAYAT; WEDGE, DAVID E.; MANLY, SUSAN P.; CUTLER, STEPHEN J.; COY, MONIQUE R.; BECNEL, JAMES J.; NEFF, SCOTT A.; GLOER, JAMES B.

    2011-01-01

    The peanut plant (Arachis hypogaea L.), when infected by a microbial pathogen, is capable of producing stilbene-derived compounds that are considered antifungal phytoalexins. In addition, the potential health benefits of other stilbenoids from peanuts, including resveratrol and pterostilbene, have been acknowledged by several investigators. Despite considerable progress in peanut research, relatively little is known about the biological activity of the stilbenoid phytoalexins. This study investigated the activities of some of these compounds in a broad spectrum of biological assays. Since peanut stilbenoids appear to play roles in plant defense mechanisms, they were evaluated for their effects on economically important plant pathogenic fungi of the genera Colletotrichum, Botrytis, Fusarium, and Phomopsis. We further investigated these peanut phytoalexins, together with some related natural and synthetic stilbenoids (a total of 24 compounds) in a panel of bioassays to determine their anti-inflammatory, cytotoxic, and antioxidant activities in mammalian cells. Several of these compounds were also evaluated as mammalian opioid receptor competitive antagonists. Assays for adult mosquito and larvae toxicity were also performed. The results of these studies reveal that peanut stilbenoids, as well as related natural and synthetic stilbene derivatives, display a diverse range of biological activities. PMID:21314127

  16. Generation of structurally novel short carotenoids and study of their biological activity

    PubMed Central

    Kim, Se H.; Kim, Moon S.; Lee, Bun Y.; Lee, Pyung C.

    2016-01-01

    Recent research interest in phytochemicals has consistently driven the efforts in the metabolic engineering field toward microbial production of various carotenoids. In spite of systematic studies, the possibility of using C30 carotenoids as biologically functional compounds has not been explored thus far. Here, we generated 13 novel structures of C30 carotenoids and one C35 carotenoid, including acyclic, monocyclic, and bicyclic structures, through directed evolution and combinatorial biosynthesis, in Escherichia coli. Measurement of radical scavenging activity of various C30 carotenoid structures revealed that acyclic C30 carotenoids showed higher radical scavenging activity than did DL-α-tocopherol. We could assume high potential biological activity of the novel structures of C30 carotenoids as well, based on the neuronal differentiation activity observed for the monocyclic C30 carotenoid 4,4′-diapotorulene on rat bone marrow mesenchymal stem cells. Our results demonstrate that a series of structurally novel carotenoids possessing biologically beneficial properties can be synthesized in E. coli. PMID:26902326

  17. [Structure and biological activity of glycosphingolipids from starfish and feather stars].

    PubMed

    Inagaki, Masanori

    2008-08-01

    Glycosphingolipids (GSLs) are contained in a various cell membranes and have recently been implicated in many physiologic functions. They are classified based on their sugar moieties into ceramides, cerebrosides, sulfatides, ceramide-oligohexosides, globosides, and gangliosides. A number of GSLs have been obtained from marine invertebrates such as echinoderms, poriferans, and mollusks and have unique biological activities. During the course of our search for biologically active GSLs from echinoderms, we conducted the isolation and structural elucidation of GSLs from starfish and feather stars and found numerous GSLs, some of which have unique structures. In particular, gangliosides from feather stars were unique in that the sialic acids bind to inositol-phosphoceramide. We also found that the GSLs from starfish and feather stars possess neuritogenic activity toward the rat pheochromocytoma cell line PC12, antihyperglycemic effects against type 2 diabetic BKS. Cg-m+/+Leprdb/J (db/db) mice, and antiosteoporosis effects toward the osteoporosis model mice (OVX mice). These biological activities are thought to be related to dementia, osteoporosis, and diabetes, which are becoming social problems, and are expected to become the seeds of preventive or therapeutic drugs for these illness. PMID:18670184

  18. Automated Structure-Activity Relationship Mining: Connecting Chemical Structure to Biological Profiles.

    PubMed

    Wawer, Mathias J; Jaramillo, David E; Dančík, Vlado; Fass, Daniel M; Haggarty, Stephen J; Shamji, Alykhan F; Wagner, Bridget K; Schreiber, Stuart L; Clemons, Paul A

    2014-06-01

    Understanding the structure-activity relationships (SARs) of small molecules is important for developing probes and novel therapeutic agents in chemical biology and drug discovery. Increasingly, multiplexed small-molecule profiling assays allow simultaneous measurement of many biological response parameters for the same compound (e.g., expression levels for many genes or binding constants against many proteins). Although such methods promise to capture SARs with high granularity, few computational methods are available to support SAR analyses of high-dimensional compound activity profiles. Many of these methods are not generally applicable or reduce the activity space to scalar summary statistics before establishing SARs. In this article, we present a versatile computational method that automatically extracts interpretable SAR rules from high-dimensional profiling data. The rules connect chemical structural features of compounds to patterns in their biological activity profiles. We applied our method to data from novel cell-based gene-expression and imaging assays collected on more than 30,000 small molecules. Based on the rules identified for this data set, we prioritized groups of compounds for further study, including a novel set of putative histone deacetylase inhibitors. PMID:24710340

  19. Generation of structurally novel short carotenoids and study of their biological activity.

    PubMed

    Kim, Se H; Kim, Moon S; Lee, Bun Y; Lee, Pyung C

    2016-01-01

    Recent research interest in phytochemicals has consistently driven the efforts in the metabolic engineering field toward microbial production of various carotenoids. In spite of systematic studies, the possibility of using C30 carotenoids as biologically functional compounds has not been explored thus far. Here, we generated 13 novel structures of C30 carotenoids and one C35 carotenoid, including acyclic, monocyclic, and bicyclic structures, through directed evolution and combinatorial biosynthesis, in Escherichia coli. Measurement of radical scavenging activity of various C30 carotenoid structures revealed that acyclic C30 carotenoids showed higher radical scavenging activity than did DL-α-tocopherol. We could assume high potential biological activity of the novel structures of C30 carotenoids as well, based on the neuronal differentiation activity observed for the monocyclic C30 carotenoid 4,4'-diapotorulene on rat bone marrow mesenchymal stem cells. Our results demonstrate that a series of structurally novel carotenoids possessing biologically beneficial properties can be synthesized in E. coli. PMID:26902326

  20. p-Coumaric acid and its conjugates: dietary sources, pharmacokinetic properties and biological activities.

    PubMed

    Pei, Kehan; Ou, Juanying; Huang, Junqing; Ou, Shiyi

    2016-07-01

    p-Coumaric acid (4-hydroxycinnamic acid) is a phenolic acid that has low toxicity in mice (LD50 = 2850 mg kg(-1) body weight), serves as a precursor of other phenolic compounds, and exists either in free or conjugated form in plants. Conjugates of p-coumaric acid have been extensively studied in recent years due to their bioactivities. In this review, the occurrence, bioavailability and bioaccessibility of p-coumaric acid and its conjugates with mono-, oligo- and polysaccharides, alkyl alcohols, organic acids, amine and lignin are discussed. Their biological activities, including antioxidant, anti-cancer, antimicrobial, antivirus, anti-inflammatory, antiplatelet aggregation, anxiolytic, antipyretic, analgesic, and anti-arthritis activities, and their mitigatory effects against diabetes, obesity, hyperlipaemia and gout are compared. Cumulative evidence from multiple studies indicates that conjugation of p-coumaric acid greatly strengthens its biological activities; however, the high biological activity but low absorption of its conjugates remains a puzzle. © 2015 Society of Chemical Industry. PMID:26692250